xref: /vim-8.2.3635/src/vim9compile.c (revision ca0627df)
1 /* vi:set ts=8 sts=4 sw=4 noet:
2  *
3  * VIM - Vi IMproved	by Bram Moolenaar
4  *
5  * Do ":help uganda"  in Vim to read copying and usage conditions.
6  * Do ":help credits" in Vim to see a list of people who contributed.
7  * See README.txt for an overview of the Vim source code.
8  */
9 
10 /*
11  * vim9compile.c: :def and dealing with instructions
12  */
13 
14 #define USING_FLOAT_STUFF
15 #include "vim.h"
16 
17 #if defined(FEAT_EVAL) || defined(PROTO)
18 
19 #ifdef VMS
20 # include <float.h>
21 #endif
22 
23 #define DEFINE_VIM9_GLOBALS
24 #include "vim9.h"
25 
26 // values for ctx_skip
27 typedef enum {
28     SKIP_NOT,		// condition is a constant, produce code
29     SKIP_YES,		// condition is a constant, do NOT produce code
30     SKIP_UNKNOWN	// condition is not a constant, produce code
31 } skip_T;
32 
33 /*
34  * Chain of jump instructions where the end label needs to be set.
35  */
36 typedef struct endlabel_S endlabel_T;
37 struct endlabel_S {
38     endlabel_T	*el_next;	    // chain end_label locations
39     int		el_end_label;	    // instruction idx where to set end
40 };
41 
42 /*
43  * info specific for the scope of :if / elseif / else
44  */
45 typedef struct {
46     int		is_seen_else;
47     int		is_seen_skip_not;   // a block was unconditionally executed
48     int		is_had_return;	    // every block ends in :return
49     int		is_if_label;	    // instruction idx at IF or ELSEIF
50     endlabel_T	*is_end_label;	    // instructions to set end label
51 } ifscope_T;
52 
53 /*
54  * info specific for the scope of :while
55  */
56 typedef struct {
57     int		ws_top_label;	    // instruction idx at WHILE
58     endlabel_T	*ws_end_label;	    // instructions to set end
59 } whilescope_T;
60 
61 /*
62  * info specific for the scope of :for
63  */
64 typedef struct {
65     int		fs_top_label;	    // instruction idx at FOR
66     endlabel_T	*fs_end_label;	    // break instructions
67 } forscope_T;
68 
69 /*
70  * info specific for the scope of :try
71  */
72 typedef struct {
73     int		ts_try_label;	    // instruction idx at TRY
74     endlabel_T	*ts_end_label;	    // jump to :finally or :endtry
75     int		ts_catch_label;	    // instruction idx of last CATCH
76     int		ts_caught_all;	    // "catch" without argument encountered
77 } tryscope_T;
78 
79 typedef enum {
80     NO_SCOPE,
81     IF_SCOPE,
82     WHILE_SCOPE,
83     FOR_SCOPE,
84     TRY_SCOPE,
85     BLOCK_SCOPE
86 } scopetype_T;
87 
88 /*
89  * Info for one scope, pointed to by "ctx_scope".
90  */
91 typedef struct scope_S scope_T;
92 struct scope_S {
93     scope_T	*se_outer;	    // scope containing this one
94     scopetype_T se_type;
95     int		se_local_count;	    // ctx_locals.ga_len before scope
96     skip_T	se_skip_save;	    // ctx_skip before the block
97     union {
98 	ifscope_T	se_if;
99 	whilescope_T	se_while;
100 	forscope_T	se_for;
101 	tryscope_T	se_try;
102     } se_u;
103 };
104 
105 /*
106  * Entry for "ctx_locals".  Used for arguments and local variables.
107  */
108 typedef struct {
109     char_u	*lv_name;
110     type_T	*lv_type;
111     int		lv_idx;		// index of the variable on the stack
112     int		lv_from_outer;	// nesting level, using ctx_outer scope
113     int		lv_const;	// when TRUE cannot be assigned to
114     int		lv_arg;		// when TRUE this is an argument
115 } lvar_T;
116 
117 // Destination for an assignment or ":unlet" with an index.
118 typedef enum {
119     dest_local,
120     dest_option,
121     dest_env,
122     dest_global,
123     dest_buffer,
124     dest_window,
125     dest_tab,
126     dest_vimvar,
127     dest_script,
128     dest_reg,
129     dest_expr,
130 } assign_dest_T;
131 
132 // Used by compile_lhs() to store information about the LHS of an assignment
133 // and one argument of ":unlet" with an index.
134 typedef struct {
135     assign_dest_T   lhs_dest;	    // type of destination
136 
137     char_u	    *lhs_name;	    // allocated name excluding the last
138 				    // "[expr]" or ".name".
139     size_t	    lhs_varlen;	    // length of the variable without
140 				    // "[expr]" or ".name"
141     char_u	    *lhs_whole;	    // allocated name including the last
142 				    // "[expr]" or ".name" for :redir
143     size_t	    lhs_varlen_total; // length of the variable including
144 				      // any "[expr]" or ".name"
145     char_u	    *lhs_dest_end;  // end of the destination, including
146 				    // "[expr]" or ".name".
147 
148     int		    lhs_has_index;  // has "[expr]" or ".name"
149 
150     int		    lhs_new_local;  // create new local variable
151     int		    lhs_opt_flags;  // for when destination is an option
152     int		    lhs_vimvaridx;  // for when destination is a v:var
153 
154     lvar_T	    lhs_local_lvar; // used for existing local destination
155     lvar_T	    lhs_arg_lvar;   // used for argument destination
156     lvar_T	    *lhs_lvar;	    // points to destination lvar
157     int		    lhs_scriptvar_sid;
158     int		    lhs_scriptvar_idx;
159 
160     int		    lhs_has_type;   // type was specified
161     type_T	    *lhs_type;
162     type_T	    *lhs_member_type;
163 
164     int		    lhs_append;	    // used by ISN_REDIREND
165 } lhs_T;
166 
167 /*
168  * Context for compiling lines of Vim script.
169  * Stores info about the local variables and condition stack.
170  */
171 struct cctx_S {
172     ufunc_T	*ctx_ufunc;	    // current function
173     int		ctx_lnum;	    // line number in current function
174     char_u	*ctx_line_start;    // start of current line or NULL
175     garray_T	ctx_instr;	    // generated instructions
176 
177     int		ctx_prev_lnum;	    // line number below previous command, for
178 				    // debugging
179 
180     compiletype_T ctx_compile_type;
181 
182     garray_T	ctx_locals;	    // currently visible local variables
183 
184     int		ctx_has_closure;    // set to one if a closures was created in
185 				    // the function
186 
187     garray_T	ctx_imports;	    // imported items
188 
189     skip_T	ctx_skip;
190     scope_T	*ctx_scope;	    // current scope, NULL at toplevel
191     int		ctx_had_return;	    // last seen statement was "return"
192 
193     cctx_T	*ctx_outer;	    // outer scope for lambda or nested
194 				    // function
195     int		ctx_outer_used;	    // var in ctx_outer was used
196 
197     garray_T	ctx_type_stack;	    // type of each item on the stack
198     garray_T	*ctx_type_list;	    // list of pointers to allocated types
199 
200     int		ctx_has_cmdmod;	    // ISN_CMDMOD was generated
201 
202     lhs_T	ctx_redir_lhs;	    // LHS for ":redir => var", valid when
203 				    // lhs_name is not NULL
204 };
205 
206 static void delete_def_function_contents(dfunc_T *dfunc, int mark_deleted);
207 
208 /*
209  * Lookup variable "name" in the local scope and return it in "lvar".
210  * "lvar->lv_from_outer" is incremented accordingly.
211  * If "lvar" is NULL only check if the variable can be found.
212  * Return FAIL if not found.
213  */
214     static int
215 lookup_local(char_u *name, size_t len, lvar_T *lvar, cctx_T *cctx)
216 {
217     int	    idx;
218     lvar_T  *lvp;
219 
220     if (len == 0)
221 	return FAIL;
222 
223     // Find local in current function scope.
224     for (idx = 0; idx < cctx->ctx_locals.ga_len; ++idx)
225     {
226 	lvp = ((lvar_T *)cctx->ctx_locals.ga_data) + idx;
227 	if (STRNCMP(name, lvp->lv_name, len) == 0
228 					       && STRLEN(lvp->lv_name) == len)
229 	{
230 	    if (lvar != NULL)
231 	    {
232 		*lvar = *lvp;
233 		lvar->lv_from_outer = 0;
234 	    }
235 	    return OK;
236 	}
237     }
238 
239     // Find local in outer function scope.
240     if (cctx->ctx_outer != NULL)
241     {
242 	if (lookup_local(name, len, lvar, cctx->ctx_outer) == OK)
243 	{
244 	    if (lvar != NULL)
245 	    {
246 		cctx->ctx_outer_used = TRUE;
247 		++lvar->lv_from_outer;
248 	    }
249 	    return OK;
250 	}
251     }
252 
253     return FAIL;
254 }
255 
256 /*
257  * Lookup an argument in the current function and an enclosing function.
258  * Returns the argument index in "idxp"
259  * Returns the argument type in "type"
260  * Sets "gen_load_outer" to TRUE if found in outer scope.
261  * Returns OK when found, FAIL otherwise.
262  */
263     static int
264 arg_exists(
265 	char_u	*name,
266 	size_t	len,
267 	int	*idxp,
268 	type_T	**type,
269 	int	*gen_load_outer,
270 	cctx_T	*cctx)
271 {
272     int	    idx;
273     char_u  *va_name;
274 
275     if (len == 0)
276 	return FAIL;
277     for (idx = 0; idx < cctx->ctx_ufunc->uf_args_visible; ++idx)
278     {
279 	char_u *arg = FUNCARG(cctx->ctx_ufunc, idx);
280 
281 	if (STRNCMP(name, arg, len) == 0 && arg[len] == NUL)
282 	{
283 	    if (idxp != NULL)
284 	    {
285 		// Arguments are located above the frame pointer.  One further
286 		// if there is a vararg argument
287 		*idxp = idx - (cctx->ctx_ufunc->uf_args.ga_len
288 							    + STACK_FRAME_SIZE)
289 			      + (cctx->ctx_ufunc->uf_va_name != NULL ? -1 : 0);
290 
291 		if (cctx->ctx_ufunc->uf_arg_types != NULL)
292 		    *type = cctx->ctx_ufunc->uf_arg_types[idx];
293 		else
294 		    *type = &t_any;
295 	    }
296 	    return OK;
297 	}
298     }
299 
300     va_name = cctx->ctx_ufunc->uf_va_name;
301     if (va_name != NULL
302 		    && STRNCMP(name, va_name, len) == 0 && va_name[len] == NUL)
303     {
304 	if (idxp != NULL)
305 	{
306 	    // varargs is always the last argument
307 	    *idxp = -STACK_FRAME_SIZE - 1;
308 	    *type = cctx->ctx_ufunc->uf_va_type;
309 	}
310 	return OK;
311     }
312 
313     if (cctx->ctx_outer != NULL)
314     {
315 	// Lookup the name for an argument of the outer function.
316 	if (arg_exists(name, len, idxp, type, gen_load_outer, cctx->ctx_outer)
317 									 == OK)
318 	{
319 	    if (gen_load_outer != NULL)
320 		++*gen_load_outer;
321 	    return OK;
322 	}
323     }
324 
325     return FAIL;
326 }
327 
328 /*
329  * Lookup a script-local variable in the current script, possibly defined in a
330  * block that contains the function "cctx->ctx_ufunc".
331  * "cctx" is NULL at the script level.
332  * If "len" is <= 0 "name" must be NUL terminated.
333  * Return NULL when not found.
334  */
335     static sallvar_T *
336 find_script_var(char_u *name, size_t len, cctx_T *cctx)
337 {
338     scriptitem_T    *si = SCRIPT_ITEM(current_sctx.sc_sid);
339     hashitem_T	    *hi;
340     int		    cc;
341     sallvar_T	    *sav;
342     sallvar_T	    *found_sav;
343     ufunc_T	    *ufunc;
344 
345     // Find the list of all script variables with the right name.
346     if (len > 0)
347     {
348 	cc = name[len];
349 	name[len] = NUL;
350     }
351     hi = hash_find(&si->sn_all_vars.dv_hashtab, name);
352     if (len > 0)
353 	name[len] = cc;
354     if (HASHITEM_EMPTY(hi))
355 	return NULL;
356 
357     sav = HI2SAV(hi);
358     if (sav->sav_block_id == 0)
359 	// variable defined in the top script scope is always visible
360 	return sav;
361 
362     if (cctx == NULL)
363     {
364 	// Not in a function scope, find variable with block id equal to or
365 	// smaller than the current block id.
366 	while (sav != NULL)
367 	{
368 	    if (sav->sav_block_id <= si->sn_current_block_id)
369 		break;
370 	    sav = sav->sav_next;
371 	}
372 	return sav;
373     }
374 
375     // Go over the variables with this name and find one that was visible
376     // from the function.
377     ufunc = cctx->ctx_ufunc;
378     found_sav = sav;
379     while (sav != NULL)
380     {
381 	int idx;
382 
383 	// Go over the blocks that this function was defined in.  If the
384 	// variable block ID matches it was visible to the function.
385 	for (idx = 0; idx < ufunc->uf_block_depth; ++idx)
386 	    if (ufunc->uf_block_ids[idx] == sav->sav_block_id)
387 		return sav;
388 	sav = sav->sav_next;
389     }
390 
391     // Not found, assume variable at script level was visible.
392     return found_sav;
393 }
394 
395 /*
396  * Return TRUE if the script context is Vim9 script.
397  */
398     static int
399 script_is_vim9()
400 {
401     return SCRIPT_ITEM(current_sctx.sc_sid)->sn_version == SCRIPT_VERSION_VIM9;
402 }
403 
404 /*
405  * Lookup a variable (without s: prefix) in the current script.
406  * "cctx" is NULL at the script level.
407  * Returns OK or FAIL.
408  */
409     static int
410 script_var_exists(char_u *name, size_t len, cctx_T *cctx)
411 {
412     if (current_sctx.sc_sid <= 0)
413 	return FAIL;
414     if (script_is_vim9())
415     {
416 	// Check script variables that were visible where the function was
417 	// defined.
418 	if (find_script_var(name, len, cctx) != NULL)
419 	    return OK;
420     }
421     else
422     {
423 	hashtab_T	*ht = &SCRIPT_VARS(current_sctx.sc_sid);
424 	dictitem_T	*di;
425 	int		cc;
426 
427 	// Check script variables that are currently visible
428 	cc = name[len];
429 	name[len] = NUL;
430 	di = find_var_in_ht(ht, 0, name, TRUE);
431 	name[len] = cc;
432 	if (di != NULL)
433 	    return OK;
434     }
435 
436     return FAIL;
437 }
438 
439 /*
440  * Return TRUE if "name" is a local variable, argument, script variable or
441  * imported.
442  */
443     static int
444 variable_exists(char_u *name, size_t len, cctx_T *cctx)
445 {
446     return (cctx != NULL
447 		&& (lookup_local(name, len, NULL, cctx) == OK
448 		    || arg_exists(name, len, NULL, NULL, NULL, cctx) == OK))
449 	    || script_var_exists(name, len, cctx) == OK
450 	    || find_imported(name, len, cctx) != NULL;
451 }
452 
453 /*
454  * Return TRUE if "name" is a local variable, argument, script variable,
455  * imported or function.
456  */
457     static int
458 item_exists(char_u *name, size_t len, int cmd UNUSED, cctx_T *cctx)
459 {
460     int	    is_global;
461     char_u  *p;
462 
463     if (variable_exists(name, len, cctx))
464 	return TRUE;
465 
466     // This is similar to what is in lookup_scriptitem():
467     // Find a function, so that a following "->" works.
468     // Require "(" or "->" to follow, "Cmd" is a user command while "Cmd()" is
469     // a function call.
470     p = skipwhite(name + len);
471 
472     if (name[len] == '(' || (p[0] == '-' && p[1] == '>'))
473     {
474 	// Do not check for an internal function, since it might also be a
475 	// valid command, such as ":split" versus "split()".
476 	// Skip "g:" before a function name.
477 	is_global = (name[0] == 'g' && name[1] == ':');
478 	return find_func(is_global ? name + 2 : name, is_global, cctx) != NULL;
479     }
480     return FALSE;
481 }
482 
483 /*
484  * Check if "p[len]" is already defined, either in script "import_sid" or in
485  * compilation context "cctx".  "cctx" is NULL at the script level.
486  * Does not check the global namespace.
487  * If "is_arg" is TRUE the error message is for an argument name.
488  * Return FAIL and give an error if it defined.
489  */
490     int
491 check_defined(char_u *p, size_t len, cctx_T *cctx, int is_arg)
492 {
493     int		c = p[len];
494     ufunc_T	*ufunc = NULL;
495 
496     // underscore argument is OK
497     if (len == 1 && *p == '_')
498 	return OK;
499 
500     if (script_var_exists(p, len, cctx) == OK)
501     {
502 	if (is_arg)
503 	    semsg(_(e_argument_already_declared_in_script_str), p);
504 	else
505 	    semsg(_(e_variable_already_declared_in_script_str), p);
506 	return FAIL;
507     }
508 
509     p[len] = NUL;
510     if ((cctx != NULL
511 		&& (lookup_local(p, len, NULL, cctx) == OK
512 		    || arg_exists(p, len, NULL, NULL, NULL, cctx) == OK))
513 	    || find_imported(p, len, cctx) != NULL
514 	    || (ufunc = find_func_even_dead(p, FALSE, cctx)) != NULL)
515     {
516 	// A local or script-local function can shadow a global function.
517 	if (ufunc == NULL || ((ufunc->uf_flags & FC_DEAD) == 0
518 		    && (!func_is_global(ufunc)
519 					     || (p[0] == 'g' && p[1] == ':'))))
520 	{
521 	    if (is_arg)
522 		semsg(_(e_argument_name_shadows_existing_variable_str), p);
523 	    else
524 		semsg(_(e_name_already_defined_str), p);
525 	    p[len] = c;
526 	    return FAIL;
527 	}
528     }
529     p[len] = c;
530     return OK;
531 }
532 
533 
534 /////////////////////////////////////////////////////////////////////
535 // Following generate_ functions expect the caller to call ga_grow().
536 
537 #define RETURN_NULL_IF_SKIP(cctx) if (cctx->ctx_skip == SKIP_YES) return NULL
538 #define RETURN_OK_IF_SKIP(cctx) if (cctx->ctx_skip == SKIP_YES) return OK
539 
540 /*
541  * Generate an instruction without arguments.
542  * Returns a pointer to the new instruction, NULL if failed.
543  */
544     static isn_T *
545 generate_instr(cctx_T *cctx, isntype_T isn_type)
546 {
547     garray_T	*instr = &cctx->ctx_instr;
548     isn_T	*isn;
549 
550     RETURN_NULL_IF_SKIP(cctx);
551     if (GA_GROW_FAILS(instr, 1))
552 	return NULL;
553     isn = ((isn_T *)instr->ga_data) + instr->ga_len;
554     isn->isn_type = isn_type;
555     isn->isn_lnum = cctx->ctx_lnum + 1;
556     ++instr->ga_len;
557 
558     return isn;
559 }
560 
561 /*
562  * Generate an instruction without arguments.
563  * "drop" will be removed from the stack.
564  * Returns a pointer to the new instruction, NULL if failed.
565  */
566     static isn_T *
567 generate_instr_drop(cctx_T *cctx, isntype_T isn_type, int drop)
568 {
569     garray_T	*stack = &cctx->ctx_type_stack;
570 
571     RETURN_NULL_IF_SKIP(cctx);
572     stack->ga_len -= drop;
573     return generate_instr(cctx, isn_type);
574 }
575 
576 /*
577  * Generate instruction "isn_type" and put "type" on the type stack.
578  */
579     static isn_T *
580 generate_instr_type(cctx_T *cctx, isntype_T isn_type, type_T *type)
581 {
582     isn_T	*isn;
583     garray_T	*stack = &cctx->ctx_type_stack;
584 
585     if ((isn = generate_instr(cctx, isn_type)) == NULL)
586 	return NULL;
587 
588     if (GA_GROW_FAILS(stack, 1))
589 	return NULL;
590     ((type_T **)stack->ga_data)[stack->ga_len] = type == NULL ? &t_any : type;
591     ++stack->ga_len;
592 
593     return isn;
594 }
595 
596 /*
597  * Generate an ISN_DEBUG instruction.
598  */
599     static isn_T *
600 generate_instr_debug(cctx_T *cctx)
601 {
602     isn_T	*isn;
603     dfunc_T	*dfunc = ((dfunc_T *)def_functions.ga_data)
604 					       + cctx->ctx_ufunc->uf_dfunc_idx;
605 
606     if ((isn = generate_instr(cctx, ISN_DEBUG)) == NULL)
607 	return NULL;
608     isn->isn_arg.debug.dbg_var_names_len = dfunc->df_var_names.ga_len;
609     isn->isn_arg.debug.dbg_break_lnum = cctx->ctx_prev_lnum;
610     return isn;
611 }
612 
613 /*
614  * If type at "offset" isn't already VAR_STRING then generate ISN_2STRING.
615  * But only for simple types.
616  * When "tolerant" is TRUE convert most types to string, e.g. a List.
617  */
618     static int
619 may_generate_2STRING(int offset, int tolerant, cctx_T *cctx)
620 {
621     isn_T	*isn;
622     isntype_T	isntype = ISN_2STRING;
623     garray_T	*stack = &cctx->ctx_type_stack;
624     type_T	**type;
625 
626     RETURN_OK_IF_SKIP(cctx);
627     type = ((type_T **)stack->ga_data) + stack->ga_len + offset;
628     switch ((*type)->tt_type)
629     {
630 	// nothing to be done
631 	case VAR_STRING: return OK;
632 
633 	// conversion possible
634 	case VAR_SPECIAL:
635 	case VAR_BOOL:
636 	case VAR_NUMBER:
637 	case VAR_FLOAT:
638 			 break;
639 
640 	// conversion possible (with runtime check)
641 	case VAR_ANY:
642 	case VAR_UNKNOWN:
643 			 isntype = ISN_2STRING_ANY;
644 			 break;
645 
646 	// conversion possible when tolerant
647 	case VAR_LIST:
648 			 if (tolerant)
649 			 {
650 			     isntype = ISN_2STRING_ANY;
651 			     break;
652 			 }
653 			 // FALLTHROUGH
654 
655 	// conversion not possible
656 	case VAR_VOID:
657 	case VAR_BLOB:
658 	case VAR_FUNC:
659 	case VAR_PARTIAL:
660 	case VAR_DICT:
661 	case VAR_JOB:
662 	case VAR_CHANNEL:
663 	case VAR_INSTR:
664 			 to_string_error((*type)->tt_type);
665 			 return FAIL;
666     }
667 
668     *type = &t_string;
669     if ((isn = generate_instr(cctx, isntype)) == NULL)
670 	return FAIL;
671     isn->isn_arg.tostring.offset = offset;
672     isn->isn_arg.tostring.tolerant = tolerant;
673 
674     return OK;
675 }
676 
677     static int
678 check_number_or_float(vartype_T type1, vartype_T type2, char_u *op)
679 {
680     if (!((type1 == VAR_NUMBER || type1 == VAR_FLOAT || type1 == VAR_ANY)
681 	    && (type2 == VAR_NUMBER || type2 == VAR_FLOAT
682 							 || type2 == VAR_ANY)))
683     {
684 	if (*op == '+')
685 	    emsg(_(e_wrong_argument_type_for_plus));
686 	else
687 	    semsg(_(e_char_requires_number_or_float_arguments), *op);
688 	return FAIL;
689     }
690     return OK;
691 }
692 
693 /*
694  * Generate instruction for "+".  For a list this creates a new list.
695  */
696     static int
697 generate_add_instr(
698 	cctx_T *cctx,
699 	vartype_T vartype,
700 	type_T *type1,
701 	type_T *type2,
702 	exprtype_T expr_type)
703 {
704     garray_T	*stack = &cctx->ctx_type_stack;
705     isn_T	*isn = generate_instr_drop(cctx,
706 		      vartype == VAR_NUMBER ? ISN_OPNR
707 		    : vartype == VAR_LIST ? ISN_ADDLIST
708 		    : vartype == VAR_BLOB ? ISN_ADDBLOB
709 #ifdef FEAT_FLOAT
710 		    : vartype == VAR_FLOAT ? ISN_OPFLOAT
711 #endif
712 		    : ISN_OPANY, 1);
713 
714     if (vartype != VAR_LIST && vartype != VAR_BLOB
715 	    && type1->tt_type != VAR_ANY
716 	    && type2->tt_type != VAR_ANY
717 	    && check_number_or_float(
718 			type1->tt_type, type2->tt_type, (char_u *)"+") == FAIL)
719 	return FAIL;
720 
721     if (isn != NULL)
722     {
723 	if (isn->isn_type == ISN_ADDLIST)
724 	    isn->isn_arg.op.op_type = expr_type;
725 	else
726 	    isn->isn_arg.op.op_type = EXPR_ADD;
727     }
728 
729     // When concatenating two lists with different member types the member type
730     // becomes "any".
731     if (vartype == VAR_LIST
732 	    && type1->tt_type == VAR_LIST && type2->tt_type == VAR_LIST
733 	    && type1->tt_member != type2->tt_member)
734 	(((type_T **)stack->ga_data)[stack->ga_len - 1]) = &t_list_any;
735 
736     return isn == NULL ? FAIL : OK;
737 }
738 
739 /*
740  * Get the type to use for an instruction for an operation on "type1" and
741  * "type2".  If they are matching use a type-specific instruction. Otherwise
742  * fall back to runtime type checking.
743  */
744     static vartype_T
745 operator_type(type_T *type1, type_T *type2)
746 {
747     if (type1->tt_type == type2->tt_type
748 	    && (type1->tt_type == VAR_NUMBER
749 		|| type1->tt_type == VAR_LIST
750 #ifdef FEAT_FLOAT
751 		|| type1->tt_type == VAR_FLOAT
752 #endif
753 		|| type1->tt_type == VAR_BLOB))
754 	return type1->tt_type;
755     return VAR_ANY;
756 }
757 
758 /*
759  * Generate an instruction with two arguments.  The instruction depends on the
760  * type of the arguments.
761  */
762     static int
763 generate_two_op(cctx_T *cctx, char_u *op)
764 {
765     garray_T	*stack = &cctx->ctx_type_stack;
766     type_T	*type1;
767     type_T	*type2;
768     vartype_T	vartype;
769     isn_T	*isn;
770 
771     RETURN_OK_IF_SKIP(cctx);
772 
773     // Get the known type of the two items on the stack.
774     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2];
775     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1];
776     vartype = operator_type(type1, type2);
777 
778     switch (*op)
779     {
780 	case '+':
781 		  if (generate_add_instr(cctx, vartype, type1, type2,
782 							    EXPR_COPY) == FAIL)
783 		      return FAIL;
784 		  break;
785 
786 	case '-':
787 	case '*':
788 	case '/': if (check_number_or_float(type1->tt_type, type2->tt_type,
789 								   op) == FAIL)
790 		      return FAIL;
791 		  if (vartype == VAR_NUMBER)
792 		      isn = generate_instr_drop(cctx, ISN_OPNR, 1);
793 #ifdef FEAT_FLOAT
794 		  else if (vartype == VAR_FLOAT)
795 		      isn = generate_instr_drop(cctx, ISN_OPFLOAT, 1);
796 #endif
797 		  else
798 		      isn = generate_instr_drop(cctx, ISN_OPANY, 1);
799 		  if (isn != NULL)
800 		      isn->isn_arg.op.op_type = *op == '*'
801 				 ? EXPR_MULT : *op == '/'? EXPR_DIV : EXPR_SUB;
802 		  break;
803 
804 	case '%': if ((type1->tt_type != VAR_ANY
805 					       && type1->tt_type != VAR_NUMBER)
806 			  || (type2->tt_type != VAR_ANY
807 					      && type2->tt_type != VAR_NUMBER))
808 		  {
809 		      emsg(_(e_percent_requires_number_arguments));
810 		      return FAIL;
811 		  }
812 		  isn = generate_instr_drop(cctx,
813 			      vartype == VAR_NUMBER ? ISN_OPNR : ISN_OPANY, 1);
814 		  if (isn != NULL)
815 		      isn->isn_arg.op.op_type = EXPR_REM;
816 		  break;
817     }
818 
819     // correct type of result
820     if (vartype == VAR_ANY)
821     {
822 	type_T *type = &t_any;
823 
824 #ifdef FEAT_FLOAT
825 	// float+number and number+float results in float
826 	if ((type1->tt_type == VAR_NUMBER || type1->tt_type == VAR_FLOAT)
827 		&& (type2->tt_type == VAR_NUMBER || type2->tt_type == VAR_FLOAT))
828 	    type = &t_float;
829 #endif
830 	((type_T **)stack->ga_data)[stack->ga_len - 1] = type;
831     }
832 
833     return OK;
834 }
835 
836 /*
837  * Get the instruction to use for comparing "type1" with "type2"
838  * Return ISN_DROP when failed.
839  */
840     static isntype_T
841 get_compare_isn(exprtype_T exprtype, vartype_T type1, vartype_T type2)
842 {
843     isntype_T	isntype = ISN_DROP;
844 
845     if (type1 == VAR_UNKNOWN)
846 	type1 = VAR_ANY;
847     if (type2 == VAR_UNKNOWN)
848 	type2 = VAR_ANY;
849 
850     if (type1 == type2)
851     {
852 	switch (type1)
853 	{
854 	    case VAR_BOOL: isntype = ISN_COMPAREBOOL; break;
855 	    case VAR_SPECIAL: isntype = ISN_COMPARESPECIAL; break;
856 	    case VAR_NUMBER: isntype = ISN_COMPARENR; break;
857 	    case VAR_FLOAT: isntype = ISN_COMPAREFLOAT; break;
858 	    case VAR_STRING: isntype = ISN_COMPARESTRING; break;
859 	    case VAR_BLOB: isntype = ISN_COMPAREBLOB; break;
860 	    case VAR_LIST: isntype = ISN_COMPARELIST; break;
861 	    case VAR_DICT: isntype = ISN_COMPAREDICT; break;
862 	    case VAR_FUNC: isntype = ISN_COMPAREFUNC; break;
863 	    default: isntype = ISN_COMPAREANY; break;
864 	}
865     }
866     else if (type1 == VAR_ANY || type2 == VAR_ANY
867 	    || ((type1 == VAR_NUMBER || type1 == VAR_FLOAT)
868 	      && (type2 == VAR_NUMBER || type2 == VAR_FLOAT)))
869 	isntype = ISN_COMPAREANY;
870 
871     if ((exprtype == EXPR_IS || exprtype == EXPR_ISNOT)
872 	    && (isntype == ISN_COMPAREBOOL
873 	    || isntype == ISN_COMPARESPECIAL
874 	    || isntype == ISN_COMPARENR
875 	    || isntype == ISN_COMPAREFLOAT))
876     {
877 	semsg(_(e_cannot_use_str_with_str),
878 		exprtype == EXPR_IS ? "is" : "isnot" , vartype_name(type1));
879 	return ISN_DROP;
880     }
881     if (isntype == ISN_DROP
882 	    || ((exprtype != EXPR_EQUAL && exprtype != EXPR_NEQUAL
883 		    && (type1 == VAR_BOOL || type1 == VAR_SPECIAL
884 		       || type2 == VAR_BOOL || type2 == VAR_SPECIAL)))
885 	    || ((exprtype != EXPR_EQUAL && exprtype != EXPR_NEQUAL
886 				 && exprtype != EXPR_IS && exprtype != EXPR_ISNOT
887 		    && (type1 == VAR_BLOB || type2 == VAR_BLOB
888 			|| type1 == VAR_LIST || type2 == VAR_LIST))))
889     {
890 	semsg(_(e_cannot_compare_str_with_str),
891 		vartype_name(type1), vartype_name(type2));
892 	return ISN_DROP;
893     }
894     return isntype;
895 }
896 
897     int
898 check_compare_types(exprtype_T type, typval_T *tv1, typval_T *tv2)
899 {
900     if (get_compare_isn(type, tv1->v_type, tv2->v_type) == ISN_DROP)
901 	return FAIL;
902     return OK;
903 }
904 
905 /*
906  * Generate an ISN_COMPARE* instruction with a boolean result.
907  */
908     static int
909 generate_COMPARE(cctx_T *cctx, exprtype_T exprtype, int ic)
910 {
911     isntype_T	isntype;
912     isn_T	*isn;
913     garray_T	*stack = &cctx->ctx_type_stack;
914     vartype_T	type1;
915     vartype_T	type2;
916 
917     RETURN_OK_IF_SKIP(cctx);
918 
919     // Get the known type of the two items on the stack.  If they are matching
920     // use a type-specific instruction. Otherwise fall back to runtime type
921     // checking.
922     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2]->tt_type;
923     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1]->tt_type;
924     isntype = get_compare_isn(exprtype, type1, type2);
925     if (isntype == ISN_DROP)
926 	return FAIL;
927 
928     if ((isn = generate_instr(cctx, isntype)) == NULL)
929 	return FAIL;
930     isn->isn_arg.op.op_type = exprtype;
931     isn->isn_arg.op.op_ic = ic;
932 
933     // takes two arguments, puts one bool back
934     if (stack->ga_len >= 2)
935     {
936 	--stack->ga_len;
937 	((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_bool;
938     }
939 
940     return OK;
941 }
942 
943 /*
944  * Generate an ISN_2BOOL instruction.
945  * "offset" is the offset in the type stack.
946  */
947     static int
948 generate_2BOOL(cctx_T *cctx, int invert, int offset)
949 {
950     isn_T	*isn;
951     garray_T	*stack = &cctx->ctx_type_stack;
952 
953     RETURN_OK_IF_SKIP(cctx);
954     if ((isn = generate_instr(cctx, ISN_2BOOL)) == NULL)
955 	return FAIL;
956     isn->isn_arg.tobool.invert = invert;
957     isn->isn_arg.tobool.offset = offset;
958 
959     // type becomes bool
960     ((type_T **)stack->ga_data)[stack->ga_len + offset] = &t_bool;
961 
962     return OK;
963 }
964 
965 /*
966  * Generate an ISN_COND2BOOL instruction.
967  */
968     static int
969 generate_COND2BOOL(cctx_T *cctx)
970 {
971     isn_T	*isn;
972     garray_T	*stack = &cctx->ctx_type_stack;
973 
974     RETURN_OK_IF_SKIP(cctx);
975     if ((isn = generate_instr(cctx, ISN_COND2BOOL)) == NULL)
976 	return FAIL;
977 
978     // type becomes bool
979     ((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_bool;
980 
981     return OK;
982 }
983 
984     static int
985 generate_TYPECHECK(
986 	cctx_T	    *cctx,
987 	type_T	    *expected,
988 	int	    offset,
989 	int	    argidx)
990 {
991     isn_T	*isn;
992     garray_T	*stack = &cctx->ctx_type_stack;
993 
994     RETURN_OK_IF_SKIP(cctx);
995     if ((isn = generate_instr(cctx, ISN_CHECKTYPE)) == NULL)
996 	return FAIL;
997     isn->isn_arg.type.ct_type = alloc_type(expected);
998     isn->isn_arg.type.ct_off = (int8_T)offset;
999     isn->isn_arg.type.ct_arg_idx = (int8_T)argidx;
1000 
1001     // type becomes expected
1002     ((type_T **)stack->ga_data)[stack->ga_len + offset] = expected;
1003 
1004     return OK;
1005 }
1006 
1007     static int
1008 generate_SETTYPE(
1009 	cctx_T	    *cctx,
1010 	type_T	    *expected)
1011 {
1012     isn_T	*isn;
1013 
1014     RETURN_OK_IF_SKIP(cctx);
1015     if ((isn = generate_instr(cctx, ISN_SETTYPE)) == NULL)
1016 	return FAIL;
1017     isn->isn_arg.type.ct_type = alloc_type(expected);
1018     return OK;
1019 }
1020 
1021 /*
1022  * Return TRUE if "actual" could be "expected" and a runtime typecheck is to be
1023  * used.  Return FALSE if the types will never match.
1024  */
1025     static int
1026 use_typecheck(type_T *actual, type_T *expected)
1027 {
1028     if (actual->tt_type == VAR_ANY
1029 	    || actual->tt_type == VAR_UNKNOWN
1030 	    || (actual->tt_type == VAR_FUNC
1031 		&& (expected->tt_type == VAR_FUNC
1032 					   || expected->tt_type == VAR_PARTIAL)
1033 		&& (actual->tt_member == &t_any || actual->tt_argcount < 0)
1034 		&& ((actual->tt_member == &t_void)
1035 					 == (expected->tt_member == &t_void))))
1036 	return TRUE;
1037     if ((actual->tt_type == VAR_LIST || actual->tt_type == VAR_DICT)
1038 				       && actual->tt_type == expected->tt_type)
1039 	// This takes care of a nested list or dict.
1040 	return use_typecheck(actual->tt_member, expected->tt_member);
1041     return FALSE;
1042 }
1043 
1044 /*
1045  * Check that
1046  * - "actual" matches "expected" type or
1047  * - "actual" is a type that can be "expected" type: add a runtime check; or
1048  * - return FAIL.
1049  * If "actual_is_const" is TRUE then the type won't change at runtime, do not
1050  * generate a TYPECHECK.
1051  */
1052     static int
1053 need_type_where(
1054 	type_T	*actual,
1055 	type_T	*expected,
1056 	int	offset,
1057 	where_T	where,
1058 	cctx_T	*cctx,
1059 	int	silent,
1060 	int	actual_is_const)
1061 {
1062     if (expected == &t_bool && actual != &t_bool
1063 					&& (actual->tt_flags & TTFLAG_BOOL_OK))
1064     {
1065 	// Using "0", "1" or the result of an expression with "&&" or "||" as a
1066 	// boolean is OK but requires a conversion.
1067 	generate_2BOOL(cctx, FALSE, offset);
1068 	return OK;
1069     }
1070 
1071     if (check_type(expected, actual, FALSE, where) == OK)
1072 	return OK;
1073 
1074     // If the actual type can be the expected type add a runtime check.
1075     // If it's a constant a runtime check makes no sense.
1076     if ((!actual_is_const || actual == &t_any)
1077 					    && use_typecheck(actual, expected))
1078     {
1079 	generate_TYPECHECK(cctx, expected, offset, where.wt_index);
1080 	return OK;
1081     }
1082 
1083     if (!silent)
1084 	type_mismatch_where(expected, actual, where);
1085     return FAIL;
1086 }
1087 
1088     int
1089 need_type(
1090 	type_T	*actual,
1091 	type_T	*expected,
1092 	int	offset,
1093 	int	arg_idx,
1094 	cctx_T	*cctx,
1095 	int	silent,
1096 	int	actual_is_const)
1097 {
1098     where_T where = WHERE_INIT;
1099 
1100     where.wt_index = arg_idx;
1101     return need_type_where(actual, expected, offset, where,
1102 						cctx, silent, actual_is_const);
1103 }
1104 
1105 /*
1106  * Check that the top of the type stack has a type that can be used as a
1107  * condition.  Give an error and return FAIL if not.
1108  */
1109     static int
1110 bool_on_stack(cctx_T *cctx)
1111 {
1112     garray_T	*stack = &cctx->ctx_type_stack;
1113     type_T	*type;
1114 
1115     type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1116     if (type == &t_bool)
1117 	return OK;
1118 
1119     if (type == &t_any || type == &t_number || type == &t_number_bool)
1120 	// Number 0 and 1 are OK to use as a bool.  "any" could also be a bool.
1121 	// This requires a runtime type check.
1122 	return generate_COND2BOOL(cctx);
1123 
1124     return need_type(type, &t_bool, -1, 0, cctx, FALSE, FALSE);
1125 }
1126 
1127 /*
1128  * Generate an ISN_PUSHNR instruction.
1129  */
1130     static int
1131 generate_PUSHNR(cctx_T *cctx, varnumber_T number)
1132 {
1133     isn_T	*isn;
1134     garray_T	*stack = &cctx->ctx_type_stack;
1135 
1136     RETURN_OK_IF_SKIP(cctx);
1137     if ((isn = generate_instr_type(cctx, ISN_PUSHNR, &t_number)) == NULL)
1138 	return FAIL;
1139     isn->isn_arg.number = number;
1140 
1141     if (number == 0 || number == 1)
1142 	// A 0 or 1 number can also be used as a bool.
1143 	((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_number_bool;
1144     return OK;
1145 }
1146 
1147 /*
1148  * Generate an ISN_PUSHBOOL instruction.
1149  */
1150     static int
1151 generate_PUSHBOOL(cctx_T *cctx, varnumber_T number)
1152 {
1153     isn_T	*isn;
1154 
1155     RETURN_OK_IF_SKIP(cctx);
1156     if ((isn = generate_instr_type(cctx, ISN_PUSHBOOL, &t_bool)) == NULL)
1157 	return FAIL;
1158     isn->isn_arg.number = number;
1159 
1160     return OK;
1161 }
1162 
1163 /*
1164  * Generate an ISN_PUSHSPEC instruction.
1165  */
1166     static int
1167 generate_PUSHSPEC(cctx_T *cctx, varnumber_T number)
1168 {
1169     isn_T	*isn;
1170 
1171     RETURN_OK_IF_SKIP(cctx);
1172     if ((isn = generate_instr_type(cctx, ISN_PUSHSPEC, &t_special)) == NULL)
1173 	return FAIL;
1174     isn->isn_arg.number = number;
1175 
1176     return OK;
1177 }
1178 
1179 #ifdef FEAT_FLOAT
1180 /*
1181  * Generate an ISN_PUSHF instruction.
1182  */
1183     static int
1184 generate_PUSHF(cctx_T *cctx, float_T fnumber)
1185 {
1186     isn_T	*isn;
1187 
1188     RETURN_OK_IF_SKIP(cctx);
1189     if ((isn = generate_instr_type(cctx, ISN_PUSHF, &t_float)) == NULL)
1190 	return FAIL;
1191     isn->isn_arg.fnumber = fnumber;
1192 
1193     return OK;
1194 }
1195 #endif
1196 
1197 /*
1198  * Generate an ISN_PUSHS instruction.
1199  * Consumes "*str".  When freed *str is set to NULL, unless "str" is NULL.
1200  */
1201     static int
1202 generate_PUSHS(cctx_T *cctx, char_u **str)
1203 {
1204     isn_T	*isn;
1205 
1206     if (cctx->ctx_skip == SKIP_YES)
1207     {
1208 	if (str != NULL)
1209 	    VIM_CLEAR(*str);
1210 	return OK;
1211     }
1212     if ((isn = generate_instr_type(cctx, ISN_PUSHS, &t_string)) == NULL)
1213     {
1214 	if (str != NULL)
1215 	    VIM_CLEAR(*str);
1216 	return FAIL;
1217     }
1218     isn->isn_arg.string = str == NULL ? NULL : *str;
1219 
1220     return OK;
1221 }
1222 
1223 /*
1224  * Generate an ISN_PUSHCHANNEL instruction.
1225  * Consumes "channel".
1226  */
1227     static int
1228 generate_PUSHCHANNEL(cctx_T *cctx, channel_T *channel)
1229 {
1230     isn_T	*isn;
1231 
1232     RETURN_OK_IF_SKIP(cctx);
1233     if ((isn = generate_instr_type(cctx, ISN_PUSHCHANNEL, &t_channel)) == NULL)
1234 	return FAIL;
1235     isn->isn_arg.channel = channel;
1236 
1237     return OK;
1238 }
1239 
1240 /*
1241  * Generate an ISN_PUSHJOB instruction.
1242  * Consumes "job".
1243  */
1244     static int
1245 generate_PUSHJOB(cctx_T *cctx, job_T *job)
1246 {
1247     isn_T	*isn;
1248 
1249     RETURN_OK_IF_SKIP(cctx);
1250     if ((isn = generate_instr_type(cctx, ISN_PUSHJOB, &t_channel)) == NULL)
1251 	return FAIL;
1252     isn->isn_arg.job = job;
1253 
1254     return OK;
1255 }
1256 
1257 /*
1258  * Generate an ISN_PUSHBLOB instruction.
1259  * Consumes "blob".
1260  */
1261     static int
1262 generate_PUSHBLOB(cctx_T *cctx, blob_T *blob)
1263 {
1264     isn_T	*isn;
1265 
1266     RETURN_OK_IF_SKIP(cctx);
1267     if ((isn = generate_instr_type(cctx, ISN_PUSHBLOB, &t_blob)) == NULL)
1268 	return FAIL;
1269     isn->isn_arg.blob = blob;
1270 
1271     return OK;
1272 }
1273 
1274 /*
1275  * Generate an ISN_PUSHFUNC instruction with name "name".
1276  * Consumes "name".
1277  */
1278     static int
1279 generate_PUSHFUNC(cctx_T *cctx, char_u *name, type_T *type)
1280 {
1281     isn_T	*isn;
1282 
1283     RETURN_OK_IF_SKIP(cctx);
1284     if ((isn = generate_instr_type(cctx, ISN_PUSHFUNC, type)) == NULL)
1285 	return FAIL;
1286     isn->isn_arg.string = name == NULL ? NULL : vim_strsave(name);
1287 
1288     return OK;
1289 }
1290 
1291 /*
1292  * Generate an ISN_GETITEM instruction with "index".
1293  * "with_op" is TRUE for "+=" and other operators, the stack has the current
1294  * value below the list with values.
1295  */
1296     static int
1297 generate_GETITEM(cctx_T *cctx, int index, int with_op)
1298 {
1299     isn_T	*isn;
1300     garray_T	*stack = &cctx->ctx_type_stack;
1301     type_T	*type = ((type_T **)stack->ga_data)[stack->ga_len
1302 							  - (with_op ? 2 : 1)];
1303     type_T	*item_type = &t_any;
1304 
1305     RETURN_OK_IF_SKIP(cctx);
1306 
1307     if (type->tt_type != VAR_LIST)
1308     {
1309 	// cannot happen, caller has checked the type
1310 	emsg(_(e_listreq));
1311 	return FAIL;
1312     }
1313     item_type = type->tt_member;
1314     if ((isn = generate_instr(cctx, ISN_GETITEM)) == NULL)
1315 	return FAIL;
1316     isn->isn_arg.getitem.gi_index = index;
1317     isn->isn_arg.getitem.gi_with_op = with_op;
1318 
1319     // add the item type to the type stack
1320     if (GA_GROW_FAILS(stack, 1))
1321 	return FAIL;
1322     ((type_T **)stack->ga_data)[stack->ga_len] = item_type;
1323     ++stack->ga_len;
1324     return OK;
1325 }
1326 
1327 /*
1328  * Generate an ISN_SLICE instruction with "count".
1329  */
1330     static int
1331 generate_SLICE(cctx_T *cctx, int count)
1332 {
1333     isn_T	*isn;
1334 
1335     RETURN_OK_IF_SKIP(cctx);
1336     if ((isn = generate_instr(cctx, ISN_SLICE)) == NULL)
1337 	return FAIL;
1338     isn->isn_arg.number = count;
1339     return OK;
1340 }
1341 
1342 /*
1343  * Generate an ISN_CHECKLEN instruction with "min_len".
1344  */
1345     static int
1346 generate_CHECKLEN(cctx_T *cctx, int min_len, int more_OK)
1347 {
1348     isn_T	*isn;
1349 
1350     RETURN_OK_IF_SKIP(cctx);
1351 
1352     if ((isn = generate_instr(cctx, ISN_CHECKLEN)) == NULL)
1353 	return FAIL;
1354     isn->isn_arg.checklen.cl_min_len = min_len;
1355     isn->isn_arg.checklen.cl_more_OK = more_OK;
1356 
1357     return OK;
1358 }
1359 
1360 /*
1361  * Generate an ISN_STORE instruction.
1362  */
1363     static int
1364 generate_STORE(cctx_T *cctx, isntype_T isn_type, int idx, char_u *name)
1365 {
1366     isn_T	*isn;
1367 
1368     RETURN_OK_IF_SKIP(cctx);
1369     if ((isn = generate_instr_drop(cctx, isn_type, 1)) == NULL)
1370 	return FAIL;
1371     if (name != NULL)
1372 	isn->isn_arg.string = vim_strsave(name);
1373     else
1374 	isn->isn_arg.number = idx;
1375 
1376     return OK;
1377 }
1378 
1379 /*
1380  * Generate an ISN_STOREOUTER instruction.
1381  */
1382     static int
1383 generate_STOREOUTER(cctx_T *cctx, int idx, int level)
1384 {
1385     isn_T	*isn;
1386 
1387     RETURN_OK_IF_SKIP(cctx);
1388     if ((isn = generate_instr_drop(cctx, ISN_STOREOUTER, 1)) == NULL)
1389 	return FAIL;
1390     isn->isn_arg.outer.outer_idx = idx;
1391     isn->isn_arg.outer.outer_depth = level;
1392 
1393     return OK;
1394 }
1395 
1396 /*
1397  * Generate an ISN_STORENR instruction (short for ISN_PUSHNR + ISN_STORE)
1398  */
1399     static int
1400 generate_STORENR(cctx_T *cctx, int idx, varnumber_T value)
1401 {
1402     isn_T	*isn;
1403 
1404     RETURN_OK_IF_SKIP(cctx);
1405     if ((isn = generate_instr(cctx, ISN_STORENR)) == NULL)
1406 	return FAIL;
1407     isn->isn_arg.storenr.stnr_idx = idx;
1408     isn->isn_arg.storenr.stnr_val = value;
1409 
1410     return OK;
1411 }
1412 
1413 /*
1414  * Generate an ISN_STOREOPT instruction
1415  */
1416     static int
1417 generate_STOREOPT(cctx_T *cctx, char_u *name, int opt_flags)
1418 {
1419     isn_T	*isn;
1420 
1421     RETURN_OK_IF_SKIP(cctx);
1422     if ((isn = generate_instr_drop(cctx, ISN_STOREOPT, 1)) == NULL)
1423 	return FAIL;
1424     isn->isn_arg.storeopt.so_name = vim_strsave(name);
1425     isn->isn_arg.storeopt.so_flags = opt_flags;
1426 
1427     return OK;
1428 }
1429 
1430 /*
1431  * Generate an ISN_LOAD or similar instruction.
1432  */
1433     static int
1434 generate_LOAD(
1435 	cctx_T	    *cctx,
1436 	isntype_T   isn_type,
1437 	int	    idx,
1438 	char_u	    *name,
1439 	type_T	    *type)
1440 {
1441     isn_T	*isn;
1442 
1443     RETURN_OK_IF_SKIP(cctx);
1444     if ((isn = generate_instr_type(cctx, isn_type, type)) == NULL)
1445 	return FAIL;
1446     if (name != NULL)
1447 	isn->isn_arg.string = vim_strsave(name);
1448     else
1449 	isn->isn_arg.number = idx;
1450 
1451     return OK;
1452 }
1453 
1454 /*
1455  * Generate an ISN_LOADOUTER instruction
1456  */
1457     static int
1458 generate_LOADOUTER(
1459 	cctx_T	    *cctx,
1460 	int	    idx,
1461 	int	    nesting,
1462 	type_T	    *type)
1463 {
1464     isn_T	*isn;
1465 
1466     RETURN_OK_IF_SKIP(cctx);
1467     if ((isn = generate_instr_type(cctx, ISN_LOADOUTER, type)) == NULL)
1468 	return FAIL;
1469     isn->isn_arg.outer.outer_idx = idx;
1470     isn->isn_arg.outer.outer_depth = nesting;
1471 
1472     return OK;
1473 }
1474 
1475 /*
1476  * Generate an ISN_LOADV instruction for v:var.
1477  */
1478     static int
1479 generate_LOADV(
1480 	cctx_T	    *cctx,
1481 	char_u	    *name,
1482 	int	    error)
1483 {
1484     int	    di_flags;
1485     int	    vidx = find_vim_var(name, &di_flags);
1486     type_T  *type;
1487 
1488     RETURN_OK_IF_SKIP(cctx);
1489     if (vidx < 0)
1490     {
1491 	if (error)
1492 	    semsg(_(e_variable_not_found_str), name);
1493 	return FAIL;
1494     }
1495     type = typval2type_vimvar(get_vim_var_tv(vidx), cctx->ctx_type_list);
1496 
1497     return generate_LOAD(cctx, ISN_LOADV, vidx, NULL, type);
1498 }
1499 
1500 /*
1501  * Generate an ISN_UNLET instruction.
1502  */
1503     static int
1504 generate_UNLET(cctx_T *cctx, isntype_T isn_type, char_u *name, int forceit)
1505 {
1506     isn_T	*isn;
1507 
1508     RETURN_OK_IF_SKIP(cctx);
1509     if ((isn = generate_instr(cctx, isn_type)) == NULL)
1510 	return FAIL;
1511     isn->isn_arg.unlet.ul_name = vim_strsave(name);
1512     isn->isn_arg.unlet.ul_forceit = forceit;
1513 
1514     return OK;
1515 }
1516 
1517 /*
1518  * Generate an ISN_LOCKCONST instruction.
1519  */
1520     static int
1521 generate_LOCKCONST(cctx_T *cctx)
1522 {
1523     isn_T	*isn;
1524 
1525     RETURN_OK_IF_SKIP(cctx);
1526     if ((isn = generate_instr(cctx, ISN_LOCKCONST)) == NULL)
1527 	return FAIL;
1528     return OK;
1529 }
1530 
1531 /*
1532  * Generate an ISN_LOADS instruction.
1533  */
1534     static int
1535 generate_OLDSCRIPT(
1536 	cctx_T	    *cctx,
1537 	isntype_T   isn_type,
1538 	char_u	    *name,
1539 	int	    sid,
1540 	type_T	    *type)
1541 {
1542     isn_T	*isn;
1543 
1544     RETURN_OK_IF_SKIP(cctx);
1545     if (isn_type == ISN_LOADS)
1546 	isn = generate_instr_type(cctx, isn_type, type);
1547     else
1548 	isn = generate_instr_drop(cctx, isn_type, 1);
1549     if (isn == NULL)
1550 	return FAIL;
1551     isn->isn_arg.loadstore.ls_name = vim_strsave(name);
1552     isn->isn_arg.loadstore.ls_sid = sid;
1553 
1554     return OK;
1555 }
1556 
1557 /*
1558  * Generate an ISN_LOADSCRIPT or ISN_STORESCRIPT instruction.
1559  */
1560     static int
1561 generate_VIM9SCRIPT(
1562 	cctx_T	    *cctx,
1563 	isntype_T   isn_type,
1564 	int	    sid,
1565 	int	    idx,
1566 	type_T	    *type)
1567 {
1568     isn_T	*isn;
1569     scriptref_T	*sref;
1570     scriptitem_T *si = SCRIPT_ITEM(sid);
1571 
1572     RETURN_OK_IF_SKIP(cctx);
1573     if (isn_type == ISN_LOADSCRIPT)
1574 	isn = generate_instr_type(cctx, isn_type, type);
1575     else
1576 	isn = generate_instr_drop(cctx, isn_type, 1);
1577     if (isn == NULL)
1578 	return FAIL;
1579 
1580     // This requires three arguments, which doesn't fit in an instruction, thus
1581     // we need to allocate a struct for this.
1582     sref = ALLOC_ONE(scriptref_T);
1583     if (sref == NULL)
1584 	return FAIL;
1585     isn->isn_arg.script.scriptref = sref;
1586     sref->sref_sid = sid;
1587     sref->sref_idx = idx;
1588     sref->sref_seq = si->sn_script_seq;
1589     sref->sref_type = type;
1590     return OK;
1591 }
1592 
1593 /*
1594  * Generate an ISN_NEWLIST instruction.
1595  */
1596     static int
1597 generate_NEWLIST(cctx_T *cctx, int count)
1598 {
1599     isn_T	*isn;
1600     garray_T	*stack = &cctx->ctx_type_stack;
1601     type_T	*type;
1602     type_T	*member;
1603 
1604     RETURN_OK_IF_SKIP(cctx);
1605     if ((isn = generate_instr(cctx, ISN_NEWLIST)) == NULL)
1606 	return FAIL;
1607     isn->isn_arg.number = count;
1608 
1609     // get the member type from all the items on the stack.
1610     if (count == 0)
1611 	member = &t_unknown;
1612     else
1613 	member = get_member_type_from_stack(
1614 	    ((type_T **)stack->ga_data) + stack->ga_len, count, 1,
1615 							  cctx->ctx_type_list);
1616     type = get_list_type(member, cctx->ctx_type_list);
1617 
1618     // drop the value types
1619     stack->ga_len -= count;
1620 
1621     // add the list type to the type stack
1622     if (GA_GROW_FAILS(stack, 1))
1623 	return FAIL;
1624     ((type_T **)stack->ga_data)[stack->ga_len] = type;
1625     ++stack->ga_len;
1626 
1627     return OK;
1628 }
1629 
1630 /*
1631  * Generate an ISN_NEWDICT instruction.
1632  */
1633     static int
1634 generate_NEWDICT(cctx_T *cctx, int count)
1635 {
1636     isn_T	*isn;
1637     garray_T	*stack = &cctx->ctx_type_stack;
1638     type_T	*type;
1639     type_T	*member;
1640 
1641     RETURN_OK_IF_SKIP(cctx);
1642     if ((isn = generate_instr(cctx, ISN_NEWDICT)) == NULL)
1643 	return FAIL;
1644     isn->isn_arg.number = count;
1645 
1646     if (count == 0)
1647 	member = &t_void;
1648     else
1649 	member = get_member_type_from_stack(
1650 	    ((type_T **)stack->ga_data) + stack->ga_len, count, 2,
1651 							  cctx->ctx_type_list);
1652     type = get_dict_type(member, cctx->ctx_type_list);
1653 
1654     // drop the key and value types
1655     stack->ga_len -= 2 * count;
1656 
1657     // add the dict type to the type stack
1658     if (GA_GROW_FAILS(stack, 1))
1659 	return FAIL;
1660     ((type_T **)stack->ga_data)[stack->ga_len] = type;
1661     ++stack->ga_len;
1662 
1663     return OK;
1664 }
1665 
1666 /*
1667  * Generate an ISN_FUNCREF instruction.
1668  */
1669     static int
1670 generate_FUNCREF(cctx_T *cctx, ufunc_T *ufunc)
1671 {
1672     isn_T	*isn;
1673     garray_T	*stack = &cctx->ctx_type_stack;
1674 
1675     RETURN_OK_IF_SKIP(cctx);
1676     if ((isn = generate_instr(cctx, ISN_FUNCREF)) == NULL)
1677 	return FAIL;
1678     isn->isn_arg.funcref.fr_func = ufunc->uf_dfunc_idx;
1679     cctx->ctx_has_closure = 1;
1680 
1681     // If the referenced function is a closure, it may use items further up in
1682     // the nested context, including this one.
1683     if (ufunc->uf_flags & FC_CLOSURE)
1684 	cctx->ctx_ufunc->uf_flags |= FC_CLOSURE;
1685 
1686     if (GA_GROW_FAILS(stack, 1))
1687 	return FAIL;
1688     ((type_T **)stack->ga_data)[stack->ga_len] =
1689 	       ufunc->uf_func_type == NULL ? &t_func_any : ufunc->uf_func_type;
1690     ++stack->ga_len;
1691 
1692     return OK;
1693 }
1694 
1695 /*
1696  * Generate an ISN_NEWFUNC instruction.
1697  * "lambda_name" and "func_name" must be in allocated memory and will be
1698  * consumed.
1699  */
1700     static int
1701 generate_NEWFUNC(cctx_T *cctx, char_u *lambda_name, char_u *func_name)
1702 {
1703     isn_T	*isn;
1704 
1705     if (cctx->ctx_skip == SKIP_YES)
1706     {
1707 	vim_free(lambda_name);
1708 	vim_free(func_name);
1709 	return OK;
1710     }
1711     if ((isn = generate_instr(cctx, ISN_NEWFUNC)) == NULL)
1712     {
1713 	vim_free(lambda_name);
1714 	vim_free(func_name);
1715 	return FAIL;
1716     }
1717     isn->isn_arg.newfunc.nf_lambda = lambda_name;
1718     isn->isn_arg.newfunc.nf_global = func_name;
1719 
1720     return OK;
1721 }
1722 
1723 /*
1724  * Generate an ISN_DEF instruction: list functions
1725  */
1726     static int
1727 generate_DEF(cctx_T *cctx, char_u *name, size_t len)
1728 {
1729     isn_T	*isn;
1730 
1731     RETURN_OK_IF_SKIP(cctx);
1732     if ((isn = generate_instr(cctx, ISN_DEF)) == NULL)
1733 	return FAIL;
1734     if (len > 0)
1735     {
1736 	isn->isn_arg.string = vim_strnsave(name, len);
1737 	if (isn->isn_arg.string == NULL)
1738 	    return FAIL;
1739     }
1740     return OK;
1741 }
1742 
1743 /*
1744  * Generate an ISN_JUMP instruction.
1745  */
1746     static int
1747 generate_JUMP(cctx_T *cctx, jumpwhen_T when, int where)
1748 {
1749     isn_T	*isn;
1750     garray_T	*stack = &cctx->ctx_type_stack;
1751 
1752     RETURN_OK_IF_SKIP(cctx);
1753     if ((isn = generate_instr(cctx, ISN_JUMP)) == NULL)
1754 	return FAIL;
1755     isn->isn_arg.jump.jump_when = when;
1756     isn->isn_arg.jump.jump_where = where;
1757 
1758     if (when != JUMP_ALWAYS && stack->ga_len > 0)
1759 	--stack->ga_len;
1760 
1761     return OK;
1762 }
1763 
1764 /*
1765  * Generate an ISN_JUMP_IF_ARG_SET instruction.
1766  */
1767     static int
1768 generate_JUMP_IF_ARG_SET(cctx_T *cctx, int arg_off)
1769 {
1770     isn_T	*isn;
1771 
1772     RETURN_OK_IF_SKIP(cctx);
1773     if ((isn = generate_instr(cctx, ISN_JUMP_IF_ARG_SET)) == NULL)
1774 	return FAIL;
1775     isn->isn_arg.jumparg.jump_arg_off = arg_off;
1776     // jump_where is set later
1777     return OK;
1778 }
1779 
1780     static int
1781 generate_FOR(cctx_T *cctx, int loop_idx)
1782 {
1783     isn_T	*isn;
1784     garray_T	*stack = &cctx->ctx_type_stack;
1785 
1786     RETURN_OK_IF_SKIP(cctx);
1787     if ((isn = generate_instr(cctx, ISN_FOR)) == NULL)
1788 	return FAIL;
1789     isn->isn_arg.forloop.for_idx = loop_idx;
1790 
1791     if (GA_GROW_FAILS(stack, 1))
1792 	return FAIL;
1793     // type doesn't matter, will be stored next
1794     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
1795     ++stack->ga_len;
1796 
1797     return OK;
1798 }
1799 /*
1800  * Generate an ISN_TRYCONT instruction.
1801  */
1802     static int
1803 generate_TRYCONT(cctx_T *cctx, int levels, int where)
1804 {
1805     isn_T	*isn;
1806 
1807     RETURN_OK_IF_SKIP(cctx);
1808     if ((isn = generate_instr(cctx, ISN_TRYCONT)) == NULL)
1809 	return FAIL;
1810     isn->isn_arg.trycont.tct_levels = levels;
1811     isn->isn_arg.trycont.tct_where = where;
1812 
1813     return OK;
1814 }
1815 
1816 
1817 /*
1818  * Generate an ISN_BCALL instruction.
1819  * "method_call" is TRUE for "value->method()"
1820  * Return FAIL if the number of arguments is wrong.
1821  */
1822     static int
1823 generate_BCALL(cctx_T *cctx, int func_idx, int argcount, int method_call)
1824 {
1825     isn_T	*isn;
1826     garray_T	*stack = &cctx->ctx_type_stack;
1827     int		argoff;
1828     type_T	**argtypes = NULL;
1829     type_T	*shuffled_argtypes[MAX_FUNC_ARGS];
1830     type_T	*maptype = NULL;
1831 
1832     RETURN_OK_IF_SKIP(cctx);
1833     argoff = check_internal_func(func_idx, argcount);
1834     if (argoff < 0)
1835 	return FAIL;
1836 
1837     if (method_call && argoff > 1)
1838     {
1839 	if ((isn = generate_instr(cctx, ISN_SHUFFLE)) == NULL)
1840 	    return FAIL;
1841 	isn->isn_arg.shuffle.shfl_item = argcount;
1842 	isn->isn_arg.shuffle.shfl_up = argoff - 1;
1843     }
1844 
1845     if (argcount > 0)
1846     {
1847 	// Check the types of the arguments.
1848 	argtypes = ((type_T **)stack->ga_data) + stack->ga_len - argcount;
1849 	if (method_call && argoff > 1)
1850 	{
1851 	    int i;
1852 
1853 	    for (i = 0; i < argcount; ++i)
1854 		shuffled_argtypes[i] = (i < argoff - 1)
1855 			    ? argtypes[i + 1]
1856 			    : (i == argoff - 1) ? argtypes[0] : argtypes[i];
1857 	    argtypes = shuffled_argtypes;
1858 	}
1859 	if (internal_func_check_arg_types(argtypes, func_idx, argcount,
1860 								 cctx) == FAIL)
1861 	    return FAIL;
1862 	if (internal_func_is_map(func_idx))
1863 	    maptype = *argtypes;
1864     }
1865 
1866     if ((isn = generate_instr(cctx, ISN_BCALL)) == NULL)
1867 	return FAIL;
1868     isn->isn_arg.bfunc.cbf_idx = func_idx;
1869     isn->isn_arg.bfunc.cbf_argcount = argcount;
1870 
1871     // Drop the argument types and push the return type.
1872     stack->ga_len -= argcount;
1873     if (GA_GROW_FAILS(stack, 1))
1874 	return FAIL;
1875     ((type_T **)stack->ga_data)[stack->ga_len] =
1876 			  internal_func_ret_type(func_idx, argcount, argtypes);
1877     ++stack->ga_len;
1878 
1879     if (maptype != NULL && maptype->tt_member != NULL
1880 					       && maptype->tt_member != &t_any)
1881 	// Check that map() didn't change the item types.
1882 	generate_TYPECHECK(cctx, maptype, -1, 1);
1883 
1884     return OK;
1885 }
1886 
1887 /*
1888  * Generate an ISN_LISTAPPEND instruction.  Works like add().
1889  * Argument count is already checked.
1890  */
1891     static int
1892 generate_LISTAPPEND(cctx_T *cctx)
1893 {
1894     garray_T	*stack = &cctx->ctx_type_stack;
1895     type_T	*list_type;
1896     type_T	*item_type;
1897     type_T	*expected;
1898 
1899     // Caller already checked that list_type is a list.
1900     list_type = ((type_T **)stack->ga_data)[stack->ga_len - 2];
1901     item_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1902     expected = list_type->tt_member;
1903     if (need_type(item_type, expected, -1, 0, cctx, FALSE, FALSE) == FAIL)
1904 	return FAIL;
1905 
1906     if (generate_instr(cctx, ISN_LISTAPPEND) == NULL)
1907 	return FAIL;
1908 
1909     --stack->ga_len;	    // drop the argument
1910     return OK;
1911 }
1912 
1913 /*
1914  * Generate an ISN_BLOBAPPEND instruction.  Works like add().
1915  * Argument count is already checked.
1916  */
1917     static int
1918 generate_BLOBAPPEND(cctx_T *cctx)
1919 {
1920     garray_T	*stack = &cctx->ctx_type_stack;
1921     type_T	*item_type;
1922 
1923     // Caller already checked that blob_type is a blob.
1924     item_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1925     if (need_type(item_type, &t_number, -1, 0, cctx, FALSE, FALSE) == FAIL)
1926 	return FAIL;
1927 
1928     if (generate_instr(cctx, ISN_BLOBAPPEND) == NULL)
1929 	return FAIL;
1930 
1931     --stack->ga_len;	    // drop the argument
1932     return OK;
1933 }
1934 
1935 /*
1936  * Return TRUE if "ufunc" should be compiled, taking into account whether
1937  * "profile" indicates profiling is to be done.
1938  */
1939     int
1940 func_needs_compiling(ufunc_T *ufunc, compiletype_T compile_type)
1941 {
1942     switch (ufunc->uf_def_status)
1943     {
1944 	case UF_TO_BE_COMPILED:
1945 	    return TRUE;
1946 
1947 	case UF_COMPILED:
1948 	{
1949 	    dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
1950 							 + ufunc->uf_dfunc_idx;
1951 
1952 	    switch (compile_type)
1953 	    {
1954 		case CT_PROFILE:
1955 #ifdef FEAT_PROFILE
1956 		    return dfunc->df_instr_prof == NULL;
1957 #endif
1958 		case CT_NONE:
1959 		    return dfunc->df_instr == NULL;
1960 		case CT_DEBUG:
1961 		    return dfunc->df_instr_debug == NULL;
1962 	    }
1963 	}
1964 
1965 	case UF_NOT_COMPILED:
1966 	case UF_COMPILE_ERROR:
1967 	case UF_COMPILING:
1968 	    break;
1969     }
1970     return FALSE;
1971 }
1972 
1973 /*
1974  * Generate an ISN_DCALL or ISN_UCALL instruction.
1975  * Return FAIL if the number of arguments is wrong.
1976  */
1977     static int
1978 generate_CALL(cctx_T *cctx, ufunc_T *ufunc, int pushed_argcount)
1979 {
1980     isn_T	*isn;
1981     garray_T	*stack = &cctx->ctx_type_stack;
1982     int		regular_args = ufunc->uf_args.ga_len;
1983     int		argcount = pushed_argcount;
1984 
1985     RETURN_OK_IF_SKIP(cctx);
1986     if (argcount > regular_args && !has_varargs(ufunc))
1987     {
1988 	semsg(_(e_toomanyarg), printable_func_name(ufunc));
1989 	return FAIL;
1990     }
1991     if (argcount < regular_args - ufunc->uf_def_args.ga_len)
1992     {
1993 	semsg(_(e_toofewarg), printable_func_name(ufunc));
1994 	return FAIL;
1995     }
1996 
1997     if (ufunc->uf_def_status != UF_NOT_COMPILED
1998 	    && ufunc->uf_def_status != UF_COMPILE_ERROR)
1999     {
2000 	int		i;
2001 
2002 	for (i = 0; i < argcount; ++i)
2003 	{
2004 	    type_T *expected;
2005 	    type_T *actual;
2006 
2007 	    actual = ((type_T **)stack->ga_data)[stack->ga_len - argcount + i];
2008 	    if (actual == &t_special
2009 			      && i >= regular_args - ufunc->uf_def_args.ga_len)
2010 	    {
2011 		// assume v:none used for default argument value
2012 		continue;
2013 	    }
2014 	    if (i < regular_args)
2015 	    {
2016 		if (ufunc->uf_arg_types == NULL)
2017 		    continue;
2018 		expected = ufunc->uf_arg_types[i];
2019 	    }
2020 	    else if (ufunc->uf_va_type == NULL
2021 					   || ufunc->uf_va_type == &t_list_any)
2022 		// possibly a lambda or "...: any"
2023 		expected = &t_any;
2024 	    else
2025 		expected = ufunc->uf_va_type->tt_member;
2026 	    if (need_type(actual, expected, -argcount + i, i + 1, cctx,
2027 							  TRUE, FALSE) == FAIL)
2028 	    {
2029 		arg_type_mismatch(expected, actual, i + 1);
2030 		return FAIL;
2031 	    }
2032 	}
2033 	if (func_needs_compiling(ufunc, COMPILE_TYPE(ufunc))
2034 		&& compile_def_function(ufunc, ufunc->uf_ret_type == NULL,
2035 					    COMPILE_TYPE(ufunc), NULL) == FAIL)
2036 	    return FAIL;
2037     }
2038     if (ufunc->uf_def_status == UF_COMPILE_ERROR)
2039     {
2040 	emsg_funcname(_(e_call_to_function_that_failed_to_compile_str),
2041 							       ufunc->uf_name);
2042 	return FAIL;
2043     }
2044 
2045     if ((isn = generate_instr(cctx,
2046 		    ufunc->uf_def_status != UF_NOT_COMPILED ? ISN_DCALL
2047 							 : ISN_UCALL)) == NULL)
2048 	return FAIL;
2049     if (isn->isn_type == ISN_DCALL)
2050     {
2051 	isn->isn_arg.dfunc.cdf_idx = ufunc->uf_dfunc_idx;
2052 	isn->isn_arg.dfunc.cdf_argcount = argcount;
2053     }
2054     else
2055     {
2056 	// A user function may be deleted and redefined later, can't use the
2057 	// ufunc pointer, need to look it up again at runtime.
2058 	isn->isn_arg.ufunc.cuf_name = vim_strsave(ufunc->uf_name);
2059 	isn->isn_arg.ufunc.cuf_argcount = argcount;
2060     }
2061 
2062     stack->ga_len -= argcount; // drop the arguments
2063     if (GA_GROW_FAILS(stack, 1))
2064 	return FAIL;
2065     // add return value
2066     ((type_T **)stack->ga_data)[stack->ga_len] = ufunc->uf_ret_type;
2067     ++stack->ga_len;
2068 
2069     return OK;
2070 }
2071 
2072 /*
2073  * Generate an ISN_UCALL instruction when the function isn't defined yet.
2074  */
2075     static int
2076 generate_UCALL(cctx_T *cctx, char_u *name, int argcount)
2077 {
2078     isn_T	*isn;
2079     garray_T	*stack = &cctx->ctx_type_stack;
2080 
2081     RETURN_OK_IF_SKIP(cctx);
2082     if ((isn = generate_instr(cctx, ISN_UCALL)) == NULL)
2083 	return FAIL;
2084     isn->isn_arg.ufunc.cuf_name = vim_strsave(name);
2085     isn->isn_arg.ufunc.cuf_argcount = argcount;
2086 
2087     stack->ga_len -= argcount; // drop the arguments
2088     if (GA_GROW_FAILS(stack, 1))
2089 	return FAIL;
2090     // add return value
2091     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
2092     ++stack->ga_len;
2093 
2094     return OK;
2095 }
2096 
2097 /*
2098  * Generate an ISN_PCALL instruction.
2099  * "type" is the type of the FuncRef.
2100  */
2101     static int
2102 generate_PCALL(
2103 	cctx_T	*cctx,
2104 	int	argcount,
2105 	char_u	*name,
2106 	type_T	*type,
2107 	int	at_top)
2108 {
2109     isn_T	*isn;
2110     garray_T	*stack = &cctx->ctx_type_stack;
2111     type_T	*ret_type;
2112 
2113     RETURN_OK_IF_SKIP(cctx);
2114 
2115     if (type->tt_type == VAR_ANY)
2116 	ret_type = &t_any;
2117     else if (type->tt_type == VAR_FUNC || type->tt_type == VAR_PARTIAL)
2118     {
2119 	if (type->tt_argcount != -1)
2120 	{
2121 	    int	    varargs = (type->tt_flags & TTFLAG_VARARGS) ? 1 : 0;
2122 
2123 	    if (argcount < type->tt_min_argcount - varargs)
2124 	    {
2125 		semsg(_(e_toofewarg), name);
2126 		return FAIL;
2127 	    }
2128 	    if (!varargs && argcount > type->tt_argcount)
2129 	    {
2130 		semsg(_(e_toomanyarg), name);
2131 		return FAIL;
2132 	    }
2133 	    if (type->tt_args != NULL)
2134 	    {
2135 		int i;
2136 
2137 		for (i = 0; i < argcount; ++i)
2138 		{
2139 		    int	    offset = -argcount + i - (at_top ? 0 : 1);
2140 		    type_T *actual = ((type_T **)stack->ga_data)[
2141 						       stack->ga_len + offset];
2142 		    type_T *expected;
2143 
2144 		    if (varargs && i >= type->tt_argcount - 1)
2145 			expected = type->tt_args[
2146 					     type->tt_argcount - 1]->tt_member;
2147 		    else if (i >= type->tt_min_argcount
2148 						       && actual == &t_special)
2149 			expected = &t_any;
2150 		    else
2151 			expected = type->tt_args[i];
2152 		    if (need_type(actual, expected, offset, i + 1,
2153 						    cctx, TRUE, FALSE) == FAIL)
2154 		    {
2155 			arg_type_mismatch(expected, actual, i + 1);
2156 			return FAIL;
2157 		    }
2158 		}
2159 	    }
2160 	}
2161 	ret_type = type->tt_member;
2162 	if (ret_type == &t_unknown)
2163 	    // return type not known yet, use a runtime check
2164 	    ret_type = &t_any;
2165     }
2166     else
2167     {
2168 	semsg(_(e_not_callable_type_str), name);
2169 	return FAIL;
2170     }
2171 
2172     if ((isn = generate_instr(cctx, ISN_PCALL)) == NULL)
2173 	return FAIL;
2174     isn->isn_arg.pfunc.cpf_top = at_top;
2175     isn->isn_arg.pfunc.cpf_argcount = argcount;
2176 
2177     stack->ga_len -= argcount; // drop the arguments
2178 
2179     // drop the funcref/partial, get back the return value
2180     ((type_T **)stack->ga_data)[stack->ga_len - 1] = ret_type;
2181 
2182     // If partial is above the arguments it must be cleared and replaced with
2183     // the return value.
2184     if (at_top && generate_instr(cctx, ISN_PCALL_END) == NULL)
2185 	return FAIL;
2186 
2187     return OK;
2188 }
2189 
2190 /*
2191  * Generate an ISN_STRINGMEMBER instruction.
2192  */
2193     static int
2194 generate_STRINGMEMBER(cctx_T *cctx, char_u *name, size_t len)
2195 {
2196     isn_T	*isn;
2197     garray_T	*stack = &cctx->ctx_type_stack;
2198     type_T	*type;
2199 
2200     RETURN_OK_IF_SKIP(cctx);
2201     if ((isn = generate_instr(cctx, ISN_STRINGMEMBER)) == NULL)
2202 	return FAIL;
2203     isn->isn_arg.string = vim_strnsave(name, len);
2204 
2205     // check for dict type
2206     type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
2207     if (type->tt_type != VAR_DICT && type != &t_any)
2208     {
2209 	char *tofree;
2210 
2211 	semsg(_(e_expected_dictionary_for_using_key_str_but_got_str),
2212 					       name, type_name(type, &tofree));
2213 	vim_free(tofree);
2214 	return FAIL;
2215     }
2216     // change dict type to dict member type
2217     if (type->tt_type == VAR_DICT)
2218     {
2219 	((type_T **)stack->ga_data)[stack->ga_len - 1] =
2220 		      type->tt_member == &t_unknown ? &t_any : type->tt_member;
2221     }
2222 
2223     return OK;
2224 }
2225 
2226 /*
2227  * Generate an ISN_ECHO instruction.
2228  */
2229     static int
2230 generate_ECHO(cctx_T *cctx, int with_white, int count)
2231 {
2232     isn_T	*isn;
2233 
2234     RETURN_OK_IF_SKIP(cctx);
2235     if ((isn = generate_instr_drop(cctx, ISN_ECHO, count)) == NULL)
2236 	return FAIL;
2237     isn->isn_arg.echo.echo_with_white = with_white;
2238     isn->isn_arg.echo.echo_count = count;
2239 
2240     return OK;
2241 }
2242 
2243 /*
2244  * Generate an ISN_EXECUTE/ISN_ECHOMSG/ISN_ECHOERR instruction.
2245  */
2246     static int
2247 generate_MULT_EXPR(cctx_T *cctx, isntype_T isn_type, int count)
2248 {
2249     isn_T	*isn;
2250 
2251     if ((isn = generate_instr_drop(cctx, isn_type, count)) == NULL)
2252 	return FAIL;
2253     isn->isn_arg.number = count;
2254 
2255     return OK;
2256 }
2257 
2258 /*
2259  * Generate an ISN_PUT instruction.
2260  */
2261     static int
2262 generate_PUT(cctx_T *cctx, int regname, linenr_T lnum)
2263 {
2264     isn_T	*isn;
2265 
2266     RETURN_OK_IF_SKIP(cctx);
2267     if ((isn = generate_instr(cctx, ISN_PUT)) == NULL)
2268 	return FAIL;
2269     isn->isn_arg.put.put_regname = regname;
2270     isn->isn_arg.put.put_lnum = lnum;
2271     return OK;
2272 }
2273 
2274     static int
2275 generate_EXEC(cctx_T *cctx, isntype_T isntype, char_u *line)
2276 {
2277     isn_T	*isn;
2278 
2279     RETURN_OK_IF_SKIP(cctx);
2280     if ((isn = generate_instr(cctx, isntype)) == NULL)
2281 	return FAIL;
2282     isn->isn_arg.string = vim_strsave(line);
2283     return OK;
2284 }
2285 
2286     static int
2287 generate_LEGACY_EVAL(cctx_T *cctx, char_u *line)
2288 {
2289     isn_T	*isn;
2290     garray_T	*stack = &cctx->ctx_type_stack;
2291 
2292     RETURN_OK_IF_SKIP(cctx);
2293     if ((isn = generate_instr(cctx, ISN_LEGACY_EVAL)) == NULL)
2294 	return FAIL;
2295     isn->isn_arg.string = vim_strsave(line);
2296 
2297     if (GA_GROW_FAILS(stack, 1))
2298 	return FAIL;
2299     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
2300     ++stack->ga_len;
2301 
2302     return OK;
2303 }
2304 
2305     static int
2306 generate_EXECCONCAT(cctx_T *cctx, int count)
2307 {
2308     isn_T	*isn;
2309 
2310     if ((isn = generate_instr_drop(cctx, ISN_EXECCONCAT, count)) == NULL)
2311 	return FAIL;
2312     isn->isn_arg.number = count;
2313     return OK;
2314 }
2315 
2316 /*
2317  * Generate ISN_RANGE.  Consumes "range".  Return OK/FAIL.
2318  */
2319     static int
2320 generate_RANGE(cctx_T *cctx, char_u *range)
2321 {
2322     isn_T	*isn;
2323     garray_T	*stack = &cctx->ctx_type_stack;
2324 
2325     if ((isn = generate_instr(cctx, ISN_RANGE)) == NULL)
2326 	return FAIL;
2327     isn->isn_arg.string = range;
2328 
2329     if (GA_GROW_FAILS(stack, 1))
2330 	return FAIL;
2331     ((type_T **)stack->ga_data)[stack->ga_len] = &t_number;
2332     ++stack->ga_len;
2333     return OK;
2334 }
2335 
2336     static int
2337 generate_UNPACK(cctx_T *cctx, int var_count, int semicolon)
2338 {
2339     isn_T	*isn;
2340 
2341     RETURN_OK_IF_SKIP(cctx);
2342     if ((isn = generate_instr(cctx, ISN_UNPACK)) == NULL)
2343 	return FAIL;
2344     isn->isn_arg.unpack.unp_count = var_count;
2345     isn->isn_arg.unpack.unp_semicolon = semicolon;
2346     return OK;
2347 }
2348 
2349 /*
2350  * Generate an instruction for any command modifiers.
2351  */
2352     static int
2353 generate_cmdmods(cctx_T *cctx, cmdmod_T *cmod)
2354 {
2355     isn_T	*isn;
2356 
2357     if (has_cmdmod(cmod, FALSE))
2358     {
2359 	cctx->ctx_has_cmdmod = TRUE;
2360 
2361 	if ((isn = generate_instr(cctx, ISN_CMDMOD)) == NULL)
2362 	    return FAIL;
2363 	isn->isn_arg.cmdmod.cf_cmdmod = ALLOC_ONE(cmdmod_T);
2364 	if (isn->isn_arg.cmdmod.cf_cmdmod == NULL)
2365 	    return FAIL;
2366 	mch_memmove(isn->isn_arg.cmdmod.cf_cmdmod, cmod, sizeof(cmdmod_T));
2367 	// filter program now belongs to the instruction
2368 	cmod->cmod_filter_regmatch.regprog = NULL;
2369     }
2370 
2371     return OK;
2372 }
2373 
2374     static int
2375 generate_undo_cmdmods(cctx_T *cctx)
2376 {
2377     if (cctx->ctx_has_cmdmod && generate_instr(cctx, ISN_CMDMOD_REV) == NULL)
2378 	return FAIL;
2379     cctx->ctx_has_cmdmod = FALSE;
2380     return OK;
2381 }
2382 
2383     static int
2384 misplaced_cmdmod(cctx_T *cctx)
2385 {
2386     garray_T	*instr = &cctx->ctx_instr;
2387 
2388     if (cctx->ctx_has_cmdmod
2389 	    && ((isn_T *)instr->ga_data)[instr->ga_len - 1].isn_type
2390 								 == ISN_CMDMOD)
2391     {
2392 	emsg(_(e_misplaced_command_modifier));
2393 	return TRUE;
2394     }
2395     return FALSE;
2396 }
2397 
2398 /*
2399  * Get the index of the current instruction.
2400  * This compensates for a preceding ISN_CMDMOD and ISN_PROF_START.
2401  */
2402     static int
2403 current_instr_idx(cctx_T *cctx)
2404 {
2405     garray_T	*instr = &cctx->ctx_instr;
2406     int		idx = instr->ga_len;
2407 
2408     while (idx > 0)
2409     {
2410 	if (cctx->ctx_has_cmdmod && ((isn_T *)instr->ga_data)[idx - 1]
2411 						       .isn_type == ISN_CMDMOD)
2412 	{
2413 	    --idx;
2414 	    continue;
2415 	}
2416 #ifdef FEAT_PROFILE
2417 	if (((isn_T *)instr->ga_data)[idx - 1].isn_type == ISN_PROF_START)
2418 	{
2419 	    --idx;
2420 	    continue;
2421 	}
2422 #endif
2423 	if (((isn_T *)instr->ga_data)[idx - 1].isn_type == ISN_DEBUG)
2424 	{
2425 	    --idx;
2426 	    continue;
2427 	}
2428 	break;
2429     }
2430     return idx;
2431 }
2432 
2433 #ifdef FEAT_PROFILE
2434     static void
2435 may_generate_prof_end(cctx_T *cctx, int prof_lnum)
2436 {
2437     if (cctx->ctx_compile_type == CT_PROFILE && prof_lnum >= 0)
2438 	generate_instr(cctx, ISN_PROF_END);
2439 }
2440 #endif
2441 
2442 /*
2443  * Reserve space for a local variable.
2444  * Return the variable or NULL if it failed.
2445  */
2446     static lvar_T *
2447 reserve_local(
2448 	cctx_T	*cctx,
2449 	char_u	*name,
2450 	size_t	len,
2451 	int	isConst,
2452 	type_T	*type)
2453 {
2454     lvar_T  *lvar;
2455     dfunc_T *dfunc;
2456 
2457     if (arg_exists(name, len, NULL, NULL, NULL, cctx) == OK)
2458     {
2459 	emsg_namelen(_(e_str_is_used_as_argument), name, (int)len);
2460 	return NULL;
2461     }
2462 
2463     if (GA_GROW_FAILS(&cctx->ctx_locals, 1))
2464 	return NULL;
2465     lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + cctx->ctx_locals.ga_len++;
2466     CLEAR_POINTER(lvar);
2467 
2468     // Every local variable uses the next entry on the stack.  We could re-use
2469     // the last ones when leaving a scope, but then variables used in a closure
2470     // might get overwritten.  To keep things simple do not re-use stack
2471     // entries.  This is less efficient, but memory is cheap these days.
2472     dfunc = ((dfunc_T *)def_functions.ga_data) + cctx->ctx_ufunc->uf_dfunc_idx;
2473     lvar->lv_idx = dfunc->df_var_names.ga_len;
2474 
2475     lvar->lv_name = vim_strnsave(name, len == 0 ? STRLEN(name) : len);
2476     lvar->lv_const = isConst;
2477     lvar->lv_type = type;
2478 
2479     // Remember the name for debugging.
2480     if (GA_GROW_FAILS(&dfunc->df_var_names, 1))
2481 	return NULL;
2482     ((char_u **)dfunc->df_var_names.ga_data)[lvar->lv_idx] =
2483 						    vim_strsave(lvar->lv_name);
2484     ++dfunc->df_var_names.ga_len;
2485 
2486     return lvar;
2487 }
2488 
2489 /*
2490  * Remove local variables above "new_top".
2491  */
2492     static void
2493 unwind_locals(cctx_T *cctx, int new_top)
2494 {
2495     if (cctx->ctx_locals.ga_len > new_top)
2496     {
2497 	int	idx;
2498 	lvar_T	*lvar;
2499 
2500 	for (idx = new_top; idx < cctx->ctx_locals.ga_len; ++idx)
2501 	{
2502 	    lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + idx;
2503 	    vim_free(lvar->lv_name);
2504 	}
2505     }
2506     cctx->ctx_locals.ga_len = new_top;
2507 }
2508 
2509 /*
2510  * Free all local variables.
2511  */
2512     static void
2513 free_locals(cctx_T *cctx)
2514 {
2515     unwind_locals(cctx, 0);
2516     ga_clear(&cctx->ctx_locals);
2517 }
2518 
2519 /*
2520  * If "check_writable" is ASSIGN_CONST give an error if the variable was
2521  * defined with :final or :const, if "check_writable" is ASSIGN_FINAL give an
2522  * error if the variable was defined with :const.
2523  */
2524     static int
2525 check_item_writable(svar_T *sv, int check_writable, char_u *name)
2526 {
2527     if ((check_writable == ASSIGN_CONST && sv->sv_const != 0)
2528 	    || (check_writable == ASSIGN_FINAL
2529 					      && sv->sv_const == ASSIGN_CONST))
2530     {
2531 	semsg(_(e_cannot_change_readonly_variable_str), name);
2532 	return FAIL;
2533     }
2534     return OK;
2535 }
2536 
2537 /*
2538  * Find "name" in script-local items of script "sid".
2539  * Pass "check_writable" to check_item_writable().
2540  * Returns the index in "sn_var_vals" if found.
2541  * If found but not in "sn_var_vals" returns -1.
2542  * If not found or the variable is not writable returns -2.
2543  */
2544     int
2545 get_script_item_idx(int sid, char_u *name, int check_writable, cctx_T *cctx)
2546 {
2547     hashtab_T	    *ht;
2548     dictitem_T	    *di;
2549     scriptitem_T    *si = SCRIPT_ITEM(sid);
2550     svar_T	    *sv;
2551     int		    idx;
2552 
2553     if (!SCRIPT_ID_VALID(sid))
2554 	return -1;
2555     if (sid == current_sctx.sc_sid)
2556     {
2557 	sallvar_T *sav = find_script_var(name, 0, cctx);
2558 
2559 	if (sav == NULL)
2560 	    return -2;
2561 	idx = sav->sav_var_vals_idx;
2562 	sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
2563 	if (check_item_writable(sv, check_writable, name) == FAIL)
2564 	    return -2;
2565 	return idx;
2566     }
2567 
2568     // First look the name up in the hashtable.
2569     ht = &SCRIPT_VARS(sid);
2570     di = find_var_in_ht(ht, 0, name, TRUE);
2571     if (di == NULL)
2572 	return -2;
2573 
2574     // Now find the svar_T index in sn_var_vals.
2575     for (idx = 0; idx < si->sn_var_vals.ga_len; ++idx)
2576     {
2577 	sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
2578 	if (sv->sv_tv == &di->di_tv)
2579 	{
2580 	    if (check_item_writable(sv, check_writable, name) == FAIL)
2581 		return -2;
2582 	    return idx;
2583 	}
2584     }
2585     return -1;
2586 }
2587 
2588 /*
2589  * Find "name" in imported items of the current script or in "cctx" if not
2590  * NULL.
2591  */
2592     imported_T *
2593 find_imported(char_u *name, size_t len, cctx_T *cctx)
2594 {
2595     int		    idx;
2596 
2597     if (!SCRIPT_ID_VALID(current_sctx.sc_sid))
2598 	return NULL;
2599     if (cctx != NULL)
2600 	for (idx = 0; idx < cctx->ctx_imports.ga_len; ++idx)
2601 	{
2602 	    imported_T *import = ((imported_T *)cctx->ctx_imports.ga_data)
2603 									 + idx;
2604 
2605 	    if (len == 0 ? STRCMP(name, import->imp_name) == 0
2606 			 : STRLEN(import->imp_name) == len
2607 				  && STRNCMP(name, import->imp_name, len) == 0)
2608 		return import;
2609 	}
2610 
2611     return find_imported_in_script(name, len, current_sctx.sc_sid);
2612 }
2613 
2614     imported_T *
2615 find_imported_in_script(char_u *name, size_t len, int sid)
2616 {
2617     scriptitem_T    *si;
2618     int		    idx;
2619 
2620     if (!SCRIPT_ID_VALID(sid))
2621 	return NULL;
2622     si = SCRIPT_ITEM(sid);
2623     for (idx = 0; idx < si->sn_imports.ga_len; ++idx)
2624     {
2625 	imported_T *import = ((imported_T *)si->sn_imports.ga_data) + idx;
2626 
2627 	if (len == 0 ? STRCMP(name, import->imp_name) == 0
2628 		     : STRLEN(import->imp_name) == len
2629 				  && STRNCMP(name, import->imp_name, len) == 0)
2630 	    return import;
2631     }
2632     return NULL;
2633 }
2634 
2635 /*
2636  * Free all imported variables.
2637  */
2638     static void
2639 free_imported(cctx_T *cctx)
2640 {
2641     int idx;
2642 
2643     for (idx = 0; idx < cctx->ctx_imports.ga_len; ++idx)
2644     {
2645 	imported_T *import = ((imported_T *)cctx->ctx_imports.ga_data) + idx;
2646 
2647 	vim_free(import->imp_name);
2648     }
2649     ga_clear(&cctx->ctx_imports);
2650 }
2651 
2652 /*
2653  * Return a pointer to the next line that isn't empty or only contains a
2654  * comment. Skips over white space.
2655  * Returns NULL if there is none.
2656  */
2657     char_u *
2658 peek_next_line_from_context(cctx_T *cctx)
2659 {
2660     int lnum = cctx->ctx_lnum;
2661 
2662     while (++lnum < cctx->ctx_ufunc->uf_lines.ga_len)
2663     {
2664 	char_u *line = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[lnum];
2665 	char_u *p;
2666 
2667 	// ignore NULLs inserted for continuation lines
2668 	if (line != NULL)
2669 	{
2670 	    p = skipwhite(line);
2671 	    if (vim9_bad_comment(p))
2672 		return NULL;
2673 	    if (*p != NUL && !vim9_comment_start(p))
2674 		return p;
2675 	}
2676     }
2677     return NULL;
2678 }
2679 
2680 /*
2681  * Called when checking for a following operator at "arg".  When the rest of
2682  * the line is empty or only a comment, peek the next line.  If there is a next
2683  * line return a pointer to it and set "nextp".
2684  * Otherwise skip over white space.
2685  */
2686     static char_u *
2687 may_peek_next_line(cctx_T *cctx, char_u *arg, char_u **nextp)
2688 {
2689     char_u *p = skipwhite(arg);
2690 
2691     *nextp = NULL;
2692     if (*p == NUL || (VIM_ISWHITE(*arg) && vim9_comment_start(p)))
2693     {
2694 	*nextp = peek_next_line_from_context(cctx);
2695 	if (*nextp != NULL)
2696 	    return *nextp;
2697     }
2698     return p;
2699 }
2700 
2701 /*
2702  * Get the next line of the function from "cctx".
2703  * Skips over empty lines.  Skips over comment lines if "skip_comment" is TRUE.
2704  * Returns NULL when at the end.
2705  */
2706     char_u *
2707 next_line_from_context(cctx_T *cctx, int skip_comment)
2708 {
2709     char_u	*line;
2710 
2711     do
2712     {
2713 	++cctx->ctx_lnum;
2714 	if (cctx->ctx_lnum >= cctx->ctx_ufunc->uf_lines.ga_len)
2715 	{
2716 	    line = NULL;
2717 	    break;
2718 	}
2719 	line = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum];
2720 	cctx->ctx_line_start = line;
2721 	SOURCING_LNUM = cctx->ctx_lnum + 1;
2722     } while (line == NULL || *skipwhite(line) == NUL
2723 		     || (skip_comment && vim9_comment_start(skipwhite(line))));
2724     return line;
2725 }
2726 
2727 /*
2728  * Skip over white space at "whitep" and assign to "*arg".
2729  * If "*arg" is at the end of the line, advance to the next line.
2730  * Also when "whitep" points to white space and "*arg" is on a "#".
2731  * Return FAIL if beyond the last line, "*arg" is unmodified then.
2732  */
2733     static int
2734 may_get_next_line(char_u *whitep, char_u **arg, cctx_T *cctx)
2735 {
2736     *arg = skipwhite(whitep);
2737     if (vim9_bad_comment(*arg))
2738 	return FAIL;
2739     if (**arg == NUL || (VIM_ISWHITE(*whitep) && vim9_comment_start(*arg)))
2740     {
2741 	char_u *next = next_line_from_context(cctx, TRUE);
2742 
2743 	if (next == NULL)
2744 	    return FAIL;
2745 	*arg = skipwhite(next);
2746     }
2747     return OK;
2748 }
2749 
2750 /*
2751  * Idem, and give an error when failed.
2752  */
2753     static int
2754 may_get_next_line_error(char_u *whitep, char_u **arg, cctx_T *cctx)
2755 {
2756     if (may_get_next_line(whitep, arg, cctx) == FAIL)
2757     {
2758 	SOURCING_LNUM = cctx->ctx_lnum + 1;
2759 	emsg(_(e_line_incomplete));
2760 	return FAIL;
2761     }
2762     return OK;
2763 }
2764 
2765 
2766 // Structure passed between the compile_expr* functions to keep track of
2767 // constants that have been parsed but for which no code was produced yet.  If
2768 // possible expressions on these constants are applied at compile time.  If
2769 // that is not possible, the code to push the constants needs to be generated
2770 // before other instructions.
2771 // Using 50 should be more than enough of 5 levels of ().
2772 #define PPSIZE 50
2773 typedef struct {
2774     typval_T	pp_tv[PPSIZE];	// stack of ppconst constants
2775     int		pp_used;	// active entries in pp_tv[]
2776     int		pp_is_const;	// all generated code was constants, used for a
2777 				// list or dict with constant members
2778 } ppconst_T;
2779 
2780 static int compile_expr0_ext(char_u **arg,  cctx_T *cctx, int *is_const);
2781 static int compile_expr0(char_u **arg,  cctx_T *cctx);
2782 static int compile_expr1(char_u **arg,  cctx_T *cctx, ppconst_T *ppconst);
2783 
2784 /*
2785  * Generate a PUSH instruction for "tv".
2786  * "tv" will be consumed or cleared.
2787  * Nothing happens if "tv" is NULL or of type VAR_UNKNOWN;
2788  */
2789     static int
2790 generate_tv_PUSH(cctx_T *cctx, typval_T *tv)
2791 {
2792     if (tv != NULL)
2793     {
2794 	switch (tv->v_type)
2795 	{
2796 	    case VAR_UNKNOWN:
2797 		break;
2798 	    case VAR_BOOL:
2799 		generate_PUSHBOOL(cctx, tv->vval.v_number);
2800 		break;
2801 	    case VAR_SPECIAL:
2802 		generate_PUSHSPEC(cctx, tv->vval.v_number);
2803 		break;
2804 	    case VAR_NUMBER:
2805 		generate_PUSHNR(cctx, tv->vval.v_number);
2806 		break;
2807 #ifdef FEAT_FLOAT
2808 	    case VAR_FLOAT:
2809 		generate_PUSHF(cctx, tv->vval.v_float);
2810 		break;
2811 #endif
2812 	    case VAR_BLOB:
2813 		generate_PUSHBLOB(cctx, tv->vval.v_blob);
2814 		tv->vval.v_blob = NULL;
2815 		break;
2816 	    case VAR_STRING:
2817 		generate_PUSHS(cctx, &tv->vval.v_string);
2818 		tv->vval.v_string = NULL;
2819 		break;
2820 	    default:
2821 		iemsg("constant type not supported");
2822 		clear_tv(tv);
2823 		return FAIL;
2824 	}
2825 	tv->v_type = VAR_UNKNOWN;
2826     }
2827     return OK;
2828 }
2829 
2830 /*
2831  * Generate code for any ppconst entries.
2832  */
2833     static int
2834 generate_ppconst(cctx_T *cctx, ppconst_T *ppconst)
2835 {
2836     int	    i;
2837     int	    ret = OK;
2838     int	    save_skip = cctx->ctx_skip;
2839 
2840     cctx->ctx_skip = SKIP_NOT;
2841     for (i = 0; i < ppconst->pp_used; ++i)
2842 	if (generate_tv_PUSH(cctx, &ppconst->pp_tv[i]) == FAIL)
2843 	    ret = FAIL;
2844     ppconst->pp_used = 0;
2845     cctx->ctx_skip = save_skip;
2846     return ret;
2847 }
2848 
2849 /*
2850  * Check that the last item of "ppconst" is a bool.
2851  */
2852     static int
2853 check_ppconst_bool(ppconst_T *ppconst)
2854 {
2855     if (ppconst->pp_used > 0)
2856     {
2857 	typval_T    *tv = &ppconst->pp_tv[ppconst->pp_used - 1];
2858 	where_T	    where = WHERE_INIT;
2859 
2860 	return check_typval_type(&t_bool, tv, where);
2861     }
2862     return OK;
2863 }
2864 
2865 /*
2866  * Clear ppconst constants.  Used when failing.
2867  */
2868     static void
2869 clear_ppconst(ppconst_T *ppconst)
2870 {
2871     int	    i;
2872 
2873     for (i = 0; i < ppconst->pp_used; ++i)
2874 	clear_tv(&ppconst->pp_tv[i]);
2875     ppconst->pp_used = 0;
2876 }
2877 
2878 /*
2879  * Compile getting a member from a list/dict/string/blob.  Stack has the
2880  * indexable value and the index or the two indexes of a slice.
2881  */
2882     static int
2883 compile_member(int is_slice, cctx_T *cctx)
2884 {
2885     type_T	**typep;
2886     garray_T	*stack = &cctx->ctx_type_stack;
2887     vartype_T	vartype;
2888     type_T	*idxtype;
2889 
2890     // We can index a list, dict and blob.  If we don't know the type
2891     // we can use the index value type.  If we still don't know use an "ANY"
2892     // instruction.
2893     typep = ((type_T **)stack->ga_data) + stack->ga_len
2894 						  - (is_slice ? 3 : 2);
2895     vartype = (*typep)->tt_type;
2896     idxtype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
2897     // If the index is a string, the variable must be a Dict.
2898     if (*typep == &t_any && idxtype == &t_string)
2899 	vartype = VAR_DICT;
2900     if (vartype == VAR_STRING || vartype == VAR_LIST || vartype == VAR_BLOB)
2901     {
2902 	if (need_type(idxtype, &t_number, -1, 0, cctx, FALSE, FALSE) == FAIL)
2903 	    return FAIL;
2904 	if (is_slice)
2905 	{
2906 	    idxtype = ((type_T **)stack->ga_data)[stack->ga_len - 2];
2907 	    if (need_type(idxtype, &t_number, -2, 0, cctx,
2908 							 FALSE, FALSE) == FAIL)
2909 		return FAIL;
2910 	}
2911     }
2912 
2913     if (vartype == VAR_DICT)
2914     {
2915 	if (is_slice)
2916 	{
2917 	    emsg(_(e_cannot_slice_dictionary));
2918 	    return FAIL;
2919 	}
2920 	if ((*typep)->tt_type == VAR_DICT)
2921 	{
2922 	    *typep = (*typep)->tt_member;
2923 	    if (*typep == &t_unknown)
2924 		// empty dict was used
2925 		*typep = &t_any;
2926 	}
2927 	else
2928 	{
2929 	    if (need_type(*typep, &t_dict_any, -2, 0, cctx,
2930 							 FALSE, FALSE) == FAIL)
2931 		return FAIL;
2932 	    *typep = &t_any;
2933 	}
2934 	if (may_generate_2STRING(-1, FALSE, cctx) == FAIL)
2935 	    return FAIL;
2936 	if (generate_instr_drop(cctx, ISN_MEMBER, 1) == FAIL)
2937 	    return FAIL;
2938     }
2939     else if (vartype == VAR_STRING)
2940     {
2941 	*typep = &t_string;
2942 	if ((is_slice
2943 		? generate_instr_drop(cctx, ISN_STRSLICE, 2)
2944 		: generate_instr_drop(cctx, ISN_STRINDEX, 1)) == FAIL)
2945 	    return FAIL;
2946     }
2947     else if (vartype == VAR_BLOB)
2948     {
2949 	if (is_slice)
2950 	{
2951 	    *typep = &t_blob;
2952 	    if (generate_instr_drop(cctx, ISN_BLOBSLICE, 2) == FAIL)
2953 		return FAIL;
2954 	}
2955 	else
2956 	{
2957 	    *typep = &t_number;
2958 	    if (generate_instr_drop(cctx, ISN_BLOBINDEX, 1) == FAIL)
2959 		return FAIL;
2960 	}
2961     }
2962     else if (vartype == VAR_LIST || *typep == &t_any)
2963     {
2964 	if (is_slice)
2965 	{
2966 	    if (generate_instr_drop(cctx,
2967 		     vartype == VAR_LIST ?  ISN_LISTSLICE : ISN_ANYSLICE,
2968 							    2) == FAIL)
2969 		return FAIL;
2970 	}
2971 	else
2972 	{
2973 	    if ((*typep)->tt_type == VAR_LIST)
2974 	    {
2975 		*typep = (*typep)->tt_member;
2976 		if (*typep == &t_unknown)
2977 		    // empty list was used
2978 		    *typep = &t_any;
2979 	    }
2980 	    if (generate_instr_drop(cctx,
2981 			vartype == VAR_LIST ?  ISN_LISTINDEX : ISN_ANYINDEX, 1)
2982 								       == FAIL)
2983 		return FAIL;
2984 	}
2985     }
2986     else
2987     {
2988 	emsg(_(e_string_list_dict_or_blob_required));
2989 	return FAIL;
2990     }
2991     return OK;
2992 }
2993 
2994 /*
2995  * Generate an instruction to load script-local variable "name", without the
2996  * leading "s:".
2997  * Also finds imported variables.
2998  */
2999     static int
3000 compile_load_scriptvar(
3001 	cctx_T *cctx,
3002 	char_u *name,	    // variable NUL terminated
3003 	char_u *start,	    // start of variable
3004 	char_u **end,	    // end of variable
3005 	int    error)	    // when TRUE may give error
3006 {
3007     scriptitem_T    *si;
3008     int		    idx;
3009     imported_T	    *import;
3010 
3011     if (!SCRIPT_ID_VALID(current_sctx.sc_sid))
3012 	return FAIL;
3013     si = SCRIPT_ITEM(current_sctx.sc_sid);
3014     idx = get_script_item_idx(current_sctx.sc_sid, name, 0, cctx);
3015     if (idx == -1 || si->sn_version != SCRIPT_VERSION_VIM9)
3016     {
3017 	// variable is not in sn_var_vals: old style script.
3018 	return generate_OLDSCRIPT(cctx, ISN_LOADS, name, current_sctx.sc_sid,
3019 								       &t_any);
3020     }
3021     if (idx >= 0)
3022     {
3023 	svar_T		*sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
3024 
3025 	generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
3026 					current_sctx.sc_sid, idx, sv->sv_type);
3027 	return OK;
3028     }
3029 
3030     import = find_imported(name, 0, cctx);
3031     if (import != NULL)
3032     {
3033 	if (import->imp_flags & IMP_FLAGS_STAR)
3034 	{
3035 	    char_u	*p = skipwhite(*end);
3036 	    char_u	*exp_name;
3037 	    int		cc;
3038 	    ufunc_T	*ufunc;
3039 	    type_T	*type;
3040 
3041 	    // Used "import * as Name", need to lookup the member.
3042 	    if (*p != '.')
3043 	    {
3044 		semsg(_(e_expected_dot_after_name_str), start);
3045 		return FAIL;
3046 	    }
3047 	    ++p;
3048 	    if (VIM_ISWHITE(*p))
3049 	    {
3050 		emsg(_(e_no_white_space_allowed_after_dot));
3051 		return FAIL;
3052 	    }
3053 
3054 	    // isolate one name
3055 	    exp_name = p;
3056 	    while (eval_isnamec(*p))
3057 		++p;
3058 	    cc = *p;
3059 	    *p = NUL;
3060 
3061 	    idx = find_exported(import->imp_sid, exp_name, &ufunc, &type,
3062 								   cctx, TRUE);
3063 	    *p = cc;
3064 	    p = skipwhite(p);
3065 	    *end = p;
3066 
3067 	    if (idx < 0)
3068 	    {
3069 		if (*p == '(' && ufunc != NULL)
3070 		{
3071 		    generate_PUSHFUNC(cctx, ufunc->uf_name, import->imp_type);
3072 		    return OK;
3073 		}
3074 		return FAIL;
3075 	    }
3076 
3077 	    generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
3078 		    import->imp_sid,
3079 		    idx,
3080 		    type);
3081 	}
3082 	else if (import->imp_funcname != NULL)
3083 	    generate_PUSHFUNC(cctx, import->imp_funcname, import->imp_type);
3084 	else
3085 	    generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
3086 		    import->imp_sid,
3087 		    import->imp_var_vals_idx,
3088 		    import->imp_type);
3089 	return OK;
3090     }
3091 
3092     if (error)
3093 	semsg(_(e_item_not_found_str), name);
3094     return FAIL;
3095 }
3096 
3097     static int
3098 generate_funcref(cctx_T *cctx, char_u *name)
3099 {
3100     ufunc_T *ufunc = find_func(name, FALSE, cctx);
3101 
3102     if (ufunc == NULL)
3103 	return FAIL;
3104 
3105     // Need to compile any default values to get the argument types.
3106     if (func_needs_compiling(ufunc, COMPILE_TYPE(ufunc))
3107 	    && compile_def_function(ufunc, TRUE, COMPILE_TYPE(ufunc), NULL)
3108 								       == FAIL)
3109 	return FAIL;
3110     return generate_PUSHFUNC(cctx, ufunc->uf_name, ufunc->uf_func_type);
3111 }
3112 
3113 /*
3114  * Compile a variable name into a load instruction.
3115  * "end" points to just after the name.
3116  * "is_expr" is TRUE when evaluating an expression, might be a funcref.
3117  * When "error" is FALSE do not give an error when not found.
3118  */
3119     static int
3120 compile_load(
3121 	char_u **arg,
3122 	char_u *end_arg,
3123 	cctx_T	*cctx,
3124 	int	is_expr,
3125 	int	error)
3126 {
3127     type_T	*type;
3128     char_u	*name = NULL;
3129     char_u	*end = end_arg;
3130     int		res = FAIL;
3131     int		prev_called_emsg = called_emsg;
3132 
3133     if (*(*arg + 1) == ':')
3134     {
3135 	if (end <= *arg + 2)
3136 	{
3137 	    isntype_T  isn_type;
3138 
3139 	    // load dictionary of namespace
3140 	    switch (**arg)
3141 	    {
3142 		case 'g': isn_type = ISN_LOADGDICT; break;
3143 		case 'w': isn_type = ISN_LOADWDICT; break;
3144 		case 't': isn_type = ISN_LOADTDICT; break;
3145 		case 'b': isn_type = ISN_LOADBDICT; break;
3146 		default:
3147 		    semsg(_(e_namespace_not_supported_str), *arg);
3148 		    goto theend;
3149 	    }
3150 	    if (generate_instr_type(cctx, isn_type, &t_dict_any) == NULL)
3151 		goto theend;
3152 	    res = OK;
3153 	}
3154 	else
3155 	{
3156 	    isntype_T  isn_type = ISN_DROP;
3157 
3158 	    // load namespaced variable
3159 	    name = vim_strnsave(*arg + 2, end - (*arg + 2));
3160 	    if (name == NULL)
3161 		return FAIL;
3162 
3163 	    switch (**arg)
3164 	    {
3165 		case 'v': res = generate_LOADV(cctx, name, error);
3166 			  break;
3167 		case 's': if (is_expr && ASCII_ISUPPER(*name)
3168 				       && find_func(name, FALSE, cctx) != NULL)
3169 			      res = generate_funcref(cctx, name);
3170 			  else
3171 			      res = compile_load_scriptvar(cctx, name,
3172 							    NULL, &end, error);
3173 			  break;
3174 		case 'g': if (vim_strchr(name, AUTOLOAD_CHAR) == NULL)
3175 			  {
3176 			      if (is_expr && ASCII_ISUPPER(*name)
3177 				       && find_func(name, FALSE, cctx) != NULL)
3178 				  res = generate_funcref(cctx, name);
3179 			      else
3180 				  isn_type = ISN_LOADG;
3181 			  }
3182 			  else
3183 			  {
3184 			      isn_type = ISN_LOADAUTO;
3185 			      vim_free(name);
3186 			      name = vim_strnsave(*arg, end - *arg);
3187 			      if (name == NULL)
3188 				  return FAIL;
3189 			  }
3190 			  break;
3191 		case 'w': isn_type = ISN_LOADW; break;
3192 		case 't': isn_type = ISN_LOADT; break;
3193 		case 'b': isn_type = ISN_LOADB; break;
3194 		default:  // cannot happen, just in case
3195 			  semsg(_(e_namespace_not_supported_str), *arg);
3196 			  goto theend;
3197 	    }
3198 	    if (isn_type != ISN_DROP)
3199 	    {
3200 		// Global, Buffer-local, Window-local and Tabpage-local
3201 		// variables can be defined later, thus we don't check if it
3202 		// exists, give an error at runtime.
3203 		res = generate_LOAD(cctx, isn_type, 0, name, &t_any);
3204 	    }
3205 	}
3206     }
3207     else
3208     {
3209 	size_t	    len = end - *arg;
3210 	int	    idx;
3211 	int	    gen_load = FALSE;
3212 	int	    gen_load_outer = 0;
3213 
3214 	name = vim_strnsave(*arg, end - *arg);
3215 	if (name == NULL)
3216 	    return FAIL;
3217 
3218 	if (vim_strchr(name, AUTOLOAD_CHAR) != NULL)
3219 	{
3220 	    script_autoload(name, FALSE);
3221 	    res = generate_LOAD(cctx, ISN_LOADAUTO, 0, name, &t_any);
3222 	}
3223 	else if (arg_exists(*arg, len, &idx, &type, &gen_load_outer, cctx)
3224 									 == OK)
3225 	{
3226 	    if (gen_load_outer == 0)
3227 		gen_load = TRUE;
3228 	}
3229 	else
3230 	{
3231 	    lvar_T lvar;
3232 
3233 	    if (lookup_local(*arg, len, &lvar, cctx) == OK)
3234 	    {
3235 		type = lvar.lv_type;
3236 		idx = lvar.lv_idx;
3237 		if (lvar.lv_from_outer != 0)
3238 		    gen_load_outer = lvar.lv_from_outer;
3239 		else
3240 		    gen_load = TRUE;
3241 	    }
3242 	    else
3243 	    {
3244 		// "var" can be script-local even without using "s:" if it
3245 		// already exists in a Vim9 script or when it's imported.
3246 		if (script_var_exists(*arg, len, cctx) == OK
3247 			|| find_imported(name, 0, cctx) != NULL)
3248 		   res = compile_load_scriptvar(cctx, name, *arg, &end, FALSE);
3249 
3250 		// When evaluating an expression and the name starts with an
3251 		// uppercase letter it can be a user defined function.
3252 		// generate_funcref() will fail if the function can't be found.
3253 		if (res == FAIL && is_expr && ASCII_ISUPPER(*name))
3254 		    res = generate_funcref(cctx, name);
3255 	    }
3256 	}
3257 	if (gen_load)
3258 	    res = generate_LOAD(cctx, ISN_LOAD, idx, NULL, type);
3259 	if (gen_load_outer > 0)
3260 	{
3261 	    res = generate_LOADOUTER(cctx, idx, gen_load_outer, type);
3262 	    cctx->ctx_outer_used = TRUE;
3263 	}
3264     }
3265 
3266     *arg = end;
3267 
3268 theend:
3269     if (res == FAIL && error && called_emsg == prev_called_emsg)
3270 	semsg(_(e_variable_not_found_str), name);
3271     vim_free(name);
3272     return res;
3273 }
3274 
3275     static void
3276 clear_instr_ga(garray_T *gap)
3277 {
3278     int idx;
3279 
3280     for (idx = 0; idx < gap->ga_len; ++idx)
3281 	delete_instr(((isn_T *)gap->ga_data) + idx);
3282     ga_clear(gap);
3283 }
3284 
3285 /*
3286  * Compile a string in a ISN_PUSHS instruction into an ISN_INSTR.
3287  * Returns FAIL if compilation fails.
3288  */
3289     static int
3290 compile_string(isn_T *isn, cctx_T *cctx)
3291 {
3292     char_u	*s = isn->isn_arg.string;
3293     garray_T	save_ga = cctx->ctx_instr;
3294     int		expr_res;
3295     int		trailing_error;
3296     int		instr_count;
3297     isn_T	*instr = NULL;
3298 
3299     // Remove the string type from the stack.
3300     --cctx->ctx_type_stack.ga_len;
3301 
3302     // Temporarily reset the list of instructions so that the jump labels are
3303     // correct.
3304     cctx->ctx_instr.ga_len = 0;
3305     cctx->ctx_instr.ga_maxlen = 0;
3306     cctx->ctx_instr.ga_data = NULL;
3307     expr_res = compile_expr0(&s, cctx);
3308     s = skipwhite(s);
3309     trailing_error = *s != NUL;
3310 
3311     if (expr_res == FAIL || trailing_error
3312 				       || GA_GROW_FAILS(&cctx->ctx_instr, 1))
3313     {
3314 	if (trailing_error)
3315 	    semsg(_(e_trailing_arg), s);
3316 	clear_instr_ga(&cctx->ctx_instr);
3317 	cctx->ctx_instr = save_ga;
3318 	++cctx->ctx_type_stack.ga_len;
3319 	return FAIL;
3320     }
3321 
3322     // Move the generated instructions into the ISN_INSTR instruction, then
3323     // restore the list of instructions.
3324     instr_count = cctx->ctx_instr.ga_len;
3325     instr = cctx->ctx_instr.ga_data;
3326     instr[instr_count].isn_type = ISN_FINISH;
3327 
3328     cctx->ctx_instr = save_ga;
3329     vim_free(isn->isn_arg.string);
3330     isn->isn_type = ISN_INSTR;
3331     isn->isn_arg.instr = instr;
3332     return OK;
3333 }
3334 
3335 /*
3336  * Compile the argument expressions.
3337  * "arg" points to just after the "(" and is advanced to after the ")"
3338  */
3339     static int
3340 compile_arguments(char_u **arg, cctx_T *cctx, int *argcount, int is_searchpair)
3341 {
3342     char_u  *p = *arg;
3343     char_u  *whitep = *arg;
3344     int	    must_end = FALSE;
3345     int	    instr_count;
3346 
3347     for (;;)
3348     {
3349 	if (may_get_next_line(whitep, &p, cctx) == FAIL)
3350 	    goto failret;
3351 	if (*p == ')')
3352 	{
3353 	    *arg = p + 1;
3354 	    return OK;
3355 	}
3356 	if (must_end)
3357 	{
3358 	    semsg(_(e_missing_comma_before_argument_str), p);
3359 	    return FAIL;
3360 	}
3361 
3362 	instr_count = cctx->ctx_instr.ga_len;
3363 	if (compile_expr0(&p, cctx) == FAIL)
3364 	    return FAIL;
3365 	++*argcount;
3366 
3367 	if (is_searchpair && *argcount == 5
3368 		&& cctx->ctx_instr.ga_len == instr_count + 1)
3369 	{
3370 	    isn_T *isn = ((isn_T *)cctx->ctx_instr.ga_data) + instr_count;
3371 
3372 	    // {skip} argument of searchpair() can be compiled if not empty
3373 	    if (isn->isn_type == ISN_PUSHS && *isn->isn_arg.string != NUL)
3374 		compile_string(isn, cctx);
3375 	}
3376 
3377 	if (*p != ',' && *skipwhite(p) == ',')
3378 	{
3379 	    semsg(_(e_no_white_space_allowed_before_str_str), ",", p);
3380 	    p = skipwhite(p);
3381 	}
3382 	if (*p == ',')
3383 	{
3384 	    ++p;
3385 	    if (*p != NUL && !VIM_ISWHITE(*p))
3386 		semsg(_(e_white_space_required_after_str_str), ",", p - 1);
3387 	}
3388 	else
3389 	    must_end = TRUE;
3390 	whitep = p;
3391 	p = skipwhite(p);
3392     }
3393 failret:
3394     emsg(_(e_missing_close));
3395     return FAIL;
3396 }
3397 
3398 /*
3399  * Compile a function call:  name(arg1, arg2)
3400  * "arg" points to "name", "arg + varlen" to the "(".
3401  * "argcount_init" is 1 for "value->method()"
3402  * Instructions:
3403  *	EVAL arg1
3404  *	EVAL arg2
3405  *	BCALL / DCALL / UCALL
3406  */
3407     static int
3408 compile_call(
3409 	char_u	    **arg,
3410 	size_t	    varlen,
3411 	cctx_T	    *cctx,
3412 	ppconst_T   *ppconst,
3413 	int	    argcount_init)
3414 {
3415     char_u	*name = *arg;
3416     char_u	*p;
3417     int		argcount = argcount_init;
3418     char_u	namebuf[100];
3419     char_u	fname_buf[FLEN_FIXED + 1];
3420     char_u	*tofree = NULL;
3421     int		error = FCERR_NONE;
3422     ufunc_T	*ufunc = NULL;
3423     int		res = FAIL;
3424     int		is_autoload;
3425     int		is_searchpair;
3426 
3427     // We can evaluate "has('name')" at compile time.
3428     // We always evaluate "exists_compiled()" at compile time.
3429     if ((varlen == 3 && STRNCMP(*arg, "has", 3) == 0)
3430 	    || (varlen == 15 && STRNCMP(*arg, "exists_compiled", 6) == 0))
3431     {
3432 	char_u	    *s = skipwhite(*arg + varlen + 1);
3433 	typval_T    argvars[2];
3434 	int	    is_has = **arg == 'h';
3435 
3436 	argvars[0].v_type = VAR_UNKNOWN;
3437 	if (*s == '"')
3438 	    (void)eval_string(&s, &argvars[0], TRUE);
3439 	else if (*s == '\'')
3440 	    (void)eval_lit_string(&s, &argvars[0], TRUE);
3441 	s = skipwhite(s);
3442 	if (*s == ')' && argvars[0].v_type == VAR_STRING
3443 	       && ((is_has && !dynamic_feature(argvars[0].vval.v_string))
3444 		    || !is_has))
3445 	{
3446 	    typval_T	*tv = &ppconst->pp_tv[ppconst->pp_used];
3447 
3448 	    *arg = s + 1;
3449 	    argvars[1].v_type = VAR_UNKNOWN;
3450 	    tv->v_type = VAR_NUMBER;
3451 	    tv->vval.v_number = 0;
3452 	    if (is_has)
3453 		f_has(argvars, tv);
3454 	    else
3455 		f_exists(argvars, tv);
3456 	    clear_tv(&argvars[0]);
3457 	    ++ppconst->pp_used;
3458 	    return OK;
3459 	}
3460 	clear_tv(&argvars[0]);
3461 	if (!is_has)
3462 	{
3463 	    emsg(_(e_argument_of_exists_compiled_must_be_literal_string));
3464 	    return FAIL;
3465 	}
3466     }
3467 
3468     if (generate_ppconst(cctx, ppconst) == FAIL)
3469 	return FAIL;
3470 
3471     if (varlen >= sizeof(namebuf))
3472     {
3473 	semsg(_(e_name_too_long_str), name);
3474 	return FAIL;
3475     }
3476     vim_strncpy(namebuf, *arg, varlen);
3477     name = fname_trans_sid(namebuf, fname_buf, &tofree, &error);
3478 
3479     // We handle the "skip" argument of searchpair() and searchpairpos()
3480     // differently.
3481     is_searchpair = (varlen == 6 && STRNCMP(*arg, "search", 6) == 0)
3482 	         || (varlen == 9 && STRNCMP(*arg, "searchpos", 9) == 0)
3483 	        || (varlen == 10 && STRNCMP(*arg, "searchpair", 10) == 0)
3484 	        || (varlen == 13 && STRNCMP(*arg, "searchpairpos", 13) == 0);
3485 
3486     *arg = skipwhite(*arg + varlen + 1);
3487     if (compile_arguments(arg, cctx, &argcount, is_searchpair) == FAIL)
3488 	goto theend;
3489 
3490     is_autoload = vim_strchr(name, AUTOLOAD_CHAR) != NULL;
3491     if (ASCII_ISLOWER(*name) && name[1] != ':' && !is_autoload)
3492     {
3493 	int	    idx;
3494 
3495 	// builtin function
3496 	idx = find_internal_func(name);
3497 	if (idx >= 0)
3498 	{
3499 	    if (STRCMP(name, "flatten") == 0)
3500 	    {
3501 		emsg(_(e_cannot_use_flatten_in_vim9_script));
3502 		goto theend;
3503 	    }
3504 
3505 	    if (STRCMP(name, "add") == 0 && argcount == 2)
3506 	    {
3507 		garray_T    *stack = &cctx->ctx_type_stack;
3508 		type_T	    *type = ((type_T **)stack->ga_data)[
3509 							    stack->ga_len - 2];
3510 
3511 		// add() can be compiled to instructions if we know the type
3512 		if (type->tt_type == VAR_LIST)
3513 		{
3514 		    // inline "add(list, item)" so that the type can be checked
3515 		    res = generate_LISTAPPEND(cctx);
3516 		    idx = -1;
3517 		}
3518 		else if (type->tt_type == VAR_BLOB)
3519 		{
3520 		    // inline "add(blob, nr)" so that the type can be checked
3521 		    res = generate_BLOBAPPEND(cctx);
3522 		    idx = -1;
3523 		}
3524 	    }
3525 
3526 	    if (idx >= 0)
3527 		res = generate_BCALL(cctx, idx, argcount, argcount_init == 1);
3528 	}
3529 	else
3530 	    semsg(_(e_unknownfunc), namebuf);
3531 	goto theend;
3532     }
3533 
3534     // An argument or local variable can be a function reference, this
3535     // overrules a function name.
3536     if (lookup_local(namebuf, varlen, NULL, cctx) == FAIL
3537 	    && arg_exists(namebuf, varlen, NULL, NULL, NULL, cctx) != OK)
3538     {
3539 	// If we can find the function by name generate the right call.
3540 	// Skip global functions here, a local funcref takes precedence.
3541 	ufunc = find_func(name, FALSE, cctx);
3542 	if (ufunc != NULL && !func_is_global(ufunc))
3543 	{
3544 	    res = generate_CALL(cctx, ufunc, argcount);
3545 	    goto theend;
3546 	}
3547     }
3548 
3549     // If the name is a variable, load it and use PCALL.
3550     // Not for g:Func(), we don't know if it is a variable or not.
3551     // Not for eome#Func(), it will be loaded later.
3552     p = namebuf;
3553     if (STRNCMP(namebuf, "g:", 2) != 0 && !is_autoload
3554 	    && compile_load(&p, namebuf + varlen, cctx, FALSE, FALSE) == OK)
3555     {
3556 	garray_T    *stack = &cctx->ctx_type_stack;
3557 	type_T	    *type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
3558 
3559 	res = generate_PCALL(cctx, argcount, namebuf, type, FALSE);
3560 	goto theend;
3561     }
3562 
3563     // If we can find a global function by name generate the right call.
3564     if (ufunc != NULL)
3565     {
3566 	res = generate_CALL(cctx, ufunc, argcount);
3567 	goto theend;
3568     }
3569 
3570     // A global function may be defined only later.  Need to figure out at
3571     // runtime.  Also handles a FuncRef at runtime.
3572     if (STRNCMP(namebuf, "g:", 2) == 0 || is_autoload)
3573 	res = generate_UCALL(cctx, name, argcount);
3574     else
3575 	semsg(_(e_unknownfunc), namebuf);
3576 
3577 theend:
3578     vim_free(tofree);
3579     return res;
3580 }
3581 
3582 // like NAMESPACE_CHAR but with 'a' and 'l'.
3583 #define VIM9_NAMESPACE_CHAR	(char_u *)"bgstvw"
3584 
3585 /*
3586  * Find the end of a variable or function name.  Unlike find_name_end() this
3587  * does not recognize magic braces.
3588  * When "use_namespace" is TRUE recognize "b:", "s:", etc.
3589  * Return a pointer to just after the name.  Equal to "arg" if there is no
3590  * valid name.
3591  */
3592     char_u *
3593 to_name_end(char_u *arg, int use_namespace)
3594 {
3595     char_u	*p;
3596 
3597     // Quick check for valid starting character.
3598     if (!eval_isnamec1(*arg))
3599 	return arg;
3600 
3601     for (p = arg + 1; *p != NUL && eval_isnamec(*p); MB_PTR_ADV(p))
3602 	// Include a namespace such as "s:var" and "v:var".  But "n:" is not
3603 	// and can be used in slice "[n:]".
3604 	if (*p == ':' && (p != arg + 1
3605 			     || !use_namespace
3606 			     || vim_strchr(VIM9_NAMESPACE_CHAR, *arg) == NULL))
3607 	    break;
3608     return p;
3609 }
3610 
3611 /*
3612  * Like to_name_end() but also skip over a list or dict constant.
3613  * Also accept "<SNR>123_Func".
3614  * This intentionally does not handle line continuation.
3615  */
3616     char_u *
3617 to_name_const_end(char_u *arg)
3618 {
3619     char_u	*p = arg;
3620     typval_T	rettv;
3621 
3622     if (STRNCMP(p, "<SNR>", 5) == 0)
3623 	p = skipdigits(p + 5);
3624     p = to_name_end(p, TRUE);
3625     if (p == arg && *arg == '[')
3626     {
3627 
3628 	// Can be "[1, 2, 3]->Func()".
3629 	if (eval_list(&p, &rettv, NULL, FALSE) == FAIL)
3630 	    p = arg;
3631     }
3632     return p;
3633 }
3634 
3635 /*
3636  * parse a list: [expr, expr]
3637  * "*arg" points to the '['.
3638  * ppconst->pp_is_const is set if all items are a constant.
3639  */
3640     static int
3641 compile_list(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3642 {
3643     char_u	*p = skipwhite(*arg + 1);
3644     char_u	*whitep = *arg + 1;
3645     int		count = 0;
3646     int		is_const;
3647     int		is_all_const = TRUE;	// reset when non-const encountered
3648 
3649     for (;;)
3650     {
3651 	if (may_get_next_line(whitep, &p, cctx) == FAIL)
3652 	{
3653 	    semsg(_(e_list_end), *arg);
3654 	    return FAIL;
3655 	}
3656 	if (*p == ',')
3657 	{
3658 	    semsg(_(e_no_white_space_allowed_before_str_str), ",", p);
3659 	    return FAIL;
3660 	}
3661 	if (*p == ']')
3662 	{
3663 	    ++p;
3664 	    break;
3665 	}
3666 	if (compile_expr0_ext(&p, cctx, &is_const) == FAIL)
3667 	    return FAIL;
3668 	if (!is_const)
3669 	    is_all_const = FALSE;
3670 	++count;
3671 	if (*p == ',')
3672 	{
3673 	    ++p;
3674 	    if (*p != ']' && !IS_WHITE_OR_NUL(*p))
3675 	    {
3676 		semsg(_(e_white_space_required_after_str_str), ",", p - 1);
3677 		return FAIL;
3678 	    }
3679 	}
3680 	whitep = p;
3681 	p = skipwhite(p);
3682     }
3683     *arg = p;
3684 
3685     ppconst->pp_is_const = is_all_const;
3686     return generate_NEWLIST(cctx, count);
3687 }
3688 
3689 /*
3690  * Parse a lambda: "(arg, arg) => expr"
3691  * "*arg" points to the '('.
3692  * Returns OK/FAIL when a lambda is recognized, NOTDONE if it's not a lambda.
3693  */
3694     static int
3695 compile_lambda(char_u **arg, cctx_T *cctx)
3696 {
3697     int		r;
3698     typval_T	rettv;
3699     ufunc_T	*ufunc;
3700     evalarg_T	evalarg;
3701 
3702     CLEAR_FIELD(evalarg);
3703     evalarg.eval_flags = EVAL_EVALUATE;
3704     evalarg.eval_cctx = cctx;
3705 
3706     // Get the funcref in "rettv".
3707     r = get_lambda_tv(arg, &rettv, TRUE, &evalarg);
3708     if (r != OK)
3709     {
3710 	clear_evalarg(&evalarg, NULL);
3711 	return r;
3712     }
3713 
3714     // "rettv" will now be a partial referencing the function.
3715     ufunc = rettv.vval.v_partial->pt_func;
3716     ++ufunc->uf_refcount;
3717     clear_tv(&rettv);
3718 
3719     // Compile it here to get the return type.  The return type is optional,
3720     // when it's missing use t_unknown.  This is recognized in
3721     // compile_return().
3722     if (ufunc->uf_ret_type->tt_type == VAR_VOID)
3723 	ufunc->uf_ret_type = &t_unknown;
3724     compile_def_function(ufunc, FALSE, cctx->ctx_compile_type, cctx);
3725 
3726 #ifdef FEAT_PROFILE
3727     // When the outer function is compiled for profiling, the lambda may be
3728     // called without profiling.  Compile it here in the right context.
3729     if (cctx->ctx_compile_type == CT_PROFILE)
3730 	compile_def_function(ufunc, FALSE, CT_NONE, cctx);
3731 #endif
3732 
3733     // evalarg.eval_tofree_cmdline may have a copy of the last line and "*arg"
3734     // points into it.  Point to the original line to avoid a dangling pointer.
3735     if (evalarg.eval_tofree_cmdline != NULL)
3736     {
3737 	size_t	off = *arg - evalarg.eval_tofree_cmdline;
3738 
3739 	*arg = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum]
3740 									 + off;
3741     }
3742 
3743     clear_evalarg(&evalarg, NULL);
3744 
3745     if (ufunc->uf_def_status == UF_COMPILED)
3746     {
3747 	// The return type will now be known.
3748 	set_function_type(ufunc);
3749 
3750 	// The function reference count will be 1.  When the ISN_FUNCREF
3751 	// instruction is deleted the reference count is decremented and the
3752 	// function is freed.
3753 	return generate_FUNCREF(cctx, ufunc);
3754     }
3755 
3756     func_ptr_unref(ufunc);
3757     return FAIL;
3758 }
3759 
3760 /*
3761  * Get a lambda and compile it.  Uses Vim9 syntax.
3762  */
3763     int
3764 get_lambda_tv_and_compile(
3765 	char_u	    **arg,
3766 	typval_T    *rettv,
3767 	int	    types_optional,
3768 	evalarg_T   *evalarg)
3769 {
3770     int		r;
3771     ufunc_T	*ufunc;
3772     int		save_sc_version = current_sctx.sc_version;
3773 
3774     // Get the funcref in "rettv".
3775     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
3776     r = get_lambda_tv(arg, rettv, types_optional, evalarg);
3777     current_sctx.sc_version = save_sc_version;
3778     if (r != OK)
3779 	return r;
3780 
3781     // "rettv" will now be a partial referencing the function.
3782     ufunc = rettv->vval.v_partial->pt_func;
3783 
3784     // Compile it here to get the return type.  The return type is optional,
3785     // when it's missing use t_unknown.  This is recognized in
3786     // compile_return().
3787     if (ufunc->uf_ret_type == NULL || ufunc->uf_ret_type->tt_type == VAR_VOID)
3788 	ufunc->uf_ret_type = &t_unknown;
3789     compile_def_function(ufunc, FALSE, CT_NONE, NULL);
3790 
3791     if (ufunc->uf_def_status == UF_COMPILED)
3792     {
3793 	// The return type will now be known.
3794 	set_function_type(ufunc);
3795 	return OK;
3796     }
3797     clear_tv(rettv);
3798     return FAIL;
3799 }
3800 
3801 /*
3802  * parse a dict: {key: val, [key]: val}
3803  * "*arg" points to the '{'.
3804  * ppconst->pp_is_const is set if all item values are a constant.
3805  */
3806     static int
3807 compile_dict(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3808 {
3809     garray_T	*instr = &cctx->ctx_instr;
3810     int		count = 0;
3811     dict_T	*d = dict_alloc();
3812     dictitem_T	*item;
3813     char_u	*whitep = *arg + 1;
3814     char_u	*p;
3815     int		is_const;
3816     int		is_all_const = TRUE;	// reset when non-const encountered
3817 
3818     if (d == NULL)
3819 	return FAIL;
3820     if (generate_ppconst(cctx, ppconst) == FAIL)
3821 	return FAIL;
3822     for (;;)
3823     {
3824 	char_u	    *key = NULL;
3825 
3826 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
3827 	{
3828 	    *arg = NULL;
3829 	    goto failret;
3830 	}
3831 
3832 	if (**arg == '}')
3833 	    break;
3834 
3835 	if (**arg == '[')
3836 	{
3837 	    isn_T	*isn;
3838 
3839 	    // {[expr]: value} uses an evaluated key.
3840 	    *arg = skipwhite(*arg + 1);
3841 	    if (compile_expr0(arg, cctx) == FAIL)
3842 		return FAIL;
3843 	    isn = ((isn_T *)instr->ga_data) + instr->ga_len - 1;
3844 	    if (isn->isn_type == ISN_PUSHNR)
3845 	    {
3846 		char buf[NUMBUFLEN];
3847 
3848 		// Convert to string at compile time.
3849 		vim_snprintf(buf, NUMBUFLEN, "%lld", isn->isn_arg.number);
3850 		isn->isn_type = ISN_PUSHS;
3851 		isn->isn_arg.string = vim_strsave((char_u *)buf);
3852 	    }
3853 	    if (isn->isn_type == ISN_PUSHS)
3854 		key = isn->isn_arg.string;
3855 	    else if (may_generate_2STRING(-1, FALSE, cctx) == FAIL)
3856 		return FAIL;
3857 	    *arg = skipwhite(*arg);
3858 	    if (**arg != ']')
3859 	    {
3860 		emsg(_(e_missing_matching_bracket_after_dict_key));
3861 		return FAIL;
3862 	    }
3863 	    ++*arg;
3864 	}
3865 	else
3866 	{
3867 	    // {"name": value},
3868 	    // {'name': value},
3869 	    // {name: value} use "name" as a literal key
3870 	    key = get_literal_key(arg);
3871 	    if (key == NULL)
3872 		return FAIL;
3873 	    if (generate_PUSHS(cctx, &key) == FAIL)
3874 		return FAIL;
3875 	}
3876 
3877 	// Check for duplicate keys, if using string keys.
3878 	if (key != NULL)
3879 	{
3880 	    item = dict_find(d, key, -1);
3881 	    if (item != NULL)
3882 	    {
3883 		semsg(_(e_duplicate_key), key);
3884 		goto failret;
3885 	    }
3886 	    item = dictitem_alloc(key);
3887 	    if (item != NULL)
3888 	    {
3889 		item->di_tv.v_type = VAR_UNKNOWN;
3890 		item->di_tv.v_lock = 0;
3891 		if (dict_add(d, item) == FAIL)
3892 		    dictitem_free(item);
3893 	    }
3894 	}
3895 
3896 	if (**arg != ':')
3897 	{
3898 	    if (*skipwhite(*arg) == ':')
3899 		semsg(_(e_no_white_space_allowed_before_str_str), ":", *arg);
3900 	    else
3901 		semsg(_(e_missing_dict_colon), *arg);
3902 	    return FAIL;
3903 	}
3904 	whitep = *arg + 1;
3905 	if (!IS_WHITE_OR_NUL(*whitep))
3906 	{
3907 	    semsg(_(e_white_space_required_after_str_str), ":", *arg);
3908 	    return FAIL;
3909 	}
3910 
3911 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
3912 	{
3913 	    *arg = NULL;
3914 	    goto failret;
3915 	}
3916 
3917 	if (compile_expr0_ext(arg, cctx, &is_const) == FAIL)
3918 	    return FAIL;
3919 	if (!is_const)
3920 	    is_all_const = FALSE;
3921 	++count;
3922 
3923 	whitep = *arg;
3924 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
3925 	{
3926 	    *arg = NULL;
3927 	    goto failret;
3928 	}
3929 	if (**arg == '}')
3930 	    break;
3931 	if (**arg != ',')
3932 	{
3933 	    semsg(_(e_missing_dict_comma), *arg);
3934 	    goto failret;
3935 	}
3936 	if (IS_WHITE_OR_NUL(*whitep))
3937 	{
3938 	    semsg(_(e_no_white_space_allowed_before_str_str), ",", whitep);
3939 	    return FAIL;
3940 	}
3941 	whitep = *arg + 1;
3942 	if (!IS_WHITE_OR_NUL(*whitep))
3943 	{
3944 	    semsg(_(e_white_space_required_after_str_str), ",", *arg);
3945 	    return FAIL;
3946 	}
3947 	*arg = skipwhite(whitep);
3948     }
3949 
3950     *arg = *arg + 1;
3951 
3952     // Allow for following comment, after at least one space.
3953     p = skipwhite(*arg);
3954     if (VIM_ISWHITE(**arg) && vim9_comment_start(p))
3955 	*arg += STRLEN(*arg);
3956 
3957     dict_unref(d);
3958     ppconst->pp_is_const = is_all_const;
3959     return generate_NEWDICT(cctx, count);
3960 
3961 failret:
3962     if (*arg == NULL)
3963     {
3964 	semsg(_(e_missing_dict_end), _("[end of lines]"));
3965 	*arg = (char_u *)"";
3966     }
3967     dict_unref(d);
3968     return FAIL;
3969 }
3970 
3971 /*
3972  * Compile "&option".
3973  */
3974     static int
3975 compile_get_option(char_u **arg, cctx_T *cctx)
3976 {
3977     typval_T	rettv;
3978     char_u	*start = *arg;
3979     int		ret;
3980 
3981     // parse the option and get the current value to get the type.
3982     rettv.v_type = VAR_UNKNOWN;
3983     ret = eval_option(arg, &rettv, TRUE);
3984     if (ret == OK)
3985     {
3986 	// include the '&' in the name, eval_option() expects it.
3987 	char_u	*name = vim_strnsave(start, *arg - start);
3988 	type_T	*type = rettv.v_type == VAR_BOOL ? &t_bool
3989 			  : rettv.v_type == VAR_NUMBER ? &t_number : &t_string;
3990 
3991 	ret = generate_LOAD(cctx, ISN_LOADOPT, 0, name, type);
3992 	vim_free(name);
3993     }
3994     clear_tv(&rettv);
3995 
3996     return ret;
3997 }
3998 
3999 /*
4000  * Compile "$VAR".
4001  */
4002     static int
4003 compile_get_env(char_u **arg, cctx_T *cctx)
4004 {
4005     char_u	*start = *arg;
4006     int		len;
4007     int		ret;
4008     char_u	*name;
4009 
4010     ++*arg;
4011     len = get_env_len(arg);
4012     if (len == 0)
4013     {
4014 	semsg(_(e_syntax_error_at_str), start - 1);
4015 	return FAIL;
4016     }
4017 
4018     // include the '$' in the name, eval_env_var() expects it.
4019     name = vim_strnsave(start, len + 1);
4020     ret = generate_LOAD(cctx, ISN_LOADENV, 0, name, &t_string);
4021     vim_free(name);
4022     return ret;
4023 }
4024 
4025 /*
4026  * Compile "@r".
4027  */
4028     static int
4029 compile_get_register(char_u **arg, cctx_T *cctx)
4030 {
4031     int		ret;
4032 
4033     ++*arg;
4034     if (**arg == NUL)
4035     {
4036 	semsg(_(e_syntax_error_at_str), *arg - 1);
4037 	return FAIL;
4038     }
4039     if (!valid_yank_reg(**arg, FALSE))
4040     {
4041 	emsg_invreg(**arg);
4042 	return FAIL;
4043     }
4044     ret = generate_LOAD(cctx, ISN_LOADREG, **arg, NULL, &t_string);
4045     ++*arg;
4046     return ret;
4047 }
4048 
4049 /*
4050  * Apply leading '!', '-' and '+' to constant "rettv".
4051  * When "numeric_only" is TRUE do not apply '!'.
4052  */
4053     static int
4054 apply_leader(typval_T *rettv, int numeric_only, char_u *start, char_u **end)
4055 {
4056     char_u *p = *end;
4057 
4058     // this works from end to start
4059     while (p > start)
4060     {
4061 	--p;
4062 	if (*p == '-' || *p == '+')
4063 	{
4064 	    // only '-' has an effect, for '+' we only check the type
4065 #ifdef FEAT_FLOAT
4066 	    if (rettv->v_type == VAR_FLOAT)
4067 	    {
4068 		if (*p == '-')
4069 		    rettv->vval.v_float = -rettv->vval.v_float;
4070 	    }
4071 	    else
4072 #endif
4073 	    {
4074 		varnumber_T	val;
4075 		int		error = FALSE;
4076 
4077 		// tv_get_number_chk() accepts a string, but we don't want that
4078 		// here
4079 		if (check_not_string(rettv) == FAIL)
4080 		    return FAIL;
4081 		val = tv_get_number_chk(rettv, &error);
4082 		clear_tv(rettv);
4083 		if (error)
4084 		    return FAIL;
4085 		if (*p == '-')
4086 		    val = -val;
4087 		rettv->v_type = VAR_NUMBER;
4088 		rettv->vval.v_number = val;
4089 	    }
4090 	}
4091 	else if (numeric_only)
4092 	{
4093 	    ++p;
4094 	    break;
4095 	}
4096 	else if (*p == '!')
4097 	{
4098 	    int v = tv2bool(rettv);
4099 
4100 	    // '!' is permissive in the type.
4101 	    clear_tv(rettv);
4102 	    rettv->v_type = VAR_BOOL;
4103 	    rettv->vval.v_number = v ? VVAL_FALSE : VVAL_TRUE;
4104 	}
4105     }
4106     *end = p;
4107     return OK;
4108 }
4109 
4110 /*
4111  * Recognize v: variables that are constants and set "rettv".
4112  */
4113     static void
4114 get_vim_constant(char_u **arg, typval_T *rettv)
4115 {
4116     if (STRNCMP(*arg, "v:true", 6) == 0)
4117     {
4118 	rettv->v_type = VAR_BOOL;
4119 	rettv->vval.v_number = VVAL_TRUE;
4120 	*arg += 6;
4121     }
4122     else if (STRNCMP(*arg, "v:false", 7) == 0)
4123     {
4124 	rettv->v_type = VAR_BOOL;
4125 	rettv->vval.v_number = VVAL_FALSE;
4126 	*arg += 7;
4127     }
4128     else if (STRNCMP(*arg, "v:null", 6) == 0)
4129     {
4130 	rettv->v_type = VAR_SPECIAL;
4131 	rettv->vval.v_number = VVAL_NULL;
4132 	*arg += 6;
4133     }
4134     else if (STRNCMP(*arg, "v:none", 6) == 0)
4135     {
4136 	rettv->v_type = VAR_SPECIAL;
4137 	rettv->vval.v_number = VVAL_NONE;
4138 	*arg += 6;
4139     }
4140 }
4141 
4142     exprtype_T
4143 get_compare_type(char_u *p, int *len, int *type_is)
4144 {
4145     exprtype_T	type = EXPR_UNKNOWN;
4146     int		i;
4147 
4148     switch (p[0])
4149     {
4150 	case '=':   if (p[1] == '=')
4151 			type = EXPR_EQUAL;
4152 		    else if (p[1] == '~')
4153 			type = EXPR_MATCH;
4154 		    break;
4155 	case '!':   if (p[1] == '=')
4156 			type = EXPR_NEQUAL;
4157 		    else if (p[1] == '~')
4158 			type = EXPR_NOMATCH;
4159 		    break;
4160 	case '>':   if (p[1] != '=')
4161 		    {
4162 			type = EXPR_GREATER;
4163 			*len = 1;
4164 		    }
4165 		    else
4166 			type = EXPR_GEQUAL;
4167 		    break;
4168 	case '<':   if (p[1] != '=')
4169 		    {
4170 			type = EXPR_SMALLER;
4171 			*len = 1;
4172 		    }
4173 		    else
4174 			type = EXPR_SEQUAL;
4175 		    break;
4176 	case 'i':   if (p[1] == 's')
4177 		    {
4178 			// "is" and "isnot"; but not a prefix of a name
4179 			if (p[2] == 'n' && p[3] == 'o' && p[4] == 't')
4180 			    *len = 5;
4181 			i = p[*len];
4182 			if (!isalnum(i) && i != '_')
4183 			{
4184 			    type = *len == 2 ? EXPR_IS : EXPR_ISNOT;
4185 			    *type_is = TRUE;
4186 			}
4187 		    }
4188 		    break;
4189     }
4190     return type;
4191 }
4192 
4193 /*
4194  * Skip over an expression, ignoring most errors.
4195  */
4196     static void
4197 skip_expr_cctx(char_u **arg, cctx_T *cctx)
4198 {
4199     evalarg_T	evalarg;
4200 
4201     CLEAR_FIELD(evalarg);
4202     evalarg.eval_cctx = cctx;
4203     skip_expr(arg, &evalarg);
4204 }
4205 
4206 /*
4207  * Compile code to apply '-', '+' and '!'.
4208  * When "numeric_only" is TRUE do not apply '!'.
4209  */
4210     static int
4211 compile_leader(cctx_T *cctx, int numeric_only, char_u *start, char_u **end)
4212 {
4213     char_u	*p = *end;
4214 
4215     // this works from end to start
4216     while (p > start)
4217     {
4218 	--p;
4219 	while (VIM_ISWHITE(*p))
4220 	    --p;
4221 	if (*p == '-' || *p == '+')
4222 	{
4223 	    int		negate = *p == '-';
4224 	    isn_T	*isn;
4225 	    garray_T    *stack = &cctx->ctx_type_stack;
4226 	    type_T	*type;
4227 
4228 	    type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4229 	    if (need_type(type, &t_number, -1, 0, cctx, FALSE, FALSE) == FAIL)
4230 		return FAIL;
4231 
4232 	    while (p > start && (p[-1] == '-' || p[-1] == '+'))
4233 	    {
4234 		--p;
4235 		if (*p == '-')
4236 		    negate = !negate;
4237 	    }
4238 	    // only '-' has an effect, for '+' we only check the type
4239 	    if (negate)
4240 	    {
4241 		isn = generate_instr(cctx, ISN_NEGATENR);
4242 		if (isn == NULL)
4243 		    return FAIL;
4244 	    }
4245 	}
4246 	else if (numeric_only)
4247 	{
4248 	    ++p;
4249 	    break;
4250 	}
4251 	else
4252 	{
4253 	    int  invert = *p == '!';
4254 
4255 	    while (p > start && (p[-1] == '!' || VIM_ISWHITE(p[-1])))
4256 	    {
4257 		if (p[-1] == '!')
4258 		    invert = !invert;
4259 		--p;
4260 	    }
4261 	    if (generate_2BOOL(cctx, invert, -1) == FAIL)
4262 		return FAIL;
4263 	}
4264     }
4265     *end = p;
4266     return OK;
4267 }
4268 
4269 /*
4270  * Compile "(expression)": recursive!
4271  * Return FAIL/OK.
4272  */
4273     static int
4274 compile_parenthesis(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4275 {
4276     int	    ret;
4277     char_u  *p = *arg + 1;
4278 
4279     if (may_get_next_line_error(p, arg, cctx) == FAIL)
4280 	return FAIL;
4281     if (ppconst->pp_used <= PPSIZE - 10)
4282     {
4283 	ret = compile_expr1(arg, cctx, ppconst);
4284     }
4285     else
4286     {
4287 	// Not enough space in ppconst, flush constants.
4288 	if (generate_ppconst(cctx, ppconst) == FAIL)
4289 	    return FAIL;
4290 	ret = compile_expr0(arg, cctx);
4291     }
4292     if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4293 	return FAIL;
4294     if (**arg == ')')
4295 	++*arg;
4296     else if (ret == OK)
4297     {
4298 	emsg(_(e_missing_close));
4299 	ret = FAIL;
4300     }
4301     return ret;
4302 }
4303 
4304 /*
4305  * Compile whatever comes after "name" or "name()".
4306  * Advances "*arg" only when something was recognized.
4307  */
4308     static int
4309 compile_subscript(
4310 	char_u **arg,
4311 	cctx_T *cctx,
4312 	char_u *start_leader,
4313 	char_u **end_leader,
4314 	ppconst_T *ppconst)
4315 {
4316     char_u	*name_start = *end_leader;
4317 
4318     for (;;)
4319     {
4320 	char_u *p = skipwhite(*arg);
4321 
4322 	if (*p == NUL || (VIM_ISWHITE(**arg) && vim9_comment_start(p)))
4323 	{
4324 	    char_u *next = peek_next_line_from_context(cctx);
4325 
4326 	    // If a following line starts with "->{" or "->X" advance to that
4327 	    // line, so that a line break before "->" is allowed.
4328 	    // Also if a following line starts with ".x".
4329 	    if (next != NULL &&
4330 		    ((next[0] == '-' && next[1] == '>'
4331 				 && (next[2] == '{'
4332 				       || ASCII_ISALPHA(*skipwhite(next + 2))))
4333 		    || (next[0] == '.' && eval_isdictc(next[1]))))
4334 	    {
4335 		next = next_line_from_context(cctx, TRUE);
4336 		if (next == NULL)
4337 		    return FAIL;
4338 		*arg = next;
4339 		p = skipwhite(*arg);
4340 	    }
4341 	}
4342 
4343 	// Do not skip over white space to find the "(", "execute 'x' (expr)"
4344 	// is not a function call.
4345 	if (**arg == '(')
4346 	{
4347 	    garray_T    *stack = &cctx->ctx_type_stack;
4348 	    type_T	*type;
4349 	    int		argcount = 0;
4350 
4351 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4352 		return FAIL;
4353 	    ppconst->pp_is_const = FALSE;
4354 
4355 	    // funcref(arg)
4356 	    type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4357 
4358 	    *arg = skipwhite(p + 1);
4359 	    if (compile_arguments(arg, cctx, &argcount, FALSE) == FAIL)
4360 		return FAIL;
4361 	    if (generate_PCALL(cctx, argcount, name_start, type, TRUE) == FAIL)
4362 		return FAIL;
4363 	}
4364 	else if (*p == '-' && p[1] == '>')
4365 	{
4366 	    char_u *pstart = p;
4367 
4368 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4369 		return FAIL;
4370 	    ppconst->pp_is_const = FALSE;
4371 
4372 	    // something->method()
4373 	    // Apply the '!', '-' and '+' first:
4374 	    //   -1.0->func() works like (-1.0)->func()
4375 	    if (compile_leader(cctx, TRUE, start_leader, end_leader) == FAIL)
4376 		return FAIL;
4377 
4378 	    p += 2;
4379 	    *arg = skipwhite(p);
4380 	    // No line break supported right after "->".
4381 	    if (**arg == '(')
4382 	    {
4383 		int	    argcount = 1;
4384 		garray_T    *stack = &cctx->ctx_type_stack;
4385 		int	    type_idx_start = stack->ga_len;
4386 		type_T	    *type;
4387 		int	    expr_isn_start = cctx->ctx_instr.ga_len;
4388 		int	    expr_isn_end;
4389 		int	    arg_isn_count;
4390 
4391 		// Funcref call:  list->(Refs[2])(arg)
4392 		// or lambda:	  list->((arg) => expr)(arg)
4393 		//
4394 		// Fist compile the function expression.
4395 		if (compile_parenthesis(arg, cctx, ppconst) == FAIL)
4396 		    return FAIL;
4397 
4398 		// Remember the next instruction index, where the instructions
4399 		// for arguments are being written.
4400 		expr_isn_end = cctx->ctx_instr.ga_len;
4401 
4402 		// Compile the arguments.
4403 		if (**arg != '(')
4404 		{
4405 		    if (*skipwhite(*arg) == '(')
4406 			emsg(_(e_nowhitespace));
4407 		    else
4408 			semsg(_(e_missing_paren), *arg);
4409 		    return FAIL;
4410 		}
4411 		*arg = skipwhite(*arg + 1);
4412 		if (compile_arguments(arg, cctx, &argcount, FALSE) == FAIL)
4413 		    return FAIL;
4414 
4415 		// Move the instructions for the arguments to before the
4416 		// instructions of the expression and move the type of the
4417 		// expression after the argument types.  This is what ISN_PCALL
4418 		// expects.
4419 		stack = &cctx->ctx_type_stack;
4420 		arg_isn_count = cctx->ctx_instr.ga_len - expr_isn_end;
4421 		if (arg_isn_count > 0)
4422 		{
4423 		    int	    expr_isn_count = expr_isn_end - expr_isn_start;
4424 		    isn_T   *isn = ALLOC_MULT(isn_T, expr_isn_count);
4425 
4426 		    if (isn == NULL)
4427 			return FAIL;
4428 		    mch_memmove(isn, ((isn_T *)cctx->ctx_instr.ga_data)
4429 							      + expr_isn_start,
4430 					       sizeof(isn_T) * expr_isn_count);
4431 		    mch_memmove(((isn_T *)cctx->ctx_instr.ga_data)
4432 							      + expr_isn_start,
4433 			     ((isn_T *)cctx->ctx_instr.ga_data) + expr_isn_end,
4434 						sizeof(isn_T) * arg_isn_count);
4435 		    mch_memmove(((isn_T *)cctx->ctx_instr.ga_data)
4436 					      + expr_isn_start + arg_isn_count,
4437 					  isn, sizeof(isn_T) * expr_isn_count);
4438 		    vim_free(isn);
4439 
4440 		    type = ((type_T **)stack->ga_data)[type_idx_start];
4441 		    mch_memmove(((type_T **)stack->ga_data) + type_idx_start,
4442 			      ((type_T **)stack->ga_data) + type_idx_start + 1,
4443 			      sizeof(type_T *)
4444 				       * (stack->ga_len - type_idx_start - 1));
4445 		    ((type_T **)stack->ga_data)[stack->ga_len - 1] = type;
4446 		}
4447 
4448 		type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4449 		if (generate_PCALL(cctx, argcount, p - 2, type, FALSE) == FAIL)
4450 		    return FAIL;
4451 	    }
4452 	    else
4453 	    {
4454 		// method call:  list->method()
4455 		p = *arg;
4456 		if (!eval_isnamec1(*p))
4457 		{
4458 		    semsg(_(e_trailing_arg), pstart);
4459 		    return FAIL;
4460 		}
4461 		if (ASCII_ISALPHA(*p) && p[1] == ':')
4462 		    p += 2;
4463 		for ( ; eval_isnamec(*p); ++p)
4464 		    ;
4465 		if (*p != '(')
4466 		{
4467 		    semsg(_(e_missing_paren), *arg);
4468 		    return FAIL;
4469 		}
4470 		if (compile_call(arg, p - *arg, cctx, ppconst, 1) == FAIL)
4471 		    return FAIL;
4472 	    }
4473 	}
4474 	else if (**arg == '[')
4475 	{
4476 	    int		is_slice = FALSE;
4477 
4478 	    // list index: list[123]
4479 	    // dict member: dict[key]
4480 	    // string index: text[123]
4481 	    // blob index: blob[123]
4482 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4483 		return FAIL;
4484 	    ppconst->pp_is_const = FALSE;
4485 
4486 	    ++p;
4487 	    if (may_get_next_line_error(p, arg, cctx) == FAIL)
4488 		return FAIL;
4489 	    if (**arg == ':')
4490 	    {
4491 		// missing first index is equal to zero
4492 		generate_PUSHNR(cctx, 0);
4493 	    }
4494 	    else
4495 	    {
4496 		if (compile_expr0(arg, cctx) == FAIL)
4497 		    return FAIL;
4498 		if (**arg == ':')
4499 		{
4500 		    semsg(_(e_white_space_required_before_and_after_str_at_str),
4501 								    ":", *arg);
4502 		    return FAIL;
4503 		}
4504 		if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4505 		    return FAIL;
4506 		*arg = skipwhite(*arg);
4507 	    }
4508 	    if (**arg == ':')
4509 	    {
4510 		is_slice = TRUE;
4511 		++*arg;
4512 		if (!IS_WHITE_OR_NUL(**arg) && **arg != ']')
4513 		{
4514 		    semsg(_(e_white_space_required_before_and_after_str_at_str),
4515 								    ":", *arg);
4516 		    return FAIL;
4517 		}
4518 		if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4519 		    return FAIL;
4520 		if (**arg == ']')
4521 		    // missing second index is equal to end of string
4522 		    generate_PUSHNR(cctx, -1);
4523 		else
4524 		{
4525 		    if (compile_expr0(arg, cctx) == FAIL)
4526 			return FAIL;
4527 		    if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4528 			return FAIL;
4529 		    *arg = skipwhite(*arg);
4530 		}
4531 	    }
4532 
4533 	    if (**arg != ']')
4534 	    {
4535 		emsg(_(e_missbrac));
4536 		return FAIL;
4537 	    }
4538 	    *arg = *arg + 1;
4539 
4540 	    if (compile_member(is_slice, cctx) == FAIL)
4541 		return FAIL;
4542 	}
4543 	else if (*p == '.' && p[1] != '.')
4544 	{
4545 	    // dictionary member: dict.name
4546 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4547 		return FAIL;
4548 	    ppconst->pp_is_const = FALSE;
4549 
4550 	    *arg = p + 1;
4551 	    if (IS_WHITE_OR_NUL(**arg))
4552 	    {
4553 		emsg(_(e_missing_name_after_dot));
4554 		return FAIL;
4555 	    }
4556 	    p = *arg;
4557 	    if (eval_isdictc(*p))
4558 		while (eval_isnamec(*p))
4559 		    MB_PTR_ADV(p);
4560 	    if (p == *arg)
4561 	    {
4562 		semsg(_(e_syntax_error_at_str), *arg);
4563 		return FAIL;
4564 	    }
4565 	    if (generate_STRINGMEMBER(cctx, *arg, p - *arg) == FAIL)
4566 		return FAIL;
4567 	    *arg = p;
4568 	}
4569 	else
4570 	    break;
4571     }
4572 
4573     // TODO - see handle_subscript():
4574     // Turn "dict.Func" into a partial for "Func" bound to "dict".
4575     // Don't do this when "Func" is already a partial that was bound
4576     // explicitly (pt_auto is FALSE).
4577 
4578     return OK;
4579 }
4580 
4581 /*
4582  * Compile an expression at "*arg" and add instructions to "cctx->ctx_instr".
4583  * "arg" is advanced until after the expression, skipping white space.
4584  *
4585  * If the value is a constant "ppconst->pp_used" will be non-zero.
4586  * Before instructions are generated, any values in "ppconst" will generated.
4587  *
4588  * This is the compiling equivalent of eval1(), eval2(), etc.
4589  */
4590 
4591 /*
4592  *  number		number constant
4593  *  0zFFFFFFFF		Blob constant
4594  *  "string"		string constant
4595  *  'string'		literal string constant
4596  *  &option-name	option value
4597  *  @r			register contents
4598  *  identifier		variable value
4599  *  function()		function call
4600  *  $VAR		environment variable
4601  *  (expression)	nested expression
4602  *  [expr, expr]	List
4603  *  {key: val, [key]: val}   Dictionary
4604  *
4605  *  Also handle:
4606  *  ! in front		logical NOT
4607  *  - in front		unary minus
4608  *  + in front		unary plus (ignored)
4609  *  trailing (arg)	funcref/partial call
4610  *  trailing []		subscript in String or List
4611  *  trailing .name	entry in Dictionary
4612  *  trailing ->name()	method call
4613  */
4614     static int
4615 compile_expr7(
4616 	char_u **arg,
4617 	cctx_T *cctx,
4618 	ppconst_T *ppconst)
4619 {
4620     char_u	*start_leader, *end_leader;
4621     int		ret = OK;
4622     typval_T	*rettv = &ppconst->pp_tv[ppconst->pp_used];
4623     int		used_before = ppconst->pp_used;
4624 
4625     ppconst->pp_is_const = FALSE;
4626 
4627     /*
4628      * Skip '!', '-' and '+' characters.  They are handled later.
4629      */
4630     start_leader = *arg;
4631     if (eval_leader(arg, TRUE) == FAIL)
4632 	return FAIL;
4633     end_leader = *arg;
4634 
4635     rettv->v_type = VAR_UNKNOWN;
4636     switch (**arg)
4637     {
4638 	/*
4639 	 * Number constant.
4640 	 */
4641 	case '0':	// also for blob starting with 0z
4642 	case '1':
4643 	case '2':
4644 	case '3':
4645 	case '4':
4646 	case '5':
4647 	case '6':
4648 	case '7':
4649 	case '8':
4650 	case '9':
4651 	case '.':   if (eval_number(arg, rettv, TRUE, FALSE) == FAIL)
4652 			return FAIL;
4653 		    // Apply "-" and "+" just before the number now, right to
4654 		    // left.  Matters especially when "->" follows.  Stops at
4655 		    // '!'.
4656 		    if (apply_leader(rettv, TRUE,
4657 					    start_leader, &end_leader) == FAIL)
4658 		    {
4659 			clear_tv(rettv);
4660 			return FAIL;
4661 		    }
4662 		    break;
4663 
4664 	/*
4665 	 * String constant: "string".
4666 	 */
4667 	case '"':   if (eval_string(arg, rettv, TRUE) == FAIL)
4668 			return FAIL;
4669 		    break;
4670 
4671 	/*
4672 	 * Literal string constant: 'str''ing'.
4673 	 */
4674 	case '\'':  if (eval_lit_string(arg, rettv, TRUE) == FAIL)
4675 			return FAIL;
4676 		    break;
4677 
4678 	/*
4679 	 * Constant Vim variable.
4680 	 */
4681 	case 'v':   get_vim_constant(arg, rettv);
4682 		    ret = NOTDONE;
4683 		    break;
4684 
4685 	/*
4686 	 * "true" constant
4687 	 */
4688 	case 't':   if (STRNCMP(*arg, "true", 4) == 0
4689 						   && !eval_isnamec((*arg)[4]))
4690 		    {
4691 			*arg += 4;
4692 			rettv->v_type = VAR_BOOL;
4693 			rettv->vval.v_number = VVAL_TRUE;
4694 		    }
4695 		    else
4696 			ret = NOTDONE;
4697 		    break;
4698 
4699 	/*
4700 	 * "false" constant
4701 	 */
4702 	case 'f':   if (STRNCMP(*arg, "false", 5) == 0
4703 						   && !eval_isnamec((*arg)[5]))
4704 		    {
4705 			*arg += 5;
4706 			rettv->v_type = VAR_BOOL;
4707 			rettv->vval.v_number = VVAL_FALSE;
4708 		    }
4709 		    else
4710 			ret = NOTDONE;
4711 		    break;
4712 
4713 	/*
4714 	 * "null" constant
4715 	 */
4716 	case 'n':   if (STRNCMP(*arg, "null", 4) == 0
4717 						   && !eval_isnamec((*arg)[4]))
4718 		    {
4719 			*arg += 4;
4720 			rettv->v_type = VAR_SPECIAL;
4721 			rettv->vval.v_number = VVAL_NULL;
4722 		    }
4723 		    else
4724 			ret = NOTDONE;
4725 		    break;
4726 
4727 	/*
4728 	 * List: [expr, expr]
4729 	 */
4730 	case '[':   if (generate_ppconst(cctx, ppconst) == FAIL)
4731 			return FAIL;
4732 		    ret = compile_list(arg, cctx, ppconst);
4733 		    break;
4734 
4735 	/*
4736 	 * Dictionary: {'key': val, 'key': val}
4737 	 */
4738 	case '{':   if (generate_ppconst(cctx, ppconst) == FAIL)
4739 			return FAIL;
4740 		    ret = compile_dict(arg, cctx, ppconst);
4741 		    break;
4742 
4743 	/*
4744 	 * Option value: &name
4745 	 */
4746 	case '&':	if (generate_ppconst(cctx, ppconst) == FAIL)
4747 			    return FAIL;
4748 			ret = compile_get_option(arg, cctx);
4749 			break;
4750 
4751 	/*
4752 	 * Environment variable: $VAR.
4753 	 */
4754 	case '$':	if (generate_ppconst(cctx, ppconst) == FAIL)
4755 			    return FAIL;
4756 			ret = compile_get_env(arg, cctx);
4757 			break;
4758 
4759 	/*
4760 	 * Register contents: @r.
4761 	 */
4762 	case '@':	if (generate_ppconst(cctx, ppconst) == FAIL)
4763 			    return FAIL;
4764 			ret = compile_get_register(arg, cctx);
4765 			break;
4766 	/*
4767 	 * nested expression: (expression).
4768 	 * lambda: (arg, arg) => expr
4769 	 * funcref: (arg, arg) => { statement }
4770 	 */
4771 	case '(':   // if compile_lambda returns NOTDONE then it must be (expr)
4772 		    ret = compile_lambda(arg, cctx);
4773 		    if (ret == NOTDONE)
4774 			ret = compile_parenthesis(arg, cctx, ppconst);
4775 		    break;
4776 
4777 	default:    ret = NOTDONE;
4778 		    break;
4779     }
4780     if (ret == FAIL)
4781 	return FAIL;
4782 
4783     if (rettv->v_type != VAR_UNKNOWN && used_before == ppconst->pp_used)
4784     {
4785 	if (cctx->ctx_skip == SKIP_YES)
4786 	    clear_tv(rettv);
4787 	else
4788 	    // A constant expression can possibly be handled compile time,
4789 	    // return the value instead of generating code.
4790 	    ++ppconst->pp_used;
4791     }
4792     else if (ret == NOTDONE)
4793     {
4794 	char_u	    *p;
4795 	int	    r;
4796 
4797 	if (!eval_isnamec1(**arg))
4798 	{
4799 	    if (!vim9_bad_comment(*arg))
4800 	    {
4801 		if (ends_excmd(*skipwhite(*arg)))
4802 		    semsg(_(e_empty_expression_str), *arg);
4803 		else
4804 		    semsg(_(e_name_expected_str), *arg);
4805 	    }
4806 	    return FAIL;
4807 	}
4808 
4809 	// "name" or "name()"
4810 	p = to_name_end(*arg, TRUE);
4811 	if (p - *arg == (size_t)1 && **arg == '_')
4812 	{
4813 	    emsg(_(e_cannot_use_underscore_here));
4814 	    return FAIL;
4815 	}
4816 
4817 	if (*p == '(')
4818 	{
4819 	    r = compile_call(arg, p - *arg, cctx, ppconst, 0);
4820 	}
4821 	else
4822 	{
4823 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4824 		return FAIL;
4825 	    r = compile_load(arg, p, cctx, TRUE, TRUE);
4826 	}
4827 	if (r == FAIL)
4828 	    return FAIL;
4829     }
4830 
4831     // Handle following "[]", ".member", etc.
4832     // Then deal with prefixed '-', '+' and '!', if not done already.
4833     if (compile_subscript(arg, cctx, start_leader, &end_leader,
4834 							     ppconst) == FAIL)
4835 	return FAIL;
4836     if (ppconst->pp_used > 0)
4837     {
4838 	// apply the '!', '-' and '+' before the constant
4839 	rettv = &ppconst->pp_tv[ppconst->pp_used - 1];
4840 	if (apply_leader(rettv, FALSE, start_leader, &end_leader) == FAIL)
4841 	    return FAIL;
4842 	return OK;
4843     }
4844     if (compile_leader(cctx, FALSE, start_leader, &end_leader) == FAIL)
4845 	return FAIL;
4846     return OK;
4847 }
4848 
4849 /*
4850  * Give the "white on both sides" error, taking the operator from "p[len]".
4851  */
4852     void
4853 error_white_both(char_u *op, int len)
4854 {
4855     char_u	buf[10];
4856 
4857     vim_strncpy(buf, op, len);
4858     semsg(_(e_white_space_required_before_and_after_str_at_str), buf, op);
4859 }
4860 
4861 /*
4862  * <type>expr7: runtime type check / conversion
4863  */
4864     static int
4865 compile_expr7t(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4866 {
4867     type_T *want_type = NULL;
4868 
4869     // Recognize <type>
4870     if (**arg == '<' && eval_isnamec1((*arg)[1]))
4871     {
4872 	++*arg;
4873 	want_type = parse_type(arg, cctx->ctx_type_list, TRUE);
4874 	if (want_type == NULL)
4875 	    return FAIL;
4876 
4877 	if (**arg != '>')
4878 	{
4879 	    if (*skipwhite(*arg) == '>')
4880 		semsg(_(e_no_white_space_allowed_before_str_str), ">", *arg);
4881 	    else
4882 		emsg(_(e_missing_gt));
4883 	    return FAIL;
4884 	}
4885 	++*arg;
4886 	if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4887 	    return FAIL;
4888     }
4889 
4890     if (compile_expr7(arg, cctx, ppconst) == FAIL)
4891 	return FAIL;
4892 
4893     if (want_type != NULL)
4894     {
4895 	garray_T    *stack = &cctx->ctx_type_stack;
4896 	type_T	    *actual;
4897 	where_T	    where = WHERE_INIT;
4898 
4899 	generate_ppconst(cctx, ppconst);
4900 	actual = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4901 	if (check_type(want_type, actual, FALSE, where) == FAIL)
4902 	{
4903 	    if (need_type(actual, want_type, -1, 0, cctx, FALSE, FALSE) == FAIL)
4904 		return FAIL;
4905 	}
4906     }
4907 
4908     return OK;
4909 }
4910 
4911 /*
4912  *	*	number multiplication
4913  *	/	number division
4914  *	%	number modulo
4915  */
4916     static int
4917 compile_expr6(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4918 {
4919     char_u	*op;
4920     char_u	*next;
4921     int		ppconst_used = ppconst->pp_used;
4922 
4923     // get the first expression
4924     if (compile_expr7t(arg, cctx, ppconst) == FAIL)
4925 	return FAIL;
4926 
4927     /*
4928      * Repeat computing, until no "*", "/" or "%" is following.
4929      */
4930     for (;;)
4931     {
4932 	op = may_peek_next_line(cctx, *arg, &next);
4933 	if (*op != '*' && *op != '/' && *op != '%')
4934 	    break;
4935 	if (next != NULL)
4936 	{
4937 	    *arg = next_line_from_context(cctx, TRUE);
4938 	    op = skipwhite(*arg);
4939 	}
4940 
4941 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(op[1]))
4942 	{
4943 	    error_white_both(op, 1);
4944 	    return FAIL;
4945 	}
4946 	if (may_get_next_line_error(op + 1, arg, cctx) == FAIL)
4947 	    return FAIL;
4948 
4949 	// get the second expression
4950 	if (compile_expr7t(arg, cctx, ppconst) == FAIL)
4951 	    return FAIL;
4952 
4953 	if (ppconst->pp_used == ppconst_used + 2
4954 		&& ppconst->pp_tv[ppconst_used].v_type == VAR_NUMBER
4955 		&& ppconst->pp_tv[ppconst_used + 1].v_type == VAR_NUMBER)
4956 	{
4957 	    typval_T	    *tv1 = &ppconst->pp_tv[ppconst_used];
4958 	    typval_T	    *tv2 = &ppconst->pp_tv[ppconst_used + 1];
4959 	    varnumber_T	    res = 0;
4960 	    int		    failed = FALSE;
4961 
4962 	    // both are numbers: compute the result
4963 	    switch (*op)
4964 	    {
4965 		case '*': res = tv1->vval.v_number * tv2->vval.v_number;
4966 			  break;
4967 		case '/': res = num_divide(tv1->vval.v_number,
4968 						  tv2->vval.v_number, &failed);
4969 			  break;
4970 		case '%': res = num_modulus(tv1->vval.v_number,
4971 						  tv2->vval.v_number, &failed);
4972 			  break;
4973 	    }
4974 	    if (failed)
4975 		return FAIL;
4976 	    tv1->vval.v_number = res;
4977 	    --ppconst->pp_used;
4978 	}
4979 	else
4980 	{
4981 	    generate_ppconst(cctx, ppconst);
4982 	    generate_two_op(cctx, op);
4983 	}
4984     }
4985 
4986     return OK;
4987 }
4988 
4989 /*
4990  *      +	number addition or list/blobl concatenation
4991  *      -	number subtraction
4992  *      ..	string concatenation
4993  */
4994     static int
4995 compile_expr5(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4996 {
4997     char_u	*op;
4998     char_u	*next;
4999     int		oplen;
5000     int		ppconst_used = ppconst->pp_used;
5001 
5002     // get the first variable
5003     if (compile_expr6(arg, cctx, ppconst) == FAIL)
5004 	return FAIL;
5005 
5006     /*
5007      * Repeat computing, until no "+", "-" or ".." is following.
5008      */
5009     for (;;)
5010     {
5011 	op = may_peek_next_line(cctx, *arg, &next);
5012 	if (*op != '+' && *op != '-' && !(*op == '.' && *(op + 1) == '.'))
5013 	    break;
5014 	if (op[0] == op[1] && *op != '.' && next)
5015 	    // Finding "++" or "--" on the next line is a separate command.
5016 	    // But ".." is concatenation.
5017 	    break;
5018 	oplen = (*op == '.' ? 2 : 1);
5019 	if (next != NULL)
5020 	{
5021 	    *arg = next_line_from_context(cctx, TRUE);
5022 	    op = skipwhite(*arg);
5023 	}
5024 
5025 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(op[oplen]))
5026 	{
5027 	    error_white_both(op, oplen);
5028 	    return FAIL;
5029 	}
5030 
5031 	if (may_get_next_line_error(op + oplen, arg, cctx) == FAIL)
5032 	    return FAIL;
5033 
5034 	// get the second expression
5035 	if (compile_expr6(arg, cctx, ppconst) == FAIL)
5036 	    return FAIL;
5037 
5038 	if (ppconst->pp_used == ppconst_used + 2
5039 		&& (*op == '.'
5040 		    ? (ppconst->pp_tv[ppconst_used].v_type == VAR_STRING
5041 		    && ppconst->pp_tv[ppconst_used + 1].v_type == VAR_STRING)
5042 		    : (ppconst->pp_tv[ppconst_used].v_type == VAR_NUMBER
5043 		    && ppconst->pp_tv[ppconst_used + 1].v_type == VAR_NUMBER)))
5044 	{
5045 	    typval_T *tv1 = &ppconst->pp_tv[ppconst_used];
5046 	    typval_T *tv2 = &ppconst->pp_tv[ppconst_used + 1];
5047 
5048 	    // concat/subtract/add constant numbers
5049 	    if (*op == '+')
5050 		tv1->vval.v_number = tv1->vval.v_number + tv2->vval.v_number;
5051 	    else if (*op == '-')
5052 		tv1->vval.v_number = tv1->vval.v_number - tv2->vval.v_number;
5053 	    else
5054 	    {
5055 		// concatenate constant strings
5056 		char_u *s1 = tv1->vval.v_string;
5057 		char_u *s2 = tv2->vval.v_string;
5058 		size_t len1 = STRLEN(s1);
5059 
5060 		tv1->vval.v_string = alloc((int)(len1 + STRLEN(s2) + 1));
5061 		if (tv1->vval.v_string == NULL)
5062 		{
5063 		    clear_ppconst(ppconst);
5064 		    return FAIL;
5065 		}
5066 		mch_memmove(tv1->vval.v_string, s1, len1);
5067 		STRCPY(tv1->vval.v_string + len1, s2);
5068 		vim_free(s1);
5069 		vim_free(s2);
5070 	    }
5071 	    --ppconst->pp_used;
5072 	}
5073 	else
5074 	{
5075 	    generate_ppconst(cctx, ppconst);
5076 	    ppconst->pp_is_const = FALSE;
5077 	    if (*op == '.')
5078 	    {
5079 		if (may_generate_2STRING(-2, FALSE, cctx) == FAIL
5080 			|| may_generate_2STRING(-1, FALSE, cctx) == FAIL)
5081 		    return FAIL;
5082 		generate_instr_drop(cctx, ISN_CONCAT, 1);
5083 	    }
5084 	    else
5085 		generate_two_op(cctx, op);
5086 	}
5087     }
5088 
5089     return OK;
5090 }
5091 
5092 /*
5093  * expr5a == expr5b
5094  * expr5a =~ expr5b
5095  * expr5a != expr5b
5096  * expr5a !~ expr5b
5097  * expr5a > expr5b
5098  * expr5a >= expr5b
5099  * expr5a < expr5b
5100  * expr5a <= expr5b
5101  * expr5a is expr5b
5102  * expr5a isnot expr5b
5103  *
5104  * Produces instructions:
5105  *	EVAL expr5a		Push result of "expr5a"
5106  *	EVAL expr5b		Push result of "expr5b"
5107  *	COMPARE			one of the compare instructions
5108  */
5109     static int
5110 compile_expr4(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
5111 {
5112     exprtype_T	type = EXPR_UNKNOWN;
5113     char_u	*p;
5114     char_u	*next;
5115     int		len = 2;
5116     int		type_is = FALSE;
5117     int		ppconst_used = ppconst->pp_used;
5118 
5119     // get the first variable
5120     if (compile_expr5(arg, cctx, ppconst) == FAIL)
5121 	return FAIL;
5122 
5123     p = may_peek_next_line(cctx, *arg, &next);
5124     type = get_compare_type(p, &len, &type_is);
5125 
5126     /*
5127      * If there is a comparative operator, use it.
5128      */
5129     if (type != EXPR_UNKNOWN)
5130     {
5131 	int ic = FALSE;  // Default: do not ignore case
5132 
5133 	if (next != NULL)
5134 	{
5135 	    *arg = next_line_from_context(cctx, TRUE);
5136 	    p = skipwhite(*arg);
5137 	}
5138 	if (type_is && (p[len] == '?' || p[len] == '#'))
5139 	{
5140 	    semsg(_(e_invalid_expression_str), *arg);
5141 	    return FAIL;
5142 	}
5143 	// extra question mark appended: ignore case
5144 	if (p[len] == '?')
5145 	{
5146 	    ic = TRUE;
5147 	    ++len;
5148 	}
5149 	// extra '#' appended: match case (ignored)
5150 	else if (p[len] == '#')
5151 	    ++len;
5152 	// nothing appended: match case
5153 
5154 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[len]))
5155 	{
5156 	    error_white_both(p, len);
5157 	    return FAIL;
5158 	}
5159 
5160 	// get the second variable
5161 	if (may_get_next_line_error(p + len, arg, cctx) == FAIL)
5162 	    return FAIL;
5163 
5164 	if (compile_expr5(arg, cctx, ppconst) == FAIL)
5165 	    return FAIL;
5166 
5167 	if (ppconst->pp_used == ppconst_used + 2)
5168 	{
5169 	    typval_T *	tv1 = &ppconst->pp_tv[ppconst->pp_used - 2];
5170 	    typval_T	*tv2 = &ppconst->pp_tv[ppconst->pp_used - 1];
5171 	    int		ret;
5172 
5173 	    // Both sides are a constant, compute the result now.
5174 	    // First check for a valid combination of types, this is more
5175 	    // strict than typval_compare().
5176 	    if (check_compare_types(type, tv1, tv2) == FAIL)
5177 		ret = FAIL;
5178 	    else
5179 	    {
5180 		ret = typval_compare(tv1, tv2, type, ic);
5181 		tv1->v_type = VAR_BOOL;
5182 		tv1->vval.v_number = tv1->vval.v_number
5183 						      ? VVAL_TRUE : VVAL_FALSE;
5184 		clear_tv(tv2);
5185 		--ppconst->pp_used;
5186 	    }
5187 	    return ret;
5188 	}
5189 
5190 	generate_ppconst(cctx, ppconst);
5191 	return generate_COMPARE(cctx, type, ic);
5192     }
5193 
5194     return OK;
5195 }
5196 
5197 static int compile_expr3(char_u **arg,  cctx_T *cctx, ppconst_T *ppconst);
5198 
5199 /*
5200  * Compile || or &&.
5201  */
5202     static int
5203 compile_and_or(
5204 	char_u **arg,
5205 	cctx_T	*cctx,
5206 	char	*op,
5207 	ppconst_T *ppconst,
5208 	int	ppconst_used UNUSED)
5209 {
5210     char_u	*next;
5211     char_u	*p = may_peek_next_line(cctx, *arg, &next);
5212     int		opchar = *op;
5213 
5214     if (p[0] == opchar && p[1] == opchar)
5215     {
5216 	garray_T	*instr = &cctx->ctx_instr;
5217 	garray_T	end_ga;
5218 
5219 	/*
5220 	 * Repeat until there is no following "||" or "&&"
5221 	 */
5222 	ga_init2(&end_ga, sizeof(int), 10);
5223 	while (p[0] == opchar && p[1] == opchar)
5224 	{
5225 	    long	start_lnum = SOURCING_LNUM;
5226 	    long	save_sourcing_lnum;
5227 	    int		start_ctx_lnum = cctx->ctx_lnum;
5228 	    int		save_lnum;
5229 	    int		status;
5230 
5231 	    if (next != NULL)
5232 	    {
5233 		*arg = next_line_from_context(cctx, TRUE);
5234 		p = skipwhite(*arg);
5235 	    }
5236 
5237 	    if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[2]))
5238 	    {
5239 		semsg(_(e_white_space_required_before_and_after_str_at_str),
5240 									op, p);
5241 		return FAIL;
5242 	    }
5243 
5244 	    save_sourcing_lnum = SOURCING_LNUM;
5245 	    SOURCING_LNUM = start_lnum;
5246 	    save_lnum = cctx->ctx_lnum;
5247 	    cctx->ctx_lnum = start_ctx_lnum;
5248 
5249 	    status = check_ppconst_bool(ppconst);
5250 	    if (status != FAIL)
5251 	    {
5252 		// TODO: use ppconst if the value is a constant
5253 		generate_ppconst(cctx, ppconst);
5254 
5255 		// Every part must evaluate to a bool.
5256 		status = bool_on_stack(cctx);
5257 		if (status != FAIL)
5258 		    status = ga_grow(&end_ga, 1);
5259 	    }
5260 	    cctx->ctx_lnum = save_lnum;
5261 	    if (status == FAIL)
5262 	    {
5263 		ga_clear(&end_ga);
5264 		return FAIL;
5265 	    }
5266 
5267 	    *(((int *)end_ga.ga_data) + end_ga.ga_len) = instr->ga_len;
5268 	    ++end_ga.ga_len;
5269 	    generate_JUMP(cctx, opchar == '|'
5270 				 ?  JUMP_IF_COND_TRUE : JUMP_IF_COND_FALSE, 0);
5271 
5272 	    // eval the next expression
5273 	    SOURCING_LNUM = save_sourcing_lnum;
5274 	    if (may_get_next_line_error(p + 2, arg, cctx) == FAIL)
5275 	    {
5276 		ga_clear(&end_ga);
5277 		return FAIL;
5278 	    }
5279 
5280 	    if ((opchar == '|' ? compile_expr3(arg, cctx, ppconst)
5281 				  : compile_expr4(arg, cctx, ppconst)) == FAIL)
5282 	    {
5283 		ga_clear(&end_ga);
5284 		return FAIL;
5285 	    }
5286 
5287 	    p = may_peek_next_line(cctx, *arg, &next);
5288 	}
5289 
5290 	if (check_ppconst_bool(ppconst) == FAIL)
5291 	{
5292 	    ga_clear(&end_ga);
5293 	    return FAIL;
5294 	}
5295 	generate_ppconst(cctx, ppconst);
5296 
5297 	// Every part must evaluate to a bool.
5298 	if (bool_on_stack(cctx) == FAIL)
5299 	{
5300 	    ga_clear(&end_ga);
5301 	    return FAIL;
5302 	}
5303 
5304 	// Fill in the end label in all jumps.
5305 	while (end_ga.ga_len > 0)
5306 	{
5307 	    isn_T	*isn;
5308 
5309 	    --end_ga.ga_len;
5310 	    isn = ((isn_T *)instr->ga_data)
5311 				  + *(((int *)end_ga.ga_data) + end_ga.ga_len);
5312 	    isn->isn_arg.jump.jump_where = instr->ga_len;
5313 	}
5314 	ga_clear(&end_ga);
5315     }
5316 
5317     return OK;
5318 }
5319 
5320 /*
5321  * expr4a && expr4a && expr4a	    logical AND
5322  *
5323  * Produces instructions:
5324  *	EVAL expr4a		Push result of "expr4a"
5325  *	COND2BOOL		convert to bool if needed
5326  *	JUMP_IF_COND_FALSE end
5327  *	EVAL expr4b		Push result of "expr4b"
5328  *	JUMP_IF_COND_FALSE end
5329  *	EVAL expr4c		Push result of "expr4c"
5330  * end:
5331  */
5332     static int
5333 compile_expr3(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
5334 {
5335     int		ppconst_used = ppconst->pp_used;
5336 
5337     // get the first variable
5338     if (compile_expr4(arg, cctx, ppconst) == FAIL)
5339 	return FAIL;
5340 
5341     // || and && work almost the same
5342     return compile_and_or(arg, cctx, "&&", ppconst, ppconst_used);
5343 }
5344 
5345 /*
5346  * expr3a || expr3b || expr3c	    logical OR
5347  *
5348  * Produces instructions:
5349  *	EVAL expr3a		Push result of "expr3a"
5350  *	COND2BOOL		convert to bool if needed
5351  *	JUMP_IF_COND_TRUE end
5352  *	EVAL expr3b		Push result of "expr3b"
5353  *	JUMP_IF_COND_TRUE end
5354  *	EVAL expr3c		Push result of "expr3c"
5355  * end:
5356  */
5357     static int
5358 compile_expr2(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
5359 {
5360     int		ppconst_used = ppconst->pp_used;
5361 
5362     // eval the first expression
5363     if (compile_expr3(arg, cctx, ppconst) == FAIL)
5364 	return FAIL;
5365 
5366     // || and && work almost the same
5367     return compile_and_or(arg, cctx, "||", ppconst, ppconst_used);
5368 }
5369 
5370 /*
5371  * Toplevel expression: expr2 ? expr1a : expr1b
5372  * Produces instructions:
5373  *	EVAL expr2		Push result of "expr2"
5374  *      JUMP_IF_FALSE alt	jump if false
5375  *      EVAL expr1a
5376  *      JUMP_ALWAYS end
5377  * alt:	EVAL expr1b
5378  * end:
5379  *
5380  * Toplevel expression: expr2 ?? expr1
5381  * Produces instructions:
5382  *	EVAL expr2		    Push result of "expr2"
5383  *      JUMP_AND_KEEP_IF_TRUE end   jump if true
5384  *      EVAL expr1
5385  * end:
5386  */
5387     static int
5388 compile_expr1(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
5389 {
5390     char_u	*p;
5391     int		ppconst_used = ppconst->pp_used;
5392     char_u	*next;
5393 
5394     // Ignore all kinds of errors when not producing code.
5395     if (cctx->ctx_skip == SKIP_YES)
5396     {
5397 	skip_expr_cctx(arg, cctx);
5398 	return OK;
5399     }
5400 
5401     // Evaluate the first expression.
5402     if (compile_expr2(arg, cctx, ppconst) == FAIL)
5403 	return FAIL;
5404 
5405     p = may_peek_next_line(cctx, *arg, &next);
5406     if (*p == '?')
5407     {
5408 	int		op_falsy = p[1] == '?';
5409 	garray_T	*instr = &cctx->ctx_instr;
5410 	garray_T	*stack = &cctx->ctx_type_stack;
5411 	int		alt_idx = instr->ga_len;
5412 	int		end_idx = 0;
5413 	isn_T		*isn;
5414 	type_T		*type1 = NULL;
5415 	int		has_const_expr = FALSE;
5416 	int		const_value = FALSE;
5417 	int		save_skip = cctx->ctx_skip;
5418 
5419 	if (next != NULL)
5420 	{
5421 	    *arg = next_line_from_context(cctx, TRUE);
5422 	    p = skipwhite(*arg);
5423 	}
5424 
5425 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[1 + op_falsy]))
5426 	{
5427 	    semsg(_(e_white_space_required_before_and_after_str_at_str),
5428 						     op_falsy ? "??" : "?", p);
5429 	    return FAIL;
5430 	}
5431 
5432 	if (ppconst->pp_used == ppconst_used + 1)
5433 	{
5434 	    // the condition is a constant, we know whether the ? or the :
5435 	    // expression is to be evaluated.
5436 	    has_const_expr = TRUE;
5437 	    if (op_falsy)
5438 		const_value = tv2bool(&ppconst->pp_tv[ppconst_used]);
5439 	    else
5440 	    {
5441 		int error = FALSE;
5442 
5443 		const_value = tv_get_bool_chk(&ppconst->pp_tv[ppconst_used],
5444 								       &error);
5445 		if (error)
5446 		    return FAIL;
5447 	    }
5448 	    cctx->ctx_skip = save_skip == SKIP_YES ||
5449 		 (op_falsy ? const_value : !const_value) ? SKIP_YES : SKIP_NOT;
5450 
5451 	    if (op_falsy && cctx->ctx_skip == SKIP_YES)
5452 		// "left ?? right" and "left" is truthy: produce "left"
5453 		generate_ppconst(cctx, ppconst);
5454 	    else
5455 	    {
5456 		clear_tv(&ppconst->pp_tv[ppconst_used]);
5457 		--ppconst->pp_used;
5458 	    }
5459 	}
5460 	else
5461 	{
5462 	    generate_ppconst(cctx, ppconst);
5463 	    if (op_falsy)
5464 		end_idx = instr->ga_len;
5465 	    generate_JUMP(cctx, op_falsy
5466 				   ? JUMP_AND_KEEP_IF_TRUE : JUMP_IF_FALSE, 0);
5467 	    if (op_falsy)
5468 		type1 = ((type_T **)stack->ga_data)[stack->ga_len];
5469 	}
5470 
5471 	// evaluate the second expression; any type is accepted
5472 	if (may_get_next_line_error(p + 1 + op_falsy, arg, cctx) == FAIL)
5473 	    return FAIL;
5474 	if (compile_expr1(arg, cctx, ppconst) == FAIL)
5475 	    return FAIL;
5476 
5477 	if (!has_const_expr)
5478 	{
5479 	    generate_ppconst(cctx, ppconst);
5480 
5481 	    if (!op_falsy)
5482 	    {
5483 		// remember the type and drop it
5484 		--stack->ga_len;
5485 		type1 = ((type_T **)stack->ga_data)[stack->ga_len];
5486 
5487 		end_idx = instr->ga_len;
5488 		generate_JUMP(cctx, JUMP_ALWAYS, 0);
5489 
5490 		// jump here from JUMP_IF_FALSE
5491 		isn = ((isn_T *)instr->ga_data) + alt_idx;
5492 		isn->isn_arg.jump.jump_where = instr->ga_len;
5493 	    }
5494 	}
5495 
5496 	if (!op_falsy)
5497 	{
5498 	    // Check for the ":".
5499 	    p = may_peek_next_line(cctx, *arg, &next);
5500 	    if (*p != ':')
5501 	    {
5502 		emsg(_(e_missing_colon));
5503 		return FAIL;
5504 	    }
5505 	    if (next != NULL)
5506 	    {
5507 		*arg = next_line_from_context(cctx, TRUE);
5508 		p = skipwhite(*arg);
5509 	    }
5510 
5511 	    if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[1]))
5512 	    {
5513 		semsg(_(e_white_space_required_before_and_after_str_at_str),
5514 								       ":", p);
5515 		return FAIL;
5516 	    }
5517 
5518 	    // evaluate the third expression
5519 	    if (has_const_expr)
5520 		cctx->ctx_skip = save_skip == SKIP_YES || const_value
5521 							 ? SKIP_YES : SKIP_NOT;
5522 	    if (may_get_next_line_error(p + 1, arg, cctx) == FAIL)
5523 		return FAIL;
5524 	    if (compile_expr1(arg, cctx, ppconst) == FAIL)
5525 		return FAIL;
5526 	}
5527 
5528 	if (!has_const_expr)
5529 	{
5530 	    type_T	**typep;
5531 
5532 	    generate_ppconst(cctx, ppconst);
5533 
5534 	    // If the types differ, the result has a more generic type.
5535 	    typep = ((type_T **)stack->ga_data) + stack->ga_len - 1;
5536 	    common_type(type1, *typep, typep, cctx->ctx_type_list);
5537 
5538 	    // jump here from JUMP_ALWAYS or JUMP_AND_KEEP_IF_TRUE
5539 	    isn = ((isn_T *)instr->ga_data) + end_idx;
5540 	    isn->isn_arg.jump.jump_where = instr->ga_len;
5541 	}
5542 
5543 	cctx->ctx_skip = save_skip;
5544     }
5545     return OK;
5546 }
5547 
5548 /*
5549  * Toplevel expression.
5550  * Sets "is_const" (if not NULL) to indicate the value is a constant.
5551  * Returns OK or FAIL.
5552  */
5553     static int
5554 compile_expr0_ext(char_u **arg,  cctx_T *cctx, int *is_const)
5555 {
5556     ppconst_T	ppconst;
5557 
5558     CLEAR_FIELD(ppconst);
5559     if (compile_expr1(arg, cctx, &ppconst) == FAIL)
5560     {
5561 	clear_ppconst(&ppconst);
5562 	return FAIL;
5563     }
5564     if (is_const != NULL)
5565 	*is_const = ppconst.pp_used > 0 || ppconst.pp_is_const;
5566     if (generate_ppconst(cctx, &ppconst) == FAIL)
5567 	return FAIL;
5568     return OK;
5569 }
5570 
5571 /*
5572  * Toplevel expression.
5573  */
5574     static int
5575 compile_expr0(char_u **arg,  cctx_T *cctx)
5576 {
5577     return compile_expr0_ext(arg, cctx, NULL);
5578 }
5579 
5580 /*
5581  * Compile "return [expr]".
5582  * When "legacy" is TRUE evaluate [expr] with legacy syntax
5583  */
5584     static char_u *
5585 compile_return(char_u *arg, int check_return_type, int legacy, cctx_T *cctx)
5586 {
5587     char_u	*p = arg;
5588     garray_T	*stack = &cctx->ctx_type_stack;
5589     type_T	*stack_type;
5590 
5591     if (*p != NUL && *p != '|' && *p != '\n')
5592     {
5593 	if (legacy)
5594 	{
5595 	    int save_flags = cmdmod.cmod_flags;
5596 
5597 	    generate_LEGACY_EVAL(cctx, p);
5598 	    if (need_type(&t_any, cctx->ctx_ufunc->uf_ret_type, -1,
5599 						0, cctx, FALSE, FALSE) == FAIL)
5600 		return NULL;
5601 	    cmdmod.cmod_flags |= CMOD_LEGACY;
5602 	    (void)skip_expr(&p, NULL);
5603 	    cmdmod.cmod_flags = save_flags;
5604 	}
5605 	else
5606 	{
5607 	    // compile return argument into instructions
5608 	    if (compile_expr0(&p, cctx) == FAIL)
5609 		return NULL;
5610 	}
5611 
5612 	if (cctx->ctx_skip != SKIP_YES)
5613 	{
5614 	    // "check_return_type" with uf_ret_type set to &t_unknown is used
5615 	    // for an inline function without a specified return type.  Set the
5616 	    // return type here.
5617 	    stack_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
5618 	    if ((check_return_type && (cctx->ctx_ufunc->uf_ret_type == NULL
5619 				|| cctx->ctx_ufunc->uf_ret_type == &t_unknown
5620 				|| cctx->ctx_ufunc->uf_ret_type == &t_any))
5621 		    || (!check_return_type
5622 				&& cctx->ctx_ufunc->uf_ret_type == &t_unknown))
5623 	    {
5624 		cctx->ctx_ufunc->uf_ret_type = stack_type;
5625 	    }
5626 	    else
5627 	    {
5628 		if (cctx->ctx_ufunc->uf_ret_type->tt_type == VAR_VOID
5629 			&& stack_type->tt_type != VAR_VOID
5630 			&& stack_type->tt_type != VAR_UNKNOWN)
5631 		{
5632 		    emsg(_(e_returning_value_in_function_without_return_type));
5633 		    return NULL;
5634 		}
5635 		if (need_type(stack_type, cctx->ctx_ufunc->uf_ret_type, -1,
5636 						0, cctx, FALSE, FALSE) == FAIL)
5637 		    return NULL;
5638 	    }
5639 	}
5640     }
5641     else
5642     {
5643 	// "check_return_type" cannot be TRUE, only used for a lambda which
5644 	// always has an argument.
5645 	if (cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_VOID
5646 		&& cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_UNKNOWN)
5647 	{
5648 	    emsg(_(e_missing_return_value));
5649 	    return NULL;
5650 	}
5651 
5652 	// No argument, return zero.
5653 	generate_PUSHNR(cctx, 0);
5654     }
5655 
5656     // Undo any command modifiers.
5657     generate_undo_cmdmods(cctx);
5658 
5659     if (cctx->ctx_skip != SKIP_YES && generate_instr(cctx, ISN_RETURN) == NULL)
5660 	return NULL;
5661 
5662     // "return val | endif" is possible
5663     return skipwhite(p);
5664 }
5665 
5666 /*
5667  * Get a line from the compilation context, compatible with exarg_T getline().
5668  * Return a pointer to the line in allocated memory.
5669  * Return NULL for end-of-file or some error.
5670  */
5671     static char_u *
5672 exarg_getline(
5673 	int c UNUSED,
5674 	void *cookie,
5675 	int indent UNUSED,
5676 	getline_opt_T options UNUSED)
5677 {
5678     cctx_T  *cctx = (cctx_T *)cookie;
5679     char_u  *p;
5680 
5681     for (;;)
5682     {
5683 	if (cctx->ctx_lnum >= cctx->ctx_ufunc->uf_lines.ga_len - 1)
5684 	    return NULL;
5685 	++cctx->ctx_lnum;
5686 	p = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum];
5687 	// Comment lines result in NULL pointers, skip them.
5688 	if (p != NULL)
5689 	    return vim_strsave(p);
5690     }
5691 }
5692 
5693     void
5694 fill_exarg_from_cctx(exarg_T *eap, cctx_T *cctx)
5695 {
5696     eap->getline = exarg_getline;
5697     eap->cookie = cctx;
5698 }
5699 
5700 /*
5701  * Compile a nested :def command.
5702  */
5703     static char_u *
5704 compile_nested_function(exarg_T *eap, cctx_T *cctx)
5705 {
5706     int		is_global = *eap->arg == 'g' && eap->arg[1] == ':';
5707     char_u	*name_start = eap->arg;
5708     char_u	*name_end = to_name_end(eap->arg, TRUE);
5709     char_u	*lambda_name;
5710     ufunc_T	*ufunc;
5711     int		r = FAIL;
5712     compiletype_T   compile_type;
5713 
5714     if (eap->forceit)
5715     {
5716 	emsg(_(e_cannot_use_bang_with_nested_def));
5717 	return NULL;
5718     }
5719 
5720     if (*name_start == '/')
5721     {
5722 	name_end = skip_regexp(name_start + 1, '/', TRUE);
5723 	if (*name_end == '/')
5724 	    ++name_end;
5725 	set_nextcmd(eap, name_end);
5726     }
5727     if (name_end == name_start || *skipwhite(name_end) != '(')
5728     {
5729 	if (!ends_excmd2(name_start, name_end))
5730 	{
5731 	    semsg(_(e_invalid_command_str), eap->cmd);
5732 	    return NULL;
5733 	}
5734 
5735 	// "def" or "def Name": list functions
5736 	if (generate_DEF(cctx, name_start, name_end - name_start) == FAIL)
5737 	    return NULL;
5738 	return eap->nextcmd == NULL ? (char_u *)"" : eap->nextcmd;
5739     }
5740 
5741     // Only g:Func() can use a namespace.
5742     if (name_start[1] == ':' && !is_global)
5743     {
5744 	semsg(_(e_namespace_not_supported_str), name_start);
5745 	return NULL;
5746     }
5747     if (check_defined(name_start, name_end - name_start, cctx, FALSE) == FAIL)
5748 	return NULL;
5749 
5750     eap->arg = name_end;
5751     fill_exarg_from_cctx(eap, cctx);
5752 
5753     eap->forceit = FALSE;
5754     lambda_name = vim_strsave(get_lambda_name());
5755     if (lambda_name == NULL)
5756 	return NULL;
5757     ufunc = define_function(eap, lambda_name);
5758 
5759     if (ufunc == NULL)
5760     {
5761 	r = eap->skip ? OK : FAIL;
5762 	goto theend;
5763     }
5764 
5765     // copy over the block scope IDs before compiling
5766     if (!is_global && cctx->ctx_ufunc->uf_block_depth > 0)
5767     {
5768 	int block_depth = cctx->ctx_ufunc->uf_block_depth;
5769 
5770 	ufunc->uf_block_ids = ALLOC_MULT(int, block_depth);
5771 	if (ufunc->uf_block_ids != NULL)
5772 	{
5773 	    mch_memmove(ufunc->uf_block_ids, cctx->ctx_ufunc->uf_block_ids,
5774 						    sizeof(int) * block_depth);
5775 	    ufunc->uf_block_depth = block_depth;
5776 	}
5777     }
5778 
5779     compile_type = COMPILE_TYPE(ufunc);
5780 #ifdef FEAT_PROFILE
5781     // If the outer function is profiled, also compile the nested function for
5782     // profiling.
5783     if (cctx->ctx_compile_type == CT_PROFILE)
5784 	compile_type = CT_PROFILE;
5785 #endif
5786     if (func_needs_compiling(ufunc, compile_type)
5787 	    && compile_def_function(ufunc, TRUE, compile_type, cctx) == FAIL)
5788     {
5789 	func_ptr_unref(ufunc);
5790 	goto theend;
5791     }
5792 
5793 #ifdef FEAT_PROFILE
5794     // When the outer function is compiled for profiling, the nested function
5795     // may be called without profiling.  Compile it here in the right context.
5796     if (compile_type == CT_PROFILE && func_needs_compiling(ufunc, CT_NONE))
5797 	compile_def_function(ufunc, FALSE, CT_NONE, cctx);
5798 #endif
5799 
5800     if (is_global)
5801     {
5802 	char_u *func_name = vim_strnsave(name_start + 2,
5803 						    name_end - name_start - 2);
5804 
5805 	if (func_name == NULL)
5806 	    r = FAIL;
5807 	else
5808 	{
5809 	    r = generate_NEWFUNC(cctx, lambda_name, func_name);
5810 	    lambda_name = NULL;
5811 	}
5812     }
5813     else
5814     {
5815 	// Define a local variable for the function reference.
5816 	lvar_T	*lvar = reserve_local(cctx, name_start, name_end - name_start,
5817 						    TRUE, ufunc->uf_func_type);
5818 
5819 	if (lvar == NULL)
5820 	    goto theend;
5821 	if (generate_FUNCREF(cctx, ufunc) == FAIL)
5822 	    goto theend;
5823 	r = generate_STORE(cctx, ISN_STORE, lvar->lv_idx, NULL);
5824     }
5825 
5826 theend:
5827     vim_free(lambda_name);
5828     return r == FAIL ? NULL : (char_u *)"";
5829 }
5830 
5831 /*
5832  * Return the length of an assignment operator, or zero if there isn't one.
5833  */
5834     int
5835 assignment_len(char_u *p, int *heredoc)
5836 {
5837     if (*p == '=')
5838     {
5839 	if (p[1] == '<' && p[2] == '<')
5840 	{
5841 	    *heredoc = TRUE;
5842 	    return 3;
5843 	}
5844 	return 1;
5845     }
5846     if (vim_strchr((char_u *)"+-*/%", *p) != NULL && p[1] == '=')
5847 	return 2;
5848     if (STRNCMP(p, "..=", 3) == 0)
5849 	return 3;
5850     return 0;
5851 }
5852 
5853 /*
5854  * Generate the load instruction for "name".
5855  */
5856     static void
5857 generate_loadvar(
5858 	cctx_T		*cctx,
5859 	assign_dest_T	dest,
5860 	char_u		*name,
5861 	lvar_T		*lvar,
5862 	type_T		*type)
5863 {
5864     switch (dest)
5865     {
5866 	case dest_option:
5867 	    generate_LOAD(cctx, ISN_LOADOPT, 0, name, type);
5868 	    break;
5869 	case dest_global:
5870 	    if (vim_strchr(name, AUTOLOAD_CHAR) == NULL)
5871 		generate_LOAD(cctx, ISN_LOADG, 0, name + 2, type);
5872 	    else
5873 		generate_LOAD(cctx, ISN_LOADAUTO, 0, name, type);
5874 	    break;
5875 	case dest_buffer:
5876 	    generate_LOAD(cctx, ISN_LOADB, 0, name + 2, type);
5877 	    break;
5878 	case dest_window:
5879 	    generate_LOAD(cctx, ISN_LOADW, 0, name + 2, type);
5880 	    break;
5881 	case dest_tab:
5882 	    generate_LOAD(cctx, ISN_LOADT, 0, name + 2, type);
5883 	    break;
5884 	case dest_script:
5885 	    compile_load_scriptvar(cctx,
5886 		    name + (name[1] == ':' ? 2 : 0), NULL, NULL, TRUE);
5887 	    break;
5888 	case dest_env:
5889 	    // Include $ in the name here
5890 	    generate_LOAD(cctx, ISN_LOADENV, 0, name, type);
5891 	    break;
5892 	case dest_reg:
5893 	    generate_LOAD(cctx, ISN_LOADREG, name[1], NULL, &t_string);
5894 	    break;
5895 	case dest_vimvar:
5896 	    generate_LOADV(cctx, name + 2, TRUE);
5897 	    break;
5898 	case dest_local:
5899 	    if (lvar->lv_from_outer > 0)
5900 		generate_LOADOUTER(cctx, lvar->lv_idx, lvar->lv_from_outer,
5901 									 type);
5902 	    else
5903 		generate_LOAD(cctx, ISN_LOAD, lvar->lv_idx, NULL, type);
5904 	    break;
5905 	case dest_expr:
5906 	    // list or dict value should already be on the stack.
5907 	    break;
5908     }
5909 }
5910 
5911 /*
5912  * Skip over "[expr]" or ".member".
5913  * Does not check for any errors.
5914  */
5915     static char_u *
5916 skip_index(char_u *start)
5917 {
5918     char_u *p = start;
5919 
5920     if (*p == '[')
5921     {
5922 	p = skipwhite(p + 1);
5923 	(void)skip_expr(&p, NULL);
5924 	p = skipwhite(p);
5925 	if (*p == ']')
5926 	    return p + 1;
5927 	return p;
5928     }
5929     // if (*p == '.')
5930     return to_name_end(p + 1, TRUE);
5931 }
5932 
5933     void
5934 vim9_declare_error(char_u *name)
5935 {
5936     char *scope = "";
5937 
5938     switch (*name)
5939     {
5940 	case 'g': scope = _("global"); break;
5941 	case 'b': scope = _("buffer"); break;
5942 	case 'w': scope = _("window"); break;
5943 	case 't': scope = _("tab"); break;
5944 	case 'v': scope = "v:"; break;
5945 	case '$': semsg(_(e_cannot_declare_an_environment_variable), name);
5946 		  return;
5947 	case '&': semsg(_(e_cannot_declare_an_option), name);
5948 		  return;
5949 	case '@': semsg(_(e_cannot_declare_a_register_str), name);
5950 		  return;
5951 	default: return;
5952     }
5953     semsg(_(e_cannot_declare_a_scope_variable), scope, name);
5954 }
5955 
5956 /*
5957  * For one assignment figure out the type of destination.  Return it in "dest".
5958  * When not recognized "dest" is not set.
5959  * For an option "opt_flags" is set.
5960  * For a v:var "vimvaridx" is set.
5961  * "type" is set to the destination type if known, unchanted otherwise.
5962  * Return FAIL if an error message was given.
5963  */
5964     static int
5965 get_var_dest(
5966 	char_u		*name,
5967 	assign_dest_T	*dest,
5968 	int		cmdidx,
5969 	int		*opt_flags,
5970 	int		*vimvaridx,
5971 	type_T		**type,
5972 	cctx_T		*cctx)
5973 {
5974     char_u *p;
5975 
5976     if (*name == '&')
5977     {
5978 	int		cc;
5979 	long		numval;
5980 	getoption_T	opt_type;
5981 
5982 	*dest = dest_option;
5983 	if (cmdidx == CMD_final || cmdidx == CMD_const)
5984 	{
5985 	    emsg(_(e_const_option));
5986 	    return FAIL;
5987 	}
5988 	p = name;
5989 	p = find_option_end(&p, opt_flags);
5990 	if (p == NULL)
5991 	{
5992 	    // cannot happen?
5993 	    emsg(_(e_unexpected_characters_in_assignment));
5994 	    return FAIL;
5995 	}
5996 	cc = *p;
5997 	*p = NUL;
5998 	opt_type = get_option_value(skip_option_env_lead(name),
5999 						    &numval, NULL, *opt_flags);
6000 	*p = cc;
6001 	switch (opt_type)
6002 	{
6003 	    case gov_unknown:
6004 		    semsg(_(e_unknown_option), name);
6005 		    return FAIL;
6006 	    case gov_string:
6007 	    case gov_hidden_string:
6008 		    *type = &t_string;
6009 		    break;
6010 	    case gov_bool:
6011 	    case gov_hidden_bool:
6012 		    *type = &t_bool;
6013 		    break;
6014 	    case gov_number:
6015 	    case gov_hidden_number:
6016 		    *type = &t_number;
6017 		    break;
6018 	}
6019     }
6020     else if (*name == '$')
6021     {
6022 	*dest = dest_env;
6023 	*type = &t_string;
6024     }
6025     else if (*name == '@')
6026     {
6027 	if (name[1] != '@'
6028 			&& (!valid_yank_reg(name[1], FALSE) || name[1] == '.'))
6029 	{
6030 	    emsg_invreg(name[1]);
6031 	    return FAIL;
6032 	}
6033 	*dest = dest_reg;
6034 	*type = name[1] == '#' ? &t_number_or_string : &t_string;
6035     }
6036     else if (STRNCMP(name, "g:", 2) == 0)
6037     {
6038 	*dest = dest_global;
6039     }
6040     else if (STRNCMP(name, "b:", 2) == 0)
6041     {
6042 	*dest = dest_buffer;
6043     }
6044     else if (STRNCMP(name, "w:", 2) == 0)
6045     {
6046 	*dest = dest_window;
6047     }
6048     else if (STRNCMP(name, "t:", 2) == 0)
6049     {
6050 	*dest = dest_tab;
6051     }
6052     else if (STRNCMP(name, "v:", 2) == 0)
6053     {
6054 	typval_T	*vtv;
6055 	int		di_flags;
6056 
6057 	*vimvaridx = find_vim_var(name + 2, &di_flags);
6058 	if (*vimvaridx < 0)
6059 	{
6060 	    semsg(_(e_variable_not_found_str), name);
6061 	    return FAIL;
6062 	}
6063 	// We use the current value of "sandbox" here, is that OK?
6064 	if (var_check_ro(di_flags, name, FALSE))
6065 	    return FAIL;
6066 	*dest = dest_vimvar;
6067 	vtv = get_vim_var_tv(*vimvaridx);
6068 	*type = typval2type_vimvar(vtv, cctx->ctx_type_list);
6069     }
6070     return OK;
6071 }
6072 
6073 /*
6074  * Generate a STORE instruction for "dest", not being "dest_local".
6075  * Return FAIL when out of memory.
6076  */
6077     static int
6078 generate_store_var(
6079 	cctx_T		*cctx,
6080 	assign_dest_T	dest,
6081 	int		opt_flags,
6082 	int		vimvaridx,
6083 	int		scriptvar_idx,
6084 	int		scriptvar_sid,
6085 	type_T		*type,
6086 	char_u		*name)
6087 {
6088     switch (dest)
6089     {
6090 	case dest_option:
6091 	    return generate_STOREOPT(cctx, skip_option_env_lead(name),
6092 								    opt_flags);
6093 	case dest_global:
6094 	    // include g: with the name, easier to execute that way
6095 	    return generate_STORE(cctx, vim_strchr(name, AUTOLOAD_CHAR) == NULL
6096 					? ISN_STOREG : ISN_STOREAUTO, 0, name);
6097 	case dest_buffer:
6098 	    // include b: with the name, easier to execute that way
6099 	    return generate_STORE(cctx, ISN_STOREB, 0, name);
6100 	case dest_window:
6101 	    // include w: with the name, easier to execute that way
6102 	    return generate_STORE(cctx, ISN_STOREW, 0, name);
6103 	case dest_tab:
6104 	    // include t: with the name, easier to execute that way
6105 	    return generate_STORE(cctx, ISN_STORET, 0, name);
6106 	case dest_env:
6107 	    return generate_STORE(cctx, ISN_STOREENV, 0, name + 1);
6108 	case dest_reg:
6109 	    return generate_STORE(cctx, ISN_STOREREG,
6110 					 name[1] == '@' ? '"' : name[1], NULL);
6111 	case dest_vimvar:
6112 	    return generate_STORE(cctx, ISN_STOREV, vimvaridx, NULL);
6113 	case dest_script:
6114 	    if (scriptvar_idx < 0)
6115 		// "s:" may be included in the name.
6116 		return generate_OLDSCRIPT(cctx, ISN_STORES, name,
6117 							  scriptvar_sid, type);
6118 	    return generate_VIM9SCRIPT(cctx, ISN_STORESCRIPT,
6119 					   scriptvar_sid, scriptvar_idx, type);
6120 	case dest_local:
6121 	case dest_expr:
6122 	    // cannot happen
6123 	    break;
6124     }
6125     return FAIL;
6126 }
6127 
6128     static int
6129 generate_store_lhs(cctx_T *cctx, lhs_T *lhs, int instr_count)
6130 {
6131     if (lhs->lhs_dest != dest_local)
6132 	return generate_store_var(cctx, lhs->lhs_dest,
6133 			    lhs->lhs_opt_flags, lhs->lhs_vimvaridx,
6134 			    lhs->lhs_scriptvar_idx, lhs->lhs_scriptvar_sid,
6135 			    lhs->lhs_type, lhs->lhs_name);
6136 
6137     if (lhs->lhs_lvar != NULL)
6138     {
6139 	garray_T	*instr = &cctx->ctx_instr;
6140 	isn_T		*isn = ((isn_T *)instr->ga_data) + instr->ga_len - 1;
6141 
6142 	// optimization: turn "var = 123" from ISN_PUSHNR + ISN_STORE into
6143 	// ISN_STORENR
6144 	if (lhs->lhs_lvar->lv_from_outer == 0
6145 		&& instr->ga_len == instr_count + 1
6146 		&& isn->isn_type == ISN_PUSHNR)
6147 	{
6148 	    varnumber_T val = isn->isn_arg.number;
6149 	    garray_T    *stack = &cctx->ctx_type_stack;
6150 
6151 	    isn->isn_type = ISN_STORENR;
6152 	    isn->isn_arg.storenr.stnr_idx = lhs->lhs_lvar->lv_idx;
6153 	    isn->isn_arg.storenr.stnr_val = val;
6154 	    if (stack->ga_len > 0)
6155 		--stack->ga_len;
6156 	}
6157 	else if (lhs->lhs_lvar->lv_from_outer > 0)
6158 	    generate_STOREOUTER(cctx, lhs->lhs_lvar->lv_idx,
6159 						 lhs->lhs_lvar->lv_from_outer);
6160 	else
6161 	    generate_STORE(cctx, ISN_STORE, lhs->lhs_lvar->lv_idx, NULL);
6162     }
6163     return OK;
6164 }
6165 
6166     static int
6167 is_decl_command(int cmdidx)
6168 {
6169     return cmdidx == CMD_let || cmdidx == CMD_var
6170 				 || cmdidx == CMD_final || cmdidx == CMD_const;
6171 }
6172 
6173 /*
6174  * Figure out the LHS type and other properties for an assignment or one item
6175  * of ":unlet" with an index.
6176  * Returns OK or FAIL.
6177  */
6178     static int
6179 compile_lhs(
6180 	char_u	*var_start,
6181 	lhs_T	*lhs,
6182 	int	cmdidx,
6183 	int	heredoc,
6184 	int	oplen,
6185 	cctx_T	*cctx)
6186 {
6187     char_u	*var_end;
6188     int		is_decl = is_decl_command(cmdidx);
6189 
6190     CLEAR_POINTER(lhs);
6191     lhs->lhs_dest = dest_local;
6192     lhs->lhs_vimvaridx = -1;
6193     lhs->lhs_scriptvar_idx = -1;
6194 
6195     // "dest_end" is the end of the destination, including "[expr]" or
6196     // ".name".
6197     // "var_end" is the end of the variable/option/etc. name.
6198     lhs->lhs_dest_end = skip_var_one(var_start, FALSE);
6199     if (*var_start == '@')
6200 	var_end = var_start + 2;
6201     else
6202     {
6203 	// skip over the leading "&", "&l:", "&g:" and "$"
6204 	var_end = skip_option_env_lead(var_start);
6205 	var_end = to_name_end(var_end, TRUE);
6206     }
6207 
6208     // "a: type" is declaring variable "a" with a type, not dict "a:".
6209     if (is_decl && lhs->lhs_dest_end == var_start + 2
6210 					       && lhs->lhs_dest_end[-1] == ':')
6211 	--lhs->lhs_dest_end;
6212     if (is_decl && var_end == var_start + 2 && var_end[-1] == ':')
6213 	--var_end;
6214 
6215     // compute the length of the destination without "[expr]" or ".name"
6216     lhs->lhs_varlen = var_end - var_start;
6217     lhs->lhs_varlen_total = lhs->lhs_varlen;
6218     lhs->lhs_name = vim_strnsave(var_start, lhs->lhs_varlen);
6219     if (lhs->lhs_name == NULL)
6220 	return FAIL;
6221 
6222     if (lhs->lhs_dest_end > var_start + lhs->lhs_varlen)
6223 	// Something follows after the variable: "var[idx]" or "var.key".
6224 	lhs->lhs_has_index = TRUE;
6225 
6226     if (heredoc)
6227 	lhs->lhs_type = &t_list_string;
6228     else
6229 	lhs->lhs_type = &t_any;
6230 
6231     if (cctx->ctx_skip != SKIP_YES)
6232     {
6233 	int	    declare_error = FALSE;
6234 
6235 	if (get_var_dest(lhs->lhs_name, &lhs->lhs_dest, cmdidx,
6236 				      &lhs->lhs_opt_flags, &lhs->lhs_vimvaridx,
6237 						 &lhs->lhs_type, cctx) == FAIL)
6238 	    return FAIL;
6239 	if (lhs->lhs_dest != dest_local
6240 				 && cmdidx != CMD_const && cmdidx != CMD_final)
6241 	{
6242 	    // Specific kind of variable recognized.
6243 	    declare_error = is_decl;
6244 	}
6245 	else
6246 	{
6247 	    // No specific kind of variable recognized, just a name.
6248 	    if (check_reserved_name(lhs->lhs_name) == FAIL)
6249 		return FAIL;
6250 
6251 	    if (lookup_local(var_start, lhs->lhs_varlen,
6252 					     &lhs->lhs_local_lvar, cctx) == OK)
6253 		lhs->lhs_lvar = &lhs->lhs_local_lvar;
6254 	    else
6255 	    {
6256 		CLEAR_FIELD(lhs->lhs_arg_lvar);
6257 		if (arg_exists(var_start, lhs->lhs_varlen,
6258 			 &lhs->lhs_arg_lvar.lv_idx, &lhs->lhs_arg_lvar.lv_type,
6259 			    &lhs->lhs_arg_lvar.lv_from_outer, cctx) == OK)
6260 		{
6261 		    if (is_decl)
6262 		    {
6263 			semsg(_(e_str_is_used_as_argument), lhs->lhs_name);
6264 			return FAIL;
6265 		    }
6266 		    lhs->lhs_lvar = &lhs->lhs_arg_lvar;
6267 		}
6268 	    }
6269 	    if (lhs->lhs_lvar != NULL)
6270 	    {
6271 		if (is_decl)
6272 		{
6273 		    semsg(_(e_variable_already_declared), lhs->lhs_name);
6274 		    return FAIL;
6275 		}
6276 	    }
6277 	    else
6278 	    {
6279 		int script_namespace = lhs->lhs_varlen > 1
6280 				       && STRNCMP(var_start, "s:", 2) == 0;
6281 		int script_var = (script_namespace
6282 			? script_var_exists(var_start + 2, lhs->lhs_varlen - 2,
6283 									  cctx)
6284 			  : script_var_exists(var_start, lhs->lhs_varlen,
6285 								  cctx)) == OK;
6286 		imported_T  *import =
6287 			       find_imported(var_start, lhs->lhs_varlen, cctx);
6288 
6289 		if (script_namespace || script_var || import != NULL)
6290 		{
6291 		    char_u	*rawname = lhs->lhs_name
6292 					   + (lhs->lhs_name[1] == ':' ? 2 : 0);
6293 
6294 		    if (is_decl)
6295 		    {
6296 			if (script_namespace)
6297 			    semsg(_(e_cannot_declare_script_variable_in_function),
6298 								lhs->lhs_name);
6299 			else
6300 			    semsg(_(e_variable_already_declared_in_script_str),
6301 								lhs->lhs_name);
6302 			return FAIL;
6303 		    }
6304 		    else if (cctx->ctx_ufunc->uf_script_ctx_version
6305 							 == SCRIPT_VERSION_VIM9
6306 				    && script_namespace
6307 				    && !script_var && import == NULL)
6308 		    {
6309 			semsg(_(e_unknown_variable_str), lhs->lhs_name);
6310 			return FAIL;
6311 		    }
6312 
6313 		    lhs->lhs_dest = dest_script;
6314 
6315 		    // existing script-local variables should have a type
6316 		    lhs->lhs_scriptvar_sid = current_sctx.sc_sid;
6317 		    if (import != NULL)
6318 			lhs->lhs_scriptvar_sid = import->imp_sid;
6319 		    if (SCRIPT_ID_VALID(lhs->lhs_scriptvar_sid))
6320 		    {
6321 			// Check writable only when no index follows.
6322 			lhs->lhs_scriptvar_idx = get_script_item_idx(
6323 					       lhs->lhs_scriptvar_sid, rawname,
6324 			      lhs->lhs_has_index ? ASSIGN_FINAL : ASSIGN_CONST,
6325 									 cctx);
6326 			if (lhs->lhs_scriptvar_idx >= 0)
6327 			{
6328 			    scriptitem_T *si = SCRIPT_ITEM(
6329 						       lhs->lhs_scriptvar_sid);
6330 			    svar_T	 *sv =
6331 					    ((svar_T *)si->sn_var_vals.ga_data)
6332 						      + lhs->lhs_scriptvar_idx;
6333 			    lhs->lhs_type = sv->sv_type;
6334 			}
6335 		    }
6336 		}
6337 		else if (check_defined(var_start, lhs->lhs_varlen, cctx, FALSE)
6338 								       == FAIL)
6339 		    return FAIL;
6340 	    }
6341 	}
6342 
6343 	if (declare_error)
6344 	{
6345 	    vim9_declare_error(lhs->lhs_name);
6346 	    return FAIL;
6347 	}
6348     }
6349 
6350     // handle "a:name" as a name, not index "name" on "a"
6351     if (lhs->lhs_varlen > 1 || var_start[lhs->lhs_varlen] != ':')
6352 	var_end = lhs->lhs_dest_end;
6353 
6354     if (lhs->lhs_dest != dest_option)
6355     {
6356 	if (is_decl && *var_end == ':')
6357 	{
6358 	    char_u *p;
6359 
6360 	    // parse optional type: "let var: type = expr"
6361 	    if (!VIM_ISWHITE(var_end[1]))
6362 	    {
6363 		semsg(_(e_white_space_required_after_str_str), ":", var_end);
6364 		return FAIL;
6365 	    }
6366 	    p = skipwhite(var_end + 1);
6367 	    lhs->lhs_type = parse_type(&p, cctx->ctx_type_list, TRUE);
6368 	    if (lhs->lhs_type == NULL)
6369 		return FAIL;
6370 	    lhs->lhs_has_type = TRUE;
6371 	}
6372 	else if (lhs->lhs_lvar != NULL)
6373 	    lhs->lhs_type = lhs->lhs_lvar->lv_type;
6374     }
6375 
6376     if (oplen == 3 && !heredoc
6377 		   && lhs->lhs_dest != dest_global
6378 		   && !lhs->lhs_has_index
6379 		   && lhs->lhs_type->tt_type != VAR_STRING
6380 		   && lhs->lhs_type->tt_type != VAR_ANY)
6381     {
6382 	emsg(_(e_can_only_concatenate_to_string));
6383 	return FAIL;
6384     }
6385 
6386     if (lhs->lhs_lvar == NULL && lhs->lhs_dest == dest_local
6387 						 && cctx->ctx_skip != SKIP_YES)
6388     {
6389 	if (oplen > 1 && !heredoc)
6390 	{
6391 	    // +=, /=, etc. require an existing variable
6392 	    semsg(_(e_cannot_use_operator_on_new_variable), lhs->lhs_name);
6393 	    return FAIL;
6394 	}
6395 	if (!is_decl)
6396 	{
6397 	    semsg(_(e_unknown_variable_str), lhs->lhs_name);
6398 	    return FAIL;
6399 	}
6400 
6401 	// Check the name is valid for a funcref.
6402 	if ((lhs->lhs_type->tt_type == VAR_FUNC
6403 				      || lhs->lhs_type->tt_type == VAR_PARTIAL)
6404 		&& var_wrong_func_name(lhs->lhs_name, TRUE))
6405 	    return FAIL;
6406 
6407 	// New local variable.
6408 	lhs->lhs_lvar = reserve_local(cctx, var_start, lhs->lhs_varlen,
6409 		    cmdidx == CMD_final || cmdidx == CMD_const, lhs->lhs_type);
6410 	if (lhs->lhs_lvar == NULL)
6411 	    return FAIL;
6412 	lhs->lhs_new_local = TRUE;
6413     }
6414 
6415     lhs->lhs_member_type = lhs->lhs_type;
6416     if (lhs->lhs_has_index)
6417     {
6418 	// Something follows after the variable: "var[idx]" or "var.key".
6419 	// TODO: should we also handle "->func()" here?
6420 	if (is_decl)
6421 	{
6422 	    emsg(_(e_cannot_use_index_when_declaring_variable));
6423 	    return FAIL;
6424 	}
6425 
6426 	if (var_start[lhs->lhs_varlen] == '['
6427 					  || var_start[lhs->lhs_varlen] == '.')
6428 	{
6429 	    char_u	*after = var_start + lhs->lhs_varlen;
6430 	    char_u	*p;
6431 
6432 	    // Only the last index is used below, if there are others
6433 	    // before it generate code for the expression.  Thus for
6434 	    // "ll[1][2]" the expression is "ll[1]" and "[2]" is the index.
6435 	    for (;;)
6436 	    {
6437 		p = skip_index(after);
6438 		if (*p != '[' && *p != '.')
6439 		{
6440 		    lhs->lhs_varlen_total = p - var_start;
6441 		    break;
6442 		}
6443 		after = p;
6444 	    }
6445 	    if (after > var_start + lhs->lhs_varlen)
6446 	    {
6447 		lhs->lhs_varlen = after - var_start;
6448 		lhs->lhs_dest = dest_expr;
6449 		// We don't know the type before evaluating the expression,
6450 		// use "any" until then.
6451 		lhs->lhs_type = &t_any;
6452 	    }
6453 
6454 	    if (lhs->lhs_type->tt_member == NULL)
6455 		lhs->lhs_member_type = &t_any;
6456 	    else
6457 		lhs->lhs_member_type = lhs->lhs_type->tt_member;
6458 	}
6459 	else
6460 	{
6461 	    semsg("Not supported yet: %s", var_start);
6462 	    return FAIL;
6463 	}
6464     }
6465     return OK;
6466 }
6467 
6468 /*
6469  * Figure out the LHS and check a few errors.
6470  */
6471     static int
6472 compile_assign_lhs(
6473 	char_u	*var_start,
6474 	lhs_T	*lhs,
6475 	int	cmdidx,
6476 	int	is_decl,
6477 	int	heredoc,
6478 	int	oplen,
6479 	cctx_T	*cctx)
6480 {
6481     if (compile_lhs(var_start, lhs, cmdidx, heredoc, oplen, cctx) == FAIL)
6482 	return FAIL;
6483 
6484     if (!lhs->lhs_has_index && lhs->lhs_lvar == &lhs->lhs_arg_lvar)
6485     {
6486 	semsg(_(e_cannot_assign_to_argument), lhs->lhs_name);
6487 	return FAIL;
6488     }
6489     if (!is_decl && lhs->lhs_lvar != NULL
6490 			   && lhs->lhs_lvar->lv_const && !lhs->lhs_has_index)
6491     {
6492 	semsg(_(e_cannot_assign_to_constant), lhs->lhs_name);
6493 	return FAIL;
6494     }
6495     return OK;
6496 }
6497 
6498 /*
6499  * Return TRUE if "lhs" has a range index: "[expr : expr]".
6500  */
6501     static int
6502 has_list_index(char_u *idx_start, cctx_T *cctx)
6503 {
6504     char_u  *p = idx_start;
6505     int	    save_skip;
6506 
6507     if (*p != '[')
6508 	return FALSE;
6509 
6510     p = skipwhite(p + 1);
6511     if (*p == ':')
6512 	return TRUE;
6513 
6514     save_skip = cctx->ctx_skip;
6515     cctx->ctx_skip = SKIP_YES;
6516     (void)compile_expr0(&p, cctx);
6517     cctx->ctx_skip = save_skip;
6518     return *skipwhite(p) == ':';
6519 }
6520 
6521 /*
6522  * For an assignment with an index, compile the "idx" in "var[idx]" or "key" in
6523  * "var.key".
6524  */
6525     static int
6526 compile_assign_index(
6527 	char_u	*var_start,
6528 	lhs_T	*lhs,
6529 	int	*range,
6530 	cctx_T	*cctx)
6531 {
6532     size_t	varlen = lhs->lhs_varlen;
6533     char_u	*p;
6534     int		r = OK;
6535     int		need_white_before = TRUE;
6536     int		empty_second;
6537 
6538     p = var_start + varlen;
6539     if (*p == '[')
6540     {
6541 	p = skipwhite(p + 1);
6542 	if (*p == ':')
6543 	{
6544 	    // empty first index, push zero
6545 	    r = generate_PUSHNR(cctx, 0);
6546 	    need_white_before = FALSE;
6547 	}
6548 	else
6549 	    r = compile_expr0(&p, cctx);
6550 
6551 	if (r == OK && *skipwhite(p) == ':')
6552 	{
6553 	    // unlet var[idx : idx]
6554 	    // blob[idx : idx] = value
6555 	    *range = TRUE;
6556 	    p = skipwhite(p);
6557 	    empty_second = *skipwhite(p + 1) == ']';
6558 	    if ((need_white_before && !IS_WHITE_OR_NUL(p[-1]))
6559 		    || (!empty_second && !IS_WHITE_OR_NUL(p[1])))
6560 	    {
6561 		semsg(_(e_white_space_required_before_and_after_str_at_str),
6562 								      ":", p);
6563 		return FAIL;
6564 	    }
6565 	    p = skipwhite(p + 1);
6566 	    if (*p == ']')
6567 		// empty second index, push "none"
6568 		r = generate_PUSHSPEC(cctx, VVAL_NONE);
6569 	    else
6570 		r = compile_expr0(&p, cctx);
6571 	}
6572 
6573 	if (r == OK && *skipwhite(p) != ']')
6574 	{
6575 	    // this should not happen
6576 	    emsg(_(e_missbrac));
6577 	    r = FAIL;
6578 	}
6579     }
6580     else // if (*p == '.')
6581     {
6582 	char_u *key_end = to_name_end(p + 1, TRUE);
6583 	char_u *key = vim_strnsave(p + 1, key_end - p - 1);
6584 
6585 	r = generate_PUSHS(cctx, &key);
6586     }
6587     return r;
6588 }
6589 
6590 /*
6591  * For a LHS with an index, load the variable to be indexed.
6592  */
6593     static int
6594 compile_load_lhs(
6595 	lhs_T	*lhs,
6596 	char_u	*var_start,
6597 	type_T	*rhs_type,
6598 	cctx_T	*cctx)
6599 {
6600     if (lhs->lhs_dest == dest_expr)
6601     {
6602 	size_t	    varlen = lhs->lhs_varlen;
6603 	int	    c = var_start[varlen];
6604 	int	    lines_len = cctx->ctx_ufunc->uf_lines.ga_len;
6605 	char_u	    *p = var_start;
6606 	garray_T    *stack = &cctx->ctx_type_stack;
6607 	int	    res;
6608 
6609 	// Evaluate "ll[expr]" of "ll[expr][idx]".  End the line with a NUL and
6610 	// limit the lines array length to avoid skipping to a following line.
6611 	var_start[varlen] = NUL;
6612 	cctx->ctx_ufunc->uf_lines.ga_len = cctx->ctx_lnum + 1;
6613 	res = compile_expr0(&p, cctx);
6614 	var_start[varlen] = c;
6615 	cctx->ctx_ufunc->uf_lines.ga_len = lines_len;
6616 	if (res == FAIL || p != var_start + varlen)
6617 	{
6618 	    // this should not happen
6619 	    if (res != FAIL)
6620 		emsg(_(e_missbrac));
6621 	    return FAIL;
6622 	}
6623 
6624 	lhs->lhs_type = stack->ga_len == 0 ? &t_void
6625 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
6626 	// now we can properly check the type
6627 	if (rhs_type != NULL && lhs->lhs_type->tt_member != NULL
6628 		&& rhs_type != &t_void
6629 		&& need_type(rhs_type, lhs->lhs_type->tt_member, -2, 0, cctx,
6630 							 FALSE, FALSE) == FAIL)
6631 	    return FAIL;
6632     }
6633     else
6634 	generate_loadvar(cctx, lhs->lhs_dest, lhs->lhs_name,
6635 						 lhs->lhs_lvar, lhs->lhs_type);
6636     return OK;
6637 }
6638 
6639 /*
6640  * Produce code for loading "lhs" and also take care of an index.
6641  * Return OK/FAIL.
6642  */
6643     static int
6644 compile_load_lhs_with_index(lhs_T *lhs, char_u *var_start, cctx_T *cctx)
6645 {
6646     compile_load_lhs(lhs, var_start, NULL, cctx);
6647 
6648     if (lhs->lhs_has_index)
6649     {
6650 	int range = FALSE;
6651 
6652 	// Get member from list or dict.  First compile the
6653 	// index value.
6654 	if (compile_assign_index(var_start, lhs, &range, cctx) == FAIL)
6655 	    return FAIL;
6656 	if (range)
6657 	{
6658 	    semsg(_(e_cannot_use_range_with_assignment_operator_str),
6659 								    var_start);
6660 	    return FAIL;
6661 	}
6662 
6663 	// Get the member.
6664 	if (compile_member(FALSE, cctx) == FAIL)
6665 	    return FAIL;
6666     }
6667     return OK;
6668 }
6669 
6670 /*
6671  * Assignment to a list or dict member, or ":unlet" for the item, using the
6672  * information in "lhs".
6673  * Returns OK or FAIL.
6674  */
6675     static int
6676 compile_assign_unlet(
6677 	char_u	*var_start,
6678 	lhs_T	*lhs,
6679 	int	is_assign,
6680 	type_T	*rhs_type,
6681 	cctx_T	*cctx)
6682 {
6683     vartype_T	dest_type;
6684     garray_T    *stack = &cctx->ctx_type_stack;
6685     int		range = FALSE;
6686 
6687     if (compile_assign_index(var_start, lhs, &range, cctx) == FAIL)
6688 	return FAIL;
6689     if (is_assign && range
6690 	    && lhs->lhs_type->tt_type != VAR_LIST
6691 	    && lhs->lhs_type != &t_blob
6692 	    && lhs->lhs_type != &t_any)
6693     {
6694 	semsg(_(e_cannot_use_range_with_assignment_str), var_start);
6695 	return FAIL;
6696     }
6697 
6698     if (lhs->lhs_type == &t_any)
6699     {
6700 	// Index on variable of unknown type: check at runtime.
6701 	dest_type = VAR_ANY;
6702     }
6703     else
6704     {
6705 	dest_type = lhs->lhs_type->tt_type;
6706 	if (dest_type == VAR_DICT && range)
6707 	{
6708 	    emsg(e_cannot_use_range_with_dictionary);
6709 	    return FAIL;
6710 	}
6711 	if (dest_type == VAR_DICT
6712 			      && may_generate_2STRING(-1, FALSE, cctx) == FAIL)
6713 	    return FAIL;
6714 	if (dest_type == VAR_LIST || dest_type == VAR_BLOB)
6715 	{
6716 	    type_T *type;
6717 
6718 	    if (range)
6719 	    {
6720 		type = ((type_T **)stack->ga_data)[stack->ga_len - 2];
6721 		if (need_type(type, &t_number,
6722 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
6723 		return FAIL;
6724 	    }
6725 	    type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
6726 	    if ((dest_type != VAR_BLOB && type != &t_special)
6727 		    && need_type(type, &t_number,
6728 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
6729 		return FAIL;
6730 	}
6731     }
6732 
6733     // Load the dict or list.  On the stack we then have:
6734     // - value (for assignment, not for :unlet)
6735     // - index
6736     // - for [a : b] second index
6737     // - variable
6738     if (compile_load_lhs(lhs, var_start, rhs_type, cctx) == FAIL)
6739 	return FAIL;
6740 
6741     if (dest_type == VAR_LIST || dest_type == VAR_DICT
6742 			      || dest_type == VAR_BLOB || dest_type == VAR_ANY)
6743     {
6744 	if (is_assign)
6745 	{
6746 	    if (range)
6747 	    {
6748 		if (generate_instr_drop(cctx, ISN_STORERANGE, 4) == NULL)
6749 		    return FAIL;
6750 	    }
6751 	    else
6752 	    {
6753 		isn_T	*isn = generate_instr_drop(cctx, ISN_STOREINDEX, 3);
6754 
6755 		if (isn == NULL)
6756 		    return FAIL;
6757 		isn->isn_arg.vartype = dest_type;
6758 	    }
6759 	}
6760 	else if (range)
6761 	{
6762 	    if (generate_instr_drop(cctx, ISN_UNLETRANGE, 3) == NULL)
6763 		return FAIL;
6764 	}
6765 	else
6766 	{
6767 	    if (generate_instr_drop(cctx, ISN_UNLETINDEX, 2) == NULL)
6768 		return FAIL;
6769 	}
6770     }
6771     else
6772     {
6773 	emsg(_(e_indexable_type_required));
6774 	return FAIL;
6775     }
6776 
6777     return OK;
6778 }
6779 
6780 /*
6781  * Compile declaration and assignment:
6782  * "let name"
6783  * "var name = expr"
6784  * "final name = expr"
6785  * "const name = expr"
6786  * "name = expr"
6787  * "arg" points to "name".
6788  * "++arg" and "--arg"
6789  * Return NULL for an error.
6790  * Return "arg" if it does not look like a variable list.
6791  */
6792     static char_u *
6793 compile_assignment(char_u *arg, exarg_T *eap, cmdidx_T cmdidx, cctx_T *cctx)
6794 {
6795     char_u	*var_start;
6796     char_u	*p;
6797     char_u	*end = arg;
6798     char_u	*ret = NULL;
6799     int		var_count = 0;
6800     int		var_idx;
6801     int		semicolon = 0;
6802     int		did_generate_slice = FALSE;
6803     garray_T	*instr = &cctx->ctx_instr;
6804     garray_T    *stack = &cctx->ctx_type_stack;
6805     char_u	*op;
6806     int		oplen = 0;
6807     int		heredoc = FALSE;
6808     int		incdec = FALSE;
6809     type_T	*rhs_type = &t_any;
6810     char_u	*sp;
6811     int		is_decl = is_decl_command(cmdidx);
6812     lhs_T	lhs;
6813     long	start_lnum = SOURCING_LNUM;
6814 
6815     // Skip over the "var" or "[var, var]" to get to any "=".
6816     p = skip_var_list(arg, TRUE, &var_count, &semicolon, TRUE);
6817     if (p == NULL)
6818 	return *arg == '[' ? arg : NULL;
6819 
6820     if (var_count > 0 && is_decl)
6821     {
6822 	// TODO: should we allow this, and figure out type inference from list
6823 	// members?
6824 	emsg(_(e_cannot_use_list_for_declaration));
6825 	return NULL;
6826     }
6827     lhs.lhs_name = NULL;
6828 
6829     sp = p;
6830     p = skipwhite(p);
6831     op = p;
6832     oplen = assignment_len(p, &heredoc);
6833 
6834     if (var_count > 0 && oplen == 0)
6835 	// can be something like "[1, 2]->func()"
6836 	return arg;
6837 
6838     if (oplen > 0 && (!VIM_ISWHITE(*sp) || !IS_WHITE_OR_NUL(op[oplen])))
6839     {
6840 	error_white_both(op, oplen);
6841 	return NULL;
6842     }
6843     if (eap->cmdidx == CMD_increment || eap->cmdidx == CMD_decrement)
6844     {
6845 	if (VIM_ISWHITE(eap->cmd[2]))
6846 	{
6847 	    semsg(_(e_no_white_space_allowed_after_str_str),
6848 			 eap->cmdidx == CMD_increment ? "++" : "--", eap->cmd);
6849 	    return NULL;
6850 	}
6851 	op = (char_u *)(eap->cmdidx == CMD_increment ? "+=" : "-=");
6852 	oplen = 2;
6853 	incdec = TRUE;
6854     }
6855 
6856     if (heredoc)
6857     {
6858 	list_T	   *l;
6859 	listitem_T *li;
6860 
6861 	// [let] varname =<< [trim] {end}
6862 	eap->getline = exarg_getline;
6863 	eap->cookie = cctx;
6864 	l = heredoc_get(eap, op + 3, FALSE);
6865 	if (l == NULL)
6866 	    return NULL;
6867 
6868 	if (cctx->ctx_skip != SKIP_YES)
6869 	{
6870 	    // Push each line and the create the list.
6871 	    FOR_ALL_LIST_ITEMS(l, li)
6872 	    {
6873 		generate_PUSHS(cctx, &li->li_tv.vval.v_string);
6874 		li->li_tv.vval.v_string = NULL;
6875 	    }
6876 	    generate_NEWLIST(cctx, l->lv_len);
6877 	}
6878 	list_free(l);
6879 	p += STRLEN(p);
6880 	end = p;
6881     }
6882     else if (var_count > 0)
6883     {
6884 	char_u *wp;
6885 
6886 	// for "[var, var] = expr" evaluate the expression here, loop over the
6887 	// list of variables below.
6888 	// A line break may follow the "=".
6889 
6890 	wp = op + oplen;
6891 	if (may_get_next_line_error(wp, &p, cctx) == FAIL)
6892 	    return FAIL;
6893 	if (compile_expr0(&p, cctx) == FAIL)
6894 	    return NULL;
6895 	end = p;
6896 
6897 	if (cctx->ctx_skip != SKIP_YES)
6898 	{
6899 	    type_T	*stacktype;
6900 
6901 	    stacktype = stack->ga_len == 0 ? &t_void
6902 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
6903 	    if (stacktype->tt_type == VAR_VOID)
6904 	    {
6905 		emsg(_(e_cannot_use_void_value));
6906 		goto theend;
6907 	    }
6908 	    if (need_type(stacktype, &t_list_any, -1, 0, cctx,
6909 							 FALSE, FALSE) == FAIL)
6910 		goto theend;
6911 	    // TODO: check the length of a constant list here
6912 	    generate_CHECKLEN(cctx, semicolon ? var_count - 1 : var_count,
6913 								    semicolon);
6914 	    if (stacktype->tt_member != NULL)
6915 		rhs_type = stacktype->tt_member;
6916 	}
6917     }
6918 
6919     /*
6920      * Loop over variables in "[var, var] = expr".
6921      * For "var = expr" and "let var: type" this is done only once.
6922      */
6923     if (var_count > 0)
6924 	var_start = skipwhite(arg + 1);  // skip over the "["
6925     else
6926 	var_start = arg;
6927     for (var_idx = 0; var_idx == 0 || var_idx < var_count; var_idx++)
6928     {
6929 	int	instr_count = -1;
6930 	int	save_lnum;
6931 
6932 	if (var_start[0] == '_' && !eval_isnamec(var_start[1]))
6933 	{
6934 	    // Ignore underscore in "[a, _, b] = list".
6935 	    if (var_count > 0)
6936 	    {
6937 		var_start = skipwhite(var_start + 2);
6938 		continue;
6939 	    }
6940 	    emsg(_(e_cannot_use_underscore_here));
6941 	    goto theend;
6942 	}
6943 	vim_free(lhs.lhs_name);
6944 
6945 	/*
6946 	 * Figure out the LHS type and other properties.
6947 	 */
6948 	if (compile_assign_lhs(var_start, &lhs, cmdidx,
6949 					is_decl, heredoc, oplen, cctx) == FAIL)
6950 	    goto theend;
6951 	if (heredoc)
6952 	{
6953 	    SOURCING_LNUM = start_lnum;
6954 	    if (lhs.lhs_has_type
6955 		    && need_type(&t_list_string, lhs.lhs_type,
6956 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
6957 		goto theend;
6958 	}
6959 	else
6960 	{
6961 	    if (cctx->ctx_skip == SKIP_YES)
6962 	    {
6963 		if (oplen > 0 && var_count == 0)
6964 		{
6965 		    // skip over the "=" and the expression
6966 		    p = skipwhite(op + oplen);
6967 		    (void)compile_expr0(&p, cctx);
6968 		}
6969 	    }
6970 	    else if (oplen > 0)
6971 	    {
6972 		int	is_const = FALSE;
6973 		char_u	*wp;
6974 
6975 		// for "+=", "*=", "..=" etc. first load the current value
6976 		if (*op != '='
6977 			&& compile_load_lhs_with_index(&lhs, var_start,
6978 								 cctx) == FAIL)
6979 		    goto theend;
6980 
6981 		// For "var = expr" evaluate the expression.
6982 		if (var_count == 0)
6983 		{
6984 		    int	r;
6985 
6986 		    // Compile the expression.
6987 		    instr_count = instr->ga_len;
6988 		    if (incdec)
6989 		    {
6990 			r = generate_PUSHNR(cctx, 1);
6991 		    }
6992 		    else
6993 		    {
6994 			// Temporarily hide the new local variable here, it is
6995 			// not available to this expression.
6996 			if (lhs.lhs_new_local)
6997 			    --cctx->ctx_locals.ga_len;
6998 			wp = op + oplen;
6999 			if (may_get_next_line_error(wp, &p, cctx) == FAIL)
7000 			{
7001 			    if (lhs.lhs_new_local)
7002 				++cctx->ctx_locals.ga_len;
7003 			    goto theend;
7004 			}
7005 			r = compile_expr0_ext(&p, cctx, &is_const);
7006 			if (lhs.lhs_new_local)
7007 			    ++cctx->ctx_locals.ga_len;
7008 			if (r == FAIL)
7009 			    goto theend;
7010 		    }
7011 		}
7012 		else if (semicolon && var_idx == var_count - 1)
7013 		{
7014 		    // For "[var; var] = expr" get the rest of the list
7015 		    did_generate_slice = TRUE;
7016 		    if (generate_SLICE(cctx, var_count - 1) == FAIL)
7017 			goto theend;
7018 		}
7019 		else
7020 		{
7021 		    // For "[var, var] = expr" get the "var_idx" item from the
7022 		    // list.
7023 		    if (generate_GETITEM(cctx, var_idx, *op != '=') == FAIL)
7024 			goto theend;
7025 		}
7026 
7027 		rhs_type = stack->ga_len == 0 ? &t_void
7028 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
7029 		if (lhs.lhs_lvar != NULL && (is_decl || !lhs.lhs_has_type))
7030 		{
7031 		    if ((rhs_type->tt_type == VAR_FUNC
7032 				|| rhs_type->tt_type == VAR_PARTIAL)
7033 			    && !lhs.lhs_has_index
7034 			    && var_wrong_func_name(lhs.lhs_name, TRUE))
7035 			goto theend;
7036 
7037 		    if (lhs.lhs_new_local && !lhs.lhs_has_type)
7038 		    {
7039 			if (rhs_type->tt_type == VAR_VOID)
7040 			{
7041 			    emsg(_(e_cannot_use_void_value));
7042 			    goto theend;
7043 			}
7044 			else
7045 			{
7046 			    // An empty list or dict has a &t_unknown member,
7047 			    // for a variable that implies &t_any.
7048 			    if (rhs_type == &t_list_empty)
7049 				lhs.lhs_lvar->lv_type = &t_list_any;
7050 			    else if (rhs_type == &t_dict_empty)
7051 				lhs.lhs_lvar->lv_type = &t_dict_any;
7052 			    else if (rhs_type == &t_unknown)
7053 				lhs.lhs_lvar->lv_type = &t_any;
7054 			    else
7055 				lhs.lhs_lvar->lv_type = rhs_type;
7056 			}
7057 		    }
7058 		    else if (*op == '=')
7059 		    {
7060 			type_T *use_type = lhs.lhs_lvar->lv_type;
7061 			where_T where = WHERE_INIT;
7062 
7063 			// Without operator check type here, otherwise below.
7064 			// Use the line number of the assignment.
7065 			SOURCING_LNUM = start_lnum;
7066 			where.wt_index = var_count > 0 ? var_idx + 1 : 0;
7067 			where.wt_variable = var_count > 0;
7068 			// If assigning to a list or dict member, use the
7069 			// member type.  Not for "list[:] =".
7070 			if (lhs.lhs_has_index
7071 				&& !has_list_index(var_start + lhs.lhs_varlen,
7072 									 cctx))
7073 			    use_type = lhs.lhs_member_type;
7074 			if (need_type_where(rhs_type, use_type, -1, where,
7075 				    cctx, FALSE, is_const) == FAIL)
7076 			    goto theend;
7077 		    }
7078 		}
7079 		else
7080 		{
7081 		    type_T *lhs_type = lhs.lhs_member_type;
7082 
7083 		    // Special case: assigning to @# can use a number or a
7084 		    // string.
7085 		    // Also: can assign a number to a float.
7086 		    if ((lhs_type == &t_number_or_string
7087 				|| lhs_type == &t_float)
7088 			    && rhs_type->tt_type == VAR_NUMBER)
7089 			lhs_type = &t_number;
7090 		    if (*p != '=' && need_type(rhs_type, lhs_type,
7091 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
7092 		    goto theend;
7093 		}
7094 	    }
7095 	    else if (cmdidx == CMD_final)
7096 	    {
7097 		emsg(_(e_final_requires_a_value));
7098 		goto theend;
7099 	    }
7100 	    else if (cmdidx == CMD_const)
7101 	    {
7102 		emsg(_(e_const_requires_a_value));
7103 		goto theend;
7104 	    }
7105 	    else if (!lhs.lhs_has_type || lhs.lhs_dest == dest_option)
7106 	    {
7107 		emsg(_(e_type_or_initialization_required));
7108 		goto theend;
7109 	    }
7110 	    else
7111 	    {
7112 		// variables are always initialized
7113 		if (GA_GROW_FAILS(instr, 1))
7114 		    goto theend;
7115 		switch (lhs.lhs_member_type->tt_type)
7116 		{
7117 		    case VAR_BOOL:
7118 			generate_PUSHBOOL(cctx, VVAL_FALSE);
7119 			break;
7120 		    case VAR_FLOAT:
7121 #ifdef FEAT_FLOAT
7122 			generate_PUSHF(cctx, 0.0);
7123 #endif
7124 			break;
7125 		    case VAR_STRING:
7126 			generate_PUSHS(cctx, NULL);
7127 			break;
7128 		    case VAR_BLOB:
7129 			generate_PUSHBLOB(cctx, blob_alloc());
7130 			break;
7131 		    case VAR_FUNC:
7132 			generate_PUSHFUNC(cctx, NULL, &t_func_void);
7133 			break;
7134 		    case VAR_LIST:
7135 			generate_NEWLIST(cctx, 0);
7136 			break;
7137 		    case VAR_DICT:
7138 			generate_NEWDICT(cctx, 0);
7139 			break;
7140 		    case VAR_JOB:
7141 			generate_PUSHJOB(cctx, NULL);
7142 			break;
7143 		    case VAR_CHANNEL:
7144 			generate_PUSHCHANNEL(cctx, NULL);
7145 			break;
7146 		    case VAR_NUMBER:
7147 		    case VAR_UNKNOWN:
7148 		    case VAR_ANY:
7149 		    case VAR_PARTIAL:
7150 		    case VAR_VOID:
7151 		    case VAR_INSTR:
7152 		    case VAR_SPECIAL:  // cannot happen
7153 			generate_PUSHNR(cctx, 0);
7154 			break;
7155 		}
7156 	    }
7157 	    if (var_count == 0)
7158 		end = p;
7159 	}
7160 
7161 	// no need to parse more when skipping
7162 	if (cctx->ctx_skip == SKIP_YES)
7163 	    break;
7164 
7165 	if (oplen > 0 && *op != '=')
7166 	{
7167 	    type_T	    *expected;
7168 	    type_T	    *stacktype = NULL;
7169 
7170 	    if (*op == '.')
7171 	    {
7172 		if (may_generate_2STRING(-1, FALSE, cctx) == FAIL)
7173 		    goto theend;
7174 	    }
7175 	    else
7176 	    {
7177 		expected = lhs.lhs_member_type;
7178 		stacktype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
7179 		if (
7180 #ifdef FEAT_FLOAT
7181 		    // If variable is float operation with number is OK.
7182 		    !(expected == &t_float && (stacktype == &t_number
7183 			    || stacktype == &t_number_bool)) &&
7184 #endif
7185 		    need_type(stacktype, expected, -1, 0, cctx,
7186 							 FALSE, FALSE) == FAIL)
7187 		    goto theend;
7188 	    }
7189 
7190 	    if (*op == '.')
7191 	    {
7192 		if (generate_instr_drop(cctx, ISN_CONCAT, 1) == NULL)
7193 		    goto theend;
7194 	    }
7195 	    else if (*op == '+')
7196 	    {
7197 		if (generate_add_instr(cctx,
7198 			    operator_type(lhs.lhs_member_type, stacktype),
7199 				       lhs.lhs_member_type, stacktype,
7200 							  EXPR_APPEND) == FAIL)
7201 		    goto theend;
7202 	    }
7203 	    else if (generate_two_op(cctx, op) == FAIL)
7204 		goto theend;
7205 	}
7206 
7207 	// Use the line number of the assignment for store instruction.
7208 	save_lnum = cctx->ctx_lnum;
7209 	cctx->ctx_lnum = start_lnum - 1;
7210 
7211 	if (lhs.lhs_has_index)
7212 	{
7213 	    // Use the info in "lhs" to store the value at the index in the
7214 	    // list or dict.
7215 	    if (compile_assign_unlet(var_start, &lhs, TRUE, rhs_type, cctx)
7216 								       == FAIL)
7217 	    {
7218 		cctx->ctx_lnum = save_lnum;
7219 		goto theend;
7220 	    }
7221 	}
7222 	else
7223 	{
7224 	    if (is_decl && cmdidx == CMD_const && (lhs.lhs_dest == dest_script
7225 						|| lhs.lhs_dest == dest_global
7226 						|| lhs.lhs_dest == dest_local))
7227 		// ":const var": lock the value, but not referenced variables
7228 		generate_LOCKCONST(cctx);
7229 
7230 	    if (is_decl
7231 		    && (lhs.lhs_type->tt_type == VAR_DICT
7232 					  || lhs.lhs_type->tt_type == VAR_LIST)
7233 		    && lhs.lhs_type->tt_member != NULL
7234 		    && !(lhs.lhs_type->tt_member == &t_any
7235 			    && oplen > 0
7236 			    && rhs_type != NULL
7237 			    && rhs_type->tt_type == lhs.lhs_type->tt_type
7238 			    && rhs_type->tt_member != &t_unknown)
7239 		    && lhs.lhs_type->tt_member != &t_unknown)
7240 		// Set the type in the list or dict, so that it can be checked,
7241 		// also in legacy script.  Not for "list<any> = val", then the
7242 		// type of "val" is used.
7243 		generate_SETTYPE(cctx, lhs.lhs_type);
7244 
7245 	    if (generate_store_lhs(cctx, &lhs, instr_count) == FAIL)
7246 	    {
7247 		cctx->ctx_lnum = save_lnum;
7248 		goto theend;
7249 	    }
7250 	}
7251 	cctx->ctx_lnum = save_lnum;
7252 
7253 	if (var_idx + 1 < var_count)
7254 	    var_start = skipwhite(lhs.lhs_dest_end + 1);
7255     }
7256 
7257     // For "[var, var] = expr" drop the "expr" value.
7258     // Also for "[var, var; _] = expr".
7259     if (var_count > 0 && (!semicolon || !did_generate_slice))
7260     {
7261 	if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
7262 	    goto theend;
7263     }
7264 
7265     ret = skipwhite(end);
7266 
7267 theend:
7268     vim_free(lhs.lhs_name);
7269     return ret;
7270 }
7271 
7272 /*
7273  * Check for an assignment at "eap->cmd", compile it if found.
7274  * Return NOTDONE if there is none, FAIL for failure, OK if done.
7275  */
7276     static int
7277 may_compile_assignment(exarg_T *eap, char_u **line, cctx_T *cctx)
7278 {
7279     char_u  *pskip;
7280     char_u  *p;
7281 
7282     // Assuming the command starts with a variable or function name,
7283     // find what follows.
7284     // Skip over "var.member", "var[idx]" and the like.
7285     // Also "&opt = val", "$ENV = val" and "@r = val".
7286     pskip = (*eap->cmd == '&' || *eap->cmd == '$' || *eap->cmd == '@')
7287 						 ? eap->cmd + 1 : eap->cmd;
7288     p = to_name_end(pskip, TRUE);
7289     if (p > eap->cmd && *p != NUL)
7290     {
7291 	char_u *var_end;
7292 	int	oplen;
7293 	int	heredoc;
7294 
7295 	if (eap->cmd[0] == '@')
7296 	    var_end = eap->cmd + 2;
7297 	else
7298 	    var_end = find_name_end(pskip, NULL, NULL,
7299 					FNE_CHECK_START | FNE_INCL_BR);
7300 	oplen = assignment_len(skipwhite(var_end), &heredoc);
7301 	if (oplen > 0)
7302 	{
7303 	    size_t len = p - eap->cmd;
7304 
7305 	    // Recognize an assignment if we recognize the variable
7306 	    // name:
7307 	    // "g:var = expr"
7308 	    // "local = expr"  where "local" is a local var.
7309 	    // "script = expr"  where "script" is a script-local var.
7310 	    // "import = expr"  where "import" is an imported var
7311 	    // "&opt = expr"
7312 	    // "$ENV = expr"
7313 	    // "@r = expr"
7314 	    if (*eap->cmd == '&'
7315 		    || *eap->cmd == '$'
7316 		    || *eap->cmd == '@'
7317 		    || ((len) > 2 && eap->cmd[1] == ':')
7318 		    || variable_exists(eap->cmd, len, cctx))
7319 	    {
7320 		*line = compile_assignment(eap->cmd, eap, CMD_SIZE, cctx);
7321 		if (*line == NULL || *line == eap->cmd)
7322 		    return FAIL;
7323 		return OK;
7324 	    }
7325 	}
7326     }
7327 
7328     if (*eap->cmd == '[')
7329     {
7330 	// [var, var] = expr
7331 	*line = compile_assignment(eap->cmd, eap, CMD_SIZE, cctx);
7332 	if (*line == NULL)
7333 	    return FAIL;
7334 	if (*line != eap->cmd)
7335 	    return OK;
7336     }
7337     return NOTDONE;
7338 }
7339 
7340 /*
7341  * Check if "name" can be "unlet".
7342  */
7343     int
7344 check_vim9_unlet(char_u *name)
7345 {
7346     if (name[1] != ':' || vim_strchr((char_u *)"gwtb", *name) == NULL)
7347     {
7348 	// "unlet s:var" is allowed in legacy script.
7349 	if (*name == 's' && !script_is_vim9())
7350 	    return OK;
7351 	semsg(_(e_cannot_unlet_str), name);
7352 	return FAIL;
7353     }
7354     return OK;
7355 }
7356 
7357 /*
7358  * Callback passed to ex_unletlock().
7359  */
7360     static int
7361 compile_unlet(
7362     lval_T  *lvp,
7363     char_u  *name_end,
7364     exarg_T *eap,
7365     int	    deep UNUSED,
7366     void    *coookie)
7367 {
7368     cctx_T	*cctx = coookie;
7369     char_u	*p = lvp->ll_name;
7370     int		cc = *name_end;
7371     int		ret = OK;
7372 
7373     if (cctx->ctx_skip == SKIP_YES)
7374 	return OK;
7375 
7376     *name_end = NUL;
7377     if (*p == '$')
7378     {
7379 	// :unlet $ENV_VAR
7380 	ret = generate_UNLET(cctx, ISN_UNLETENV, p + 1, eap->forceit);
7381     }
7382     else if (vim_strchr(p, '.') != NULL || vim_strchr(p, '[') != NULL)
7383     {
7384 	lhs_T	    lhs;
7385 
7386 	// This is similar to assigning: lookup the list/dict, compile the
7387 	// idx/key.  Then instead of storing the value unlet the item.
7388 	// unlet {list}[idx]
7389 	// unlet {dict}[key]  dict.key
7390 	//
7391 	// Figure out the LHS type and other properties.
7392 	//
7393 	ret = compile_lhs(p, &lhs, CMD_unlet, FALSE, 0, cctx);
7394 
7395 	// : unlet an indexed item
7396 	if (!lhs.lhs_has_index)
7397 	{
7398 	    iemsg("called compile_lhs() without an index");
7399 	    ret = FAIL;
7400 	}
7401 	else
7402 	{
7403 	    // Use the info in "lhs" to unlet the item at the index in the
7404 	    // list or dict.
7405 	    ret = compile_assign_unlet(p, &lhs, FALSE, &t_void, cctx);
7406 	}
7407 
7408 	vim_free(lhs.lhs_name);
7409     }
7410     else if (check_vim9_unlet(p) == FAIL)
7411     {
7412 	ret = FAIL;
7413     }
7414     else
7415     {
7416 	// Normal name.  Only supports g:, w:, t: and b: namespaces.
7417 	ret = generate_UNLET(cctx, ISN_UNLET, p, eap->forceit);
7418     }
7419 
7420     *name_end = cc;
7421     return ret;
7422 }
7423 
7424 /*
7425  * Callback passed to ex_unletlock().
7426  */
7427     static int
7428 compile_lock_unlock(
7429     lval_T  *lvp,
7430     char_u  *name_end,
7431     exarg_T *eap,
7432     int	    deep UNUSED,
7433     void    *coookie)
7434 {
7435     cctx_T	*cctx = coookie;
7436     int		cc = *name_end;
7437     char_u	*p = lvp->ll_name;
7438     int		ret = OK;
7439     size_t	len;
7440     char_u	*buf;
7441     isntype_T	isn = ISN_EXEC;
7442 
7443     if (cctx->ctx_skip == SKIP_YES)
7444 	return OK;
7445 
7446     // Cannot use :lockvar and :unlockvar on local variables.
7447     if (p[1] != ':')
7448     {
7449 	char_u *end = find_name_end(p, NULL, NULL, FNE_CHECK_START);
7450 
7451 	if (lookup_local(p, end - p, NULL, cctx) == OK)
7452 	{
7453 	    char_u *s = p;
7454 
7455 	    if (*end != '.' && *end != '[')
7456 	    {
7457 		emsg(_(e_cannot_lock_unlock_local_variable));
7458 		return FAIL;
7459 	    }
7460 
7461 	    // For "d.member" put the local variable on the stack, it will be
7462 	    // passed to ex_lockvar() indirectly.
7463 	    if (compile_load(&s, end, cctx, FALSE, FALSE) == FAIL)
7464 		return FAIL;
7465 	    isn = ISN_LOCKUNLOCK;
7466 	}
7467     }
7468 
7469     // Checking is done at runtime.
7470     *name_end = NUL;
7471     len = name_end - p + 20;
7472     buf = alloc(len);
7473     if (buf == NULL)
7474 	ret = FAIL;
7475     else
7476     {
7477 	vim_snprintf((char *)buf, len, "%s %s",
7478 		eap->cmdidx == CMD_lockvar ? "lockvar" : "unlockvar",
7479 		p);
7480 	ret = generate_EXEC(cctx, isn, buf);
7481 
7482 	vim_free(buf);
7483 	*name_end = cc;
7484     }
7485     return ret;
7486 }
7487 
7488 /*
7489  * compile "unlet var", "lock var" and "unlock var"
7490  * "arg" points to "var".
7491  */
7492     static char_u *
7493 compile_unletlock(char_u *arg, exarg_T *eap, cctx_T *cctx)
7494 {
7495     ex_unletlock(eap, arg, 0, GLV_NO_AUTOLOAD | GLV_COMPILING,
7496 	    eap->cmdidx == CMD_unlet ? compile_unlet : compile_lock_unlock,
7497 	    cctx);
7498     return eap->nextcmd == NULL ? (char_u *)"" : eap->nextcmd;
7499 }
7500 
7501 /*
7502  * generate a jump to the ":endif"/":endfor"/":endwhile"/":finally"/":endtry".
7503  */
7504     static int
7505 compile_jump_to_end(endlabel_T **el, jumpwhen_T when, cctx_T *cctx)
7506 {
7507     garray_T	*instr = &cctx->ctx_instr;
7508     endlabel_T  *endlabel = ALLOC_CLEAR_ONE(endlabel_T);
7509 
7510     if (endlabel == NULL)
7511 	return FAIL;
7512     endlabel->el_next = *el;
7513     *el = endlabel;
7514     endlabel->el_end_label = instr->ga_len;
7515 
7516     generate_JUMP(cctx, when, 0);
7517     return OK;
7518 }
7519 
7520     static void
7521 compile_fill_jump_to_end(endlabel_T **el, int jump_where, cctx_T *cctx)
7522 {
7523     garray_T	*instr = &cctx->ctx_instr;
7524 
7525     while (*el != NULL)
7526     {
7527 	endlabel_T  *cur = (*el);
7528 	isn_T	    *isn;
7529 
7530 	isn = ((isn_T *)instr->ga_data) + cur->el_end_label;
7531 	isn->isn_arg.jump.jump_where = jump_where;
7532 	*el = cur->el_next;
7533 	vim_free(cur);
7534     }
7535 }
7536 
7537     static void
7538 compile_free_jump_to_end(endlabel_T **el)
7539 {
7540     while (*el != NULL)
7541     {
7542 	endlabel_T  *cur = (*el);
7543 
7544 	*el = cur->el_next;
7545 	vim_free(cur);
7546     }
7547 }
7548 
7549 /*
7550  * Create a new scope and set up the generic items.
7551  */
7552     static scope_T *
7553 new_scope(cctx_T *cctx, scopetype_T type)
7554 {
7555     scope_T *scope = ALLOC_CLEAR_ONE(scope_T);
7556 
7557     if (scope == NULL)
7558 	return NULL;
7559     scope->se_outer = cctx->ctx_scope;
7560     cctx->ctx_scope = scope;
7561     scope->se_type = type;
7562     scope->se_local_count = cctx->ctx_locals.ga_len;
7563     return scope;
7564 }
7565 
7566 /*
7567  * Free the current scope and go back to the outer scope.
7568  */
7569     static void
7570 drop_scope(cctx_T *cctx)
7571 {
7572     scope_T *scope = cctx->ctx_scope;
7573 
7574     if (scope == NULL)
7575     {
7576 	iemsg("calling drop_scope() without a scope");
7577 	return;
7578     }
7579     cctx->ctx_scope = scope->se_outer;
7580     switch (scope->se_type)
7581     {
7582 	case IF_SCOPE:
7583 	    compile_free_jump_to_end(&scope->se_u.se_if.is_end_label); break;
7584 	case FOR_SCOPE:
7585 	    compile_free_jump_to_end(&scope->se_u.se_for.fs_end_label); break;
7586 	case WHILE_SCOPE:
7587 	    compile_free_jump_to_end(&scope->se_u.se_while.ws_end_label); break;
7588 	case TRY_SCOPE:
7589 	    compile_free_jump_to_end(&scope->se_u.se_try.ts_end_label); break;
7590 	case NO_SCOPE:
7591 	case BLOCK_SCOPE:
7592 	    break;
7593     }
7594     vim_free(scope);
7595 }
7596 
7597 /*
7598  * compile "if expr"
7599  *
7600  * "if expr" Produces instructions:
7601  *	EVAL expr		Push result of "expr"
7602  *	JUMP_IF_FALSE end
7603  *	... body ...
7604  * end:
7605  *
7606  * "if expr | else" Produces instructions:
7607  *	EVAL expr		Push result of "expr"
7608  *	JUMP_IF_FALSE else
7609  *	... body ...
7610  *	JUMP_ALWAYS end
7611  * else:
7612  *	... body ...
7613  * end:
7614  *
7615  * "if expr1 | elseif expr2 | else" Produces instructions:
7616  *	EVAL expr		Push result of "expr"
7617  *	JUMP_IF_FALSE elseif
7618  *	... body ...
7619  *	JUMP_ALWAYS end
7620  * elseif:
7621  *	EVAL expr		Push result of "expr"
7622  *	JUMP_IF_FALSE else
7623  *	... body ...
7624  *	JUMP_ALWAYS end
7625  * else:
7626  *	... body ...
7627  * end:
7628  */
7629     static char_u *
7630 compile_if(char_u *arg, cctx_T *cctx)
7631 {
7632     char_u	*p = arg;
7633     garray_T	*instr = &cctx->ctx_instr;
7634     int		instr_count = instr->ga_len;
7635     scope_T	*scope;
7636     skip_T	skip_save = cctx->ctx_skip;
7637     ppconst_T	ppconst;
7638 
7639     CLEAR_FIELD(ppconst);
7640     if (compile_expr1(&p, cctx, &ppconst) == FAIL)
7641     {
7642 	clear_ppconst(&ppconst);
7643 	return NULL;
7644     }
7645     if (!ends_excmd2(arg, skipwhite(p)))
7646     {
7647 	semsg(_(e_trailing_arg), p);
7648 	return NULL;
7649     }
7650     if (cctx->ctx_skip == SKIP_YES)
7651 	clear_ppconst(&ppconst);
7652     else if (instr->ga_len == instr_count && ppconst.pp_used == 1)
7653     {
7654 	int error = FALSE;
7655 	int v;
7656 
7657 	// The expression results in a constant.
7658 	v = tv_get_bool_chk(&ppconst.pp_tv[0], &error);
7659 	clear_ppconst(&ppconst);
7660 	if (error)
7661 	    return NULL;
7662 	cctx->ctx_skip = v ? SKIP_NOT : SKIP_YES;
7663     }
7664     else
7665     {
7666 	// Not a constant, generate instructions for the expression.
7667 	cctx->ctx_skip = SKIP_UNKNOWN;
7668 	if (generate_ppconst(cctx, &ppconst) == FAIL)
7669 	    return NULL;
7670 	if (bool_on_stack(cctx) == FAIL)
7671 	    return NULL;
7672     }
7673 
7674     // CMDMOD_REV must come before the jump
7675     generate_undo_cmdmods(cctx);
7676 
7677     scope = new_scope(cctx, IF_SCOPE);
7678     if (scope == NULL)
7679 	return NULL;
7680     scope->se_skip_save = skip_save;
7681     // "is_had_return" will be reset if any block does not end in :return
7682     scope->se_u.se_if.is_had_return = TRUE;
7683 
7684     if (cctx->ctx_skip == SKIP_UNKNOWN)
7685     {
7686 	// "where" is set when ":elseif", "else" or ":endif" is found
7687 	scope->se_u.se_if.is_if_label = instr->ga_len;
7688 	generate_JUMP(cctx, JUMP_IF_FALSE, 0);
7689     }
7690     else
7691 	scope->se_u.se_if.is_if_label = -1;
7692 
7693 #ifdef FEAT_PROFILE
7694     if (cctx->ctx_compile_type == CT_PROFILE && cctx->ctx_skip == SKIP_YES
7695 						      && skip_save != SKIP_YES)
7696     {
7697 	// generated a profile start, need to generate a profile end, since it
7698 	// won't be done after returning
7699 	cctx->ctx_skip = SKIP_NOT;
7700 	generate_instr(cctx, ISN_PROF_END);
7701 	cctx->ctx_skip = SKIP_YES;
7702     }
7703 #endif
7704 
7705     return p;
7706 }
7707 
7708     static char_u *
7709 compile_elseif(char_u *arg, cctx_T *cctx)
7710 {
7711     char_u	*p = arg;
7712     garray_T	*instr = &cctx->ctx_instr;
7713     int		instr_count = instr->ga_len;
7714     isn_T	*isn;
7715     scope_T	*scope = cctx->ctx_scope;
7716     ppconst_T	ppconst;
7717     skip_T	save_skip = cctx->ctx_skip;
7718 
7719     if (scope == NULL || scope->se_type != IF_SCOPE)
7720     {
7721 	emsg(_(e_elseif_without_if));
7722 	return NULL;
7723     }
7724     unwind_locals(cctx, scope->se_local_count);
7725     if (!cctx->ctx_had_return)
7726 	scope->se_u.se_if.is_had_return = FALSE;
7727 
7728     if (cctx->ctx_skip == SKIP_NOT)
7729     {
7730 	// previous block was executed, this one and following will not
7731 	cctx->ctx_skip = SKIP_YES;
7732 	scope->se_u.se_if.is_seen_skip_not = TRUE;
7733     }
7734     if (scope->se_u.se_if.is_seen_skip_not)
7735     {
7736 	// A previous block was executed, skip over expression and bail out.
7737 	// Do not count the "elseif" for profiling and cmdmod
7738 	instr->ga_len = current_instr_idx(cctx);
7739 
7740 	skip_expr_cctx(&p, cctx);
7741 	return p;
7742     }
7743 
7744     if (cctx->ctx_skip == SKIP_UNKNOWN)
7745     {
7746 	int	    moved_cmdmod = FALSE;
7747 	int	    saved_debug = FALSE;
7748 	isn_T	    debug_isn;
7749 
7750 	// Move any CMDMOD instruction to after the jump
7751 	if (((isn_T *)instr->ga_data)[instr->ga_len - 1].isn_type == ISN_CMDMOD)
7752 	{
7753 	    if (GA_GROW_FAILS(instr, 1))
7754 		return NULL;
7755 	    ((isn_T *)instr->ga_data)[instr->ga_len] =
7756 				  ((isn_T *)instr->ga_data)[instr->ga_len - 1];
7757 	    --instr->ga_len;
7758 	    moved_cmdmod = TRUE;
7759 	}
7760 
7761 	// Remove the already generated ISN_DEBUG, it is written below the
7762 	// ISN_FOR instruction.
7763 	if (cctx->ctx_compile_type == CT_DEBUG && instr->ga_len > 0
7764 		&& ((isn_T *)instr->ga_data)[instr->ga_len - 1]
7765 							.isn_type == ISN_DEBUG)
7766 	{
7767 	    --instr->ga_len;
7768 	    debug_isn = ((isn_T *)instr->ga_data)[instr->ga_len];
7769 	    saved_debug = TRUE;
7770 	}
7771 
7772 	if (compile_jump_to_end(&scope->se_u.se_if.is_end_label,
7773 						    JUMP_ALWAYS, cctx) == FAIL)
7774 	    return NULL;
7775 	// previous "if" or "elseif" jumps here
7776 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
7777 	isn->isn_arg.jump.jump_where = instr->ga_len;
7778 
7779 	if (moved_cmdmod)
7780 	    ++instr->ga_len;
7781 
7782 	if (saved_debug)
7783 	{
7784 	    // move the debug instruction here
7785 	    if (GA_GROW_FAILS(instr, 1))
7786 		return NULL;
7787 	    ((isn_T *)instr->ga_data)[instr->ga_len] = debug_isn;
7788 	    ++instr->ga_len;
7789 	}
7790     }
7791 
7792     // compile "expr"; if we know it evaluates to FALSE skip the block
7793     CLEAR_FIELD(ppconst);
7794     if (cctx->ctx_skip == SKIP_YES)
7795     {
7796 	cctx->ctx_skip = SKIP_UNKNOWN;
7797 #ifdef FEAT_PROFILE
7798 	if (cctx->ctx_compile_type == CT_PROFILE)
7799 	{
7800 	    // the previous block was skipped, need to profile this line
7801 	    generate_instr(cctx, ISN_PROF_START);
7802 	    instr_count = instr->ga_len;
7803 	}
7804 #endif
7805 	if (cctx->ctx_compile_type == CT_DEBUG)
7806 	{
7807 	    // the previous block was skipped, may want to debug this line
7808 	    generate_instr_debug(cctx);
7809 	    instr_count = instr->ga_len;
7810 	}
7811     }
7812     if (compile_expr1(&p, cctx, &ppconst) == FAIL)
7813     {
7814 	clear_ppconst(&ppconst);
7815 	return NULL;
7816     }
7817     cctx->ctx_skip = save_skip;
7818     if (!ends_excmd2(arg, skipwhite(p)))
7819     {
7820 	semsg(_(e_trailing_arg), p);
7821 	return NULL;
7822     }
7823     if (scope->se_skip_save == SKIP_YES)
7824 	clear_ppconst(&ppconst);
7825     else if (instr->ga_len == instr_count && ppconst.pp_used == 1)
7826     {
7827 	int error = FALSE;
7828 	int v;
7829 
7830 	// The expression results in a constant.
7831 	// TODO: how about nesting?
7832 	v = tv_get_bool_chk(&ppconst.pp_tv[0], &error);
7833 	if (error)
7834 	    return NULL;
7835 	cctx->ctx_skip = v ? SKIP_NOT : SKIP_YES;
7836 	clear_ppconst(&ppconst);
7837 	scope->se_u.se_if.is_if_label = -1;
7838     }
7839     else
7840     {
7841 	// Not a constant, generate instructions for the expression.
7842 	cctx->ctx_skip = SKIP_UNKNOWN;
7843 	if (generate_ppconst(cctx, &ppconst) == FAIL)
7844 	    return NULL;
7845 	if (bool_on_stack(cctx) == FAIL)
7846 	    return NULL;
7847 
7848 	// CMDMOD_REV must come before the jump
7849 	generate_undo_cmdmods(cctx);
7850 
7851 	// "where" is set when ":elseif", "else" or ":endif" is found
7852 	scope->se_u.se_if.is_if_label = instr->ga_len;
7853 	generate_JUMP(cctx, JUMP_IF_FALSE, 0);
7854     }
7855 
7856     return p;
7857 }
7858 
7859     static char_u *
7860 compile_else(char_u *arg, cctx_T *cctx)
7861 {
7862     char_u	*p = arg;
7863     garray_T	*instr = &cctx->ctx_instr;
7864     isn_T	*isn;
7865     scope_T	*scope = cctx->ctx_scope;
7866 
7867     if (scope == NULL || scope->se_type != IF_SCOPE)
7868     {
7869 	emsg(_(e_else_without_if));
7870 	return NULL;
7871     }
7872     unwind_locals(cctx, scope->se_local_count);
7873     if (!cctx->ctx_had_return)
7874 	scope->se_u.se_if.is_had_return = FALSE;
7875     scope->se_u.se_if.is_seen_else = TRUE;
7876 
7877 #ifdef FEAT_PROFILE
7878     if (cctx->ctx_compile_type == CT_PROFILE)
7879     {
7880 	if (cctx->ctx_skip == SKIP_NOT
7881 		&& ((isn_T *)instr->ga_data)[instr->ga_len - 1]
7882 						   .isn_type == ISN_PROF_START)
7883 	    // the previous block was executed, do not count "else" for
7884 	    // profiling
7885 	    --instr->ga_len;
7886 	if (cctx->ctx_skip == SKIP_YES && !scope->se_u.se_if.is_seen_skip_not)
7887 	{
7888 	    // the previous block was not executed, this one will, do count the
7889 	    // "else" for profiling
7890 	    cctx->ctx_skip = SKIP_NOT;
7891 	    generate_instr(cctx, ISN_PROF_END);
7892 	    generate_instr(cctx, ISN_PROF_START);
7893 	    cctx->ctx_skip = SKIP_YES;
7894 	}
7895     }
7896 #endif
7897 
7898     if (!scope->se_u.se_if.is_seen_skip_not && scope->se_skip_save != SKIP_YES)
7899     {
7900 	// jump from previous block to the end, unless the else block is empty
7901 	if (cctx->ctx_skip == SKIP_UNKNOWN)
7902 	{
7903 	    if (!cctx->ctx_had_return
7904 		    && compile_jump_to_end(&scope->se_u.se_if.is_end_label,
7905 						    JUMP_ALWAYS, cctx) == FAIL)
7906 		return NULL;
7907 	}
7908 
7909 	if (cctx->ctx_skip == SKIP_UNKNOWN)
7910 	{
7911 	    if (scope->se_u.se_if.is_if_label >= 0)
7912 	    {
7913 		// previous "if" or "elseif" jumps here
7914 		isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
7915 		isn->isn_arg.jump.jump_where = instr->ga_len;
7916 		scope->se_u.se_if.is_if_label = -1;
7917 	    }
7918 	}
7919 
7920 	if (cctx->ctx_skip != SKIP_UNKNOWN)
7921 	    cctx->ctx_skip = cctx->ctx_skip == SKIP_YES ? SKIP_NOT : SKIP_YES;
7922     }
7923 
7924     return p;
7925 }
7926 
7927     static char_u *
7928 compile_endif(char_u *arg, cctx_T *cctx)
7929 {
7930     scope_T	*scope = cctx->ctx_scope;
7931     ifscope_T	*ifscope;
7932     garray_T	*instr = &cctx->ctx_instr;
7933     isn_T	*isn;
7934 
7935     if (misplaced_cmdmod(cctx))
7936 	return NULL;
7937 
7938     if (scope == NULL || scope->se_type != IF_SCOPE)
7939     {
7940 	emsg(_(e_endif_without_if));
7941 	return NULL;
7942     }
7943     ifscope = &scope->se_u.se_if;
7944     unwind_locals(cctx, scope->se_local_count);
7945     if (!cctx->ctx_had_return)
7946 	ifscope->is_had_return = FALSE;
7947 
7948     if (scope->se_u.se_if.is_if_label >= 0)
7949     {
7950 	// previous "if" or "elseif" jumps here
7951 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
7952 	isn->isn_arg.jump.jump_where = instr->ga_len;
7953     }
7954     // Fill in the "end" label in jumps at the end of the blocks.
7955     compile_fill_jump_to_end(&ifscope->is_end_label, instr->ga_len, cctx);
7956 
7957 #ifdef FEAT_PROFILE
7958     // even when skipping we count the endif as executed, unless the block it's
7959     // in is skipped
7960     if (cctx->ctx_compile_type == CT_PROFILE && cctx->ctx_skip == SKIP_YES
7961 					    && scope->se_skip_save != SKIP_YES)
7962     {
7963 	cctx->ctx_skip = SKIP_NOT;
7964 	generate_instr(cctx, ISN_PROF_START);
7965     }
7966 #endif
7967     cctx->ctx_skip = scope->se_skip_save;
7968 
7969     // If all the blocks end in :return and there is an :else then the
7970     // had_return flag is set.
7971     cctx->ctx_had_return = ifscope->is_had_return && ifscope->is_seen_else;
7972 
7973     drop_scope(cctx);
7974     return arg;
7975 }
7976 
7977 /*
7978  * Compile "for var in expr":
7979  *
7980  * Produces instructions:
7981  *       PUSHNR -1
7982  *       STORE loop-idx		Set index to -1
7983  *       EVAL expr		result of "expr" on top of stack
7984  * top:  FOR loop-idx, end	Increment index, use list on bottom of stack
7985  *				- if beyond end, jump to "end"
7986  *				- otherwise get item from list and push it
7987  *       STORE var		Store item in "var"
7988  *       ... body ...
7989  *       JUMP top		Jump back to repeat
7990  * end:	 DROP			Drop the result of "expr"
7991  *
7992  * Compile "for [var1, var2] in expr" - as above, but instead of "STORE var":
7993  *	 UNPACK 2		Split item in 2
7994  *       STORE var1		Store item in "var1"
7995  *       STORE var2		Store item in "var2"
7996  */
7997     static char_u *
7998 compile_for(char_u *arg_start, cctx_T *cctx)
7999 {
8000     char_u	*arg;
8001     char_u	*arg_end;
8002     char_u	*name = NULL;
8003     char_u	*p;
8004     char_u	*wp;
8005     int		var_count = 0;
8006     int		var_list = FALSE;
8007     int		semicolon = FALSE;
8008     size_t	varlen;
8009     garray_T	*stack = &cctx->ctx_type_stack;
8010     garray_T	*instr = &cctx->ctx_instr;
8011     scope_T	*scope;
8012     lvar_T	*loop_lvar;	// loop iteration variable
8013     lvar_T	*var_lvar;	// variable for "var"
8014     type_T	*vartype;
8015     type_T	*item_type = &t_any;
8016     int		idx;
8017     int		prev_lnum = cctx->ctx_prev_lnum;
8018 
8019     p = skip_var_list(arg_start, TRUE, &var_count, &semicolon, FALSE);
8020     if (p == NULL)
8021 	return NULL;
8022     if (var_count == 0)
8023 	var_count = 1;
8024     else
8025 	var_list = TRUE;  // can also be a list of one variable
8026 
8027     // consume "in"
8028     wp = p;
8029     if (may_get_next_line_error(wp, &p, cctx) == FAIL)
8030 	return NULL;
8031     if (STRNCMP(p, "in", 2) != 0 || !IS_WHITE_OR_NUL(p[2]))
8032     {
8033 	if (*p == ':' && wp != p)
8034 	    semsg(_(e_no_white_space_allowed_before_colon_str), p);
8035 	else
8036 	    emsg(_(e_missing_in));
8037 	return NULL;
8038     }
8039     wp = p + 2;
8040     if (may_get_next_line_error(wp, &p, cctx) == FAIL)
8041 	return NULL;
8042 
8043     // Remove the already generated ISN_DEBUG, it is written below the ISN_FOR
8044     // instruction.
8045     if (cctx->ctx_compile_type == CT_DEBUG && instr->ga_len > 0
8046 	    && ((isn_T *)instr->ga_data)[instr->ga_len - 1]
8047 							.isn_type == ISN_DEBUG)
8048     {
8049 	--instr->ga_len;
8050 	prev_lnum = ((isn_T *)instr->ga_data)[instr->ga_len]
8051 						 .isn_arg.debug.dbg_break_lnum;
8052     }
8053 
8054     scope = new_scope(cctx, FOR_SCOPE);
8055     if (scope == NULL)
8056 	return NULL;
8057 
8058     // Reserve a variable to store the loop iteration counter and initialize it
8059     // to -1.
8060     loop_lvar = reserve_local(cctx, (char_u *)"", 0, FALSE, &t_number);
8061     if (loop_lvar == NULL)
8062     {
8063 	// out of memory
8064 	drop_scope(cctx);
8065 	return NULL;
8066     }
8067     generate_STORENR(cctx, loop_lvar->lv_idx, -1);
8068 
8069     // compile "expr", it remains on the stack until "endfor"
8070     arg = p;
8071     if (compile_expr0(&arg, cctx) == FAIL)
8072     {
8073 	drop_scope(cctx);
8074 	return NULL;
8075     }
8076     arg_end = arg;
8077 
8078     if (cctx->ctx_skip != SKIP_YES)
8079     {
8080 	// If we know the type of "var" and it is a not a supported type we can
8081 	// give an error now.
8082 	vartype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
8083 	if (vartype->tt_type != VAR_LIST && vartype->tt_type != VAR_STRING
8084 		&& vartype->tt_type != VAR_BLOB && vartype->tt_type != VAR_ANY)
8085 	{
8086 	    semsg(_(e_for_loop_on_str_not_supported),
8087 					       vartype_name(vartype->tt_type));
8088 	    drop_scope(cctx);
8089 	    return NULL;
8090 	}
8091 
8092 	if (vartype->tt_type == VAR_STRING)
8093 	    item_type = &t_string;
8094 	else if (vartype->tt_type == VAR_BLOB)
8095 	    item_type = &t_number;
8096 	else if (vartype->tt_type == VAR_LIST
8097 				     && vartype->tt_member->tt_type != VAR_ANY)
8098 	{
8099 	    if (!var_list)
8100 		item_type = vartype->tt_member;
8101 	    else if (vartype->tt_member->tt_type == VAR_LIST
8102 			  && vartype->tt_member->tt_member->tt_type != VAR_ANY)
8103 		// TODO: should get the type for each lhs
8104 		item_type = vartype->tt_member->tt_member;
8105 	}
8106 
8107 	// CMDMOD_REV must come before the FOR instruction.
8108 	generate_undo_cmdmods(cctx);
8109 
8110 	// "for_end" is set when ":endfor" is found
8111 	scope->se_u.se_for.fs_top_label = current_instr_idx(cctx);
8112 
8113 	generate_FOR(cctx, loop_lvar->lv_idx);
8114 
8115 	arg = arg_start;
8116 	if (var_list)
8117 	{
8118 	    generate_UNPACK(cctx, var_count, semicolon);
8119 	    arg = skipwhite(arg + 1);	// skip white after '['
8120 
8121 	    // the list item is replaced by a number of items
8122 	    if (GA_GROW_FAILS(stack, var_count - 1))
8123 	    {
8124 		drop_scope(cctx);
8125 		return NULL;
8126 	    }
8127 	    --stack->ga_len;
8128 	    for (idx = 0; idx < var_count; ++idx)
8129 	    {
8130 		((type_T **)stack->ga_data)[stack->ga_len] =
8131 				 (semicolon && idx == 0) ? vartype : item_type;
8132 		++stack->ga_len;
8133 	    }
8134 	}
8135 
8136 	for (idx = 0; idx < var_count; ++idx)
8137 	{
8138 	    assign_dest_T	dest = dest_local;
8139 	    int		opt_flags = 0;
8140 	    int		vimvaridx = -1;
8141 	    type_T		*type = &t_any;
8142 	    type_T		*lhs_type = &t_any;
8143 	    where_T		where = WHERE_INIT;
8144 
8145 	    p = skip_var_one(arg, FALSE);
8146 	    varlen = p - arg;
8147 	    name = vim_strnsave(arg, varlen);
8148 	    if (name == NULL)
8149 		goto failed;
8150 	    if (*p == ':')
8151 	    {
8152 		p = skipwhite(p + 1);
8153 		lhs_type = parse_type(&p, cctx->ctx_type_list, TRUE);
8154 	    }
8155 
8156 	    // TODO: script var not supported?
8157 	    if (get_var_dest(name, &dest, CMD_for, &opt_flags,
8158 					      &vimvaridx, &type, cctx) == FAIL)
8159 		goto failed;
8160 	    if (dest != dest_local)
8161 	    {
8162 		if (generate_store_var(cctx, dest, opt_flags, vimvaridx,
8163 						     0, 0, type, name) == FAIL)
8164 		    goto failed;
8165 	    }
8166 	    else if (varlen == 1 && *arg == '_')
8167 	    {
8168 		// Assigning to "_": drop the value.
8169 		if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
8170 		    goto failed;
8171 	    }
8172 	    else
8173 	    {
8174 		if (lookup_local(arg, varlen, NULL, cctx) == OK)
8175 		{
8176 		    semsg(_(e_variable_already_declared), arg);
8177 		    goto failed;
8178 		}
8179 
8180 		if (STRNCMP(name, "s:", 2) == 0)
8181 		{
8182 		    semsg(_(e_cannot_declare_script_variable_in_function), name);
8183 		    goto failed;
8184 		}
8185 
8186 		// Reserve a variable to store "var".
8187 		where.wt_index = var_list ? idx + 1 : 0;
8188 		where.wt_variable = TRUE;
8189 		if (lhs_type == &t_any)
8190 		    lhs_type = item_type;
8191 		else if (item_type != &t_unknown
8192 			    && (item_type == &t_any
8193 			      ? need_type(item_type, lhs_type,
8194 						     -1, 0, cctx, FALSE, FALSE)
8195 			      : check_type(lhs_type, item_type, TRUE, where))
8196 			    == FAIL)
8197 		    goto failed;
8198 		var_lvar = reserve_local(cctx, arg, varlen, TRUE, lhs_type);
8199 		if (var_lvar == NULL)
8200 		    // out of memory or used as an argument
8201 		    goto failed;
8202 
8203 		if (semicolon && idx == var_count - 1)
8204 		    var_lvar->lv_type = vartype;
8205 		else
8206 		    var_lvar->lv_type = item_type;
8207 		generate_STORE(cctx, ISN_STORE, var_lvar->lv_idx, NULL);
8208 	    }
8209 
8210 	    if (*p == ',' || *p == ';')
8211 		++p;
8212 	    arg = skipwhite(p);
8213 	    vim_free(name);
8214 	}
8215 
8216 	if (cctx->ctx_compile_type == CT_DEBUG)
8217 	{
8218 	    int save_prev_lnum = cctx->ctx_prev_lnum;
8219 
8220 	    // Add ISN_DEBUG here, so that the loop variables can be inspected.
8221 	    // Use the prev_lnum from the ISN_DEBUG instruction removed above.
8222 	    cctx->ctx_prev_lnum = prev_lnum;
8223 	    generate_instr_debug(cctx);
8224 	    cctx->ctx_prev_lnum = save_prev_lnum;
8225 	}
8226     }
8227 
8228     return arg_end;
8229 
8230 failed:
8231     vim_free(name);
8232     drop_scope(cctx);
8233     return NULL;
8234 }
8235 
8236 /*
8237  * compile "endfor"
8238  */
8239     static char_u *
8240 compile_endfor(char_u *arg, cctx_T *cctx)
8241 {
8242     garray_T	*instr = &cctx->ctx_instr;
8243     scope_T	*scope = cctx->ctx_scope;
8244     forscope_T	*forscope;
8245     isn_T	*isn;
8246 
8247     if (misplaced_cmdmod(cctx))
8248 	return NULL;
8249 
8250     if (scope == NULL || scope->se_type != FOR_SCOPE)
8251     {
8252 	emsg(_(e_for));
8253 	return NULL;
8254     }
8255     forscope = &scope->se_u.se_for;
8256     cctx->ctx_scope = scope->se_outer;
8257     if (cctx->ctx_skip != SKIP_YES)
8258     {
8259 	unwind_locals(cctx, scope->se_local_count);
8260 
8261 	// At end of ":for" scope jump back to the FOR instruction.
8262 	generate_JUMP(cctx, JUMP_ALWAYS, forscope->fs_top_label);
8263 
8264 	// Fill in the "end" label in the FOR statement so it can jump here.
8265 	isn = ((isn_T *)instr->ga_data) + forscope->fs_top_label;
8266 	isn->isn_arg.forloop.for_end = instr->ga_len;
8267 
8268 	// Fill in the "end" label any BREAK statements
8269 	compile_fill_jump_to_end(&forscope->fs_end_label, instr->ga_len, cctx);
8270 
8271 	// Below the ":for" scope drop the "expr" list from the stack.
8272 	if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
8273 	    return NULL;
8274     }
8275 
8276     vim_free(scope);
8277 
8278     return arg;
8279 }
8280 
8281 /*
8282  * compile "while expr"
8283  *
8284  * Produces instructions:
8285  * top:  EVAL expr		Push result of "expr"
8286  *       JUMP_IF_FALSE end	jump if false
8287  *       ... body ...
8288  *       JUMP top		Jump back to repeat
8289  * end:
8290  *
8291  */
8292     static char_u *
8293 compile_while(char_u *arg, cctx_T *cctx)
8294 {
8295     char_u	*p = arg;
8296     scope_T	*scope;
8297 
8298     scope = new_scope(cctx, WHILE_SCOPE);
8299     if (scope == NULL)
8300 	return NULL;
8301 
8302     // "endwhile" jumps back here, one before when profiling or using cmdmods
8303     scope->se_u.se_while.ws_top_label = current_instr_idx(cctx);
8304 
8305     // compile "expr"
8306     if (compile_expr0(&p, cctx) == FAIL)
8307 	return NULL;
8308 
8309     if (!ends_excmd2(arg, skipwhite(p)))
8310     {
8311 	semsg(_(e_trailing_arg), p);
8312 	return NULL;
8313     }
8314 
8315     if (cctx->ctx_skip != SKIP_YES)
8316     {
8317 	if (bool_on_stack(cctx) == FAIL)
8318 	    return FAIL;
8319 
8320 	// CMDMOD_REV must come before the jump
8321 	generate_undo_cmdmods(cctx);
8322 
8323 	// "while_end" is set when ":endwhile" is found
8324 	if (compile_jump_to_end(&scope->se_u.se_while.ws_end_label,
8325 						  JUMP_IF_FALSE, cctx) == FAIL)
8326 	    return FAIL;
8327     }
8328 
8329     return p;
8330 }
8331 
8332 /*
8333  * compile "endwhile"
8334  */
8335     static char_u *
8336 compile_endwhile(char_u *arg, cctx_T *cctx)
8337 {
8338     scope_T	*scope = cctx->ctx_scope;
8339     garray_T	*instr = &cctx->ctx_instr;
8340 
8341     if (misplaced_cmdmod(cctx))
8342 	return NULL;
8343     if (scope == NULL || scope->se_type != WHILE_SCOPE)
8344     {
8345 	emsg(_(e_while));
8346 	return NULL;
8347     }
8348     cctx->ctx_scope = scope->se_outer;
8349     if (cctx->ctx_skip != SKIP_YES)
8350     {
8351 	unwind_locals(cctx, scope->se_local_count);
8352 
8353 #ifdef FEAT_PROFILE
8354 	// count the endwhile before jumping
8355 	may_generate_prof_end(cctx, cctx->ctx_lnum);
8356 #endif
8357 
8358 	// At end of ":for" scope jump back to the FOR instruction.
8359 	generate_JUMP(cctx, JUMP_ALWAYS, scope->se_u.se_while.ws_top_label);
8360 
8361 	// Fill in the "end" label in the WHILE statement so it can jump here.
8362 	// And in any jumps for ":break"
8363 	compile_fill_jump_to_end(&scope->se_u.se_while.ws_end_label,
8364 							  instr->ga_len, cctx);
8365     }
8366 
8367     vim_free(scope);
8368 
8369     return arg;
8370 }
8371 
8372 /*
8373  * compile "continue"
8374  */
8375     static char_u *
8376 compile_continue(char_u *arg, cctx_T *cctx)
8377 {
8378     scope_T	*scope = cctx->ctx_scope;
8379     int		try_scopes = 0;
8380     int		loop_label;
8381 
8382     for (;;)
8383     {
8384 	if (scope == NULL)
8385 	{
8386 	    emsg(_(e_continue));
8387 	    return NULL;
8388 	}
8389 	if (scope->se_type == FOR_SCOPE)
8390 	{
8391 	    loop_label = scope->se_u.se_for.fs_top_label;
8392 	    break;
8393 	}
8394 	if (scope->se_type == WHILE_SCOPE)
8395 	{
8396 	    loop_label = scope->se_u.se_while.ws_top_label;
8397 	    break;
8398 	}
8399 	if (scope->se_type == TRY_SCOPE)
8400 	    ++try_scopes;
8401 	scope = scope->se_outer;
8402     }
8403 
8404     if (try_scopes > 0)
8405 	// Inside one or more try/catch blocks we first need to jump to the
8406 	// "finally" or "endtry" to cleanup.
8407 	generate_TRYCONT(cctx, try_scopes, loop_label);
8408     else
8409 	// Jump back to the FOR or WHILE instruction.
8410 	generate_JUMP(cctx, JUMP_ALWAYS, loop_label);
8411 
8412     return arg;
8413 }
8414 
8415 /*
8416  * compile "break"
8417  */
8418     static char_u *
8419 compile_break(char_u *arg, cctx_T *cctx)
8420 {
8421     scope_T	*scope = cctx->ctx_scope;
8422     endlabel_T	**el;
8423 
8424     for (;;)
8425     {
8426 	if (scope == NULL)
8427 	{
8428 	    emsg(_(e_break));
8429 	    return NULL;
8430 	}
8431 	if (scope->se_type == FOR_SCOPE || scope->se_type == WHILE_SCOPE)
8432 	    break;
8433 	scope = scope->se_outer;
8434     }
8435 
8436     // Jump to the end of the FOR or WHILE loop.
8437     if (scope->se_type == FOR_SCOPE)
8438 	el = &scope->se_u.se_for.fs_end_label;
8439     else
8440 	el = &scope->se_u.se_while.ws_end_label;
8441     if (compile_jump_to_end(el, JUMP_ALWAYS, cctx) == FAIL)
8442 	return FAIL;
8443 
8444     return arg;
8445 }
8446 
8447 /*
8448  * compile "{" start of block
8449  */
8450     static char_u *
8451 compile_block(char_u *arg, cctx_T *cctx)
8452 {
8453     if (new_scope(cctx, BLOCK_SCOPE) == NULL)
8454 	return NULL;
8455     return skipwhite(arg + 1);
8456 }
8457 
8458 /*
8459  * compile end of block: drop one scope
8460  */
8461     static void
8462 compile_endblock(cctx_T *cctx)
8463 {
8464     scope_T	*scope = cctx->ctx_scope;
8465 
8466     cctx->ctx_scope = scope->se_outer;
8467     unwind_locals(cctx, scope->se_local_count);
8468     vim_free(scope);
8469 }
8470 
8471 /*
8472  * compile "try"
8473  * Creates a new scope for the try-endtry, pointing to the first catch and
8474  * finally.
8475  * Creates another scope for the "try" block itself.
8476  * TRY instruction sets up exception handling at runtime.
8477  *
8478  *	"try"
8479  *	    TRY -> catch1, -> finally  push trystack entry
8480  *	    ... try block
8481  *	"throw {exception}"
8482  *	    EVAL {exception}
8483  *	    THROW		create exception
8484  *	    ... try block
8485  *	" catch {expr}"
8486  *	    JUMP -> finally
8487  * catch1:  PUSH exception
8488  *	    EVAL {expr}
8489  *	    MATCH
8490  *	    JUMP nomatch -> catch2
8491  *	    CATCH   remove exception
8492  *	    ... catch block
8493  *	" catch"
8494  *	    JUMP -> finally
8495  * catch2:  CATCH   remove exception
8496  *	    ... catch block
8497  *	" finally"
8498  * finally:
8499  *	    ... finally block
8500  *	" endtry"
8501  *	    ENDTRY  pop trystack entry, may rethrow
8502  */
8503     static char_u *
8504 compile_try(char_u *arg, cctx_T *cctx)
8505 {
8506     garray_T	*instr = &cctx->ctx_instr;
8507     scope_T	*try_scope;
8508     scope_T	*scope;
8509 
8510     if (misplaced_cmdmod(cctx))
8511 	return NULL;
8512 
8513     // scope that holds the jumps that go to catch/finally/endtry
8514     try_scope = new_scope(cctx, TRY_SCOPE);
8515     if (try_scope == NULL)
8516 	return NULL;
8517 
8518     if (cctx->ctx_skip != SKIP_YES)
8519     {
8520 	isn_T	*isn;
8521 
8522 	// "try_catch" is set when the first ":catch" is found or when no catch
8523 	// is found and ":finally" is found.
8524 	// "try_finally" is set when ":finally" is found
8525 	// "try_endtry" is set when ":endtry" is found
8526 	try_scope->se_u.se_try.ts_try_label = instr->ga_len;
8527 	if ((isn = generate_instr(cctx, ISN_TRY)) == NULL)
8528 	    return NULL;
8529 	isn->isn_arg.try.try_ref = ALLOC_CLEAR_ONE(tryref_T);
8530 	if (isn->isn_arg.try.try_ref == NULL)
8531 	    return NULL;
8532     }
8533 
8534     // scope for the try block itself
8535     scope = new_scope(cctx, BLOCK_SCOPE);
8536     if (scope == NULL)
8537 	return NULL;
8538 
8539     return arg;
8540 }
8541 
8542 /*
8543  * compile "catch {expr}"
8544  */
8545     static char_u *
8546 compile_catch(char_u *arg, cctx_T *cctx UNUSED)
8547 {
8548     scope_T	*scope = cctx->ctx_scope;
8549     garray_T	*instr = &cctx->ctx_instr;
8550     char_u	*p;
8551     isn_T	*isn;
8552 
8553     if (misplaced_cmdmod(cctx))
8554 	return NULL;
8555 
8556     // end block scope from :try or :catch
8557     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
8558 	compile_endblock(cctx);
8559     scope = cctx->ctx_scope;
8560 
8561     // Error if not in a :try scope
8562     if (scope == NULL || scope->se_type != TRY_SCOPE)
8563     {
8564 	emsg(_(e_catch));
8565 	return NULL;
8566     }
8567 
8568     if (scope->se_u.se_try.ts_caught_all)
8569     {
8570 	emsg(_(e_catch_unreachable_after_catch_all));
8571 	return NULL;
8572     }
8573 
8574     if (cctx->ctx_skip != SKIP_YES)
8575     {
8576 #ifdef FEAT_PROFILE
8577 	// the profile-start should be after the jump
8578 	if (cctx->ctx_compile_type == CT_PROFILE
8579 		&& instr->ga_len > 0
8580 		&& ((isn_T *)instr->ga_data)[instr->ga_len - 1]
8581 						   .isn_type == ISN_PROF_START)
8582 	    --instr->ga_len;
8583 #endif
8584 	// Jump from end of previous block to :finally or :endtry
8585 	if (compile_jump_to_end(&scope->se_u.se_try.ts_end_label,
8586 						    JUMP_ALWAYS, cctx) == FAIL)
8587 	    return NULL;
8588 
8589 	// End :try or :catch scope: set value in ISN_TRY instruction
8590 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
8591 	if (isn->isn_arg.try.try_ref->try_catch == 0)
8592 	    isn->isn_arg.try.try_ref->try_catch = instr->ga_len;
8593 	if (scope->se_u.se_try.ts_catch_label != 0)
8594 	{
8595 	    // Previous catch without match jumps here
8596 	    isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_catch_label;
8597 	    isn->isn_arg.jump.jump_where = instr->ga_len;
8598 	}
8599 #ifdef FEAT_PROFILE
8600 	if (cctx->ctx_compile_type == CT_PROFILE)
8601 	{
8602 	    // a "throw" that jumps here needs to be counted
8603 	    generate_instr(cctx, ISN_PROF_END);
8604 	    // the "catch" is also counted
8605 	    generate_instr(cctx, ISN_PROF_START);
8606 	}
8607 #endif
8608 	if (cctx->ctx_compile_type == CT_DEBUG)
8609 	    generate_instr_debug(cctx);
8610     }
8611 
8612     p = skipwhite(arg);
8613     if (ends_excmd2(arg, p))
8614     {
8615 	scope->se_u.se_try.ts_caught_all = TRUE;
8616 	scope->se_u.se_try.ts_catch_label = 0;
8617     }
8618     else
8619     {
8620 	char_u *end;
8621 	char_u *pat;
8622 	char_u *tofree = NULL;
8623 	int	dropped = 0;
8624 	int	len;
8625 
8626 	// Push v:exception, push {expr} and MATCH
8627 	generate_instr_type(cctx, ISN_PUSHEXC, &t_string);
8628 
8629 	end = skip_regexp_ex(p + 1, *p, TRUE, &tofree, &dropped, NULL);
8630 	if (*end != *p)
8631 	{
8632 	    semsg(_(e_separator_mismatch_str), p);
8633 	    vim_free(tofree);
8634 	    return FAIL;
8635 	}
8636 	if (tofree == NULL)
8637 	    len = (int)(end - (p + 1));
8638 	else
8639 	    len = (int)(end - tofree);
8640 	pat = vim_strnsave(tofree == NULL ? p + 1 : tofree, len);
8641 	vim_free(tofree);
8642 	p += len + 2 + dropped;
8643 	if (pat == NULL)
8644 	    return FAIL;
8645 	if (generate_PUSHS(cctx, &pat) == FAIL)
8646 	    return FAIL;
8647 
8648 	if (generate_COMPARE(cctx, EXPR_MATCH, FALSE) == FAIL)
8649 	    return NULL;
8650 
8651 	scope->se_u.se_try.ts_catch_label = instr->ga_len;
8652 	if (generate_JUMP(cctx, JUMP_IF_FALSE, 0) == FAIL)
8653 	    return NULL;
8654     }
8655 
8656     if (cctx->ctx_skip != SKIP_YES && generate_instr(cctx, ISN_CATCH) == NULL)
8657 	return NULL;
8658 
8659     if (new_scope(cctx, BLOCK_SCOPE) == NULL)
8660 	return NULL;
8661     return p;
8662 }
8663 
8664     static char_u *
8665 compile_finally(char_u *arg, cctx_T *cctx)
8666 {
8667     scope_T	*scope = cctx->ctx_scope;
8668     garray_T	*instr = &cctx->ctx_instr;
8669     isn_T	*isn;
8670     int		this_instr;
8671 
8672     if (misplaced_cmdmod(cctx))
8673 	return NULL;
8674 
8675     // end block scope from :try or :catch
8676     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
8677 	compile_endblock(cctx);
8678     scope = cctx->ctx_scope;
8679 
8680     // Error if not in a :try scope
8681     if (scope == NULL || scope->se_type != TRY_SCOPE)
8682     {
8683 	emsg(_(e_finally));
8684 	return NULL;
8685     }
8686 
8687     if (cctx->ctx_skip != SKIP_YES)
8688     {
8689 	// End :catch or :finally scope: set value in ISN_TRY instruction
8690 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
8691 	if (isn->isn_arg.try.try_ref->try_finally != 0)
8692 	{
8693 	    emsg(_(e_finally_dup));
8694 	    return NULL;
8695 	}
8696 
8697 	this_instr = instr->ga_len;
8698 #ifdef FEAT_PROFILE
8699 	if (cctx->ctx_compile_type == CT_PROFILE
8700 		&& ((isn_T *)instr->ga_data)[this_instr - 1]
8701 						       .isn_type == ISN_PROF_START)
8702 	{
8703 	    // jump to the profile start of the "finally"
8704 	    --this_instr;
8705 
8706 	    // jump to the profile end above it
8707 	    if (this_instr > 0 && ((isn_T *)instr->ga_data)[this_instr - 1]
8708 							 .isn_type == ISN_PROF_END)
8709 		--this_instr;
8710 	}
8711 #endif
8712 
8713 	// Fill in the "end" label in jumps at the end of the blocks.
8714 	compile_fill_jump_to_end(&scope->se_u.se_try.ts_end_label,
8715 								this_instr, cctx);
8716 
8717 	// If there is no :catch then an exception jumps to :finally.
8718 	if (isn->isn_arg.try.try_ref->try_catch == 0)
8719 	    isn->isn_arg.try.try_ref->try_catch = this_instr;
8720 	isn->isn_arg.try.try_ref->try_finally = this_instr;
8721 	if (scope->se_u.se_try.ts_catch_label != 0)
8722 	{
8723 	    // Previous catch without match jumps here
8724 	    isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_catch_label;
8725 	    isn->isn_arg.jump.jump_where = this_instr;
8726 	    scope->se_u.se_try.ts_catch_label = 0;
8727 	}
8728 	if (generate_instr(cctx, ISN_FINALLY) == NULL)
8729 	    return NULL;
8730 
8731 	// TODO: set index in ts_finally_label jumps
8732     }
8733 
8734     return arg;
8735 }
8736 
8737     static char_u *
8738 compile_endtry(char_u *arg, cctx_T *cctx)
8739 {
8740     scope_T	*scope = cctx->ctx_scope;
8741     garray_T	*instr = &cctx->ctx_instr;
8742     isn_T	*try_isn;
8743 
8744     if (misplaced_cmdmod(cctx))
8745 	return NULL;
8746 
8747     // end block scope from :catch or :finally
8748     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
8749 	compile_endblock(cctx);
8750     scope = cctx->ctx_scope;
8751 
8752     // Error if not in a :try scope
8753     if (scope == NULL || scope->se_type != TRY_SCOPE)
8754     {
8755 	if (scope == NULL)
8756 	    emsg(_(e_no_endtry));
8757 	else if (scope->se_type == WHILE_SCOPE)
8758 	    emsg(_(e_endwhile));
8759 	else if (scope->se_type == FOR_SCOPE)
8760 	    emsg(_(e_endfor));
8761 	else
8762 	    emsg(_(e_endif));
8763 	return NULL;
8764     }
8765 
8766     try_isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
8767     if (cctx->ctx_skip != SKIP_YES)
8768     {
8769 	if (try_isn->isn_arg.try.try_ref->try_catch == 0
8770 				      && try_isn->isn_arg.try.try_ref->try_finally == 0)
8771 	{
8772 	    emsg(_(e_missing_catch_or_finally));
8773 	    return NULL;
8774 	}
8775 
8776 #ifdef FEAT_PROFILE
8777 	if (cctx->ctx_compile_type == CT_PROFILE
8778 		&& ((isn_T *)instr->ga_data)[instr->ga_len - 1]
8779 						.isn_type == ISN_PROF_START)
8780 	    // move the profile start after "endtry" so that it's not counted when
8781 	    // the exception is rethrown.
8782 	    --instr->ga_len;
8783 #endif
8784 
8785 	// Fill in the "end" label in jumps at the end of the blocks, if not
8786 	// done by ":finally".
8787 	compile_fill_jump_to_end(&scope->se_u.se_try.ts_end_label,
8788 							  instr->ga_len, cctx);
8789 
8790 	if (scope->se_u.se_try.ts_catch_label != 0)
8791 	{
8792 	    // Last catch without match jumps here
8793 	    isn_T *isn = ((isn_T *)instr->ga_data)
8794 					   + scope->se_u.se_try.ts_catch_label;
8795 	    isn->isn_arg.jump.jump_where = instr->ga_len;
8796 	}
8797     }
8798 
8799     compile_endblock(cctx);
8800 
8801     if (cctx->ctx_skip != SKIP_YES)
8802     {
8803 	// End :catch or :finally scope: set instruction index in ISN_TRY
8804 	// instruction
8805 	try_isn->isn_arg.try.try_ref->try_endtry = instr->ga_len;
8806 	if (cctx->ctx_skip != SKIP_YES
8807 				   && generate_instr(cctx, ISN_ENDTRY) == NULL)
8808 	    return NULL;
8809 #ifdef FEAT_PROFILE
8810 	if (cctx->ctx_compile_type == CT_PROFILE)
8811 	    generate_instr(cctx, ISN_PROF_START);
8812 #endif
8813     }
8814     return arg;
8815 }
8816 
8817 /*
8818  * compile "throw {expr}"
8819  */
8820     static char_u *
8821 compile_throw(char_u *arg, cctx_T *cctx UNUSED)
8822 {
8823     char_u *p = skipwhite(arg);
8824 
8825     if (compile_expr0(&p, cctx) == FAIL)
8826 	return NULL;
8827     if (cctx->ctx_skip == SKIP_YES)
8828 	return p;
8829     if (may_generate_2STRING(-1, FALSE, cctx) == FAIL)
8830 	return NULL;
8831     if (generate_instr_drop(cctx, ISN_THROW, 1) == NULL)
8832 	return NULL;
8833 
8834     return p;
8835 }
8836 
8837     static char_u *
8838 compile_eval(char_u *arg, cctx_T *cctx)
8839 {
8840     char_u	*p = arg;
8841     int		name_only;
8842     long	lnum = SOURCING_LNUM;
8843 
8844     // find_ex_command() will consider a variable name an expression, assuming
8845     // that something follows on the next line.  Check that something actually
8846     // follows, otherwise it's probably a misplaced command.
8847     name_only = cmd_is_name_only(arg);
8848 
8849     if (compile_expr0(&p, cctx) == FAIL)
8850 	return NULL;
8851 
8852     if (name_only && lnum == SOURCING_LNUM)
8853     {
8854 	semsg(_(e_expression_without_effect_str), arg);
8855 	return NULL;
8856     }
8857 
8858     // drop the result
8859     generate_instr_drop(cctx, ISN_DROP, 1);
8860 
8861     return skipwhite(p);
8862 }
8863 
8864 /*
8865  * compile "echo expr"
8866  * compile "echomsg expr"
8867  * compile "echoerr expr"
8868  * compile "echoconsole expr"
8869  * compile "execute expr"
8870  */
8871     static char_u *
8872 compile_mult_expr(char_u *arg, int cmdidx, cctx_T *cctx)
8873 {
8874     char_u	*p = arg;
8875     char_u	*prev = arg;
8876     char_u	*expr_start;
8877     int		count = 0;
8878     int		start_ctx_lnum = cctx->ctx_lnum;
8879     garray_T	*stack = &cctx->ctx_type_stack;
8880     type_T	*type;
8881 
8882     for (;;)
8883     {
8884 	if (ends_excmd2(prev, p))
8885 	    break;
8886 	expr_start = p;
8887 	if (compile_expr0(&p, cctx) == FAIL)
8888 	    return NULL;
8889 
8890 	if (cctx->ctx_skip != SKIP_YES)
8891 	{
8892 	    // check for non-void type
8893 	    type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
8894 	    if (type->tt_type == VAR_VOID)
8895 	    {
8896 		semsg(_(e_expression_does_not_result_in_value_str), expr_start);
8897 		return NULL;
8898 	    }
8899 	}
8900 
8901 	++count;
8902 	prev = p;
8903 	p = skipwhite(p);
8904     }
8905 
8906     if (count > 0)
8907     {
8908 	long save_lnum = cctx->ctx_lnum;
8909 
8910 	// Use the line number where the command started.
8911 	cctx->ctx_lnum = start_ctx_lnum;
8912 
8913 	if (cmdidx == CMD_echo || cmdidx == CMD_echon)
8914 	    generate_ECHO(cctx, cmdidx == CMD_echo, count);
8915 	else if (cmdidx == CMD_execute)
8916 	    generate_MULT_EXPR(cctx, ISN_EXECUTE, count);
8917 	else if (cmdidx == CMD_echomsg)
8918 	    generate_MULT_EXPR(cctx, ISN_ECHOMSG, count);
8919 	else if (cmdidx == CMD_echoconsole)
8920 	    generate_MULT_EXPR(cctx, ISN_ECHOCONSOLE, count);
8921 	else
8922 	    generate_MULT_EXPR(cctx, ISN_ECHOERR, count);
8923 
8924 	cctx->ctx_lnum = save_lnum;
8925     }
8926     return p;
8927 }
8928 
8929 /*
8930  * If "eap" has a range that is not a constant generate an ISN_RANGE
8931  * instruction to compute it and return OK.
8932  * Otherwise return FAIL, the caller must deal with any range.
8933  */
8934     static int
8935 compile_variable_range(exarg_T *eap, cctx_T *cctx)
8936 {
8937     char_u *range_end = skip_range(eap->cmd, TRUE, NULL);
8938     char_u *p = skipdigits(eap->cmd);
8939 
8940     if (p == range_end)
8941 	return FAIL;
8942     return generate_RANGE(cctx, vim_strnsave(eap->cmd, range_end - eap->cmd));
8943 }
8944 
8945 /*
8946  * :put r
8947  * :put ={expr}
8948  */
8949     static char_u *
8950 compile_put(char_u *arg, exarg_T *eap, cctx_T *cctx)
8951 {
8952     char_u	*line = arg;
8953     linenr_T	lnum;
8954     char	*errormsg;
8955     int		above = eap->forceit;
8956 
8957     eap->regname = *line;
8958 
8959     if (eap->regname == '=')
8960     {
8961 	char_u *p = line + 1;
8962 
8963 	if (compile_expr0(&p, cctx) == FAIL)
8964 	    return NULL;
8965 	line = p;
8966     }
8967     else if (eap->regname != NUL)
8968 	++line;
8969 
8970     if (compile_variable_range(eap, cctx) == OK)
8971     {
8972 	lnum = above ? LNUM_VARIABLE_RANGE_ABOVE : LNUM_VARIABLE_RANGE;
8973     }
8974     else
8975     {
8976 	// Either no range or a number.
8977 	// "errormsg" will not be set because the range is ADDR_LINES.
8978 	if (parse_cmd_address(eap, &errormsg, FALSE) == FAIL)
8979 	    // cannot happen
8980 	    return NULL;
8981 	if (eap->addr_count == 0)
8982 	    lnum = -1;
8983 	else
8984 	    lnum = eap->line2;
8985 	if (above)
8986 	    --lnum;
8987     }
8988 
8989     generate_PUT(cctx, eap->regname, lnum);
8990     return line;
8991 }
8992 
8993 /*
8994  * A command that is not compiled, execute with legacy code.
8995  */
8996     static char_u *
8997 compile_exec(char_u *line_arg, exarg_T *eap, cctx_T *cctx)
8998 {
8999     char_u	*line = line_arg;
9000     char_u	*p;
9001     int		has_expr = FALSE;
9002     char_u	*nextcmd = (char_u *)"";
9003     char_u	*tofree = NULL;
9004 
9005     if (cctx->ctx_skip == SKIP_YES)
9006 	goto theend;
9007 
9008     // If there was a prececing command modifier, drop it and include it in the
9009     // EXEC command.
9010     if (cctx->ctx_has_cmdmod)
9011     {
9012 	garray_T	*instr = &cctx->ctx_instr;
9013 	isn_T		*isn = ((isn_T *)instr->ga_data) + instr->ga_len - 1;
9014 
9015 	if (isn->isn_type == ISN_CMDMOD)
9016 	{
9017 	    vim_regfree(isn->isn_arg.cmdmod.cf_cmdmod
9018 					       ->cmod_filter_regmatch.regprog);
9019 	    vim_free(isn->isn_arg.cmdmod.cf_cmdmod);
9020 	    --instr->ga_len;
9021 	    cctx->ctx_has_cmdmod = FALSE;
9022 	}
9023     }
9024 
9025     if (eap->cmdidx >= 0 && eap->cmdidx < CMD_SIZE)
9026     {
9027 	long	argt = eap->argt;
9028 	int	usefilter = FALSE;
9029 
9030 	has_expr = argt & (EX_XFILE | EX_EXPAND);
9031 
9032 	// If the command can be followed by a bar, find the bar and truncate
9033 	// it, so that the following command can be compiled.
9034 	// The '|' is overwritten with a NUL, it is put back below.
9035 	if ((eap->cmdidx == CMD_write || eap->cmdidx == CMD_read)
9036 							   && *eap->arg == '!')
9037 	    // :w !filter or :r !filter or :r! filter
9038 	    usefilter = TRUE;
9039 	if ((argt & EX_TRLBAR) && !usefilter)
9040 	{
9041 	    eap->argt = argt;
9042 	    separate_nextcmd(eap);
9043 	    if (eap->nextcmd != NULL)
9044 		nextcmd = eap->nextcmd;
9045 	}
9046 	else if (eap->cmdidx == CMD_wincmd)
9047 	{
9048 	    p = eap->arg;
9049 	    if (*p != NUL)
9050 		++p;
9051 	    if (*p == 'g' || *p == Ctrl_G)
9052 		++p;
9053 	    p = skipwhite(p);
9054 	    if (*p == '|')
9055 	    {
9056 		*p = NUL;
9057 		nextcmd = p + 1;
9058 	    }
9059 	}
9060 	else if (eap->cmdidx == CMD_command || eap->cmdidx == CMD_autocmd)
9061 	{
9062 	    // If there is a trailing '{' read lines until the '}'
9063 	    p = eap->arg + STRLEN(eap->arg) - 1;
9064 	    while (p > eap->arg && VIM_ISWHITE(*p))
9065 		--p;
9066 	    if (*p == '{')
9067 	    {
9068 		exarg_T ea;
9069 		int	flags;  // unused
9070 		int	start_lnum = SOURCING_LNUM;
9071 
9072 		CLEAR_FIELD(ea);
9073 		ea.arg = eap->arg;
9074 		fill_exarg_from_cctx(&ea, cctx);
9075 		(void)may_get_cmd_block(&ea, p, &tofree, &flags);
9076 		if (tofree != NULL)
9077 		{
9078 		    *p = NUL;
9079 		    line = concat_str(line, tofree);
9080 		    if (line == NULL)
9081 			goto theend;
9082 		    vim_free(tofree);
9083 		    tofree = line;
9084 		    SOURCING_LNUM = start_lnum;
9085 		}
9086 	    }
9087 	}
9088     }
9089 
9090     if (eap->cmdidx == CMD_syntax && STRNCMP(eap->arg, "include ", 8) == 0)
9091     {
9092 	// expand filename in "syntax include [@group] filename"
9093 	has_expr = TRUE;
9094 	eap->arg = skipwhite(eap->arg + 7);
9095 	if (*eap->arg == '@')
9096 	    eap->arg = skiptowhite(eap->arg);
9097     }
9098 
9099     if ((eap->cmdidx == CMD_global || eap->cmdidx == CMD_vglobal)
9100 						       && STRLEN(eap->arg) > 4)
9101     {
9102 	int delim = *eap->arg;
9103 
9104 	p = skip_regexp_ex(eap->arg + 1, delim, TRUE, NULL, NULL, NULL);
9105 	if (*p == delim)
9106 	{
9107 	    eap->arg = p + 1;
9108 	    has_expr = TRUE;
9109 	}
9110     }
9111 
9112     if (eap->cmdidx == CMD_folddoopen || eap->cmdidx == CMD_folddoclosed)
9113     {
9114 	// TODO: should only expand when appropriate for the command
9115 	eap->arg = skiptowhite(eap->arg);
9116 	has_expr = TRUE;
9117     }
9118 
9119     if (has_expr && (p = (char_u *)strstr((char *)eap->arg, "`=")) != NULL)
9120     {
9121 	int	count = 0;
9122 	char_u	*start = skipwhite(line);
9123 
9124 	// :cmd xxx`=expr1`yyy`=expr2`zzz
9125 	// PUSHS ":cmd xxx"
9126 	// eval expr1
9127 	// PUSHS "yyy"
9128 	// eval expr2
9129 	// PUSHS "zzz"
9130 	// EXECCONCAT 5
9131 	for (;;)
9132 	{
9133 	    if (p > start)
9134 	    {
9135 		char_u *val = vim_strnsave(start, p - start);
9136 
9137 		generate_PUSHS(cctx, &val);
9138 		++count;
9139 	    }
9140 	    p += 2;
9141 	    if (compile_expr0(&p, cctx) == FAIL)
9142 		return NULL;
9143 	    may_generate_2STRING(-1, TRUE, cctx);
9144 	    ++count;
9145 	    p = skipwhite(p);
9146 	    if (*p != '`')
9147 	    {
9148 		emsg(_(e_missing_backtick));
9149 		return NULL;
9150 	    }
9151 	    start = p + 1;
9152 
9153 	    p = (char_u *)strstr((char *)start, "`=");
9154 	    if (p == NULL)
9155 	    {
9156 		if (*skipwhite(start) != NUL)
9157 		{
9158 		    char_u *val = vim_strsave(start);
9159 
9160 		    generate_PUSHS(cctx, &val);
9161 		    ++count;
9162 		}
9163 		break;
9164 	    }
9165 	}
9166 	generate_EXECCONCAT(cctx, count);
9167     }
9168     else
9169 	generate_EXEC(cctx, ISN_EXEC, line);
9170 
9171 theend:
9172     if (*nextcmd != NUL)
9173     {
9174 	// the parser expects a pointer to the bar, put it back
9175 	--nextcmd;
9176 	*nextcmd = '|';
9177     }
9178     vim_free(tofree);
9179 
9180     return nextcmd;
9181 }
9182 
9183 /*
9184  * A script command with heredoc, e.g.
9185  *	ruby << EOF
9186  *	   command
9187  *	EOF
9188  * Has been turned into one long line with NL characters by
9189  * get_function_body():
9190  *	ruby << EOF<NL>   command<NL>EOF
9191  */
9192     static char_u *
9193 compile_script(char_u *line, cctx_T *cctx)
9194 {
9195     if (cctx->ctx_skip != SKIP_YES)
9196     {
9197 	isn_T	*isn;
9198 
9199 	if ((isn = generate_instr(cctx, ISN_EXEC_SPLIT)) == NULL)
9200 	    return NULL;
9201 	isn->isn_arg.string = vim_strsave(line);
9202     }
9203     return (char_u *)"";
9204 }
9205 
9206 
9207 /*
9208  * :s/pat/repl/
9209  */
9210     static char_u *
9211 compile_substitute(char_u *arg, exarg_T *eap, cctx_T *cctx)
9212 {
9213     char_u  *cmd = eap->arg;
9214     char_u  *expr = (char_u *)strstr((char *)cmd, "\\=");
9215 
9216     if (expr != NULL)
9217     {
9218 	int delimiter = *cmd++;
9219 
9220 	// There is a \=expr, find it in the substitute part.
9221 	cmd = skip_regexp_ex(cmd, delimiter, magic_isset(), NULL, NULL, NULL);
9222 	if (cmd[0] == delimiter && cmd[1] == '\\' && cmd[2] == '=')
9223 	{
9224 	    garray_T	save_ga = cctx->ctx_instr;
9225 	    char_u	*end;
9226 	    int		expr_res;
9227 	    int		trailing_error;
9228 	    int		instr_count;
9229 	    isn_T	*instr;
9230 	    isn_T	*isn;
9231 
9232 	    cmd += 3;
9233 	    end = skip_substitute(cmd, delimiter);
9234 
9235 	    // Temporarily reset the list of instructions so that the jump
9236 	    // labels are correct.
9237 	    cctx->ctx_instr.ga_len = 0;
9238 	    cctx->ctx_instr.ga_maxlen = 0;
9239 	    cctx->ctx_instr.ga_data = NULL;
9240 	    expr_res = compile_expr0(&cmd, cctx);
9241 	    if (end[-1] == NUL)
9242 		end[-1] = delimiter;
9243 	    cmd = skipwhite(cmd);
9244 	    trailing_error = *cmd != delimiter && *cmd != NUL;
9245 
9246 	    if (expr_res == FAIL || trailing_error
9247 				       || GA_GROW_FAILS(&cctx->ctx_instr, 1))
9248 	    {
9249 		if (trailing_error)
9250 		    semsg(_(e_trailing_arg), cmd);
9251 		clear_instr_ga(&cctx->ctx_instr);
9252 		cctx->ctx_instr = save_ga;
9253 		return NULL;
9254 	    }
9255 
9256 	    // Move the generated instructions into the ISN_SUBSTITUTE
9257 	    // instructions, then restore the list of instructions before
9258 	    // adding the ISN_SUBSTITUTE instruction.
9259 	    instr_count = cctx->ctx_instr.ga_len;
9260 	    instr = cctx->ctx_instr.ga_data;
9261 	    instr[instr_count].isn_type = ISN_FINISH;
9262 
9263 	    cctx->ctx_instr = save_ga;
9264 	    if ((isn = generate_instr(cctx, ISN_SUBSTITUTE)) == NULL)
9265 	    {
9266 		int idx;
9267 
9268 		for (idx = 0; idx < instr_count; ++idx)
9269 		    delete_instr(instr + idx);
9270 		vim_free(instr);
9271 		return NULL;
9272 	    }
9273 	    isn->isn_arg.subs.subs_cmd = vim_strsave(arg);
9274 	    isn->isn_arg.subs.subs_instr = instr;
9275 
9276 	    // skip over flags
9277 	    if (*end == '&')
9278 		++end;
9279 	    while (ASCII_ISALPHA(*end) || *end == '#')
9280 		++end;
9281 	    return end;
9282 	}
9283     }
9284 
9285     return compile_exec(arg, eap, cctx);
9286 }
9287 
9288     static char_u *
9289 compile_redir(char_u *line, exarg_T *eap, cctx_T *cctx)
9290 {
9291     char_u *arg = eap->arg;
9292     lhs_T	*lhs = &cctx->ctx_redir_lhs;
9293 
9294     if (lhs->lhs_name != NULL)
9295     {
9296 	if (STRNCMP(arg, "END", 3) == 0)
9297 	{
9298 	    if (lhs->lhs_append)
9299 	    {
9300 		// First load the current variable value.
9301 		if (compile_load_lhs_with_index(lhs, lhs->lhs_whole,
9302 								 cctx) == FAIL)
9303 		    return NULL;
9304 	    }
9305 
9306 	    // Gets the redirected text and put it on the stack, then store it
9307 	    // in the variable.
9308 	    generate_instr_type(cctx, ISN_REDIREND, &t_string);
9309 
9310 	    if (lhs->lhs_append)
9311 		generate_instr_drop(cctx, ISN_CONCAT, 1);
9312 
9313 	    if (lhs->lhs_has_index)
9314 	    {
9315 		// Use the info in "lhs" to store the value at the index in the
9316 		// list or dict.
9317 		if (compile_assign_unlet(lhs->lhs_whole, lhs, TRUE,
9318 						      &t_string, cctx) == FAIL)
9319 		    return NULL;
9320 	    }
9321 	    else if (generate_store_lhs(cctx, lhs, -1) == FAIL)
9322 		return NULL;
9323 
9324 	    VIM_CLEAR(lhs->lhs_name);
9325 	    VIM_CLEAR(lhs->lhs_whole);
9326 	    return arg + 3;
9327 	}
9328 	emsg(_(e_cannot_nest_redir));
9329 	return NULL;
9330     }
9331 
9332     if (arg[0] == '=' && arg[1] == '>')
9333     {
9334 	int	    append = FALSE;
9335 
9336 	// redirect to a variable is compiled
9337 	arg += 2;
9338 	if (*arg == '>')
9339 	{
9340 	    ++arg;
9341 	    append = TRUE;
9342 	}
9343 	arg = skipwhite(arg);
9344 
9345 	if (compile_assign_lhs(arg, lhs, CMD_redir,
9346 						FALSE, FALSE, 1, cctx) == FAIL)
9347 	    return NULL;
9348 	generate_instr(cctx, ISN_REDIRSTART);
9349 	lhs->lhs_append = append;
9350 	if (lhs->lhs_has_index)
9351 	{
9352 	    lhs->lhs_whole = vim_strnsave(arg, lhs->lhs_varlen_total);
9353 	    if (lhs->lhs_whole == NULL)
9354 		return NULL;
9355 	}
9356 
9357 	return arg + lhs->lhs_varlen_total;
9358     }
9359 
9360     // other redirects are handled like at script level
9361     return compile_exec(line, eap, cctx);
9362 }
9363 
9364 #ifdef FEAT_QUICKFIX
9365     static char_u *
9366 compile_cexpr(char_u *line, exarg_T *eap, cctx_T *cctx)
9367 {
9368     isn_T	*isn;
9369     char_u	*p;
9370 
9371     isn = generate_instr(cctx, ISN_CEXPR_AUCMD);
9372     if (isn == NULL)
9373 	return NULL;
9374     isn->isn_arg.number = eap->cmdidx;
9375 
9376     p = eap->arg;
9377     if (compile_expr0(&p, cctx) == FAIL)
9378 	return NULL;
9379 
9380     isn = generate_instr(cctx, ISN_CEXPR_CORE);
9381     if (isn == NULL)
9382 	return NULL;
9383     isn->isn_arg.cexpr.cexpr_ref = ALLOC_ONE(cexprref_T);
9384     if (isn->isn_arg.cexpr.cexpr_ref == NULL)
9385 	return NULL;
9386     isn->isn_arg.cexpr.cexpr_ref->cer_cmdidx = eap->cmdidx;
9387     isn->isn_arg.cexpr.cexpr_ref->cer_forceit = eap->forceit;
9388     isn->isn_arg.cexpr.cexpr_ref->cer_cmdline = vim_strsave(skipwhite(line));
9389 
9390     return p;
9391 }
9392 #endif
9393 
9394 /*
9395  * Add a function to the list of :def functions.
9396  * This sets "ufunc->uf_dfunc_idx" but the function isn't compiled yet.
9397  */
9398     static int
9399 add_def_function(ufunc_T *ufunc)
9400 {
9401     dfunc_T *dfunc;
9402 
9403     if (def_functions.ga_len == 0)
9404     {
9405 	// The first position is not used, so that a zero uf_dfunc_idx means it
9406 	// wasn't set.
9407 	if (GA_GROW_FAILS(&def_functions, 1))
9408 	    return FAIL;
9409 	++def_functions.ga_len;
9410     }
9411 
9412     // Add the function to "def_functions".
9413     if (GA_GROW_FAILS(&def_functions, 1))
9414 	return FAIL;
9415     dfunc = ((dfunc_T *)def_functions.ga_data) + def_functions.ga_len;
9416     CLEAR_POINTER(dfunc);
9417     dfunc->df_idx = def_functions.ga_len;
9418     ufunc->uf_dfunc_idx = dfunc->df_idx;
9419     dfunc->df_ufunc = ufunc;
9420     dfunc->df_name = vim_strsave(ufunc->uf_name);
9421     ga_init2(&dfunc->df_var_names, sizeof(char_u *), 10);
9422     ++dfunc->df_refcount;
9423     ++def_functions.ga_len;
9424     return OK;
9425 }
9426 
9427 /*
9428  * After ex_function() has collected all the function lines: parse and compile
9429  * the lines into instructions.
9430  * Adds the function to "def_functions".
9431  * When "check_return_type" is set then set ufunc->uf_ret_type to the type of
9432  * the return statement (used for lambda).  When uf_ret_type is already set
9433  * then check that it matches.
9434  * When "profiling" is true add ISN_PROF_START instructions.
9435  * "outer_cctx" is set for a nested function.
9436  * This can be used recursively through compile_lambda(), which may reallocate
9437  * "def_functions".
9438  * Returns OK or FAIL.
9439  */
9440     int
9441 compile_def_function(
9442 	ufunc_T		*ufunc,
9443 	int		check_return_type,
9444 	compiletype_T   compile_type,
9445 	cctx_T		*outer_cctx)
9446 {
9447     char_u	*line = NULL;
9448     char_u	*line_to_free = NULL;
9449     char_u	*p;
9450     char	*errormsg = NULL;	// error message
9451     cctx_T	cctx;
9452     garray_T	*instr;
9453     int		did_emsg_before = did_emsg;
9454     int		did_emsg_silent_before = did_emsg_silent;
9455     int		ret = FAIL;
9456     sctx_T	save_current_sctx = current_sctx;
9457     int		save_estack_compiling = estack_compiling;
9458     int		save_cmod_flags = cmdmod.cmod_flags;
9459     int		do_estack_push;
9460     int		new_def_function = FALSE;
9461 #ifdef FEAT_PROFILE
9462     int		prof_lnum = -1;
9463 #endif
9464     int		debug_lnum = -1;
9465 
9466     // When using a function that was compiled before: Free old instructions.
9467     // The index is reused.  Otherwise add a new entry in "def_functions".
9468     if (ufunc->uf_dfunc_idx > 0)
9469     {
9470 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
9471 							 + ufunc->uf_dfunc_idx;
9472 	isn_T	*instr_dest = NULL;
9473 
9474 	switch (compile_type)
9475 	{
9476 	    case CT_PROFILE:
9477 #ifdef FEAT_PROFILE
9478 			    instr_dest = dfunc->df_instr_prof; break;
9479 #endif
9480 	    case CT_NONE:   instr_dest = dfunc->df_instr; break;
9481 	    case CT_DEBUG:  instr_dest = dfunc->df_instr_debug; break;
9482 	}
9483 	if (instr_dest != NULL)
9484 	    // Was compiled in this mode before: Free old instructions.
9485 	    delete_def_function_contents(dfunc, FALSE);
9486 	ga_clear_strings(&dfunc->df_var_names);
9487     }
9488     else
9489     {
9490 	if (add_def_function(ufunc) == FAIL)
9491 	    return FAIL;
9492 	new_def_function = TRUE;
9493     }
9494 
9495     ufunc->uf_def_status = UF_COMPILING;
9496 
9497     CLEAR_FIELD(cctx);
9498 
9499     cctx.ctx_compile_type = compile_type;
9500     cctx.ctx_ufunc = ufunc;
9501     cctx.ctx_lnum = -1;
9502     cctx.ctx_outer = outer_cctx;
9503     ga_init2(&cctx.ctx_locals, sizeof(lvar_T), 10);
9504     ga_init2(&cctx.ctx_type_stack, sizeof(type_T *), 50);
9505     ga_init2(&cctx.ctx_imports, sizeof(imported_T), 10);
9506     cctx.ctx_type_list = &ufunc->uf_type_list;
9507     ga_init2(&cctx.ctx_instr, sizeof(isn_T), 50);
9508     instr = &cctx.ctx_instr;
9509 
9510     // Set the context to the function, it may be compiled when called from
9511     // another script.  Set the script version to the most modern one.
9512     // The line number will be set in next_line_from_context().
9513     current_sctx = ufunc->uf_script_ctx;
9514     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
9515 
9516     // Don't use the flag from ":legacy" here.
9517     cmdmod.cmod_flags &= ~CMOD_LEGACY;
9518 
9519     // Make sure error messages are OK.
9520     do_estack_push = !estack_top_is_ufunc(ufunc, 1);
9521     if (do_estack_push)
9522 	estack_push_ufunc(ufunc, 1);
9523     estack_compiling = TRUE;
9524 
9525     if (ufunc->uf_def_args.ga_len > 0)
9526     {
9527 	int	count = ufunc->uf_def_args.ga_len;
9528 	int	first_def_arg = ufunc->uf_args.ga_len - count;
9529 	int	i;
9530 	char_u	*arg;
9531 	int	off = STACK_FRAME_SIZE + (ufunc->uf_va_name != NULL ? 1 : 0);
9532 	int	did_set_arg_type = FALSE;
9533 
9534 	// Produce instructions for the default values of optional arguments.
9535 	SOURCING_LNUM = 0;  // line number unknown
9536 	for (i = 0; i < count; ++i)
9537 	{
9538 	    garray_T	*stack = &cctx.ctx_type_stack;
9539 	    type_T	*val_type;
9540 	    int		arg_idx = first_def_arg + i;
9541 	    where_T	where = WHERE_INIT;
9542 	    int		r;
9543 	    int		jump_instr_idx = instr->ga_len;
9544 	    isn_T	*isn;
9545 
9546 	    // Use a JUMP_IF_ARG_SET instruction to skip if the value was given.
9547 	    if (generate_JUMP_IF_ARG_SET(&cctx, i - count - off) == FAIL)
9548 		goto erret;
9549 
9550 	    // Make sure later arguments are not found.
9551 	    ufunc->uf_args_visible = arg_idx;
9552 
9553 	    arg = ((char_u **)(ufunc->uf_def_args.ga_data))[i];
9554 	    r = compile_expr0(&arg, &cctx);
9555 
9556 	    if (r == FAIL)
9557 		goto erret;
9558 
9559 	    // If no type specified use the type of the default value.
9560 	    // Otherwise check that the default value type matches the
9561 	    // specified type.
9562 	    val_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
9563 	    where.wt_index = arg_idx + 1;
9564 	    if (ufunc->uf_arg_types[arg_idx] == &t_unknown)
9565 	    {
9566 		did_set_arg_type = TRUE;
9567 		ufunc->uf_arg_types[arg_idx] = val_type;
9568 	    }
9569 	    else if (check_type(ufunc->uf_arg_types[arg_idx], val_type,
9570 							  TRUE, where) == FAIL)
9571 		goto erret;
9572 
9573 	    if (generate_STORE(&cctx, ISN_STORE, i - count - off, NULL) == FAIL)
9574 		goto erret;
9575 
9576 	    // set instruction index in JUMP_IF_ARG_SET to here
9577 	    isn = ((isn_T *)instr->ga_data) + jump_instr_idx;
9578 	    isn->isn_arg.jumparg.jump_where = instr->ga_len;
9579 	}
9580 
9581 	if (did_set_arg_type)
9582 	    set_function_type(ufunc);
9583     }
9584     ufunc->uf_args_visible = ufunc->uf_args.ga_len;
9585 
9586     /*
9587      * Loop over all the lines of the function and generate instructions.
9588      */
9589     for (;;)
9590     {
9591 	exarg_T	    ea;
9592 	int	    starts_with_colon = FALSE;
9593 	char_u	    *cmd;
9594 	cmdmod_T    local_cmdmod;
9595 
9596 	// Bail out on the first error to avoid a flood of errors and report
9597 	// the right line number when inside try/catch.
9598 	if (did_emsg_before != did_emsg)
9599 	    goto erret;
9600 
9601 	if (line != NULL && *line == '|')
9602 	    // the line continues after a '|'
9603 	    ++line;
9604 	else if (line != NULL && *skipwhite(line) != NUL
9605 		&& !(*line == '#' && (line == cctx.ctx_line_start
9606 						    || VIM_ISWHITE(line[-1]))))
9607 	{
9608 	    semsg(_(e_trailing_arg), line);
9609 	    goto erret;
9610 	}
9611 	else if (line != NULL && vim9_bad_comment(skipwhite(line)))
9612 	    goto erret;
9613 	else
9614 	{
9615 	    line = next_line_from_context(&cctx, FALSE);
9616 	    if (cctx.ctx_lnum >= ufunc->uf_lines.ga_len)
9617 	    {
9618 		// beyond the last line
9619 #ifdef FEAT_PROFILE
9620 		if (cctx.ctx_skip != SKIP_YES)
9621 		    may_generate_prof_end(&cctx, prof_lnum);
9622 #endif
9623 		break;
9624 	    }
9625 	    // Make a copy, splitting off nextcmd and removing trailing spaces
9626 	    // may change it.
9627 	    if (line != NULL)
9628 	    {
9629 		line = vim_strsave(line);
9630 		vim_free(line_to_free);
9631 		line_to_free = line;
9632 	    }
9633 	}
9634 
9635 	CLEAR_FIELD(ea);
9636 	ea.cmdlinep = &line;
9637 	ea.cmd = skipwhite(line);
9638 
9639 	if (*ea.cmd == '#')
9640 	{
9641 	    // "#" starts a comment
9642 	    line = (char_u *)"";
9643 	    continue;
9644 	}
9645 
9646 #ifdef FEAT_PROFILE
9647 	if (cctx.ctx_compile_type == CT_PROFILE && cctx.ctx_lnum != prof_lnum
9648 						  && cctx.ctx_skip != SKIP_YES)
9649 	{
9650 	    may_generate_prof_end(&cctx, prof_lnum);
9651 
9652 	    prof_lnum = cctx.ctx_lnum;
9653 	    generate_instr(&cctx, ISN_PROF_START);
9654 	}
9655 #endif
9656 	if (cctx.ctx_compile_type == CT_DEBUG && cctx.ctx_lnum != debug_lnum
9657 						  && cctx.ctx_skip != SKIP_YES)
9658 	{
9659 	    debug_lnum = cctx.ctx_lnum;
9660 	    generate_instr_debug(&cctx);
9661 	}
9662 	cctx.ctx_prev_lnum = cctx.ctx_lnum + 1;
9663 
9664 	// Some things can be recognized by the first character.
9665 	switch (*ea.cmd)
9666 	{
9667 	    case '}':
9668 		{
9669 		    // "}" ends a block scope
9670 		    scopetype_T stype = cctx.ctx_scope == NULL
9671 					  ? NO_SCOPE : cctx.ctx_scope->se_type;
9672 
9673 		    if (stype == BLOCK_SCOPE)
9674 		    {
9675 			compile_endblock(&cctx);
9676 			line = ea.cmd;
9677 		    }
9678 		    else
9679 		    {
9680 			emsg(_(e_using_rcurly_outside_if_block_scope));
9681 			goto erret;
9682 		    }
9683 		    if (line != NULL)
9684 			line = skipwhite(ea.cmd + 1);
9685 		    continue;
9686 		}
9687 
9688 	    case '{':
9689 		// "{" starts a block scope
9690 		// "{'a': 1}->func() is something else
9691 		if (ends_excmd(*skipwhite(ea.cmd + 1)))
9692 		{
9693 		    line = compile_block(ea.cmd, &cctx);
9694 		    continue;
9695 		}
9696 		break;
9697 	}
9698 
9699 	/*
9700 	 * COMMAND MODIFIERS
9701 	 */
9702 	cctx.ctx_has_cmdmod = FALSE;
9703 	if (parse_command_modifiers(&ea, &errormsg, &local_cmdmod, FALSE)
9704 								       == FAIL)
9705 	{
9706 	    if (errormsg != NULL)
9707 		goto erret;
9708 	    // empty line or comment
9709 	    line = (char_u *)"";
9710 	    continue;
9711 	}
9712 	generate_cmdmods(&cctx, &local_cmdmod);
9713 	undo_cmdmod(&local_cmdmod);
9714 
9715 	// Check if there was a colon after the last command modifier or before
9716 	// the current position.
9717 	for (p = ea.cmd; p >= line; --p)
9718 	{
9719 	    if (*p == ':')
9720 		starts_with_colon = TRUE;
9721 	    if (p < ea.cmd && !VIM_ISWHITE(*p))
9722 		break;
9723 	}
9724 
9725 	// Skip ":call" to get to the function name, unless using :legacy
9726 	p = ea.cmd;
9727 	if (!(local_cmdmod.cmod_flags & CMOD_LEGACY))
9728 	{
9729 	    if (checkforcmd(&ea.cmd, "call", 3))
9730 	    {
9731 		if (*ea.cmd == '(')
9732 		    // not for "call()"
9733 		    ea.cmd = p;
9734 		else
9735 		    ea.cmd = skipwhite(ea.cmd);
9736 	    }
9737 
9738 	    if (!starts_with_colon)
9739 	    {
9740 		int	    assign;
9741 
9742 		// Check for assignment after command modifiers.
9743 		assign = may_compile_assignment(&ea, &line, &cctx);
9744 		if (assign == OK)
9745 		    goto nextline;
9746 		if (assign == FAIL)
9747 		    goto erret;
9748 	    }
9749 	}
9750 
9751 	/*
9752 	 * COMMAND after range
9753 	 * 'text'->func() should not be confused with 'a mark
9754 	 * "++nr" and "--nr" are eval commands
9755 	 * in "$ENV->func()" the "$" is not a range
9756 	 */
9757 	cmd = ea.cmd;
9758 	if (!(local_cmdmod.cmod_flags & CMOD_LEGACY)
9759 		&& (*cmd != '$' || starts_with_colon)
9760 		&& (starts_with_colon || !(*cmd == '\''
9761 		       || (cmd[0] == cmd[1] && (*cmd == '+' || *cmd == '-')))))
9762 	{
9763 	    ea.cmd = skip_range(ea.cmd, TRUE, NULL);
9764 	    if (ea.cmd > cmd)
9765 	    {
9766 		if (!starts_with_colon)
9767 		{
9768 		    semsg(_(e_colon_required_before_range_str), cmd);
9769 		    goto erret;
9770 		}
9771 		ea.addr_count = 1;
9772 		if (ends_excmd2(line, ea.cmd))
9773 		{
9774 		    // A range without a command: jump to the line.
9775 		    // TODO: compile to a more efficient command, possibly
9776 		    // calling parse_cmd_address().
9777 		    ea.cmdidx = CMD_SIZE;
9778 		    line = compile_exec(line, &ea, &cctx);
9779 		    goto nextline;
9780 		}
9781 	    }
9782 	}
9783 	p = find_ex_command(&ea, NULL,
9784 		starts_with_colon || (local_cmdmod.cmod_flags & CMOD_LEGACY)
9785 						  ? NULL : item_exists, &cctx);
9786 
9787 	if (p == NULL)
9788 	{
9789 	    if (cctx.ctx_skip != SKIP_YES)
9790 		emsg(_(e_ambiguous_use_of_user_defined_command));
9791 	    goto erret;
9792 	}
9793 
9794 	// When using ":legacy cmd" always use compile_exec().
9795 	if (local_cmdmod.cmod_flags & CMOD_LEGACY)
9796 	{
9797 	    char_u *start = ea.cmd;
9798 
9799 	    switch (ea.cmdidx)
9800 	    {
9801 		case CMD_if:
9802 		case CMD_elseif:
9803 		case CMD_else:
9804 		case CMD_endif:
9805 		case CMD_for:
9806 		case CMD_endfor:
9807 		case CMD_continue:
9808 		case CMD_break:
9809 		case CMD_while:
9810 		case CMD_endwhile:
9811 		case CMD_try:
9812 		case CMD_catch:
9813 		case CMD_finally:
9814 		case CMD_endtry:
9815 			semsg(_(e_cannot_use_legacy_with_command_str), ea.cmd);
9816 			goto erret;
9817 		default: break;
9818 	    }
9819 
9820 	    // ":legacy return expr" needs to be handled differently.
9821 	    if (checkforcmd(&start, "return", 4))
9822 		ea.cmdidx = CMD_return;
9823 	    else
9824 		ea.cmdidx = CMD_legacy;
9825 	}
9826 
9827 	if (p == ea.cmd && ea.cmdidx != CMD_SIZE)
9828 	{
9829 	    if (cctx.ctx_skip == SKIP_YES && ea.cmdidx != CMD_eval)
9830 	    {
9831 		line += STRLEN(line);
9832 		goto nextline;
9833 	    }
9834 	    else if (ea.cmdidx != CMD_eval)
9835 	    {
9836 		// CMD_var cannot happen, compile_assignment() above would be
9837 		// used.  Most likely an assignment to a non-existing variable.
9838 		semsg(_(e_command_not_recognized_str), ea.cmd);
9839 		goto erret;
9840 	    }
9841 	}
9842 
9843 	if (cctx.ctx_had_return
9844 		&& ea.cmdidx != CMD_elseif
9845 		&& ea.cmdidx != CMD_else
9846 		&& ea.cmdidx != CMD_endif
9847 		&& ea.cmdidx != CMD_endfor
9848 		&& ea.cmdidx != CMD_endwhile
9849 		&& ea.cmdidx != CMD_catch
9850 		&& ea.cmdidx != CMD_finally
9851 		&& ea.cmdidx != CMD_endtry)
9852 	{
9853 	    emsg(_(e_unreachable_code_after_return));
9854 	    goto erret;
9855 	}
9856 
9857 	p = skipwhite(p);
9858 	if (ea.cmdidx != CMD_SIZE
9859 			    && ea.cmdidx != CMD_write && ea.cmdidx != CMD_read)
9860 	{
9861 	    if (ea.cmdidx >= 0)
9862 		ea.argt = excmd_get_argt(ea.cmdidx);
9863 	    if ((ea.argt & EX_BANG) && *p == '!')
9864 	    {
9865 		ea.forceit = TRUE;
9866 		p = skipwhite(p + 1);
9867 	    }
9868 	}
9869 
9870 	switch (ea.cmdidx)
9871 	{
9872 	    case CMD_def:
9873 		    ea.arg = p;
9874 		    line = compile_nested_function(&ea, &cctx);
9875 		    break;
9876 
9877 	    case CMD_function:
9878 		    // TODO: should we allow this, e.g. to declare a global
9879 		    // function?
9880 		    emsg(_(e_cannot_use_function_inside_def));
9881 		    goto erret;
9882 
9883 	    case CMD_return:
9884 		    line = compile_return(p, check_return_type,
9885 				 local_cmdmod.cmod_flags & CMOD_LEGACY, &cctx);
9886 		    cctx.ctx_had_return = TRUE;
9887 		    break;
9888 
9889 	    case CMD_let:
9890 		    emsg(_(e_cannot_use_let_in_vim9_script));
9891 		    break;
9892 	    case CMD_var:
9893 	    case CMD_final:
9894 	    case CMD_const:
9895 	    case CMD_increment:
9896 	    case CMD_decrement:
9897 		    line = compile_assignment(p, &ea, ea.cmdidx, &cctx);
9898 		    if (line == p)
9899 			line = NULL;
9900 		    break;
9901 
9902 	    case CMD_unlet:
9903 	    case CMD_unlockvar:
9904 	    case CMD_lockvar:
9905 		    line = compile_unletlock(p, &ea, &cctx);
9906 		    break;
9907 
9908 	    case CMD_import:
9909 		    emsg(_(e_import_can_only_be_used_in_script));
9910 		    line = NULL;
9911 		    break;
9912 
9913 	    case CMD_if:
9914 		    line = compile_if(p, &cctx);
9915 		    break;
9916 	    case CMD_elseif:
9917 		    line = compile_elseif(p, &cctx);
9918 		    cctx.ctx_had_return = FALSE;
9919 		    break;
9920 	    case CMD_else:
9921 		    line = compile_else(p, &cctx);
9922 		    cctx.ctx_had_return = FALSE;
9923 		    break;
9924 	    case CMD_endif:
9925 		    line = compile_endif(p, &cctx);
9926 		    break;
9927 
9928 	    case CMD_while:
9929 		    line = compile_while(p, &cctx);
9930 		    break;
9931 	    case CMD_endwhile:
9932 		    line = compile_endwhile(p, &cctx);
9933 		    cctx.ctx_had_return = FALSE;
9934 		    break;
9935 
9936 	    case CMD_for:
9937 		    line = compile_for(p, &cctx);
9938 		    break;
9939 	    case CMD_endfor:
9940 		    line = compile_endfor(p, &cctx);
9941 		    cctx.ctx_had_return = FALSE;
9942 		    break;
9943 	    case CMD_continue:
9944 		    line = compile_continue(p, &cctx);
9945 		    break;
9946 	    case CMD_break:
9947 		    line = compile_break(p, &cctx);
9948 		    break;
9949 
9950 	    case CMD_try:
9951 		    line = compile_try(p, &cctx);
9952 		    break;
9953 	    case CMD_catch:
9954 		    line = compile_catch(p, &cctx);
9955 		    cctx.ctx_had_return = FALSE;
9956 		    break;
9957 	    case CMD_finally:
9958 		    line = compile_finally(p, &cctx);
9959 		    cctx.ctx_had_return = FALSE;
9960 		    break;
9961 	    case CMD_endtry:
9962 		    line = compile_endtry(p, &cctx);
9963 		    cctx.ctx_had_return = FALSE;
9964 		    break;
9965 	    case CMD_throw:
9966 		    line = compile_throw(p, &cctx);
9967 		    break;
9968 
9969 	    case CMD_eval:
9970 		    line = compile_eval(p, &cctx);
9971 		    break;
9972 
9973 	    case CMD_echo:
9974 	    case CMD_echon:
9975 	    case CMD_execute:
9976 	    case CMD_echomsg:
9977 	    case CMD_echoerr:
9978 	    case CMD_echoconsole:
9979 		    line = compile_mult_expr(p, ea.cmdidx, &cctx);
9980 		    break;
9981 
9982 	    case CMD_put:
9983 		    ea.cmd = cmd;
9984 		    line = compile_put(p, &ea, &cctx);
9985 		    break;
9986 
9987 	    case CMD_substitute:
9988 		    if (cctx.ctx_skip == SKIP_YES)
9989 			line = (char_u *)"";
9990 		    else
9991 		    {
9992 			ea.arg = p;
9993 			line = compile_substitute(line, &ea, &cctx);
9994 		    }
9995 		    break;
9996 
9997 	    case CMD_redir:
9998 		    ea.arg = p;
9999 		    line = compile_redir(line, &ea, &cctx);
10000 		    break;
10001 
10002 	    case CMD_cexpr:
10003 	    case CMD_lexpr:
10004 	    case CMD_caddexpr:
10005 	    case CMD_laddexpr:
10006 	    case CMD_cgetexpr:
10007 	    case CMD_lgetexpr:
10008 #ifdef FEAT_QUICKFIX
10009 		    ea.arg = p;
10010 		    line = compile_cexpr(line, &ea, &cctx);
10011 #else
10012 		    ex_ni(&ea);
10013 		    line = NULL;
10014 #endif
10015 		    break;
10016 
10017 	    case CMD_append:
10018 	    case CMD_change:
10019 	    case CMD_insert:
10020 	    case CMD_k:
10021 	    case CMD_t:
10022 	    case CMD_xit:
10023 		    not_in_vim9(&ea);
10024 		    goto erret;
10025 
10026 	    case CMD_SIZE:
10027 		    if (cctx.ctx_skip != SKIP_YES)
10028 		    {
10029 			semsg(_(e_invalid_command_str), ea.cmd);
10030 			goto erret;
10031 		    }
10032 		    // We don't check for a next command here.
10033 		    line = (char_u *)"";
10034 		    break;
10035 
10036 	    case CMD_lua:
10037 	    case CMD_mzscheme:
10038 	    case CMD_perl:
10039 	    case CMD_py3:
10040 	    case CMD_python3:
10041 	    case CMD_python:
10042 	    case CMD_pythonx:
10043 	    case CMD_ruby:
10044 	    case CMD_tcl:
10045 		    ea.arg = p;
10046 		    if (vim_strchr(line, '\n') == NULL)
10047 			line = compile_exec(line, &ea, &cctx);
10048 		    else
10049 			// heredoc lines have been concatenated with NL
10050 			// characters in get_function_body()
10051 			line = compile_script(line, &cctx);
10052 		    break;
10053 
10054 	    default:
10055 		    // Not recognized, execute with do_cmdline_cmd().
10056 		    ea.arg = p;
10057 		    line = compile_exec(line, &ea, &cctx);
10058 		    break;
10059 	}
10060 nextline:
10061 	if (line == NULL)
10062 	    goto erret;
10063 	line = skipwhite(line);
10064 
10065 	// Undo any command modifiers.
10066 	generate_undo_cmdmods(&cctx);
10067 
10068 	if (cctx.ctx_type_stack.ga_len < 0)
10069 	{
10070 	    iemsg("Type stack underflow");
10071 	    goto erret;
10072 	}
10073     }
10074 
10075     if (cctx.ctx_scope != NULL)
10076     {
10077 	if (cctx.ctx_scope->se_type == IF_SCOPE)
10078 	    emsg(_(e_endif));
10079 	else if (cctx.ctx_scope->se_type == WHILE_SCOPE)
10080 	    emsg(_(e_endwhile));
10081 	else if (cctx.ctx_scope->se_type == FOR_SCOPE)
10082 	    emsg(_(e_endfor));
10083 	else
10084 	    emsg(_(e_missing_rcurly));
10085 	goto erret;
10086     }
10087 
10088     if (!cctx.ctx_had_return)
10089     {
10090 	if (ufunc->uf_ret_type->tt_type == VAR_UNKNOWN)
10091 	    ufunc->uf_ret_type = &t_void;
10092 	else if (ufunc->uf_ret_type->tt_type != VAR_VOID)
10093 	{
10094 	    emsg(_(e_missing_return_statement));
10095 	    goto erret;
10096 	}
10097 
10098 	// Return void if there is no return at the end.
10099 	generate_instr(&cctx, ISN_RETURN_VOID);
10100     }
10101 
10102     // When compiled with ":silent!" and there was an error don't consider the
10103     // function compiled.
10104     if (emsg_silent == 0 || did_emsg_silent == did_emsg_silent_before)
10105     {
10106 	dfunc_T	*dfunc = ((dfunc_T *)def_functions.ga_data)
10107 							 + ufunc->uf_dfunc_idx;
10108 	dfunc->df_deleted = FALSE;
10109 	dfunc->df_script_seq = current_sctx.sc_seq;
10110 #ifdef FEAT_PROFILE
10111 	if (cctx.ctx_compile_type == CT_PROFILE)
10112 	{
10113 	    dfunc->df_instr_prof = instr->ga_data;
10114 	    dfunc->df_instr_prof_count = instr->ga_len;
10115 	}
10116 	else
10117 #endif
10118 	if (cctx.ctx_compile_type == CT_DEBUG)
10119 	{
10120 	    dfunc->df_instr_debug = instr->ga_data;
10121 	    dfunc->df_instr_debug_count = instr->ga_len;
10122 	}
10123 	else
10124 	{
10125 	    dfunc->df_instr = instr->ga_data;
10126 	    dfunc->df_instr_count = instr->ga_len;
10127 	}
10128 	dfunc->df_varcount = dfunc->df_var_names.ga_len;
10129 	dfunc->df_has_closure = cctx.ctx_has_closure;
10130 	if (cctx.ctx_outer_used)
10131 	    ufunc->uf_flags |= FC_CLOSURE;
10132 	ufunc->uf_def_status = UF_COMPILED;
10133     }
10134 
10135     ret = OK;
10136 
10137 erret:
10138     if (ufunc->uf_def_status == UF_COMPILING)
10139     {
10140 	dfunc_T	*dfunc = ((dfunc_T *)def_functions.ga_data)
10141 							 + ufunc->uf_dfunc_idx;
10142 
10143 	// Compiling aborted, free the generated instructions.
10144 	clear_instr_ga(instr);
10145 	VIM_CLEAR(dfunc->df_name);
10146 	ga_clear_strings(&dfunc->df_var_names);
10147 
10148 	// If using the last entry in the table and it was added above, we
10149 	// might as well remove it.
10150 	if (!dfunc->df_deleted && new_def_function
10151 			    && ufunc->uf_dfunc_idx == def_functions.ga_len - 1)
10152 	{
10153 	    --def_functions.ga_len;
10154 	    ufunc->uf_dfunc_idx = 0;
10155 	}
10156 	ufunc->uf_def_status = UF_COMPILE_ERROR;
10157 
10158 	while (cctx.ctx_scope != NULL)
10159 	    drop_scope(&cctx);
10160 
10161 	if (errormsg != NULL)
10162 	    emsg(errormsg);
10163 	else if (did_emsg == did_emsg_before)
10164 	    emsg(_(e_compiling_def_function_failed));
10165     }
10166 
10167     if (cctx.ctx_redir_lhs.lhs_name != NULL)
10168     {
10169 	if (ret == OK)
10170 	{
10171 	    emsg(_(e_missing_redir_end));
10172 	    ret = FAIL;
10173 	}
10174 	vim_free(cctx.ctx_redir_lhs.lhs_name);
10175 	vim_free(cctx.ctx_redir_lhs.lhs_whole);
10176     }
10177 
10178     current_sctx = save_current_sctx;
10179     estack_compiling = save_estack_compiling;
10180     cmdmod.cmod_flags =	save_cmod_flags;
10181     if (do_estack_push)
10182 	estack_pop();
10183 
10184     vim_free(line_to_free);
10185     free_imported(&cctx);
10186     free_locals(&cctx);
10187     ga_clear(&cctx.ctx_type_stack);
10188     return ret;
10189 }
10190 
10191     void
10192 set_function_type(ufunc_T *ufunc)
10193 {
10194     int varargs = ufunc->uf_va_name != NULL;
10195     int argcount = ufunc->uf_args.ga_len;
10196 
10197     // Create a type for the function, with the return type and any
10198     // argument types.
10199     // A vararg is included in uf_args.ga_len but not in uf_arg_types.
10200     // The type is included in "tt_args".
10201     if (argcount > 0 || varargs)
10202     {
10203 	if (ufunc->uf_type_list.ga_itemsize == 0)
10204 	    ga_init2(&ufunc->uf_type_list, sizeof(type_T *), 10);
10205 	ufunc->uf_func_type = alloc_func_type(ufunc->uf_ret_type,
10206 					   argcount, &ufunc->uf_type_list);
10207 	// Add argument types to the function type.
10208 	if (func_type_add_arg_types(ufunc->uf_func_type,
10209 				    argcount + varargs,
10210 				    &ufunc->uf_type_list) == FAIL)
10211 	    return;
10212 	ufunc->uf_func_type->tt_argcount = argcount + varargs;
10213 	ufunc->uf_func_type->tt_min_argcount =
10214 				      argcount - ufunc->uf_def_args.ga_len;
10215 	if (ufunc->uf_arg_types == NULL)
10216 	{
10217 	    int i;
10218 
10219 	    // lambda does not have argument types.
10220 	    for (i = 0; i < argcount; ++i)
10221 		ufunc->uf_func_type->tt_args[i] = &t_any;
10222 	}
10223 	else
10224 	    mch_memmove(ufunc->uf_func_type->tt_args,
10225 			 ufunc->uf_arg_types, sizeof(type_T *) * argcount);
10226 	if (varargs)
10227 	{
10228 	    ufunc->uf_func_type->tt_args[argcount] =
10229 		   ufunc->uf_va_type == NULL ? &t_list_any : ufunc->uf_va_type;
10230 	    ufunc->uf_func_type->tt_flags = TTFLAG_VARARGS;
10231 	}
10232     }
10233     else
10234 	// No arguments, can use a predefined type.
10235 	ufunc->uf_func_type = get_func_type(ufunc->uf_ret_type,
10236 					   argcount, &ufunc->uf_type_list);
10237 }
10238 
10239 
10240 /*
10241  * Delete an instruction, free what it contains.
10242  */
10243     void
10244 delete_instr(isn_T *isn)
10245 {
10246     switch (isn->isn_type)
10247     {
10248 	case ISN_DEF:
10249 	case ISN_EXEC:
10250 	case ISN_EXEC_SPLIT:
10251 	case ISN_LEGACY_EVAL:
10252 	case ISN_LOADAUTO:
10253 	case ISN_LOADB:
10254 	case ISN_LOADENV:
10255 	case ISN_LOADG:
10256 	case ISN_LOADOPT:
10257 	case ISN_LOADT:
10258 	case ISN_LOADW:
10259 	case ISN_LOCKUNLOCK:
10260 	case ISN_PUSHEXC:
10261 	case ISN_PUSHFUNC:
10262 	case ISN_PUSHS:
10263 	case ISN_RANGE:
10264 	case ISN_STOREAUTO:
10265 	case ISN_STOREB:
10266 	case ISN_STOREENV:
10267 	case ISN_STOREG:
10268 	case ISN_STORET:
10269 	case ISN_STOREW:
10270 	case ISN_STRINGMEMBER:
10271 	    vim_free(isn->isn_arg.string);
10272 	    break;
10273 
10274 	case ISN_SUBSTITUTE:
10275 	    {
10276 		int	idx;
10277 		isn_T	*list = isn->isn_arg.subs.subs_instr;
10278 
10279 		vim_free(isn->isn_arg.subs.subs_cmd);
10280 		for (idx = 0; list[idx].isn_type != ISN_FINISH; ++idx)
10281 		    delete_instr(list + idx);
10282 		vim_free(list);
10283 	    }
10284 	    break;
10285 
10286 	case ISN_INSTR:
10287 	    {
10288 		int	idx;
10289 		isn_T	*list = isn->isn_arg.instr;
10290 
10291 		for (idx = 0; list[idx].isn_type != ISN_FINISH; ++idx)
10292 		    delete_instr(list + idx);
10293 		vim_free(list);
10294 	    }
10295 	    break;
10296 
10297 	case ISN_LOADS:
10298 	case ISN_STORES:
10299 	    vim_free(isn->isn_arg.loadstore.ls_name);
10300 	    break;
10301 
10302 	case ISN_UNLET:
10303 	case ISN_UNLETENV:
10304 	    vim_free(isn->isn_arg.unlet.ul_name);
10305 	    break;
10306 
10307 	case ISN_STOREOPT:
10308 	    vim_free(isn->isn_arg.storeopt.so_name);
10309 	    break;
10310 
10311 	case ISN_PUSHBLOB:   // push blob isn_arg.blob
10312 	    blob_unref(isn->isn_arg.blob);
10313 	    break;
10314 
10315 	case ISN_PUSHJOB:
10316 #ifdef FEAT_JOB_CHANNEL
10317 	    job_unref(isn->isn_arg.job);
10318 #endif
10319 	    break;
10320 
10321 	case ISN_PUSHCHANNEL:
10322 #ifdef FEAT_JOB_CHANNEL
10323 	    channel_unref(isn->isn_arg.channel);
10324 #endif
10325 	    break;
10326 
10327 	case ISN_UCALL:
10328 	    vim_free(isn->isn_arg.ufunc.cuf_name);
10329 	    break;
10330 
10331 	case ISN_FUNCREF:
10332 	    {
10333 		dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
10334 					       + isn->isn_arg.funcref.fr_func;
10335 		ufunc_T *ufunc = dfunc->df_ufunc;
10336 
10337 		if (ufunc != NULL && func_name_refcount(ufunc->uf_name))
10338 		    func_ptr_unref(ufunc);
10339 	    }
10340 	    break;
10341 
10342 	case ISN_DCALL:
10343 	    {
10344 		dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
10345 					       + isn->isn_arg.dfunc.cdf_idx;
10346 
10347 		if (dfunc->df_ufunc != NULL
10348 			       && func_name_refcount(dfunc->df_ufunc->uf_name))
10349 		    func_ptr_unref(dfunc->df_ufunc);
10350 	    }
10351 	    break;
10352 
10353 	case ISN_NEWFUNC:
10354 	    {
10355 		char_u  *lambda = isn->isn_arg.newfunc.nf_lambda;
10356 		ufunc_T *ufunc = find_func_even_dead(lambda, TRUE, NULL);
10357 
10358 		if (ufunc != NULL)
10359 		{
10360 		    unlink_def_function(ufunc);
10361 		    func_ptr_unref(ufunc);
10362 		}
10363 
10364 		vim_free(lambda);
10365 		vim_free(isn->isn_arg.newfunc.nf_global);
10366 	    }
10367 	    break;
10368 
10369 	case ISN_CHECKTYPE:
10370 	case ISN_SETTYPE:
10371 	    free_type(isn->isn_arg.type.ct_type);
10372 	    break;
10373 
10374 	case ISN_CMDMOD:
10375 	    vim_regfree(isn->isn_arg.cmdmod.cf_cmdmod
10376 					       ->cmod_filter_regmatch.regprog);
10377 	    vim_free(isn->isn_arg.cmdmod.cf_cmdmod);
10378 	    break;
10379 
10380 	case ISN_LOADSCRIPT:
10381 	case ISN_STORESCRIPT:
10382 	    vim_free(isn->isn_arg.script.scriptref);
10383 	    break;
10384 
10385 	case ISN_TRY:
10386 	    vim_free(isn->isn_arg.try.try_ref);
10387 	    break;
10388 
10389 	case ISN_CEXPR_CORE:
10390 	    vim_free(isn->isn_arg.cexpr.cexpr_ref->cer_cmdline);
10391 	    vim_free(isn->isn_arg.cexpr.cexpr_ref);
10392 	    break;
10393 
10394 	case ISN_2BOOL:
10395 	case ISN_2STRING:
10396 	case ISN_2STRING_ANY:
10397 	case ISN_ADDBLOB:
10398 	case ISN_ADDLIST:
10399 	case ISN_ANYINDEX:
10400 	case ISN_ANYSLICE:
10401 	case ISN_BCALL:
10402 	case ISN_BLOBAPPEND:
10403 	case ISN_BLOBINDEX:
10404 	case ISN_BLOBSLICE:
10405 	case ISN_CATCH:
10406 	case ISN_CEXPR_AUCMD:
10407 	case ISN_CHECKLEN:
10408 	case ISN_CHECKNR:
10409 	case ISN_CMDMOD_REV:
10410 	case ISN_COMPAREANY:
10411 	case ISN_COMPAREBLOB:
10412 	case ISN_COMPAREBOOL:
10413 	case ISN_COMPAREDICT:
10414 	case ISN_COMPAREFLOAT:
10415 	case ISN_COMPAREFUNC:
10416 	case ISN_COMPARELIST:
10417 	case ISN_COMPARENR:
10418 	case ISN_COMPARESPECIAL:
10419 	case ISN_COMPARESTRING:
10420 	case ISN_CONCAT:
10421 	case ISN_COND2BOOL:
10422 	case ISN_DEBUG:
10423 	case ISN_DROP:
10424 	case ISN_ECHO:
10425 	case ISN_ECHOCONSOLE:
10426 	case ISN_ECHOERR:
10427 	case ISN_ECHOMSG:
10428 	case ISN_ENDTRY:
10429 	case ISN_EXECCONCAT:
10430 	case ISN_EXECUTE:
10431 	case ISN_FINALLY:
10432 	case ISN_FINISH:
10433 	case ISN_FOR:
10434 	case ISN_GETITEM:
10435 	case ISN_JUMP:
10436 	case ISN_JUMP_IF_ARG_SET:
10437 	case ISN_LISTAPPEND:
10438 	case ISN_LISTINDEX:
10439 	case ISN_LISTSLICE:
10440 	case ISN_LOAD:
10441 	case ISN_LOADBDICT:
10442 	case ISN_LOADGDICT:
10443 	case ISN_LOADOUTER:
10444 	case ISN_LOADREG:
10445 	case ISN_LOADTDICT:
10446 	case ISN_LOADV:
10447 	case ISN_LOADWDICT:
10448 	case ISN_LOCKCONST:
10449 	case ISN_MEMBER:
10450 	case ISN_NEGATENR:
10451 	case ISN_NEWDICT:
10452 	case ISN_NEWLIST:
10453 	case ISN_OPANY:
10454 	case ISN_OPFLOAT:
10455 	case ISN_OPNR:
10456 	case ISN_PCALL:
10457 	case ISN_PCALL_END:
10458 	case ISN_PROF_END:
10459 	case ISN_PROF_START:
10460 	case ISN_PUSHBOOL:
10461 	case ISN_PUSHF:
10462 	case ISN_PUSHNR:
10463 	case ISN_PUSHSPEC:
10464 	case ISN_PUT:
10465 	case ISN_REDIREND:
10466 	case ISN_REDIRSTART:
10467 	case ISN_RETURN:
10468 	case ISN_RETURN_VOID:
10469 	case ISN_SHUFFLE:
10470 	case ISN_SLICE:
10471 	case ISN_STORE:
10472 	case ISN_STOREINDEX:
10473 	case ISN_STORENR:
10474 	case ISN_STOREOUTER:
10475 	case ISN_STORERANGE:
10476 	case ISN_STOREREG:
10477 	case ISN_STOREV:
10478 	case ISN_STRINDEX:
10479 	case ISN_STRSLICE:
10480 	case ISN_THROW:
10481 	case ISN_TRYCONT:
10482 	case ISN_UNLETINDEX:
10483 	case ISN_UNLETRANGE:
10484 	case ISN_UNPACK:
10485 	    // nothing allocated
10486 	    break;
10487     }
10488 }
10489 
10490 /*
10491  * Free all instructions for "dfunc" except df_name.
10492  */
10493     static void
10494 delete_def_function_contents(dfunc_T *dfunc, int mark_deleted)
10495 {
10496     int idx;
10497 
10498     ga_clear(&dfunc->df_def_args_isn);
10499     ga_clear_strings(&dfunc->df_var_names);
10500 
10501     if (dfunc->df_instr != NULL)
10502     {
10503 	for (idx = 0; idx < dfunc->df_instr_count; ++idx)
10504 	    delete_instr(dfunc->df_instr + idx);
10505 	VIM_CLEAR(dfunc->df_instr);
10506 	dfunc->df_instr = NULL;
10507     }
10508     if (dfunc->df_instr_debug != NULL)
10509     {
10510 	for (idx = 0; idx < dfunc->df_instr_debug_count; ++idx)
10511 	    delete_instr(dfunc->df_instr_debug + idx);
10512 	VIM_CLEAR(dfunc->df_instr_debug);
10513 	dfunc->df_instr_debug = NULL;
10514     }
10515 #ifdef FEAT_PROFILE
10516     if (dfunc->df_instr_prof != NULL)
10517     {
10518 	for (idx = 0; idx < dfunc->df_instr_prof_count; ++idx)
10519 	    delete_instr(dfunc->df_instr_prof + idx);
10520 	VIM_CLEAR(dfunc->df_instr_prof);
10521 	dfunc->df_instr_prof = NULL;
10522     }
10523 #endif
10524 
10525     if (mark_deleted)
10526 	dfunc->df_deleted = TRUE;
10527     if (dfunc->df_ufunc != NULL)
10528 	dfunc->df_ufunc->uf_def_status = UF_NOT_COMPILED;
10529 }
10530 
10531 /*
10532  * When a user function is deleted, clear the contents of any associated def
10533  * function, unless another user function still uses it.
10534  * The position in def_functions can be re-used.
10535  */
10536     void
10537 unlink_def_function(ufunc_T *ufunc)
10538 {
10539     if (ufunc->uf_dfunc_idx > 0)
10540     {
10541 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
10542 							 + ufunc->uf_dfunc_idx;
10543 
10544 	if (--dfunc->df_refcount <= 0)
10545 	    delete_def_function_contents(dfunc, TRUE);
10546 	ufunc->uf_def_status = UF_NOT_COMPILED;
10547 	ufunc->uf_dfunc_idx = 0;
10548 	if (dfunc->df_ufunc == ufunc)
10549 	    dfunc->df_ufunc = NULL;
10550     }
10551 }
10552 
10553 /*
10554  * Used when a user function refers to an existing dfunc.
10555  */
10556     void
10557 link_def_function(ufunc_T *ufunc)
10558 {
10559     if (ufunc->uf_dfunc_idx > 0)
10560     {
10561 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
10562 							 + ufunc->uf_dfunc_idx;
10563 
10564 	++dfunc->df_refcount;
10565     }
10566 }
10567 
10568 #if defined(EXITFREE) || defined(PROTO)
10569 /*
10570  * Free all functions defined with ":def".
10571  */
10572     void
10573 free_def_functions(void)
10574 {
10575     int idx;
10576 
10577     for (idx = 0; idx < def_functions.ga_len; ++idx)
10578     {
10579 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data) + idx;
10580 
10581 	delete_def_function_contents(dfunc, TRUE);
10582 	vim_free(dfunc->df_name);
10583     }
10584 
10585     ga_clear(&def_functions);
10586 }
10587 #endif
10588 
10589 
10590 #endif // FEAT_EVAL
10591