xref: /vim-8.2.3635/src/vim9compile.c (revision bd77aa92)
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     static int
694 generate_add_instr(
695 	cctx_T *cctx,
696 	vartype_T vartype,
697 	type_T *type1,
698 	type_T *type2)
699 {
700     garray_T	*stack = &cctx->ctx_type_stack;
701     isn_T	*isn = generate_instr_drop(cctx,
702 		      vartype == VAR_NUMBER ? ISN_OPNR
703 		    : vartype == VAR_LIST ? ISN_ADDLIST
704 		    : vartype == VAR_BLOB ? ISN_ADDBLOB
705 #ifdef FEAT_FLOAT
706 		    : vartype == VAR_FLOAT ? ISN_OPFLOAT
707 #endif
708 		    : ISN_OPANY, 1);
709 
710     if (vartype != VAR_LIST && vartype != VAR_BLOB
711 	    && type1->tt_type != VAR_ANY
712 	    && type2->tt_type != VAR_ANY
713 	    && check_number_or_float(
714 			type1->tt_type, type2->tt_type, (char_u *)"+") == FAIL)
715 	return FAIL;
716 
717     if (isn != NULL)
718 	isn->isn_arg.op.op_type = EXPR_ADD;
719 
720     // When concatenating two lists with different member types the member type
721     // becomes "any".
722     if (vartype == VAR_LIST
723 	    && type1->tt_type == VAR_LIST && type2->tt_type == VAR_LIST
724 	    && type1->tt_member != type2->tt_member)
725 	(((type_T **)stack->ga_data)[stack->ga_len - 1]) = &t_list_any;
726 
727     return isn == NULL ? FAIL : OK;
728 }
729 
730 /*
731  * Get the type to use for an instruction for an operation on "type1" and
732  * "type2".  If they are matching use a type-specific instruction. Otherwise
733  * fall back to runtime type checking.
734  */
735     static vartype_T
736 operator_type(type_T *type1, type_T *type2)
737 {
738     if (type1->tt_type == type2->tt_type
739 	    && (type1->tt_type == VAR_NUMBER
740 		|| type1->tt_type == VAR_LIST
741 #ifdef FEAT_FLOAT
742 		|| type1->tt_type == VAR_FLOAT
743 #endif
744 		|| type1->tt_type == VAR_BLOB))
745 	return type1->tt_type;
746     return VAR_ANY;
747 }
748 
749 /*
750  * Generate an instruction with two arguments.  The instruction depends on the
751  * type of the arguments.
752  */
753     static int
754 generate_two_op(cctx_T *cctx, char_u *op)
755 {
756     garray_T	*stack = &cctx->ctx_type_stack;
757     type_T	*type1;
758     type_T	*type2;
759     vartype_T	vartype;
760     isn_T	*isn;
761 
762     RETURN_OK_IF_SKIP(cctx);
763 
764     // Get the known type of the two items on the stack.
765     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2];
766     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1];
767     vartype = operator_type(type1, type2);
768 
769     switch (*op)
770     {
771 	case '+':
772 		  if (generate_add_instr(cctx, vartype, type1, type2) == FAIL)
773 		      return FAIL;
774 		  break;
775 
776 	case '-':
777 	case '*':
778 	case '/': if (check_number_or_float(type1->tt_type, type2->tt_type,
779 								   op) == FAIL)
780 		      return FAIL;
781 		  if (vartype == VAR_NUMBER)
782 		      isn = generate_instr_drop(cctx, ISN_OPNR, 1);
783 #ifdef FEAT_FLOAT
784 		  else if (vartype == VAR_FLOAT)
785 		      isn = generate_instr_drop(cctx, ISN_OPFLOAT, 1);
786 #endif
787 		  else
788 		      isn = generate_instr_drop(cctx, ISN_OPANY, 1);
789 		  if (isn != NULL)
790 		      isn->isn_arg.op.op_type = *op == '*'
791 				 ? EXPR_MULT : *op == '/'? EXPR_DIV : EXPR_SUB;
792 		  break;
793 
794 	case '%': if ((type1->tt_type != VAR_ANY
795 					       && type1->tt_type != VAR_NUMBER)
796 			  || (type2->tt_type != VAR_ANY
797 					      && type2->tt_type != VAR_NUMBER))
798 		  {
799 		      emsg(_(e_percent_requires_number_arguments));
800 		      return FAIL;
801 		  }
802 		  isn = generate_instr_drop(cctx,
803 			      vartype == VAR_NUMBER ? ISN_OPNR : ISN_OPANY, 1);
804 		  if (isn != NULL)
805 		      isn->isn_arg.op.op_type = EXPR_REM;
806 		  break;
807     }
808 
809     // correct type of result
810     if (vartype == VAR_ANY)
811     {
812 	type_T *type = &t_any;
813 
814 #ifdef FEAT_FLOAT
815 	// float+number and number+float results in float
816 	if ((type1->tt_type == VAR_NUMBER || type1->tt_type == VAR_FLOAT)
817 		&& (type2->tt_type == VAR_NUMBER || type2->tt_type == VAR_FLOAT))
818 	    type = &t_float;
819 #endif
820 	((type_T **)stack->ga_data)[stack->ga_len - 1] = type;
821     }
822 
823     return OK;
824 }
825 
826 /*
827  * Get the instruction to use for comparing "type1" with "type2"
828  * Return ISN_DROP when failed.
829  */
830     static isntype_T
831 get_compare_isn(exprtype_T exprtype, vartype_T type1, vartype_T type2)
832 {
833     isntype_T	isntype = ISN_DROP;
834 
835     if (type1 == VAR_UNKNOWN)
836 	type1 = VAR_ANY;
837     if (type2 == VAR_UNKNOWN)
838 	type2 = VAR_ANY;
839 
840     if (type1 == type2)
841     {
842 	switch (type1)
843 	{
844 	    case VAR_BOOL: isntype = ISN_COMPAREBOOL; break;
845 	    case VAR_SPECIAL: isntype = ISN_COMPARESPECIAL; break;
846 	    case VAR_NUMBER: isntype = ISN_COMPARENR; break;
847 	    case VAR_FLOAT: isntype = ISN_COMPAREFLOAT; break;
848 	    case VAR_STRING: isntype = ISN_COMPARESTRING; break;
849 	    case VAR_BLOB: isntype = ISN_COMPAREBLOB; break;
850 	    case VAR_LIST: isntype = ISN_COMPARELIST; break;
851 	    case VAR_DICT: isntype = ISN_COMPAREDICT; break;
852 	    case VAR_FUNC: isntype = ISN_COMPAREFUNC; break;
853 	    default: isntype = ISN_COMPAREANY; break;
854 	}
855     }
856     else if (type1 == VAR_ANY || type2 == VAR_ANY
857 	    || ((type1 == VAR_NUMBER || type1 == VAR_FLOAT)
858 	      && (type2 == VAR_NUMBER || type2 == VAR_FLOAT)))
859 	isntype = ISN_COMPAREANY;
860 
861     if ((exprtype == EXPR_IS || exprtype == EXPR_ISNOT)
862 	    && (isntype == ISN_COMPAREBOOL
863 	    || isntype == ISN_COMPARESPECIAL
864 	    || isntype == ISN_COMPARENR
865 	    || isntype == ISN_COMPAREFLOAT))
866     {
867 	semsg(_(e_cannot_use_str_with_str),
868 		exprtype == EXPR_IS ? "is" : "isnot" , vartype_name(type1));
869 	return ISN_DROP;
870     }
871     if (isntype == ISN_DROP
872 	    || ((exprtype != EXPR_EQUAL && exprtype != EXPR_NEQUAL
873 		    && (type1 == VAR_BOOL || type1 == VAR_SPECIAL
874 		       || type2 == VAR_BOOL || type2 == VAR_SPECIAL)))
875 	    || ((exprtype != EXPR_EQUAL && exprtype != EXPR_NEQUAL
876 				 && exprtype != EXPR_IS && exprtype != EXPR_ISNOT
877 		    && (type1 == VAR_BLOB || type2 == VAR_BLOB
878 			|| type1 == VAR_LIST || type2 == VAR_LIST))))
879     {
880 	semsg(_(e_cannot_compare_str_with_str),
881 		vartype_name(type1), vartype_name(type2));
882 	return ISN_DROP;
883     }
884     return isntype;
885 }
886 
887     int
888 check_compare_types(exprtype_T type, typval_T *tv1, typval_T *tv2)
889 {
890     if (get_compare_isn(type, tv1->v_type, tv2->v_type) == ISN_DROP)
891 	return FAIL;
892     return OK;
893 }
894 
895 /*
896  * Generate an ISN_COMPARE* instruction with a boolean result.
897  */
898     static int
899 generate_COMPARE(cctx_T *cctx, exprtype_T exprtype, int ic)
900 {
901     isntype_T	isntype;
902     isn_T	*isn;
903     garray_T	*stack = &cctx->ctx_type_stack;
904     vartype_T	type1;
905     vartype_T	type2;
906 
907     RETURN_OK_IF_SKIP(cctx);
908 
909     // Get the known type of the two items on the stack.  If they are matching
910     // use a type-specific instruction. Otherwise fall back to runtime type
911     // checking.
912     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2]->tt_type;
913     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1]->tt_type;
914     isntype = get_compare_isn(exprtype, type1, type2);
915     if (isntype == ISN_DROP)
916 	return FAIL;
917 
918     if ((isn = generate_instr(cctx, isntype)) == NULL)
919 	return FAIL;
920     isn->isn_arg.op.op_type = exprtype;
921     isn->isn_arg.op.op_ic = ic;
922 
923     // takes two arguments, puts one bool back
924     if (stack->ga_len >= 2)
925     {
926 	--stack->ga_len;
927 	((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_bool;
928     }
929 
930     return OK;
931 }
932 
933 /*
934  * Generate an ISN_2BOOL instruction.
935  * "offset" is the offset in the type stack.
936  */
937     static int
938 generate_2BOOL(cctx_T *cctx, int invert, int offset)
939 {
940     isn_T	*isn;
941     garray_T	*stack = &cctx->ctx_type_stack;
942 
943     RETURN_OK_IF_SKIP(cctx);
944     if ((isn = generate_instr(cctx, ISN_2BOOL)) == NULL)
945 	return FAIL;
946     isn->isn_arg.tobool.invert = invert;
947     isn->isn_arg.tobool.offset = offset;
948 
949     // type becomes bool
950     ((type_T **)stack->ga_data)[stack->ga_len + offset] = &t_bool;
951 
952     return OK;
953 }
954 
955 /*
956  * Generate an ISN_COND2BOOL instruction.
957  */
958     static int
959 generate_COND2BOOL(cctx_T *cctx)
960 {
961     isn_T	*isn;
962     garray_T	*stack = &cctx->ctx_type_stack;
963 
964     RETURN_OK_IF_SKIP(cctx);
965     if ((isn = generate_instr(cctx, ISN_COND2BOOL)) == NULL)
966 	return FAIL;
967 
968     // type becomes bool
969     ((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_bool;
970 
971     return OK;
972 }
973 
974     static int
975 generate_TYPECHECK(
976 	cctx_T	    *cctx,
977 	type_T	    *expected,
978 	int	    offset,
979 	int	    argidx)
980 {
981     isn_T	*isn;
982     garray_T	*stack = &cctx->ctx_type_stack;
983 
984     RETURN_OK_IF_SKIP(cctx);
985     if ((isn = generate_instr(cctx, ISN_CHECKTYPE)) == NULL)
986 	return FAIL;
987     isn->isn_arg.type.ct_type = alloc_type(expected);
988     isn->isn_arg.type.ct_off = (int8_T)offset;
989     isn->isn_arg.type.ct_arg_idx = (int8_T)argidx;
990 
991     // type becomes expected
992     ((type_T **)stack->ga_data)[stack->ga_len + offset] = expected;
993 
994     return OK;
995 }
996 
997     static int
998 generate_SETTYPE(
999 	cctx_T	    *cctx,
1000 	type_T	    *expected)
1001 {
1002     isn_T	*isn;
1003 
1004     RETURN_OK_IF_SKIP(cctx);
1005     if ((isn = generate_instr(cctx, ISN_SETTYPE)) == NULL)
1006 	return FAIL;
1007     isn->isn_arg.type.ct_type = alloc_type(expected);
1008     return OK;
1009 }
1010 
1011 /*
1012  * Return TRUE if "actual" could be "expected" and a runtime typecheck is to be
1013  * used.  Return FALSE if the types will never match.
1014  */
1015     static int
1016 use_typecheck(type_T *actual, type_T *expected)
1017 {
1018     if (actual->tt_type == VAR_ANY
1019 	    || actual->tt_type == VAR_UNKNOWN
1020 	    || (actual->tt_type == VAR_FUNC
1021 		&& (expected->tt_type == VAR_FUNC
1022 					   || expected->tt_type == VAR_PARTIAL)
1023 		&& (actual->tt_member == &t_any || actual->tt_argcount < 0)
1024 		&& ((actual->tt_member == &t_void)
1025 					 == (expected->tt_member == &t_void))))
1026 	return TRUE;
1027     if ((actual->tt_type == VAR_LIST || actual->tt_type == VAR_DICT)
1028 				       && actual->tt_type == expected->tt_type)
1029 	// This takes care of a nested list or dict.
1030 	return use_typecheck(actual->tt_member, expected->tt_member);
1031     return FALSE;
1032 }
1033 
1034 /*
1035  * Check that
1036  * - "actual" matches "expected" type or
1037  * - "actual" is a type that can be "expected" type: add a runtime check; or
1038  * - return FAIL.
1039  * If "actual_is_const" is TRUE then the type won't change at runtime, do not
1040  * generate a TYPECHECK.
1041  */
1042     static int
1043 need_type_where(
1044 	type_T	*actual,
1045 	type_T	*expected,
1046 	int	offset,
1047 	where_T	where,
1048 	cctx_T	*cctx,
1049 	int	silent,
1050 	int	actual_is_const)
1051 {
1052     if (expected == &t_bool && actual != &t_bool
1053 					&& (actual->tt_flags & TTFLAG_BOOL_OK))
1054     {
1055 	// Using "0", "1" or the result of an expression with "&&" or "||" as a
1056 	// boolean is OK but requires a conversion.
1057 	generate_2BOOL(cctx, FALSE, offset);
1058 	return OK;
1059     }
1060 
1061     if (check_type(expected, actual, FALSE, where) == OK)
1062 	return OK;
1063 
1064     // If the actual type can be the expected type add a runtime check.
1065     // If it's a constant a runtime check makes no sense.
1066     if ((!actual_is_const || actual == &t_any)
1067 					    && use_typecheck(actual, expected))
1068     {
1069 	generate_TYPECHECK(cctx, expected, offset, where.wt_index);
1070 	return OK;
1071     }
1072 
1073     if (!silent)
1074 	type_mismatch_where(expected, actual, where);
1075     return FAIL;
1076 }
1077 
1078     int
1079 need_type(
1080 	type_T	*actual,
1081 	type_T	*expected,
1082 	int	offset,
1083 	int	arg_idx,
1084 	cctx_T	*cctx,
1085 	int	silent,
1086 	int	actual_is_const)
1087 {
1088     where_T where = WHERE_INIT;
1089 
1090     where.wt_index = arg_idx;
1091     return need_type_where(actual, expected, offset, where,
1092 						cctx, silent, actual_is_const);
1093 }
1094 
1095 /*
1096  * Check that the top of the type stack has a type that can be used as a
1097  * condition.  Give an error and return FAIL if not.
1098  */
1099     static int
1100 bool_on_stack(cctx_T *cctx)
1101 {
1102     garray_T	*stack = &cctx->ctx_type_stack;
1103     type_T	*type;
1104 
1105     type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1106     if (type == &t_bool)
1107 	return OK;
1108 
1109     if (type == &t_any || type == &t_number || type == &t_number_bool)
1110 	// Number 0 and 1 are OK to use as a bool.  "any" could also be a bool.
1111 	// This requires a runtime type check.
1112 	return generate_COND2BOOL(cctx);
1113 
1114     return need_type(type, &t_bool, -1, 0, cctx, FALSE, FALSE);
1115 }
1116 
1117 /*
1118  * Generate an ISN_PUSHNR instruction.
1119  */
1120     static int
1121 generate_PUSHNR(cctx_T *cctx, varnumber_T number)
1122 {
1123     isn_T	*isn;
1124     garray_T	*stack = &cctx->ctx_type_stack;
1125 
1126     RETURN_OK_IF_SKIP(cctx);
1127     if ((isn = generate_instr_type(cctx, ISN_PUSHNR, &t_number)) == NULL)
1128 	return FAIL;
1129     isn->isn_arg.number = number;
1130 
1131     if (number == 0 || number == 1)
1132 	// A 0 or 1 number can also be used as a bool.
1133 	((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_number_bool;
1134     return OK;
1135 }
1136 
1137 /*
1138  * Generate an ISN_PUSHBOOL instruction.
1139  */
1140     static int
1141 generate_PUSHBOOL(cctx_T *cctx, varnumber_T number)
1142 {
1143     isn_T	*isn;
1144 
1145     RETURN_OK_IF_SKIP(cctx);
1146     if ((isn = generate_instr_type(cctx, ISN_PUSHBOOL, &t_bool)) == NULL)
1147 	return FAIL;
1148     isn->isn_arg.number = number;
1149 
1150     return OK;
1151 }
1152 
1153 /*
1154  * Generate an ISN_PUSHSPEC instruction.
1155  */
1156     static int
1157 generate_PUSHSPEC(cctx_T *cctx, varnumber_T number)
1158 {
1159     isn_T	*isn;
1160 
1161     RETURN_OK_IF_SKIP(cctx);
1162     if ((isn = generate_instr_type(cctx, ISN_PUSHSPEC, &t_special)) == NULL)
1163 	return FAIL;
1164     isn->isn_arg.number = number;
1165 
1166     return OK;
1167 }
1168 
1169 #ifdef FEAT_FLOAT
1170 /*
1171  * Generate an ISN_PUSHF instruction.
1172  */
1173     static int
1174 generate_PUSHF(cctx_T *cctx, float_T fnumber)
1175 {
1176     isn_T	*isn;
1177 
1178     RETURN_OK_IF_SKIP(cctx);
1179     if ((isn = generate_instr_type(cctx, ISN_PUSHF, &t_float)) == NULL)
1180 	return FAIL;
1181     isn->isn_arg.fnumber = fnumber;
1182 
1183     return OK;
1184 }
1185 #endif
1186 
1187 /*
1188  * Generate an ISN_PUSHS instruction.
1189  * Consumes "*str".  When freed *str is set to NULL, unless "str" is NULL.
1190  */
1191     static int
1192 generate_PUSHS(cctx_T *cctx, char_u **str)
1193 {
1194     isn_T	*isn;
1195 
1196     if (cctx->ctx_skip == SKIP_YES)
1197     {
1198 	if (str != NULL)
1199 	    VIM_CLEAR(*str);
1200 	return OK;
1201     }
1202     if ((isn = generate_instr_type(cctx, ISN_PUSHS, &t_string)) == NULL)
1203     {
1204 	if (str != NULL)
1205 	    VIM_CLEAR(*str);
1206 	return FAIL;
1207     }
1208     isn->isn_arg.string = str == NULL ? NULL : *str;
1209 
1210     return OK;
1211 }
1212 
1213 /*
1214  * Generate an ISN_PUSHCHANNEL instruction.
1215  * Consumes "channel".
1216  */
1217     static int
1218 generate_PUSHCHANNEL(cctx_T *cctx, channel_T *channel)
1219 {
1220     isn_T	*isn;
1221 
1222     RETURN_OK_IF_SKIP(cctx);
1223     if ((isn = generate_instr_type(cctx, ISN_PUSHCHANNEL, &t_channel)) == NULL)
1224 	return FAIL;
1225     isn->isn_arg.channel = channel;
1226 
1227     return OK;
1228 }
1229 
1230 /*
1231  * Generate an ISN_PUSHJOB instruction.
1232  * Consumes "job".
1233  */
1234     static int
1235 generate_PUSHJOB(cctx_T *cctx, job_T *job)
1236 {
1237     isn_T	*isn;
1238 
1239     RETURN_OK_IF_SKIP(cctx);
1240     if ((isn = generate_instr_type(cctx, ISN_PUSHJOB, &t_channel)) == NULL)
1241 	return FAIL;
1242     isn->isn_arg.job = job;
1243 
1244     return OK;
1245 }
1246 
1247 /*
1248  * Generate an ISN_PUSHBLOB instruction.
1249  * Consumes "blob".
1250  */
1251     static int
1252 generate_PUSHBLOB(cctx_T *cctx, blob_T *blob)
1253 {
1254     isn_T	*isn;
1255 
1256     RETURN_OK_IF_SKIP(cctx);
1257     if ((isn = generate_instr_type(cctx, ISN_PUSHBLOB, &t_blob)) == NULL)
1258 	return FAIL;
1259     isn->isn_arg.blob = blob;
1260 
1261     return OK;
1262 }
1263 
1264 /*
1265  * Generate an ISN_PUSHFUNC instruction with name "name".
1266  * Consumes "name".
1267  */
1268     static int
1269 generate_PUSHFUNC(cctx_T *cctx, char_u *name, type_T *type)
1270 {
1271     isn_T	*isn;
1272 
1273     RETURN_OK_IF_SKIP(cctx);
1274     if ((isn = generate_instr_type(cctx, ISN_PUSHFUNC, type)) == NULL)
1275 	return FAIL;
1276     isn->isn_arg.string = name == NULL ? NULL : vim_strsave(name);
1277 
1278     return OK;
1279 }
1280 
1281 /*
1282  * Generate an ISN_GETITEM instruction with "index".
1283  * "with_op" is TRUE for "+=" and other operators, the stack has the current
1284  * value below the list with values.
1285  */
1286     static int
1287 generate_GETITEM(cctx_T *cctx, int index, int with_op)
1288 {
1289     isn_T	*isn;
1290     garray_T	*stack = &cctx->ctx_type_stack;
1291     type_T	*type = ((type_T **)stack->ga_data)[stack->ga_len
1292 							  - (with_op ? 2 : 1)];
1293     type_T	*item_type = &t_any;
1294 
1295     RETURN_OK_IF_SKIP(cctx);
1296 
1297     if (type->tt_type != VAR_LIST)
1298     {
1299 	// cannot happen, caller has checked the type
1300 	emsg(_(e_listreq));
1301 	return FAIL;
1302     }
1303     item_type = type->tt_member;
1304     if ((isn = generate_instr(cctx, ISN_GETITEM)) == NULL)
1305 	return FAIL;
1306     isn->isn_arg.getitem.gi_index = index;
1307     isn->isn_arg.getitem.gi_with_op = with_op;
1308 
1309     // add the item type to the type stack
1310     if (GA_GROW_FAILS(stack, 1))
1311 	return FAIL;
1312     ((type_T **)stack->ga_data)[stack->ga_len] = item_type;
1313     ++stack->ga_len;
1314     return OK;
1315 }
1316 
1317 /*
1318  * Generate an ISN_SLICE instruction with "count".
1319  */
1320     static int
1321 generate_SLICE(cctx_T *cctx, int count)
1322 {
1323     isn_T	*isn;
1324 
1325     RETURN_OK_IF_SKIP(cctx);
1326     if ((isn = generate_instr(cctx, ISN_SLICE)) == NULL)
1327 	return FAIL;
1328     isn->isn_arg.number = count;
1329     return OK;
1330 }
1331 
1332 /*
1333  * Generate an ISN_CHECKLEN instruction with "min_len".
1334  */
1335     static int
1336 generate_CHECKLEN(cctx_T *cctx, int min_len, int more_OK)
1337 {
1338     isn_T	*isn;
1339 
1340     RETURN_OK_IF_SKIP(cctx);
1341 
1342     if ((isn = generate_instr(cctx, ISN_CHECKLEN)) == NULL)
1343 	return FAIL;
1344     isn->isn_arg.checklen.cl_min_len = min_len;
1345     isn->isn_arg.checklen.cl_more_OK = more_OK;
1346 
1347     return OK;
1348 }
1349 
1350 /*
1351  * Generate an ISN_STORE instruction.
1352  */
1353     static int
1354 generate_STORE(cctx_T *cctx, isntype_T isn_type, int idx, char_u *name)
1355 {
1356     isn_T	*isn;
1357 
1358     RETURN_OK_IF_SKIP(cctx);
1359     if ((isn = generate_instr_drop(cctx, isn_type, 1)) == NULL)
1360 	return FAIL;
1361     if (name != NULL)
1362 	isn->isn_arg.string = vim_strsave(name);
1363     else
1364 	isn->isn_arg.number = idx;
1365 
1366     return OK;
1367 }
1368 
1369 /*
1370  * Generate an ISN_STOREOUTER instruction.
1371  */
1372     static int
1373 generate_STOREOUTER(cctx_T *cctx, int idx, int level)
1374 {
1375     isn_T	*isn;
1376 
1377     RETURN_OK_IF_SKIP(cctx);
1378     if ((isn = generate_instr_drop(cctx, ISN_STOREOUTER, 1)) == NULL)
1379 	return FAIL;
1380     isn->isn_arg.outer.outer_idx = idx;
1381     isn->isn_arg.outer.outer_depth = level;
1382 
1383     return OK;
1384 }
1385 
1386 /*
1387  * Generate an ISN_STORENR instruction (short for ISN_PUSHNR + ISN_STORE)
1388  */
1389     static int
1390 generate_STORENR(cctx_T *cctx, int idx, varnumber_T value)
1391 {
1392     isn_T	*isn;
1393 
1394     RETURN_OK_IF_SKIP(cctx);
1395     if ((isn = generate_instr(cctx, ISN_STORENR)) == NULL)
1396 	return FAIL;
1397     isn->isn_arg.storenr.stnr_idx = idx;
1398     isn->isn_arg.storenr.stnr_val = value;
1399 
1400     return OK;
1401 }
1402 
1403 /*
1404  * Generate an ISN_STOREOPT instruction
1405  */
1406     static int
1407 generate_STOREOPT(cctx_T *cctx, char_u *name, int opt_flags)
1408 {
1409     isn_T	*isn;
1410 
1411     RETURN_OK_IF_SKIP(cctx);
1412     if ((isn = generate_instr_drop(cctx, ISN_STOREOPT, 1)) == NULL)
1413 	return FAIL;
1414     isn->isn_arg.storeopt.so_name = vim_strsave(name);
1415     isn->isn_arg.storeopt.so_flags = opt_flags;
1416 
1417     return OK;
1418 }
1419 
1420 /*
1421  * Generate an ISN_LOAD or similar instruction.
1422  */
1423     static int
1424 generate_LOAD(
1425 	cctx_T	    *cctx,
1426 	isntype_T   isn_type,
1427 	int	    idx,
1428 	char_u	    *name,
1429 	type_T	    *type)
1430 {
1431     isn_T	*isn;
1432 
1433     RETURN_OK_IF_SKIP(cctx);
1434     if ((isn = generate_instr_type(cctx, isn_type, type)) == NULL)
1435 	return FAIL;
1436     if (name != NULL)
1437 	isn->isn_arg.string = vim_strsave(name);
1438     else
1439 	isn->isn_arg.number = idx;
1440 
1441     return OK;
1442 }
1443 
1444 /*
1445  * Generate an ISN_LOADOUTER instruction
1446  */
1447     static int
1448 generate_LOADOUTER(
1449 	cctx_T	    *cctx,
1450 	int	    idx,
1451 	int	    nesting,
1452 	type_T	    *type)
1453 {
1454     isn_T	*isn;
1455 
1456     RETURN_OK_IF_SKIP(cctx);
1457     if ((isn = generate_instr_type(cctx, ISN_LOADOUTER, type)) == NULL)
1458 	return FAIL;
1459     isn->isn_arg.outer.outer_idx = idx;
1460     isn->isn_arg.outer.outer_depth = nesting;
1461 
1462     return OK;
1463 }
1464 
1465 /*
1466  * Generate an ISN_LOADV instruction for v:var.
1467  */
1468     static int
1469 generate_LOADV(
1470 	cctx_T	    *cctx,
1471 	char_u	    *name,
1472 	int	    error)
1473 {
1474     int	    di_flags;
1475     int	    vidx = find_vim_var(name, &di_flags);
1476     type_T  *type;
1477 
1478     RETURN_OK_IF_SKIP(cctx);
1479     if (vidx < 0)
1480     {
1481 	if (error)
1482 	    semsg(_(e_variable_not_found_str), name);
1483 	return FAIL;
1484     }
1485     type = typval2type_vimvar(get_vim_var_tv(vidx), cctx->ctx_type_list);
1486 
1487     return generate_LOAD(cctx, ISN_LOADV, vidx, NULL, type);
1488 }
1489 
1490 /*
1491  * Generate an ISN_UNLET instruction.
1492  */
1493     static int
1494 generate_UNLET(cctx_T *cctx, isntype_T isn_type, char_u *name, int forceit)
1495 {
1496     isn_T	*isn;
1497 
1498     RETURN_OK_IF_SKIP(cctx);
1499     if ((isn = generate_instr(cctx, isn_type)) == NULL)
1500 	return FAIL;
1501     isn->isn_arg.unlet.ul_name = vim_strsave(name);
1502     isn->isn_arg.unlet.ul_forceit = forceit;
1503 
1504     return OK;
1505 }
1506 
1507 /*
1508  * Generate an ISN_LOCKCONST instruction.
1509  */
1510     static int
1511 generate_LOCKCONST(cctx_T *cctx)
1512 {
1513     isn_T	*isn;
1514 
1515     RETURN_OK_IF_SKIP(cctx);
1516     if ((isn = generate_instr(cctx, ISN_LOCKCONST)) == NULL)
1517 	return FAIL;
1518     return OK;
1519 }
1520 
1521 /*
1522  * Generate an ISN_LOADS instruction.
1523  */
1524     static int
1525 generate_OLDSCRIPT(
1526 	cctx_T	    *cctx,
1527 	isntype_T   isn_type,
1528 	char_u	    *name,
1529 	int	    sid,
1530 	type_T	    *type)
1531 {
1532     isn_T	*isn;
1533 
1534     RETURN_OK_IF_SKIP(cctx);
1535     if (isn_type == ISN_LOADS)
1536 	isn = generate_instr_type(cctx, isn_type, type);
1537     else
1538 	isn = generate_instr_drop(cctx, isn_type, 1);
1539     if (isn == NULL)
1540 	return FAIL;
1541     isn->isn_arg.loadstore.ls_name = vim_strsave(name);
1542     isn->isn_arg.loadstore.ls_sid = sid;
1543 
1544     return OK;
1545 }
1546 
1547 /*
1548  * Generate an ISN_LOADSCRIPT or ISN_STORESCRIPT instruction.
1549  */
1550     static int
1551 generate_VIM9SCRIPT(
1552 	cctx_T	    *cctx,
1553 	isntype_T   isn_type,
1554 	int	    sid,
1555 	int	    idx,
1556 	type_T	    *type)
1557 {
1558     isn_T	*isn;
1559     scriptref_T	*sref;
1560     scriptitem_T *si = SCRIPT_ITEM(sid);
1561 
1562     RETURN_OK_IF_SKIP(cctx);
1563     if (isn_type == ISN_LOADSCRIPT)
1564 	isn = generate_instr_type(cctx, isn_type, type);
1565     else
1566 	isn = generate_instr_drop(cctx, isn_type, 1);
1567     if (isn == NULL)
1568 	return FAIL;
1569 
1570     // This requires three arguments, which doesn't fit in an instruction, thus
1571     // we need to allocate a struct for this.
1572     sref = ALLOC_ONE(scriptref_T);
1573     if (sref == NULL)
1574 	return FAIL;
1575     isn->isn_arg.script.scriptref = sref;
1576     sref->sref_sid = sid;
1577     sref->sref_idx = idx;
1578     sref->sref_seq = si->sn_script_seq;
1579     sref->sref_type = type;
1580     return OK;
1581 }
1582 
1583 /*
1584  * Generate an ISN_NEWLIST instruction.
1585  */
1586     static int
1587 generate_NEWLIST(cctx_T *cctx, int count)
1588 {
1589     isn_T	*isn;
1590     garray_T	*stack = &cctx->ctx_type_stack;
1591     type_T	*type;
1592     type_T	*member;
1593 
1594     RETURN_OK_IF_SKIP(cctx);
1595     if ((isn = generate_instr(cctx, ISN_NEWLIST)) == NULL)
1596 	return FAIL;
1597     isn->isn_arg.number = count;
1598 
1599     // get the member type from all the items on the stack.
1600     if (count == 0)
1601 	member = &t_unknown;
1602     else
1603 	member = get_member_type_from_stack(
1604 	    ((type_T **)stack->ga_data) + stack->ga_len, count, 1,
1605 							  cctx->ctx_type_list);
1606     type = get_list_type(member, cctx->ctx_type_list);
1607 
1608     // drop the value types
1609     stack->ga_len -= count;
1610 
1611     // add the list type to the type stack
1612     if (GA_GROW_FAILS(stack, 1))
1613 	return FAIL;
1614     ((type_T **)stack->ga_data)[stack->ga_len] = type;
1615     ++stack->ga_len;
1616 
1617     return OK;
1618 }
1619 
1620 /*
1621  * Generate an ISN_NEWDICT instruction.
1622  */
1623     static int
1624 generate_NEWDICT(cctx_T *cctx, int count)
1625 {
1626     isn_T	*isn;
1627     garray_T	*stack = &cctx->ctx_type_stack;
1628     type_T	*type;
1629     type_T	*member;
1630 
1631     RETURN_OK_IF_SKIP(cctx);
1632     if ((isn = generate_instr(cctx, ISN_NEWDICT)) == NULL)
1633 	return FAIL;
1634     isn->isn_arg.number = count;
1635 
1636     if (count == 0)
1637 	member = &t_void;
1638     else
1639 	member = get_member_type_from_stack(
1640 	    ((type_T **)stack->ga_data) + stack->ga_len, count, 2,
1641 							  cctx->ctx_type_list);
1642     type = get_dict_type(member, cctx->ctx_type_list);
1643 
1644     // drop the key and value types
1645     stack->ga_len -= 2 * count;
1646 
1647     // add the dict type to the type stack
1648     if (GA_GROW_FAILS(stack, 1))
1649 	return FAIL;
1650     ((type_T **)stack->ga_data)[stack->ga_len] = type;
1651     ++stack->ga_len;
1652 
1653     return OK;
1654 }
1655 
1656 /*
1657  * Generate an ISN_FUNCREF instruction.
1658  */
1659     static int
1660 generate_FUNCREF(cctx_T *cctx, ufunc_T *ufunc)
1661 {
1662     isn_T	*isn;
1663     garray_T	*stack = &cctx->ctx_type_stack;
1664 
1665     RETURN_OK_IF_SKIP(cctx);
1666     if ((isn = generate_instr(cctx, ISN_FUNCREF)) == NULL)
1667 	return FAIL;
1668     isn->isn_arg.funcref.fr_func = ufunc->uf_dfunc_idx;
1669     cctx->ctx_has_closure = 1;
1670 
1671     // If the referenced function is a closure, it may use items further up in
1672     // the nested context, including this one.
1673     if (ufunc->uf_flags & FC_CLOSURE)
1674 	cctx->ctx_ufunc->uf_flags |= FC_CLOSURE;
1675 
1676     if (GA_GROW_FAILS(stack, 1))
1677 	return FAIL;
1678     ((type_T **)stack->ga_data)[stack->ga_len] =
1679 	       ufunc->uf_func_type == NULL ? &t_func_any : ufunc->uf_func_type;
1680     ++stack->ga_len;
1681 
1682     return OK;
1683 }
1684 
1685 /*
1686  * Generate an ISN_NEWFUNC instruction.
1687  * "lambda_name" and "func_name" must be in allocated memory and will be
1688  * consumed.
1689  */
1690     static int
1691 generate_NEWFUNC(cctx_T *cctx, char_u *lambda_name, char_u *func_name)
1692 {
1693     isn_T	*isn;
1694 
1695     if (cctx->ctx_skip == SKIP_YES)
1696     {
1697 	vim_free(lambda_name);
1698 	vim_free(func_name);
1699 	return OK;
1700     }
1701     if ((isn = generate_instr(cctx, ISN_NEWFUNC)) == NULL)
1702     {
1703 	vim_free(lambda_name);
1704 	vim_free(func_name);
1705 	return FAIL;
1706     }
1707     isn->isn_arg.newfunc.nf_lambda = lambda_name;
1708     isn->isn_arg.newfunc.nf_global = func_name;
1709 
1710     return OK;
1711 }
1712 
1713 /*
1714  * Generate an ISN_DEF instruction: list functions
1715  */
1716     static int
1717 generate_DEF(cctx_T *cctx, char_u *name, size_t len)
1718 {
1719     isn_T	*isn;
1720 
1721     RETURN_OK_IF_SKIP(cctx);
1722     if ((isn = generate_instr(cctx, ISN_DEF)) == NULL)
1723 	return FAIL;
1724     if (len > 0)
1725     {
1726 	isn->isn_arg.string = vim_strnsave(name, len);
1727 	if (isn->isn_arg.string == NULL)
1728 	    return FAIL;
1729     }
1730     return OK;
1731 }
1732 
1733 /*
1734  * Generate an ISN_JUMP instruction.
1735  */
1736     static int
1737 generate_JUMP(cctx_T *cctx, jumpwhen_T when, int where)
1738 {
1739     isn_T	*isn;
1740     garray_T	*stack = &cctx->ctx_type_stack;
1741 
1742     RETURN_OK_IF_SKIP(cctx);
1743     if ((isn = generate_instr(cctx, ISN_JUMP)) == NULL)
1744 	return FAIL;
1745     isn->isn_arg.jump.jump_when = when;
1746     isn->isn_arg.jump.jump_where = where;
1747 
1748     if (when != JUMP_ALWAYS && stack->ga_len > 0)
1749 	--stack->ga_len;
1750 
1751     return OK;
1752 }
1753 
1754 /*
1755  * Generate an ISN_JUMP_IF_ARG_SET instruction.
1756  */
1757     static int
1758 generate_JUMP_IF_ARG_SET(cctx_T *cctx, int arg_off)
1759 {
1760     isn_T	*isn;
1761 
1762     RETURN_OK_IF_SKIP(cctx);
1763     if ((isn = generate_instr(cctx, ISN_JUMP_IF_ARG_SET)) == NULL)
1764 	return FAIL;
1765     isn->isn_arg.jumparg.jump_arg_off = arg_off;
1766     // jump_where is set later
1767     return OK;
1768 }
1769 
1770     static int
1771 generate_FOR(cctx_T *cctx, int loop_idx)
1772 {
1773     isn_T	*isn;
1774     garray_T	*stack = &cctx->ctx_type_stack;
1775 
1776     RETURN_OK_IF_SKIP(cctx);
1777     if ((isn = generate_instr(cctx, ISN_FOR)) == NULL)
1778 	return FAIL;
1779     isn->isn_arg.forloop.for_idx = loop_idx;
1780 
1781     if (GA_GROW_FAILS(stack, 1))
1782 	return FAIL;
1783     // type doesn't matter, will be stored next
1784     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
1785     ++stack->ga_len;
1786 
1787     return OK;
1788 }
1789 /*
1790  * Generate an ISN_TRYCONT instruction.
1791  */
1792     static int
1793 generate_TRYCONT(cctx_T *cctx, int levels, int where)
1794 {
1795     isn_T	*isn;
1796 
1797     RETURN_OK_IF_SKIP(cctx);
1798     if ((isn = generate_instr(cctx, ISN_TRYCONT)) == NULL)
1799 	return FAIL;
1800     isn->isn_arg.trycont.tct_levels = levels;
1801     isn->isn_arg.trycont.tct_where = where;
1802 
1803     return OK;
1804 }
1805 
1806 
1807 /*
1808  * Generate an ISN_BCALL instruction.
1809  * "method_call" is TRUE for "value->method()"
1810  * Return FAIL if the number of arguments is wrong.
1811  */
1812     static int
1813 generate_BCALL(cctx_T *cctx, int func_idx, int argcount, int method_call)
1814 {
1815     isn_T	*isn;
1816     garray_T	*stack = &cctx->ctx_type_stack;
1817     int		argoff;
1818     type_T	**argtypes = NULL;
1819     type_T	*shuffled_argtypes[MAX_FUNC_ARGS];
1820     type_T	*maptype = NULL;
1821 
1822     RETURN_OK_IF_SKIP(cctx);
1823     argoff = check_internal_func(func_idx, argcount);
1824     if (argoff < 0)
1825 	return FAIL;
1826 
1827     if (method_call && argoff > 1)
1828     {
1829 	if ((isn = generate_instr(cctx, ISN_SHUFFLE)) == NULL)
1830 	    return FAIL;
1831 	isn->isn_arg.shuffle.shfl_item = argcount;
1832 	isn->isn_arg.shuffle.shfl_up = argoff - 1;
1833     }
1834 
1835     if (argcount > 0)
1836     {
1837 	// Check the types of the arguments.
1838 	argtypes = ((type_T **)stack->ga_data) + stack->ga_len - argcount;
1839 	if (method_call && argoff > 1)
1840 	{
1841 	    int i;
1842 
1843 	    for (i = 0; i < argcount; ++i)
1844 		shuffled_argtypes[i] = (i < argoff - 1)
1845 			    ? argtypes[i + 1]
1846 			    : (i == argoff - 1) ? argtypes[0] : argtypes[i];
1847 	    argtypes = shuffled_argtypes;
1848 	}
1849 	if (internal_func_check_arg_types(argtypes, func_idx, argcount,
1850 								 cctx) == FAIL)
1851 	    return FAIL;
1852 	if (internal_func_is_map(func_idx))
1853 	    maptype = *argtypes;
1854     }
1855 
1856     if ((isn = generate_instr(cctx, ISN_BCALL)) == NULL)
1857 	return FAIL;
1858     isn->isn_arg.bfunc.cbf_idx = func_idx;
1859     isn->isn_arg.bfunc.cbf_argcount = argcount;
1860 
1861     // Drop the argument types and push the return type.
1862     stack->ga_len -= argcount;
1863     if (GA_GROW_FAILS(stack, 1))
1864 	return FAIL;
1865     ((type_T **)stack->ga_data)[stack->ga_len] =
1866 			  internal_func_ret_type(func_idx, argcount, argtypes);
1867     ++stack->ga_len;
1868 
1869     if (maptype != NULL && maptype->tt_member != NULL
1870 					       && maptype->tt_member != &t_any)
1871 	// Check that map() didn't change the item types.
1872 	generate_TYPECHECK(cctx, maptype, -1, 1);
1873 
1874     return OK;
1875 }
1876 
1877 /*
1878  * Generate an ISN_LISTAPPEND instruction.  Works like add().
1879  * Argument count is already checked.
1880  */
1881     static int
1882 generate_LISTAPPEND(cctx_T *cctx)
1883 {
1884     garray_T	*stack = &cctx->ctx_type_stack;
1885     type_T	*list_type;
1886     type_T	*item_type;
1887     type_T	*expected;
1888 
1889     // Caller already checked that list_type is a list.
1890     list_type = ((type_T **)stack->ga_data)[stack->ga_len - 2];
1891     item_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1892     expected = list_type->tt_member;
1893     if (need_type(item_type, expected, -1, 0, cctx, FALSE, FALSE) == FAIL)
1894 	return FAIL;
1895 
1896     if (generate_instr(cctx, ISN_LISTAPPEND) == NULL)
1897 	return FAIL;
1898 
1899     --stack->ga_len;	    // drop the argument
1900     return OK;
1901 }
1902 
1903 /*
1904  * Generate an ISN_BLOBAPPEND instruction.  Works like add().
1905  * Argument count is already checked.
1906  */
1907     static int
1908 generate_BLOBAPPEND(cctx_T *cctx)
1909 {
1910     garray_T	*stack = &cctx->ctx_type_stack;
1911     type_T	*item_type;
1912 
1913     // Caller already checked that blob_type is a blob.
1914     item_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1915     if (need_type(item_type, &t_number, -1, 0, cctx, FALSE, FALSE) == FAIL)
1916 	return FAIL;
1917 
1918     if (generate_instr(cctx, ISN_BLOBAPPEND) == NULL)
1919 	return FAIL;
1920 
1921     --stack->ga_len;	    // drop the argument
1922     return OK;
1923 }
1924 
1925 /*
1926  * Return TRUE if "ufunc" should be compiled, taking into account whether
1927  * "profile" indicates profiling is to be done.
1928  */
1929     int
1930 func_needs_compiling(ufunc_T *ufunc, compiletype_T compile_type)
1931 {
1932     switch (ufunc->uf_def_status)
1933     {
1934 	case UF_TO_BE_COMPILED:
1935 	    return TRUE;
1936 
1937 	case UF_COMPILED:
1938 	{
1939 	    dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
1940 							 + ufunc->uf_dfunc_idx;
1941 
1942 	    switch (compile_type)
1943 	    {
1944 		case CT_PROFILE:
1945 #ifdef FEAT_PROFILE
1946 		    return dfunc->df_instr_prof == NULL;
1947 #endif
1948 		case CT_NONE:
1949 		    return dfunc->df_instr == NULL;
1950 		case CT_DEBUG:
1951 		    return dfunc->df_instr_debug == NULL;
1952 	    }
1953 	}
1954 
1955 	case UF_NOT_COMPILED:
1956 	case UF_COMPILE_ERROR:
1957 	case UF_COMPILING:
1958 	    break;
1959     }
1960     return FALSE;
1961 }
1962 
1963 /*
1964  * Generate an ISN_DCALL or ISN_UCALL instruction.
1965  * Return FAIL if the number of arguments is wrong.
1966  */
1967     static int
1968 generate_CALL(cctx_T *cctx, ufunc_T *ufunc, int pushed_argcount)
1969 {
1970     isn_T	*isn;
1971     garray_T	*stack = &cctx->ctx_type_stack;
1972     int		regular_args = ufunc->uf_args.ga_len;
1973     int		argcount = pushed_argcount;
1974 
1975     RETURN_OK_IF_SKIP(cctx);
1976     if (argcount > regular_args && !has_varargs(ufunc))
1977     {
1978 	semsg(_(e_toomanyarg), printable_func_name(ufunc));
1979 	return FAIL;
1980     }
1981     if (argcount < regular_args - ufunc->uf_def_args.ga_len)
1982     {
1983 	semsg(_(e_toofewarg), printable_func_name(ufunc));
1984 	return FAIL;
1985     }
1986 
1987     if (ufunc->uf_def_status != UF_NOT_COMPILED
1988 	    && ufunc->uf_def_status != UF_COMPILE_ERROR)
1989     {
1990 	int		i;
1991 
1992 	for (i = 0; i < argcount; ++i)
1993 	{
1994 	    type_T *expected;
1995 	    type_T *actual;
1996 
1997 	    actual = ((type_T **)stack->ga_data)[stack->ga_len - argcount + i];
1998 	    if (actual == &t_special
1999 			      && i >= regular_args - ufunc->uf_def_args.ga_len)
2000 	    {
2001 		// assume v:none used for default argument value
2002 		continue;
2003 	    }
2004 	    if (i < regular_args)
2005 	    {
2006 		if (ufunc->uf_arg_types == NULL)
2007 		    continue;
2008 		expected = ufunc->uf_arg_types[i];
2009 	    }
2010 	    else if (ufunc->uf_va_type == NULL
2011 					   || ufunc->uf_va_type == &t_list_any)
2012 		// possibly a lambda or "...: any"
2013 		expected = &t_any;
2014 	    else
2015 		expected = ufunc->uf_va_type->tt_member;
2016 	    if (need_type(actual, expected, -argcount + i, i + 1, cctx,
2017 							  TRUE, FALSE) == FAIL)
2018 	    {
2019 		arg_type_mismatch(expected, actual, i + 1);
2020 		return FAIL;
2021 	    }
2022 	}
2023 	if (func_needs_compiling(ufunc, COMPILE_TYPE(ufunc))
2024 		&& compile_def_function(ufunc, ufunc->uf_ret_type == NULL,
2025 					    COMPILE_TYPE(ufunc), NULL) == FAIL)
2026 	    return FAIL;
2027     }
2028     if (ufunc->uf_def_status == UF_COMPILE_ERROR)
2029     {
2030 	emsg_funcname(_(e_call_to_function_that_failed_to_compile_str),
2031 							       ufunc->uf_name);
2032 	return FAIL;
2033     }
2034 
2035     if ((isn = generate_instr(cctx,
2036 		    ufunc->uf_def_status != UF_NOT_COMPILED ? ISN_DCALL
2037 							 : ISN_UCALL)) == NULL)
2038 	return FAIL;
2039     if (isn->isn_type == ISN_DCALL)
2040     {
2041 	isn->isn_arg.dfunc.cdf_idx = ufunc->uf_dfunc_idx;
2042 	isn->isn_arg.dfunc.cdf_argcount = argcount;
2043     }
2044     else
2045     {
2046 	// A user function may be deleted and redefined later, can't use the
2047 	// ufunc pointer, need to look it up again at runtime.
2048 	isn->isn_arg.ufunc.cuf_name = vim_strsave(ufunc->uf_name);
2049 	isn->isn_arg.ufunc.cuf_argcount = argcount;
2050     }
2051 
2052     stack->ga_len -= argcount; // drop the arguments
2053     if (GA_GROW_FAILS(stack, 1))
2054 	return FAIL;
2055     // add return value
2056     ((type_T **)stack->ga_data)[stack->ga_len] = ufunc->uf_ret_type;
2057     ++stack->ga_len;
2058 
2059     return OK;
2060 }
2061 
2062 /*
2063  * Generate an ISN_UCALL instruction when the function isn't defined yet.
2064  */
2065     static int
2066 generate_UCALL(cctx_T *cctx, char_u *name, int argcount)
2067 {
2068     isn_T	*isn;
2069     garray_T	*stack = &cctx->ctx_type_stack;
2070 
2071     RETURN_OK_IF_SKIP(cctx);
2072     if ((isn = generate_instr(cctx, ISN_UCALL)) == NULL)
2073 	return FAIL;
2074     isn->isn_arg.ufunc.cuf_name = vim_strsave(name);
2075     isn->isn_arg.ufunc.cuf_argcount = argcount;
2076 
2077     stack->ga_len -= argcount; // drop the arguments
2078     if (GA_GROW_FAILS(stack, 1))
2079 	return FAIL;
2080     // add return value
2081     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
2082     ++stack->ga_len;
2083 
2084     return OK;
2085 }
2086 
2087 /*
2088  * Generate an ISN_PCALL instruction.
2089  * "type" is the type of the FuncRef.
2090  */
2091     static int
2092 generate_PCALL(
2093 	cctx_T	*cctx,
2094 	int	argcount,
2095 	char_u	*name,
2096 	type_T	*type,
2097 	int	at_top)
2098 {
2099     isn_T	*isn;
2100     garray_T	*stack = &cctx->ctx_type_stack;
2101     type_T	*ret_type;
2102 
2103     RETURN_OK_IF_SKIP(cctx);
2104 
2105     if (type->tt_type == VAR_ANY)
2106 	ret_type = &t_any;
2107     else if (type->tt_type == VAR_FUNC || type->tt_type == VAR_PARTIAL)
2108     {
2109 	if (type->tt_argcount != -1)
2110 	{
2111 	    int	    varargs = (type->tt_flags & TTFLAG_VARARGS) ? 1 : 0;
2112 
2113 	    if (argcount < type->tt_min_argcount - varargs)
2114 	    {
2115 		semsg(_(e_toofewarg), name);
2116 		return FAIL;
2117 	    }
2118 	    if (!varargs && argcount > type->tt_argcount)
2119 	    {
2120 		semsg(_(e_toomanyarg), name);
2121 		return FAIL;
2122 	    }
2123 	    if (type->tt_args != NULL)
2124 	    {
2125 		int i;
2126 
2127 		for (i = 0; i < argcount; ++i)
2128 		{
2129 		    int	    offset = -argcount + i - (at_top ? 0 : 1);
2130 		    type_T *actual = ((type_T **)stack->ga_data)[
2131 						       stack->ga_len + offset];
2132 		    type_T *expected;
2133 
2134 		    if (varargs && i >= type->tt_argcount - 1)
2135 			expected = type->tt_args[
2136 					     type->tt_argcount - 1]->tt_member;
2137 		    else if (i >= type->tt_min_argcount
2138 						       && actual == &t_special)
2139 			expected = &t_any;
2140 		    else
2141 			expected = type->tt_args[i];
2142 		    if (need_type(actual, expected, offset, i + 1,
2143 						    cctx, TRUE, FALSE) == FAIL)
2144 		    {
2145 			arg_type_mismatch(expected, actual, i + 1);
2146 			return FAIL;
2147 		    }
2148 		}
2149 	    }
2150 	}
2151 	ret_type = type->tt_member;
2152 	if (ret_type == &t_unknown)
2153 	    // return type not known yet, use a runtime check
2154 	    ret_type = &t_any;
2155     }
2156     else
2157     {
2158 	semsg(_(e_not_callable_type_str), name);
2159 	return FAIL;
2160     }
2161 
2162     if ((isn = generate_instr(cctx, ISN_PCALL)) == NULL)
2163 	return FAIL;
2164     isn->isn_arg.pfunc.cpf_top = at_top;
2165     isn->isn_arg.pfunc.cpf_argcount = argcount;
2166 
2167     stack->ga_len -= argcount; // drop the arguments
2168 
2169     // drop the funcref/partial, get back the return value
2170     ((type_T **)stack->ga_data)[stack->ga_len - 1] = ret_type;
2171 
2172     // If partial is above the arguments it must be cleared and replaced with
2173     // the return value.
2174     if (at_top && generate_instr(cctx, ISN_PCALL_END) == NULL)
2175 	return FAIL;
2176 
2177     return OK;
2178 }
2179 
2180 /*
2181  * Generate an ISN_STRINGMEMBER instruction.
2182  */
2183     static int
2184 generate_STRINGMEMBER(cctx_T *cctx, char_u *name, size_t len)
2185 {
2186     isn_T	*isn;
2187     garray_T	*stack = &cctx->ctx_type_stack;
2188     type_T	*type;
2189 
2190     RETURN_OK_IF_SKIP(cctx);
2191     if ((isn = generate_instr(cctx, ISN_STRINGMEMBER)) == NULL)
2192 	return FAIL;
2193     isn->isn_arg.string = vim_strnsave(name, len);
2194 
2195     // check for dict type
2196     type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
2197     if (type->tt_type != VAR_DICT && type != &t_any)
2198     {
2199 	char *tofree;
2200 
2201 	semsg(_(e_expected_dictionary_for_using_key_str_but_got_str),
2202 					       name, type_name(type, &tofree));
2203 	vim_free(tofree);
2204 	return FAIL;
2205     }
2206     // change dict type to dict member type
2207     if (type->tt_type == VAR_DICT)
2208     {
2209 	((type_T **)stack->ga_data)[stack->ga_len - 1] =
2210 		      type->tt_member == &t_unknown ? &t_any : type->tt_member;
2211     }
2212 
2213     return OK;
2214 }
2215 
2216 /*
2217  * Generate an ISN_ECHO instruction.
2218  */
2219     static int
2220 generate_ECHO(cctx_T *cctx, int with_white, int count)
2221 {
2222     isn_T	*isn;
2223 
2224     RETURN_OK_IF_SKIP(cctx);
2225     if ((isn = generate_instr_drop(cctx, ISN_ECHO, count)) == NULL)
2226 	return FAIL;
2227     isn->isn_arg.echo.echo_with_white = with_white;
2228     isn->isn_arg.echo.echo_count = count;
2229 
2230     return OK;
2231 }
2232 
2233 /*
2234  * Generate an ISN_EXECUTE/ISN_ECHOMSG/ISN_ECHOERR instruction.
2235  */
2236     static int
2237 generate_MULT_EXPR(cctx_T *cctx, isntype_T isn_type, int count)
2238 {
2239     isn_T	*isn;
2240 
2241     if ((isn = generate_instr_drop(cctx, isn_type, count)) == NULL)
2242 	return FAIL;
2243     isn->isn_arg.number = count;
2244 
2245     return OK;
2246 }
2247 
2248 /*
2249  * Generate an ISN_PUT instruction.
2250  */
2251     static int
2252 generate_PUT(cctx_T *cctx, int regname, linenr_T lnum)
2253 {
2254     isn_T	*isn;
2255 
2256     RETURN_OK_IF_SKIP(cctx);
2257     if ((isn = generate_instr(cctx, ISN_PUT)) == NULL)
2258 	return FAIL;
2259     isn->isn_arg.put.put_regname = regname;
2260     isn->isn_arg.put.put_lnum = lnum;
2261     return OK;
2262 }
2263 
2264     static int
2265 generate_EXEC(cctx_T *cctx, char_u *line)
2266 {
2267     isn_T	*isn;
2268 
2269     RETURN_OK_IF_SKIP(cctx);
2270     if ((isn = generate_instr(cctx, ISN_EXEC)) == NULL)
2271 	return FAIL;
2272     isn->isn_arg.string = vim_strsave(line);
2273     return OK;
2274 }
2275 
2276     static int
2277 generate_LEGACY_EVAL(cctx_T *cctx, char_u *line)
2278 {
2279     isn_T	*isn;
2280     garray_T	*stack = &cctx->ctx_type_stack;
2281 
2282     RETURN_OK_IF_SKIP(cctx);
2283     if ((isn = generate_instr(cctx, ISN_LEGACY_EVAL)) == NULL)
2284 	return FAIL;
2285     isn->isn_arg.string = vim_strsave(line);
2286 
2287     if (GA_GROW_FAILS(stack, 1))
2288 	return FAIL;
2289     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
2290     ++stack->ga_len;
2291 
2292     return OK;
2293 }
2294 
2295     static int
2296 generate_EXECCONCAT(cctx_T *cctx, int count)
2297 {
2298     isn_T	*isn;
2299 
2300     if ((isn = generate_instr_drop(cctx, ISN_EXECCONCAT, count)) == NULL)
2301 	return FAIL;
2302     isn->isn_arg.number = count;
2303     return OK;
2304 }
2305 
2306 /*
2307  * Generate ISN_RANGE.  Consumes "range".  Return OK/FAIL.
2308  */
2309     static int
2310 generate_RANGE(cctx_T *cctx, char_u *range)
2311 {
2312     isn_T	*isn;
2313     garray_T	*stack = &cctx->ctx_type_stack;
2314 
2315     if ((isn = generate_instr(cctx, ISN_RANGE)) == NULL)
2316 	return FAIL;
2317     isn->isn_arg.string = range;
2318 
2319     if (GA_GROW_FAILS(stack, 1))
2320 	return FAIL;
2321     ((type_T **)stack->ga_data)[stack->ga_len] = &t_number;
2322     ++stack->ga_len;
2323     return OK;
2324 }
2325 
2326     static int
2327 generate_UNPACK(cctx_T *cctx, int var_count, int semicolon)
2328 {
2329     isn_T	*isn;
2330 
2331     RETURN_OK_IF_SKIP(cctx);
2332     if ((isn = generate_instr(cctx, ISN_UNPACK)) == NULL)
2333 	return FAIL;
2334     isn->isn_arg.unpack.unp_count = var_count;
2335     isn->isn_arg.unpack.unp_semicolon = semicolon;
2336     return OK;
2337 }
2338 
2339 /*
2340  * Generate an instruction for any command modifiers.
2341  */
2342     static int
2343 generate_cmdmods(cctx_T *cctx, cmdmod_T *cmod)
2344 {
2345     isn_T	*isn;
2346 
2347     if (has_cmdmod(cmod, FALSE))
2348     {
2349 	cctx->ctx_has_cmdmod = TRUE;
2350 
2351 	if ((isn = generate_instr(cctx, ISN_CMDMOD)) == NULL)
2352 	    return FAIL;
2353 	isn->isn_arg.cmdmod.cf_cmdmod = ALLOC_ONE(cmdmod_T);
2354 	if (isn->isn_arg.cmdmod.cf_cmdmod == NULL)
2355 	    return FAIL;
2356 	mch_memmove(isn->isn_arg.cmdmod.cf_cmdmod, cmod, sizeof(cmdmod_T));
2357 	// filter program now belongs to the instruction
2358 	cmod->cmod_filter_regmatch.regprog = NULL;
2359     }
2360 
2361     return OK;
2362 }
2363 
2364     static int
2365 generate_undo_cmdmods(cctx_T *cctx)
2366 {
2367     if (cctx->ctx_has_cmdmod && generate_instr(cctx, ISN_CMDMOD_REV) == NULL)
2368 	return FAIL;
2369     cctx->ctx_has_cmdmod = FALSE;
2370     return OK;
2371 }
2372 
2373     static int
2374 misplaced_cmdmod(cctx_T *cctx)
2375 {
2376     garray_T	*instr = &cctx->ctx_instr;
2377 
2378     if (cctx->ctx_has_cmdmod
2379 	    && ((isn_T *)instr->ga_data)[instr->ga_len - 1].isn_type
2380 								 == ISN_CMDMOD)
2381     {
2382 	emsg(_(e_misplaced_command_modifier));
2383 	return TRUE;
2384     }
2385     return FALSE;
2386 }
2387 
2388 /*
2389  * Get the index of the current instruction.
2390  * This compenstates for a preceding ISN_CMDMOD and ISN_PROF_START.
2391  */
2392     static int
2393 current_instr_idx(cctx_T *cctx)
2394 {
2395     garray_T	*instr = &cctx->ctx_instr;
2396     int		idx = instr->ga_len;
2397 
2398     while (idx > 0)
2399     {
2400 	if (cctx->ctx_has_cmdmod && ((isn_T *)instr->ga_data)[idx - 1]
2401 						       .isn_type == ISN_CMDMOD)
2402 	{
2403 	    --idx;
2404 	    continue;
2405 	}
2406 #ifdef FEAT_PROFILE
2407 	if (((isn_T *)instr->ga_data)[idx - 1].isn_type == ISN_PROF_START)
2408 	{
2409 	    --idx;
2410 	    continue;
2411 	}
2412 #endif
2413 	if (((isn_T *)instr->ga_data)[idx - 1].isn_type == ISN_DEBUG)
2414 	{
2415 	    --idx;
2416 	    continue;
2417 	}
2418 	break;
2419     }
2420     return idx;
2421 }
2422 
2423 #ifdef FEAT_PROFILE
2424     static void
2425 may_generate_prof_end(cctx_T *cctx, int prof_lnum)
2426 {
2427     if (cctx->ctx_compile_type == CT_PROFILE && prof_lnum >= 0)
2428 	generate_instr(cctx, ISN_PROF_END);
2429 }
2430 #endif
2431 
2432 /*
2433  * Reserve space for a local variable.
2434  * Return the variable or NULL if it failed.
2435  */
2436     static lvar_T *
2437 reserve_local(
2438 	cctx_T	*cctx,
2439 	char_u	*name,
2440 	size_t	len,
2441 	int	isConst,
2442 	type_T	*type)
2443 {
2444     lvar_T  *lvar;
2445     dfunc_T *dfunc;
2446 
2447     if (arg_exists(name, len, NULL, NULL, NULL, cctx) == OK)
2448     {
2449 	emsg_namelen(_(e_str_is_used_as_argument), name, (int)len);
2450 	return NULL;
2451     }
2452 
2453     if (GA_GROW_FAILS(&cctx->ctx_locals, 1))
2454 	return NULL;
2455     lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + cctx->ctx_locals.ga_len++;
2456     CLEAR_POINTER(lvar);
2457 
2458     // Every local variable uses the next entry on the stack.  We could re-use
2459     // the last ones when leaving a scope, but then variables used in a closure
2460     // might get overwritten.  To keep things simple do not re-use stack
2461     // entries.  This is less efficient, but memory is cheap these days.
2462     dfunc = ((dfunc_T *)def_functions.ga_data) + cctx->ctx_ufunc->uf_dfunc_idx;
2463     lvar->lv_idx = dfunc->df_var_names.ga_len;
2464 
2465     lvar->lv_name = vim_strnsave(name, len == 0 ? STRLEN(name) : len);
2466     lvar->lv_const = isConst;
2467     lvar->lv_type = type;
2468 
2469     // Remember the name for debugging.
2470     if (GA_GROW_FAILS(&dfunc->df_var_names, 1))
2471 	return NULL;
2472     ((char_u **)dfunc->df_var_names.ga_data)[lvar->lv_idx] =
2473 						    vim_strsave(lvar->lv_name);
2474     ++dfunc->df_var_names.ga_len;
2475 
2476     return lvar;
2477 }
2478 
2479 /*
2480  * Remove local variables above "new_top".
2481  */
2482     static void
2483 unwind_locals(cctx_T *cctx, int new_top)
2484 {
2485     if (cctx->ctx_locals.ga_len > new_top)
2486     {
2487 	int	idx;
2488 	lvar_T	*lvar;
2489 
2490 	for (idx = new_top; idx < cctx->ctx_locals.ga_len; ++idx)
2491 	{
2492 	    lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + idx;
2493 	    vim_free(lvar->lv_name);
2494 	}
2495     }
2496     cctx->ctx_locals.ga_len = new_top;
2497 }
2498 
2499 /*
2500  * Free all local variables.
2501  */
2502     static void
2503 free_locals(cctx_T *cctx)
2504 {
2505     unwind_locals(cctx, 0);
2506     ga_clear(&cctx->ctx_locals);
2507 }
2508 
2509 /*
2510  * If "check_writable" is ASSIGN_CONST give an error if the variable was
2511  * defined with :final or :const, if "check_writable" is ASSIGN_FINAL give an
2512  * error if the variable was defined with :const.
2513  */
2514     static int
2515 check_item_writable(svar_T *sv, int check_writable, char_u *name)
2516 {
2517     if ((check_writable == ASSIGN_CONST && sv->sv_const != 0)
2518 	    || (check_writable == ASSIGN_FINAL
2519 					      && sv->sv_const == ASSIGN_CONST))
2520     {
2521 	semsg(_(e_cannot_change_readonly_variable_str), name);
2522 	return FAIL;
2523     }
2524     return OK;
2525 }
2526 
2527 /*
2528  * Find "name" in script-local items of script "sid".
2529  * Pass "check_writable" to check_item_writable().
2530  * Returns the index in "sn_var_vals" if found.
2531  * If found but not in "sn_var_vals" returns -1.
2532  * If not found or the variable is not writable returns -2.
2533  */
2534     int
2535 get_script_item_idx(int sid, char_u *name, int check_writable, cctx_T *cctx)
2536 {
2537     hashtab_T	    *ht;
2538     dictitem_T	    *di;
2539     scriptitem_T    *si = SCRIPT_ITEM(sid);
2540     svar_T	    *sv;
2541     int		    idx;
2542 
2543     if (!SCRIPT_ID_VALID(sid))
2544 	return -1;
2545     if (sid == current_sctx.sc_sid)
2546     {
2547 	sallvar_T *sav = find_script_var(name, 0, cctx);
2548 
2549 	if (sav == NULL)
2550 	    return -2;
2551 	idx = sav->sav_var_vals_idx;
2552 	sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
2553 	if (check_item_writable(sv, check_writable, name) == FAIL)
2554 	    return -2;
2555 	return idx;
2556     }
2557 
2558     // First look the name up in the hashtable.
2559     ht = &SCRIPT_VARS(sid);
2560     di = find_var_in_ht(ht, 0, name, TRUE);
2561     if (di == NULL)
2562 	return -2;
2563 
2564     // Now find the svar_T index in sn_var_vals.
2565     for (idx = 0; idx < si->sn_var_vals.ga_len; ++idx)
2566     {
2567 	sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
2568 	if (sv->sv_tv == &di->di_tv)
2569 	{
2570 	    if (check_item_writable(sv, check_writable, name) == FAIL)
2571 		return -2;
2572 	    return idx;
2573 	}
2574     }
2575     return -1;
2576 }
2577 
2578 /*
2579  * Find "name" in imported items of the current script or in "cctx" if not
2580  * NULL.
2581  */
2582     imported_T *
2583 find_imported(char_u *name, size_t len, cctx_T *cctx)
2584 {
2585     int		    idx;
2586 
2587     if (!SCRIPT_ID_VALID(current_sctx.sc_sid))
2588 	return NULL;
2589     if (cctx != NULL)
2590 	for (idx = 0; idx < cctx->ctx_imports.ga_len; ++idx)
2591 	{
2592 	    imported_T *import = ((imported_T *)cctx->ctx_imports.ga_data)
2593 									 + idx;
2594 
2595 	    if (len == 0 ? STRCMP(name, import->imp_name) == 0
2596 			 : STRLEN(import->imp_name) == len
2597 				  && STRNCMP(name, import->imp_name, len) == 0)
2598 		return import;
2599 	}
2600 
2601     return find_imported_in_script(name, len, current_sctx.sc_sid);
2602 }
2603 
2604     imported_T *
2605 find_imported_in_script(char_u *name, size_t len, int sid)
2606 {
2607     scriptitem_T    *si;
2608     int		    idx;
2609 
2610     if (!SCRIPT_ID_VALID(sid))
2611 	return NULL;
2612     si = SCRIPT_ITEM(sid);
2613     for (idx = 0; idx < si->sn_imports.ga_len; ++idx)
2614     {
2615 	imported_T *import = ((imported_T *)si->sn_imports.ga_data) + idx;
2616 
2617 	if (len == 0 ? STRCMP(name, import->imp_name) == 0
2618 		     : STRLEN(import->imp_name) == len
2619 				  && STRNCMP(name, import->imp_name, len) == 0)
2620 	    return import;
2621     }
2622     return NULL;
2623 }
2624 
2625 /*
2626  * Free all imported variables.
2627  */
2628     static void
2629 free_imported(cctx_T *cctx)
2630 {
2631     int idx;
2632 
2633     for (idx = 0; idx < cctx->ctx_imports.ga_len; ++idx)
2634     {
2635 	imported_T *import = ((imported_T *)cctx->ctx_imports.ga_data) + idx;
2636 
2637 	vim_free(import->imp_name);
2638     }
2639     ga_clear(&cctx->ctx_imports);
2640 }
2641 
2642 /*
2643  * Return a pointer to the next line that isn't empty or only contains a
2644  * comment. Skips over white space.
2645  * Returns NULL if there is none.
2646  */
2647     char_u *
2648 peek_next_line_from_context(cctx_T *cctx)
2649 {
2650     int lnum = cctx->ctx_lnum;
2651 
2652     while (++lnum < cctx->ctx_ufunc->uf_lines.ga_len)
2653     {
2654 	char_u *line = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[lnum];
2655 	char_u *p;
2656 
2657 	// ignore NULLs inserted for continuation lines
2658 	if (line != NULL)
2659 	{
2660 	    p = skipwhite(line);
2661 	    if (vim9_bad_comment(p))
2662 		return NULL;
2663 	    if (*p != NUL && !vim9_comment_start(p))
2664 		return p;
2665 	}
2666     }
2667     return NULL;
2668 }
2669 
2670 /*
2671  * Called when checking for a following operator at "arg".  When the rest of
2672  * the line is empty or only a comment, peek the next line.  If there is a next
2673  * line return a pointer to it and set "nextp".
2674  * Otherwise skip over white space.
2675  */
2676     static char_u *
2677 may_peek_next_line(cctx_T *cctx, char_u *arg, char_u **nextp)
2678 {
2679     char_u *p = skipwhite(arg);
2680 
2681     *nextp = NULL;
2682     if (*p == NUL || (VIM_ISWHITE(*arg) && vim9_comment_start(p)))
2683     {
2684 	*nextp = peek_next_line_from_context(cctx);
2685 	if (*nextp != NULL)
2686 	    return *nextp;
2687     }
2688     return p;
2689 }
2690 
2691 /*
2692  * Get the next line of the function from "cctx".
2693  * Skips over empty lines.  Skips over comment lines if "skip_comment" is TRUE.
2694  * Returns NULL when at the end.
2695  */
2696     char_u *
2697 next_line_from_context(cctx_T *cctx, int skip_comment)
2698 {
2699     char_u	*line;
2700 
2701     do
2702     {
2703 	++cctx->ctx_lnum;
2704 	if (cctx->ctx_lnum >= cctx->ctx_ufunc->uf_lines.ga_len)
2705 	{
2706 	    line = NULL;
2707 	    break;
2708 	}
2709 	line = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum];
2710 	cctx->ctx_line_start = line;
2711 	SOURCING_LNUM = cctx->ctx_lnum + 1;
2712     } while (line == NULL || *skipwhite(line) == NUL
2713 		     || (skip_comment && vim9_comment_start(skipwhite(line))));
2714     return line;
2715 }
2716 
2717 /*
2718  * Skip over white space at "whitep" and assign to "*arg".
2719  * If "*arg" is at the end of the line, advance to the next line.
2720  * Also when "whitep" points to white space and "*arg" is on a "#".
2721  * Return FAIL if beyond the last line, "*arg" is unmodified then.
2722  */
2723     static int
2724 may_get_next_line(char_u *whitep, char_u **arg, cctx_T *cctx)
2725 {
2726     *arg = skipwhite(whitep);
2727     if (vim9_bad_comment(*arg))
2728 	return FAIL;
2729     if (**arg == NUL || (VIM_ISWHITE(*whitep) && vim9_comment_start(*arg)))
2730     {
2731 	char_u *next = next_line_from_context(cctx, TRUE);
2732 
2733 	if (next == NULL)
2734 	    return FAIL;
2735 	*arg = skipwhite(next);
2736     }
2737     return OK;
2738 }
2739 
2740 /*
2741  * Idem, and give an error when failed.
2742  */
2743     static int
2744 may_get_next_line_error(char_u *whitep, char_u **arg, cctx_T *cctx)
2745 {
2746     if (may_get_next_line(whitep, arg, cctx) == FAIL)
2747     {
2748 	SOURCING_LNUM = cctx->ctx_lnum + 1;
2749 	emsg(_(e_line_incomplete));
2750 	return FAIL;
2751     }
2752     return OK;
2753 }
2754 
2755 
2756 // Structure passed between the compile_expr* functions to keep track of
2757 // constants that have been parsed but for which no code was produced yet.  If
2758 // possible expressions on these constants are applied at compile time.  If
2759 // that is not possible, the code to push the constants needs to be generated
2760 // before other instructions.
2761 // Using 50 should be more than enough of 5 levels of ().
2762 #define PPSIZE 50
2763 typedef struct {
2764     typval_T	pp_tv[PPSIZE];	// stack of ppconst constants
2765     int		pp_used;	// active entries in pp_tv[]
2766     int		pp_is_const;	// all generated code was constants, used for a
2767 				// list or dict with constant members
2768 } ppconst_T;
2769 
2770 static int compile_expr0_ext(char_u **arg,  cctx_T *cctx, int *is_const);
2771 static int compile_expr0(char_u **arg,  cctx_T *cctx);
2772 static int compile_expr1(char_u **arg,  cctx_T *cctx, ppconst_T *ppconst);
2773 
2774 /*
2775  * Generate a PUSH instruction for "tv".
2776  * "tv" will be consumed or cleared.
2777  * Nothing happens if "tv" is NULL or of type VAR_UNKNOWN;
2778  */
2779     static int
2780 generate_tv_PUSH(cctx_T *cctx, typval_T *tv)
2781 {
2782     if (tv != NULL)
2783     {
2784 	switch (tv->v_type)
2785 	{
2786 	    case VAR_UNKNOWN:
2787 		break;
2788 	    case VAR_BOOL:
2789 		generate_PUSHBOOL(cctx, tv->vval.v_number);
2790 		break;
2791 	    case VAR_SPECIAL:
2792 		generate_PUSHSPEC(cctx, tv->vval.v_number);
2793 		break;
2794 	    case VAR_NUMBER:
2795 		generate_PUSHNR(cctx, tv->vval.v_number);
2796 		break;
2797 #ifdef FEAT_FLOAT
2798 	    case VAR_FLOAT:
2799 		generate_PUSHF(cctx, tv->vval.v_float);
2800 		break;
2801 #endif
2802 	    case VAR_BLOB:
2803 		generate_PUSHBLOB(cctx, tv->vval.v_blob);
2804 		tv->vval.v_blob = NULL;
2805 		break;
2806 	    case VAR_STRING:
2807 		generate_PUSHS(cctx, &tv->vval.v_string);
2808 		tv->vval.v_string = NULL;
2809 		break;
2810 	    default:
2811 		iemsg("constant type not supported");
2812 		clear_tv(tv);
2813 		return FAIL;
2814 	}
2815 	tv->v_type = VAR_UNKNOWN;
2816     }
2817     return OK;
2818 }
2819 
2820 /*
2821  * Generate code for any ppconst entries.
2822  */
2823     static int
2824 generate_ppconst(cctx_T *cctx, ppconst_T *ppconst)
2825 {
2826     int	    i;
2827     int	    ret = OK;
2828     int	    save_skip = cctx->ctx_skip;
2829 
2830     cctx->ctx_skip = SKIP_NOT;
2831     for (i = 0; i < ppconst->pp_used; ++i)
2832 	if (generate_tv_PUSH(cctx, &ppconst->pp_tv[i]) == FAIL)
2833 	    ret = FAIL;
2834     ppconst->pp_used = 0;
2835     cctx->ctx_skip = save_skip;
2836     return ret;
2837 }
2838 
2839 /*
2840  * Check that the last item of "ppconst" is a bool.
2841  */
2842     static int
2843 check_ppconst_bool(ppconst_T *ppconst)
2844 {
2845     if (ppconst->pp_used > 0)
2846     {
2847 	typval_T    *tv = &ppconst->pp_tv[ppconst->pp_used - 1];
2848 	where_T	    where = WHERE_INIT;
2849 
2850 	return check_typval_type(&t_bool, tv, where);
2851     }
2852     return OK;
2853 }
2854 
2855 /*
2856  * Clear ppconst constants.  Used when failing.
2857  */
2858     static void
2859 clear_ppconst(ppconst_T *ppconst)
2860 {
2861     int	    i;
2862 
2863     for (i = 0; i < ppconst->pp_used; ++i)
2864 	clear_tv(&ppconst->pp_tv[i]);
2865     ppconst->pp_used = 0;
2866 }
2867 
2868 /*
2869  * Compile getting a member from a list/dict/string/blob.  Stack has the
2870  * indexable value and the index or the two indexes of a slice.
2871  */
2872     static int
2873 compile_member(int is_slice, cctx_T *cctx)
2874 {
2875     type_T	**typep;
2876     garray_T	*stack = &cctx->ctx_type_stack;
2877     vartype_T	vartype;
2878     type_T	*idxtype;
2879 
2880     // We can index a list, dict and blob.  If we don't know the type
2881     // we can use the index value type.  If we still don't know use an "ANY"
2882     // instruction.
2883     typep = ((type_T **)stack->ga_data) + stack->ga_len
2884 						  - (is_slice ? 3 : 2);
2885     vartype = (*typep)->tt_type;
2886     idxtype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
2887     // If the index is a string, the variable must be a Dict.
2888     if (*typep == &t_any && idxtype == &t_string)
2889 	vartype = VAR_DICT;
2890     if (vartype == VAR_STRING || vartype == VAR_LIST || vartype == VAR_BLOB)
2891     {
2892 	if (need_type(idxtype, &t_number, -1, 0, cctx, FALSE, FALSE) == FAIL)
2893 	    return FAIL;
2894 	if (is_slice)
2895 	{
2896 	    idxtype = ((type_T **)stack->ga_data)[stack->ga_len - 2];
2897 	    if (need_type(idxtype, &t_number, -2, 0, cctx,
2898 							 FALSE, FALSE) == FAIL)
2899 		return FAIL;
2900 	}
2901     }
2902 
2903     if (vartype == VAR_DICT)
2904     {
2905 	if (is_slice)
2906 	{
2907 	    emsg(_(e_cannot_slice_dictionary));
2908 	    return FAIL;
2909 	}
2910 	if ((*typep)->tt_type == VAR_DICT)
2911 	{
2912 	    *typep = (*typep)->tt_member;
2913 	    if (*typep == &t_unknown)
2914 		// empty dict was used
2915 		*typep = &t_any;
2916 	}
2917 	else
2918 	{
2919 	    if (need_type(*typep, &t_dict_any, -2, 0, cctx,
2920 							 FALSE, FALSE) == FAIL)
2921 		return FAIL;
2922 	    *typep = &t_any;
2923 	}
2924 	if (may_generate_2STRING(-1, FALSE, cctx) == FAIL)
2925 	    return FAIL;
2926 	if (generate_instr_drop(cctx, ISN_MEMBER, 1) == FAIL)
2927 	    return FAIL;
2928     }
2929     else if (vartype == VAR_STRING)
2930     {
2931 	*typep = &t_string;
2932 	if ((is_slice
2933 		? generate_instr_drop(cctx, ISN_STRSLICE, 2)
2934 		: generate_instr_drop(cctx, ISN_STRINDEX, 1)) == FAIL)
2935 	    return FAIL;
2936     }
2937     else if (vartype == VAR_BLOB)
2938     {
2939 	if (is_slice)
2940 	{
2941 	    *typep = &t_blob;
2942 	    if (generate_instr_drop(cctx, ISN_BLOBSLICE, 2) == FAIL)
2943 		return FAIL;
2944 	}
2945 	else
2946 	{
2947 	    *typep = &t_number;
2948 	    if (generate_instr_drop(cctx, ISN_BLOBINDEX, 1) == FAIL)
2949 		return FAIL;
2950 	}
2951     }
2952     else if (vartype == VAR_LIST || *typep == &t_any)
2953     {
2954 	if (is_slice)
2955 	{
2956 	    if (generate_instr_drop(cctx,
2957 		     vartype == VAR_LIST ?  ISN_LISTSLICE : ISN_ANYSLICE,
2958 							    2) == FAIL)
2959 		return FAIL;
2960 	}
2961 	else
2962 	{
2963 	    if ((*typep)->tt_type == VAR_LIST)
2964 	    {
2965 		*typep = (*typep)->tt_member;
2966 		if (*typep == &t_unknown)
2967 		    // empty list was used
2968 		    *typep = &t_any;
2969 	    }
2970 	    if (generate_instr_drop(cctx,
2971 			vartype == VAR_LIST ?  ISN_LISTINDEX : ISN_ANYINDEX, 1)
2972 								       == FAIL)
2973 		return FAIL;
2974 	}
2975     }
2976     else
2977     {
2978 	emsg(_(e_string_list_dict_or_blob_required));
2979 	return FAIL;
2980     }
2981     return OK;
2982 }
2983 
2984 /*
2985  * Generate an instruction to load script-local variable "name", without the
2986  * leading "s:".
2987  * Also finds imported variables.
2988  */
2989     static int
2990 compile_load_scriptvar(
2991 	cctx_T *cctx,
2992 	char_u *name,	    // variable NUL terminated
2993 	char_u *start,	    // start of variable
2994 	char_u **end,	    // end of variable
2995 	int    error)	    // when TRUE may give error
2996 {
2997     scriptitem_T    *si;
2998     int		    idx;
2999     imported_T	    *import;
3000 
3001     if (!SCRIPT_ID_VALID(current_sctx.sc_sid))
3002 	return FAIL;
3003     si = SCRIPT_ITEM(current_sctx.sc_sid);
3004     idx = get_script_item_idx(current_sctx.sc_sid, name, 0, cctx);
3005     if (idx == -1 || si->sn_version != SCRIPT_VERSION_VIM9)
3006     {
3007 	// variable is not in sn_var_vals: old style script.
3008 	return generate_OLDSCRIPT(cctx, ISN_LOADS, name, current_sctx.sc_sid,
3009 								       &t_any);
3010     }
3011     if (idx >= 0)
3012     {
3013 	svar_T		*sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
3014 
3015 	generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
3016 					current_sctx.sc_sid, idx, sv->sv_type);
3017 	return OK;
3018     }
3019 
3020     import = find_imported(name, 0, cctx);
3021     if (import != NULL)
3022     {
3023 	if (import->imp_flags & IMP_FLAGS_STAR)
3024 	{
3025 	    char_u	*p = skipwhite(*end);
3026 	    char_u	*exp_name;
3027 	    int		cc;
3028 	    ufunc_T	*ufunc;
3029 	    type_T	*type;
3030 
3031 	    // Used "import * as Name", need to lookup the member.
3032 	    if (*p != '.')
3033 	    {
3034 		semsg(_(e_expected_dot_after_name_str), start);
3035 		return FAIL;
3036 	    }
3037 	    ++p;
3038 	    if (VIM_ISWHITE(*p))
3039 	    {
3040 		emsg(_(e_no_white_space_allowed_after_dot));
3041 		return FAIL;
3042 	    }
3043 
3044 	    // isolate one name
3045 	    exp_name = p;
3046 	    while (eval_isnamec(*p))
3047 		++p;
3048 	    cc = *p;
3049 	    *p = NUL;
3050 
3051 	    idx = find_exported(import->imp_sid, exp_name, &ufunc, &type,
3052 								   cctx, TRUE);
3053 	    *p = cc;
3054 	    p = skipwhite(p);
3055 	    *end = p;
3056 
3057 	    if (idx < 0)
3058 	    {
3059 		if (*p == '(' && ufunc != NULL)
3060 		{
3061 		    generate_PUSHFUNC(cctx, ufunc->uf_name, import->imp_type);
3062 		    return OK;
3063 		}
3064 		return FAIL;
3065 	    }
3066 
3067 	    generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
3068 		    import->imp_sid,
3069 		    idx,
3070 		    type);
3071 	}
3072 	else if (import->imp_funcname != NULL)
3073 	    generate_PUSHFUNC(cctx, import->imp_funcname, import->imp_type);
3074 	else
3075 	    generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
3076 		    import->imp_sid,
3077 		    import->imp_var_vals_idx,
3078 		    import->imp_type);
3079 	return OK;
3080     }
3081 
3082     if (error)
3083 	semsg(_(e_item_not_found_str), name);
3084     return FAIL;
3085 }
3086 
3087     static int
3088 generate_funcref(cctx_T *cctx, char_u *name)
3089 {
3090     ufunc_T *ufunc = find_func(name, FALSE, cctx);
3091 
3092     if (ufunc == NULL)
3093 	return FAIL;
3094 
3095     // Need to compile any default values to get the argument types.
3096     if (func_needs_compiling(ufunc, COMPILE_TYPE(ufunc))
3097 	    && compile_def_function(ufunc, TRUE, COMPILE_TYPE(ufunc), NULL)
3098 								       == FAIL)
3099 	return FAIL;
3100     return generate_PUSHFUNC(cctx, ufunc->uf_name, ufunc->uf_func_type);
3101 }
3102 
3103 /*
3104  * Compile a variable name into a load instruction.
3105  * "end" points to just after the name.
3106  * "is_expr" is TRUE when evaluating an expression, might be a funcref.
3107  * When "error" is FALSE do not give an error when not found.
3108  */
3109     static int
3110 compile_load(
3111 	char_u **arg,
3112 	char_u *end_arg,
3113 	cctx_T	*cctx,
3114 	int	is_expr,
3115 	int	error)
3116 {
3117     type_T	*type;
3118     char_u	*name = NULL;
3119     char_u	*end = end_arg;
3120     int		res = FAIL;
3121     int		prev_called_emsg = called_emsg;
3122 
3123     if (*(*arg + 1) == ':')
3124     {
3125 	if (end <= *arg + 2)
3126 	{
3127 	    isntype_T  isn_type;
3128 
3129 	    // load dictionary of namespace
3130 	    switch (**arg)
3131 	    {
3132 		case 'g': isn_type = ISN_LOADGDICT; break;
3133 		case 'w': isn_type = ISN_LOADWDICT; break;
3134 		case 't': isn_type = ISN_LOADTDICT; break;
3135 		case 'b': isn_type = ISN_LOADBDICT; break;
3136 		default:
3137 		    semsg(_(e_namespace_not_supported_str), *arg);
3138 		    goto theend;
3139 	    }
3140 	    if (generate_instr_type(cctx, isn_type, &t_dict_any) == NULL)
3141 		goto theend;
3142 	    res = OK;
3143 	}
3144 	else
3145 	{
3146 	    isntype_T  isn_type = ISN_DROP;
3147 
3148 	    // load namespaced variable
3149 	    name = vim_strnsave(*arg + 2, end - (*arg + 2));
3150 	    if (name == NULL)
3151 		return FAIL;
3152 
3153 	    switch (**arg)
3154 	    {
3155 		case 'v': res = generate_LOADV(cctx, name, error);
3156 			  break;
3157 		case 's': if (is_expr && ASCII_ISUPPER(*name)
3158 				       && find_func(name, FALSE, cctx) != NULL)
3159 			      res = generate_funcref(cctx, name);
3160 			  else
3161 			      res = compile_load_scriptvar(cctx, name,
3162 							    NULL, &end, error);
3163 			  break;
3164 		case 'g': if (vim_strchr(name, AUTOLOAD_CHAR) == NULL)
3165 			  {
3166 			      if (is_expr && ASCII_ISUPPER(*name)
3167 				       && find_func(name, FALSE, cctx) != NULL)
3168 				  res = generate_funcref(cctx, name);
3169 			      else
3170 				  isn_type = ISN_LOADG;
3171 			  }
3172 			  else
3173 			  {
3174 			      isn_type = ISN_LOADAUTO;
3175 			      vim_free(name);
3176 			      name = vim_strnsave(*arg, end - *arg);
3177 			      if (name == NULL)
3178 				  return FAIL;
3179 			  }
3180 			  break;
3181 		case 'w': isn_type = ISN_LOADW; break;
3182 		case 't': isn_type = ISN_LOADT; break;
3183 		case 'b': isn_type = ISN_LOADB; break;
3184 		default:  // cannot happen, just in case
3185 			  semsg(_(e_namespace_not_supported_str), *arg);
3186 			  goto theend;
3187 	    }
3188 	    if (isn_type != ISN_DROP)
3189 	    {
3190 		// Global, Buffer-local, Window-local and Tabpage-local
3191 		// variables can be defined later, thus we don't check if it
3192 		// exists, give an error at runtime.
3193 		res = generate_LOAD(cctx, isn_type, 0, name, &t_any);
3194 	    }
3195 	}
3196     }
3197     else
3198     {
3199 	size_t	    len = end - *arg;
3200 	int	    idx;
3201 	int	    gen_load = FALSE;
3202 	int	    gen_load_outer = 0;
3203 
3204 	name = vim_strnsave(*arg, end - *arg);
3205 	if (name == NULL)
3206 	    return FAIL;
3207 
3208 	if (vim_strchr(name, AUTOLOAD_CHAR) != NULL)
3209 	{
3210 	    script_autoload(name, FALSE);
3211 	    res = generate_LOAD(cctx, ISN_LOADAUTO, 0, name, &t_any);
3212 	}
3213 	else if (arg_exists(*arg, len, &idx, &type, &gen_load_outer, cctx)
3214 									 == OK)
3215 	{
3216 	    if (gen_load_outer == 0)
3217 		gen_load = TRUE;
3218 	}
3219 	else
3220 	{
3221 	    lvar_T lvar;
3222 
3223 	    if (lookup_local(*arg, len, &lvar, cctx) == OK)
3224 	    {
3225 		type = lvar.lv_type;
3226 		idx = lvar.lv_idx;
3227 		if (lvar.lv_from_outer != 0)
3228 		    gen_load_outer = lvar.lv_from_outer;
3229 		else
3230 		    gen_load = TRUE;
3231 	    }
3232 	    else
3233 	    {
3234 		// "var" can be script-local even without using "s:" if it
3235 		// already exists in a Vim9 script or when it's imported.
3236 		if (script_var_exists(*arg, len, cctx) == OK
3237 			|| find_imported(name, 0, cctx) != NULL)
3238 		   res = compile_load_scriptvar(cctx, name, *arg, &end, FALSE);
3239 
3240 		// When evaluating an expression and the name starts with an
3241 		// uppercase letter it can be a user defined function.
3242 		// generate_funcref() will fail if the function can't be found.
3243 		if (res == FAIL && is_expr && ASCII_ISUPPER(*name))
3244 		    res = generate_funcref(cctx, name);
3245 	    }
3246 	}
3247 	if (gen_load)
3248 	    res = generate_LOAD(cctx, ISN_LOAD, idx, NULL, type);
3249 	if (gen_load_outer > 0)
3250 	{
3251 	    res = generate_LOADOUTER(cctx, idx, gen_load_outer, type);
3252 	    cctx->ctx_outer_used = TRUE;
3253 	}
3254     }
3255 
3256     *arg = end;
3257 
3258 theend:
3259     if (res == FAIL && error && called_emsg == prev_called_emsg)
3260 	semsg(_(e_variable_not_found_str), name);
3261     vim_free(name);
3262     return res;
3263 }
3264 
3265     static void
3266 clear_instr_ga(garray_T *gap)
3267 {
3268     int idx;
3269 
3270     for (idx = 0; idx < gap->ga_len; ++idx)
3271 	delete_instr(((isn_T *)gap->ga_data) + idx);
3272     ga_clear(gap);
3273 }
3274 
3275 /*
3276  * Compile a string in a ISN_PUSHS instruction into an ISN_INSTR.
3277  * Returns FAIL if compilation fails.
3278  */
3279     static int
3280 compile_string(isn_T *isn, cctx_T *cctx)
3281 {
3282     char_u	*s = isn->isn_arg.string;
3283     garray_T	save_ga = cctx->ctx_instr;
3284     int		expr_res;
3285     int		trailing_error;
3286     int		instr_count;
3287     isn_T	*instr = NULL;
3288 
3289     // Remove the string type from the stack.
3290     --cctx->ctx_type_stack.ga_len;
3291 
3292     // Temporarily reset the list of instructions so that the jump labels are
3293     // correct.
3294     cctx->ctx_instr.ga_len = 0;
3295     cctx->ctx_instr.ga_maxlen = 0;
3296     cctx->ctx_instr.ga_data = NULL;
3297     expr_res = compile_expr0(&s, cctx);
3298     s = skipwhite(s);
3299     trailing_error = *s != NUL;
3300 
3301     if (expr_res == FAIL || trailing_error
3302 				       || GA_GROW_FAILS(&cctx->ctx_instr, 1))
3303     {
3304 	if (trailing_error)
3305 	    semsg(_(e_trailing_arg), s);
3306 	clear_instr_ga(&cctx->ctx_instr);
3307 	cctx->ctx_instr = save_ga;
3308 	++cctx->ctx_type_stack.ga_len;
3309 	return FAIL;
3310     }
3311 
3312     // Move the generated instructions into the ISN_INSTR instruction, then
3313     // restore the list of instructions.
3314     instr_count = cctx->ctx_instr.ga_len;
3315     instr = cctx->ctx_instr.ga_data;
3316     instr[instr_count].isn_type = ISN_FINISH;
3317 
3318     cctx->ctx_instr = save_ga;
3319     vim_free(isn->isn_arg.string);
3320     isn->isn_type = ISN_INSTR;
3321     isn->isn_arg.instr = instr;
3322     return OK;
3323 }
3324 
3325 /*
3326  * Compile the argument expressions.
3327  * "arg" points to just after the "(" and is advanced to after the ")"
3328  */
3329     static int
3330 compile_arguments(char_u **arg, cctx_T *cctx, int *argcount, int is_searchpair)
3331 {
3332     char_u  *p = *arg;
3333     char_u  *whitep = *arg;
3334     int	    must_end = FALSE;
3335     int	    instr_count;
3336 
3337     for (;;)
3338     {
3339 	if (may_get_next_line(whitep, &p, cctx) == FAIL)
3340 	    goto failret;
3341 	if (*p == ')')
3342 	{
3343 	    *arg = p + 1;
3344 	    return OK;
3345 	}
3346 	if (must_end)
3347 	{
3348 	    semsg(_(e_missing_comma_before_argument_str), p);
3349 	    return FAIL;
3350 	}
3351 
3352 	instr_count = cctx->ctx_instr.ga_len;
3353 	if (compile_expr0(&p, cctx) == FAIL)
3354 	    return FAIL;
3355 	++*argcount;
3356 
3357 	if (is_searchpair && *argcount == 5
3358 		&& cctx->ctx_instr.ga_len == instr_count + 1)
3359 	{
3360 	    isn_T *isn = ((isn_T *)cctx->ctx_instr.ga_data) + instr_count;
3361 
3362 	    // {skip} argument of searchpair() can be compiled if not empty
3363 	    if (isn->isn_type == ISN_PUSHS && *isn->isn_arg.string != NUL)
3364 		compile_string(isn, cctx);
3365 	}
3366 
3367 	if (*p != ',' && *skipwhite(p) == ',')
3368 	{
3369 	    semsg(_(e_no_white_space_allowed_before_str_str), ",", p);
3370 	    p = skipwhite(p);
3371 	}
3372 	if (*p == ',')
3373 	{
3374 	    ++p;
3375 	    if (*p != NUL && !VIM_ISWHITE(*p))
3376 		semsg(_(e_white_space_required_after_str_str), ",", p - 1);
3377 	}
3378 	else
3379 	    must_end = TRUE;
3380 	whitep = p;
3381 	p = skipwhite(p);
3382     }
3383 failret:
3384     emsg(_(e_missing_close));
3385     return FAIL;
3386 }
3387 
3388 /*
3389  * Compile a function call:  name(arg1, arg2)
3390  * "arg" points to "name", "arg + varlen" to the "(".
3391  * "argcount_init" is 1 for "value->method()"
3392  * Instructions:
3393  *	EVAL arg1
3394  *	EVAL arg2
3395  *	BCALL / DCALL / UCALL
3396  */
3397     static int
3398 compile_call(
3399 	char_u	    **arg,
3400 	size_t	    varlen,
3401 	cctx_T	    *cctx,
3402 	ppconst_T   *ppconst,
3403 	int	    argcount_init)
3404 {
3405     char_u	*name = *arg;
3406     char_u	*p;
3407     int		argcount = argcount_init;
3408     char_u	namebuf[100];
3409     char_u	fname_buf[FLEN_FIXED + 1];
3410     char_u	*tofree = NULL;
3411     int		error = FCERR_NONE;
3412     ufunc_T	*ufunc = NULL;
3413     int		res = FAIL;
3414     int		is_autoload;
3415     int		is_searchpair;
3416 
3417     // We can evaluate "has('name')" at compile time.
3418     // We always evaluate "exists_compiled()" at compile time.
3419     if ((varlen == 3 && STRNCMP(*arg, "has", 3) == 0)
3420 	    || (varlen == 15 && STRNCMP(*arg, "exists_compiled", 6) == 0))
3421     {
3422 	char_u	    *s = skipwhite(*arg + varlen + 1);
3423 	typval_T    argvars[2];
3424 	int	    is_has = **arg == 'h';
3425 
3426 	argvars[0].v_type = VAR_UNKNOWN;
3427 	if (*s == '"')
3428 	    (void)eval_string(&s, &argvars[0], TRUE);
3429 	else if (*s == '\'')
3430 	    (void)eval_lit_string(&s, &argvars[0], TRUE);
3431 	s = skipwhite(s);
3432 	if (*s == ')' && argvars[0].v_type == VAR_STRING
3433 	       && ((is_has && !dynamic_feature(argvars[0].vval.v_string))
3434 		    || !is_has))
3435 	{
3436 	    typval_T	*tv = &ppconst->pp_tv[ppconst->pp_used];
3437 
3438 	    *arg = s + 1;
3439 	    argvars[1].v_type = VAR_UNKNOWN;
3440 	    tv->v_type = VAR_NUMBER;
3441 	    tv->vval.v_number = 0;
3442 	    if (is_has)
3443 		f_has(argvars, tv);
3444 	    else
3445 		f_exists(argvars, tv);
3446 	    clear_tv(&argvars[0]);
3447 	    ++ppconst->pp_used;
3448 	    return OK;
3449 	}
3450 	clear_tv(&argvars[0]);
3451 	if (!is_has)
3452 	{
3453 	    emsg(_(e_argument_of_exists_compiled_must_be_literal_string));
3454 	    return FAIL;
3455 	}
3456     }
3457 
3458     if (generate_ppconst(cctx, ppconst) == FAIL)
3459 	return FAIL;
3460 
3461     if (varlen >= sizeof(namebuf))
3462     {
3463 	semsg(_(e_name_too_long_str), name);
3464 	return FAIL;
3465     }
3466     vim_strncpy(namebuf, *arg, varlen);
3467     name = fname_trans_sid(namebuf, fname_buf, &tofree, &error);
3468 
3469     // We handle the "skip" argument of searchpair() and searchpairpos()
3470     // differently.
3471     is_searchpair = (varlen == 6 && STRNCMP(*arg, "search", 6) == 0)
3472 	         || (varlen == 9 && STRNCMP(*arg, "searchpos", 9) == 0)
3473 	        || (varlen == 10 && STRNCMP(*arg, "searchpair", 10) == 0)
3474 	        || (varlen == 13 && STRNCMP(*arg, "searchpairpos", 13) == 0);
3475 
3476     *arg = skipwhite(*arg + varlen + 1);
3477     if (compile_arguments(arg, cctx, &argcount, is_searchpair) == FAIL)
3478 	goto theend;
3479 
3480     is_autoload = vim_strchr(name, AUTOLOAD_CHAR) != NULL;
3481     if (ASCII_ISLOWER(*name) && name[1] != ':' && !is_autoload)
3482     {
3483 	int	    idx;
3484 
3485 	// builtin function
3486 	idx = find_internal_func(name);
3487 	if (idx >= 0)
3488 	{
3489 	    if (STRCMP(name, "flatten") == 0)
3490 	    {
3491 		emsg(_(e_cannot_use_flatten_in_vim9_script));
3492 		goto theend;
3493 	    }
3494 
3495 	    if (STRCMP(name, "add") == 0 && argcount == 2)
3496 	    {
3497 		garray_T    *stack = &cctx->ctx_type_stack;
3498 		type_T	    *type = ((type_T **)stack->ga_data)[
3499 							    stack->ga_len - 2];
3500 
3501 		// add() can be compiled to instructions if we know the type
3502 		if (type->tt_type == VAR_LIST)
3503 		{
3504 		    // inline "add(list, item)" so that the type can be checked
3505 		    res = generate_LISTAPPEND(cctx);
3506 		    idx = -1;
3507 		}
3508 		else if (type->tt_type == VAR_BLOB)
3509 		{
3510 		    // inline "add(blob, nr)" so that the type can be checked
3511 		    res = generate_BLOBAPPEND(cctx);
3512 		    idx = -1;
3513 		}
3514 	    }
3515 
3516 	    if (idx >= 0)
3517 		res = generate_BCALL(cctx, idx, argcount, argcount_init == 1);
3518 	}
3519 	else
3520 	    semsg(_(e_unknownfunc), namebuf);
3521 	goto theend;
3522     }
3523 
3524     // An argument or local variable can be a function reference, this
3525     // overrules a function name.
3526     if (lookup_local(namebuf, varlen, NULL, cctx) == FAIL
3527 	    && arg_exists(namebuf, varlen, NULL, NULL, NULL, cctx) != OK)
3528     {
3529 	// If we can find the function by name generate the right call.
3530 	// Skip global functions here, a local funcref takes precedence.
3531 	ufunc = find_func(name, FALSE, cctx);
3532 	if (ufunc != NULL && !func_is_global(ufunc))
3533 	{
3534 	    res = generate_CALL(cctx, ufunc, argcount);
3535 	    goto theend;
3536 	}
3537     }
3538 
3539     // If the name is a variable, load it and use PCALL.
3540     // Not for g:Func(), we don't know if it is a variable or not.
3541     // Not for eome#Func(), it will be loaded later.
3542     p = namebuf;
3543     if (STRNCMP(namebuf, "g:", 2) != 0 && !is_autoload
3544 	    && compile_load(&p, namebuf + varlen, cctx, FALSE, FALSE) == OK)
3545     {
3546 	garray_T    *stack = &cctx->ctx_type_stack;
3547 	type_T	    *type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
3548 
3549 	res = generate_PCALL(cctx, argcount, namebuf, type, FALSE);
3550 	goto theend;
3551     }
3552 
3553     // If we can find a global function by name generate the right call.
3554     if (ufunc != NULL)
3555     {
3556 	res = generate_CALL(cctx, ufunc, argcount);
3557 	goto theend;
3558     }
3559 
3560     // A global function may be defined only later.  Need to figure out at
3561     // runtime.  Also handles a FuncRef at runtime.
3562     if (STRNCMP(namebuf, "g:", 2) == 0 || is_autoload)
3563 	res = generate_UCALL(cctx, name, argcount);
3564     else
3565 	semsg(_(e_unknownfunc), namebuf);
3566 
3567 theend:
3568     vim_free(tofree);
3569     return res;
3570 }
3571 
3572 // like NAMESPACE_CHAR but with 'a' and 'l'.
3573 #define VIM9_NAMESPACE_CHAR	(char_u *)"bgstvw"
3574 
3575 /*
3576  * Find the end of a variable or function name.  Unlike find_name_end() this
3577  * does not recognize magic braces.
3578  * When "use_namespace" is TRUE recognize "b:", "s:", etc.
3579  * Return a pointer to just after the name.  Equal to "arg" if there is no
3580  * valid name.
3581  */
3582     static char_u *
3583 to_name_end(char_u *arg, int use_namespace)
3584 {
3585     char_u	*p;
3586 
3587     // Quick check for valid starting character.
3588     if (!eval_isnamec1(*arg))
3589 	return arg;
3590 
3591     for (p = arg + 1; *p != NUL && eval_isnamec(*p); MB_PTR_ADV(p))
3592 	// Include a namespace such as "s:var" and "v:var".  But "n:" is not
3593 	// and can be used in slice "[n:]".
3594 	if (*p == ':' && (p != arg + 1
3595 			     || !use_namespace
3596 			     || vim_strchr(VIM9_NAMESPACE_CHAR, *arg) == NULL))
3597 	    break;
3598     return p;
3599 }
3600 
3601 /*
3602  * Like to_name_end() but also skip over a list or dict constant.
3603  * Also accept "<SNR>123_Func".
3604  * This intentionally does not handle line continuation.
3605  */
3606     char_u *
3607 to_name_const_end(char_u *arg)
3608 {
3609     char_u	*p = arg;
3610     typval_T	rettv;
3611 
3612     if (STRNCMP(p, "<SNR>", 5) == 0)
3613 	p = skipdigits(p + 5);
3614     p = to_name_end(p, TRUE);
3615     if (p == arg && *arg == '[')
3616     {
3617 
3618 	// Can be "[1, 2, 3]->Func()".
3619 	if (eval_list(&p, &rettv, NULL, FALSE) == FAIL)
3620 	    p = arg;
3621     }
3622     return p;
3623 }
3624 
3625 /*
3626  * parse a list: [expr, expr]
3627  * "*arg" points to the '['.
3628  * ppconst->pp_is_const is set if all items are a constant.
3629  */
3630     static int
3631 compile_list(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3632 {
3633     char_u	*p = skipwhite(*arg + 1);
3634     char_u	*whitep = *arg + 1;
3635     int		count = 0;
3636     int		is_const;
3637     int		is_all_const = TRUE;	// reset when non-const encountered
3638 
3639     for (;;)
3640     {
3641 	if (may_get_next_line(whitep, &p, cctx) == FAIL)
3642 	{
3643 	    semsg(_(e_list_end), *arg);
3644 	    return FAIL;
3645 	}
3646 	if (*p == ',')
3647 	{
3648 	    semsg(_(e_no_white_space_allowed_before_str_str), ",", p);
3649 	    return FAIL;
3650 	}
3651 	if (*p == ']')
3652 	{
3653 	    ++p;
3654 	    break;
3655 	}
3656 	if (compile_expr0_ext(&p, cctx, &is_const) == FAIL)
3657 	    return FAIL;
3658 	if (!is_const)
3659 	    is_all_const = FALSE;
3660 	++count;
3661 	if (*p == ',')
3662 	{
3663 	    ++p;
3664 	    if (*p != ']' && !IS_WHITE_OR_NUL(*p))
3665 	    {
3666 		semsg(_(e_white_space_required_after_str_str), ",", p - 1);
3667 		return FAIL;
3668 	    }
3669 	}
3670 	whitep = p;
3671 	p = skipwhite(p);
3672     }
3673     *arg = p;
3674 
3675     ppconst->pp_is_const = is_all_const;
3676     return generate_NEWLIST(cctx, count);
3677 }
3678 
3679 /*
3680  * Parse a lambda: "(arg, arg) => expr"
3681  * "*arg" points to the '('.
3682  * Returns OK/FAIL when a lambda is recognized, NOTDONE if it's not a lambda.
3683  */
3684     static int
3685 compile_lambda(char_u **arg, cctx_T *cctx)
3686 {
3687     int		r;
3688     typval_T	rettv;
3689     ufunc_T	*ufunc;
3690     evalarg_T	evalarg;
3691 
3692     CLEAR_FIELD(evalarg);
3693     evalarg.eval_flags = EVAL_EVALUATE;
3694     evalarg.eval_cctx = cctx;
3695 
3696     // Get the funcref in "rettv".
3697     r = get_lambda_tv(arg, &rettv, TRUE, &evalarg);
3698     if (r != OK)
3699     {
3700 	clear_evalarg(&evalarg, NULL);
3701 	return r;
3702     }
3703 
3704     // "rettv" will now be a partial referencing the function.
3705     ufunc = rettv.vval.v_partial->pt_func;
3706     ++ufunc->uf_refcount;
3707     clear_tv(&rettv);
3708 
3709     // Compile it here to get the return type.  The return type is optional,
3710     // when it's missing use t_unknown.  This is recognized in
3711     // compile_return().
3712     if (ufunc->uf_ret_type->tt_type == VAR_VOID)
3713 	ufunc->uf_ret_type = &t_unknown;
3714     compile_def_function(ufunc, FALSE, cctx->ctx_compile_type, cctx);
3715 
3716 #ifdef FEAT_PROFILE
3717     // When the outer function is compiled for profiling, the lambda may be
3718     // called without profiling.  Compile it here in the right context.
3719     if (cctx->ctx_compile_type == CT_PROFILE)
3720 	compile_def_function(ufunc, FALSE, CT_NONE, cctx);
3721 #endif
3722 
3723     // evalarg.eval_tofree_cmdline may have a copy of the last line and "*arg"
3724     // points into it.  Point to the original line to avoid a dangling pointer.
3725     if (evalarg.eval_tofree_cmdline != NULL)
3726     {
3727 	size_t	off = *arg - evalarg.eval_tofree_cmdline;
3728 
3729 	*arg = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum]
3730 									 + off;
3731     }
3732 
3733     clear_evalarg(&evalarg, NULL);
3734 
3735     if (ufunc->uf_def_status == UF_COMPILED)
3736     {
3737 	// The return type will now be known.
3738 	set_function_type(ufunc);
3739 
3740 	// The function reference count will be 1.  When the ISN_FUNCREF
3741 	// instruction is deleted the reference count is decremented and the
3742 	// function is freed.
3743 	return generate_FUNCREF(cctx, ufunc);
3744     }
3745 
3746     func_ptr_unref(ufunc);
3747     return FAIL;
3748 }
3749 
3750 /*
3751  * Get a lambda and compile it.  Uses Vim9 syntax.
3752  */
3753     int
3754 get_lambda_tv_and_compile(
3755 	char_u	    **arg,
3756 	typval_T    *rettv,
3757 	int	    types_optional,
3758 	evalarg_T   *evalarg)
3759 {
3760     int		r;
3761     ufunc_T	*ufunc;
3762     int		save_sc_version = current_sctx.sc_version;
3763 
3764     // Get the funcref in "rettv".
3765     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
3766     r = get_lambda_tv(arg, rettv, types_optional, evalarg);
3767     current_sctx.sc_version = save_sc_version;
3768     if (r != OK)
3769 	return r;
3770 
3771     // "rettv" will now be a partial referencing the function.
3772     ufunc = rettv->vval.v_partial->pt_func;
3773 
3774     // Compile it here to get the return type.  The return type is optional,
3775     // when it's missing use t_unknown.  This is recognized in
3776     // compile_return().
3777     if (ufunc->uf_ret_type == NULL || ufunc->uf_ret_type->tt_type == VAR_VOID)
3778 	ufunc->uf_ret_type = &t_unknown;
3779     compile_def_function(ufunc, FALSE, CT_NONE, NULL);
3780 
3781     if (ufunc->uf_def_status == UF_COMPILED)
3782     {
3783 	// The return type will now be known.
3784 	set_function_type(ufunc);
3785 	return OK;
3786     }
3787     clear_tv(rettv);
3788     return FAIL;
3789 }
3790 
3791 /*
3792  * parse a dict: {key: val, [key]: val}
3793  * "*arg" points to the '{'.
3794  * ppconst->pp_is_const is set if all item values are a constant.
3795  */
3796     static int
3797 compile_dict(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3798 {
3799     garray_T	*instr = &cctx->ctx_instr;
3800     int		count = 0;
3801     dict_T	*d = dict_alloc();
3802     dictitem_T	*item;
3803     char_u	*whitep = *arg + 1;
3804     char_u	*p;
3805     int		is_const;
3806     int		is_all_const = TRUE;	// reset when non-const encountered
3807 
3808     if (d == NULL)
3809 	return FAIL;
3810     if (generate_ppconst(cctx, ppconst) == FAIL)
3811 	return FAIL;
3812     for (;;)
3813     {
3814 	char_u	    *key = NULL;
3815 
3816 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
3817 	{
3818 	    *arg = NULL;
3819 	    goto failret;
3820 	}
3821 
3822 	if (**arg == '}')
3823 	    break;
3824 
3825 	if (**arg == '[')
3826 	{
3827 	    isn_T	*isn;
3828 
3829 	    // {[expr]: value} uses an evaluated key.
3830 	    *arg = skipwhite(*arg + 1);
3831 	    if (compile_expr0(arg, cctx) == FAIL)
3832 		return FAIL;
3833 	    isn = ((isn_T *)instr->ga_data) + instr->ga_len - 1;
3834 	    if (isn->isn_type == ISN_PUSHNR)
3835 	    {
3836 		char buf[NUMBUFLEN];
3837 
3838 		// Convert to string at compile time.
3839 		vim_snprintf(buf, NUMBUFLEN, "%lld", isn->isn_arg.number);
3840 		isn->isn_type = ISN_PUSHS;
3841 		isn->isn_arg.string = vim_strsave((char_u *)buf);
3842 	    }
3843 	    if (isn->isn_type == ISN_PUSHS)
3844 		key = isn->isn_arg.string;
3845 	    else if (may_generate_2STRING(-1, FALSE, cctx) == FAIL)
3846 		return FAIL;
3847 	    *arg = skipwhite(*arg);
3848 	    if (**arg != ']')
3849 	    {
3850 		emsg(_(e_missing_matching_bracket_after_dict_key));
3851 		return FAIL;
3852 	    }
3853 	    ++*arg;
3854 	}
3855 	else
3856 	{
3857 	    // {"name": value},
3858 	    // {'name': value},
3859 	    // {name: value} use "name" as a literal key
3860 	    key = get_literal_key(arg);
3861 	    if (key == NULL)
3862 		return FAIL;
3863 	    if (generate_PUSHS(cctx, &key) == FAIL)
3864 		return FAIL;
3865 	}
3866 
3867 	// Check for duplicate keys, if using string keys.
3868 	if (key != NULL)
3869 	{
3870 	    item = dict_find(d, key, -1);
3871 	    if (item != NULL)
3872 	    {
3873 		semsg(_(e_duplicate_key), key);
3874 		goto failret;
3875 	    }
3876 	    item = dictitem_alloc(key);
3877 	    if (item != NULL)
3878 	    {
3879 		item->di_tv.v_type = VAR_UNKNOWN;
3880 		item->di_tv.v_lock = 0;
3881 		if (dict_add(d, item) == FAIL)
3882 		    dictitem_free(item);
3883 	    }
3884 	}
3885 
3886 	if (**arg != ':')
3887 	{
3888 	    if (*skipwhite(*arg) == ':')
3889 		semsg(_(e_no_white_space_allowed_before_str_str), ":", *arg);
3890 	    else
3891 		semsg(_(e_missing_dict_colon), *arg);
3892 	    return FAIL;
3893 	}
3894 	whitep = *arg + 1;
3895 	if (!IS_WHITE_OR_NUL(*whitep))
3896 	{
3897 	    semsg(_(e_white_space_required_after_str_str), ":", *arg);
3898 	    return FAIL;
3899 	}
3900 
3901 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
3902 	{
3903 	    *arg = NULL;
3904 	    goto failret;
3905 	}
3906 
3907 	if (compile_expr0_ext(arg, cctx, &is_const) == FAIL)
3908 	    return FAIL;
3909 	if (!is_const)
3910 	    is_all_const = FALSE;
3911 	++count;
3912 
3913 	whitep = *arg;
3914 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
3915 	{
3916 	    *arg = NULL;
3917 	    goto failret;
3918 	}
3919 	if (**arg == '}')
3920 	    break;
3921 	if (**arg != ',')
3922 	{
3923 	    semsg(_(e_missing_dict_comma), *arg);
3924 	    goto failret;
3925 	}
3926 	if (IS_WHITE_OR_NUL(*whitep))
3927 	{
3928 	    semsg(_(e_no_white_space_allowed_before_str_str), ",", whitep);
3929 	    return FAIL;
3930 	}
3931 	whitep = *arg + 1;
3932 	if (!IS_WHITE_OR_NUL(*whitep))
3933 	{
3934 	    semsg(_(e_white_space_required_after_str_str), ",", *arg);
3935 	    return FAIL;
3936 	}
3937 	*arg = skipwhite(whitep);
3938     }
3939 
3940     *arg = *arg + 1;
3941 
3942     // Allow for following comment, after at least one space.
3943     p = skipwhite(*arg);
3944     if (VIM_ISWHITE(**arg) && vim9_comment_start(p))
3945 	*arg += STRLEN(*arg);
3946 
3947     dict_unref(d);
3948     ppconst->pp_is_const = is_all_const;
3949     return generate_NEWDICT(cctx, count);
3950 
3951 failret:
3952     if (*arg == NULL)
3953     {
3954 	semsg(_(e_missing_dict_end), _("[end of lines]"));
3955 	*arg = (char_u *)"";
3956     }
3957     dict_unref(d);
3958     return FAIL;
3959 }
3960 
3961 /*
3962  * Compile "&option".
3963  */
3964     static int
3965 compile_get_option(char_u **arg, cctx_T *cctx)
3966 {
3967     typval_T	rettv;
3968     char_u	*start = *arg;
3969     int		ret;
3970 
3971     // parse the option and get the current value to get the type.
3972     rettv.v_type = VAR_UNKNOWN;
3973     ret = eval_option(arg, &rettv, TRUE);
3974     if (ret == OK)
3975     {
3976 	// include the '&' in the name, eval_option() expects it.
3977 	char_u	*name = vim_strnsave(start, *arg - start);
3978 	type_T	*type = rettv.v_type == VAR_BOOL ? &t_bool
3979 			  : rettv.v_type == VAR_NUMBER ? &t_number : &t_string;
3980 
3981 	ret = generate_LOAD(cctx, ISN_LOADOPT, 0, name, type);
3982 	vim_free(name);
3983     }
3984     clear_tv(&rettv);
3985 
3986     return ret;
3987 }
3988 
3989 /*
3990  * Compile "$VAR".
3991  */
3992     static int
3993 compile_get_env(char_u **arg, cctx_T *cctx)
3994 {
3995     char_u	*start = *arg;
3996     int		len;
3997     int		ret;
3998     char_u	*name;
3999 
4000     ++*arg;
4001     len = get_env_len(arg);
4002     if (len == 0)
4003     {
4004 	semsg(_(e_syntax_error_at_str), start - 1);
4005 	return FAIL;
4006     }
4007 
4008     // include the '$' in the name, eval_env_var() expects it.
4009     name = vim_strnsave(start, len + 1);
4010     ret = generate_LOAD(cctx, ISN_LOADENV, 0, name, &t_string);
4011     vim_free(name);
4012     return ret;
4013 }
4014 
4015 /*
4016  * Compile "@r".
4017  */
4018     static int
4019 compile_get_register(char_u **arg, cctx_T *cctx)
4020 {
4021     int		ret;
4022 
4023     ++*arg;
4024     if (**arg == NUL)
4025     {
4026 	semsg(_(e_syntax_error_at_str), *arg - 1);
4027 	return FAIL;
4028     }
4029     if (!valid_yank_reg(**arg, FALSE))
4030     {
4031 	emsg_invreg(**arg);
4032 	return FAIL;
4033     }
4034     ret = generate_LOAD(cctx, ISN_LOADREG, **arg, NULL, &t_string);
4035     ++*arg;
4036     return ret;
4037 }
4038 
4039 /*
4040  * Apply leading '!', '-' and '+' to constant "rettv".
4041  * When "numeric_only" is TRUE do not apply '!'.
4042  */
4043     static int
4044 apply_leader(typval_T *rettv, int numeric_only, char_u *start, char_u **end)
4045 {
4046     char_u *p = *end;
4047 
4048     // this works from end to start
4049     while (p > start)
4050     {
4051 	--p;
4052 	if (*p == '-' || *p == '+')
4053 	{
4054 	    // only '-' has an effect, for '+' we only check the type
4055 #ifdef FEAT_FLOAT
4056 	    if (rettv->v_type == VAR_FLOAT)
4057 	    {
4058 		if (*p == '-')
4059 		    rettv->vval.v_float = -rettv->vval.v_float;
4060 	    }
4061 	    else
4062 #endif
4063 	    {
4064 		varnumber_T	val;
4065 		int		error = FALSE;
4066 
4067 		// tv_get_number_chk() accepts a string, but we don't want that
4068 		// here
4069 		if (check_not_string(rettv) == FAIL)
4070 		    return FAIL;
4071 		val = tv_get_number_chk(rettv, &error);
4072 		clear_tv(rettv);
4073 		if (error)
4074 		    return FAIL;
4075 		if (*p == '-')
4076 		    val = -val;
4077 		rettv->v_type = VAR_NUMBER;
4078 		rettv->vval.v_number = val;
4079 	    }
4080 	}
4081 	else if (numeric_only)
4082 	{
4083 	    ++p;
4084 	    break;
4085 	}
4086 	else if (*p == '!')
4087 	{
4088 	    int v = tv2bool(rettv);
4089 
4090 	    // '!' is permissive in the type.
4091 	    clear_tv(rettv);
4092 	    rettv->v_type = VAR_BOOL;
4093 	    rettv->vval.v_number = v ? VVAL_FALSE : VVAL_TRUE;
4094 	}
4095     }
4096     *end = p;
4097     return OK;
4098 }
4099 
4100 /*
4101  * Recognize v: variables that are constants and set "rettv".
4102  */
4103     static void
4104 get_vim_constant(char_u **arg, typval_T *rettv)
4105 {
4106     if (STRNCMP(*arg, "v:true", 6) == 0)
4107     {
4108 	rettv->v_type = VAR_BOOL;
4109 	rettv->vval.v_number = VVAL_TRUE;
4110 	*arg += 6;
4111     }
4112     else if (STRNCMP(*arg, "v:false", 7) == 0)
4113     {
4114 	rettv->v_type = VAR_BOOL;
4115 	rettv->vval.v_number = VVAL_FALSE;
4116 	*arg += 7;
4117     }
4118     else if (STRNCMP(*arg, "v:null", 6) == 0)
4119     {
4120 	rettv->v_type = VAR_SPECIAL;
4121 	rettv->vval.v_number = VVAL_NULL;
4122 	*arg += 6;
4123     }
4124     else if (STRNCMP(*arg, "v:none", 6) == 0)
4125     {
4126 	rettv->v_type = VAR_SPECIAL;
4127 	rettv->vval.v_number = VVAL_NONE;
4128 	*arg += 6;
4129     }
4130 }
4131 
4132     exprtype_T
4133 get_compare_type(char_u *p, int *len, int *type_is)
4134 {
4135     exprtype_T	type = EXPR_UNKNOWN;
4136     int		i;
4137 
4138     switch (p[0])
4139     {
4140 	case '=':   if (p[1] == '=')
4141 			type = EXPR_EQUAL;
4142 		    else if (p[1] == '~')
4143 			type = EXPR_MATCH;
4144 		    break;
4145 	case '!':   if (p[1] == '=')
4146 			type = EXPR_NEQUAL;
4147 		    else if (p[1] == '~')
4148 			type = EXPR_NOMATCH;
4149 		    break;
4150 	case '>':   if (p[1] != '=')
4151 		    {
4152 			type = EXPR_GREATER;
4153 			*len = 1;
4154 		    }
4155 		    else
4156 			type = EXPR_GEQUAL;
4157 		    break;
4158 	case '<':   if (p[1] != '=')
4159 		    {
4160 			type = EXPR_SMALLER;
4161 			*len = 1;
4162 		    }
4163 		    else
4164 			type = EXPR_SEQUAL;
4165 		    break;
4166 	case 'i':   if (p[1] == 's')
4167 		    {
4168 			// "is" and "isnot"; but not a prefix of a name
4169 			if (p[2] == 'n' && p[3] == 'o' && p[4] == 't')
4170 			    *len = 5;
4171 			i = p[*len];
4172 			if (!isalnum(i) && i != '_')
4173 			{
4174 			    type = *len == 2 ? EXPR_IS : EXPR_ISNOT;
4175 			    *type_is = TRUE;
4176 			}
4177 		    }
4178 		    break;
4179     }
4180     return type;
4181 }
4182 
4183 /*
4184  * Skip over an expression, ignoring most errors.
4185  */
4186     static void
4187 skip_expr_cctx(char_u **arg, cctx_T *cctx)
4188 {
4189     evalarg_T	evalarg;
4190 
4191     CLEAR_FIELD(evalarg);
4192     evalarg.eval_cctx = cctx;
4193     skip_expr(arg, &evalarg);
4194 }
4195 
4196 /*
4197  * Compile code to apply '-', '+' and '!'.
4198  * When "numeric_only" is TRUE do not apply '!'.
4199  */
4200     static int
4201 compile_leader(cctx_T *cctx, int numeric_only, char_u *start, char_u **end)
4202 {
4203     char_u	*p = *end;
4204 
4205     // this works from end to start
4206     while (p > start)
4207     {
4208 	--p;
4209 	while (VIM_ISWHITE(*p))
4210 	    --p;
4211 	if (*p == '-' || *p == '+')
4212 	{
4213 	    int	    negate = *p == '-';
4214 	    isn_T   *isn;
4215 
4216 	    // TODO: check type
4217 	    while (p > start && (p[-1] == '-' || p[-1] == '+'))
4218 	    {
4219 		--p;
4220 		if (*p == '-')
4221 		    negate = !negate;
4222 	    }
4223 	    // only '-' has an effect, for '+' we only check the type
4224 	    if (negate)
4225 		isn = generate_instr(cctx, ISN_NEGATENR);
4226 	    else
4227 		isn = generate_instr(cctx, ISN_CHECKNR);
4228 	    if (isn == NULL)
4229 		return FAIL;
4230 	}
4231 	else if (numeric_only)
4232 	{
4233 	    ++p;
4234 	    break;
4235 	}
4236 	else
4237 	{
4238 	    int  invert = *p == '!';
4239 
4240 	    while (p > start && (p[-1] == '!' || VIM_ISWHITE(p[-1])))
4241 	    {
4242 		if (p[-1] == '!')
4243 		    invert = !invert;
4244 		--p;
4245 	    }
4246 	    if (generate_2BOOL(cctx, invert, -1) == FAIL)
4247 		return FAIL;
4248 	}
4249     }
4250     *end = p;
4251     return OK;
4252 }
4253 
4254 /*
4255  * Compile "(expression)": recursive!
4256  * Return FAIL/OK.
4257  */
4258     static int
4259 compile_parenthesis(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4260 {
4261     int	    ret;
4262     char_u  *p = *arg + 1;
4263 
4264     if (may_get_next_line_error(p, arg, cctx) == FAIL)
4265 	return FAIL;
4266     if (ppconst->pp_used <= PPSIZE - 10)
4267     {
4268 	ret = compile_expr1(arg, cctx, ppconst);
4269     }
4270     else
4271     {
4272 	// Not enough space in ppconst, flush constants.
4273 	if (generate_ppconst(cctx, ppconst) == FAIL)
4274 	    return FAIL;
4275 	ret = compile_expr0(arg, cctx);
4276     }
4277     if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4278 	return FAIL;
4279     if (**arg == ')')
4280 	++*arg;
4281     else if (ret == OK)
4282     {
4283 	emsg(_(e_missing_close));
4284 	ret = FAIL;
4285     }
4286     return ret;
4287 }
4288 
4289 /*
4290  * Compile whatever comes after "name" or "name()".
4291  * Advances "*arg" only when something was recognized.
4292  */
4293     static int
4294 compile_subscript(
4295 	char_u **arg,
4296 	cctx_T *cctx,
4297 	char_u *start_leader,
4298 	char_u **end_leader,
4299 	ppconst_T *ppconst)
4300 {
4301     char_u	*name_start = *end_leader;
4302 
4303     for (;;)
4304     {
4305 	char_u *p = skipwhite(*arg);
4306 
4307 	if (*p == NUL || (VIM_ISWHITE(**arg) && vim9_comment_start(p)))
4308 	{
4309 	    char_u *next = peek_next_line_from_context(cctx);
4310 
4311 	    // If a following line starts with "->{" or "->X" advance to that
4312 	    // line, so that a line break before "->" is allowed.
4313 	    // Also if a following line starts with ".x".
4314 	    if (next != NULL &&
4315 		    ((next[0] == '-' && next[1] == '>'
4316 				 && (next[2] == '{'
4317 				       || ASCII_ISALPHA(*skipwhite(next + 2))))
4318 		    || (next[0] == '.' && eval_isdictc(next[1]))))
4319 	    {
4320 		next = next_line_from_context(cctx, TRUE);
4321 		if (next == NULL)
4322 		    return FAIL;
4323 		*arg = next;
4324 		p = skipwhite(*arg);
4325 	    }
4326 	}
4327 
4328 	// Do not skip over white space to find the "(", "execute 'x' (expr)"
4329 	// is not a function call.
4330 	if (**arg == '(')
4331 	{
4332 	    garray_T    *stack = &cctx->ctx_type_stack;
4333 	    type_T	*type;
4334 	    int		argcount = 0;
4335 
4336 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4337 		return FAIL;
4338 	    ppconst->pp_is_const = FALSE;
4339 
4340 	    // funcref(arg)
4341 	    type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4342 
4343 	    *arg = skipwhite(p + 1);
4344 	    if (compile_arguments(arg, cctx, &argcount, FALSE) == FAIL)
4345 		return FAIL;
4346 	    if (generate_PCALL(cctx, argcount, name_start, type, TRUE) == FAIL)
4347 		return FAIL;
4348 	}
4349 	else if (*p == '-' && p[1] == '>')
4350 	{
4351 	    char_u *pstart = p;
4352 
4353 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4354 		return FAIL;
4355 	    ppconst->pp_is_const = FALSE;
4356 
4357 	    // something->method()
4358 	    // Apply the '!', '-' and '+' first:
4359 	    //   -1.0->func() works like (-1.0)->func()
4360 	    if (compile_leader(cctx, TRUE, start_leader, end_leader) == FAIL)
4361 		return FAIL;
4362 
4363 	    p += 2;
4364 	    *arg = skipwhite(p);
4365 	    // No line break supported right after "->".
4366 	    if (**arg == '(')
4367 	    {
4368 		int	    argcount = 1;
4369 		garray_T    *stack = &cctx->ctx_type_stack;
4370 		int	    type_idx_start = stack->ga_len;
4371 		type_T	    *type;
4372 		int	    expr_isn_start = cctx->ctx_instr.ga_len;
4373 		int	    expr_isn_end;
4374 		int	    arg_isn_count;
4375 
4376 		// Funcref call:  list->(Refs[2])(arg)
4377 		// or lambda:	  list->((arg) => expr)(arg)
4378 		//
4379 		// Fist compile the function expression.
4380 		if (compile_parenthesis(arg, cctx, ppconst) == FAIL)
4381 		    return FAIL;
4382 
4383 		// Remember the next instruction index, where the instructions
4384 		// for arguments are being written.
4385 		expr_isn_end = cctx->ctx_instr.ga_len;
4386 
4387 		// Compile the arguments.
4388 		if (**arg != '(')
4389 		{
4390 		    if (*skipwhite(*arg) == '(')
4391 			emsg(_(e_nowhitespace));
4392 		    else
4393 			semsg(_(e_missing_paren), *arg);
4394 		    return FAIL;
4395 		}
4396 		*arg = skipwhite(*arg + 1);
4397 		if (compile_arguments(arg, cctx, &argcount, FALSE) == FAIL)
4398 		    return FAIL;
4399 
4400 		// Move the instructions for the arguments to before the
4401 		// instructions of the expression and move the type of the
4402 		// expression after the argument types.  This is what ISN_PCALL
4403 		// expects.
4404 		stack = &cctx->ctx_type_stack;
4405 		arg_isn_count = cctx->ctx_instr.ga_len - expr_isn_end;
4406 		if (arg_isn_count > 0)
4407 		{
4408 		    int	    expr_isn_count = expr_isn_end - expr_isn_start;
4409 		    isn_T   *isn = ALLOC_MULT(isn_T, expr_isn_count);
4410 
4411 		    if (isn == NULL)
4412 			return FAIL;
4413 		    mch_memmove(isn, ((isn_T *)cctx->ctx_instr.ga_data)
4414 							      + expr_isn_start,
4415 					       sizeof(isn_T) * expr_isn_count);
4416 		    mch_memmove(((isn_T *)cctx->ctx_instr.ga_data)
4417 							      + expr_isn_start,
4418 			     ((isn_T *)cctx->ctx_instr.ga_data) + expr_isn_end,
4419 						sizeof(isn_T) * arg_isn_count);
4420 		    mch_memmove(((isn_T *)cctx->ctx_instr.ga_data)
4421 					      + expr_isn_start + arg_isn_count,
4422 					  isn, sizeof(isn_T) * expr_isn_count);
4423 		    vim_free(isn);
4424 
4425 		    type = ((type_T **)stack->ga_data)[type_idx_start];
4426 		    mch_memmove(((type_T **)stack->ga_data) + type_idx_start,
4427 			      ((type_T **)stack->ga_data) + type_idx_start + 1,
4428 			      sizeof(type_T *)
4429 				       * (stack->ga_len - type_idx_start - 1));
4430 		    ((type_T **)stack->ga_data)[stack->ga_len - 1] = type;
4431 		}
4432 
4433 		type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4434 		if (generate_PCALL(cctx, argcount, p - 2, type, FALSE) == FAIL)
4435 		    return FAIL;
4436 	    }
4437 	    else
4438 	    {
4439 		// method call:  list->method()
4440 		p = *arg;
4441 		if (!eval_isnamec1(*p))
4442 		{
4443 		    semsg(_(e_trailing_arg), pstart);
4444 		    return FAIL;
4445 		}
4446 		if (ASCII_ISALPHA(*p) && p[1] == ':')
4447 		    p += 2;
4448 		for ( ; eval_isnamec(*p); ++p)
4449 		    ;
4450 		if (*p != '(')
4451 		{
4452 		    semsg(_(e_missing_paren), *arg);
4453 		    return FAIL;
4454 		}
4455 		if (compile_call(arg, p - *arg, cctx, ppconst, 1) == FAIL)
4456 		    return FAIL;
4457 	    }
4458 	}
4459 	else if (**arg == '[')
4460 	{
4461 	    int		is_slice = FALSE;
4462 
4463 	    // list index: list[123]
4464 	    // dict member: dict[key]
4465 	    // string index: text[123]
4466 	    // blob index: blob[123]
4467 	    // TODO: more arguments
4468 	    // TODO: recognize list or dict at runtime
4469 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4470 		return FAIL;
4471 	    ppconst->pp_is_const = FALSE;
4472 
4473 	    ++p;
4474 	    if (may_get_next_line_error(p, arg, cctx) == FAIL)
4475 		return FAIL;
4476 	    if (**arg == ':')
4477 	    {
4478 		// missing first index is equal to zero
4479 		generate_PUSHNR(cctx, 0);
4480 	    }
4481 	    else
4482 	    {
4483 		if (compile_expr0(arg, cctx) == FAIL)
4484 		    return FAIL;
4485 		if (**arg == ':')
4486 		{
4487 		    semsg(_(e_white_space_required_before_and_after_str_at_str),
4488 								    ":", *arg);
4489 		    return FAIL;
4490 		}
4491 		if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4492 		    return FAIL;
4493 		*arg = skipwhite(*arg);
4494 	    }
4495 	    if (**arg == ':')
4496 	    {
4497 		is_slice = TRUE;
4498 		++*arg;
4499 		if (!IS_WHITE_OR_NUL(**arg) && **arg != ']')
4500 		{
4501 		    semsg(_(e_white_space_required_before_and_after_str_at_str),
4502 								    ":", *arg);
4503 		    return FAIL;
4504 		}
4505 		if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4506 		    return FAIL;
4507 		if (**arg == ']')
4508 		    // missing second index is equal to end of string
4509 		    generate_PUSHNR(cctx, -1);
4510 		else
4511 		{
4512 		    if (compile_expr0(arg, cctx) == FAIL)
4513 			return FAIL;
4514 		    if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4515 			return FAIL;
4516 		    *arg = skipwhite(*arg);
4517 		}
4518 	    }
4519 
4520 	    if (**arg != ']')
4521 	    {
4522 		emsg(_(e_missbrac));
4523 		return FAIL;
4524 	    }
4525 	    *arg = *arg + 1;
4526 
4527 	    if (compile_member(is_slice, cctx) == FAIL)
4528 		return FAIL;
4529 	}
4530 	else if (*p == '.' && p[1] != '.')
4531 	{
4532 	    // dictionary member: dict.name
4533 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4534 		return FAIL;
4535 	    ppconst->pp_is_const = FALSE;
4536 
4537 	    *arg = p + 1;
4538 	    if (IS_WHITE_OR_NUL(**arg))
4539 	    {
4540 		emsg(_(e_missing_name_after_dot));
4541 		return FAIL;
4542 	    }
4543 	    p = *arg;
4544 	    if (eval_isdictc(*p))
4545 		while (eval_isnamec(*p))
4546 		    MB_PTR_ADV(p);
4547 	    if (p == *arg)
4548 	    {
4549 		semsg(_(e_syntax_error_at_str), *arg);
4550 		return FAIL;
4551 	    }
4552 	    if (generate_STRINGMEMBER(cctx, *arg, p - *arg) == FAIL)
4553 		return FAIL;
4554 	    *arg = p;
4555 	}
4556 	else
4557 	    break;
4558     }
4559 
4560     // TODO - see handle_subscript():
4561     // Turn "dict.Func" into a partial for "Func" bound to "dict".
4562     // Don't do this when "Func" is already a partial that was bound
4563     // explicitly (pt_auto is FALSE).
4564 
4565     return OK;
4566 }
4567 
4568 /*
4569  * Compile an expression at "*arg" and add instructions to "cctx->ctx_instr".
4570  * "arg" is advanced until after the expression, skipping white space.
4571  *
4572  * If the value is a constant "ppconst->pp_used" will be non-zero.
4573  * Before instructions are generated, any values in "ppconst" will generated.
4574  *
4575  * This is the compiling equivalent of eval1(), eval2(), etc.
4576  */
4577 
4578 /*
4579  *  number		number constant
4580  *  0zFFFFFFFF		Blob constant
4581  *  "string"		string constant
4582  *  'string'		literal string constant
4583  *  &option-name	option value
4584  *  @r			register contents
4585  *  identifier		variable value
4586  *  function()		function call
4587  *  $VAR		environment variable
4588  *  (expression)	nested expression
4589  *  [expr, expr]	List
4590  *  {key: val, [key]: val}   Dictionary
4591  *
4592  *  Also handle:
4593  *  ! in front		logical NOT
4594  *  - in front		unary minus
4595  *  + in front		unary plus (ignored)
4596  *  trailing (arg)	funcref/partial call
4597  *  trailing []		subscript in String or List
4598  *  trailing .name	entry in Dictionary
4599  *  trailing ->name()	method call
4600  */
4601     static int
4602 compile_expr7(
4603 	char_u **arg,
4604 	cctx_T *cctx,
4605 	ppconst_T *ppconst)
4606 {
4607     char_u	*start_leader, *end_leader;
4608     int		ret = OK;
4609     typval_T	*rettv = &ppconst->pp_tv[ppconst->pp_used];
4610     int		used_before = ppconst->pp_used;
4611 
4612     ppconst->pp_is_const = FALSE;
4613 
4614     /*
4615      * Skip '!', '-' and '+' characters.  They are handled later.
4616      */
4617     start_leader = *arg;
4618     if (eval_leader(arg, TRUE) == FAIL)
4619 	return FAIL;
4620     end_leader = *arg;
4621 
4622     rettv->v_type = VAR_UNKNOWN;
4623     switch (**arg)
4624     {
4625 	/*
4626 	 * Number constant.
4627 	 */
4628 	case '0':	// also for blob starting with 0z
4629 	case '1':
4630 	case '2':
4631 	case '3':
4632 	case '4':
4633 	case '5':
4634 	case '6':
4635 	case '7':
4636 	case '8':
4637 	case '9':
4638 	case '.':   if (eval_number(arg, rettv, TRUE, FALSE) == FAIL)
4639 			return FAIL;
4640 		    // Apply "-" and "+" just before the number now, right to
4641 		    // left.  Matters especially when "->" follows.  Stops at
4642 		    // '!'.
4643 		    if (apply_leader(rettv, TRUE,
4644 					    start_leader, &end_leader) == FAIL)
4645 		    {
4646 			clear_tv(rettv);
4647 			return FAIL;
4648 		    }
4649 		    break;
4650 
4651 	/*
4652 	 * String constant: "string".
4653 	 */
4654 	case '"':   if (eval_string(arg, rettv, TRUE) == FAIL)
4655 			return FAIL;
4656 		    break;
4657 
4658 	/*
4659 	 * Literal string constant: 'str''ing'.
4660 	 */
4661 	case '\'':  if (eval_lit_string(arg, rettv, TRUE) == FAIL)
4662 			return FAIL;
4663 		    break;
4664 
4665 	/*
4666 	 * Constant Vim variable.
4667 	 */
4668 	case 'v':   get_vim_constant(arg, rettv);
4669 		    ret = NOTDONE;
4670 		    break;
4671 
4672 	/*
4673 	 * "true" constant
4674 	 */
4675 	case 't':   if (STRNCMP(*arg, "true", 4) == 0
4676 						   && !eval_isnamec((*arg)[4]))
4677 		    {
4678 			*arg += 4;
4679 			rettv->v_type = VAR_BOOL;
4680 			rettv->vval.v_number = VVAL_TRUE;
4681 		    }
4682 		    else
4683 			ret = NOTDONE;
4684 		    break;
4685 
4686 	/*
4687 	 * "false" constant
4688 	 */
4689 	case 'f':   if (STRNCMP(*arg, "false", 5) == 0
4690 						   && !eval_isnamec((*arg)[5]))
4691 		    {
4692 			*arg += 5;
4693 			rettv->v_type = VAR_BOOL;
4694 			rettv->vval.v_number = VVAL_FALSE;
4695 		    }
4696 		    else
4697 			ret = NOTDONE;
4698 		    break;
4699 
4700 	/*
4701 	 * "null" constant
4702 	 */
4703 	case 'n':   if (STRNCMP(*arg, "null", 4) == 0
4704 						   && !eval_isnamec((*arg)[4]))
4705 		    {
4706 			*arg += 4;
4707 			rettv->v_type = VAR_SPECIAL;
4708 			rettv->vval.v_number = VVAL_NULL;
4709 		    }
4710 		    else
4711 			ret = NOTDONE;
4712 		    break;
4713 
4714 	/*
4715 	 * List: [expr, expr]
4716 	 */
4717 	case '[':   if (generate_ppconst(cctx, ppconst) == FAIL)
4718 			return FAIL;
4719 		    ret = compile_list(arg, cctx, ppconst);
4720 		    break;
4721 
4722 	/*
4723 	 * Dictionary: {'key': val, 'key': val}
4724 	 */
4725 	case '{':   if (generate_ppconst(cctx, ppconst) == FAIL)
4726 			return FAIL;
4727 		    ret = compile_dict(arg, cctx, ppconst);
4728 		    break;
4729 
4730 	/*
4731 	 * Option value: &name
4732 	 */
4733 	case '&':	if (generate_ppconst(cctx, ppconst) == FAIL)
4734 			    return FAIL;
4735 			ret = compile_get_option(arg, cctx);
4736 			break;
4737 
4738 	/*
4739 	 * Environment variable: $VAR.
4740 	 */
4741 	case '$':	if (generate_ppconst(cctx, ppconst) == FAIL)
4742 			    return FAIL;
4743 			ret = compile_get_env(arg, cctx);
4744 			break;
4745 
4746 	/*
4747 	 * Register contents: @r.
4748 	 */
4749 	case '@':	if (generate_ppconst(cctx, ppconst) == FAIL)
4750 			    return FAIL;
4751 			ret = compile_get_register(arg, cctx);
4752 			break;
4753 	/*
4754 	 * nested expression: (expression).
4755 	 * lambda: (arg, arg) => expr
4756 	 * funcref: (arg, arg) => { statement }
4757 	 */
4758 	case '(':   // if compile_lambda returns NOTDONE then it must be (expr)
4759 		    ret = compile_lambda(arg, cctx);
4760 		    if (ret == NOTDONE)
4761 			ret = compile_parenthesis(arg, cctx, ppconst);
4762 		    break;
4763 
4764 	default:    ret = NOTDONE;
4765 		    break;
4766     }
4767     if (ret == FAIL)
4768 	return FAIL;
4769 
4770     if (rettv->v_type != VAR_UNKNOWN && used_before == ppconst->pp_used)
4771     {
4772 	if (cctx->ctx_skip == SKIP_YES)
4773 	    clear_tv(rettv);
4774 	else
4775 	    // A constant expression can possibly be handled compile time,
4776 	    // return the value instead of generating code.
4777 	    ++ppconst->pp_used;
4778     }
4779     else if (ret == NOTDONE)
4780     {
4781 	char_u	    *p;
4782 	int	    r;
4783 
4784 	if (!eval_isnamec1(**arg))
4785 	{
4786 	    if (!vim9_bad_comment(*arg))
4787 	    {
4788 		if (ends_excmd(*skipwhite(*arg)))
4789 		    semsg(_(e_empty_expression_str), *arg);
4790 		else
4791 		    semsg(_(e_name_expected_str), *arg);
4792 	    }
4793 	    return FAIL;
4794 	}
4795 
4796 	// "name" or "name()"
4797 	p = to_name_end(*arg, TRUE);
4798 	if (p - *arg == (size_t)1 && **arg == '_')
4799 	{
4800 	    emsg(_(e_cannot_use_underscore_here));
4801 	    return FAIL;
4802 	}
4803 
4804 	if (*p == '(')
4805 	{
4806 	    r = compile_call(arg, p - *arg, cctx, ppconst, 0);
4807 	}
4808 	else
4809 	{
4810 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4811 		return FAIL;
4812 	    r = compile_load(arg, p, cctx, TRUE, TRUE);
4813 	}
4814 	if (r == FAIL)
4815 	    return FAIL;
4816     }
4817 
4818     // Handle following "[]", ".member", etc.
4819     // Then deal with prefixed '-', '+' and '!', if not done already.
4820     if (compile_subscript(arg, cctx, start_leader, &end_leader,
4821 							     ppconst) == FAIL)
4822 	return FAIL;
4823     if (ppconst->pp_used > 0)
4824     {
4825 	// apply the '!', '-' and '+' before the constant
4826 	rettv = &ppconst->pp_tv[ppconst->pp_used - 1];
4827 	if (apply_leader(rettv, FALSE, start_leader, &end_leader) == FAIL)
4828 	    return FAIL;
4829 	return OK;
4830     }
4831     if (compile_leader(cctx, FALSE, start_leader, &end_leader) == FAIL)
4832 	return FAIL;
4833     return OK;
4834 }
4835 
4836 /*
4837  * Give the "white on both sides" error, taking the operator from "p[len]".
4838  */
4839     void
4840 error_white_both(char_u *op, int len)
4841 {
4842     char_u	buf[10];
4843 
4844     vim_strncpy(buf, op, len);
4845     semsg(_(e_white_space_required_before_and_after_str_at_str), buf, op);
4846 }
4847 
4848 /*
4849  * <type>expr7: runtime type check / conversion
4850  */
4851     static int
4852 compile_expr7t(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4853 {
4854     type_T *want_type = NULL;
4855 
4856     // Recognize <type>
4857     if (**arg == '<' && eval_isnamec1((*arg)[1]))
4858     {
4859 	++*arg;
4860 	want_type = parse_type(arg, cctx->ctx_type_list, TRUE);
4861 	if (want_type == NULL)
4862 	    return FAIL;
4863 
4864 	if (**arg != '>')
4865 	{
4866 	    if (*skipwhite(*arg) == '>')
4867 		semsg(_(e_no_white_space_allowed_before_str_str), ">", *arg);
4868 	    else
4869 		emsg(_(e_missing_gt));
4870 	    return FAIL;
4871 	}
4872 	++*arg;
4873 	if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4874 	    return FAIL;
4875     }
4876 
4877     if (compile_expr7(arg, cctx, ppconst) == FAIL)
4878 	return FAIL;
4879 
4880     if (want_type != NULL)
4881     {
4882 	garray_T    *stack = &cctx->ctx_type_stack;
4883 	type_T	    *actual;
4884 	where_T	    where = WHERE_INIT;
4885 
4886 	generate_ppconst(cctx, ppconst);
4887 	actual = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4888 	if (check_type(want_type, actual, FALSE, where) == FAIL)
4889 	{
4890 	    if (need_type(actual, want_type, -1, 0, cctx, FALSE, FALSE) == FAIL)
4891 		return FAIL;
4892 	}
4893     }
4894 
4895     return OK;
4896 }
4897 
4898 /*
4899  *	*	number multiplication
4900  *	/	number division
4901  *	%	number modulo
4902  */
4903     static int
4904 compile_expr6(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4905 {
4906     char_u	*op;
4907     char_u	*next;
4908     int		ppconst_used = ppconst->pp_used;
4909 
4910     // get the first expression
4911     if (compile_expr7t(arg, cctx, ppconst) == FAIL)
4912 	return FAIL;
4913 
4914     /*
4915      * Repeat computing, until no "*", "/" or "%" is following.
4916      */
4917     for (;;)
4918     {
4919 	op = may_peek_next_line(cctx, *arg, &next);
4920 	if (*op != '*' && *op != '/' && *op != '%')
4921 	    break;
4922 	if (next != NULL)
4923 	{
4924 	    *arg = next_line_from_context(cctx, TRUE);
4925 	    op = skipwhite(*arg);
4926 	}
4927 
4928 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(op[1]))
4929 	{
4930 	    error_white_both(op, 1);
4931 	    return FAIL;
4932 	}
4933 	if (may_get_next_line_error(op + 1, arg, cctx) == FAIL)
4934 	    return FAIL;
4935 
4936 	// get the second expression
4937 	if (compile_expr7t(arg, cctx, ppconst) == FAIL)
4938 	    return FAIL;
4939 
4940 	if (ppconst->pp_used == ppconst_used + 2
4941 		&& ppconst->pp_tv[ppconst_used].v_type == VAR_NUMBER
4942 		&& ppconst->pp_tv[ppconst_used + 1].v_type == VAR_NUMBER)
4943 	{
4944 	    typval_T	    *tv1 = &ppconst->pp_tv[ppconst_used];
4945 	    typval_T	    *tv2 = &ppconst->pp_tv[ppconst_used + 1];
4946 	    varnumber_T	    res = 0;
4947 	    int		    failed = FALSE;
4948 
4949 	    // both are numbers: compute the result
4950 	    switch (*op)
4951 	    {
4952 		case '*': res = tv1->vval.v_number * tv2->vval.v_number;
4953 			  break;
4954 		case '/': res = num_divide(tv1->vval.v_number,
4955 						  tv2->vval.v_number, &failed);
4956 			  break;
4957 		case '%': res = num_modulus(tv1->vval.v_number,
4958 						  tv2->vval.v_number, &failed);
4959 			  break;
4960 	    }
4961 	    if (failed)
4962 		return FAIL;
4963 	    tv1->vval.v_number = res;
4964 	    --ppconst->pp_used;
4965 	}
4966 	else
4967 	{
4968 	    generate_ppconst(cctx, ppconst);
4969 	    generate_two_op(cctx, op);
4970 	}
4971     }
4972 
4973     return OK;
4974 }
4975 
4976 /*
4977  *      +	number addition or list/blobl concatenation
4978  *      -	number subtraction
4979  *      ..	string concatenation
4980  */
4981     static int
4982 compile_expr5(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4983 {
4984     char_u	*op;
4985     char_u	*next;
4986     int		oplen;
4987     int		ppconst_used = ppconst->pp_used;
4988 
4989     // get the first variable
4990     if (compile_expr6(arg, cctx, ppconst) == FAIL)
4991 	return FAIL;
4992 
4993     /*
4994      * Repeat computing, until no "+", "-" or ".." is following.
4995      */
4996     for (;;)
4997     {
4998 	op = may_peek_next_line(cctx, *arg, &next);
4999 	if (*op != '+' && *op != '-' && !(*op == '.' && *(op + 1) == '.'))
5000 	    break;
5001 	if (op[0] == op[1] && *op != '.' && next)
5002 	    // Finding "++" or "--" on the next line is a separate command.
5003 	    // But ".." is concatenation.
5004 	    break;
5005 	oplen = (*op == '.' ? 2 : 1);
5006 	if (next != NULL)
5007 	{
5008 	    *arg = next_line_from_context(cctx, TRUE);
5009 	    op = skipwhite(*arg);
5010 	}
5011 
5012 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(op[oplen]))
5013 	{
5014 	    error_white_both(op, oplen);
5015 	    return FAIL;
5016 	}
5017 
5018 	if (may_get_next_line_error(op + oplen, arg, cctx) == FAIL)
5019 	    return FAIL;
5020 
5021 	// get the second expression
5022 	if (compile_expr6(arg, cctx, ppconst) == FAIL)
5023 	    return FAIL;
5024 
5025 	if (ppconst->pp_used == ppconst_used + 2
5026 		&& (*op == '.'
5027 		    ? (ppconst->pp_tv[ppconst_used].v_type == VAR_STRING
5028 		    && ppconst->pp_tv[ppconst_used + 1].v_type == VAR_STRING)
5029 		    : (ppconst->pp_tv[ppconst_used].v_type == VAR_NUMBER
5030 		    && ppconst->pp_tv[ppconst_used + 1].v_type == VAR_NUMBER)))
5031 	{
5032 	    typval_T *tv1 = &ppconst->pp_tv[ppconst_used];
5033 	    typval_T *tv2 = &ppconst->pp_tv[ppconst_used + 1];
5034 
5035 	    // concat/subtract/add constant numbers
5036 	    if (*op == '+')
5037 		tv1->vval.v_number = tv1->vval.v_number + tv2->vval.v_number;
5038 	    else if (*op == '-')
5039 		tv1->vval.v_number = tv1->vval.v_number - tv2->vval.v_number;
5040 	    else
5041 	    {
5042 		// concatenate constant strings
5043 		char_u *s1 = tv1->vval.v_string;
5044 		char_u *s2 = tv2->vval.v_string;
5045 		size_t len1 = STRLEN(s1);
5046 
5047 		tv1->vval.v_string = alloc((int)(len1 + STRLEN(s2) + 1));
5048 		if (tv1->vval.v_string == NULL)
5049 		{
5050 		    clear_ppconst(ppconst);
5051 		    return FAIL;
5052 		}
5053 		mch_memmove(tv1->vval.v_string, s1, len1);
5054 		STRCPY(tv1->vval.v_string + len1, s2);
5055 		vim_free(s1);
5056 		vim_free(s2);
5057 	    }
5058 	    --ppconst->pp_used;
5059 	}
5060 	else
5061 	{
5062 	    generate_ppconst(cctx, ppconst);
5063 	    ppconst->pp_is_const = FALSE;
5064 	    if (*op == '.')
5065 	    {
5066 		if (may_generate_2STRING(-2, FALSE, cctx) == FAIL
5067 			|| may_generate_2STRING(-1, FALSE, cctx) == FAIL)
5068 		    return FAIL;
5069 		generate_instr_drop(cctx, ISN_CONCAT, 1);
5070 	    }
5071 	    else
5072 		generate_two_op(cctx, op);
5073 	}
5074     }
5075 
5076     return OK;
5077 }
5078 
5079 /*
5080  * expr5a == expr5b
5081  * expr5a =~ expr5b
5082  * expr5a != expr5b
5083  * expr5a !~ expr5b
5084  * expr5a > expr5b
5085  * expr5a >= expr5b
5086  * expr5a < expr5b
5087  * expr5a <= expr5b
5088  * expr5a is expr5b
5089  * expr5a isnot expr5b
5090  *
5091  * Produces instructions:
5092  *	EVAL expr5a		Push result of "expr5a"
5093  *	EVAL expr5b		Push result of "expr5b"
5094  *	COMPARE			one of the compare instructions
5095  */
5096     static int
5097 compile_expr4(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
5098 {
5099     exprtype_T	type = EXPR_UNKNOWN;
5100     char_u	*p;
5101     char_u	*next;
5102     int		len = 2;
5103     int		type_is = FALSE;
5104     int		ppconst_used = ppconst->pp_used;
5105 
5106     // get the first variable
5107     if (compile_expr5(arg, cctx, ppconst) == FAIL)
5108 	return FAIL;
5109 
5110     p = may_peek_next_line(cctx, *arg, &next);
5111     type = get_compare_type(p, &len, &type_is);
5112 
5113     /*
5114      * If there is a comparative operator, use it.
5115      */
5116     if (type != EXPR_UNKNOWN)
5117     {
5118 	int ic = FALSE;  // Default: do not ignore case
5119 
5120 	if (next != NULL)
5121 	{
5122 	    *arg = next_line_from_context(cctx, TRUE);
5123 	    p = skipwhite(*arg);
5124 	}
5125 	if (type_is && (p[len] == '?' || p[len] == '#'))
5126 	{
5127 	    semsg(_(e_invalid_expression_str), *arg);
5128 	    return FAIL;
5129 	}
5130 	// extra question mark appended: ignore case
5131 	if (p[len] == '?')
5132 	{
5133 	    ic = TRUE;
5134 	    ++len;
5135 	}
5136 	// extra '#' appended: match case (ignored)
5137 	else if (p[len] == '#')
5138 	    ++len;
5139 	// nothing appended: match case
5140 
5141 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[len]))
5142 	{
5143 	    error_white_both(p, len);
5144 	    return FAIL;
5145 	}
5146 
5147 	// get the second variable
5148 	if (may_get_next_line_error(p + len, arg, cctx) == FAIL)
5149 	    return FAIL;
5150 
5151 	if (compile_expr5(arg, cctx, ppconst) == FAIL)
5152 	    return FAIL;
5153 
5154 	if (ppconst->pp_used == ppconst_used + 2)
5155 	{
5156 	    typval_T *	tv1 = &ppconst->pp_tv[ppconst->pp_used - 2];
5157 	    typval_T	*tv2 = &ppconst->pp_tv[ppconst->pp_used - 1];
5158 	    int		ret;
5159 
5160 	    // Both sides are a constant, compute the result now.
5161 	    // First check for a valid combination of types, this is more
5162 	    // strict than typval_compare().
5163 	    if (check_compare_types(type, tv1, tv2) == FAIL)
5164 		ret = FAIL;
5165 	    else
5166 	    {
5167 		ret = typval_compare(tv1, tv2, type, ic);
5168 		tv1->v_type = VAR_BOOL;
5169 		tv1->vval.v_number = tv1->vval.v_number
5170 						      ? VVAL_TRUE : VVAL_FALSE;
5171 		clear_tv(tv2);
5172 		--ppconst->pp_used;
5173 	    }
5174 	    return ret;
5175 	}
5176 
5177 	generate_ppconst(cctx, ppconst);
5178 	return generate_COMPARE(cctx, type, ic);
5179     }
5180 
5181     return OK;
5182 }
5183 
5184 static int compile_expr3(char_u **arg,  cctx_T *cctx, ppconst_T *ppconst);
5185 
5186 /*
5187  * Compile || or &&.
5188  */
5189     static int
5190 compile_and_or(
5191 	char_u **arg,
5192 	cctx_T	*cctx,
5193 	char	*op,
5194 	ppconst_T *ppconst,
5195 	int	ppconst_used UNUSED)
5196 {
5197     char_u	*next;
5198     char_u	*p = may_peek_next_line(cctx, *arg, &next);
5199     int		opchar = *op;
5200 
5201     if (p[0] == opchar && p[1] == opchar)
5202     {
5203 	garray_T	*instr = &cctx->ctx_instr;
5204 	garray_T	end_ga;
5205 
5206 	/*
5207 	 * Repeat until there is no following "||" or "&&"
5208 	 */
5209 	ga_init2(&end_ga, sizeof(int), 10);
5210 	while (p[0] == opchar && p[1] == opchar)
5211 	{
5212 	    long	start_lnum = SOURCING_LNUM;
5213 	    long	save_sourcing_lnum;
5214 	    int		start_ctx_lnum = cctx->ctx_lnum;
5215 	    int		save_lnum;
5216 	    int		status;
5217 
5218 	    if (next != NULL)
5219 	    {
5220 		*arg = next_line_from_context(cctx, TRUE);
5221 		p = skipwhite(*arg);
5222 	    }
5223 
5224 	    if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[2]))
5225 	    {
5226 		semsg(_(e_white_space_required_before_and_after_str_at_str),
5227 									op, p);
5228 		return FAIL;
5229 	    }
5230 
5231 	    save_sourcing_lnum = SOURCING_LNUM;
5232 	    SOURCING_LNUM = start_lnum;
5233 	    save_lnum = cctx->ctx_lnum;
5234 	    cctx->ctx_lnum = start_ctx_lnum;
5235 
5236 	    status = check_ppconst_bool(ppconst);
5237 	    if (status != FAIL)
5238 	    {
5239 		// TODO: use ppconst if the value is a constant
5240 		generate_ppconst(cctx, ppconst);
5241 
5242 		// Every part must evaluate to a bool.
5243 		status = bool_on_stack(cctx);
5244 		if (status != FAIL)
5245 		    status = ga_grow(&end_ga, 1);
5246 	    }
5247 	    cctx->ctx_lnum = save_lnum;
5248 	    if (status == FAIL)
5249 	    {
5250 		ga_clear(&end_ga);
5251 		return FAIL;
5252 	    }
5253 
5254 	    *(((int *)end_ga.ga_data) + end_ga.ga_len) = instr->ga_len;
5255 	    ++end_ga.ga_len;
5256 	    generate_JUMP(cctx, opchar == '|'
5257 				 ?  JUMP_IF_COND_TRUE : JUMP_IF_COND_FALSE, 0);
5258 
5259 	    // eval the next expression
5260 	    SOURCING_LNUM = save_sourcing_lnum;
5261 	    if (may_get_next_line_error(p + 2, arg, cctx) == FAIL)
5262 	    {
5263 		ga_clear(&end_ga);
5264 		return FAIL;
5265 	    }
5266 
5267 	    if ((opchar == '|' ? compile_expr3(arg, cctx, ppconst)
5268 				  : compile_expr4(arg, cctx, ppconst)) == FAIL)
5269 	    {
5270 		ga_clear(&end_ga);
5271 		return FAIL;
5272 	    }
5273 
5274 	    p = may_peek_next_line(cctx, *arg, &next);
5275 	}
5276 
5277 	if (check_ppconst_bool(ppconst) == FAIL)
5278 	{
5279 	    ga_clear(&end_ga);
5280 	    return FAIL;
5281 	}
5282 	generate_ppconst(cctx, ppconst);
5283 
5284 	// Every part must evaluate to a bool.
5285 	if (bool_on_stack(cctx) == FAIL)
5286 	{
5287 	    ga_clear(&end_ga);
5288 	    return FAIL;
5289 	}
5290 
5291 	// Fill in the end label in all jumps.
5292 	while (end_ga.ga_len > 0)
5293 	{
5294 	    isn_T	*isn;
5295 
5296 	    --end_ga.ga_len;
5297 	    isn = ((isn_T *)instr->ga_data)
5298 				  + *(((int *)end_ga.ga_data) + end_ga.ga_len);
5299 	    isn->isn_arg.jump.jump_where = instr->ga_len;
5300 	}
5301 	ga_clear(&end_ga);
5302     }
5303 
5304     return OK;
5305 }
5306 
5307 /*
5308  * expr4a && expr4a && expr4a	    logical AND
5309  *
5310  * Produces instructions:
5311  *	EVAL expr4a		Push result of "expr4a"
5312  *	COND2BOOL		convert to bool if needed
5313  *	JUMP_IF_COND_FALSE end
5314  *	EVAL expr4b		Push result of "expr4b"
5315  *	JUMP_IF_COND_FALSE end
5316  *	EVAL expr4c		Push result of "expr4c"
5317  * end:
5318  */
5319     static int
5320 compile_expr3(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
5321 {
5322     int		ppconst_used = ppconst->pp_used;
5323 
5324     // get the first variable
5325     if (compile_expr4(arg, cctx, ppconst) == FAIL)
5326 	return FAIL;
5327 
5328     // || and && work almost the same
5329     return compile_and_or(arg, cctx, "&&", ppconst, ppconst_used);
5330 }
5331 
5332 /*
5333  * expr3a || expr3b || expr3c	    logical OR
5334  *
5335  * Produces instructions:
5336  *	EVAL expr3a		Push result of "expr3a"
5337  *	COND2BOOL		convert to bool if needed
5338  *	JUMP_IF_COND_TRUE end
5339  *	EVAL expr3b		Push result of "expr3b"
5340  *	JUMP_IF_COND_TRUE end
5341  *	EVAL expr3c		Push result of "expr3c"
5342  * end:
5343  */
5344     static int
5345 compile_expr2(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
5346 {
5347     int		ppconst_used = ppconst->pp_used;
5348 
5349     // eval the first expression
5350     if (compile_expr3(arg, cctx, ppconst) == FAIL)
5351 	return FAIL;
5352 
5353     // || and && work almost the same
5354     return compile_and_or(arg, cctx, "||", ppconst, ppconst_used);
5355 }
5356 
5357 /*
5358  * Toplevel expression: expr2 ? expr1a : expr1b
5359  * Produces instructions:
5360  *	EVAL expr2		Push result of "expr2"
5361  *      JUMP_IF_FALSE alt	jump if false
5362  *      EVAL expr1a
5363  *      JUMP_ALWAYS end
5364  * alt:	EVAL expr1b
5365  * end:
5366  *
5367  * Toplevel expression: expr2 ?? expr1
5368  * Produces instructions:
5369  *	EVAL expr2		    Push result of "expr2"
5370  *      JUMP_AND_KEEP_IF_TRUE end   jump if true
5371  *      EVAL expr1
5372  * end:
5373  */
5374     static int
5375 compile_expr1(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
5376 {
5377     char_u	*p;
5378     int		ppconst_used = ppconst->pp_used;
5379     char_u	*next;
5380 
5381     // Ignore all kinds of errors when not producing code.
5382     if (cctx->ctx_skip == SKIP_YES)
5383     {
5384 	skip_expr_cctx(arg, cctx);
5385 	return OK;
5386     }
5387 
5388     // Evaluate the first expression.
5389     if (compile_expr2(arg, cctx, ppconst) == FAIL)
5390 	return FAIL;
5391 
5392     p = may_peek_next_line(cctx, *arg, &next);
5393     if (*p == '?')
5394     {
5395 	int		op_falsy = p[1] == '?';
5396 	garray_T	*instr = &cctx->ctx_instr;
5397 	garray_T	*stack = &cctx->ctx_type_stack;
5398 	int		alt_idx = instr->ga_len;
5399 	int		end_idx = 0;
5400 	isn_T		*isn;
5401 	type_T		*type1 = NULL;
5402 	int		has_const_expr = FALSE;
5403 	int		const_value = FALSE;
5404 	int		save_skip = cctx->ctx_skip;
5405 
5406 	if (next != NULL)
5407 	{
5408 	    *arg = next_line_from_context(cctx, TRUE);
5409 	    p = skipwhite(*arg);
5410 	}
5411 
5412 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[1 + op_falsy]))
5413 	{
5414 	    semsg(_(e_white_space_required_before_and_after_str_at_str),
5415 						     op_falsy ? "??" : "?", p);
5416 	    return FAIL;
5417 	}
5418 
5419 	if (ppconst->pp_used == ppconst_used + 1)
5420 	{
5421 	    // the condition is a constant, we know whether the ? or the :
5422 	    // expression is to be evaluated.
5423 	    has_const_expr = TRUE;
5424 	    if (op_falsy)
5425 		const_value = tv2bool(&ppconst->pp_tv[ppconst_used]);
5426 	    else
5427 	    {
5428 		int error = FALSE;
5429 
5430 		const_value = tv_get_bool_chk(&ppconst->pp_tv[ppconst_used],
5431 								       &error);
5432 		if (error)
5433 		    return FAIL;
5434 	    }
5435 	    cctx->ctx_skip = save_skip == SKIP_YES ||
5436 		 (op_falsy ? const_value : !const_value) ? SKIP_YES : SKIP_NOT;
5437 
5438 	    if (op_falsy && cctx->ctx_skip == SKIP_YES)
5439 		// "left ?? right" and "left" is truthy: produce "left"
5440 		generate_ppconst(cctx, ppconst);
5441 	    else
5442 	    {
5443 		clear_tv(&ppconst->pp_tv[ppconst_used]);
5444 		--ppconst->pp_used;
5445 	    }
5446 	}
5447 	else
5448 	{
5449 	    generate_ppconst(cctx, ppconst);
5450 	    if (op_falsy)
5451 		end_idx = instr->ga_len;
5452 	    generate_JUMP(cctx, op_falsy
5453 				   ? JUMP_AND_KEEP_IF_TRUE : JUMP_IF_FALSE, 0);
5454 	    if (op_falsy)
5455 		type1 = ((type_T **)stack->ga_data)[stack->ga_len];
5456 	}
5457 
5458 	// evaluate the second expression; any type is accepted
5459 	if (may_get_next_line_error(p + 1 + op_falsy, arg, cctx) == FAIL)
5460 	    return FAIL;
5461 	if (compile_expr1(arg, cctx, ppconst) == FAIL)
5462 	    return FAIL;
5463 
5464 	if (!has_const_expr)
5465 	{
5466 	    generate_ppconst(cctx, ppconst);
5467 
5468 	    if (!op_falsy)
5469 	    {
5470 		// remember the type and drop it
5471 		--stack->ga_len;
5472 		type1 = ((type_T **)stack->ga_data)[stack->ga_len];
5473 
5474 		end_idx = instr->ga_len;
5475 		generate_JUMP(cctx, JUMP_ALWAYS, 0);
5476 
5477 		// jump here from JUMP_IF_FALSE
5478 		isn = ((isn_T *)instr->ga_data) + alt_idx;
5479 		isn->isn_arg.jump.jump_where = instr->ga_len;
5480 	    }
5481 	}
5482 
5483 	if (!op_falsy)
5484 	{
5485 	    // Check for the ":".
5486 	    p = may_peek_next_line(cctx, *arg, &next);
5487 	    if (*p != ':')
5488 	    {
5489 		emsg(_(e_missing_colon));
5490 		return FAIL;
5491 	    }
5492 	    if (next != NULL)
5493 	    {
5494 		*arg = next_line_from_context(cctx, TRUE);
5495 		p = skipwhite(*arg);
5496 	    }
5497 
5498 	    if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[1]))
5499 	    {
5500 		semsg(_(e_white_space_required_before_and_after_str_at_str),
5501 								       ":", p);
5502 		return FAIL;
5503 	    }
5504 
5505 	    // evaluate the third expression
5506 	    if (has_const_expr)
5507 		cctx->ctx_skip = save_skip == SKIP_YES || const_value
5508 							 ? SKIP_YES : SKIP_NOT;
5509 	    if (may_get_next_line_error(p + 1, arg, cctx) == FAIL)
5510 		return FAIL;
5511 	    if (compile_expr1(arg, cctx, ppconst) == FAIL)
5512 		return FAIL;
5513 	}
5514 
5515 	if (!has_const_expr)
5516 	{
5517 	    type_T	**typep;
5518 
5519 	    generate_ppconst(cctx, ppconst);
5520 
5521 	    // If the types differ, the result has a more generic type.
5522 	    typep = ((type_T **)stack->ga_data) + stack->ga_len - 1;
5523 	    common_type(type1, *typep, typep, cctx->ctx_type_list);
5524 
5525 	    // jump here from JUMP_ALWAYS or JUMP_AND_KEEP_IF_TRUE
5526 	    isn = ((isn_T *)instr->ga_data) + end_idx;
5527 	    isn->isn_arg.jump.jump_where = instr->ga_len;
5528 	}
5529 
5530 	cctx->ctx_skip = save_skip;
5531     }
5532     return OK;
5533 }
5534 
5535 /*
5536  * Toplevel expression.
5537  * Sets "is_const" (if not NULL) to indicate the value is a constant.
5538  * Returns OK or FAIL.
5539  */
5540     static int
5541 compile_expr0_ext(char_u **arg,  cctx_T *cctx, int *is_const)
5542 {
5543     ppconst_T	ppconst;
5544 
5545     CLEAR_FIELD(ppconst);
5546     if (compile_expr1(arg, cctx, &ppconst) == FAIL)
5547     {
5548 	clear_ppconst(&ppconst);
5549 	return FAIL;
5550     }
5551     if (is_const != NULL)
5552 	*is_const = ppconst.pp_used > 0 || ppconst.pp_is_const;
5553     if (generate_ppconst(cctx, &ppconst) == FAIL)
5554 	return FAIL;
5555     return OK;
5556 }
5557 
5558 /*
5559  * Toplevel expression.
5560  */
5561     static int
5562 compile_expr0(char_u **arg,  cctx_T *cctx)
5563 {
5564     return compile_expr0_ext(arg, cctx, NULL);
5565 }
5566 
5567 /*
5568  * Compile "return [expr]".
5569  * When "legacy" is TRUE evaluate [expr] with legacy syntax
5570  */
5571     static char_u *
5572 compile_return(char_u *arg, int check_return_type, int legacy, cctx_T *cctx)
5573 {
5574     char_u	*p = arg;
5575     garray_T	*stack = &cctx->ctx_type_stack;
5576     type_T	*stack_type;
5577 
5578     if (*p != NUL && *p != '|' && *p != '\n')
5579     {
5580 	if (legacy)
5581 	{
5582 	    int save_flags = cmdmod.cmod_flags;
5583 
5584 	    generate_LEGACY_EVAL(cctx, p);
5585 	    if (need_type(&t_any, cctx->ctx_ufunc->uf_ret_type, -1,
5586 						0, cctx, FALSE, FALSE) == FAIL)
5587 		return NULL;
5588 	    cmdmod.cmod_flags |= CMOD_LEGACY;
5589 	    (void)skip_expr(&p, NULL);
5590 	    cmdmod.cmod_flags = save_flags;
5591 	}
5592 	else
5593 	{
5594 	    // compile return argument into instructions
5595 	    if (compile_expr0(&p, cctx) == FAIL)
5596 		return NULL;
5597 	}
5598 
5599 	if (cctx->ctx_skip != SKIP_YES)
5600 	{
5601 	    // "check_return_type" with uf_ret_type set to &t_unknown is used
5602 	    // for an inline function without a specified return type.  Set the
5603 	    // return type here.
5604 	    stack_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
5605 	    if ((check_return_type && (cctx->ctx_ufunc->uf_ret_type == NULL
5606 				|| cctx->ctx_ufunc->uf_ret_type == &t_unknown
5607 				|| cctx->ctx_ufunc->uf_ret_type == &t_any))
5608 		    || (!check_return_type
5609 				&& cctx->ctx_ufunc->uf_ret_type == &t_unknown))
5610 	    {
5611 		cctx->ctx_ufunc->uf_ret_type = stack_type;
5612 	    }
5613 	    else
5614 	    {
5615 		if (cctx->ctx_ufunc->uf_ret_type->tt_type == VAR_VOID
5616 			&& stack_type->tt_type != VAR_VOID
5617 			&& stack_type->tt_type != VAR_UNKNOWN)
5618 		{
5619 		    emsg(_(e_returning_value_in_function_without_return_type));
5620 		    return NULL;
5621 		}
5622 		if (need_type(stack_type, cctx->ctx_ufunc->uf_ret_type, -1,
5623 						0, cctx, FALSE, FALSE) == FAIL)
5624 		    return NULL;
5625 	    }
5626 	}
5627     }
5628     else
5629     {
5630 	// "check_return_type" cannot be TRUE, only used for a lambda which
5631 	// always has an argument.
5632 	if (cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_VOID
5633 		&& cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_UNKNOWN)
5634 	{
5635 	    emsg(_(e_missing_return_value));
5636 	    return NULL;
5637 	}
5638 
5639 	// No argument, return zero.
5640 	generate_PUSHNR(cctx, 0);
5641     }
5642 
5643     // Undo any command modifiers.
5644     generate_undo_cmdmods(cctx);
5645 
5646     if (cctx->ctx_skip != SKIP_YES && generate_instr(cctx, ISN_RETURN) == NULL)
5647 	return NULL;
5648 
5649     // "return val | endif" is possible
5650     return skipwhite(p);
5651 }
5652 
5653 /*
5654  * Get a line from the compilation context, compatible with exarg_T getline().
5655  * Return a pointer to the line in allocated memory.
5656  * Return NULL for end-of-file or some error.
5657  */
5658     static char_u *
5659 exarg_getline(
5660 	int c UNUSED,
5661 	void *cookie,
5662 	int indent UNUSED,
5663 	getline_opt_T options UNUSED)
5664 {
5665     cctx_T  *cctx = (cctx_T *)cookie;
5666     char_u  *p;
5667 
5668     for (;;)
5669     {
5670 	if (cctx->ctx_lnum >= cctx->ctx_ufunc->uf_lines.ga_len - 1)
5671 	    return NULL;
5672 	++cctx->ctx_lnum;
5673 	p = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum];
5674 	// Comment lines result in NULL pointers, skip them.
5675 	if (p != NULL)
5676 	    return vim_strsave(p);
5677     }
5678 }
5679 
5680     void
5681 fill_exarg_from_cctx(exarg_T *eap, cctx_T *cctx)
5682 {
5683     eap->getline = exarg_getline;
5684     eap->cookie = cctx;
5685 }
5686 
5687 /*
5688  * Compile a nested :def command.
5689  */
5690     static char_u *
5691 compile_nested_function(exarg_T *eap, cctx_T *cctx)
5692 {
5693     int		is_global = *eap->arg == 'g' && eap->arg[1] == ':';
5694     char_u	*name_start = eap->arg;
5695     char_u	*name_end = to_name_end(eap->arg, TRUE);
5696     char_u	*lambda_name;
5697     ufunc_T	*ufunc;
5698     int		r = FAIL;
5699     compiletype_T   compile_type;
5700 
5701     if (eap->forceit)
5702     {
5703 	emsg(_(e_cannot_use_bang_with_nested_def));
5704 	return NULL;
5705     }
5706 
5707     if (*name_start == '/')
5708     {
5709 	name_end = skip_regexp(name_start + 1, '/', TRUE);
5710 	if (*name_end == '/')
5711 	    ++name_end;
5712 	set_nextcmd(eap, name_end);
5713     }
5714     if (name_end == name_start || *skipwhite(name_end) != '(')
5715     {
5716 	if (!ends_excmd2(name_start, name_end))
5717 	{
5718 	    semsg(_(e_invalid_command_str), eap->cmd);
5719 	    return NULL;
5720 	}
5721 
5722 	// "def" or "def Name": list functions
5723 	if (generate_DEF(cctx, name_start, name_end - name_start) == FAIL)
5724 	    return NULL;
5725 	return eap->nextcmd == NULL ? (char_u *)"" : eap->nextcmd;
5726     }
5727 
5728     // Only g:Func() can use a namespace.
5729     if (name_start[1] == ':' && !is_global)
5730     {
5731 	semsg(_(e_namespace_not_supported_str), name_start);
5732 	return NULL;
5733     }
5734     if (check_defined(name_start, name_end - name_start, cctx, FALSE) == FAIL)
5735 	return NULL;
5736 
5737     eap->arg = name_end;
5738     fill_exarg_from_cctx(eap, cctx);
5739 
5740     eap->forceit = FALSE;
5741     lambda_name = vim_strsave(get_lambda_name());
5742     if (lambda_name == NULL)
5743 	return NULL;
5744     ufunc = define_function(eap, lambda_name);
5745 
5746     if (ufunc == NULL)
5747     {
5748 	r = eap->skip ? OK : FAIL;
5749 	goto theend;
5750     }
5751 
5752     // copy over the block scope IDs before compiling
5753     if (!is_global && cctx->ctx_ufunc->uf_block_depth > 0)
5754     {
5755 	int block_depth = cctx->ctx_ufunc->uf_block_depth;
5756 
5757 	ufunc->uf_block_ids = ALLOC_MULT(int, block_depth);
5758 	if (ufunc->uf_block_ids != NULL)
5759 	{
5760 	    mch_memmove(ufunc->uf_block_ids, cctx->ctx_ufunc->uf_block_ids,
5761 						    sizeof(int) * block_depth);
5762 	    ufunc->uf_block_depth = block_depth;
5763 	}
5764     }
5765 
5766     compile_type = COMPILE_TYPE(ufunc);
5767 #ifdef FEAT_PROFILE
5768     // If the outer function is profiled, also compile the nested function for
5769     // profiling.
5770     if (cctx->ctx_compile_type == CT_PROFILE)
5771 	compile_type = CT_PROFILE;
5772 #endif
5773     if (func_needs_compiling(ufunc, compile_type)
5774 	    && compile_def_function(ufunc, TRUE, compile_type, cctx) == FAIL)
5775     {
5776 	func_ptr_unref(ufunc);
5777 	goto theend;
5778     }
5779 
5780 #ifdef FEAT_PROFILE
5781     // When the outer function is compiled for profiling, the nested function
5782     // may be called without profiling.  Compile it here in the right context.
5783     if (compile_type == CT_PROFILE && func_needs_compiling(ufunc, CT_NONE))
5784 	compile_def_function(ufunc, FALSE, CT_NONE, cctx);
5785 #endif
5786 
5787     if (is_global)
5788     {
5789 	char_u *func_name = vim_strnsave(name_start + 2,
5790 						    name_end - name_start - 2);
5791 
5792 	if (func_name == NULL)
5793 	    r = FAIL;
5794 	else
5795 	{
5796 	    r = generate_NEWFUNC(cctx, lambda_name, func_name);
5797 	    lambda_name = NULL;
5798 	}
5799     }
5800     else
5801     {
5802 	// Define a local variable for the function reference.
5803 	lvar_T	*lvar = reserve_local(cctx, name_start, name_end - name_start,
5804 						    TRUE, ufunc->uf_func_type);
5805 
5806 	if (lvar == NULL)
5807 	    goto theend;
5808 	if (generate_FUNCREF(cctx, ufunc) == FAIL)
5809 	    goto theend;
5810 	r = generate_STORE(cctx, ISN_STORE, lvar->lv_idx, NULL);
5811     }
5812     // TODO: warning for trailing text?
5813 
5814 theend:
5815     vim_free(lambda_name);
5816     return r == FAIL ? NULL : (char_u *)"";
5817 }
5818 
5819 /*
5820  * Return the length of an assignment operator, or zero if there isn't one.
5821  */
5822     int
5823 assignment_len(char_u *p, int *heredoc)
5824 {
5825     if (*p == '=')
5826     {
5827 	if (p[1] == '<' && p[2] == '<')
5828 	{
5829 	    *heredoc = TRUE;
5830 	    return 3;
5831 	}
5832 	return 1;
5833     }
5834     if (vim_strchr((char_u *)"+-*/%", *p) != NULL && p[1] == '=')
5835 	return 2;
5836     if (STRNCMP(p, "..=", 3) == 0)
5837 	return 3;
5838     return 0;
5839 }
5840 
5841 /*
5842  * Generate the load instruction for "name".
5843  */
5844     static void
5845 generate_loadvar(
5846 	cctx_T		*cctx,
5847 	assign_dest_T	dest,
5848 	char_u		*name,
5849 	lvar_T		*lvar,
5850 	type_T		*type)
5851 {
5852     switch (dest)
5853     {
5854 	case dest_option:
5855 	    // TODO: check the option exists
5856 	    generate_LOAD(cctx, ISN_LOADOPT, 0, name, type);
5857 	    break;
5858 	case dest_global:
5859 	    if (vim_strchr(name, AUTOLOAD_CHAR) == NULL)
5860 		generate_LOAD(cctx, ISN_LOADG, 0, name + 2, type);
5861 	    else
5862 		generate_LOAD(cctx, ISN_LOADAUTO, 0, name, type);
5863 	    break;
5864 	case dest_buffer:
5865 	    generate_LOAD(cctx, ISN_LOADB, 0, name + 2, type);
5866 	    break;
5867 	case dest_window:
5868 	    generate_LOAD(cctx, ISN_LOADW, 0, name + 2, type);
5869 	    break;
5870 	case dest_tab:
5871 	    generate_LOAD(cctx, ISN_LOADT, 0, name + 2, type);
5872 	    break;
5873 	case dest_script:
5874 	    compile_load_scriptvar(cctx,
5875 		    name + (name[1] == ':' ? 2 : 0), NULL, NULL, TRUE);
5876 	    break;
5877 	case dest_env:
5878 	    // Include $ in the name here
5879 	    generate_LOAD(cctx, ISN_LOADENV, 0, name, type);
5880 	    break;
5881 	case dest_reg:
5882 	    generate_LOAD(cctx, ISN_LOADREG, name[1], NULL, &t_string);
5883 	    break;
5884 	case dest_vimvar:
5885 	    generate_LOADV(cctx, name + 2, TRUE);
5886 	    break;
5887 	case dest_local:
5888 	    if (lvar->lv_from_outer > 0)
5889 		generate_LOADOUTER(cctx, lvar->lv_idx, lvar->lv_from_outer,
5890 									 type);
5891 	    else
5892 		generate_LOAD(cctx, ISN_LOAD, lvar->lv_idx, NULL, type);
5893 	    break;
5894 	case dest_expr:
5895 	    // list or dict value should already be on the stack.
5896 	    break;
5897     }
5898 }
5899 
5900 /*
5901  * Skip over "[expr]" or ".member".
5902  * Does not check for any errors.
5903  */
5904     static char_u *
5905 skip_index(char_u *start)
5906 {
5907     char_u *p = start;
5908 
5909     if (*p == '[')
5910     {
5911 	p = skipwhite(p + 1);
5912 	(void)skip_expr(&p, NULL);
5913 	p = skipwhite(p);
5914 	if (*p == ']')
5915 	    return p + 1;
5916 	return p;
5917     }
5918     // if (*p == '.')
5919     return to_name_end(p + 1, TRUE);
5920 }
5921 
5922     void
5923 vim9_declare_error(char_u *name)
5924 {
5925     char *scope = "";
5926 
5927     switch (*name)
5928     {
5929 	case 'g': scope = _("global"); break;
5930 	case 'b': scope = _("buffer"); break;
5931 	case 'w': scope = _("window"); break;
5932 	case 't': scope = _("tab"); break;
5933 	case 'v': scope = "v:"; break;
5934 	case '$': semsg(_(e_cannot_declare_an_environment_variable), name);
5935 		  return;
5936 	case '&': semsg(_(e_cannot_declare_an_option), name);
5937 		  return;
5938 	case '@': semsg(_(e_cannot_declare_a_register_str), name);
5939 		  return;
5940 	default: return;
5941     }
5942     semsg(_(e_cannot_declare_a_scope_variable), scope, name);
5943 }
5944 
5945 /*
5946  * For one assignment figure out the type of destination.  Return it in "dest".
5947  * When not recognized "dest" is not set.
5948  * For an option "opt_flags" is set.
5949  * For a v:var "vimvaridx" is set.
5950  * "type" is set to the destination type if known, unchanted otherwise.
5951  * Return FAIL if an error message was given.
5952  */
5953     static int
5954 get_var_dest(
5955 	char_u		*name,
5956 	assign_dest_T	*dest,
5957 	int		cmdidx,
5958 	int		*opt_flags,
5959 	int		*vimvaridx,
5960 	type_T		**type,
5961 	cctx_T		*cctx)
5962 {
5963     char_u *p;
5964 
5965     if (*name == '&')
5966     {
5967 	int		cc;
5968 	long		numval;
5969 	getoption_T	opt_type;
5970 
5971 	*dest = dest_option;
5972 	if (cmdidx == CMD_final || cmdidx == CMD_const)
5973 	{
5974 	    emsg(_(e_const_option));
5975 	    return FAIL;
5976 	}
5977 	p = name;
5978 	p = find_option_end(&p, opt_flags);
5979 	if (p == NULL)
5980 	{
5981 	    // cannot happen?
5982 	    emsg(_(e_unexpected_characters_in_assignment));
5983 	    return FAIL;
5984 	}
5985 	cc = *p;
5986 	*p = NUL;
5987 	opt_type = get_option_value(skip_option_env_lead(name),
5988 						    &numval, NULL, *opt_flags);
5989 	*p = cc;
5990 	switch (opt_type)
5991 	{
5992 	    case gov_unknown:
5993 		    semsg(_(e_unknown_option), name);
5994 		    return FAIL;
5995 	    case gov_string:
5996 	    case gov_hidden_string:
5997 		    *type = &t_string;
5998 		    break;
5999 	    case gov_bool:
6000 	    case gov_hidden_bool:
6001 		    *type = &t_bool;
6002 		    break;
6003 	    case gov_number:
6004 	    case gov_hidden_number:
6005 		    *type = &t_number;
6006 		    break;
6007 	}
6008     }
6009     else if (*name == '$')
6010     {
6011 	*dest = dest_env;
6012 	*type = &t_string;
6013     }
6014     else if (*name == '@')
6015     {
6016 	if (name[1] != '@'
6017 			&& (!valid_yank_reg(name[1], FALSE) || name[1] == '.'))
6018 	{
6019 	    emsg_invreg(name[1]);
6020 	    return FAIL;
6021 	}
6022 	*dest = dest_reg;
6023 	*type = name[1] == '#' ? &t_number_or_string : &t_string;
6024     }
6025     else if (STRNCMP(name, "g:", 2) == 0)
6026     {
6027 	*dest = dest_global;
6028     }
6029     else if (STRNCMP(name, "b:", 2) == 0)
6030     {
6031 	*dest = dest_buffer;
6032     }
6033     else if (STRNCMP(name, "w:", 2) == 0)
6034     {
6035 	*dest = dest_window;
6036     }
6037     else if (STRNCMP(name, "t:", 2) == 0)
6038     {
6039 	*dest = dest_tab;
6040     }
6041     else if (STRNCMP(name, "v:", 2) == 0)
6042     {
6043 	typval_T	*vtv;
6044 	int		di_flags;
6045 
6046 	*vimvaridx = find_vim_var(name + 2, &di_flags);
6047 	if (*vimvaridx < 0)
6048 	{
6049 	    semsg(_(e_variable_not_found_str), name);
6050 	    return FAIL;
6051 	}
6052 	// We use the current value of "sandbox" here, is that OK?
6053 	if (var_check_ro(di_flags, name, FALSE))
6054 	    return FAIL;
6055 	*dest = dest_vimvar;
6056 	vtv = get_vim_var_tv(*vimvaridx);
6057 	*type = typval2type_vimvar(vtv, cctx->ctx_type_list);
6058     }
6059     return OK;
6060 }
6061 
6062 /*
6063  * Generate a STORE instruction for "dest", not being "dest_local".
6064  * Return FAIL when out of memory.
6065  */
6066     static int
6067 generate_store_var(
6068 	cctx_T		*cctx,
6069 	assign_dest_T	dest,
6070 	int		opt_flags,
6071 	int		vimvaridx,
6072 	int		scriptvar_idx,
6073 	int		scriptvar_sid,
6074 	type_T		*type,
6075 	char_u		*name)
6076 {
6077     switch (dest)
6078     {
6079 	case dest_option:
6080 	    return generate_STOREOPT(cctx, skip_option_env_lead(name),
6081 								    opt_flags);
6082 	case dest_global:
6083 	    // include g: with the name, easier to execute that way
6084 	    return generate_STORE(cctx, vim_strchr(name, AUTOLOAD_CHAR) == NULL
6085 					? ISN_STOREG : ISN_STOREAUTO, 0, name);
6086 	case dest_buffer:
6087 	    // include b: with the name, easier to execute that way
6088 	    return generate_STORE(cctx, ISN_STOREB, 0, name);
6089 	case dest_window:
6090 	    // include w: with the name, easier to execute that way
6091 	    return generate_STORE(cctx, ISN_STOREW, 0, name);
6092 	case dest_tab:
6093 	    // include t: with the name, easier to execute that way
6094 	    return generate_STORE(cctx, ISN_STORET, 0, name);
6095 	case dest_env:
6096 	    return generate_STORE(cctx, ISN_STOREENV, 0, name + 1);
6097 	case dest_reg:
6098 	    return generate_STORE(cctx, ISN_STOREREG,
6099 					 name[1] == '@' ? '"' : name[1], NULL);
6100 	case dest_vimvar:
6101 	    return generate_STORE(cctx, ISN_STOREV, vimvaridx, NULL);
6102 	case dest_script:
6103 	    if (scriptvar_idx < 0)
6104 		// "s:" may be included in the name.
6105 		return generate_OLDSCRIPT(cctx, ISN_STORES, name,
6106 							  scriptvar_sid, type);
6107 	    return generate_VIM9SCRIPT(cctx, ISN_STORESCRIPT,
6108 					   scriptvar_sid, scriptvar_idx, type);
6109 	case dest_local:
6110 	case dest_expr:
6111 	    // cannot happen
6112 	    break;
6113     }
6114     return FAIL;
6115 }
6116 
6117     static int
6118 generate_store_lhs(cctx_T *cctx, lhs_T *lhs, int instr_count)
6119 {
6120     if (lhs->lhs_dest != dest_local)
6121 	return generate_store_var(cctx, lhs->lhs_dest,
6122 			    lhs->lhs_opt_flags, lhs->lhs_vimvaridx,
6123 			    lhs->lhs_scriptvar_idx, lhs->lhs_scriptvar_sid,
6124 			    lhs->lhs_type, lhs->lhs_name);
6125 
6126     if (lhs->lhs_lvar != NULL)
6127     {
6128 	garray_T	*instr = &cctx->ctx_instr;
6129 	isn_T		*isn = ((isn_T *)instr->ga_data) + instr->ga_len - 1;
6130 
6131 	// optimization: turn "var = 123" from ISN_PUSHNR + ISN_STORE into
6132 	// ISN_STORENR
6133 	if (lhs->lhs_lvar->lv_from_outer == 0
6134 		&& instr->ga_len == instr_count + 1
6135 		&& isn->isn_type == ISN_PUSHNR)
6136 	{
6137 	    varnumber_T val = isn->isn_arg.number;
6138 	    garray_T    *stack = &cctx->ctx_type_stack;
6139 
6140 	    isn->isn_type = ISN_STORENR;
6141 	    isn->isn_arg.storenr.stnr_idx = lhs->lhs_lvar->lv_idx;
6142 	    isn->isn_arg.storenr.stnr_val = val;
6143 	    if (stack->ga_len > 0)
6144 		--stack->ga_len;
6145 	}
6146 	else if (lhs->lhs_lvar->lv_from_outer > 0)
6147 	    generate_STOREOUTER(cctx, lhs->lhs_lvar->lv_idx,
6148 						 lhs->lhs_lvar->lv_from_outer);
6149 	else
6150 	    generate_STORE(cctx, ISN_STORE, lhs->lhs_lvar->lv_idx, NULL);
6151     }
6152     return OK;
6153 }
6154 
6155     static int
6156 is_decl_command(int cmdidx)
6157 {
6158     return cmdidx == CMD_let || cmdidx == CMD_var
6159 				 || cmdidx == CMD_final || cmdidx == CMD_const;
6160 }
6161 
6162 /*
6163  * Figure out the LHS type and other properties for an assignment or one item
6164  * of ":unlet" with an index.
6165  * Returns OK or FAIL.
6166  */
6167     static int
6168 compile_lhs(
6169 	char_u	*var_start,
6170 	lhs_T	*lhs,
6171 	int	cmdidx,
6172 	int	heredoc,
6173 	int	oplen,
6174 	cctx_T	*cctx)
6175 {
6176     char_u	*var_end;
6177     int		is_decl = is_decl_command(cmdidx);
6178 
6179     CLEAR_POINTER(lhs);
6180     lhs->lhs_dest = dest_local;
6181     lhs->lhs_vimvaridx = -1;
6182     lhs->lhs_scriptvar_idx = -1;
6183 
6184     // "dest_end" is the end of the destination, including "[expr]" or
6185     // ".name".
6186     // "var_end" is the end of the variable/option/etc. name.
6187     lhs->lhs_dest_end = skip_var_one(var_start, FALSE);
6188     if (*var_start == '@')
6189 	var_end = var_start + 2;
6190     else
6191     {
6192 	// skip over the leading "&", "&l:", "&g:" and "$"
6193 	var_end = skip_option_env_lead(var_start);
6194 	var_end = to_name_end(var_end, TRUE);
6195     }
6196 
6197     // "a: type" is declaring variable "a" with a type, not dict "a:".
6198     if (is_decl && lhs->lhs_dest_end == var_start + 2
6199 					       && lhs->lhs_dest_end[-1] == ':')
6200 	--lhs->lhs_dest_end;
6201     if (is_decl && var_end == var_start + 2 && var_end[-1] == ':')
6202 	--var_end;
6203 
6204     // compute the length of the destination without "[expr]" or ".name"
6205     lhs->lhs_varlen = var_end - var_start;
6206     lhs->lhs_varlen_total = lhs->lhs_varlen;
6207     lhs->lhs_name = vim_strnsave(var_start, lhs->lhs_varlen);
6208     if (lhs->lhs_name == NULL)
6209 	return FAIL;
6210 
6211     if (lhs->lhs_dest_end > var_start + lhs->lhs_varlen)
6212 	// Something follows after the variable: "var[idx]" or "var.key".
6213 	lhs->lhs_has_index = TRUE;
6214 
6215     if (heredoc)
6216 	lhs->lhs_type = &t_list_string;
6217     else
6218 	lhs->lhs_type = &t_any;
6219 
6220     if (cctx->ctx_skip != SKIP_YES)
6221     {
6222 	int	    declare_error = FALSE;
6223 
6224 	if (get_var_dest(lhs->lhs_name, &lhs->lhs_dest, cmdidx,
6225 				      &lhs->lhs_opt_flags, &lhs->lhs_vimvaridx,
6226 						 &lhs->lhs_type, cctx) == FAIL)
6227 	    return FAIL;
6228 	if (lhs->lhs_dest != dest_local
6229 				 && cmdidx != CMD_const && cmdidx != CMD_final)
6230 	{
6231 	    // Specific kind of variable recognized.
6232 	    declare_error = is_decl;
6233 	}
6234 	else
6235 	{
6236 	    // No specific kind of variable recognized, just a name.
6237 	    if (check_reserved_name(lhs->lhs_name) == FAIL)
6238 		return FAIL;
6239 
6240 	    if (lookup_local(var_start, lhs->lhs_varlen,
6241 					     &lhs->lhs_local_lvar, cctx) == OK)
6242 		lhs->lhs_lvar = &lhs->lhs_local_lvar;
6243 	    else
6244 	    {
6245 		CLEAR_FIELD(lhs->lhs_arg_lvar);
6246 		if (arg_exists(var_start, lhs->lhs_varlen,
6247 			 &lhs->lhs_arg_lvar.lv_idx, &lhs->lhs_arg_lvar.lv_type,
6248 			    &lhs->lhs_arg_lvar.lv_from_outer, cctx) == OK)
6249 		{
6250 		    if (is_decl)
6251 		    {
6252 			semsg(_(e_str_is_used_as_argument), lhs->lhs_name);
6253 			return FAIL;
6254 		    }
6255 		    lhs->lhs_lvar = &lhs->lhs_arg_lvar;
6256 		}
6257 	    }
6258 	    if (lhs->lhs_lvar != NULL)
6259 	    {
6260 		if (is_decl)
6261 		{
6262 		    semsg(_(e_variable_already_declared), lhs->lhs_name);
6263 		    return FAIL;
6264 		}
6265 	    }
6266 	    else
6267 	    {
6268 		int script_namespace = lhs->lhs_varlen > 1
6269 				       && STRNCMP(var_start, "s:", 2) == 0;
6270 		int script_var = (script_namespace
6271 			? script_var_exists(var_start + 2, lhs->lhs_varlen - 2,
6272 									  cctx)
6273 			  : script_var_exists(var_start, lhs->lhs_varlen,
6274 								  cctx)) == OK;
6275 		imported_T  *import =
6276 			       find_imported(var_start, lhs->lhs_varlen, cctx);
6277 
6278 		if (script_namespace || script_var || import != NULL)
6279 		{
6280 		    char_u	*rawname = lhs->lhs_name
6281 					   + (lhs->lhs_name[1] == ':' ? 2 : 0);
6282 
6283 		    if (is_decl)
6284 		    {
6285 			if (script_namespace)
6286 			    semsg(_(e_cannot_declare_script_variable_in_function),
6287 								lhs->lhs_name);
6288 			else
6289 			    semsg(_(e_variable_already_declared_in_script_str),
6290 								lhs->lhs_name);
6291 			return FAIL;
6292 		    }
6293 		    else if (cctx->ctx_ufunc->uf_script_ctx_version
6294 							 == SCRIPT_VERSION_VIM9
6295 				    && script_namespace
6296 				    && !script_var && import == NULL)
6297 		    {
6298 			semsg(_(e_unknown_variable_str), lhs->lhs_name);
6299 			return FAIL;
6300 		    }
6301 
6302 		    lhs->lhs_dest = dest_script;
6303 
6304 		    // existing script-local variables should have a type
6305 		    lhs->lhs_scriptvar_sid = current_sctx.sc_sid;
6306 		    if (import != NULL)
6307 			lhs->lhs_scriptvar_sid = import->imp_sid;
6308 		    if (SCRIPT_ID_VALID(lhs->lhs_scriptvar_sid))
6309 		    {
6310 			// Check writable only when no index follows.
6311 			lhs->lhs_scriptvar_idx = get_script_item_idx(
6312 					       lhs->lhs_scriptvar_sid, rawname,
6313 			      lhs->lhs_has_index ? ASSIGN_FINAL : ASSIGN_CONST,
6314 									 cctx);
6315 			if (lhs->lhs_scriptvar_idx >= 0)
6316 			{
6317 			    scriptitem_T *si = SCRIPT_ITEM(
6318 						       lhs->lhs_scriptvar_sid);
6319 			    svar_T	 *sv =
6320 					    ((svar_T *)si->sn_var_vals.ga_data)
6321 						      + lhs->lhs_scriptvar_idx;
6322 			    lhs->lhs_type = sv->sv_type;
6323 			}
6324 		    }
6325 		}
6326 		else if (check_defined(var_start, lhs->lhs_varlen, cctx, FALSE)
6327 								       == FAIL)
6328 		    return FAIL;
6329 	    }
6330 	}
6331 
6332 	if (declare_error)
6333 	{
6334 	    vim9_declare_error(lhs->lhs_name);
6335 	    return FAIL;
6336 	}
6337     }
6338 
6339     // handle "a:name" as a name, not index "name" on "a"
6340     if (lhs->lhs_varlen > 1 || var_start[lhs->lhs_varlen] != ':')
6341 	var_end = lhs->lhs_dest_end;
6342 
6343     if (lhs->lhs_dest != dest_option)
6344     {
6345 	if (is_decl && *var_end == ':')
6346 	{
6347 	    char_u *p;
6348 
6349 	    // parse optional type: "let var: type = expr"
6350 	    if (!VIM_ISWHITE(var_end[1]))
6351 	    {
6352 		semsg(_(e_white_space_required_after_str_str), ":", var_end);
6353 		return FAIL;
6354 	    }
6355 	    p = skipwhite(var_end + 1);
6356 	    lhs->lhs_type = parse_type(&p, cctx->ctx_type_list, TRUE);
6357 	    if (lhs->lhs_type == NULL)
6358 		return FAIL;
6359 	    lhs->lhs_has_type = TRUE;
6360 	}
6361 	else if (lhs->lhs_lvar != NULL)
6362 	    lhs->lhs_type = lhs->lhs_lvar->lv_type;
6363     }
6364 
6365     if (oplen == 3 && !heredoc
6366 		   && lhs->lhs_dest != dest_global
6367 		   && !lhs->lhs_has_index
6368 		   && lhs->lhs_type->tt_type != VAR_STRING
6369 		   && lhs->lhs_type->tt_type != VAR_ANY)
6370     {
6371 	emsg(_(e_can_only_concatenate_to_string));
6372 	return FAIL;
6373     }
6374 
6375     if (lhs->lhs_lvar == NULL && lhs->lhs_dest == dest_local
6376 						 && cctx->ctx_skip != SKIP_YES)
6377     {
6378 	if (oplen > 1 && !heredoc)
6379 	{
6380 	    // +=, /=, etc. require an existing variable
6381 	    semsg(_(e_cannot_use_operator_on_new_variable), lhs->lhs_name);
6382 	    return FAIL;
6383 	}
6384 	if (!is_decl)
6385 	{
6386 	    semsg(_(e_unknown_variable_str), lhs->lhs_name);
6387 	    return FAIL;
6388 	}
6389 
6390 	// Check the name is valid for a funcref.
6391 	if ((lhs->lhs_type->tt_type == VAR_FUNC
6392 				      || lhs->lhs_type->tt_type == VAR_PARTIAL)
6393 		&& var_wrong_func_name(lhs->lhs_name, TRUE))
6394 	    return FAIL;
6395 
6396 	// New local variable.
6397 	lhs->lhs_lvar = reserve_local(cctx, var_start, lhs->lhs_varlen,
6398 		    cmdidx == CMD_final || cmdidx == CMD_const, lhs->lhs_type);
6399 	if (lhs->lhs_lvar == NULL)
6400 	    return FAIL;
6401 	lhs->lhs_new_local = TRUE;
6402     }
6403 
6404     lhs->lhs_member_type = lhs->lhs_type;
6405     if (lhs->lhs_has_index)
6406     {
6407 	// Something follows after the variable: "var[idx]" or "var.key".
6408 	// TODO: should we also handle "->func()" here?
6409 	if (is_decl)
6410 	{
6411 	    emsg(_(e_cannot_use_index_when_declaring_variable));
6412 	    return FAIL;
6413 	}
6414 
6415 	if (var_start[lhs->lhs_varlen] == '['
6416 					  || var_start[lhs->lhs_varlen] == '.')
6417 	{
6418 	    char_u	*after = var_start + lhs->lhs_varlen;
6419 	    char_u	*p;
6420 
6421 	    // Only the last index is used below, if there are others
6422 	    // before it generate code for the expression.  Thus for
6423 	    // "ll[1][2]" the expression is "ll[1]" and "[2]" is the index.
6424 	    for (;;)
6425 	    {
6426 		p = skip_index(after);
6427 		if (*p != '[' && *p != '.')
6428 		{
6429 		    lhs->lhs_varlen_total = p - var_start;
6430 		    break;
6431 		}
6432 		after = p;
6433 	    }
6434 	    if (after > var_start + lhs->lhs_varlen)
6435 	    {
6436 		lhs->lhs_varlen = after - var_start;
6437 		lhs->lhs_dest = dest_expr;
6438 		// We don't know the type before evaluating the expression,
6439 		// use "any" until then.
6440 		lhs->lhs_type = &t_any;
6441 	    }
6442 
6443 	    if (lhs->lhs_type->tt_member == NULL)
6444 		lhs->lhs_member_type = &t_any;
6445 	    else
6446 		lhs->lhs_member_type = lhs->lhs_type->tt_member;
6447 	}
6448 	else
6449 	{
6450 	    semsg("Not supported yet: %s", var_start);
6451 	    return FAIL;
6452 	}
6453     }
6454     return OK;
6455 }
6456 
6457 /*
6458  * Figure out the LHS and check a few errors.
6459  */
6460     static int
6461 compile_assign_lhs(
6462 	char_u	*var_start,
6463 	lhs_T	*lhs,
6464 	int	cmdidx,
6465 	int	is_decl,
6466 	int	heredoc,
6467 	int	oplen,
6468 	cctx_T	*cctx)
6469 {
6470     if (compile_lhs(var_start, lhs, cmdidx, heredoc, oplen, cctx) == FAIL)
6471 	return FAIL;
6472 
6473     if (!lhs->lhs_has_index && lhs->lhs_lvar == &lhs->lhs_arg_lvar)
6474     {
6475 	semsg(_(e_cannot_assign_to_argument), lhs->lhs_name);
6476 	return FAIL;
6477     }
6478     if (!is_decl && lhs->lhs_lvar != NULL
6479 			   && lhs->lhs_lvar->lv_const && !lhs->lhs_has_index)
6480     {
6481 	semsg(_(e_cannot_assign_to_constant), lhs->lhs_name);
6482 	return FAIL;
6483     }
6484     return OK;
6485 }
6486 
6487 /*
6488  * Return TRUE if "lhs" has a range index: "[expr : expr]".
6489  */
6490     static int
6491 has_list_index(char_u *idx_start, cctx_T *cctx)
6492 {
6493     char_u  *p = idx_start;
6494     int	    save_skip;
6495 
6496     if (*p != '[')
6497 	return FALSE;
6498 
6499     p = skipwhite(p + 1);
6500     if (*p == ':')
6501 	return TRUE;
6502 
6503     save_skip = cctx->ctx_skip;
6504     cctx->ctx_skip = SKIP_YES;
6505     (void)compile_expr0(&p, cctx);
6506     cctx->ctx_skip = save_skip;
6507     return *skipwhite(p) == ':';
6508 }
6509 
6510 /*
6511  * For an assignment with an index, compile the "idx" in "var[idx]" or "key" in
6512  * "var.key".
6513  */
6514     static int
6515 compile_assign_index(
6516 	char_u	*var_start,
6517 	lhs_T	*lhs,
6518 	int	*range,
6519 	cctx_T	*cctx)
6520 {
6521     size_t	varlen = lhs->lhs_varlen;
6522     char_u	*p;
6523     int		r = OK;
6524     int		need_white_before = TRUE;
6525     int		empty_second;
6526 
6527     p = var_start + varlen;
6528     if (*p == '[')
6529     {
6530 	p = skipwhite(p + 1);
6531 	if (*p == ':')
6532 	{
6533 	    // empty first index, push zero
6534 	    r = generate_PUSHNR(cctx, 0);
6535 	    need_white_before = FALSE;
6536 	}
6537 	else
6538 	    r = compile_expr0(&p, cctx);
6539 
6540 	if (r == OK && *skipwhite(p) == ':')
6541 	{
6542 	    // unlet var[idx : idx]
6543 	    // blob[idx : idx] = value
6544 	    *range = TRUE;
6545 	    p = skipwhite(p);
6546 	    empty_second = *skipwhite(p + 1) == ']';
6547 	    if ((need_white_before && !IS_WHITE_OR_NUL(p[-1]))
6548 		    || (!empty_second && !IS_WHITE_OR_NUL(p[1])))
6549 	    {
6550 		semsg(_(e_white_space_required_before_and_after_str_at_str),
6551 								      ":", p);
6552 		return FAIL;
6553 	    }
6554 	    p = skipwhite(p + 1);
6555 	    if (*p == ']')
6556 		// empty second index, push "none"
6557 		r = generate_PUSHSPEC(cctx, VVAL_NONE);
6558 	    else
6559 		r = compile_expr0(&p, cctx);
6560 	}
6561 
6562 	if (r == OK && *skipwhite(p) != ']')
6563 	{
6564 	    // this should not happen
6565 	    emsg(_(e_missbrac));
6566 	    r = FAIL;
6567 	}
6568     }
6569     else // if (*p == '.')
6570     {
6571 	char_u *key_end = to_name_end(p + 1, TRUE);
6572 	char_u *key = vim_strnsave(p + 1, key_end - p - 1);
6573 
6574 	r = generate_PUSHS(cctx, &key);
6575     }
6576     return r;
6577 }
6578 
6579 /*
6580  * For a LHS with an index, load the variable to be indexed.
6581  */
6582     static int
6583 compile_load_lhs(
6584 	lhs_T	*lhs,
6585 	char_u	*var_start,
6586 	type_T	*rhs_type,
6587 	cctx_T	*cctx)
6588 {
6589     if (lhs->lhs_dest == dest_expr)
6590     {
6591 	size_t	    varlen = lhs->lhs_varlen;
6592 	int	    c = var_start[varlen];
6593 	int	    lines_len = cctx->ctx_ufunc->uf_lines.ga_len;
6594 	char_u	    *p = var_start;
6595 	garray_T    *stack = &cctx->ctx_type_stack;
6596 	int	    res;
6597 
6598 	// Evaluate "ll[expr]" of "ll[expr][idx]".  End the line with a NUL and
6599 	// limit the lines array length to avoid skipping to a following line.
6600 	var_start[varlen] = NUL;
6601 	cctx->ctx_ufunc->uf_lines.ga_len = cctx->ctx_lnum + 1;
6602 	res = compile_expr0(&p, cctx);
6603 	var_start[varlen] = c;
6604 	cctx->ctx_ufunc->uf_lines.ga_len = lines_len;
6605 	if (res == FAIL || p != var_start + varlen)
6606 	{
6607 	    // this should not happen
6608 	    if (res != FAIL)
6609 		emsg(_(e_missbrac));
6610 	    return FAIL;
6611 	}
6612 
6613 	lhs->lhs_type = stack->ga_len == 0 ? &t_void
6614 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
6615 	// now we can properly check the type
6616 	if (rhs_type != NULL && lhs->lhs_type->tt_member != NULL
6617 		&& rhs_type != &t_void
6618 		&& need_type(rhs_type, lhs->lhs_type->tt_member, -2, 0, cctx,
6619 							 FALSE, FALSE) == FAIL)
6620 	    return FAIL;
6621     }
6622     else
6623 	generate_loadvar(cctx, lhs->lhs_dest, lhs->lhs_name,
6624 						 lhs->lhs_lvar, lhs->lhs_type);
6625     return OK;
6626 }
6627 
6628 /*
6629  * Produce code for loading "lhs" and also take care of an index.
6630  * Return OK/FAIL.
6631  */
6632     static int
6633 compile_load_lhs_with_index(lhs_T *lhs, char_u *var_start, cctx_T *cctx)
6634 {
6635     compile_load_lhs(lhs, var_start, NULL, cctx);
6636 
6637     if (lhs->lhs_has_index)
6638     {
6639 	int range = FALSE;
6640 
6641 	// Get member from list or dict.  First compile the
6642 	// index value.
6643 	if (compile_assign_index(var_start, lhs, &range, cctx) == FAIL)
6644 	    return FAIL;
6645 	if (range)
6646 	{
6647 	    semsg(_(e_cannot_use_range_with_assignment_operator_str),
6648 								    var_start);
6649 	    return FAIL;
6650 	}
6651 
6652 	// Get the member.
6653 	if (compile_member(FALSE, cctx) == FAIL)
6654 	    return FAIL;
6655     }
6656     return OK;
6657 }
6658 
6659 /*
6660  * Assignment to a list or dict member, or ":unlet" for the item, using the
6661  * information in "lhs".
6662  * Returns OK or FAIL.
6663  */
6664     static int
6665 compile_assign_unlet(
6666 	char_u	*var_start,
6667 	lhs_T	*lhs,
6668 	int	is_assign,
6669 	type_T	*rhs_type,
6670 	cctx_T	*cctx)
6671 {
6672     vartype_T	dest_type;
6673     garray_T    *stack = &cctx->ctx_type_stack;
6674     int		range = FALSE;
6675 
6676     if (compile_assign_index(var_start, lhs, &range, cctx) == FAIL)
6677 	return FAIL;
6678     if (is_assign && range
6679 	    && lhs->lhs_type->tt_type != VAR_LIST
6680 	    && lhs->lhs_type != &t_blob
6681 	    && lhs->lhs_type != &t_any)
6682     {
6683 	semsg(_(e_cannot_use_range_with_assignment_str), var_start);
6684 	return FAIL;
6685     }
6686 
6687     if (lhs->lhs_type == &t_any)
6688     {
6689 	// Index on variable of unknown type: check at runtime.
6690 	dest_type = VAR_ANY;
6691     }
6692     else
6693     {
6694 	dest_type = lhs->lhs_type->tt_type;
6695 	if (dest_type == VAR_DICT && range)
6696 	{
6697 	    emsg(e_cannot_use_range_with_dictionary);
6698 	    return FAIL;
6699 	}
6700 	if (dest_type == VAR_DICT
6701 			      && may_generate_2STRING(-1, FALSE, cctx) == FAIL)
6702 	    return FAIL;
6703 	if (dest_type == VAR_LIST || dest_type == VAR_BLOB)
6704 	{
6705 	    type_T *type;
6706 
6707 	    if (range)
6708 	    {
6709 		type = ((type_T **)stack->ga_data)[stack->ga_len - 2];
6710 		if (need_type(type, &t_number,
6711 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
6712 		return FAIL;
6713 	    }
6714 	    type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
6715 	    if ((dest_type != VAR_BLOB && type != &t_special)
6716 		    && need_type(type, &t_number,
6717 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
6718 		return FAIL;
6719 	}
6720     }
6721 
6722     // Load the dict or list.  On the stack we then have:
6723     // - value (for assignment, not for :unlet)
6724     // - index
6725     // - for [a : b] second index
6726     // - variable
6727     if (compile_load_lhs(lhs, var_start, rhs_type, cctx) == FAIL)
6728 	return FAIL;
6729 
6730     if (dest_type == VAR_LIST || dest_type == VAR_DICT
6731 			      || dest_type == VAR_BLOB || dest_type == VAR_ANY)
6732     {
6733 	if (is_assign)
6734 	{
6735 	    if (range)
6736 	    {
6737 		if (generate_instr_drop(cctx, ISN_STORERANGE, 4) == NULL)
6738 		    return FAIL;
6739 	    }
6740 	    else
6741 	    {
6742 		isn_T	*isn = generate_instr_drop(cctx, ISN_STOREINDEX, 3);
6743 
6744 		if (isn == NULL)
6745 		    return FAIL;
6746 		isn->isn_arg.vartype = dest_type;
6747 	    }
6748 	}
6749 	else if (range)
6750 	{
6751 	    if (generate_instr_drop(cctx, ISN_UNLETRANGE, 3) == NULL)
6752 		return FAIL;
6753 	}
6754 	else
6755 	{
6756 	    if (generate_instr_drop(cctx, ISN_UNLETINDEX, 2) == NULL)
6757 		return FAIL;
6758 	}
6759     }
6760     else
6761     {
6762 	emsg(_(e_indexable_type_required));
6763 	return FAIL;
6764     }
6765 
6766     return OK;
6767 }
6768 
6769 /*
6770  * Compile declaration and assignment:
6771  * "let name"
6772  * "var name = expr"
6773  * "final name = expr"
6774  * "const name = expr"
6775  * "name = expr"
6776  * "arg" points to "name".
6777  * "++arg" and "--arg"
6778  * Return NULL for an error.
6779  * Return "arg" if it does not look like a variable list.
6780  */
6781     static char_u *
6782 compile_assignment(char_u *arg, exarg_T *eap, cmdidx_T cmdidx, cctx_T *cctx)
6783 {
6784     char_u	*var_start;
6785     char_u	*p;
6786     char_u	*end = arg;
6787     char_u	*ret = NULL;
6788     int		var_count = 0;
6789     int		var_idx;
6790     int		semicolon = 0;
6791     int		did_generate_slice = FALSE;
6792     garray_T	*instr = &cctx->ctx_instr;
6793     garray_T    *stack = &cctx->ctx_type_stack;
6794     char_u	*op;
6795     int		oplen = 0;
6796     int		heredoc = FALSE;
6797     int		incdec = FALSE;
6798     type_T	*rhs_type = &t_any;
6799     char_u	*sp;
6800     int		is_decl = is_decl_command(cmdidx);
6801     lhs_T	lhs;
6802     long	start_lnum = SOURCING_LNUM;
6803 
6804     // Skip over the "var" or "[var, var]" to get to any "=".
6805     p = skip_var_list(arg, TRUE, &var_count, &semicolon, TRUE);
6806     if (p == NULL)
6807 	return *arg == '[' ? arg : NULL;
6808 
6809     if (var_count > 0 && is_decl)
6810     {
6811 	// TODO: should we allow this, and figure out type inference from list
6812 	// members?
6813 	emsg(_(e_cannot_use_list_for_declaration));
6814 	return NULL;
6815     }
6816     lhs.lhs_name = NULL;
6817 
6818     sp = p;
6819     p = skipwhite(p);
6820     op = p;
6821     oplen = assignment_len(p, &heredoc);
6822 
6823     if (var_count > 0 && oplen == 0)
6824 	// can be something like "[1, 2]->func()"
6825 	return arg;
6826 
6827     if (oplen > 0 && (!VIM_ISWHITE(*sp) || !IS_WHITE_OR_NUL(op[oplen])))
6828     {
6829 	error_white_both(op, oplen);
6830 	return NULL;
6831     }
6832     if (eap->cmdidx == CMD_increment || eap->cmdidx == CMD_decrement)
6833     {
6834 	if (VIM_ISWHITE(eap->cmd[2]))
6835 	{
6836 	    semsg(_(e_no_white_space_allowed_after_str_str),
6837 			 eap->cmdidx == CMD_increment ? "++" : "--", eap->cmd);
6838 	    return NULL;
6839 	}
6840 	op = (char_u *)(eap->cmdidx == CMD_increment ? "+=" : "-=");
6841 	oplen = 2;
6842 	incdec = TRUE;
6843     }
6844 
6845     if (heredoc)
6846     {
6847 	list_T	   *l;
6848 	listitem_T *li;
6849 
6850 	// [let] varname =<< [trim] {end}
6851 	eap->getline = exarg_getline;
6852 	eap->cookie = cctx;
6853 	l = heredoc_get(eap, op + 3, FALSE);
6854 	if (l == NULL)
6855 	    return NULL;
6856 
6857 	if (cctx->ctx_skip != SKIP_YES)
6858 	{
6859 	    // Push each line and the create the list.
6860 	    FOR_ALL_LIST_ITEMS(l, li)
6861 	    {
6862 		generate_PUSHS(cctx, &li->li_tv.vval.v_string);
6863 		li->li_tv.vval.v_string = NULL;
6864 	    }
6865 	    generate_NEWLIST(cctx, l->lv_len);
6866 	}
6867 	list_free(l);
6868 	p += STRLEN(p);
6869 	end = p;
6870     }
6871     else if (var_count > 0)
6872     {
6873 	char_u *wp;
6874 
6875 	// for "[var, var] = expr" evaluate the expression here, loop over the
6876 	// list of variables below.
6877 	// A line break may follow the "=".
6878 
6879 	wp = op + oplen;
6880 	if (may_get_next_line_error(wp, &p, cctx) == FAIL)
6881 	    return FAIL;
6882 	if (compile_expr0(&p, cctx) == FAIL)
6883 	    return NULL;
6884 	end = p;
6885 
6886 	if (cctx->ctx_skip != SKIP_YES)
6887 	{
6888 	    type_T	*stacktype;
6889 
6890 	    stacktype = stack->ga_len == 0 ? &t_void
6891 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
6892 	    if (stacktype->tt_type == VAR_VOID)
6893 	    {
6894 		emsg(_(e_cannot_use_void_value));
6895 		goto theend;
6896 	    }
6897 	    if (need_type(stacktype, &t_list_any, -1, 0, cctx,
6898 							 FALSE, FALSE) == FAIL)
6899 		goto theend;
6900 	    // TODO: check the length of a constant list here
6901 	    generate_CHECKLEN(cctx, semicolon ? var_count - 1 : var_count,
6902 								    semicolon);
6903 	    if (stacktype->tt_member != NULL)
6904 		rhs_type = stacktype->tt_member;
6905 	}
6906     }
6907 
6908     /*
6909      * Loop over variables in "[var, var] = expr".
6910      * For "var = expr" and "let var: type" this is done only once.
6911      */
6912     if (var_count > 0)
6913 	var_start = skipwhite(arg + 1);  // skip over the "["
6914     else
6915 	var_start = arg;
6916     for (var_idx = 0; var_idx == 0 || var_idx < var_count; var_idx++)
6917     {
6918 	int	instr_count = -1;
6919 	int	save_lnum;
6920 
6921 	if (var_start[0] == '_' && !eval_isnamec(var_start[1]))
6922 	{
6923 	    // Ignore underscore in "[a, _, b] = list".
6924 	    if (var_count > 0)
6925 	    {
6926 		var_start = skipwhite(var_start + 2);
6927 		continue;
6928 	    }
6929 	    emsg(_(e_cannot_use_underscore_here));
6930 	    goto theend;
6931 	}
6932 	vim_free(lhs.lhs_name);
6933 
6934 	/*
6935 	 * Figure out the LHS type and other properties.
6936 	 */
6937 	if (compile_assign_lhs(var_start, &lhs, cmdidx,
6938 					is_decl, heredoc, oplen, cctx) == FAIL)
6939 	    goto theend;
6940 	if (heredoc)
6941 	{
6942 	    SOURCING_LNUM = start_lnum;
6943 	    if (lhs.lhs_has_type
6944 		    && need_type(&t_list_string, lhs.lhs_type,
6945 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
6946 		goto theend;
6947 	}
6948 	else
6949 	{
6950 	    if (cctx->ctx_skip == SKIP_YES)
6951 	    {
6952 		if (oplen > 0 && var_count == 0)
6953 		{
6954 		    // skip over the "=" and the expression
6955 		    p = skipwhite(op + oplen);
6956 		    (void)compile_expr0(&p, cctx);
6957 		}
6958 	    }
6959 	    else if (oplen > 0)
6960 	    {
6961 		int	is_const = FALSE;
6962 		char_u	*wp;
6963 
6964 		// for "+=", "*=", "..=" etc. first load the current value
6965 		if (*op != '='
6966 			&& compile_load_lhs_with_index(&lhs, var_start,
6967 								 cctx) == FAIL)
6968 		    goto theend;
6969 
6970 		// For "var = expr" evaluate the expression.
6971 		if (var_count == 0)
6972 		{
6973 		    int	r;
6974 
6975 		    // Compile the expression.
6976 		    instr_count = instr->ga_len;
6977 		    if (incdec)
6978 		    {
6979 			r = generate_PUSHNR(cctx, 1);
6980 		    }
6981 		    else
6982 		    {
6983 			// Temporarily hide the new local variable here, it is
6984 			// not available to this expression.
6985 			if (lhs.lhs_new_local)
6986 			    --cctx->ctx_locals.ga_len;
6987 			wp = op + oplen;
6988 			if (may_get_next_line_error(wp, &p, cctx) == FAIL)
6989 			{
6990 			    if (lhs.lhs_new_local)
6991 				++cctx->ctx_locals.ga_len;
6992 			    goto theend;
6993 			}
6994 			r = compile_expr0_ext(&p, cctx, &is_const);
6995 			if (lhs.lhs_new_local)
6996 			    ++cctx->ctx_locals.ga_len;
6997 			if (r == FAIL)
6998 			    goto theend;
6999 		    }
7000 		}
7001 		else if (semicolon && var_idx == var_count - 1)
7002 		{
7003 		    // For "[var; var] = expr" get the rest of the list
7004 		    did_generate_slice = TRUE;
7005 		    if (generate_SLICE(cctx, var_count - 1) == FAIL)
7006 			goto theend;
7007 		}
7008 		else
7009 		{
7010 		    // For "[var, var] = expr" get the "var_idx" item from the
7011 		    // list.
7012 		    if (generate_GETITEM(cctx, var_idx, *op != '=') == FAIL)
7013 			goto theend;
7014 		}
7015 
7016 		rhs_type = stack->ga_len == 0 ? &t_void
7017 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
7018 		if (lhs.lhs_lvar != NULL && (is_decl || !lhs.lhs_has_type))
7019 		{
7020 		    if ((rhs_type->tt_type == VAR_FUNC
7021 				|| rhs_type->tt_type == VAR_PARTIAL)
7022 			    && !lhs.lhs_has_index
7023 			    && var_wrong_func_name(lhs.lhs_name, TRUE))
7024 			goto theend;
7025 
7026 		    if (lhs.lhs_new_local && !lhs.lhs_has_type)
7027 		    {
7028 			if (rhs_type->tt_type == VAR_VOID)
7029 			{
7030 			    emsg(_(e_cannot_use_void_value));
7031 			    goto theend;
7032 			}
7033 			else
7034 			{
7035 			    // An empty list or dict has a &t_unknown member,
7036 			    // for a variable that implies &t_any.
7037 			    if (rhs_type == &t_list_empty)
7038 				lhs.lhs_lvar->lv_type = &t_list_any;
7039 			    else if (rhs_type == &t_dict_empty)
7040 				lhs.lhs_lvar->lv_type = &t_dict_any;
7041 			    else if (rhs_type == &t_unknown)
7042 				lhs.lhs_lvar->lv_type = &t_any;
7043 			    else
7044 				lhs.lhs_lvar->lv_type = rhs_type;
7045 			}
7046 		    }
7047 		    else if (*op == '=')
7048 		    {
7049 			type_T *use_type = lhs.lhs_lvar->lv_type;
7050 			where_T where = WHERE_INIT;
7051 
7052 			// Without operator check type here, otherwise below.
7053 			// Use the line number of the assignment.
7054 			SOURCING_LNUM = start_lnum;
7055 			where.wt_index = var_count > 0 ? var_idx + 1 : 0;
7056 			where.wt_variable = var_count > 0;
7057 			// If assigning to a list or dict member, use the
7058 			// member type.  Not for "list[:] =".
7059 			if (lhs.lhs_has_index
7060 				&& !has_list_index(var_start + lhs.lhs_varlen,
7061 									 cctx))
7062 			    use_type = lhs.lhs_member_type;
7063 			if (need_type_where(rhs_type, use_type, -1, where,
7064 				    cctx, FALSE, is_const) == FAIL)
7065 			    goto theend;
7066 		    }
7067 		}
7068 		else
7069 		{
7070 		    type_T *lhs_type = lhs.lhs_member_type;
7071 
7072 		    // Special case: assigning to @# can use a number or a
7073 		    // string.
7074 		    // Also: can assign a number to a float.
7075 		    if ((lhs_type == &t_number_or_string
7076 				|| lhs_type == &t_float)
7077 			    && rhs_type->tt_type == VAR_NUMBER)
7078 			lhs_type = &t_number;
7079 		    if (*p != '=' && need_type(rhs_type, lhs_type,
7080 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
7081 		    goto theend;
7082 		}
7083 	    }
7084 	    else if (cmdidx == CMD_final)
7085 	    {
7086 		emsg(_(e_final_requires_a_value));
7087 		goto theend;
7088 	    }
7089 	    else if (cmdidx == CMD_const)
7090 	    {
7091 		emsg(_(e_const_requires_a_value));
7092 		goto theend;
7093 	    }
7094 	    else if (!lhs.lhs_has_type || lhs.lhs_dest == dest_option)
7095 	    {
7096 		emsg(_(e_type_or_initialization_required));
7097 		goto theend;
7098 	    }
7099 	    else
7100 	    {
7101 		// variables are always initialized
7102 		if (GA_GROW_FAILS(instr, 1))
7103 		    goto theend;
7104 		switch (lhs.lhs_member_type->tt_type)
7105 		{
7106 		    case VAR_BOOL:
7107 			generate_PUSHBOOL(cctx, VVAL_FALSE);
7108 			break;
7109 		    case VAR_FLOAT:
7110 #ifdef FEAT_FLOAT
7111 			generate_PUSHF(cctx, 0.0);
7112 #endif
7113 			break;
7114 		    case VAR_STRING:
7115 			generate_PUSHS(cctx, NULL);
7116 			break;
7117 		    case VAR_BLOB:
7118 			generate_PUSHBLOB(cctx, blob_alloc());
7119 			break;
7120 		    case VAR_FUNC:
7121 			generate_PUSHFUNC(cctx, NULL, &t_func_void);
7122 			break;
7123 		    case VAR_LIST:
7124 			generate_NEWLIST(cctx, 0);
7125 			break;
7126 		    case VAR_DICT:
7127 			generate_NEWDICT(cctx, 0);
7128 			break;
7129 		    case VAR_JOB:
7130 			generate_PUSHJOB(cctx, NULL);
7131 			break;
7132 		    case VAR_CHANNEL:
7133 			generate_PUSHCHANNEL(cctx, NULL);
7134 			break;
7135 		    case VAR_NUMBER:
7136 		    case VAR_UNKNOWN:
7137 		    case VAR_ANY:
7138 		    case VAR_PARTIAL:
7139 		    case VAR_VOID:
7140 		    case VAR_INSTR:
7141 		    case VAR_SPECIAL:  // cannot happen
7142 			generate_PUSHNR(cctx, 0);
7143 			break;
7144 		}
7145 	    }
7146 	    if (var_count == 0)
7147 		end = p;
7148 	}
7149 
7150 	// no need to parse more when skipping
7151 	if (cctx->ctx_skip == SKIP_YES)
7152 	    break;
7153 
7154 	if (oplen > 0 && *op != '=')
7155 	{
7156 	    type_T	    *expected;
7157 	    type_T	    *stacktype = NULL;
7158 
7159 	    if (*op == '.')
7160 	    {
7161 		if (may_generate_2STRING(-1, FALSE, cctx) == FAIL)
7162 		    goto theend;
7163 	    }
7164 	    else
7165 	    {
7166 		expected = lhs.lhs_member_type;
7167 		stacktype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
7168 		if (
7169 #ifdef FEAT_FLOAT
7170 		    // If variable is float operation with number is OK.
7171 		    !(expected == &t_float && (stacktype == &t_number
7172 			    || stacktype == &t_number_bool)) &&
7173 #endif
7174 		    need_type(stacktype, expected, -1, 0, cctx,
7175 							 FALSE, FALSE) == FAIL)
7176 		    goto theend;
7177 	    }
7178 
7179 	    if (*op == '.')
7180 	    {
7181 		if (generate_instr_drop(cctx, ISN_CONCAT, 1) == NULL)
7182 		    goto theend;
7183 	    }
7184 	    else if (*op == '+')
7185 	    {
7186 		if (generate_add_instr(cctx,
7187 			    operator_type(lhs.lhs_member_type, stacktype),
7188 				       lhs.lhs_member_type, stacktype) == FAIL)
7189 		    goto theend;
7190 	    }
7191 	    else if (generate_two_op(cctx, op) == FAIL)
7192 		goto theend;
7193 	}
7194 
7195 	// Use the line number of the assignment for store instruction.
7196 	save_lnum = cctx->ctx_lnum;
7197 	cctx->ctx_lnum = start_lnum - 1;
7198 
7199 	if (lhs.lhs_has_index)
7200 	{
7201 	    // Use the info in "lhs" to store the value at the index in the
7202 	    // list or dict.
7203 	    if (compile_assign_unlet(var_start, &lhs, TRUE, rhs_type, cctx)
7204 								       == FAIL)
7205 	    {
7206 		cctx->ctx_lnum = save_lnum;
7207 		goto theend;
7208 	    }
7209 	}
7210 	else
7211 	{
7212 	    if (is_decl && cmdidx == CMD_const && (lhs.lhs_dest == dest_script
7213 						|| lhs.lhs_dest == dest_global
7214 						|| lhs.lhs_dest == dest_local))
7215 		// ":const var": lock the value, but not referenced variables
7216 		generate_LOCKCONST(cctx);
7217 
7218 	    if (is_decl
7219 		    && (lhs.lhs_type->tt_type == VAR_DICT
7220 					  || lhs.lhs_type->tt_type == VAR_LIST)
7221 		    && lhs.lhs_type->tt_member != NULL
7222 		    && !(lhs.lhs_type->tt_member == &t_any
7223 			    && oplen > 0
7224 			    && rhs_type != NULL
7225 			    && rhs_type->tt_type == lhs.lhs_type->tt_type
7226 			    && rhs_type->tt_member != &t_unknown)
7227 		    && lhs.lhs_type->tt_member != &t_unknown)
7228 		// Set the type in the list or dict, so that it can be checked,
7229 		// also in legacy script.  Not for "list<any> = val", then the
7230 		// type of "val" is used.
7231 		generate_SETTYPE(cctx, lhs.lhs_type);
7232 
7233 	    if (generate_store_lhs(cctx, &lhs, instr_count) == FAIL)
7234 	    {
7235 		cctx->ctx_lnum = save_lnum;
7236 		goto theend;
7237 	    }
7238 	}
7239 	cctx->ctx_lnum = save_lnum;
7240 
7241 	if (var_idx + 1 < var_count)
7242 	    var_start = skipwhite(lhs.lhs_dest_end + 1);
7243     }
7244 
7245     // For "[var, var] = expr" drop the "expr" value.
7246     // Also for "[var, var; _] = expr".
7247     if (var_count > 0 && (!semicolon || !did_generate_slice))
7248     {
7249 	if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
7250 	    goto theend;
7251     }
7252 
7253     ret = skipwhite(end);
7254 
7255 theend:
7256     vim_free(lhs.lhs_name);
7257     return ret;
7258 }
7259 
7260 /*
7261  * Check for an assignment at "eap->cmd", compile it if found.
7262  * Return NOTDONE if there is none, FAIL for failure, OK if done.
7263  */
7264     static int
7265 may_compile_assignment(exarg_T *eap, char_u **line, cctx_T *cctx)
7266 {
7267     char_u  *pskip;
7268     char_u  *p;
7269 
7270     // Assuming the command starts with a variable or function name,
7271     // find what follows.
7272     // Skip over "var.member", "var[idx]" and the like.
7273     // Also "&opt = val", "$ENV = val" and "@r = val".
7274     pskip = (*eap->cmd == '&' || *eap->cmd == '$' || *eap->cmd == '@')
7275 						 ? eap->cmd + 1 : eap->cmd;
7276     p = to_name_end(pskip, TRUE);
7277     if (p > eap->cmd && *p != NUL)
7278     {
7279 	char_u *var_end;
7280 	int	oplen;
7281 	int	heredoc;
7282 
7283 	if (eap->cmd[0] == '@')
7284 	    var_end = eap->cmd + 2;
7285 	else
7286 	    var_end = find_name_end(pskip, NULL, NULL,
7287 					FNE_CHECK_START | FNE_INCL_BR);
7288 	oplen = assignment_len(skipwhite(var_end), &heredoc);
7289 	if (oplen > 0)
7290 	{
7291 	    size_t len = p - eap->cmd;
7292 
7293 	    // Recognize an assignment if we recognize the variable
7294 	    // name:
7295 	    // "g:var = expr"
7296 	    // "local = expr"  where "local" is a local var.
7297 	    // "script = expr"  where "script" is a script-local var.
7298 	    // "import = expr"  where "import" is an imported var
7299 	    // "&opt = expr"
7300 	    // "$ENV = expr"
7301 	    // "@r = expr"
7302 	    if (*eap->cmd == '&'
7303 		    || *eap->cmd == '$'
7304 		    || *eap->cmd == '@'
7305 		    || ((len) > 2 && eap->cmd[1] == ':')
7306 		    || variable_exists(eap->cmd, len, cctx))
7307 	    {
7308 		*line = compile_assignment(eap->cmd, eap, CMD_SIZE, cctx);
7309 		if (*line == NULL || *line == eap->cmd)
7310 		    return FAIL;
7311 		return OK;
7312 	    }
7313 	}
7314     }
7315 
7316     if (*eap->cmd == '[')
7317     {
7318 	// [var, var] = expr
7319 	*line = compile_assignment(eap->cmd, eap, CMD_SIZE, cctx);
7320 	if (*line == NULL)
7321 	    return FAIL;
7322 	if (*line != eap->cmd)
7323 	    return OK;
7324     }
7325     return NOTDONE;
7326 }
7327 
7328 /*
7329  * Check if "name" can be "unlet".
7330  */
7331     int
7332 check_vim9_unlet(char_u *name)
7333 {
7334     if (name[1] != ':' || vim_strchr((char_u *)"gwtb", *name) == NULL)
7335     {
7336 	// "unlet s:var" is allowed in legacy script.
7337 	if (*name == 's' && !script_is_vim9())
7338 	    return OK;
7339 	semsg(_(e_cannot_unlet_str), name);
7340 	return FAIL;
7341     }
7342     return OK;
7343 }
7344 
7345 /*
7346  * Callback passed to ex_unletlock().
7347  */
7348     static int
7349 compile_unlet(
7350     lval_T  *lvp,
7351     char_u  *name_end,
7352     exarg_T *eap,
7353     int	    deep UNUSED,
7354     void    *coookie)
7355 {
7356     cctx_T	*cctx = coookie;
7357     char_u	*p = lvp->ll_name;
7358     int		cc = *name_end;
7359     int		ret = OK;
7360 
7361     if (cctx->ctx_skip == SKIP_YES)
7362 	return OK;
7363 
7364     *name_end = NUL;
7365     if (*p == '$')
7366     {
7367 	// :unlet $ENV_VAR
7368 	ret = generate_UNLET(cctx, ISN_UNLETENV, p + 1, eap->forceit);
7369     }
7370     else if (vim_strchr(p, '.') != NULL || vim_strchr(p, '[') != NULL)
7371     {
7372 	lhs_T	    lhs;
7373 
7374 	// This is similar to assigning: lookup the list/dict, compile the
7375 	// idx/key.  Then instead of storing the value unlet the item.
7376 	// unlet {list}[idx]
7377 	// unlet {dict}[key]  dict.key
7378 	//
7379 	// Figure out the LHS type and other properties.
7380 	//
7381 	ret = compile_lhs(p, &lhs, CMD_unlet, FALSE, 0, cctx);
7382 
7383 	// : unlet an indexed item
7384 	if (!lhs.lhs_has_index)
7385 	{
7386 	    iemsg("called compile_lhs() without an index");
7387 	    ret = FAIL;
7388 	}
7389 	else
7390 	{
7391 	    // Use the info in "lhs" to unlet the item at the index in the
7392 	    // list or dict.
7393 	    ret = compile_assign_unlet(p, &lhs, FALSE, &t_void, cctx);
7394 	}
7395 
7396 	vim_free(lhs.lhs_name);
7397     }
7398     else if (check_vim9_unlet(p) == FAIL)
7399     {
7400 	ret = FAIL;
7401     }
7402     else
7403     {
7404 	// Normal name.  Only supports g:, w:, t: and b: namespaces.
7405 	ret = generate_UNLET(cctx, ISN_UNLET, p, eap->forceit);
7406     }
7407 
7408     *name_end = cc;
7409     return ret;
7410 }
7411 
7412 /*
7413  * Callback passed to ex_unletlock().
7414  */
7415     static int
7416 compile_lock_unlock(
7417     lval_T  *lvp,
7418     char_u  *name_end,
7419     exarg_T *eap,
7420     int	    deep UNUSED,
7421     void    *coookie)
7422 {
7423     cctx_T	*cctx = coookie;
7424     int		cc = *name_end;
7425     char_u	*p = lvp->ll_name;
7426     int		ret = OK;
7427     size_t	len;
7428     char_u	*buf;
7429 
7430     if (cctx->ctx_skip == SKIP_YES)
7431 	return OK;
7432 
7433     // Cannot use :lockvar and :unlockvar on local variables.
7434     if (p[1] != ':')
7435     {
7436 	char_u *end = find_name_end(p, NULL, NULL, FNE_CHECK_START);
7437 
7438 	if (lookup_local(p, end - p, NULL, cctx) == OK)
7439 	{
7440 	    emsg(_(e_cannot_lock_unlock_local_variable));
7441 	    return FAIL;
7442 	}
7443     }
7444 
7445     // Checking is done at runtime.
7446     *name_end = NUL;
7447     len = name_end - p + 20;
7448     buf = alloc(len);
7449     if (buf == NULL)
7450 	ret = FAIL;
7451     else
7452     {
7453 	vim_snprintf((char *)buf, len, "%s %s",
7454 		eap->cmdidx == CMD_lockvar ? "lockvar" : "unlockvar",
7455 		p);
7456 	ret = generate_EXEC(cctx, buf);
7457 
7458 	vim_free(buf);
7459 	*name_end = cc;
7460     }
7461     return ret;
7462 }
7463 
7464 /*
7465  * compile "unlet var", "lock var" and "unlock var"
7466  * "arg" points to "var".
7467  */
7468     static char_u *
7469 compile_unletlock(char_u *arg, exarg_T *eap, cctx_T *cctx)
7470 {
7471     ex_unletlock(eap, arg, 0, GLV_NO_AUTOLOAD | GLV_COMPILING,
7472 	    eap->cmdidx == CMD_unlet ? compile_unlet : compile_lock_unlock,
7473 	    cctx);
7474     return eap->nextcmd == NULL ? (char_u *)"" : eap->nextcmd;
7475 }
7476 
7477 /*
7478  * generate a jump to the ":endif"/":endfor"/":endwhile"/":finally"/":endtry".
7479  */
7480     static int
7481 compile_jump_to_end(endlabel_T **el, jumpwhen_T when, cctx_T *cctx)
7482 {
7483     garray_T	*instr = &cctx->ctx_instr;
7484     endlabel_T  *endlabel = ALLOC_CLEAR_ONE(endlabel_T);
7485 
7486     if (endlabel == NULL)
7487 	return FAIL;
7488     endlabel->el_next = *el;
7489     *el = endlabel;
7490     endlabel->el_end_label = instr->ga_len;
7491 
7492     generate_JUMP(cctx, when, 0);
7493     return OK;
7494 }
7495 
7496     static void
7497 compile_fill_jump_to_end(endlabel_T **el, int jump_where, cctx_T *cctx)
7498 {
7499     garray_T	*instr = &cctx->ctx_instr;
7500 
7501     while (*el != NULL)
7502     {
7503 	endlabel_T  *cur = (*el);
7504 	isn_T	    *isn;
7505 
7506 	isn = ((isn_T *)instr->ga_data) + cur->el_end_label;
7507 	isn->isn_arg.jump.jump_where = jump_where;
7508 	*el = cur->el_next;
7509 	vim_free(cur);
7510     }
7511 }
7512 
7513     static void
7514 compile_free_jump_to_end(endlabel_T **el)
7515 {
7516     while (*el != NULL)
7517     {
7518 	endlabel_T  *cur = (*el);
7519 
7520 	*el = cur->el_next;
7521 	vim_free(cur);
7522     }
7523 }
7524 
7525 /*
7526  * Create a new scope and set up the generic items.
7527  */
7528     static scope_T *
7529 new_scope(cctx_T *cctx, scopetype_T type)
7530 {
7531     scope_T *scope = ALLOC_CLEAR_ONE(scope_T);
7532 
7533     if (scope == NULL)
7534 	return NULL;
7535     scope->se_outer = cctx->ctx_scope;
7536     cctx->ctx_scope = scope;
7537     scope->se_type = type;
7538     scope->se_local_count = cctx->ctx_locals.ga_len;
7539     return scope;
7540 }
7541 
7542 /*
7543  * Free the current scope and go back to the outer scope.
7544  */
7545     static void
7546 drop_scope(cctx_T *cctx)
7547 {
7548     scope_T *scope = cctx->ctx_scope;
7549 
7550     if (scope == NULL)
7551     {
7552 	iemsg("calling drop_scope() without a scope");
7553 	return;
7554     }
7555     cctx->ctx_scope = scope->se_outer;
7556     switch (scope->se_type)
7557     {
7558 	case IF_SCOPE:
7559 	    compile_free_jump_to_end(&scope->se_u.se_if.is_end_label); break;
7560 	case FOR_SCOPE:
7561 	    compile_free_jump_to_end(&scope->se_u.se_for.fs_end_label); break;
7562 	case WHILE_SCOPE:
7563 	    compile_free_jump_to_end(&scope->se_u.se_while.ws_end_label); break;
7564 	case TRY_SCOPE:
7565 	    compile_free_jump_to_end(&scope->se_u.se_try.ts_end_label); break;
7566 	case NO_SCOPE:
7567 	case BLOCK_SCOPE:
7568 	    break;
7569     }
7570     vim_free(scope);
7571 }
7572 
7573 /*
7574  * compile "if expr"
7575  *
7576  * "if expr" Produces instructions:
7577  *	EVAL expr		Push result of "expr"
7578  *	JUMP_IF_FALSE end
7579  *	... body ...
7580  * end:
7581  *
7582  * "if expr | else" Produces instructions:
7583  *	EVAL expr		Push result of "expr"
7584  *	JUMP_IF_FALSE else
7585  *	... body ...
7586  *	JUMP_ALWAYS end
7587  * else:
7588  *	... body ...
7589  * end:
7590  *
7591  * "if expr1 | elseif expr2 | else" Produces instructions:
7592  *	EVAL expr		Push result of "expr"
7593  *	JUMP_IF_FALSE elseif
7594  *	... body ...
7595  *	JUMP_ALWAYS end
7596  * elseif:
7597  *	EVAL expr		Push result of "expr"
7598  *	JUMP_IF_FALSE else
7599  *	... body ...
7600  *	JUMP_ALWAYS end
7601  * else:
7602  *	... body ...
7603  * end:
7604  */
7605     static char_u *
7606 compile_if(char_u *arg, cctx_T *cctx)
7607 {
7608     char_u	*p = arg;
7609     garray_T	*instr = &cctx->ctx_instr;
7610     int		instr_count = instr->ga_len;
7611     scope_T	*scope;
7612     skip_T	skip_save = cctx->ctx_skip;
7613     ppconst_T	ppconst;
7614 
7615     CLEAR_FIELD(ppconst);
7616     if (compile_expr1(&p, cctx, &ppconst) == FAIL)
7617     {
7618 	clear_ppconst(&ppconst);
7619 	return NULL;
7620     }
7621     if (!ends_excmd2(arg, skipwhite(p)))
7622     {
7623 	semsg(_(e_trailing_arg), p);
7624 	return NULL;
7625     }
7626     if (cctx->ctx_skip == SKIP_YES)
7627 	clear_ppconst(&ppconst);
7628     else if (instr->ga_len == instr_count && ppconst.pp_used == 1)
7629     {
7630 	int error = FALSE;
7631 	int v;
7632 
7633 	// The expression results in a constant.
7634 	v = tv_get_bool_chk(&ppconst.pp_tv[0], &error);
7635 	clear_ppconst(&ppconst);
7636 	if (error)
7637 	    return NULL;
7638 	cctx->ctx_skip = v ? SKIP_NOT : SKIP_YES;
7639     }
7640     else
7641     {
7642 	// Not a constant, generate instructions for the expression.
7643 	cctx->ctx_skip = SKIP_UNKNOWN;
7644 	if (generate_ppconst(cctx, &ppconst) == FAIL)
7645 	    return NULL;
7646 	if (bool_on_stack(cctx) == FAIL)
7647 	    return NULL;
7648     }
7649 
7650     // CMDMOD_REV must come before the jump
7651     generate_undo_cmdmods(cctx);
7652 
7653     scope = new_scope(cctx, IF_SCOPE);
7654     if (scope == NULL)
7655 	return NULL;
7656     scope->se_skip_save = skip_save;
7657     // "is_had_return" will be reset if any block does not end in :return
7658     scope->se_u.se_if.is_had_return = TRUE;
7659 
7660     if (cctx->ctx_skip == SKIP_UNKNOWN)
7661     {
7662 	// "where" is set when ":elseif", "else" or ":endif" is found
7663 	scope->se_u.se_if.is_if_label = instr->ga_len;
7664 	generate_JUMP(cctx, JUMP_IF_FALSE, 0);
7665     }
7666     else
7667 	scope->se_u.se_if.is_if_label = -1;
7668 
7669 #ifdef FEAT_PROFILE
7670     if (cctx->ctx_compile_type == CT_PROFILE && cctx->ctx_skip == SKIP_YES
7671 						      && skip_save != SKIP_YES)
7672     {
7673 	// generated a profile start, need to generate a profile end, since it
7674 	// won't be done after returning
7675 	cctx->ctx_skip = SKIP_NOT;
7676 	generate_instr(cctx, ISN_PROF_END);
7677 	cctx->ctx_skip = SKIP_YES;
7678     }
7679 #endif
7680 
7681     return p;
7682 }
7683 
7684     static char_u *
7685 compile_elseif(char_u *arg, cctx_T *cctx)
7686 {
7687     char_u	*p = arg;
7688     garray_T	*instr = &cctx->ctx_instr;
7689     int		instr_count = instr->ga_len;
7690     isn_T	*isn;
7691     scope_T	*scope = cctx->ctx_scope;
7692     ppconst_T	ppconst;
7693     skip_T	save_skip = cctx->ctx_skip;
7694 
7695     if (scope == NULL || scope->se_type != IF_SCOPE)
7696     {
7697 	emsg(_(e_elseif_without_if));
7698 	return NULL;
7699     }
7700     unwind_locals(cctx, scope->se_local_count);
7701     if (!cctx->ctx_had_return)
7702 	scope->se_u.se_if.is_had_return = FALSE;
7703 
7704     if (cctx->ctx_skip == SKIP_NOT)
7705     {
7706 	// previous block was executed, this one and following will not
7707 	cctx->ctx_skip = SKIP_YES;
7708 	scope->se_u.se_if.is_seen_skip_not = TRUE;
7709     }
7710     if (scope->se_u.se_if.is_seen_skip_not)
7711     {
7712 	// A previous block was executed, skip over expression and bail out.
7713 	// Do not count the "elseif" for profiling and cmdmod
7714 	instr->ga_len = current_instr_idx(cctx);
7715 
7716 	skip_expr_cctx(&p, cctx);
7717 	return p;
7718     }
7719 
7720     if (cctx->ctx_skip == SKIP_UNKNOWN)
7721     {
7722 	int moved_cmdmod = FALSE;
7723 
7724 	// Move any CMDMOD instruction to after the jump
7725 	if (((isn_T *)instr->ga_data)[instr->ga_len - 1].isn_type == ISN_CMDMOD)
7726 	{
7727 	    if (GA_GROW_FAILS(instr, 1))
7728 		return NULL;
7729 	    ((isn_T *)instr->ga_data)[instr->ga_len] =
7730 				  ((isn_T *)instr->ga_data)[instr->ga_len - 1];
7731 	    --instr->ga_len;
7732 	    moved_cmdmod = TRUE;
7733 	}
7734 
7735 	if (compile_jump_to_end(&scope->se_u.se_if.is_end_label,
7736 						    JUMP_ALWAYS, cctx) == FAIL)
7737 	    return NULL;
7738 	// previous "if" or "elseif" jumps here
7739 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
7740 	isn->isn_arg.jump.jump_where = instr->ga_len;
7741 	if (moved_cmdmod)
7742 	    ++instr->ga_len;
7743     }
7744 
7745     // compile "expr"; if we know it evaluates to FALSE skip the block
7746     CLEAR_FIELD(ppconst);
7747     if (cctx->ctx_skip == SKIP_YES)
7748     {
7749 	cctx->ctx_skip = SKIP_UNKNOWN;
7750 #ifdef FEAT_PROFILE
7751 	if (cctx->ctx_compile_type == CT_PROFILE)
7752 	{
7753 	    // the previous block was skipped, need to profile this line
7754 	    generate_instr(cctx, ISN_PROF_START);
7755 	    instr_count = instr->ga_len;
7756 	}
7757 #endif
7758 	if (cctx->ctx_compile_type == CT_DEBUG)
7759 	{
7760 	    // the previous block was skipped, may want to debug this line
7761 	    generate_instr_debug(cctx);
7762 	    instr_count = instr->ga_len;
7763 	}
7764     }
7765     if (compile_expr1(&p, cctx, &ppconst) == FAIL)
7766     {
7767 	clear_ppconst(&ppconst);
7768 	return NULL;
7769     }
7770     cctx->ctx_skip = save_skip;
7771     if (!ends_excmd2(arg, skipwhite(p)))
7772     {
7773 	semsg(_(e_trailing_arg), p);
7774 	return NULL;
7775     }
7776     if (scope->se_skip_save == SKIP_YES)
7777 	clear_ppconst(&ppconst);
7778     else if (instr->ga_len == instr_count && ppconst.pp_used == 1)
7779     {
7780 	int error = FALSE;
7781 	int v;
7782 
7783 	// The expression results in a constant.
7784 	// TODO: how about nesting?
7785 	v = tv_get_bool_chk(&ppconst.pp_tv[0], &error);
7786 	if (error)
7787 	    return NULL;
7788 	cctx->ctx_skip = v ? SKIP_NOT : SKIP_YES;
7789 	clear_ppconst(&ppconst);
7790 	scope->se_u.se_if.is_if_label = -1;
7791     }
7792     else
7793     {
7794 	// Not a constant, generate instructions for the expression.
7795 	cctx->ctx_skip = SKIP_UNKNOWN;
7796 	if (generate_ppconst(cctx, &ppconst) == FAIL)
7797 	    return NULL;
7798 	if (bool_on_stack(cctx) == FAIL)
7799 	    return NULL;
7800 
7801 	// CMDMOD_REV must come before the jump
7802 	generate_undo_cmdmods(cctx);
7803 
7804 	// "where" is set when ":elseif", "else" or ":endif" is found
7805 	scope->se_u.se_if.is_if_label = instr->ga_len;
7806 	generate_JUMP(cctx, JUMP_IF_FALSE, 0);
7807     }
7808 
7809     return p;
7810 }
7811 
7812     static char_u *
7813 compile_else(char_u *arg, cctx_T *cctx)
7814 {
7815     char_u	*p = arg;
7816     garray_T	*instr = &cctx->ctx_instr;
7817     isn_T	*isn;
7818     scope_T	*scope = cctx->ctx_scope;
7819 
7820     if (scope == NULL || scope->se_type != IF_SCOPE)
7821     {
7822 	emsg(_(e_else_without_if));
7823 	return NULL;
7824     }
7825     unwind_locals(cctx, scope->se_local_count);
7826     if (!cctx->ctx_had_return)
7827 	scope->se_u.se_if.is_had_return = FALSE;
7828     scope->se_u.se_if.is_seen_else = TRUE;
7829 
7830 #ifdef FEAT_PROFILE
7831     if (cctx->ctx_compile_type == CT_PROFILE)
7832     {
7833 	if (cctx->ctx_skip == SKIP_NOT
7834 		&& ((isn_T *)instr->ga_data)[instr->ga_len - 1]
7835 						   .isn_type == ISN_PROF_START)
7836 	    // the previous block was executed, do not count "else" for
7837 	    // profiling
7838 	    --instr->ga_len;
7839 	if (cctx->ctx_skip == SKIP_YES && !scope->se_u.se_if.is_seen_skip_not)
7840 	{
7841 	    // the previous block was not executed, this one will, do count the
7842 	    // "else" for profiling
7843 	    cctx->ctx_skip = SKIP_NOT;
7844 	    generate_instr(cctx, ISN_PROF_END);
7845 	    generate_instr(cctx, ISN_PROF_START);
7846 	    cctx->ctx_skip = SKIP_YES;
7847 	}
7848     }
7849 #endif
7850 
7851     if (!scope->se_u.se_if.is_seen_skip_not && scope->se_skip_save != SKIP_YES)
7852     {
7853 	// jump from previous block to the end, unless the else block is empty
7854 	if (cctx->ctx_skip == SKIP_UNKNOWN)
7855 	{
7856 	    if (!cctx->ctx_had_return
7857 		    && compile_jump_to_end(&scope->se_u.se_if.is_end_label,
7858 						    JUMP_ALWAYS, cctx) == FAIL)
7859 		return NULL;
7860 	}
7861 
7862 	if (cctx->ctx_skip == SKIP_UNKNOWN)
7863 	{
7864 	    if (scope->se_u.se_if.is_if_label >= 0)
7865 	    {
7866 		// previous "if" or "elseif" jumps here
7867 		isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
7868 		isn->isn_arg.jump.jump_where = instr->ga_len;
7869 		scope->se_u.se_if.is_if_label = -1;
7870 	    }
7871 	}
7872 
7873 	if (cctx->ctx_skip != SKIP_UNKNOWN)
7874 	    cctx->ctx_skip = cctx->ctx_skip == SKIP_YES ? SKIP_NOT : SKIP_YES;
7875     }
7876 
7877     return p;
7878 }
7879 
7880     static char_u *
7881 compile_endif(char_u *arg, cctx_T *cctx)
7882 {
7883     scope_T	*scope = cctx->ctx_scope;
7884     ifscope_T	*ifscope;
7885     garray_T	*instr = &cctx->ctx_instr;
7886     isn_T	*isn;
7887 
7888     if (misplaced_cmdmod(cctx))
7889 	return NULL;
7890 
7891     if (scope == NULL || scope->se_type != IF_SCOPE)
7892     {
7893 	emsg(_(e_endif_without_if));
7894 	return NULL;
7895     }
7896     ifscope = &scope->se_u.se_if;
7897     unwind_locals(cctx, scope->se_local_count);
7898     if (!cctx->ctx_had_return)
7899 	ifscope->is_had_return = FALSE;
7900 
7901     if (scope->se_u.se_if.is_if_label >= 0)
7902     {
7903 	// previous "if" or "elseif" jumps here
7904 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
7905 	isn->isn_arg.jump.jump_where = instr->ga_len;
7906     }
7907     // Fill in the "end" label in jumps at the end of the blocks.
7908     compile_fill_jump_to_end(&ifscope->is_end_label, instr->ga_len, cctx);
7909 
7910 #ifdef FEAT_PROFILE
7911     // even when skipping we count the endif as executed, unless the block it's
7912     // in is skipped
7913     if (cctx->ctx_compile_type == CT_PROFILE && cctx->ctx_skip == SKIP_YES
7914 					    && scope->se_skip_save != SKIP_YES)
7915     {
7916 	cctx->ctx_skip = SKIP_NOT;
7917 	generate_instr(cctx, ISN_PROF_START);
7918     }
7919 #endif
7920     cctx->ctx_skip = scope->se_skip_save;
7921 
7922     // If all the blocks end in :return and there is an :else then the
7923     // had_return flag is set.
7924     cctx->ctx_had_return = ifscope->is_had_return && ifscope->is_seen_else;
7925 
7926     drop_scope(cctx);
7927     return arg;
7928 }
7929 
7930 /*
7931  * Compile "for var in expr":
7932  *
7933  * Produces instructions:
7934  *       PUSHNR -1
7935  *       STORE loop-idx		Set index to -1
7936  *       EVAL expr		result of "expr" on top of stack
7937  * top:  FOR loop-idx, end	Increment index, use list on bottom of stack
7938  *				- if beyond end, jump to "end"
7939  *				- otherwise get item from list and push it
7940  *       STORE var		Store item in "var"
7941  *       ... body ...
7942  *       JUMP top		Jump back to repeat
7943  * end:	 DROP			Drop the result of "expr"
7944  *
7945  * Compile "for [var1, var2] in expr" - as above, but instead of "STORE var":
7946  *	 UNPACK 2		Split item in 2
7947  *       STORE var1		Store item in "var1"
7948  *       STORE var2		Store item in "var2"
7949  */
7950     static char_u *
7951 compile_for(char_u *arg_start, cctx_T *cctx)
7952 {
7953     char_u	*arg;
7954     char_u	*arg_end;
7955     char_u	*name = NULL;
7956     char_u	*p;
7957     char_u	*wp;
7958     int		var_count = 0;
7959     int		var_list = FALSE;
7960     int		semicolon = FALSE;
7961     size_t	varlen;
7962     garray_T	*stack = &cctx->ctx_type_stack;
7963     garray_T	*instr = &cctx->ctx_instr;
7964     scope_T	*scope;
7965     lvar_T	*loop_lvar;	// loop iteration variable
7966     lvar_T	*var_lvar;	// variable for "var"
7967     type_T	*vartype;
7968     type_T	*item_type = &t_any;
7969     int		idx;
7970     int		prev_lnum = cctx->ctx_prev_lnum;
7971 
7972     p = skip_var_list(arg_start, TRUE, &var_count, &semicolon, FALSE);
7973     if (p == NULL)
7974 	return NULL;
7975     if (var_count == 0)
7976 	var_count = 1;
7977     else
7978 	var_list = TRUE;  // can also be a list of one variable
7979 
7980     // consume "in"
7981     wp = p;
7982     if (may_get_next_line_error(wp, &p, cctx) == FAIL)
7983 	return NULL;
7984     if (STRNCMP(p, "in", 2) != 0 || !IS_WHITE_OR_NUL(p[2]))
7985     {
7986 	if (*p == ':' && wp != p)
7987 	    semsg(_(e_no_white_space_allowed_before_colon_str), p);
7988 	else
7989 	    emsg(_(e_missing_in));
7990 	return NULL;
7991     }
7992     wp = p + 2;
7993     if (may_get_next_line_error(wp, &p, cctx) == FAIL)
7994 	return NULL;
7995 
7996     // Remove the already generated ISN_DEBUG, it is written below the ISN_FOR
7997     // instruction.
7998     if (cctx->ctx_compile_type == CT_DEBUG && instr->ga_len > 0
7999 	    && ((isn_T *)instr->ga_data)[instr->ga_len - 1]
8000 							.isn_type == ISN_DEBUG)
8001     {
8002 	--instr->ga_len;
8003 	prev_lnum = ((isn_T *)instr->ga_data)[instr->ga_len]
8004 						 .isn_arg.debug.dbg_break_lnum;
8005     }
8006 
8007     scope = new_scope(cctx, FOR_SCOPE);
8008     if (scope == NULL)
8009 	return NULL;
8010 
8011     // Reserve a variable to store the loop iteration counter and initialize it
8012     // to -1.
8013     loop_lvar = reserve_local(cctx, (char_u *)"", 0, FALSE, &t_number);
8014     if (loop_lvar == NULL)
8015     {
8016 	// out of memory
8017 	drop_scope(cctx);
8018 	return NULL;
8019     }
8020     generate_STORENR(cctx, loop_lvar->lv_idx, -1);
8021 
8022     // compile "expr", it remains on the stack until "endfor"
8023     arg = p;
8024     if (compile_expr0(&arg, cctx) == FAIL)
8025     {
8026 	drop_scope(cctx);
8027 	return NULL;
8028     }
8029     arg_end = arg;
8030 
8031     // If we know the type of "var" and it is a not a supported type we can
8032     // give an error now.
8033     vartype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
8034     if (vartype->tt_type != VAR_LIST && vartype->tt_type != VAR_STRING
8035 		&& vartype->tt_type != VAR_BLOB && vartype->tt_type != VAR_ANY)
8036     {
8037 	semsg(_(e_for_loop_on_str_not_supported),
8038 					       vartype_name(vartype->tt_type));
8039 	drop_scope(cctx);
8040 	return NULL;
8041     }
8042 
8043     if (vartype->tt_type == VAR_STRING)
8044 	item_type = &t_string;
8045     else if (vartype->tt_type == VAR_BLOB)
8046 	item_type = &t_number;
8047     else if (vartype->tt_type == VAR_LIST
8048 				     && vartype->tt_member->tt_type != VAR_ANY)
8049     {
8050 	if (!var_list)
8051 	    item_type = vartype->tt_member;
8052 	else if (vartype->tt_member->tt_type == VAR_LIST
8053 		      && vartype->tt_member->tt_member->tt_type != VAR_ANY)
8054 	    // TODO: should get the type for each lhs
8055 	    item_type = vartype->tt_member->tt_member;
8056     }
8057 
8058     // CMDMOD_REV must come before the FOR instruction.
8059     generate_undo_cmdmods(cctx);
8060 
8061     // "for_end" is set when ":endfor" is found
8062     scope->se_u.se_for.fs_top_label = current_instr_idx(cctx);
8063 
8064     generate_FOR(cctx, loop_lvar->lv_idx);
8065 
8066     arg = arg_start;
8067     if (var_list)
8068     {
8069 	generate_UNPACK(cctx, var_count, semicolon);
8070 	arg = skipwhite(arg + 1);	// skip white after '['
8071 
8072 	// the list item is replaced by a number of items
8073 	if (GA_GROW_FAILS(stack, var_count - 1))
8074 	{
8075 	    drop_scope(cctx);
8076 	    return NULL;
8077 	}
8078 	--stack->ga_len;
8079 	for (idx = 0; idx < var_count; ++idx)
8080 	{
8081 	    ((type_T **)stack->ga_data)[stack->ga_len] =
8082 				(semicolon && idx == 0) ? vartype : item_type;
8083 	    ++stack->ga_len;
8084 	}
8085     }
8086 
8087     for (idx = 0; idx < var_count; ++idx)
8088     {
8089 	assign_dest_T	dest = dest_local;
8090 	int		opt_flags = 0;
8091 	int		vimvaridx = -1;
8092 	type_T		*type = &t_any;
8093 	type_T		*lhs_type = &t_any;
8094 	where_T		where = WHERE_INIT;
8095 
8096 	p = skip_var_one(arg, FALSE);
8097 	varlen = p - arg;
8098 	name = vim_strnsave(arg, varlen);
8099 	if (name == NULL)
8100 	    goto failed;
8101 	if (*p == ':')
8102 	{
8103 	    p = skipwhite(p + 1);
8104 	    lhs_type = parse_type(&p, cctx->ctx_type_list, TRUE);
8105 	}
8106 
8107 	// TODO: script var not supported?
8108 	if (get_var_dest(name, &dest, CMD_for, &opt_flags,
8109 					      &vimvaridx, &type, cctx) == FAIL)
8110 	    goto failed;
8111 	if (dest != dest_local)
8112 	{
8113 	    if (generate_store_var(cctx, dest, opt_flags, vimvaridx,
8114 						     0, 0, type, name) == FAIL)
8115 		goto failed;
8116 	}
8117 	else if (varlen == 1 && *arg == '_')
8118 	{
8119 	    // Assigning to "_": drop the value.
8120 	    if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
8121 		goto failed;
8122 	}
8123 	else
8124 	{
8125 	    if (lookup_local(arg, varlen, NULL, cctx) == OK)
8126 	    {
8127 		semsg(_(e_variable_already_declared), arg);
8128 		goto failed;
8129 	    }
8130 
8131 	    if (STRNCMP(name, "s:", 2) == 0)
8132 	    {
8133 		semsg(_(e_cannot_declare_script_variable_in_function), name);
8134 		goto failed;
8135 	    }
8136 
8137 	    // Reserve a variable to store "var".
8138 	    where.wt_index = var_list ? idx + 1 : 0;
8139 	    where.wt_variable = TRUE;
8140 	    if (lhs_type == &t_any)
8141 		lhs_type = item_type;
8142 	    else if (item_type != &t_unknown
8143 			&& (item_type == &t_any
8144 			  ? need_type(item_type, lhs_type,
8145 						     -1, 0, cctx, FALSE, FALSE)
8146 			  : check_type(lhs_type, item_type, TRUE, where))
8147 			== FAIL)
8148 		goto failed;
8149 	    var_lvar = reserve_local(cctx, arg, varlen, TRUE, lhs_type);
8150 	    if (var_lvar == NULL)
8151 		// out of memory or used as an argument
8152 		goto failed;
8153 
8154 	    if (semicolon && idx == var_count - 1)
8155 		var_lvar->lv_type = vartype;
8156 	    else
8157 		var_lvar->lv_type = item_type;
8158 	    generate_STORE(cctx, ISN_STORE, var_lvar->lv_idx, NULL);
8159 	}
8160 
8161 	if (*p == ',' || *p == ';')
8162 	    ++p;
8163 	arg = skipwhite(p);
8164 	vim_free(name);
8165     }
8166 
8167     if (cctx->ctx_compile_type == CT_DEBUG)
8168     {
8169 	int save_prev_lnum = cctx->ctx_prev_lnum;
8170 
8171 	// Add ISN_DEBUG here, so that the loop variables can be inspected.
8172 	// Use the prev_lnum from the ISN_DEBUG instruction removed above.
8173 	cctx->ctx_prev_lnum = prev_lnum;
8174 	generate_instr_debug(cctx);
8175 	cctx->ctx_prev_lnum = save_prev_lnum;
8176     }
8177 
8178     return arg_end;
8179 
8180 failed:
8181     vim_free(name);
8182     drop_scope(cctx);
8183     return NULL;
8184 }
8185 
8186 /*
8187  * compile "endfor"
8188  */
8189     static char_u *
8190 compile_endfor(char_u *arg, cctx_T *cctx)
8191 {
8192     garray_T	*instr = &cctx->ctx_instr;
8193     scope_T	*scope = cctx->ctx_scope;
8194     forscope_T	*forscope;
8195     isn_T	*isn;
8196 
8197     if (misplaced_cmdmod(cctx))
8198 	return NULL;
8199 
8200     if (scope == NULL || scope->se_type != FOR_SCOPE)
8201     {
8202 	emsg(_(e_for));
8203 	return NULL;
8204     }
8205     forscope = &scope->se_u.se_for;
8206     cctx->ctx_scope = scope->se_outer;
8207     unwind_locals(cctx, scope->se_local_count);
8208 
8209     // At end of ":for" scope jump back to the FOR instruction.
8210     generate_JUMP(cctx, JUMP_ALWAYS, forscope->fs_top_label);
8211 
8212     // Fill in the "end" label in the FOR statement so it can jump here.
8213     isn = ((isn_T *)instr->ga_data) + forscope->fs_top_label;
8214     isn->isn_arg.forloop.for_end = instr->ga_len;
8215 
8216     // Fill in the "end" label any BREAK statements
8217     compile_fill_jump_to_end(&forscope->fs_end_label, instr->ga_len, cctx);
8218 
8219     // Below the ":for" scope drop the "expr" list from the stack.
8220     if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
8221 	return NULL;
8222 
8223     vim_free(scope);
8224 
8225     return arg;
8226 }
8227 
8228 /*
8229  * compile "while expr"
8230  *
8231  * Produces instructions:
8232  * top:  EVAL expr		Push result of "expr"
8233  *       JUMP_IF_FALSE end	jump if false
8234  *       ... body ...
8235  *       JUMP top		Jump back to repeat
8236  * end:
8237  *
8238  */
8239     static char_u *
8240 compile_while(char_u *arg, cctx_T *cctx)
8241 {
8242     char_u	*p = arg;
8243     scope_T	*scope;
8244 
8245     scope = new_scope(cctx, WHILE_SCOPE);
8246     if (scope == NULL)
8247 	return NULL;
8248 
8249     // "endwhile" jumps back here, one before when profiling or using cmdmods
8250     scope->se_u.se_while.ws_top_label = current_instr_idx(cctx);
8251 
8252     // compile "expr"
8253     if (compile_expr0(&p, cctx) == FAIL)
8254 	return NULL;
8255     if (!ends_excmd2(arg, skipwhite(p)))
8256     {
8257 	semsg(_(e_trailing_arg), p);
8258 	return NULL;
8259     }
8260 
8261     if (bool_on_stack(cctx) == FAIL)
8262 	return FAIL;
8263 
8264     // CMDMOD_REV must come before the jump
8265     generate_undo_cmdmods(cctx);
8266 
8267     // "while_end" is set when ":endwhile" is found
8268     if (compile_jump_to_end(&scope->se_u.se_while.ws_end_label,
8269 						  JUMP_IF_FALSE, cctx) == FAIL)
8270 	return FAIL;
8271 
8272     return p;
8273 }
8274 
8275 /*
8276  * compile "endwhile"
8277  */
8278     static char_u *
8279 compile_endwhile(char_u *arg, cctx_T *cctx)
8280 {
8281     scope_T	*scope = cctx->ctx_scope;
8282     garray_T	*instr = &cctx->ctx_instr;
8283 
8284     if (misplaced_cmdmod(cctx))
8285 	return NULL;
8286     if (scope == NULL || scope->se_type != WHILE_SCOPE)
8287     {
8288 	emsg(_(e_while));
8289 	return NULL;
8290     }
8291     cctx->ctx_scope = scope->se_outer;
8292     unwind_locals(cctx, scope->se_local_count);
8293 
8294 #ifdef FEAT_PROFILE
8295     // count the endwhile before jumping
8296     may_generate_prof_end(cctx, cctx->ctx_lnum);
8297 #endif
8298 
8299     // At end of ":for" scope jump back to the FOR instruction.
8300     generate_JUMP(cctx, JUMP_ALWAYS, scope->se_u.se_while.ws_top_label);
8301 
8302     // Fill in the "end" label in the WHILE statement so it can jump here.
8303     // And in any jumps for ":break"
8304     compile_fill_jump_to_end(&scope->se_u.se_while.ws_end_label,
8305 							  instr->ga_len, cctx);
8306 
8307     vim_free(scope);
8308 
8309     return arg;
8310 }
8311 
8312 /*
8313  * compile "continue"
8314  */
8315     static char_u *
8316 compile_continue(char_u *arg, cctx_T *cctx)
8317 {
8318     scope_T	*scope = cctx->ctx_scope;
8319     int		try_scopes = 0;
8320     int		loop_label;
8321 
8322     for (;;)
8323     {
8324 	if (scope == NULL)
8325 	{
8326 	    emsg(_(e_continue));
8327 	    return NULL;
8328 	}
8329 	if (scope->se_type == FOR_SCOPE)
8330 	{
8331 	    loop_label = scope->se_u.se_for.fs_top_label;
8332 	    break;
8333 	}
8334 	if (scope->se_type == WHILE_SCOPE)
8335 	{
8336 	    loop_label = scope->se_u.se_while.ws_top_label;
8337 	    break;
8338 	}
8339 	if (scope->se_type == TRY_SCOPE)
8340 	    ++try_scopes;
8341 	scope = scope->se_outer;
8342     }
8343 
8344     if (try_scopes > 0)
8345 	// Inside one or more try/catch blocks we first need to jump to the
8346 	// "finally" or "endtry" to cleanup.
8347 	generate_TRYCONT(cctx, try_scopes, loop_label);
8348     else
8349 	// Jump back to the FOR or WHILE instruction.
8350 	generate_JUMP(cctx, JUMP_ALWAYS, loop_label);
8351 
8352     return arg;
8353 }
8354 
8355 /*
8356  * compile "break"
8357  */
8358     static char_u *
8359 compile_break(char_u *arg, cctx_T *cctx)
8360 {
8361     scope_T	*scope = cctx->ctx_scope;
8362     endlabel_T	**el;
8363 
8364     for (;;)
8365     {
8366 	if (scope == NULL)
8367 	{
8368 	    emsg(_(e_break));
8369 	    return NULL;
8370 	}
8371 	if (scope->se_type == FOR_SCOPE || scope->se_type == WHILE_SCOPE)
8372 	    break;
8373 	scope = scope->se_outer;
8374     }
8375 
8376     // Jump to the end of the FOR or WHILE loop.
8377     if (scope->se_type == FOR_SCOPE)
8378 	el = &scope->se_u.se_for.fs_end_label;
8379     else
8380 	el = &scope->se_u.se_while.ws_end_label;
8381     if (compile_jump_to_end(el, JUMP_ALWAYS, cctx) == FAIL)
8382 	return FAIL;
8383 
8384     return arg;
8385 }
8386 
8387 /*
8388  * compile "{" start of block
8389  */
8390     static char_u *
8391 compile_block(char_u *arg, cctx_T *cctx)
8392 {
8393     if (new_scope(cctx, BLOCK_SCOPE) == NULL)
8394 	return NULL;
8395     return skipwhite(arg + 1);
8396 }
8397 
8398 /*
8399  * compile end of block: drop one scope
8400  */
8401     static void
8402 compile_endblock(cctx_T *cctx)
8403 {
8404     scope_T	*scope = cctx->ctx_scope;
8405 
8406     cctx->ctx_scope = scope->se_outer;
8407     unwind_locals(cctx, scope->se_local_count);
8408     vim_free(scope);
8409 }
8410 
8411 /*
8412  * compile "try"
8413  * Creates a new scope for the try-endtry, pointing to the first catch and
8414  * finally.
8415  * Creates another scope for the "try" block itself.
8416  * TRY instruction sets up exception handling at runtime.
8417  *
8418  *	"try"
8419  *	    TRY -> catch1, -> finally  push trystack entry
8420  *	    ... try block
8421  *	"throw {exception}"
8422  *	    EVAL {exception}
8423  *	    THROW		create exception
8424  *	    ... try block
8425  *	" catch {expr}"
8426  *	    JUMP -> finally
8427  * catch1:  PUSH exception
8428  *	    EVAL {expr}
8429  *	    MATCH
8430  *	    JUMP nomatch -> catch2
8431  *	    CATCH   remove exception
8432  *	    ... catch block
8433  *	" catch"
8434  *	    JUMP -> finally
8435  * catch2:  CATCH   remove exception
8436  *	    ... catch block
8437  *	" finally"
8438  * finally:
8439  *	    ... finally block
8440  *	" endtry"
8441  *	    ENDTRY  pop trystack entry, may rethrow
8442  */
8443     static char_u *
8444 compile_try(char_u *arg, cctx_T *cctx)
8445 {
8446     garray_T	*instr = &cctx->ctx_instr;
8447     scope_T	*try_scope;
8448     scope_T	*scope;
8449 
8450     if (misplaced_cmdmod(cctx))
8451 	return NULL;
8452 
8453     // scope that holds the jumps that go to catch/finally/endtry
8454     try_scope = new_scope(cctx, TRY_SCOPE);
8455     if (try_scope == NULL)
8456 	return NULL;
8457 
8458     if (cctx->ctx_skip != SKIP_YES)
8459     {
8460 	isn_T	*isn;
8461 
8462 	// "try_catch" is set when the first ":catch" is found or when no catch
8463 	// is found and ":finally" is found.
8464 	// "try_finally" is set when ":finally" is found
8465 	// "try_endtry" is set when ":endtry" is found
8466 	try_scope->se_u.se_try.ts_try_label = instr->ga_len;
8467 	if ((isn = generate_instr(cctx, ISN_TRY)) == NULL)
8468 	    return NULL;
8469 	isn->isn_arg.try.try_ref = ALLOC_CLEAR_ONE(tryref_T);
8470 	if (isn->isn_arg.try.try_ref == NULL)
8471 	    return NULL;
8472     }
8473 
8474     // scope for the try block itself
8475     scope = new_scope(cctx, BLOCK_SCOPE);
8476     if (scope == NULL)
8477 	return NULL;
8478 
8479     return arg;
8480 }
8481 
8482 /*
8483  * compile "catch {expr}"
8484  */
8485     static char_u *
8486 compile_catch(char_u *arg, cctx_T *cctx UNUSED)
8487 {
8488     scope_T	*scope = cctx->ctx_scope;
8489     garray_T	*instr = &cctx->ctx_instr;
8490     char_u	*p;
8491     isn_T	*isn;
8492 
8493     if (misplaced_cmdmod(cctx))
8494 	return NULL;
8495 
8496     // end block scope from :try or :catch
8497     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
8498 	compile_endblock(cctx);
8499     scope = cctx->ctx_scope;
8500 
8501     // Error if not in a :try scope
8502     if (scope == NULL || scope->se_type != TRY_SCOPE)
8503     {
8504 	emsg(_(e_catch));
8505 	return NULL;
8506     }
8507 
8508     if (scope->se_u.se_try.ts_caught_all)
8509     {
8510 	emsg(_(e_catch_unreachable_after_catch_all));
8511 	return NULL;
8512     }
8513 
8514     if (cctx->ctx_skip != SKIP_YES)
8515     {
8516 #ifdef FEAT_PROFILE
8517 	// the profile-start should be after the jump
8518 	if (cctx->ctx_compile_type == CT_PROFILE
8519 		&& instr->ga_len > 0
8520 		&& ((isn_T *)instr->ga_data)[instr->ga_len - 1]
8521 						   .isn_type == ISN_PROF_START)
8522 	    --instr->ga_len;
8523 #endif
8524 	// Jump from end of previous block to :finally or :endtry
8525 	if (compile_jump_to_end(&scope->se_u.se_try.ts_end_label,
8526 						    JUMP_ALWAYS, cctx) == FAIL)
8527 	    return NULL;
8528 
8529 	// End :try or :catch scope: set value in ISN_TRY instruction
8530 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
8531 	if (isn->isn_arg.try.try_ref->try_catch == 0)
8532 	    isn->isn_arg.try.try_ref->try_catch = instr->ga_len;
8533 	if (scope->se_u.se_try.ts_catch_label != 0)
8534 	{
8535 	    // Previous catch without match jumps here
8536 	    isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_catch_label;
8537 	    isn->isn_arg.jump.jump_where = instr->ga_len;
8538 	}
8539 #ifdef FEAT_PROFILE
8540 	if (cctx->ctx_compile_type == CT_PROFILE)
8541 	{
8542 	    // a "throw" that jumps here needs to be counted
8543 	    generate_instr(cctx, ISN_PROF_END);
8544 	    // the "catch" is also counted
8545 	    generate_instr(cctx, ISN_PROF_START);
8546 	}
8547 #endif
8548 	if (cctx->ctx_compile_type == CT_DEBUG)
8549 	    generate_instr_debug(cctx);
8550     }
8551 
8552     p = skipwhite(arg);
8553     if (ends_excmd2(arg, p))
8554     {
8555 	scope->se_u.se_try.ts_caught_all = TRUE;
8556 	scope->se_u.se_try.ts_catch_label = 0;
8557     }
8558     else
8559     {
8560 	char_u *end;
8561 	char_u *pat;
8562 	char_u *tofree = NULL;
8563 	int	dropped = 0;
8564 	int	len;
8565 
8566 	// Push v:exception, push {expr} and MATCH
8567 	generate_instr_type(cctx, ISN_PUSHEXC, &t_string);
8568 
8569 	end = skip_regexp_ex(p + 1, *p, TRUE, &tofree, &dropped, NULL);
8570 	if (*end != *p)
8571 	{
8572 	    semsg(_(e_separator_mismatch_str), p);
8573 	    vim_free(tofree);
8574 	    return FAIL;
8575 	}
8576 	if (tofree == NULL)
8577 	    len = (int)(end - (p + 1));
8578 	else
8579 	    len = (int)(end - tofree);
8580 	pat = vim_strnsave(tofree == NULL ? p + 1 : tofree, len);
8581 	vim_free(tofree);
8582 	p += len + 2 + dropped;
8583 	if (pat == NULL)
8584 	    return FAIL;
8585 	if (generate_PUSHS(cctx, &pat) == FAIL)
8586 	    return FAIL;
8587 
8588 	if (generate_COMPARE(cctx, EXPR_MATCH, FALSE) == FAIL)
8589 	    return NULL;
8590 
8591 	scope->se_u.se_try.ts_catch_label = instr->ga_len;
8592 	if (generate_JUMP(cctx, JUMP_IF_FALSE, 0) == FAIL)
8593 	    return NULL;
8594     }
8595 
8596     if (cctx->ctx_skip != SKIP_YES && generate_instr(cctx, ISN_CATCH) == NULL)
8597 	return NULL;
8598 
8599     if (new_scope(cctx, BLOCK_SCOPE) == NULL)
8600 	return NULL;
8601     return p;
8602 }
8603 
8604     static char_u *
8605 compile_finally(char_u *arg, cctx_T *cctx)
8606 {
8607     scope_T	*scope = cctx->ctx_scope;
8608     garray_T	*instr = &cctx->ctx_instr;
8609     isn_T	*isn;
8610     int		this_instr;
8611 
8612     if (misplaced_cmdmod(cctx))
8613 	return NULL;
8614 
8615     // end block scope from :try or :catch
8616     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
8617 	compile_endblock(cctx);
8618     scope = cctx->ctx_scope;
8619 
8620     // Error if not in a :try scope
8621     if (scope == NULL || scope->se_type != TRY_SCOPE)
8622     {
8623 	emsg(_(e_finally));
8624 	return NULL;
8625     }
8626 
8627     if (cctx->ctx_skip != SKIP_YES)
8628     {
8629 	// End :catch or :finally scope: set value in ISN_TRY instruction
8630 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
8631 	if (isn->isn_arg.try.try_ref->try_finally != 0)
8632 	{
8633 	    emsg(_(e_finally_dup));
8634 	    return NULL;
8635 	}
8636 
8637 	this_instr = instr->ga_len;
8638 #ifdef FEAT_PROFILE
8639 	if (cctx->ctx_compile_type == CT_PROFILE
8640 		&& ((isn_T *)instr->ga_data)[this_instr - 1]
8641 						       .isn_type == ISN_PROF_START)
8642 	{
8643 	    // jump to the profile start of the "finally"
8644 	    --this_instr;
8645 
8646 	    // jump to the profile end above it
8647 	    if (this_instr > 0 && ((isn_T *)instr->ga_data)[this_instr - 1]
8648 							 .isn_type == ISN_PROF_END)
8649 		--this_instr;
8650 	}
8651 #endif
8652 
8653 	// Fill in the "end" label in jumps at the end of the blocks.
8654 	compile_fill_jump_to_end(&scope->se_u.se_try.ts_end_label,
8655 								this_instr, cctx);
8656 
8657 	// If there is no :catch then an exception jumps to :finally.
8658 	if (isn->isn_arg.try.try_ref->try_catch == 0)
8659 	    isn->isn_arg.try.try_ref->try_catch = this_instr;
8660 	isn->isn_arg.try.try_ref->try_finally = this_instr;
8661 	if (scope->se_u.se_try.ts_catch_label != 0)
8662 	{
8663 	    // Previous catch without match jumps here
8664 	    isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_catch_label;
8665 	    isn->isn_arg.jump.jump_where = this_instr;
8666 	    scope->se_u.se_try.ts_catch_label = 0;
8667 	}
8668 	if (generate_instr(cctx, ISN_FINALLY) == NULL)
8669 	    return NULL;
8670 
8671 	// TODO: set index in ts_finally_label jumps
8672     }
8673 
8674     return arg;
8675 }
8676 
8677     static char_u *
8678 compile_endtry(char_u *arg, cctx_T *cctx)
8679 {
8680     scope_T	*scope = cctx->ctx_scope;
8681     garray_T	*instr = &cctx->ctx_instr;
8682     isn_T	*try_isn;
8683 
8684     if (misplaced_cmdmod(cctx))
8685 	return NULL;
8686 
8687     // end block scope from :catch or :finally
8688     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
8689 	compile_endblock(cctx);
8690     scope = cctx->ctx_scope;
8691 
8692     // Error if not in a :try scope
8693     if (scope == NULL || scope->se_type != TRY_SCOPE)
8694     {
8695 	if (scope == NULL)
8696 	    emsg(_(e_no_endtry));
8697 	else if (scope->se_type == WHILE_SCOPE)
8698 	    emsg(_(e_endwhile));
8699 	else if (scope->se_type == FOR_SCOPE)
8700 	    emsg(_(e_endfor));
8701 	else
8702 	    emsg(_(e_endif));
8703 	return NULL;
8704     }
8705 
8706     try_isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
8707     if (cctx->ctx_skip != SKIP_YES)
8708     {
8709 	if (try_isn->isn_arg.try.try_ref->try_catch == 0
8710 				      && try_isn->isn_arg.try.try_ref->try_finally == 0)
8711 	{
8712 	    emsg(_(e_missing_catch_or_finally));
8713 	    return NULL;
8714 	}
8715 
8716 #ifdef FEAT_PROFILE
8717 	if (cctx->ctx_compile_type == CT_PROFILE
8718 		&& ((isn_T *)instr->ga_data)[instr->ga_len - 1]
8719 						.isn_type == ISN_PROF_START)
8720 	    // move the profile start after "endtry" so that it's not counted when
8721 	    // the exception is rethrown.
8722 	    --instr->ga_len;
8723 #endif
8724 
8725 	// Fill in the "end" label in jumps at the end of the blocks, if not
8726 	// done by ":finally".
8727 	compile_fill_jump_to_end(&scope->se_u.se_try.ts_end_label,
8728 							  instr->ga_len, cctx);
8729 
8730 	if (scope->se_u.se_try.ts_catch_label != 0)
8731 	{
8732 	    // Last catch without match jumps here
8733 	    isn_T *isn = ((isn_T *)instr->ga_data)
8734 					   + scope->se_u.se_try.ts_catch_label;
8735 	    isn->isn_arg.jump.jump_where = instr->ga_len;
8736 	}
8737     }
8738 
8739     compile_endblock(cctx);
8740 
8741     if (cctx->ctx_skip != SKIP_YES)
8742     {
8743 	// End :catch or :finally scope: set instruction index in ISN_TRY
8744 	// instruction
8745 	try_isn->isn_arg.try.try_ref->try_endtry = instr->ga_len;
8746 	if (cctx->ctx_skip != SKIP_YES
8747 				   && generate_instr(cctx, ISN_ENDTRY) == NULL)
8748 	    return NULL;
8749 #ifdef FEAT_PROFILE
8750 	if (cctx->ctx_compile_type == CT_PROFILE)
8751 	    generate_instr(cctx, ISN_PROF_START);
8752 #endif
8753     }
8754     return arg;
8755 }
8756 
8757 /*
8758  * compile "throw {expr}"
8759  */
8760     static char_u *
8761 compile_throw(char_u *arg, cctx_T *cctx UNUSED)
8762 {
8763     char_u *p = skipwhite(arg);
8764 
8765     if (compile_expr0(&p, cctx) == FAIL)
8766 	return NULL;
8767     if (cctx->ctx_skip == SKIP_YES)
8768 	return p;
8769     if (may_generate_2STRING(-1, FALSE, cctx) == FAIL)
8770 	return NULL;
8771     if (generate_instr_drop(cctx, ISN_THROW, 1) == NULL)
8772 	return NULL;
8773 
8774     return p;
8775 }
8776 
8777     static char_u *
8778 compile_eval(char_u *arg, cctx_T *cctx)
8779 {
8780     char_u	*p = arg;
8781     int		name_only;
8782     char_u	*alias;
8783     long	lnum = SOURCING_LNUM;
8784 
8785     // find_ex_command() will consider a variable name an expression, assuming
8786     // that something follows on the next line.  Check that something actually
8787     // follows, otherwise it's probably a misplaced command.
8788     get_name_len(&p, &alias, FALSE, FALSE);
8789     name_only = ends_excmd2(arg, skipwhite(p));
8790     vim_free(alias);
8791 
8792     p = arg;
8793     if (compile_expr0(&p, cctx) == FAIL)
8794 	return NULL;
8795 
8796     if (name_only && lnum == SOURCING_LNUM)
8797     {
8798 	semsg(_(e_expression_without_effect_str), arg);
8799 	return NULL;
8800     }
8801 
8802     // drop the result
8803     generate_instr_drop(cctx, ISN_DROP, 1);
8804 
8805     return skipwhite(p);
8806 }
8807 
8808 /*
8809  * compile "echo expr"
8810  * compile "echomsg expr"
8811  * compile "echoerr expr"
8812  * compile "echoconsole expr"
8813  * compile "execute expr"
8814  */
8815     static char_u *
8816 compile_mult_expr(char_u *arg, int cmdidx, cctx_T *cctx)
8817 {
8818     char_u	*p = arg;
8819     char_u	*prev = arg;
8820     char_u	*expr_start;
8821     int		count = 0;
8822     int		start_ctx_lnum = cctx->ctx_lnum;
8823     garray_T	*stack = &cctx->ctx_type_stack;
8824     type_T	*type;
8825 
8826     for (;;)
8827     {
8828 	if (ends_excmd2(prev, p))
8829 	    break;
8830 	expr_start = p;
8831 	if (compile_expr0(&p, cctx) == FAIL)
8832 	    return NULL;
8833 
8834 	if (cctx->ctx_skip != SKIP_YES)
8835 	{
8836 	    // check for non-void type
8837 	    type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
8838 	    if (type->tt_type == VAR_VOID)
8839 	    {
8840 		semsg(_(e_expression_does_not_result_in_value_str), expr_start);
8841 		return NULL;
8842 	    }
8843 	}
8844 
8845 	++count;
8846 	prev = p;
8847 	p = skipwhite(p);
8848     }
8849 
8850     if (count > 0)
8851     {
8852 	long save_lnum = cctx->ctx_lnum;
8853 
8854 	// Use the line number where the command started.
8855 	cctx->ctx_lnum = start_ctx_lnum;
8856 
8857 	if (cmdidx == CMD_echo || cmdidx == CMD_echon)
8858 	    generate_ECHO(cctx, cmdidx == CMD_echo, count);
8859 	else if (cmdidx == CMD_execute)
8860 	    generate_MULT_EXPR(cctx, ISN_EXECUTE, count);
8861 	else if (cmdidx == CMD_echomsg)
8862 	    generate_MULT_EXPR(cctx, ISN_ECHOMSG, count);
8863 	else if (cmdidx == CMD_echoconsole)
8864 	    generate_MULT_EXPR(cctx, ISN_ECHOCONSOLE, count);
8865 	else
8866 	    generate_MULT_EXPR(cctx, ISN_ECHOERR, count);
8867 
8868 	cctx->ctx_lnum = save_lnum;
8869     }
8870     return p;
8871 }
8872 
8873 /*
8874  * If "eap" has a range that is not a constant generate an ISN_RANGE
8875  * instruction to compute it and return OK.
8876  * Otherwise return FAIL, the caller must deal with any range.
8877  */
8878     static int
8879 compile_variable_range(exarg_T *eap, cctx_T *cctx)
8880 {
8881     char_u *range_end = skip_range(eap->cmd, TRUE, NULL);
8882     char_u *p = skipdigits(eap->cmd);
8883 
8884     if (p == range_end)
8885 	return FAIL;
8886     return generate_RANGE(cctx, vim_strnsave(eap->cmd, range_end - eap->cmd));
8887 }
8888 
8889 /*
8890  * :put r
8891  * :put ={expr}
8892  */
8893     static char_u *
8894 compile_put(char_u *arg, exarg_T *eap, cctx_T *cctx)
8895 {
8896     char_u	*line = arg;
8897     linenr_T	lnum;
8898     char	*errormsg;
8899     int		above = eap->forceit;
8900 
8901     eap->regname = *line;
8902 
8903     if (eap->regname == '=')
8904     {
8905 	char_u *p = line + 1;
8906 
8907 	if (compile_expr0(&p, cctx) == FAIL)
8908 	    return NULL;
8909 	line = p;
8910     }
8911     else if (eap->regname != NUL)
8912 	++line;
8913 
8914     if (compile_variable_range(eap, cctx) == OK)
8915     {
8916 	lnum = above ? LNUM_VARIABLE_RANGE_ABOVE : LNUM_VARIABLE_RANGE;
8917     }
8918     else
8919     {
8920 	// Either no range or a number.
8921 	// "errormsg" will not be set because the range is ADDR_LINES.
8922 	if (parse_cmd_address(eap, &errormsg, FALSE) == FAIL)
8923 	    // cannot happen
8924 	    return NULL;
8925 	if (eap->addr_count == 0)
8926 	    lnum = -1;
8927 	else
8928 	    lnum = eap->line2;
8929 	if (above)
8930 	    --lnum;
8931     }
8932 
8933     generate_PUT(cctx, eap->regname, lnum);
8934     return line;
8935 }
8936 
8937 /*
8938  * A command that is not compiled, execute with legacy code.
8939  */
8940     static char_u *
8941 compile_exec(char_u *line_arg, exarg_T *eap, cctx_T *cctx)
8942 {
8943     char_u	*line = line_arg;
8944     char_u	*p;
8945     int		has_expr = FALSE;
8946     char_u	*nextcmd = (char_u *)"";
8947     char_u	*tofree = NULL;
8948 
8949     if (cctx->ctx_skip == SKIP_YES)
8950 	goto theend;
8951 
8952     // If there was a prececing command modifier, drop it and include it in the
8953     // EXEC command.
8954     if (cctx->ctx_has_cmdmod)
8955     {
8956 	garray_T	*instr = &cctx->ctx_instr;
8957 	isn_T		*isn = ((isn_T *)instr->ga_data) + instr->ga_len - 1;
8958 
8959 	if (isn->isn_type == ISN_CMDMOD)
8960 	{
8961 	    vim_regfree(isn->isn_arg.cmdmod.cf_cmdmod
8962 					       ->cmod_filter_regmatch.regprog);
8963 	    vim_free(isn->isn_arg.cmdmod.cf_cmdmod);
8964 	    --instr->ga_len;
8965 	    cctx->ctx_has_cmdmod = FALSE;
8966 	}
8967     }
8968 
8969     if (eap->cmdidx >= 0 && eap->cmdidx < CMD_SIZE)
8970     {
8971 	long	argt = eap->argt;
8972 	int	usefilter = FALSE;
8973 
8974 	has_expr = argt & (EX_XFILE | EX_EXPAND);
8975 
8976 	// If the command can be followed by a bar, find the bar and truncate
8977 	// it, so that the following command can be compiled.
8978 	// The '|' is overwritten with a NUL, it is put back below.
8979 	if ((eap->cmdidx == CMD_write || eap->cmdidx == CMD_read)
8980 							   && *eap->arg == '!')
8981 	    // :w !filter or :r !filter or :r! filter
8982 	    usefilter = TRUE;
8983 	if ((argt & EX_TRLBAR) && !usefilter)
8984 	{
8985 	    eap->argt = argt;
8986 	    separate_nextcmd(eap);
8987 	    if (eap->nextcmd != NULL)
8988 		nextcmd = eap->nextcmd;
8989 	}
8990 	else if (eap->cmdidx == CMD_wincmd)
8991 	{
8992 	    p = eap->arg;
8993 	    if (*p != NUL)
8994 		++p;
8995 	    if (*p == 'g' || *p == Ctrl_G)
8996 		++p;
8997 	    p = skipwhite(p);
8998 	    if (*p == '|')
8999 	    {
9000 		*p = NUL;
9001 		nextcmd = p + 1;
9002 	    }
9003 	}
9004 	else if (eap->cmdidx == CMD_command || eap->cmdidx == CMD_autocmd)
9005 	{
9006 	    // If there is a trailing '{' read lines until the '}'
9007 	    p = eap->arg + STRLEN(eap->arg) - 1;
9008 	    while (p > eap->arg && VIM_ISWHITE(*p))
9009 		--p;
9010 	    if (*p == '{')
9011 	    {
9012 		exarg_T ea;
9013 		int	flags;  // unused
9014 		int	start_lnum = SOURCING_LNUM;
9015 
9016 		CLEAR_FIELD(ea);
9017 		ea.arg = eap->arg;
9018 		fill_exarg_from_cctx(&ea, cctx);
9019 		(void)may_get_cmd_block(&ea, p, &tofree, &flags);
9020 		if (tofree != NULL)
9021 		{
9022 		    *p = NUL;
9023 		    line = concat_str(line, tofree);
9024 		    if (line == NULL)
9025 			goto theend;
9026 		    vim_free(tofree);
9027 		    tofree = line;
9028 		    SOURCING_LNUM = start_lnum;
9029 		}
9030 	    }
9031 	}
9032     }
9033 
9034     if (eap->cmdidx == CMD_syntax && STRNCMP(eap->arg, "include ", 8) == 0)
9035     {
9036 	// expand filename in "syntax include [@group] filename"
9037 	has_expr = TRUE;
9038 	eap->arg = skipwhite(eap->arg + 7);
9039 	if (*eap->arg == '@')
9040 	    eap->arg = skiptowhite(eap->arg);
9041     }
9042 
9043     if ((eap->cmdidx == CMD_global || eap->cmdidx == CMD_vglobal)
9044 						       && STRLEN(eap->arg) > 4)
9045     {
9046 	int delim = *eap->arg;
9047 
9048 	p = skip_regexp_ex(eap->arg + 1, delim, TRUE, NULL, NULL, NULL);
9049 	if (*p == delim)
9050 	{
9051 	    eap->arg = p + 1;
9052 	    has_expr = TRUE;
9053 	}
9054     }
9055 
9056     if (eap->cmdidx == CMD_folddoopen || eap->cmdidx == CMD_folddoclosed)
9057     {
9058 	// TODO: should only expand when appropriate for the command
9059 	eap->arg = skiptowhite(eap->arg);
9060 	has_expr = TRUE;
9061     }
9062 
9063     if (has_expr && (p = (char_u *)strstr((char *)eap->arg, "`=")) != NULL)
9064     {
9065 	int	count = 0;
9066 	char_u	*start = skipwhite(line);
9067 
9068 	// :cmd xxx`=expr1`yyy`=expr2`zzz
9069 	// PUSHS ":cmd xxx"
9070 	// eval expr1
9071 	// PUSHS "yyy"
9072 	// eval expr2
9073 	// PUSHS "zzz"
9074 	// EXECCONCAT 5
9075 	for (;;)
9076 	{
9077 	    if (p > start)
9078 	    {
9079 		char_u *val = vim_strnsave(start, p - start);
9080 
9081 		generate_PUSHS(cctx, &val);
9082 		++count;
9083 	    }
9084 	    p += 2;
9085 	    if (compile_expr0(&p, cctx) == FAIL)
9086 		return NULL;
9087 	    may_generate_2STRING(-1, TRUE, cctx);
9088 	    ++count;
9089 	    p = skipwhite(p);
9090 	    if (*p != '`')
9091 	    {
9092 		emsg(_(e_missing_backtick));
9093 		return NULL;
9094 	    }
9095 	    start = p + 1;
9096 
9097 	    p = (char_u *)strstr((char *)start, "`=");
9098 	    if (p == NULL)
9099 	    {
9100 		if (*skipwhite(start) != NUL)
9101 		{
9102 		    char_u *val = vim_strsave(start);
9103 
9104 		    generate_PUSHS(cctx, &val);
9105 		    ++count;
9106 		}
9107 		break;
9108 	    }
9109 	}
9110 	generate_EXECCONCAT(cctx, count);
9111     }
9112     else
9113 	generate_EXEC(cctx, line);
9114 
9115 theend:
9116     if (*nextcmd != NUL)
9117     {
9118 	// the parser expects a pointer to the bar, put it back
9119 	--nextcmd;
9120 	*nextcmd = '|';
9121     }
9122     vim_free(tofree);
9123 
9124     return nextcmd;
9125 }
9126 
9127 /*
9128  * A script command with heredoc, e.g.
9129  *	ruby << EOF
9130  *	   command
9131  *	EOF
9132  * Has been turned into one long line with NL characters by
9133  * get_function_body():
9134  *	ruby << EOF<NL>   command<NL>EOF
9135  */
9136     static char_u *
9137 compile_script(char_u *line, cctx_T *cctx)
9138 {
9139     if (cctx->ctx_skip != SKIP_YES)
9140     {
9141 	isn_T	*isn;
9142 
9143 	if ((isn = generate_instr(cctx, ISN_EXEC_SPLIT)) == NULL)
9144 	    return NULL;
9145 	isn->isn_arg.string = vim_strsave(line);
9146     }
9147     return (char_u *)"";
9148 }
9149 
9150 
9151 /*
9152  * :s/pat/repl/
9153  */
9154     static char_u *
9155 compile_substitute(char_u *arg, exarg_T *eap, cctx_T *cctx)
9156 {
9157     char_u  *cmd = eap->arg;
9158     char_u  *expr = (char_u *)strstr((char *)cmd, "\\=");
9159 
9160     if (expr != NULL)
9161     {
9162 	int delimiter = *cmd++;
9163 
9164 	// There is a \=expr, find it in the substitute part.
9165 	cmd = skip_regexp_ex(cmd, delimiter, magic_isset(), NULL, NULL, NULL);
9166 	if (cmd[0] == delimiter && cmd[1] == '\\' && cmd[2] == '=')
9167 	{
9168 	    garray_T	save_ga = cctx->ctx_instr;
9169 	    char_u	*end;
9170 	    int		expr_res;
9171 	    int		trailing_error;
9172 	    int		instr_count;
9173 	    isn_T	*instr;
9174 	    isn_T	*isn;
9175 
9176 	    cmd += 3;
9177 	    end = skip_substitute(cmd, delimiter);
9178 
9179 	    // Temporarily reset the list of instructions so that the jump
9180 	    // labels are correct.
9181 	    cctx->ctx_instr.ga_len = 0;
9182 	    cctx->ctx_instr.ga_maxlen = 0;
9183 	    cctx->ctx_instr.ga_data = NULL;
9184 	    expr_res = compile_expr0(&cmd, cctx);
9185 	    if (end[-1] == NUL)
9186 		end[-1] = delimiter;
9187 	    cmd = skipwhite(cmd);
9188 	    trailing_error = *cmd != delimiter && *cmd != NUL;
9189 
9190 	    if (expr_res == FAIL || trailing_error
9191 				       || GA_GROW_FAILS(&cctx->ctx_instr, 1))
9192 	    {
9193 		if (trailing_error)
9194 		    semsg(_(e_trailing_arg), cmd);
9195 		clear_instr_ga(&cctx->ctx_instr);
9196 		cctx->ctx_instr = save_ga;
9197 		return NULL;
9198 	    }
9199 
9200 	    // Move the generated instructions into the ISN_SUBSTITUTE
9201 	    // instructions, then restore the list of instructions before
9202 	    // adding the ISN_SUBSTITUTE instruction.
9203 	    instr_count = cctx->ctx_instr.ga_len;
9204 	    instr = cctx->ctx_instr.ga_data;
9205 	    instr[instr_count].isn_type = ISN_FINISH;
9206 
9207 	    cctx->ctx_instr = save_ga;
9208 	    if ((isn = generate_instr(cctx, ISN_SUBSTITUTE)) == NULL)
9209 	    {
9210 		int idx;
9211 
9212 		for (idx = 0; idx < instr_count; ++idx)
9213 		    delete_instr(instr + idx);
9214 		vim_free(instr);
9215 		return NULL;
9216 	    }
9217 	    isn->isn_arg.subs.subs_cmd = vim_strsave(arg);
9218 	    isn->isn_arg.subs.subs_instr = instr;
9219 
9220 	    // skip over flags
9221 	    if (*end == '&')
9222 		++end;
9223 	    while (ASCII_ISALPHA(*end) || *end == '#')
9224 		++end;
9225 	    return end;
9226 	}
9227     }
9228 
9229     return compile_exec(arg, eap, cctx);
9230 }
9231 
9232     static char_u *
9233 compile_redir(char_u *line, exarg_T *eap, cctx_T *cctx)
9234 {
9235     char_u *arg = eap->arg;
9236     lhs_T	*lhs = &cctx->ctx_redir_lhs;
9237 
9238     if (lhs->lhs_name != NULL)
9239     {
9240 	if (STRNCMP(arg, "END", 3) == 0)
9241 	{
9242 	    if (lhs->lhs_append)
9243 	    {
9244 		// First load the current variable value.
9245 		if (compile_load_lhs_with_index(lhs, lhs->lhs_whole,
9246 								 cctx) == FAIL)
9247 		    return NULL;
9248 	    }
9249 
9250 	    // Gets the redirected text and put it on the stack, then store it
9251 	    // in the variable.
9252 	    generate_instr_type(cctx, ISN_REDIREND, &t_string);
9253 
9254 	    if (lhs->lhs_append)
9255 		generate_instr_drop(cctx, ISN_CONCAT, 1);
9256 
9257 	    if (lhs->lhs_has_index)
9258 	    {
9259 		// Use the info in "lhs" to store the value at the index in the
9260 		// list or dict.
9261 		if (compile_assign_unlet(lhs->lhs_whole, lhs, TRUE,
9262 						      &t_string, cctx) == FAIL)
9263 		    return NULL;
9264 	    }
9265 	    else if (generate_store_lhs(cctx, lhs, -1) == FAIL)
9266 		return NULL;
9267 
9268 	    VIM_CLEAR(lhs->lhs_name);
9269 	    VIM_CLEAR(lhs->lhs_whole);
9270 	    return arg + 3;
9271 	}
9272 	emsg(_(e_cannot_nest_redir));
9273 	return NULL;
9274     }
9275 
9276     if (arg[0] == '=' && arg[1] == '>')
9277     {
9278 	int	    append = FALSE;
9279 
9280 	// redirect to a variable is compiled
9281 	arg += 2;
9282 	if (*arg == '>')
9283 	{
9284 	    ++arg;
9285 	    append = TRUE;
9286 	}
9287 	arg = skipwhite(arg);
9288 
9289 	if (compile_assign_lhs(arg, lhs, CMD_redir,
9290 						FALSE, FALSE, 1, cctx) == FAIL)
9291 	    return NULL;
9292 	generate_instr(cctx, ISN_REDIRSTART);
9293 	lhs->lhs_append = append;
9294 	if (lhs->lhs_has_index)
9295 	{
9296 	    lhs->lhs_whole = vim_strnsave(arg, lhs->lhs_varlen_total);
9297 	    if (lhs->lhs_whole == NULL)
9298 		return NULL;
9299 	}
9300 
9301 	return arg + lhs->lhs_varlen_total;
9302     }
9303 
9304     // other redirects are handled like at script level
9305     return compile_exec(line, eap, cctx);
9306 }
9307 
9308 #ifdef FEAT_QUICKFIX
9309     static char_u *
9310 compile_cexpr(char_u *line, exarg_T *eap, cctx_T *cctx)
9311 {
9312     isn_T	*isn;
9313     char_u	*p;
9314 
9315     isn = generate_instr(cctx, ISN_CEXPR_AUCMD);
9316     if (isn == NULL)
9317 	return NULL;
9318     isn->isn_arg.number = eap->cmdidx;
9319 
9320     p = eap->arg;
9321     if (compile_expr0(&p, cctx) == FAIL)
9322 	return NULL;
9323 
9324     isn = generate_instr(cctx, ISN_CEXPR_CORE);
9325     if (isn == NULL)
9326 	return NULL;
9327     isn->isn_arg.cexpr.cexpr_ref = ALLOC_ONE(cexprref_T);
9328     if (isn->isn_arg.cexpr.cexpr_ref == NULL)
9329 	return NULL;
9330     isn->isn_arg.cexpr.cexpr_ref->cer_cmdidx = eap->cmdidx;
9331     isn->isn_arg.cexpr.cexpr_ref->cer_forceit = eap->forceit;
9332     isn->isn_arg.cexpr.cexpr_ref->cer_cmdline = vim_strsave(skipwhite(line));
9333 
9334     return p;
9335 }
9336 #endif
9337 
9338 /*
9339  * Add a function to the list of :def functions.
9340  * This sets "ufunc->uf_dfunc_idx" but the function isn't compiled yet.
9341  */
9342     static int
9343 add_def_function(ufunc_T *ufunc)
9344 {
9345     dfunc_T *dfunc;
9346 
9347     if (def_functions.ga_len == 0)
9348     {
9349 	// The first position is not used, so that a zero uf_dfunc_idx means it
9350 	// wasn't set.
9351 	if (GA_GROW_FAILS(&def_functions, 1))
9352 	    return FAIL;
9353 	++def_functions.ga_len;
9354     }
9355 
9356     // Add the function to "def_functions".
9357     if (GA_GROW_FAILS(&def_functions, 1))
9358 	return FAIL;
9359     dfunc = ((dfunc_T *)def_functions.ga_data) + def_functions.ga_len;
9360     CLEAR_POINTER(dfunc);
9361     dfunc->df_idx = def_functions.ga_len;
9362     ufunc->uf_dfunc_idx = dfunc->df_idx;
9363     dfunc->df_ufunc = ufunc;
9364     dfunc->df_name = vim_strsave(ufunc->uf_name);
9365     ga_init2(&dfunc->df_var_names, sizeof(char_u *), 10);
9366     ++dfunc->df_refcount;
9367     ++def_functions.ga_len;
9368     return OK;
9369 }
9370 
9371 /*
9372  * After ex_function() has collected all the function lines: parse and compile
9373  * the lines into instructions.
9374  * Adds the function to "def_functions".
9375  * When "check_return_type" is set then set ufunc->uf_ret_type to the type of
9376  * the return statement (used for lambda).  When uf_ret_type is already set
9377  * then check that it matches.
9378  * When "profiling" is true add ISN_PROF_START instructions.
9379  * "outer_cctx" is set for a nested function.
9380  * This can be used recursively through compile_lambda(), which may reallocate
9381  * "def_functions".
9382  * Returns OK or FAIL.
9383  */
9384     int
9385 compile_def_function(
9386 	ufunc_T		*ufunc,
9387 	int		check_return_type,
9388 	compiletype_T   compile_type,
9389 	cctx_T		*outer_cctx)
9390 {
9391     char_u	*line = NULL;
9392     char_u	*line_to_free = NULL;
9393     char_u	*p;
9394     char	*errormsg = NULL;	// error message
9395     cctx_T	cctx;
9396     garray_T	*instr;
9397     int		did_emsg_before = did_emsg;
9398     int		did_emsg_silent_before = did_emsg_silent;
9399     int		ret = FAIL;
9400     sctx_T	save_current_sctx = current_sctx;
9401     int		save_estack_compiling = estack_compiling;
9402     int		save_cmod_flags = cmdmod.cmod_flags;
9403     int		do_estack_push;
9404     int		new_def_function = FALSE;
9405 #ifdef FEAT_PROFILE
9406     int		prof_lnum = -1;
9407 #endif
9408     int		debug_lnum = -1;
9409 
9410     // When using a function that was compiled before: Free old instructions.
9411     // The index is reused.  Otherwise add a new entry in "def_functions".
9412     if (ufunc->uf_dfunc_idx > 0)
9413     {
9414 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
9415 							 + ufunc->uf_dfunc_idx;
9416 	isn_T	*instr_dest = NULL;
9417 
9418 	switch (compile_type)
9419 	{
9420 	    case CT_PROFILE:
9421 #ifdef FEAT_PROFILE
9422 			    instr_dest = dfunc->df_instr_prof; break;
9423 #endif
9424 	    case CT_NONE:   instr_dest = dfunc->df_instr; break;
9425 	    case CT_DEBUG:  instr_dest = dfunc->df_instr_debug; break;
9426 	}
9427 	if (instr_dest != NULL)
9428 	    // Was compiled in this mode before: Free old instructions.
9429 	    delete_def_function_contents(dfunc, FALSE);
9430 	ga_clear_strings(&dfunc->df_var_names);
9431     }
9432     else
9433     {
9434 	if (add_def_function(ufunc) == FAIL)
9435 	    return FAIL;
9436 	new_def_function = TRUE;
9437     }
9438 
9439     ufunc->uf_def_status = UF_COMPILING;
9440 
9441     CLEAR_FIELD(cctx);
9442 
9443     cctx.ctx_compile_type = compile_type;
9444     cctx.ctx_ufunc = ufunc;
9445     cctx.ctx_lnum = -1;
9446     cctx.ctx_outer = outer_cctx;
9447     ga_init2(&cctx.ctx_locals, sizeof(lvar_T), 10);
9448     ga_init2(&cctx.ctx_type_stack, sizeof(type_T *), 50);
9449     ga_init2(&cctx.ctx_imports, sizeof(imported_T), 10);
9450     cctx.ctx_type_list = &ufunc->uf_type_list;
9451     ga_init2(&cctx.ctx_instr, sizeof(isn_T), 50);
9452     instr = &cctx.ctx_instr;
9453 
9454     // Set the context to the function, it may be compiled when called from
9455     // another script.  Set the script version to the most modern one.
9456     // The line number will be set in next_line_from_context().
9457     current_sctx = ufunc->uf_script_ctx;
9458     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
9459 
9460     // Don't use the flag from ":legacy" here.
9461     cmdmod.cmod_flags &= ~CMOD_LEGACY;
9462 
9463     // Make sure error messages are OK.
9464     do_estack_push = !estack_top_is_ufunc(ufunc, 1);
9465     if (do_estack_push)
9466 	estack_push_ufunc(ufunc, 1);
9467     estack_compiling = TRUE;
9468 
9469     if (ufunc->uf_def_args.ga_len > 0)
9470     {
9471 	int	count = ufunc->uf_def_args.ga_len;
9472 	int	first_def_arg = ufunc->uf_args.ga_len - count;
9473 	int	i;
9474 	char_u	*arg;
9475 	int	off = STACK_FRAME_SIZE + (ufunc->uf_va_name != NULL ? 1 : 0);
9476 	int	did_set_arg_type = FALSE;
9477 
9478 	// Produce instructions for the default values of optional arguments.
9479 	SOURCING_LNUM = 0;  // line number unknown
9480 	for (i = 0; i < count; ++i)
9481 	{
9482 	    garray_T	*stack = &cctx.ctx_type_stack;
9483 	    type_T	*val_type;
9484 	    int		arg_idx = first_def_arg + i;
9485 	    where_T	where = WHERE_INIT;
9486 	    int		r;
9487 	    int		jump_instr_idx = instr->ga_len;
9488 	    isn_T	*isn;
9489 
9490 	    // Use a JUMP_IF_ARG_SET instruction to skip if the value was given.
9491 	    if (generate_JUMP_IF_ARG_SET(&cctx, i - count - off) == FAIL)
9492 		goto erret;
9493 
9494 	    // Make sure later arguments are not found.
9495 	    ufunc->uf_args_visible = arg_idx;
9496 
9497 	    arg = ((char_u **)(ufunc->uf_def_args.ga_data))[i];
9498 	    r = compile_expr0(&arg, &cctx);
9499 
9500 	    if (r == FAIL)
9501 		goto erret;
9502 
9503 	    // If no type specified use the type of the default value.
9504 	    // Otherwise check that the default value type matches the
9505 	    // specified type.
9506 	    val_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
9507 	    where.wt_index = arg_idx + 1;
9508 	    if (ufunc->uf_arg_types[arg_idx] == &t_unknown)
9509 	    {
9510 		did_set_arg_type = TRUE;
9511 		ufunc->uf_arg_types[arg_idx] = val_type;
9512 	    }
9513 	    else if (check_type(ufunc->uf_arg_types[arg_idx], val_type,
9514 							  TRUE, where) == FAIL)
9515 		goto erret;
9516 
9517 	    if (generate_STORE(&cctx, ISN_STORE, i - count - off, NULL) == FAIL)
9518 		goto erret;
9519 
9520 	    // set instruction index in JUMP_IF_ARG_SET to here
9521 	    isn = ((isn_T *)instr->ga_data) + jump_instr_idx;
9522 	    isn->isn_arg.jumparg.jump_where = instr->ga_len;
9523 	}
9524 
9525 	if (did_set_arg_type)
9526 	    set_function_type(ufunc);
9527     }
9528     ufunc->uf_args_visible = ufunc->uf_args.ga_len;
9529 
9530     /*
9531      * Loop over all the lines of the function and generate instructions.
9532      */
9533     for (;;)
9534     {
9535 	exarg_T	    ea;
9536 	int	    starts_with_colon = FALSE;
9537 	char_u	    *cmd;
9538 	cmdmod_T    local_cmdmod;
9539 
9540 	// Bail out on the first error to avoid a flood of errors and report
9541 	// the right line number when inside try/catch.
9542 	if (did_emsg_before != did_emsg)
9543 	    goto erret;
9544 
9545 	if (line != NULL && *line == '|')
9546 	    // the line continues after a '|'
9547 	    ++line;
9548 	else if (line != NULL && *skipwhite(line) != NUL
9549 		&& !(*line == '#' && (line == cctx.ctx_line_start
9550 						    || VIM_ISWHITE(line[-1]))))
9551 	{
9552 	    semsg(_(e_trailing_arg), line);
9553 	    goto erret;
9554 	}
9555 	else if (line != NULL && vim9_bad_comment(skipwhite(line)))
9556 	    goto erret;
9557 	else
9558 	{
9559 	    line = next_line_from_context(&cctx, FALSE);
9560 	    if (cctx.ctx_lnum >= ufunc->uf_lines.ga_len)
9561 	    {
9562 		// beyond the last line
9563 #ifdef FEAT_PROFILE
9564 		if (cctx.ctx_skip != SKIP_YES)
9565 		    may_generate_prof_end(&cctx, prof_lnum);
9566 #endif
9567 		break;
9568 	    }
9569 	    // Make a copy, splitting off nextcmd and removing trailing spaces
9570 	    // may change it.
9571 	    if (line != NULL)
9572 	    {
9573 		line = vim_strsave(line);
9574 		vim_free(line_to_free);
9575 		line_to_free = line;
9576 	    }
9577 	}
9578 
9579 	CLEAR_FIELD(ea);
9580 	ea.cmdlinep = &line;
9581 	ea.cmd = skipwhite(line);
9582 
9583 	if (*ea.cmd == '#')
9584 	{
9585 	    // "#" starts a comment
9586 	    line = (char_u *)"";
9587 	    continue;
9588 	}
9589 
9590 #ifdef FEAT_PROFILE
9591 	if (cctx.ctx_compile_type == CT_PROFILE && cctx.ctx_lnum != prof_lnum
9592 						  && cctx.ctx_skip != SKIP_YES)
9593 	{
9594 	    may_generate_prof_end(&cctx, prof_lnum);
9595 
9596 	    prof_lnum = cctx.ctx_lnum;
9597 	    generate_instr(&cctx, ISN_PROF_START);
9598 	}
9599 #endif
9600 	if (cctx.ctx_compile_type == CT_DEBUG && cctx.ctx_lnum != debug_lnum
9601 						  && cctx.ctx_skip != SKIP_YES)
9602 	{
9603 	    debug_lnum = cctx.ctx_lnum;
9604 	    generate_instr_debug(&cctx);
9605 	}
9606 	cctx.ctx_prev_lnum = cctx.ctx_lnum + 1;
9607 
9608 	// Some things can be recognized by the first character.
9609 	switch (*ea.cmd)
9610 	{
9611 	    case '}':
9612 		{
9613 		    // "}" ends a block scope
9614 		    scopetype_T stype = cctx.ctx_scope == NULL
9615 					  ? NO_SCOPE : cctx.ctx_scope->se_type;
9616 
9617 		    if (stype == BLOCK_SCOPE)
9618 		    {
9619 			compile_endblock(&cctx);
9620 			line = ea.cmd;
9621 		    }
9622 		    else
9623 		    {
9624 			emsg(_(e_using_rcurly_outside_if_block_scope));
9625 			goto erret;
9626 		    }
9627 		    if (line != NULL)
9628 			line = skipwhite(ea.cmd + 1);
9629 		    continue;
9630 		}
9631 
9632 	    case '{':
9633 		// "{" starts a block scope
9634 		// "{'a': 1}->func() is something else
9635 		if (ends_excmd(*skipwhite(ea.cmd + 1)))
9636 		{
9637 		    line = compile_block(ea.cmd, &cctx);
9638 		    continue;
9639 		}
9640 		break;
9641 	}
9642 
9643 	/*
9644 	 * COMMAND MODIFIERS
9645 	 */
9646 	cctx.ctx_has_cmdmod = FALSE;
9647 	if (parse_command_modifiers(&ea, &errormsg, &local_cmdmod, FALSE)
9648 								       == FAIL)
9649 	{
9650 	    if (errormsg != NULL)
9651 		goto erret;
9652 	    // empty line or comment
9653 	    line = (char_u *)"";
9654 	    continue;
9655 	}
9656 	generate_cmdmods(&cctx, &local_cmdmod);
9657 	undo_cmdmod(&local_cmdmod);
9658 
9659 	// Check if there was a colon after the last command modifier or before
9660 	// the current position.
9661 	for (p = ea.cmd; p >= line; --p)
9662 	{
9663 	    if (*p == ':')
9664 		starts_with_colon = TRUE;
9665 	    if (p < ea.cmd && !VIM_ISWHITE(*p))
9666 		break;
9667 	}
9668 
9669 	// Skip ":call" to get to the function name, unless using :legacy
9670 	p = ea.cmd;
9671 	if (!(local_cmdmod.cmod_flags & CMOD_LEGACY))
9672 	{
9673 	    if (checkforcmd(&ea.cmd, "call", 3))
9674 	    {
9675 		if (*ea.cmd == '(')
9676 		    // not for "call()"
9677 		    ea.cmd = p;
9678 		else
9679 		    ea.cmd = skipwhite(ea.cmd);
9680 	    }
9681 
9682 	    if (!starts_with_colon)
9683 	    {
9684 		int	    assign;
9685 
9686 		// Check for assignment after command modifiers.
9687 		assign = may_compile_assignment(&ea, &line, &cctx);
9688 		if (assign == OK)
9689 		    goto nextline;
9690 		if (assign == FAIL)
9691 		    goto erret;
9692 	    }
9693 	}
9694 
9695 	/*
9696 	 * COMMAND after range
9697 	 * 'text'->func() should not be confused with 'a mark
9698 	 * "++nr" and "--nr" are eval commands
9699 	 */
9700 	cmd = ea.cmd;
9701 	if (!(local_cmdmod.cmod_flags & CMOD_LEGACY)
9702 		&& (starts_with_colon || !(*cmd == '\''
9703 		       || (cmd[0] == cmd[1] && (*cmd == '+' || *cmd == '-')))))
9704 	{
9705 	    ea.cmd = skip_range(ea.cmd, TRUE, NULL);
9706 	    if (ea.cmd > cmd)
9707 	    {
9708 		if (!starts_with_colon)
9709 		{
9710 		    semsg(_(e_colon_required_before_range_str), cmd);
9711 		    goto erret;
9712 		}
9713 		ea.addr_count = 1;
9714 		if (ends_excmd2(line, ea.cmd))
9715 		{
9716 		    // A range without a command: jump to the line.
9717 		    // TODO: compile to a more efficient command, possibly
9718 		    // calling parse_cmd_address().
9719 		    ea.cmdidx = CMD_SIZE;
9720 		    line = compile_exec(line, &ea, &cctx);
9721 		    goto nextline;
9722 		}
9723 	    }
9724 	}
9725 	p = find_ex_command(&ea, NULL,
9726 		starts_with_colon || (local_cmdmod.cmod_flags & CMOD_LEGACY)
9727 						  ? NULL : item_exists, &cctx);
9728 
9729 	if (p == NULL)
9730 	{
9731 	    if (cctx.ctx_skip != SKIP_YES)
9732 		emsg(_(e_ambiguous_use_of_user_defined_command));
9733 	    goto erret;
9734 	}
9735 
9736 	// When using ":legacy cmd" always use compile_exec().
9737 	if (local_cmdmod.cmod_flags & CMOD_LEGACY)
9738 	{
9739 	    char_u *start = ea.cmd;
9740 
9741 	    switch (ea.cmdidx)
9742 	    {
9743 		case CMD_if:
9744 		case CMD_elseif:
9745 		case CMD_else:
9746 		case CMD_endif:
9747 		case CMD_for:
9748 		case CMD_endfor:
9749 		case CMD_continue:
9750 		case CMD_break:
9751 		case CMD_while:
9752 		case CMD_endwhile:
9753 		case CMD_try:
9754 		case CMD_catch:
9755 		case CMD_finally:
9756 		case CMD_endtry:
9757 			semsg(_(e_cannot_use_legacy_with_command_str), ea.cmd);
9758 			goto erret;
9759 		default: break;
9760 	    }
9761 
9762 	    // ":legacy return expr" needs to be handled differently.
9763 	    if (checkforcmd(&start, "return", 4))
9764 		ea.cmdidx = CMD_return;
9765 	    else
9766 		ea.cmdidx = CMD_legacy;
9767 	}
9768 
9769 	if (p == ea.cmd && ea.cmdidx != CMD_SIZE)
9770 	{
9771 	    if (cctx.ctx_skip == SKIP_YES && ea.cmdidx != CMD_eval)
9772 	    {
9773 		line += STRLEN(line);
9774 		goto nextline;
9775 	    }
9776 	    else if (ea.cmdidx != CMD_eval)
9777 	    {
9778 		// CMD_var cannot happen, compile_assignment() above would be
9779 		// used.  Most likely an assignment to a non-existing variable.
9780 		semsg(_(e_command_not_recognized_str), ea.cmd);
9781 		goto erret;
9782 	    }
9783 	}
9784 
9785 	if (cctx.ctx_had_return
9786 		&& ea.cmdidx != CMD_elseif
9787 		&& ea.cmdidx != CMD_else
9788 		&& ea.cmdidx != CMD_endif
9789 		&& ea.cmdidx != CMD_endfor
9790 		&& ea.cmdidx != CMD_endwhile
9791 		&& ea.cmdidx != CMD_catch
9792 		&& ea.cmdidx != CMD_finally
9793 		&& ea.cmdidx != CMD_endtry)
9794 	{
9795 	    emsg(_(e_unreachable_code_after_return));
9796 	    goto erret;
9797 	}
9798 
9799 	p = skipwhite(p);
9800 	if (ea.cmdidx != CMD_SIZE
9801 			    && ea.cmdidx != CMD_write && ea.cmdidx != CMD_read)
9802 	{
9803 	    if (ea.cmdidx >= 0)
9804 		ea.argt = excmd_get_argt(ea.cmdidx);
9805 	    if ((ea.argt & EX_BANG) && *p == '!')
9806 	    {
9807 		ea.forceit = TRUE;
9808 		p = skipwhite(p + 1);
9809 	    }
9810 	}
9811 
9812 	switch (ea.cmdidx)
9813 	{
9814 	    case CMD_def:
9815 		    ea.arg = p;
9816 		    line = compile_nested_function(&ea, &cctx);
9817 		    break;
9818 
9819 	    case CMD_function:
9820 		    // TODO: should we allow this, e.g. to declare a global
9821 		    // function?
9822 		    emsg(_(e_cannot_use_function_inside_def));
9823 		    goto erret;
9824 
9825 	    case CMD_return:
9826 		    line = compile_return(p, check_return_type,
9827 				 local_cmdmod.cmod_flags & CMOD_LEGACY, &cctx);
9828 		    cctx.ctx_had_return = TRUE;
9829 		    break;
9830 
9831 	    case CMD_let:
9832 		    emsg(_(e_cannot_use_let_in_vim9_script));
9833 		    break;
9834 	    case CMD_var:
9835 	    case CMD_final:
9836 	    case CMD_const:
9837 	    case CMD_increment:
9838 	    case CMD_decrement:
9839 		    line = compile_assignment(p, &ea, ea.cmdidx, &cctx);
9840 		    if (line == p)
9841 			line = NULL;
9842 		    break;
9843 
9844 	    case CMD_unlet:
9845 	    case CMD_unlockvar:
9846 	    case CMD_lockvar:
9847 		    line = compile_unletlock(p, &ea, &cctx);
9848 		    break;
9849 
9850 	    case CMD_import:
9851 		    emsg(_(e_import_can_only_be_used_in_script));
9852 		    line = NULL;
9853 		    break;
9854 
9855 	    case CMD_if:
9856 		    line = compile_if(p, &cctx);
9857 		    break;
9858 	    case CMD_elseif:
9859 		    line = compile_elseif(p, &cctx);
9860 		    cctx.ctx_had_return = FALSE;
9861 		    break;
9862 	    case CMD_else:
9863 		    line = compile_else(p, &cctx);
9864 		    cctx.ctx_had_return = FALSE;
9865 		    break;
9866 	    case CMD_endif:
9867 		    line = compile_endif(p, &cctx);
9868 		    break;
9869 
9870 	    case CMD_while:
9871 		    line = compile_while(p, &cctx);
9872 		    break;
9873 	    case CMD_endwhile:
9874 		    line = compile_endwhile(p, &cctx);
9875 		    cctx.ctx_had_return = FALSE;
9876 		    break;
9877 
9878 	    case CMD_for:
9879 		    line = compile_for(p, &cctx);
9880 		    break;
9881 	    case CMD_endfor:
9882 		    line = compile_endfor(p, &cctx);
9883 		    cctx.ctx_had_return = FALSE;
9884 		    break;
9885 	    case CMD_continue:
9886 		    line = compile_continue(p, &cctx);
9887 		    break;
9888 	    case CMD_break:
9889 		    line = compile_break(p, &cctx);
9890 		    break;
9891 
9892 	    case CMD_try:
9893 		    line = compile_try(p, &cctx);
9894 		    break;
9895 	    case CMD_catch:
9896 		    line = compile_catch(p, &cctx);
9897 		    cctx.ctx_had_return = FALSE;
9898 		    break;
9899 	    case CMD_finally:
9900 		    line = compile_finally(p, &cctx);
9901 		    cctx.ctx_had_return = FALSE;
9902 		    break;
9903 	    case CMD_endtry:
9904 		    line = compile_endtry(p, &cctx);
9905 		    cctx.ctx_had_return = FALSE;
9906 		    break;
9907 	    case CMD_throw:
9908 		    line = compile_throw(p, &cctx);
9909 		    break;
9910 
9911 	    case CMD_eval:
9912 		    line = compile_eval(p, &cctx);
9913 		    break;
9914 
9915 	    case CMD_echo:
9916 	    case CMD_echon:
9917 	    case CMD_execute:
9918 	    case CMD_echomsg:
9919 	    case CMD_echoerr:
9920 	    case CMD_echoconsole:
9921 		    line = compile_mult_expr(p, ea.cmdidx, &cctx);
9922 		    break;
9923 
9924 	    case CMD_put:
9925 		    ea.cmd = cmd;
9926 		    line = compile_put(p, &ea, &cctx);
9927 		    break;
9928 
9929 	    case CMD_substitute:
9930 		    if (cctx.ctx_skip == SKIP_YES)
9931 			line = (char_u *)"";
9932 		    else
9933 		    {
9934 			ea.arg = p;
9935 			line = compile_substitute(line, &ea, &cctx);
9936 		    }
9937 		    break;
9938 
9939 	    case CMD_redir:
9940 		    ea.arg = p;
9941 		    line = compile_redir(line, &ea, &cctx);
9942 		    break;
9943 
9944 	    case CMD_cexpr:
9945 	    case CMD_lexpr:
9946 	    case CMD_caddexpr:
9947 	    case CMD_laddexpr:
9948 	    case CMD_cgetexpr:
9949 	    case CMD_lgetexpr:
9950 #ifdef FEAT_QUICKFIX
9951 		    ea.arg = p;
9952 		    line = compile_cexpr(line, &ea, &cctx);
9953 #else
9954 		    ex_ni(&ea);
9955 		    line = NULL;
9956 #endif
9957 		    break;
9958 
9959 	    case CMD_append:
9960 	    case CMD_change:
9961 	    case CMD_insert:
9962 	    case CMD_k:
9963 	    case CMD_t:
9964 	    case CMD_xit:
9965 		    not_in_vim9(&ea);
9966 		    goto erret;
9967 
9968 	    case CMD_SIZE:
9969 		    if (cctx.ctx_skip != SKIP_YES)
9970 		    {
9971 			semsg(_(e_invalid_command_str), ea.cmd);
9972 			goto erret;
9973 		    }
9974 		    // We don't check for a next command here.
9975 		    line = (char_u *)"";
9976 		    break;
9977 
9978 	    case CMD_lua:
9979 	    case CMD_mzscheme:
9980 	    case CMD_perl:
9981 	    case CMD_py3:
9982 	    case CMD_python3:
9983 	    case CMD_python:
9984 	    case CMD_pythonx:
9985 	    case CMD_ruby:
9986 	    case CMD_tcl:
9987 		    ea.arg = p;
9988 		    if (vim_strchr(line, '\n') == NULL)
9989 			line = compile_exec(line, &ea, &cctx);
9990 		    else
9991 			// heredoc lines have been concatenated with NL
9992 			// characters in get_function_body()
9993 			line = compile_script(line, &cctx);
9994 		    break;
9995 
9996 	    default:
9997 		    // Not recognized, execute with do_cmdline_cmd().
9998 		    ea.arg = p;
9999 		    line = compile_exec(line, &ea, &cctx);
10000 		    break;
10001 	}
10002 nextline:
10003 	if (line == NULL)
10004 	    goto erret;
10005 	line = skipwhite(line);
10006 
10007 	// Undo any command modifiers.
10008 	generate_undo_cmdmods(&cctx);
10009 
10010 	if (cctx.ctx_type_stack.ga_len < 0)
10011 	{
10012 	    iemsg("Type stack underflow");
10013 	    goto erret;
10014 	}
10015     }
10016 
10017     if (cctx.ctx_scope != NULL)
10018     {
10019 	if (cctx.ctx_scope->se_type == IF_SCOPE)
10020 	    emsg(_(e_endif));
10021 	else if (cctx.ctx_scope->se_type == WHILE_SCOPE)
10022 	    emsg(_(e_endwhile));
10023 	else if (cctx.ctx_scope->se_type == FOR_SCOPE)
10024 	    emsg(_(e_endfor));
10025 	else
10026 	    emsg(_(e_missing_rcurly));
10027 	goto erret;
10028     }
10029 
10030     if (!cctx.ctx_had_return)
10031     {
10032 	if (ufunc->uf_ret_type->tt_type == VAR_UNKNOWN)
10033 	    ufunc->uf_ret_type = &t_void;
10034 	else if (ufunc->uf_ret_type->tt_type != VAR_VOID)
10035 	{
10036 	    emsg(_(e_missing_return_statement));
10037 	    goto erret;
10038 	}
10039 
10040 	// Return void if there is no return at the end.
10041 	generate_instr(&cctx, ISN_RETURN_VOID);
10042     }
10043 
10044     // When compiled with ":silent!" and there was an error don't consider the
10045     // function compiled.
10046     if (emsg_silent == 0 || did_emsg_silent == did_emsg_silent_before)
10047     {
10048 	dfunc_T	*dfunc = ((dfunc_T *)def_functions.ga_data)
10049 							 + ufunc->uf_dfunc_idx;
10050 	dfunc->df_deleted = FALSE;
10051 	dfunc->df_script_seq = current_sctx.sc_seq;
10052 #ifdef FEAT_PROFILE
10053 	if (cctx.ctx_compile_type == CT_PROFILE)
10054 	{
10055 	    dfunc->df_instr_prof = instr->ga_data;
10056 	    dfunc->df_instr_prof_count = instr->ga_len;
10057 	}
10058 	else
10059 #endif
10060 	if (cctx.ctx_compile_type == CT_DEBUG)
10061 	{
10062 	    dfunc->df_instr_debug = instr->ga_data;
10063 	    dfunc->df_instr_debug_count = instr->ga_len;
10064 	}
10065 	else
10066 	{
10067 	    dfunc->df_instr = instr->ga_data;
10068 	    dfunc->df_instr_count = instr->ga_len;
10069 	}
10070 	dfunc->df_varcount = dfunc->df_var_names.ga_len;
10071 	dfunc->df_has_closure = cctx.ctx_has_closure;
10072 	if (cctx.ctx_outer_used)
10073 	    ufunc->uf_flags |= FC_CLOSURE;
10074 	ufunc->uf_def_status = UF_COMPILED;
10075     }
10076 
10077     ret = OK;
10078 
10079 erret:
10080     if (ufunc->uf_def_status == UF_COMPILING)
10081     {
10082 	dfunc_T	*dfunc = ((dfunc_T *)def_functions.ga_data)
10083 							 + ufunc->uf_dfunc_idx;
10084 
10085 	// Compiling aborted, free the generated instructions.
10086 	clear_instr_ga(instr);
10087 	VIM_CLEAR(dfunc->df_name);
10088 	ga_clear_strings(&dfunc->df_var_names);
10089 
10090 	// If using the last entry in the table and it was added above, we
10091 	// might as well remove it.
10092 	if (!dfunc->df_deleted && new_def_function
10093 			    && ufunc->uf_dfunc_idx == def_functions.ga_len - 1)
10094 	{
10095 	    --def_functions.ga_len;
10096 	    ufunc->uf_dfunc_idx = 0;
10097 	}
10098 	ufunc->uf_def_status = UF_COMPILE_ERROR;
10099 
10100 	while (cctx.ctx_scope != NULL)
10101 	    drop_scope(&cctx);
10102 
10103 	if (errormsg != NULL)
10104 	    emsg(errormsg);
10105 	else if (did_emsg == did_emsg_before)
10106 	    emsg(_(e_compiling_def_function_failed));
10107     }
10108 
10109     if (cctx.ctx_redir_lhs.lhs_name != NULL)
10110     {
10111 	if (ret == OK)
10112 	{
10113 	    emsg(_(e_missing_redir_end));
10114 	    ret = FAIL;
10115 	}
10116 	vim_free(cctx.ctx_redir_lhs.lhs_name);
10117 	vim_free(cctx.ctx_redir_lhs.lhs_whole);
10118     }
10119 
10120     current_sctx = save_current_sctx;
10121     estack_compiling = save_estack_compiling;
10122     cmdmod.cmod_flags =	save_cmod_flags;
10123     if (do_estack_push)
10124 	estack_pop();
10125 
10126     vim_free(line_to_free);
10127     free_imported(&cctx);
10128     free_locals(&cctx);
10129     ga_clear(&cctx.ctx_type_stack);
10130     return ret;
10131 }
10132 
10133     void
10134 set_function_type(ufunc_T *ufunc)
10135 {
10136     int varargs = ufunc->uf_va_name != NULL;
10137     int argcount = ufunc->uf_args.ga_len;
10138 
10139     // Create a type for the function, with the return type and any
10140     // argument types.
10141     // A vararg is included in uf_args.ga_len but not in uf_arg_types.
10142     // The type is included in "tt_args".
10143     if (argcount > 0 || varargs)
10144     {
10145 	if (ufunc->uf_type_list.ga_itemsize == 0)
10146 	    ga_init2(&ufunc->uf_type_list, sizeof(type_T *), 10);
10147 	ufunc->uf_func_type = alloc_func_type(ufunc->uf_ret_type,
10148 					   argcount, &ufunc->uf_type_list);
10149 	// Add argument types to the function type.
10150 	if (func_type_add_arg_types(ufunc->uf_func_type,
10151 				    argcount + varargs,
10152 				    &ufunc->uf_type_list) == FAIL)
10153 	    return;
10154 	ufunc->uf_func_type->tt_argcount = argcount + varargs;
10155 	ufunc->uf_func_type->tt_min_argcount =
10156 				      argcount - ufunc->uf_def_args.ga_len;
10157 	if (ufunc->uf_arg_types == NULL)
10158 	{
10159 	    int i;
10160 
10161 	    // lambda does not have argument types.
10162 	    for (i = 0; i < argcount; ++i)
10163 		ufunc->uf_func_type->tt_args[i] = &t_any;
10164 	}
10165 	else
10166 	    mch_memmove(ufunc->uf_func_type->tt_args,
10167 			 ufunc->uf_arg_types, sizeof(type_T *) * argcount);
10168 	if (varargs)
10169 	{
10170 	    ufunc->uf_func_type->tt_args[argcount] =
10171 		   ufunc->uf_va_type == NULL ? &t_list_any : ufunc->uf_va_type;
10172 	    ufunc->uf_func_type->tt_flags = TTFLAG_VARARGS;
10173 	}
10174     }
10175     else
10176 	// No arguments, can use a predefined type.
10177 	ufunc->uf_func_type = get_func_type(ufunc->uf_ret_type,
10178 					   argcount, &ufunc->uf_type_list);
10179 }
10180 
10181 
10182 /*
10183  * Delete an instruction, free what it contains.
10184  */
10185     void
10186 delete_instr(isn_T *isn)
10187 {
10188     switch (isn->isn_type)
10189     {
10190 	case ISN_DEF:
10191 	case ISN_EXEC:
10192 	case ISN_EXEC_SPLIT:
10193 	case ISN_LEGACY_EVAL:
10194 	case ISN_LOADAUTO:
10195 	case ISN_LOADB:
10196 	case ISN_LOADENV:
10197 	case ISN_LOADG:
10198 	case ISN_LOADOPT:
10199 	case ISN_LOADT:
10200 	case ISN_LOADW:
10201 	case ISN_PUSHEXC:
10202 	case ISN_PUSHFUNC:
10203 	case ISN_PUSHS:
10204 	case ISN_RANGE:
10205 	case ISN_STOREAUTO:
10206 	case ISN_STOREB:
10207 	case ISN_STOREENV:
10208 	case ISN_STOREG:
10209 	case ISN_STORET:
10210 	case ISN_STOREW:
10211 	case ISN_STRINGMEMBER:
10212 	    vim_free(isn->isn_arg.string);
10213 	    break;
10214 
10215 	case ISN_SUBSTITUTE:
10216 	    {
10217 		int	idx;
10218 		isn_T	*list = isn->isn_arg.subs.subs_instr;
10219 
10220 		vim_free(isn->isn_arg.subs.subs_cmd);
10221 		for (idx = 0; list[idx].isn_type != ISN_FINISH; ++idx)
10222 		    delete_instr(list + idx);
10223 		vim_free(list);
10224 	    }
10225 	    break;
10226 
10227 	case ISN_INSTR:
10228 	    {
10229 		int	idx;
10230 		isn_T	*list = isn->isn_arg.instr;
10231 
10232 		for (idx = 0; list[idx].isn_type != ISN_FINISH; ++idx)
10233 		    delete_instr(list + idx);
10234 		vim_free(list);
10235 	    }
10236 	    break;
10237 
10238 	case ISN_LOADS:
10239 	case ISN_STORES:
10240 	    vim_free(isn->isn_arg.loadstore.ls_name);
10241 	    break;
10242 
10243 	case ISN_UNLET:
10244 	case ISN_UNLETENV:
10245 	    vim_free(isn->isn_arg.unlet.ul_name);
10246 	    break;
10247 
10248 	case ISN_STOREOPT:
10249 	    vim_free(isn->isn_arg.storeopt.so_name);
10250 	    break;
10251 
10252 	case ISN_PUSHBLOB:   // push blob isn_arg.blob
10253 	    blob_unref(isn->isn_arg.blob);
10254 	    break;
10255 
10256 	case ISN_PUSHJOB:
10257 #ifdef FEAT_JOB_CHANNEL
10258 	    job_unref(isn->isn_arg.job);
10259 #endif
10260 	    break;
10261 
10262 	case ISN_PUSHCHANNEL:
10263 #ifdef FEAT_JOB_CHANNEL
10264 	    channel_unref(isn->isn_arg.channel);
10265 #endif
10266 	    break;
10267 
10268 	case ISN_UCALL:
10269 	    vim_free(isn->isn_arg.ufunc.cuf_name);
10270 	    break;
10271 
10272 	case ISN_FUNCREF:
10273 	    {
10274 		dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
10275 					       + isn->isn_arg.funcref.fr_func;
10276 		ufunc_T *ufunc = dfunc->df_ufunc;
10277 
10278 		if (ufunc != NULL && func_name_refcount(ufunc->uf_name))
10279 		    func_ptr_unref(ufunc);
10280 	    }
10281 	    break;
10282 
10283 	case ISN_DCALL:
10284 	    {
10285 		dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
10286 					       + isn->isn_arg.dfunc.cdf_idx;
10287 
10288 		if (dfunc->df_ufunc != NULL
10289 			       && func_name_refcount(dfunc->df_ufunc->uf_name))
10290 		    func_ptr_unref(dfunc->df_ufunc);
10291 	    }
10292 	    break;
10293 
10294 	case ISN_NEWFUNC:
10295 	    {
10296 		char_u  *lambda = isn->isn_arg.newfunc.nf_lambda;
10297 		ufunc_T *ufunc = find_func_even_dead(lambda, TRUE, NULL);
10298 
10299 		if (ufunc != NULL)
10300 		{
10301 		    unlink_def_function(ufunc);
10302 		    func_ptr_unref(ufunc);
10303 		}
10304 
10305 		vim_free(lambda);
10306 		vim_free(isn->isn_arg.newfunc.nf_global);
10307 	    }
10308 	    break;
10309 
10310 	case ISN_CHECKTYPE:
10311 	case ISN_SETTYPE:
10312 	    free_type(isn->isn_arg.type.ct_type);
10313 	    break;
10314 
10315 	case ISN_CMDMOD:
10316 	    vim_regfree(isn->isn_arg.cmdmod.cf_cmdmod
10317 					       ->cmod_filter_regmatch.regprog);
10318 	    vim_free(isn->isn_arg.cmdmod.cf_cmdmod);
10319 	    break;
10320 
10321 	case ISN_LOADSCRIPT:
10322 	case ISN_STORESCRIPT:
10323 	    vim_free(isn->isn_arg.script.scriptref);
10324 	    break;
10325 
10326 	case ISN_TRY:
10327 	    vim_free(isn->isn_arg.try.try_ref);
10328 	    break;
10329 
10330 	case ISN_CEXPR_CORE:
10331 	    vim_free(isn->isn_arg.cexpr.cexpr_ref->cer_cmdline);
10332 	    vim_free(isn->isn_arg.cexpr.cexpr_ref);
10333 	    break;
10334 
10335 	case ISN_2BOOL:
10336 	case ISN_2STRING:
10337 	case ISN_2STRING_ANY:
10338 	case ISN_ADDBLOB:
10339 	case ISN_ADDLIST:
10340 	case ISN_ANYINDEX:
10341 	case ISN_ANYSLICE:
10342 	case ISN_BCALL:
10343 	case ISN_BLOBAPPEND:
10344 	case ISN_BLOBINDEX:
10345 	case ISN_BLOBSLICE:
10346 	case ISN_CATCH:
10347 	case ISN_CEXPR_AUCMD:
10348 	case ISN_CHECKLEN:
10349 	case ISN_CHECKNR:
10350 	case ISN_CMDMOD_REV:
10351 	case ISN_COMPAREANY:
10352 	case ISN_COMPAREBLOB:
10353 	case ISN_COMPAREBOOL:
10354 	case ISN_COMPAREDICT:
10355 	case ISN_COMPAREFLOAT:
10356 	case ISN_COMPAREFUNC:
10357 	case ISN_COMPARELIST:
10358 	case ISN_COMPARENR:
10359 	case ISN_COMPARESPECIAL:
10360 	case ISN_COMPARESTRING:
10361 	case ISN_CONCAT:
10362 	case ISN_COND2BOOL:
10363 	case ISN_DEBUG:
10364 	case ISN_DROP:
10365 	case ISN_ECHO:
10366 	case ISN_ECHOCONSOLE:
10367 	case ISN_ECHOERR:
10368 	case ISN_ECHOMSG:
10369 	case ISN_ENDTRY:
10370 	case ISN_EXECCONCAT:
10371 	case ISN_EXECUTE:
10372 	case ISN_FINALLY:
10373 	case ISN_FINISH:
10374 	case ISN_FOR:
10375 	case ISN_GETITEM:
10376 	case ISN_JUMP:
10377 	case ISN_JUMP_IF_ARG_SET:
10378 	case ISN_LISTAPPEND:
10379 	case ISN_LISTINDEX:
10380 	case ISN_LISTSLICE:
10381 	case ISN_LOAD:
10382 	case ISN_LOADBDICT:
10383 	case ISN_LOADGDICT:
10384 	case ISN_LOADOUTER:
10385 	case ISN_LOADREG:
10386 	case ISN_LOADTDICT:
10387 	case ISN_LOADV:
10388 	case ISN_LOADWDICT:
10389 	case ISN_LOCKCONST:
10390 	case ISN_MEMBER:
10391 	case ISN_NEGATENR:
10392 	case ISN_NEWDICT:
10393 	case ISN_NEWLIST:
10394 	case ISN_OPANY:
10395 	case ISN_OPFLOAT:
10396 	case ISN_OPNR:
10397 	case ISN_PCALL:
10398 	case ISN_PCALL_END:
10399 	case ISN_PROF_END:
10400 	case ISN_PROF_START:
10401 	case ISN_PUSHBOOL:
10402 	case ISN_PUSHF:
10403 	case ISN_PUSHNR:
10404 	case ISN_PUSHSPEC:
10405 	case ISN_PUT:
10406 	case ISN_REDIREND:
10407 	case ISN_REDIRSTART:
10408 	case ISN_RETURN:
10409 	case ISN_RETURN_VOID:
10410 	case ISN_SHUFFLE:
10411 	case ISN_SLICE:
10412 	case ISN_STORE:
10413 	case ISN_STOREINDEX:
10414 	case ISN_STORENR:
10415 	case ISN_STOREOUTER:
10416 	case ISN_STORERANGE:
10417 	case ISN_STOREREG:
10418 	case ISN_STOREV:
10419 	case ISN_STRINDEX:
10420 	case ISN_STRSLICE:
10421 	case ISN_THROW:
10422 	case ISN_TRYCONT:
10423 	case ISN_UNLETINDEX:
10424 	case ISN_UNLETRANGE:
10425 	case ISN_UNPACK:
10426 	    // nothing allocated
10427 	    break;
10428     }
10429 }
10430 
10431 /*
10432  * Free all instructions for "dfunc" except df_name.
10433  */
10434     static void
10435 delete_def_function_contents(dfunc_T *dfunc, int mark_deleted)
10436 {
10437     int idx;
10438 
10439     ga_clear(&dfunc->df_def_args_isn);
10440     ga_clear_strings(&dfunc->df_var_names);
10441 
10442     if (dfunc->df_instr != NULL)
10443     {
10444 	for (idx = 0; idx < dfunc->df_instr_count; ++idx)
10445 	    delete_instr(dfunc->df_instr + idx);
10446 	VIM_CLEAR(dfunc->df_instr);
10447 	dfunc->df_instr = NULL;
10448     }
10449     if (dfunc->df_instr_debug != NULL)
10450     {
10451 	for (idx = 0; idx < dfunc->df_instr_debug_count; ++idx)
10452 	    delete_instr(dfunc->df_instr_debug + idx);
10453 	VIM_CLEAR(dfunc->df_instr_debug);
10454 	dfunc->df_instr_debug = NULL;
10455     }
10456 #ifdef FEAT_PROFILE
10457     if (dfunc->df_instr_prof != NULL)
10458     {
10459 	for (idx = 0; idx < dfunc->df_instr_prof_count; ++idx)
10460 	    delete_instr(dfunc->df_instr_prof + idx);
10461 	VIM_CLEAR(dfunc->df_instr_prof);
10462 	dfunc->df_instr_prof = NULL;
10463     }
10464 #endif
10465 
10466     if (mark_deleted)
10467 	dfunc->df_deleted = TRUE;
10468     if (dfunc->df_ufunc != NULL)
10469 	dfunc->df_ufunc->uf_def_status = UF_NOT_COMPILED;
10470 }
10471 
10472 /*
10473  * When a user function is deleted, clear the contents of any associated def
10474  * function, unless another user function still uses it.
10475  * The position in def_functions can be re-used.
10476  */
10477     void
10478 unlink_def_function(ufunc_T *ufunc)
10479 {
10480     if (ufunc->uf_dfunc_idx > 0)
10481     {
10482 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
10483 							 + ufunc->uf_dfunc_idx;
10484 
10485 	if (--dfunc->df_refcount <= 0)
10486 	    delete_def_function_contents(dfunc, TRUE);
10487 	ufunc->uf_def_status = UF_NOT_COMPILED;
10488 	ufunc->uf_dfunc_idx = 0;
10489 	if (dfunc->df_ufunc == ufunc)
10490 	    dfunc->df_ufunc = NULL;
10491     }
10492 }
10493 
10494 /*
10495  * Used when a user function refers to an existing dfunc.
10496  */
10497     void
10498 link_def_function(ufunc_T *ufunc)
10499 {
10500     if (ufunc->uf_dfunc_idx > 0)
10501     {
10502 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
10503 							 + ufunc->uf_dfunc_idx;
10504 
10505 	++dfunc->df_refcount;
10506     }
10507 }
10508 
10509 #if defined(EXITFREE) || defined(PROTO)
10510 /*
10511  * Free all functions defined with ":def".
10512  */
10513     void
10514 free_def_functions(void)
10515 {
10516     int idx;
10517 
10518     for (idx = 0; idx < def_functions.ga_len; ++idx)
10519     {
10520 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data) + idx;
10521 
10522 	delete_def_function_contents(dfunc, TRUE);
10523 	vim_free(dfunc->df_name);
10524     }
10525 
10526     ga_clear(&def_functions);
10527 }
10528 #endif
10529 
10530 
10531 #endif // FEAT_EVAL
10532