xref: /vim-8.2.3635/src/vim9compile.c (revision ae0f151d)
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 /*
118  * Context for compiling lines of Vim script.
119  * Stores info about the local variables and condition stack.
120  */
121 struct cctx_S {
122     ufunc_T	*ctx_ufunc;	    // current function
123     int		ctx_lnum;	    // line number in current function
124     char_u	*ctx_line_start;    // start of current line or NULL
125     garray_T	ctx_instr;	    // generated instructions
126 
127     int		ctx_profiling;	    // when TRUE generate ISN_PROF_START
128 
129     garray_T	ctx_locals;	    // currently visible local variables
130     int		ctx_locals_count;   // total number of local variables
131 
132     int		ctx_has_closure;    // set to one if a closures was created in
133 				    // the function
134 
135     garray_T	ctx_imports;	    // imported items
136 
137     skip_T	ctx_skip;
138     scope_T	*ctx_scope;	    // current scope, NULL at toplevel
139     int		ctx_had_return;	    // last seen statement was "return"
140 
141     cctx_T	*ctx_outer;	    // outer scope for lambda or nested
142 				    // function
143     int		ctx_outer_used;	    // var in ctx_outer was used
144 
145     garray_T	ctx_type_stack;	    // type of each item on the stack
146     garray_T	*ctx_type_list;	    // list of pointers to allocated types
147 
148     int		ctx_has_cmdmod;	    // ISN_CMDMOD was generated
149 };
150 
151 static void delete_def_function_contents(dfunc_T *dfunc, int mark_deleted);
152 
153 /*
154  * Lookup variable "name" in the local scope and return it in "lvar".
155  * "lvar->lv_from_outer" is incremented accordingly.
156  * If "lvar" is NULL only check if the variable can be found.
157  * Return FAIL if not found.
158  */
159     static int
160 lookup_local(char_u *name, size_t len, lvar_T *lvar, cctx_T *cctx)
161 {
162     int	    idx;
163     lvar_T  *lvp;
164 
165     if (len == 0)
166 	return FAIL;
167 
168     // Find local in current function scope.
169     for (idx = 0; idx < cctx->ctx_locals.ga_len; ++idx)
170     {
171 	lvp = ((lvar_T *)cctx->ctx_locals.ga_data) + idx;
172 	if (STRNCMP(name, lvp->lv_name, len) == 0
173 					       && STRLEN(lvp->lv_name) == len)
174 	{
175 	    if (lvar != NULL)
176 	    {
177 		*lvar = *lvp;
178 		lvar->lv_from_outer = 0;
179 	    }
180 	    return OK;
181 	}
182     }
183 
184     // Find local in outer function scope.
185     if (cctx->ctx_outer != NULL)
186     {
187 	if (lookup_local(name, len, lvar, cctx->ctx_outer) == OK)
188 	{
189 	    if (lvar != NULL)
190 	    {
191 		cctx->ctx_outer_used = TRUE;
192 		++lvar->lv_from_outer;
193 	    }
194 	    return OK;
195 	}
196     }
197 
198     return FAIL;
199 }
200 
201 /*
202  * Lookup an argument in the current function and an enclosing function.
203  * Returns the argument index in "idxp"
204  * Returns the argument type in "type"
205  * Sets "gen_load_outer" to TRUE if found in outer scope.
206  * Returns OK when found, FAIL otherwise.
207  */
208     static int
209 arg_exists(
210 	char_u	*name,
211 	size_t	len,
212 	int	*idxp,
213 	type_T	**type,
214 	int	*gen_load_outer,
215 	cctx_T	*cctx)
216 {
217     int	    idx;
218     char_u  *va_name;
219 
220     if (len == 0)
221 	return FAIL;
222     for (idx = 0; idx < cctx->ctx_ufunc->uf_args.ga_len; ++idx)
223     {
224 	char_u *arg = FUNCARG(cctx->ctx_ufunc, idx);
225 
226 	if (STRNCMP(name, arg, len) == 0 && arg[len] == NUL)
227 	{
228 	    if (idxp != NULL)
229 	    {
230 		// Arguments are located above the frame pointer.  One further
231 		// if there is a vararg argument
232 		*idxp = idx - (cctx->ctx_ufunc->uf_args.ga_len
233 							    + STACK_FRAME_SIZE)
234 			      + (cctx->ctx_ufunc->uf_va_name != NULL ? -1 : 0);
235 
236 		if (cctx->ctx_ufunc->uf_arg_types != NULL)
237 		    *type = cctx->ctx_ufunc->uf_arg_types[idx];
238 		else
239 		    *type = &t_any;
240 	    }
241 	    return OK;
242 	}
243     }
244 
245     va_name = cctx->ctx_ufunc->uf_va_name;
246     if (va_name != NULL
247 		    && STRNCMP(name, va_name, len) == 0 && va_name[len] == NUL)
248     {
249 	if (idxp != NULL)
250 	{
251 	    // varargs is always the last argument
252 	    *idxp = -STACK_FRAME_SIZE - 1;
253 	    *type = cctx->ctx_ufunc->uf_va_type;
254 	}
255 	return OK;
256     }
257 
258     if (cctx->ctx_outer != NULL)
259     {
260 	// Lookup the name for an argument of the outer function.
261 	if (arg_exists(name, len, idxp, type, gen_load_outer, cctx->ctx_outer)
262 									 == OK)
263 	{
264 	    if (gen_load_outer != NULL)
265 		++*gen_load_outer;
266 	    return OK;
267 	}
268     }
269 
270     return FAIL;
271 }
272 
273 /*
274  * Lookup a script-local variable in the current script, possibly defined in a
275  * block that contains the function "cctx->ctx_ufunc".
276  * "cctx" is NULL at the script level.
277  * If "len" is <= 0 "name" must be NUL terminated.
278  * Return NULL when not found.
279  */
280     static sallvar_T *
281 find_script_var(char_u *name, size_t len, cctx_T *cctx)
282 {
283     scriptitem_T    *si = SCRIPT_ITEM(current_sctx.sc_sid);
284     hashitem_T	    *hi;
285     int		    cc;
286     sallvar_T	    *sav;
287     ufunc_T	    *ufunc;
288 
289     // Find the list of all script variables with the right name.
290     if (len > 0)
291     {
292 	cc = name[len];
293 	name[len] = NUL;
294     }
295     hi = hash_find(&si->sn_all_vars.dv_hashtab, name);
296     if (len > 0)
297 	name[len] = cc;
298     if (HASHITEM_EMPTY(hi))
299 	return NULL;
300 
301     sav = HI2SAV(hi);
302     if (sav->sav_block_id == 0 || cctx == NULL)
303 	// variable defined in the script scope or not in a function.
304 	return sav;
305 
306     // Go over the variables with this name and find one that was visible
307     // from the function.
308     ufunc = cctx->ctx_ufunc;
309     while (sav != NULL)
310     {
311 	int idx;
312 
313 	// Go over the blocks that this function was defined in.  If the
314 	// variable block ID matches it was visible to the function.
315 	for (idx = 0; idx < ufunc->uf_block_depth; ++idx)
316 	    if (ufunc->uf_block_ids[idx] == sav->sav_block_id)
317 		return sav;
318 	sav = sav->sav_next;
319     }
320 
321     return NULL;
322 }
323 
324 /*
325  * Return TRUE if the script context is Vim9 script.
326  */
327     static int
328 script_is_vim9()
329 {
330     return SCRIPT_ITEM(current_sctx.sc_sid)->sn_version == SCRIPT_VERSION_VIM9;
331 }
332 
333 /*
334  * Lookup a variable (without s: prefix) in the current script.
335  * If "vim9script" is TRUE the script must be Vim9 script.  Used for "var"
336  * without "s:".
337  * "cctx" is NULL at the script level.
338  * Returns OK or FAIL.
339  */
340     int
341 script_var_exists(char_u *name, size_t len, int vim9script, cctx_T *cctx)
342 {
343     int		    is_vim9_script;
344 
345     if (current_sctx.sc_sid <= 0)
346 	return FAIL;
347     is_vim9_script = script_is_vim9();
348     if (vim9script && !is_vim9_script)
349 	return FAIL;
350     if (is_vim9_script)
351     {
352 	// Check script variables that were visible where the function was
353 	// defined.
354 	if (find_script_var(name, len, cctx) != NULL)
355 	    return OK;
356     }
357     else
358     {
359 	hashtab_T	*ht = &SCRIPT_VARS(current_sctx.sc_sid);
360 	dictitem_T	*di;
361 	int		cc;
362 
363 	// Check script variables that are currently visible
364 	cc = name[len];
365 	name[len] = NUL;
366 	di = find_var_in_ht(ht, 0, name, TRUE);
367 	name[len] = cc;
368 	if (di != NULL)
369 	    return OK;
370     }
371 
372     return FAIL;
373 }
374 
375 /*
376  * Return TRUE if "name" is a local variable, argument, script variable or
377  * imported.
378  */
379     static int
380 variable_exists(char_u *name, size_t len, cctx_T *cctx)
381 {
382     return (cctx != NULL
383 		&& (lookup_local(name, len, NULL, cctx) == OK
384 		    || arg_exists(name, len, NULL, NULL, NULL, cctx) == OK))
385 	    || script_var_exists(name, len, FALSE, cctx) == OK
386 	    || find_imported(name, len, cctx) != NULL;
387 }
388 
389 /*
390  * Return TRUE if "name" is a local variable, argument, script variable,
391  * imported or function.
392  */
393     static int
394 item_exists(char_u *name, size_t len, int cmd UNUSED, cctx_T *cctx)
395 {
396     int	    is_global;
397     char_u  *p;
398 
399     if (variable_exists(name, len, cctx))
400 	return TRUE;
401 
402     // This is similar to what is in lookup_scriptitem():
403     // Find a function, so that a following "->" works.
404     // Require "(" or "->" to follow, "Cmd" is a user command while "Cmd()" is
405     // a function call.
406     p = skipwhite(name + len);
407 
408     if (name[len] == '(' || (p[0] == '-' && p[1] == '>'))
409     {
410 	// Do not check for an internal function, since it might also be a
411 	// valid command, such as ":split" versuse "split()".
412 	// Skip "g:" before a function name.
413 	is_global = (name[0] == 'g' && name[1] == ':');
414 	return find_func(is_global ? name + 2 : name, is_global, cctx) != NULL;
415     }
416     return FALSE;
417 }
418 
419 /*
420  * Check if "p[len]" is already defined, either in script "import_sid" or in
421  * compilation context "cctx".  "cctx" is NULL at the script level.
422  * Does not check the global namespace.
423  * If "is_arg" is TRUE the error message is for an argument name.
424  * Return FAIL and give an error if it defined.
425  */
426     int
427 check_defined(char_u *p, size_t len, cctx_T *cctx, int is_arg)
428 {
429     int		c = p[len];
430     ufunc_T	*ufunc = NULL;
431 
432     if (script_var_exists(p, len, FALSE, cctx) == OK)
433     {
434 	if (is_arg)
435 	    semsg(_(e_argument_already_declared_in_script_str), p);
436 	else
437 	    semsg(_(e_variable_already_declared_in_script_str), p);
438 	return FAIL;
439     }
440 
441     p[len] = NUL;
442     if ((cctx != NULL
443 		&& (lookup_local(p, len, NULL, cctx) == OK
444 		    || arg_exists(p, len, NULL, NULL, NULL, cctx) == OK))
445 	    || find_imported(p, len, cctx) != NULL
446 	    || (ufunc = find_func_even_dead(p, FALSE, cctx)) != NULL)
447     {
448 	// A local or script-local function can shadow a global function.
449 	if (ufunc == NULL || !func_is_global(ufunc)
450 		|| (p[0] == 'g' && p[1] == ':'))
451 	{
452 	    if (is_arg)
453 		semsg(_(e_argument_name_shadows_existing_variable_str), p);
454 	    else
455 		semsg(_(e_name_already_defined_str), p);
456 	    p[len] = c;
457 	    return FAIL;
458 	}
459     }
460     p[len] = c;
461     return OK;
462 }
463 
464 
465 /////////////////////////////////////////////////////////////////////
466 // Following generate_ functions expect the caller to call ga_grow().
467 
468 #define RETURN_NULL_IF_SKIP(cctx) if (cctx->ctx_skip == SKIP_YES) return NULL
469 #define RETURN_OK_IF_SKIP(cctx) if (cctx->ctx_skip == SKIP_YES) return OK
470 
471 /*
472  * Generate an instruction without arguments.
473  * Returns a pointer to the new instruction, NULL if failed.
474  */
475     static isn_T *
476 generate_instr(cctx_T *cctx, isntype_T isn_type)
477 {
478     garray_T	*instr = &cctx->ctx_instr;
479     isn_T	*isn;
480 
481     RETURN_NULL_IF_SKIP(cctx);
482     if (ga_grow(instr, 1) == FAIL)
483 	return NULL;
484     isn = ((isn_T *)instr->ga_data) + instr->ga_len;
485     isn->isn_type = isn_type;
486     isn->isn_lnum = cctx->ctx_lnum + 1;
487     ++instr->ga_len;
488 
489     return isn;
490 }
491 
492 /*
493  * Generate an instruction without arguments.
494  * "drop" will be removed from the stack.
495  * Returns a pointer to the new instruction, NULL if failed.
496  */
497     static isn_T *
498 generate_instr_drop(cctx_T *cctx, isntype_T isn_type, int drop)
499 {
500     garray_T	*stack = &cctx->ctx_type_stack;
501 
502     RETURN_NULL_IF_SKIP(cctx);
503     stack->ga_len -= drop;
504     return generate_instr(cctx, isn_type);
505 }
506 
507 /*
508  * Generate instruction "isn_type" and put "type" on the type stack.
509  */
510     static isn_T *
511 generate_instr_type(cctx_T *cctx, isntype_T isn_type, type_T *type)
512 {
513     isn_T	*isn;
514     garray_T	*stack = &cctx->ctx_type_stack;
515 
516     if ((isn = generate_instr(cctx, isn_type)) == NULL)
517 	return NULL;
518 
519     if (ga_grow(stack, 1) == FAIL)
520 	return NULL;
521     ((type_T **)stack->ga_data)[stack->ga_len] = type == NULL ? &t_any : type;
522     ++stack->ga_len;
523 
524     return isn;
525 }
526 
527 /*
528  * If type at "offset" isn't already VAR_STRING then generate ISN_2STRING.
529  * But only for simple types.
530  */
531     static int
532 may_generate_2STRING(int offset, cctx_T *cctx)
533 {
534     isn_T	*isn;
535     isntype_T	isntype = ISN_2STRING;
536     garray_T	*stack = &cctx->ctx_type_stack;
537     type_T	**type;
538 
539     RETURN_OK_IF_SKIP(cctx);
540     type = ((type_T **)stack->ga_data) + stack->ga_len + offset;
541     switch ((*type)->tt_type)
542     {
543 	// nothing to be done
544 	case VAR_STRING: return OK;
545 
546 	// conversion possible
547 	case VAR_SPECIAL:
548 	case VAR_BOOL:
549 	case VAR_NUMBER:
550 	case VAR_FLOAT:
551 			 break;
552 
553 	// conversion possible (with runtime check)
554 	case VAR_ANY:
555 	case VAR_UNKNOWN:
556 			 isntype = ISN_2STRING_ANY;
557 			 break;
558 
559 	// conversion not possible
560 	case VAR_VOID:
561 	case VAR_BLOB:
562 	case VAR_FUNC:
563 	case VAR_PARTIAL:
564 	case VAR_LIST:
565 	case VAR_DICT:
566 	case VAR_JOB:
567 	case VAR_CHANNEL:
568 			 to_string_error((*type)->tt_type);
569 			 return FAIL;
570     }
571 
572     *type = &t_string;
573     if ((isn = generate_instr(cctx, isntype)) == NULL)
574 	return FAIL;
575     isn->isn_arg.number = offset;
576 
577     return OK;
578 }
579 
580     static int
581 check_number_or_float(vartype_T type1, vartype_T type2, char_u *op)
582 {
583     if (!((type1 == VAR_NUMBER || type1 == VAR_FLOAT || type1 == VAR_ANY)
584 	    && (type2 == VAR_NUMBER || type2 == VAR_FLOAT
585 							 || type2 == VAR_ANY)))
586     {
587 	if (*op == '+')
588 	    emsg(_(e_wrong_argument_type_for_plus));
589 	else
590 	    semsg(_(e_char_requires_number_or_float_arguments), *op);
591 	return FAIL;
592     }
593     return OK;
594 }
595 
596     static int
597 generate_add_instr(
598 	cctx_T *cctx,
599 	vartype_T vartype,
600 	type_T *type1,
601 	type_T *type2)
602 {
603     garray_T	*stack = &cctx->ctx_type_stack;
604     isn_T	*isn = generate_instr_drop(cctx,
605 		      vartype == VAR_NUMBER ? ISN_OPNR
606 		    : vartype == VAR_LIST ? ISN_ADDLIST
607 		    : vartype == VAR_BLOB ? ISN_ADDBLOB
608 #ifdef FEAT_FLOAT
609 		    : vartype == VAR_FLOAT ? ISN_OPFLOAT
610 #endif
611 		    : ISN_OPANY, 1);
612 
613     if (vartype != VAR_LIST && vartype != VAR_BLOB
614 	    && type1->tt_type != VAR_ANY
615 	    && type2->tt_type != VAR_ANY
616 	    && check_number_or_float(
617 			type1->tt_type, type2->tt_type, (char_u *)"+") == FAIL)
618 	return FAIL;
619 
620     if (isn != NULL)
621 	isn->isn_arg.op.op_type = EXPR_ADD;
622 
623     // When concatenating two lists with different member types the member type
624     // becomes "any".
625     if (vartype == VAR_LIST
626 	    && type1->tt_type == VAR_LIST && type2->tt_type == VAR_LIST
627 	    && type1->tt_member != type2->tt_member)
628 	(((type_T **)stack->ga_data)[stack->ga_len - 1]) = &t_list_any;
629 
630     return isn == NULL ? FAIL : OK;
631 }
632 
633 /*
634  * Get the type to use for an instruction for an operation on "type1" and
635  * "type2".  If they are matching use a type-specific instruction. Otherwise
636  * fall back to runtime type checking.
637  */
638     static vartype_T
639 operator_type(type_T *type1, type_T *type2)
640 {
641     if (type1->tt_type == type2->tt_type
642 	    && (type1->tt_type == VAR_NUMBER
643 		|| type1->tt_type == VAR_LIST
644 #ifdef FEAT_FLOAT
645 		|| type1->tt_type == VAR_FLOAT
646 #endif
647 		|| type1->tt_type == VAR_BLOB))
648 	return type1->tt_type;
649     return VAR_ANY;
650 }
651 
652 /*
653  * Generate an instruction with two arguments.  The instruction depends on the
654  * type of the arguments.
655  */
656     static int
657 generate_two_op(cctx_T *cctx, char_u *op)
658 {
659     garray_T	*stack = &cctx->ctx_type_stack;
660     type_T	*type1;
661     type_T	*type2;
662     vartype_T	vartype;
663     isn_T	*isn;
664 
665     RETURN_OK_IF_SKIP(cctx);
666 
667     // Get the known type of the two items on the stack.
668     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2];
669     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1];
670     vartype = operator_type(type1, type2);
671 
672     switch (*op)
673     {
674 	case '+':
675 		  if (generate_add_instr(cctx, vartype, type1, type2) == FAIL)
676 		      return FAIL;
677 		  break;
678 
679 	case '-':
680 	case '*':
681 	case '/': if (check_number_or_float(type1->tt_type, type2->tt_type,
682 								   op) == FAIL)
683 		      return FAIL;
684 		  if (vartype == VAR_NUMBER)
685 		      isn = generate_instr_drop(cctx, ISN_OPNR, 1);
686 #ifdef FEAT_FLOAT
687 		  else if (vartype == VAR_FLOAT)
688 		      isn = generate_instr_drop(cctx, ISN_OPFLOAT, 1);
689 #endif
690 		  else
691 		      isn = generate_instr_drop(cctx, ISN_OPANY, 1);
692 		  if (isn != NULL)
693 		      isn->isn_arg.op.op_type = *op == '*'
694 				 ? EXPR_MULT : *op == '/'? EXPR_DIV : EXPR_SUB;
695 		  break;
696 
697 	case '%': if ((type1->tt_type != VAR_ANY
698 					       && type1->tt_type != VAR_NUMBER)
699 			  || (type2->tt_type != VAR_ANY
700 					      && type2->tt_type != VAR_NUMBER))
701 		  {
702 		      emsg(_(e_percent_requires_number_arguments));
703 		      return FAIL;
704 		  }
705 		  isn = generate_instr_drop(cctx,
706 			      vartype == VAR_NUMBER ? ISN_OPNR : ISN_OPANY, 1);
707 		  if (isn != NULL)
708 		      isn->isn_arg.op.op_type = EXPR_REM;
709 		  break;
710     }
711 
712     // correct type of result
713     if (vartype == VAR_ANY)
714     {
715 	type_T *type = &t_any;
716 
717 #ifdef FEAT_FLOAT
718 	// float+number and number+float results in float
719 	if ((type1->tt_type == VAR_NUMBER || type1->tt_type == VAR_FLOAT)
720 		&& (type2->tt_type == VAR_NUMBER || type2->tt_type == VAR_FLOAT))
721 	    type = &t_float;
722 #endif
723 	((type_T **)stack->ga_data)[stack->ga_len - 1] = type;
724     }
725 
726     return OK;
727 }
728 
729 /*
730  * Get the instruction to use for comparing "type1" with "type2"
731  * Return ISN_DROP when failed.
732  */
733     static isntype_T
734 get_compare_isn(exprtype_T exprtype, vartype_T type1, vartype_T type2)
735 {
736     isntype_T	isntype = ISN_DROP;
737 
738     if (type1 == VAR_UNKNOWN)
739 	type1 = VAR_ANY;
740     if (type2 == VAR_UNKNOWN)
741 	type2 = VAR_ANY;
742 
743     if (type1 == type2)
744     {
745 	switch (type1)
746 	{
747 	    case VAR_BOOL: isntype = ISN_COMPAREBOOL; break;
748 	    case VAR_SPECIAL: isntype = ISN_COMPARESPECIAL; break;
749 	    case VAR_NUMBER: isntype = ISN_COMPARENR; break;
750 	    case VAR_FLOAT: isntype = ISN_COMPAREFLOAT; break;
751 	    case VAR_STRING: isntype = ISN_COMPARESTRING; break;
752 	    case VAR_BLOB: isntype = ISN_COMPAREBLOB; break;
753 	    case VAR_LIST: isntype = ISN_COMPARELIST; break;
754 	    case VAR_DICT: isntype = ISN_COMPAREDICT; break;
755 	    case VAR_FUNC: isntype = ISN_COMPAREFUNC; break;
756 	    default: isntype = ISN_COMPAREANY; break;
757 	}
758     }
759     else if (type1 == VAR_ANY || type2 == VAR_ANY
760 	    || ((type1 == VAR_NUMBER || type1 == VAR_FLOAT)
761 	      && (type2 == VAR_NUMBER || type2 == VAR_FLOAT)))
762 	isntype = ISN_COMPAREANY;
763 
764     if ((exprtype == EXPR_IS || exprtype == EXPR_ISNOT)
765 	    && (isntype == ISN_COMPAREBOOL
766 	    || isntype == ISN_COMPARESPECIAL
767 	    || isntype == ISN_COMPARENR
768 	    || isntype == ISN_COMPAREFLOAT))
769     {
770 	semsg(_(e_cannot_use_str_with_str),
771 		exprtype == EXPR_IS ? "is" : "isnot" , vartype_name(type1));
772 	return ISN_DROP;
773     }
774     if (isntype == ISN_DROP
775 	    || ((exprtype != EXPR_EQUAL && exprtype != EXPR_NEQUAL
776 		    && (type1 == VAR_BOOL || type1 == VAR_SPECIAL
777 		       || type2 == VAR_BOOL || type2 == VAR_SPECIAL)))
778 	    || ((exprtype != EXPR_EQUAL && exprtype != EXPR_NEQUAL
779 				 && exprtype != EXPR_IS && exprtype != EXPR_ISNOT
780 		    && (type1 == VAR_BLOB || type2 == VAR_BLOB
781 			|| type1 == VAR_LIST || type2 == VAR_LIST))))
782     {
783 	semsg(_(e_cannot_compare_str_with_str),
784 		vartype_name(type1), vartype_name(type2));
785 	return ISN_DROP;
786     }
787     return isntype;
788 }
789 
790     int
791 check_compare_types(exprtype_T type, typval_T *tv1, typval_T *tv2)
792 {
793     if (get_compare_isn(type, tv1->v_type, tv2->v_type) == ISN_DROP)
794 	return FAIL;
795     return OK;
796 }
797 
798 /*
799  * Generate an ISN_COMPARE* instruction with a boolean result.
800  */
801     static int
802 generate_COMPARE(cctx_T *cctx, exprtype_T exprtype, int ic)
803 {
804     isntype_T	isntype;
805     isn_T	*isn;
806     garray_T	*stack = &cctx->ctx_type_stack;
807     vartype_T	type1;
808     vartype_T	type2;
809 
810     RETURN_OK_IF_SKIP(cctx);
811 
812     // Get the known type of the two items on the stack.  If they are matching
813     // use a type-specific instruction. Otherwise fall back to runtime type
814     // checking.
815     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2]->tt_type;
816     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1]->tt_type;
817     isntype = get_compare_isn(exprtype, type1, type2);
818     if (isntype == ISN_DROP)
819 	return FAIL;
820 
821     if ((isn = generate_instr(cctx, isntype)) == NULL)
822 	return FAIL;
823     isn->isn_arg.op.op_type = exprtype;
824     isn->isn_arg.op.op_ic = ic;
825 
826     // takes two arguments, puts one bool back
827     if (stack->ga_len >= 2)
828     {
829 	--stack->ga_len;
830 	((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_bool;
831     }
832 
833     return OK;
834 }
835 
836 /*
837  * Generate an ISN_2BOOL instruction.
838  */
839     static int
840 generate_2BOOL(cctx_T *cctx, int invert)
841 {
842     isn_T	*isn;
843     garray_T	*stack = &cctx->ctx_type_stack;
844 
845     RETURN_OK_IF_SKIP(cctx);
846     if ((isn = generate_instr(cctx, ISN_2BOOL)) == NULL)
847 	return FAIL;
848     isn->isn_arg.number = invert;
849 
850     // type becomes bool
851     ((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_bool;
852 
853     return OK;
854 }
855 
856 /*
857  * Generate an ISN_COND2BOOL instruction.
858  */
859     static int
860 generate_COND2BOOL(cctx_T *cctx)
861 {
862     isn_T	*isn;
863     garray_T	*stack = &cctx->ctx_type_stack;
864 
865     RETURN_OK_IF_SKIP(cctx);
866     if ((isn = generate_instr(cctx, ISN_COND2BOOL)) == NULL)
867 	return FAIL;
868 
869     // type becomes bool
870     ((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_bool;
871 
872     return OK;
873 }
874 
875     static int
876 generate_TYPECHECK(
877 	cctx_T	    *cctx,
878 	type_T	    *expected,
879 	int	    offset,
880 	int	    argidx)
881 {
882     isn_T	*isn;
883     garray_T	*stack = &cctx->ctx_type_stack;
884 
885     RETURN_OK_IF_SKIP(cctx);
886     if ((isn = generate_instr(cctx, ISN_CHECKTYPE)) == NULL)
887 	return FAIL;
888     isn->isn_arg.type.ct_type = alloc_type(expected);
889     isn->isn_arg.type.ct_off = (int8_T)offset;
890     isn->isn_arg.type.ct_arg_idx = (int8_T)argidx;
891 
892     // type becomes expected
893     ((type_T **)stack->ga_data)[stack->ga_len + offset] = expected;
894 
895     return OK;
896 }
897 
898     static int
899 generate_SETTYPE(
900 	cctx_T	    *cctx,
901 	type_T	    *expected)
902 {
903     isn_T	*isn;
904 
905     RETURN_OK_IF_SKIP(cctx);
906     if ((isn = generate_instr(cctx, ISN_SETTYPE)) == NULL)
907 	return FAIL;
908     isn->isn_arg.type.ct_type = alloc_type(expected);
909     return OK;
910 }
911 
912 /*
913  * Return TRUE if "actual" could be "expected" and a runtime typecheck is to be
914  * used.  Return FALSE if the types will never match.
915  */
916     int
917 use_typecheck(type_T *actual, type_T *expected)
918 {
919     if (actual->tt_type == VAR_ANY
920 	    || actual->tt_type == VAR_UNKNOWN
921 	    || (actual->tt_type == VAR_FUNC
922 		&& (expected->tt_type == VAR_FUNC
923 					   || expected->tt_type == VAR_PARTIAL)
924 		&& (actual->tt_member == &t_any || actual->tt_argcount < 0)
925 		&& ((actual->tt_member == &t_void)
926 					 == (expected->tt_member == &t_void))))
927 	return TRUE;
928     if ((actual->tt_type == VAR_LIST || actual->tt_type == VAR_DICT)
929 				       && actual->tt_type == expected->tt_type)
930 	// This takes care of a nested list or dict.
931 	return use_typecheck(actual->tt_member, expected->tt_member);
932     return FALSE;
933 }
934 
935 /*
936  * Check that
937  * - "actual" matches "expected" type or
938  * - "actual" is a type that can be "expected" type: add a runtime check; or
939  * - return FAIL.
940  * If "actual_is_const" is TRUE then the type won't change at runtime, do not
941  * generate a TYPECHECK.
942  */
943     int
944 need_type(
945 	type_T	*actual,
946 	type_T	*expected,
947 	int	offset,
948 	int	arg_idx,
949 	cctx_T	*cctx,
950 	int	silent,
951 	int	actual_is_const)
952 {
953     where_T where;
954 
955     if (expected == &t_bool && actual != &t_bool
956 					&& (actual->tt_flags & TTFLAG_BOOL_OK))
957     {
958 	// Using "0", "1" or the result of an expression with "&&" or "||" as a
959 	// boolean is OK but requires a conversion.
960 	generate_2BOOL(cctx, FALSE);
961 	return OK;
962     }
963 
964     where.wt_index = arg_idx;
965     where.wt_variable = FALSE;
966     if (check_type(expected, actual, FALSE, where) == OK)
967 	return OK;
968 
969     // If the actual type can be the expected type add a runtime check.
970     // If it's a constant a runtime check makes no sense.
971     if (!actual_is_const && use_typecheck(actual, expected))
972     {
973 	generate_TYPECHECK(cctx, expected, offset, arg_idx);
974 	return OK;
975     }
976 
977     if (!silent)
978 	arg_type_mismatch(expected, actual, arg_idx);
979     return FAIL;
980 }
981 
982 /*
983  * Check that the top of the type stack has a type that can be used as a
984  * condition.  Give an error and return FAIL if not.
985  */
986     static int
987 bool_on_stack(cctx_T *cctx)
988 {
989     garray_T	*stack = &cctx->ctx_type_stack;
990     type_T	*type;
991 
992     type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
993     if (type == &t_bool)
994 	return OK;
995 
996     if (type == &t_any || type == &t_number)
997 	// Number 0 and 1 are OK to use as a bool.  "any" could also be a bool.
998 	// This requires a runtime type check.
999 	return generate_COND2BOOL(cctx);
1000 
1001     return need_type(type, &t_bool, -1, 0, cctx, FALSE, FALSE);
1002 }
1003 
1004 /*
1005  * Generate an ISN_PUSHNR instruction.
1006  */
1007     static int
1008 generate_PUSHNR(cctx_T *cctx, varnumber_T number)
1009 {
1010     isn_T	*isn;
1011     garray_T	*stack = &cctx->ctx_type_stack;
1012 
1013     RETURN_OK_IF_SKIP(cctx);
1014     if ((isn = generate_instr_type(cctx, ISN_PUSHNR, &t_number)) == NULL)
1015 	return FAIL;
1016     isn->isn_arg.number = number;
1017 
1018     if (number == 0 || number == 1)
1019 	// A 0 or 1 number can also be used as a bool.
1020 	((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_number_bool;
1021     return OK;
1022 }
1023 
1024 /*
1025  * Generate an ISN_PUSHBOOL instruction.
1026  */
1027     static int
1028 generate_PUSHBOOL(cctx_T *cctx, varnumber_T number)
1029 {
1030     isn_T	*isn;
1031 
1032     RETURN_OK_IF_SKIP(cctx);
1033     if ((isn = generate_instr_type(cctx, ISN_PUSHBOOL, &t_bool)) == NULL)
1034 	return FAIL;
1035     isn->isn_arg.number = number;
1036 
1037     return OK;
1038 }
1039 
1040 /*
1041  * Generate an ISN_PUSHSPEC instruction.
1042  */
1043     static int
1044 generate_PUSHSPEC(cctx_T *cctx, varnumber_T number)
1045 {
1046     isn_T	*isn;
1047 
1048     RETURN_OK_IF_SKIP(cctx);
1049     if ((isn = generate_instr_type(cctx, ISN_PUSHSPEC, &t_special)) == NULL)
1050 	return FAIL;
1051     isn->isn_arg.number = number;
1052 
1053     return OK;
1054 }
1055 
1056 #ifdef FEAT_FLOAT
1057 /*
1058  * Generate an ISN_PUSHF instruction.
1059  */
1060     static int
1061 generate_PUSHF(cctx_T *cctx, float_T fnumber)
1062 {
1063     isn_T	*isn;
1064 
1065     RETURN_OK_IF_SKIP(cctx);
1066     if ((isn = generate_instr_type(cctx, ISN_PUSHF, &t_float)) == NULL)
1067 	return FAIL;
1068     isn->isn_arg.fnumber = fnumber;
1069 
1070     return OK;
1071 }
1072 #endif
1073 
1074 /*
1075  * Generate an ISN_PUSHS instruction.
1076  * Consumes "str".
1077  */
1078     static int
1079 generate_PUSHS(cctx_T *cctx, char_u *str)
1080 {
1081     isn_T	*isn;
1082 
1083     if (cctx->ctx_skip == SKIP_YES)
1084     {
1085 	vim_free(str);
1086 	return OK;
1087     }
1088     if ((isn = generate_instr_type(cctx, ISN_PUSHS, &t_string)) == NULL)
1089 	return FAIL;
1090     isn->isn_arg.string = str;
1091 
1092     return OK;
1093 }
1094 
1095 /*
1096  * Generate an ISN_PUSHCHANNEL instruction.
1097  * Consumes "channel".
1098  */
1099     static int
1100 generate_PUSHCHANNEL(cctx_T *cctx, channel_T *channel)
1101 {
1102     isn_T	*isn;
1103 
1104     RETURN_OK_IF_SKIP(cctx);
1105     if ((isn = generate_instr_type(cctx, ISN_PUSHCHANNEL, &t_channel)) == NULL)
1106 	return FAIL;
1107     isn->isn_arg.channel = channel;
1108 
1109     return OK;
1110 }
1111 
1112 /*
1113  * Generate an ISN_PUSHJOB instruction.
1114  * Consumes "job".
1115  */
1116     static int
1117 generate_PUSHJOB(cctx_T *cctx, job_T *job)
1118 {
1119     isn_T	*isn;
1120 
1121     RETURN_OK_IF_SKIP(cctx);
1122     if ((isn = generate_instr_type(cctx, ISN_PUSHJOB, &t_channel)) == NULL)
1123 	return FAIL;
1124     isn->isn_arg.job = job;
1125 
1126     return OK;
1127 }
1128 
1129 /*
1130  * Generate an ISN_PUSHBLOB instruction.
1131  * Consumes "blob".
1132  */
1133     static int
1134 generate_PUSHBLOB(cctx_T *cctx, blob_T *blob)
1135 {
1136     isn_T	*isn;
1137 
1138     RETURN_OK_IF_SKIP(cctx);
1139     if ((isn = generate_instr_type(cctx, ISN_PUSHBLOB, &t_blob)) == NULL)
1140 	return FAIL;
1141     isn->isn_arg.blob = blob;
1142 
1143     return OK;
1144 }
1145 
1146 /*
1147  * Generate an ISN_PUSHFUNC instruction with name "name".
1148  * Consumes "name".
1149  */
1150     static int
1151 generate_PUSHFUNC(cctx_T *cctx, char_u *name, type_T *type)
1152 {
1153     isn_T	*isn;
1154 
1155     RETURN_OK_IF_SKIP(cctx);
1156     if ((isn = generate_instr_type(cctx, ISN_PUSHFUNC, type)) == NULL)
1157 	return FAIL;
1158     isn->isn_arg.string = name == NULL ? NULL : vim_strsave(name);
1159 
1160     return OK;
1161 }
1162 
1163 /*
1164  * Generate an ISN_GETITEM instruction with "index".
1165  */
1166     static int
1167 generate_GETITEM(cctx_T *cctx, int index)
1168 {
1169     isn_T	*isn;
1170     garray_T	*stack = &cctx->ctx_type_stack;
1171     type_T	*type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1172     type_T	*item_type = &t_any;
1173 
1174     RETURN_OK_IF_SKIP(cctx);
1175 
1176     if (type->tt_type != VAR_LIST)
1177     {
1178 	// cannot happen, caller has checked the type
1179 	emsg(_(e_listreq));
1180 	return FAIL;
1181     }
1182     item_type = type->tt_member;
1183     if ((isn = generate_instr(cctx, ISN_GETITEM)) == NULL)
1184 	return FAIL;
1185     isn->isn_arg.number = index;
1186 
1187     // add the item type to the type stack
1188     if (ga_grow(stack, 1) == FAIL)
1189 	return FAIL;
1190     ((type_T **)stack->ga_data)[stack->ga_len] = item_type;
1191     ++stack->ga_len;
1192     return OK;
1193 }
1194 
1195 /*
1196  * Generate an ISN_SLICE instruction with "count".
1197  */
1198     static int
1199 generate_SLICE(cctx_T *cctx, int count)
1200 {
1201     isn_T	*isn;
1202 
1203     RETURN_OK_IF_SKIP(cctx);
1204     if ((isn = generate_instr(cctx, ISN_SLICE)) == NULL)
1205 	return FAIL;
1206     isn->isn_arg.number = count;
1207     return OK;
1208 }
1209 
1210 /*
1211  * Generate an ISN_CHECKLEN instruction with "min_len".
1212  */
1213     static int
1214 generate_CHECKLEN(cctx_T *cctx, int min_len, int more_OK)
1215 {
1216     isn_T	*isn;
1217 
1218     RETURN_OK_IF_SKIP(cctx);
1219 
1220     if ((isn = generate_instr(cctx, ISN_CHECKLEN)) == NULL)
1221 	return FAIL;
1222     isn->isn_arg.checklen.cl_min_len = min_len;
1223     isn->isn_arg.checklen.cl_more_OK = more_OK;
1224 
1225     return OK;
1226 }
1227 
1228 /*
1229  * Generate an ISN_STORE instruction.
1230  */
1231     static int
1232 generate_STORE(cctx_T *cctx, isntype_T isn_type, int idx, char_u *name)
1233 {
1234     isn_T	*isn;
1235 
1236     RETURN_OK_IF_SKIP(cctx);
1237     if ((isn = generate_instr_drop(cctx, isn_type, 1)) == NULL)
1238 	return FAIL;
1239     if (name != NULL)
1240 	isn->isn_arg.string = vim_strsave(name);
1241     else
1242 	isn->isn_arg.number = idx;
1243 
1244     return OK;
1245 }
1246 
1247 /*
1248  * Generate an ISN_STOREOUTER instruction.
1249  */
1250     static int
1251 generate_STOREOUTER(cctx_T *cctx, int idx, int level)
1252 {
1253     isn_T	*isn;
1254 
1255     RETURN_OK_IF_SKIP(cctx);
1256     if ((isn = generate_instr_drop(cctx, ISN_STOREOUTER, 1)) == NULL)
1257 	return FAIL;
1258     isn->isn_arg.outer.outer_idx = idx;
1259     isn->isn_arg.outer.outer_depth = level;
1260 
1261     return OK;
1262 }
1263 
1264 /*
1265  * Generate an ISN_STORENR instruction (short for ISN_PUSHNR + ISN_STORE)
1266  */
1267     static int
1268 generate_STORENR(cctx_T *cctx, int idx, varnumber_T value)
1269 {
1270     isn_T	*isn;
1271 
1272     RETURN_OK_IF_SKIP(cctx);
1273     if ((isn = generate_instr(cctx, ISN_STORENR)) == NULL)
1274 	return FAIL;
1275     isn->isn_arg.storenr.stnr_idx = idx;
1276     isn->isn_arg.storenr.stnr_val = value;
1277 
1278     return OK;
1279 }
1280 
1281 /*
1282  * Generate an ISN_STOREOPT instruction
1283  */
1284     static int
1285 generate_STOREOPT(cctx_T *cctx, char_u *name, int opt_flags)
1286 {
1287     isn_T	*isn;
1288 
1289     RETURN_OK_IF_SKIP(cctx);
1290     if ((isn = generate_instr_drop(cctx, ISN_STOREOPT, 1)) == NULL)
1291 	return FAIL;
1292     isn->isn_arg.storeopt.so_name = vim_strsave(name);
1293     isn->isn_arg.storeopt.so_flags = opt_flags;
1294 
1295     return OK;
1296 }
1297 
1298 /*
1299  * Generate an ISN_LOAD or similar instruction.
1300  */
1301     static int
1302 generate_LOAD(
1303 	cctx_T	    *cctx,
1304 	isntype_T   isn_type,
1305 	int	    idx,
1306 	char_u	    *name,
1307 	type_T	    *type)
1308 {
1309     isn_T	*isn;
1310 
1311     RETURN_OK_IF_SKIP(cctx);
1312     if ((isn = generate_instr_type(cctx, isn_type, type)) == NULL)
1313 	return FAIL;
1314     if (name != NULL)
1315 	isn->isn_arg.string = vim_strsave(name);
1316     else
1317 	isn->isn_arg.number = idx;
1318 
1319     return OK;
1320 }
1321 
1322 /*
1323  * Generate an ISN_LOADOUTER instruction
1324  */
1325     static int
1326 generate_LOADOUTER(
1327 	cctx_T	    *cctx,
1328 	int	    idx,
1329 	int	    nesting,
1330 	type_T	    *type)
1331 {
1332     isn_T	*isn;
1333 
1334     RETURN_OK_IF_SKIP(cctx);
1335     if ((isn = generate_instr_type(cctx, ISN_LOADOUTER, type)) == NULL)
1336 	return FAIL;
1337     isn->isn_arg.outer.outer_idx = idx;
1338     isn->isn_arg.outer.outer_depth = nesting;
1339 
1340     return OK;
1341 }
1342 
1343 /*
1344  * Generate an ISN_LOADV instruction for v:var.
1345  */
1346     static int
1347 generate_LOADV(
1348 	cctx_T	    *cctx,
1349 	char_u	    *name,
1350 	int	    error)
1351 {
1352     int	    di_flags;
1353     int	    vidx = find_vim_var(name, &di_flags);
1354     type_T  *type;
1355 
1356     RETURN_OK_IF_SKIP(cctx);
1357     if (vidx < 0)
1358     {
1359 	if (error)
1360 	    semsg(_(e_variable_not_found_str), name);
1361 	return FAIL;
1362     }
1363     type = typval2type_vimvar(get_vim_var_tv(vidx), cctx->ctx_type_list);
1364 
1365     return generate_LOAD(cctx, ISN_LOADV, vidx, NULL, type);
1366 }
1367 
1368 /*
1369  * Generate an ISN_UNLET instruction.
1370  */
1371     static int
1372 generate_UNLET(cctx_T *cctx, isntype_T isn_type, char_u *name, int forceit)
1373 {
1374     isn_T	*isn;
1375 
1376     RETURN_OK_IF_SKIP(cctx);
1377     if ((isn = generate_instr(cctx, isn_type)) == NULL)
1378 	return FAIL;
1379     isn->isn_arg.unlet.ul_name = vim_strsave(name);
1380     isn->isn_arg.unlet.ul_forceit = forceit;
1381 
1382     return OK;
1383 }
1384 
1385 /*
1386  * Generate an ISN_LOCKCONST instruction.
1387  */
1388     static int
1389 generate_LOCKCONST(cctx_T *cctx)
1390 {
1391     isn_T	*isn;
1392 
1393     RETURN_OK_IF_SKIP(cctx);
1394     if ((isn = generate_instr(cctx, ISN_LOCKCONST)) == NULL)
1395 	return FAIL;
1396     return OK;
1397 }
1398 
1399 /*
1400  * Generate an ISN_LOADS instruction.
1401  */
1402     static int
1403 generate_OLDSCRIPT(
1404 	cctx_T	    *cctx,
1405 	isntype_T   isn_type,
1406 	char_u	    *name,
1407 	int	    sid,
1408 	type_T	    *type)
1409 {
1410     isn_T	*isn;
1411 
1412     RETURN_OK_IF_SKIP(cctx);
1413     if (isn_type == ISN_LOADS)
1414 	isn = generate_instr_type(cctx, isn_type, type);
1415     else
1416 	isn = generate_instr_drop(cctx, isn_type, 1);
1417     if (isn == NULL)
1418 	return FAIL;
1419     isn->isn_arg.loadstore.ls_name = vim_strsave(name);
1420     isn->isn_arg.loadstore.ls_sid = sid;
1421 
1422     return OK;
1423 }
1424 
1425 /*
1426  * Generate an ISN_LOADSCRIPT or ISN_STORESCRIPT instruction.
1427  */
1428     static int
1429 generate_VIM9SCRIPT(
1430 	cctx_T	    *cctx,
1431 	isntype_T   isn_type,
1432 	int	    sid,
1433 	int	    idx,
1434 	type_T	    *type)
1435 {
1436     isn_T	*isn;
1437     scriptref_T	*sref;
1438     scriptitem_T *si = SCRIPT_ITEM(sid);
1439 
1440     RETURN_OK_IF_SKIP(cctx);
1441     if (isn_type == ISN_LOADSCRIPT)
1442 	isn = generate_instr_type(cctx, isn_type, type);
1443     else
1444 	isn = generate_instr_drop(cctx, isn_type, 1);
1445     if (isn == NULL)
1446 	return FAIL;
1447 
1448     // This requires three arguments, which doesn't fit in an instruction, thus
1449     // we need to allocate a struct for this.
1450     sref = ALLOC_ONE(scriptref_T);
1451     if (sref == NULL)
1452 	return FAIL;
1453     isn->isn_arg.script.scriptref = sref;
1454     sref->sref_sid = sid;
1455     sref->sref_idx = idx;
1456     sref->sref_seq = si->sn_script_seq;
1457     sref->sref_type = type;
1458     return OK;
1459 }
1460 
1461 /*
1462  * Generate an ISN_NEWLIST instruction.
1463  */
1464     static int
1465 generate_NEWLIST(cctx_T *cctx, int count)
1466 {
1467     isn_T	*isn;
1468     garray_T	*stack = &cctx->ctx_type_stack;
1469     type_T	*type;
1470     type_T	*member;
1471 
1472     RETURN_OK_IF_SKIP(cctx);
1473     if ((isn = generate_instr(cctx, ISN_NEWLIST)) == NULL)
1474 	return FAIL;
1475     isn->isn_arg.number = count;
1476 
1477     // get the member type from all the items on the stack.
1478     if (count == 0)
1479 	member = &t_void;
1480     else
1481 	member = get_member_type_from_stack(
1482 	    ((type_T **)stack->ga_data) + stack->ga_len, count, 1,
1483 							  cctx->ctx_type_list);
1484     type = get_list_type(member, cctx->ctx_type_list);
1485 
1486     // drop the value types
1487     stack->ga_len -= count;
1488 
1489     // add the list type to the type stack
1490     if (ga_grow(stack, 1) == FAIL)
1491 	return FAIL;
1492     ((type_T **)stack->ga_data)[stack->ga_len] = type;
1493     ++stack->ga_len;
1494 
1495     return OK;
1496 }
1497 
1498 /*
1499  * Generate an ISN_NEWDICT instruction.
1500  */
1501     static int
1502 generate_NEWDICT(cctx_T *cctx, int count)
1503 {
1504     isn_T	*isn;
1505     garray_T	*stack = &cctx->ctx_type_stack;
1506     type_T	*type;
1507     type_T	*member;
1508 
1509     RETURN_OK_IF_SKIP(cctx);
1510     if ((isn = generate_instr(cctx, ISN_NEWDICT)) == NULL)
1511 	return FAIL;
1512     isn->isn_arg.number = count;
1513 
1514     if (count == 0)
1515 	member = &t_void;
1516     else
1517 	member = get_member_type_from_stack(
1518 	    ((type_T **)stack->ga_data) + stack->ga_len, count, 2,
1519 							  cctx->ctx_type_list);
1520     type = get_dict_type(member, cctx->ctx_type_list);
1521 
1522     // drop the key and value types
1523     stack->ga_len -= 2 * count;
1524 
1525     // add the dict type to the type stack
1526     if (ga_grow(stack, 1) == FAIL)
1527 	return FAIL;
1528     ((type_T **)stack->ga_data)[stack->ga_len] = type;
1529     ++stack->ga_len;
1530 
1531     return OK;
1532 }
1533 
1534 /*
1535  * Generate an ISN_FUNCREF instruction.
1536  */
1537     static int
1538 generate_FUNCREF(cctx_T *cctx, ufunc_T *ufunc)
1539 {
1540     isn_T	*isn;
1541     garray_T	*stack = &cctx->ctx_type_stack;
1542 
1543     RETURN_OK_IF_SKIP(cctx);
1544     if ((isn = generate_instr(cctx, ISN_FUNCREF)) == NULL)
1545 	return FAIL;
1546     isn->isn_arg.funcref.fr_func = ufunc->uf_dfunc_idx;
1547     cctx->ctx_has_closure = 1;
1548 
1549     // If the referenced function is a closure, it may use items further up in
1550     // the nested context, including this one.
1551     if (ufunc->uf_flags & FC_CLOSURE)
1552 	cctx->ctx_ufunc->uf_flags |= FC_CLOSURE;
1553 
1554     if (ga_grow(stack, 1) == FAIL)
1555 	return FAIL;
1556     ((type_T **)stack->ga_data)[stack->ga_len] =
1557 	       ufunc->uf_func_type == NULL ? &t_func_any : ufunc->uf_func_type;
1558     ++stack->ga_len;
1559 
1560     return OK;
1561 }
1562 
1563 /*
1564  * Generate an ISN_NEWFUNC instruction.
1565  * "lambda_name" and "func_name" must be in allocated memory and will be
1566  * consumed.
1567  */
1568     static int
1569 generate_NEWFUNC(cctx_T *cctx, char_u *lambda_name, char_u *func_name)
1570 {
1571     isn_T	*isn;
1572 
1573     if (cctx->ctx_skip == SKIP_YES)
1574     {
1575 	vim_free(lambda_name);
1576 	vim_free(func_name);
1577 	return OK;
1578     }
1579     if ((isn = generate_instr(cctx, ISN_NEWFUNC)) == NULL)
1580     {
1581 	vim_free(lambda_name);
1582 	vim_free(func_name);
1583 	return FAIL;
1584     }
1585     isn->isn_arg.newfunc.nf_lambda = lambda_name;
1586     isn->isn_arg.newfunc.nf_global = func_name;
1587 
1588     return OK;
1589 }
1590 
1591 /*
1592  * Generate an ISN_DEF instruction: list functions
1593  */
1594     static int
1595 generate_DEF(cctx_T *cctx, char_u *name, size_t len)
1596 {
1597     isn_T	*isn;
1598 
1599     RETURN_OK_IF_SKIP(cctx);
1600     if ((isn = generate_instr(cctx, ISN_DEF)) == NULL)
1601 	return FAIL;
1602     if (len > 0)
1603     {
1604 	isn->isn_arg.string = vim_strnsave(name, len);
1605 	if (isn->isn_arg.string == NULL)
1606 	    return FAIL;
1607     }
1608     return OK;
1609 }
1610 
1611 /*
1612  * Generate an ISN_JUMP instruction.
1613  */
1614     static int
1615 generate_JUMP(cctx_T *cctx, jumpwhen_T when, int where)
1616 {
1617     isn_T	*isn;
1618     garray_T	*stack = &cctx->ctx_type_stack;
1619 
1620     RETURN_OK_IF_SKIP(cctx);
1621     if ((isn = generate_instr(cctx, ISN_JUMP)) == NULL)
1622 	return FAIL;
1623     isn->isn_arg.jump.jump_when = when;
1624     isn->isn_arg.jump.jump_where = where;
1625 
1626     if (when != JUMP_ALWAYS && stack->ga_len > 0)
1627 	--stack->ga_len;
1628 
1629     return OK;
1630 }
1631 
1632 /*
1633  * Generate an ISN_JUMP_IF_ARG_SET instruction.
1634  */
1635     static int
1636 generate_JUMP_IF_ARG_SET(cctx_T *cctx, int arg_off)
1637 {
1638     isn_T	*isn;
1639 
1640     RETURN_OK_IF_SKIP(cctx);
1641     if ((isn = generate_instr(cctx, ISN_JUMP_IF_ARG_SET)) == NULL)
1642 	return FAIL;
1643     isn->isn_arg.jumparg.jump_arg_off = arg_off;
1644     // jump_where is set later
1645     return OK;
1646 }
1647 
1648     static int
1649 generate_FOR(cctx_T *cctx, int loop_idx)
1650 {
1651     isn_T	*isn;
1652     garray_T	*stack = &cctx->ctx_type_stack;
1653 
1654     RETURN_OK_IF_SKIP(cctx);
1655     if ((isn = generate_instr(cctx, ISN_FOR)) == NULL)
1656 	return FAIL;
1657     isn->isn_arg.forloop.for_idx = loop_idx;
1658 
1659     if (ga_grow(stack, 1) == FAIL)
1660 	return FAIL;
1661     // type doesn't matter, will be stored next
1662     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
1663     ++stack->ga_len;
1664 
1665     return OK;
1666 }
1667 /*
1668  * Generate an ISN_TRYCONT instruction.
1669  */
1670     static int
1671 generate_TRYCONT(cctx_T *cctx, int levels, int where)
1672 {
1673     isn_T	*isn;
1674 
1675     RETURN_OK_IF_SKIP(cctx);
1676     if ((isn = generate_instr(cctx, ISN_TRYCONT)) == NULL)
1677 	return FAIL;
1678     isn->isn_arg.trycont.tct_levels = levels;
1679     isn->isn_arg.trycont.tct_where = where;
1680 
1681     return OK;
1682 }
1683 
1684 
1685 /*
1686  * Generate an ISN_BCALL instruction.
1687  * "method_call" is TRUE for "value->method()"
1688  * Return FAIL if the number of arguments is wrong.
1689  */
1690     static int
1691 generate_BCALL(cctx_T *cctx, int func_idx, int argcount, int method_call)
1692 {
1693     isn_T	*isn;
1694     garray_T	*stack = &cctx->ctx_type_stack;
1695     int		argoff;
1696     type_T	**argtypes = NULL;
1697     type_T	*maptype = NULL;
1698 
1699     RETURN_OK_IF_SKIP(cctx);
1700     argoff = check_internal_func(func_idx, argcount);
1701     if (argoff < 0)
1702 	return FAIL;
1703 
1704     if (method_call && argoff > 1)
1705     {
1706 	if ((isn = generate_instr(cctx, ISN_SHUFFLE)) == NULL)
1707 	    return FAIL;
1708 	isn->isn_arg.shuffle.shfl_item = argcount;
1709 	isn->isn_arg.shuffle.shfl_up = argoff - 1;
1710     }
1711 
1712     if (argcount > 0)
1713     {
1714 	// Check the types of the arguments.
1715 	argtypes = ((type_T **)stack->ga_data) + stack->ga_len - argcount;
1716 	if (internal_func_check_arg_types(argtypes, func_idx, argcount,
1717 								 cctx) == FAIL)
1718 	    return FAIL;
1719 	if (internal_func_is_map(func_idx))
1720 	    maptype = *argtypes;
1721     }
1722 
1723     if ((isn = generate_instr(cctx, ISN_BCALL)) == NULL)
1724 	return FAIL;
1725     isn->isn_arg.bfunc.cbf_idx = func_idx;
1726     isn->isn_arg.bfunc.cbf_argcount = argcount;
1727 
1728     // Drop the argument types and push the return type.
1729     stack->ga_len -= argcount;
1730     if (ga_grow(stack, 1) == FAIL)
1731 	return FAIL;
1732     ((type_T **)stack->ga_data)[stack->ga_len] =
1733 			  internal_func_ret_type(func_idx, argcount, argtypes);
1734     ++stack->ga_len;
1735 
1736     if (maptype != NULL && maptype->tt_member != NULL
1737 					       && maptype->tt_member != &t_any)
1738 	// Check that map() didn't change the item types.
1739 	generate_TYPECHECK(cctx, maptype, -1, 1);
1740 
1741     return OK;
1742 }
1743 
1744 /*
1745  * Generate an ISN_LISTAPPEND instruction.  Works like add().
1746  * Argument count is already checked.
1747  */
1748     static int
1749 generate_LISTAPPEND(cctx_T *cctx)
1750 {
1751     garray_T	*stack = &cctx->ctx_type_stack;
1752     type_T	*list_type;
1753     type_T	*item_type;
1754     type_T	*expected;
1755 
1756     // Caller already checked that list_type is a list.
1757     list_type = ((type_T **)stack->ga_data)[stack->ga_len - 2];
1758     item_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1759     expected = list_type->tt_member;
1760     if (need_type(item_type, expected, -1, 0, cctx, FALSE, FALSE) == FAIL)
1761 	return FAIL;
1762 
1763     if (generate_instr(cctx, ISN_LISTAPPEND) == NULL)
1764 	return FAIL;
1765 
1766     --stack->ga_len;	    // drop the argument
1767     return OK;
1768 }
1769 
1770 /*
1771  * Generate an ISN_BLOBAPPEND instruction.  Works like add().
1772  * Argument count is already checked.
1773  */
1774     static int
1775 generate_BLOBAPPEND(cctx_T *cctx)
1776 {
1777     garray_T	*stack = &cctx->ctx_type_stack;
1778     type_T	*item_type;
1779 
1780     // Caller already checked that blob_type is a blob.
1781     item_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1782     if (need_type(item_type, &t_number, -1, 0, cctx, FALSE, FALSE) == FAIL)
1783 	return FAIL;
1784 
1785     if (generate_instr(cctx, ISN_BLOBAPPEND) == NULL)
1786 	return FAIL;
1787 
1788     --stack->ga_len;	    // drop the argument
1789     return OK;
1790 }
1791 
1792 /*
1793  * Return TRUE if "ufunc" should be compiled, taking into account whether
1794  * "profile" indicates profiling is to be done.
1795  */
1796     int
1797 func_needs_compiling(ufunc_T *ufunc, int profile UNUSED)
1798 {
1799     switch (ufunc->uf_def_status)
1800     {
1801 	case UF_NOT_COMPILED: break;
1802 	case UF_TO_BE_COMPILED: return TRUE;
1803 	case UF_COMPILED:
1804 	{
1805 #ifdef FEAT_PROFILE
1806 	    dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
1807 							 + ufunc->uf_dfunc_idx;
1808 
1809 	    return profile ? dfunc->df_instr_prof == NULL
1810 			   : dfunc->df_instr == NULL;
1811 #else
1812 	    break;
1813 #endif
1814 	}
1815 	case UF_COMPILING: break;
1816     }
1817     return FALSE;
1818 }
1819 
1820 /*
1821  * Generate an ISN_DCALL or ISN_UCALL instruction.
1822  * Return FAIL if the number of arguments is wrong.
1823  */
1824     static int
1825 generate_CALL(cctx_T *cctx, ufunc_T *ufunc, int pushed_argcount)
1826 {
1827     isn_T	*isn;
1828     garray_T	*stack = &cctx->ctx_type_stack;
1829     int		regular_args = ufunc->uf_args.ga_len;
1830     int		argcount = pushed_argcount;
1831 
1832     RETURN_OK_IF_SKIP(cctx);
1833     if (argcount > regular_args && !has_varargs(ufunc))
1834     {
1835 	semsg(_(e_toomanyarg), printable_func_name(ufunc));
1836 	return FAIL;
1837     }
1838     if (argcount < regular_args - ufunc->uf_def_args.ga_len)
1839     {
1840 	semsg(_(e_toofewarg), printable_func_name(ufunc));
1841 	return FAIL;
1842     }
1843 
1844     if (ufunc->uf_def_status != UF_NOT_COMPILED)
1845     {
1846 	int		i;
1847 
1848 	for (i = 0; i < argcount; ++i)
1849 	{
1850 	    type_T *expected;
1851 	    type_T *actual;
1852 
1853 	    actual = ((type_T **)stack->ga_data)[stack->ga_len - argcount + i];
1854 	    if (actual == &t_special
1855 			      && i >= regular_args - ufunc->uf_def_args.ga_len)
1856 	    {
1857 		// assume v:none used for default argument value
1858 		continue;
1859 	    }
1860 	    if (i < regular_args)
1861 	    {
1862 		if (ufunc->uf_arg_types == NULL)
1863 		    continue;
1864 		expected = ufunc->uf_arg_types[i];
1865 	    }
1866 	    else if (ufunc->uf_va_type == NULL || ufunc->uf_va_type == &t_any)
1867 		// possibly a lambda or "...: any"
1868 		expected = &t_any;
1869 	    else
1870 		expected = ufunc->uf_va_type->tt_member;
1871 	    if (need_type(actual, expected, -argcount + i, i + 1, cctx,
1872 							  TRUE, FALSE) == FAIL)
1873 	    {
1874 		arg_type_mismatch(expected, actual, i + 1);
1875 		return FAIL;
1876 	    }
1877 	}
1878 	if (func_needs_compiling(ufunc, PROFILING(ufunc))
1879 		&& compile_def_function(ufunc, ufunc->uf_ret_type == NULL,
1880 					       PROFILING(ufunc), NULL) == FAIL)
1881 	    return FAIL;
1882     }
1883 
1884     if ((isn = generate_instr(cctx,
1885 		    ufunc->uf_def_status != UF_NOT_COMPILED ? ISN_DCALL
1886 							 : ISN_UCALL)) == NULL)
1887 	return FAIL;
1888     if (isn->isn_type == ISN_DCALL)
1889     {
1890 	isn->isn_arg.dfunc.cdf_idx = ufunc->uf_dfunc_idx;
1891 	isn->isn_arg.dfunc.cdf_argcount = argcount;
1892     }
1893     else
1894     {
1895 	// A user function may be deleted and redefined later, can't use the
1896 	// ufunc pointer, need to look it up again at runtime.
1897 	isn->isn_arg.ufunc.cuf_name = vim_strsave(ufunc->uf_name);
1898 	isn->isn_arg.ufunc.cuf_argcount = argcount;
1899     }
1900 
1901     stack->ga_len -= argcount; // drop the arguments
1902     if (ga_grow(stack, 1) == FAIL)
1903 	return FAIL;
1904     // add return value
1905     ((type_T **)stack->ga_data)[stack->ga_len] = ufunc->uf_ret_type;
1906     ++stack->ga_len;
1907 
1908     return OK;
1909 }
1910 
1911 /*
1912  * Generate an ISN_UCALL instruction when the function isn't defined yet.
1913  */
1914     static int
1915 generate_UCALL(cctx_T *cctx, char_u *name, int argcount)
1916 {
1917     isn_T	*isn;
1918     garray_T	*stack = &cctx->ctx_type_stack;
1919 
1920     RETURN_OK_IF_SKIP(cctx);
1921     if ((isn = generate_instr(cctx, ISN_UCALL)) == NULL)
1922 	return FAIL;
1923     isn->isn_arg.ufunc.cuf_name = vim_strsave(name);
1924     isn->isn_arg.ufunc.cuf_argcount = argcount;
1925 
1926     stack->ga_len -= argcount; // drop the arguments
1927     if (ga_grow(stack, 1) == FAIL)
1928 	return FAIL;
1929     // add return value
1930     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
1931     ++stack->ga_len;
1932 
1933     return OK;
1934 }
1935 
1936 /*
1937  * Generate an ISN_PCALL instruction.
1938  * "type" is the type of the FuncRef.
1939  */
1940     static int
1941 generate_PCALL(
1942 	cctx_T	*cctx,
1943 	int	argcount,
1944 	char_u	*name,
1945 	type_T	*type,
1946 	int	at_top)
1947 {
1948     isn_T	*isn;
1949     garray_T	*stack = &cctx->ctx_type_stack;
1950     type_T	*ret_type;
1951 
1952     RETURN_OK_IF_SKIP(cctx);
1953 
1954     if (type->tt_type == VAR_ANY)
1955 	ret_type = &t_any;
1956     else if (type->tt_type == VAR_FUNC || type->tt_type == VAR_PARTIAL)
1957     {
1958 	if (type->tt_argcount != -1)
1959 	{
1960 	    int	    varargs = (type->tt_flags & TTFLAG_VARARGS) ? 1 : 0;
1961 
1962 	    if (argcount < type->tt_min_argcount - varargs)
1963 	    {
1964 		semsg(_(e_toofewarg), name);
1965 		return FAIL;
1966 	    }
1967 	    if (!varargs && argcount > type->tt_argcount)
1968 	    {
1969 		semsg(_(e_toomanyarg), name);
1970 		return FAIL;
1971 	    }
1972 	    if (type->tt_args != NULL)
1973 	    {
1974 		int i;
1975 
1976 		for (i = 0; i < argcount; ++i)
1977 		{
1978 		    int	    offset = -argcount + i - 1;
1979 		    type_T *actual = ((type_T **)stack->ga_data)[
1980 						       stack->ga_len + offset];
1981 		    type_T *expected;
1982 
1983 		    if (varargs && i >= type->tt_argcount - 1)
1984 			expected = type->tt_args[
1985 					     type->tt_argcount - 1]->tt_member;
1986 		    else if (i >= type->tt_min_argcount
1987 						       && actual == &t_special)
1988 			expected = &t_any;
1989 		    else
1990 			expected = type->tt_args[i];
1991 		    if (need_type(actual, expected, offset, i + 1,
1992 						    cctx, TRUE, FALSE) == FAIL)
1993 		    {
1994 			arg_type_mismatch(expected, actual, i + 1);
1995 			return FAIL;
1996 		    }
1997 		}
1998 	    }
1999 	}
2000 	ret_type = type->tt_member;
2001     }
2002     else
2003     {
2004 	semsg(_(e_not_callable_type_str), name);
2005 	return FAIL;
2006     }
2007 
2008     if ((isn = generate_instr(cctx, ISN_PCALL)) == NULL)
2009 	return FAIL;
2010     isn->isn_arg.pfunc.cpf_top = at_top;
2011     isn->isn_arg.pfunc.cpf_argcount = argcount;
2012 
2013     stack->ga_len -= argcount; // drop the arguments
2014 
2015     // drop the funcref/partial, get back the return value
2016     ((type_T **)stack->ga_data)[stack->ga_len - 1] = ret_type;
2017 
2018     // If partial is above the arguments it must be cleared and replaced with
2019     // the return value.
2020     if (at_top && generate_instr(cctx, ISN_PCALL_END) == NULL)
2021 	return FAIL;
2022 
2023     return OK;
2024 }
2025 
2026 /*
2027  * Generate an ISN_STRINGMEMBER instruction.
2028  */
2029     static int
2030 generate_STRINGMEMBER(cctx_T *cctx, char_u *name, size_t len)
2031 {
2032     isn_T	*isn;
2033     garray_T	*stack = &cctx->ctx_type_stack;
2034     type_T	*type;
2035 
2036     RETURN_OK_IF_SKIP(cctx);
2037     if ((isn = generate_instr(cctx, ISN_STRINGMEMBER)) == NULL)
2038 	return FAIL;
2039     isn->isn_arg.string = vim_strnsave(name, len);
2040 
2041     // check for dict type
2042     type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
2043     if (type->tt_type != VAR_DICT && type != &t_any)
2044     {
2045 	emsg(_(e_dictreq));
2046 	return FAIL;
2047     }
2048     // change dict type to dict member type
2049     if (type->tt_type == VAR_DICT)
2050     {
2051 	((type_T **)stack->ga_data)[stack->ga_len - 1] =
2052 		      type->tt_member == &t_unknown ? &t_any : type->tt_member;
2053     }
2054 
2055     return OK;
2056 }
2057 
2058 /*
2059  * Generate an ISN_ECHO instruction.
2060  */
2061     static int
2062 generate_ECHO(cctx_T *cctx, int with_white, int count)
2063 {
2064     isn_T	*isn;
2065 
2066     RETURN_OK_IF_SKIP(cctx);
2067     if ((isn = generate_instr_drop(cctx, ISN_ECHO, count)) == NULL)
2068 	return FAIL;
2069     isn->isn_arg.echo.echo_with_white = with_white;
2070     isn->isn_arg.echo.echo_count = count;
2071 
2072     return OK;
2073 }
2074 
2075 /*
2076  * Generate an ISN_EXECUTE/ISN_ECHOMSG/ISN_ECHOERR instruction.
2077  */
2078     static int
2079 generate_MULT_EXPR(cctx_T *cctx, isntype_T isn_type, int count)
2080 {
2081     isn_T	*isn;
2082 
2083     if ((isn = generate_instr_drop(cctx, isn_type, count)) == NULL)
2084 	return FAIL;
2085     isn->isn_arg.number = count;
2086 
2087     return OK;
2088 }
2089 
2090 /*
2091  * Generate an ISN_PUT instruction.
2092  */
2093     static int
2094 generate_PUT(cctx_T *cctx, int regname, linenr_T lnum)
2095 {
2096     isn_T	*isn;
2097 
2098     RETURN_OK_IF_SKIP(cctx);
2099     if ((isn = generate_instr(cctx, ISN_PUT)) == NULL)
2100 	return FAIL;
2101     isn->isn_arg.put.put_regname = regname;
2102     isn->isn_arg.put.put_lnum = lnum;
2103     return OK;
2104 }
2105 
2106     static int
2107 generate_EXEC(cctx_T *cctx, char_u *line)
2108 {
2109     isn_T	*isn;
2110 
2111     RETURN_OK_IF_SKIP(cctx);
2112     if ((isn = generate_instr(cctx, ISN_EXEC)) == NULL)
2113 	return FAIL;
2114     isn->isn_arg.string = vim_strsave(line);
2115     return OK;
2116 }
2117 
2118     static int
2119 generate_EXECCONCAT(cctx_T *cctx, int count)
2120 {
2121     isn_T	*isn;
2122 
2123     if ((isn = generate_instr_drop(cctx, ISN_EXECCONCAT, count)) == NULL)
2124 	return FAIL;
2125     isn->isn_arg.number = count;
2126     return OK;
2127 }
2128 
2129 /*
2130  * Generate ISN_RANGE.  Consumes "range".  Return OK/FAIL.
2131  */
2132     static int
2133 generate_RANGE(cctx_T *cctx, char_u *range)
2134 {
2135     isn_T	*isn;
2136     garray_T	*stack = &cctx->ctx_type_stack;
2137 
2138     if ((isn = generate_instr(cctx, ISN_RANGE)) == NULL)
2139 	return FAIL;
2140     isn->isn_arg.string = range;
2141 
2142     if (ga_grow(stack, 1) == FAIL)
2143 	return FAIL;
2144     ((type_T **)stack->ga_data)[stack->ga_len] = &t_number;
2145     ++stack->ga_len;
2146     return OK;
2147 }
2148 
2149     static int
2150 generate_UNPACK(cctx_T *cctx, int var_count, int semicolon)
2151 {
2152     isn_T	*isn;
2153 
2154     RETURN_OK_IF_SKIP(cctx);
2155     if ((isn = generate_instr(cctx, ISN_UNPACK)) == NULL)
2156 	return FAIL;
2157     isn->isn_arg.unpack.unp_count = var_count;
2158     isn->isn_arg.unpack.unp_semicolon = semicolon;
2159     return OK;
2160 }
2161 
2162 /*
2163  * Generate an instruction for any command modifiers.
2164  */
2165     static int
2166 generate_cmdmods(cctx_T *cctx, cmdmod_T *cmod)
2167 {
2168     isn_T	*isn;
2169 
2170     if (has_cmdmod(cmod))
2171     {
2172 	cctx->ctx_has_cmdmod = TRUE;
2173 
2174 	if ((isn = generate_instr(cctx, ISN_CMDMOD)) == NULL)
2175 	    return FAIL;
2176 	isn->isn_arg.cmdmod.cf_cmdmod = ALLOC_ONE(cmdmod_T);
2177 	if (isn->isn_arg.cmdmod.cf_cmdmod == NULL)
2178 	    return FAIL;
2179 	mch_memmove(isn->isn_arg.cmdmod.cf_cmdmod, cmod, sizeof(cmdmod_T));
2180 	// filter program now belongs to the instruction
2181 	cmod->cmod_filter_regmatch.regprog = NULL;
2182     }
2183 
2184     return OK;
2185 }
2186 
2187     static int
2188 generate_undo_cmdmods(cctx_T *cctx)
2189 {
2190     if (cctx->ctx_has_cmdmod && generate_instr(cctx, ISN_CMDMOD_REV) == NULL)
2191 	return FAIL;
2192     cctx->ctx_has_cmdmod = FALSE;
2193     return OK;
2194 }
2195 
2196     static int
2197 misplaced_cmdmod(cctx_T *cctx)
2198 {
2199     garray_T	*instr = &cctx->ctx_instr;
2200 
2201     if (cctx->ctx_has_cmdmod
2202 	    && ((isn_T *)instr->ga_data)[instr->ga_len - 1].isn_type
2203 								 == ISN_CMDMOD)
2204     {
2205 	emsg(_(e_misplaced_command_modifier));
2206 	return TRUE;
2207     }
2208     return FALSE;
2209 }
2210 
2211 /*
2212  * Get the index of the current instruction.
2213  * This compenstates for a preceding ISN_CMDMOD and ISN_PROF_START.
2214  */
2215     static int
2216 current_instr_idx(cctx_T *cctx)
2217 {
2218     garray_T	*instr = &cctx->ctx_instr;
2219     int		idx = instr->ga_len;
2220 
2221     if (cctx->ctx_has_cmdmod && ((isn_T *)instr->ga_data)[idx - 1]
2222 						       .isn_type == ISN_CMDMOD)
2223 	--idx;
2224 #ifdef FEAT_PROFILE
2225     if (cctx->ctx_profiling && ((isn_T *)instr->ga_data)[idx - 1]
2226 						   .isn_type == ISN_PROF_START)
2227 	--idx;
2228 #endif
2229     return idx;
2230 }
2231 
2232 #ifdef FEAT_PROFILE
2233     static void
2234 may_generate_prof_end(cctx_T *cctx, int prof_lnum)
2235 {
2236     if (cctx->ctx_profiling && prof_lnum >= 0)
2237 	generate_instr(cctx, ISN_PROF_END);
2238 }
2239 #endif
2240 
2241 /*
2242  * Reserve space for a local variable.
2243  * Return the variable or NULL if it failed.
2244  */
2245     static lvar_T *
2246 reserve_local(
2247 	cctx_T	*cctx,
2248 	char_u	*name,
2249 	size_t	len,
2250 	int	isConst,
2251 	type_T	*type)
2252 {
2253     lvar_T  *lvar;
2254 
2255     if (arg_exists(name, len, NULL, NULL, NULL, cctx) == OK)
2256     {
2257 	emsg_namelen(_(e_str_is_used_as_argument), name, (int)len);
2258 	return NULL;
2259     }
2260 
2261     if (ga_grow(&cctx->ctx_locals, 1) == FAIL)
2262 	return NULL;
2263     lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + cctx->ctx_locals.ga_len++;
2264     CLEAR_POINTER(lvar);
2265 
2266     // Every local variable uses the next entry on the stack.  We could re-use
2267     // the last ones when leaving a scope, but then variables used in a closure
2268     // might get overwritten.  To keep things simple do not re-use stack
2269     // entries.  This is less efficient, but memory is cheap these days.
2270     lvar->lv_idx = cctx->ctx_locals_count++;
2271 
2272     lvar->lv_name = vim_strnsave(name, len == 0 ? STRLEN(name) : len);
2273     lvar->lv_const = isConst;
2274     lvar->lv_type = type;
2275 
2276     return lvar;
2277 }
2278 
2279 /*
2280  * Remove local variables above "new_top".
2281  */
2282     static void
2283 unwind_locals(cctx_T *cctx, int new_top)
2284 {
2285     if (cctx->ctx_locals.ga_len > new_top)
2286     {
2287 	int	idx;
2288 	lvar_T	*lvar;
2289 
2290 	for (idx = new_top; idx < cctx->ctx_locals.ga_len; ++idx)
2291 	{
2292 	    lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + idx;
2293 	    vim_free(lvar->lv_name);
2294 	}
2295     }
2296     cctx->ctx_locals.ga_len = new_top;
2297 }
2298 
2299 /*
2300  * Free all local variables.
2301  */
2302     static void
2303 free_locals(cctx_T *cctx)
2304 {
2305     unwind_locals(cctx, 0);
2306     ga_clear(&cctx->ctx_locals);
2307 }
2308 
2309 /*
2310  * If "check_writable" is ASSIGN_CONST give an error if the variable was
2311  * defined with :final or :const, if "check_writable" is ASSIGN_FINAL give an
2312  * error if the variable was defined with :const.
2313  */
2314     static int
2315 check_item_writable(svar_T *sv, int check_writable, char_u *name)
2316 {
2317     if ((check_writable == ASSIGN_CONST && sv->sv_const != 0)
2318 	    || (check_writable == ASSIGN_FINAL
2319 					      && sv->sv_const == ASSIGN_CONST))
2320     {
2321 	semsg(_(e_readonlyvar), name);
2322 	return FAIL;
2323     }
2324     return OK;
2325 }
2326 
2327 /*
2328  * Find "name" in script-local items of script "sid".
2329  * Pass "check_writable" to check_item_writable().
2330  * Returns the index in "sn_var_vals" if found.
2331  * If found but not in "sn_var_vals" returns -1.
2332  * If not found or the variable is not writable returns -2.
2333  */
2334     int
2335 get_script_item_idx(int sid, char_u *name, int check_writable, cctx_T *cctx)
2336 {
2337     hashtab_T	    *ht;
2338     dictitem_T	    *di;
2339     scriptitem_T    *si = SCRIPT_ITEM(sid);
2340     svar_T	    *sv;
2341     int		    idx;
2342 
2343     if (!SCRIPT_ID_VALID(sid))
2344 	return -1;
2345     if (sid == current_sctx.sc_sid)
2346     {
2347 	sallvar_T *sav = find_script_var(name, 0, cctx);
2348 
2349 	if (sav == NULL)
2350 	    return -2;
2351 	idx = sav->sav_var_vals_idx;
2352 	sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
2353 	if (check_item_writable(sv, check_writable, name) == FAIL)
2354 	    return -2;
2355 	return idx;
2356     }
2357 
2358     // First look the name up in the hashtable.
2359     ht = &SCRIPT_VARS(sid);
2360     di = find_var_in_ht(ht, 0, name, TRUE);
2361     if (di == NULL)
2362 	return -2;
2363 
2364     // Now find the svar_T index in sn_var_vals.
2365     for (idx = 0; idx < si->sn_var_vals.ga_len; ++idx)
2366     {
2367 	sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
2368 	if (sv->sv_tv == &di->di_tv)
2369 	{
2370 	    if (check_item_writable(sv, check_writable, name) == FAIL)
2371 		return -2;
2372 	    return idx;
2373 	}
2374     }
2375     return -1;
2376 }
2377 
2378 /*
2379  * Find "name" in imported items of the current script or in "cctx" if not
2380  * NULL.
2381  */
2382     imported_T *
2383 find_imported(char_u *name, size_t len, cctx_T *cctx)
2384 {
2385     int		    idx;
2386 
2387     if (!SCRIPT_ID_VALID(current_sctx.sc_sid))
2388 	return NULL;
2389     if (cctx != NULL)
2390 	for (idx = 0; idx < cctx->ctx_imports.ga_len; ++idx)
2391 	{
2392 	    imported_T *import = ((imported_T *)cctx->ctx_imports.ga_data)
2393 									 + idx;
2394 
2395 	    if (len == 0 ? STRCMP(name, import->imp_name) == 0
2396 			 : STRLEN(import->imp_name) == len
2397 				  && STRNCMP(name, import->imp_name, len) == 0)
2398 		return import;
2399 	}
2400 
2401     return find_imported_in_script(name, len, current_sctx.sc_sid);
2402 }
2403 
2404     imported_T *
2405 find_imported_in_script(char_u *name, size_t len, int sid)
2406 {
2407     scriptitem_T    *si;
2408     int		    idx;
2409 
2410     if (!SCRIPT_ID_VALID(sid))
2411 	return NULL;
2412     si = SCRIPT_ITEM(sid);
2413     for (idx = 0; idx < si->sn_imports.ga_len; ++idx)
2414     {
2415 	imported_T *import = ((imported_T *)si->sn_imports.ga_data) + idx;
2416 
2417 	if (len == 0 ? STRCMP(name, import->imp_name) == 0
2418 		     : STRLEN(import->imp_name) == len
2419 				  && STRNCMP(name, import->imp_name, len) == 0)
2420 	    return import;
2421     }
2422     return NULL;
2423 }
2424 
2425 /*
2426  * Free all imported variables.
2427  */
2428     static void
2429 free_imported(cctx_T *cctx)
2430 {
2431     int idx;
2432 
2433     for (idx = 0; idx < cctx->ctx_imports.ga_len; ++idx)
2434     {
2435 	imported_T *import = ((imported_T *)cctx->ctx_imports.ga_data) + idx;
2436 
2437 	vim_free(import->imp_name);
2438     }
2439     ga_clear(&cctx->ctx_imports);
2440 }
2441 
2442 /*
2443  * Return a pointer to the next line that isn't empty or only contains a
2444  * comment. Skips over white space.
2445  * Returns NULL if there is none.
2446  */
2447     char_u *
2448 peek_next_line_from_context(cctx_T *cctx)
2449 {
2450     int lnum = cctx->ctx_lnum;
2451 
2452     while (++lnum < cctx->ctx_ufunc->uf_lines.ga_len)
2453     {
2454 	char_u *line = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[lnum];
2455 	char_u *p;
2456 
2457 	// ignore NULLs inserted for continuation lines
2458 	if (line != NULL)
2459 	{
2460 	    p = skipwhite(line);
2461 	    if (vim9_bad_comment(p))
2462 		return NULL;
2463 	    if (*p != NUL && !vim9_comment_start(p))
2464 		return p;
2465 	}
2466     }
2467     return NULL;
2468 }
2469 
2470 /*
2471  * Called when checking for a following operator at "arg".  When the rest of
2472  * the line is empty or only a comment, peek the next line.  If there is a next
2473  * line return a pointer to it and set "nextp".
2474  * Otherwise skip over white space.
2475  */
2476     static char_u *
2477 may_peek_next_line(cctx_T *cctx, char_u *arg, char_u **nextp)
2478 {
2479     char_u *p = skipwhite(arg);
2480 
2481     *nextp = NULL;
2482     if (*p == NUL || (VIM_ISWHITE(*arg) && vim9_comment_start(p)))
2483     {
2484 	*nextp = peek_next_line_from_context(cctx);
2485 	if (*nextp != NULL)
2486 	    return *nextp;
2487     }
2488     return p;
2489 }
2490 
2491 /*
2492  * Get the next line of the function from "cctx".
2493  * Skips over empty lines.  Skips over comment lines if "skip_comment" is TRUE.
2494  * Returns NULL when at the end.
2495  */
2496     char_u *
2497 next_line_from_context(cctx_T *cctx, int skip_comment)
2498 {
2499     char_u	*line;
2500 
2501     do
2502     {
2503 	++cctx->ctx_lnum;
2504 	if (cctx->ctx_lnum >= cctx->ctx_ufunc->uf_lines.ga_len)
2505 	{
2506 	    line = NULL;
2507 	    break;
2508 	}
2509 	line = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum];
2510 	cctx->ctx_line_start = line;
2511 	SOURCING_LNUM = cctx->ctx_lnum + 1;
2512     } while (line == NULL || *skipwhite(line) == NUL
2513 		     || (skip_comment && vim9_comment_start(skipwhite(line))));
2514     return line;
2515 }
2516 
2517 /*
2518  * Skip over white space at "whitep" and assign to "*arg".
2519  * If "*arg" is at the end of the line, advance to the next line.
2520  * Also when "whitep" points to white space and "*arg" is on a "#".
2521  * Return FAIL if beyond the last line, "*arg" is unmodified then.
2522  */
2523     static int
2524 may_get_next_line(char_u *whitep, char_u **arg, cctx_T *cctx)
2525 {
2526     *arg = skipwhite(whitep);
2527     if (vim9_bad_comment(*arg))
2528 	return FAIL;
2529     if (**arg == NUL || (VIM_ISWHITE(*whitep) && vim9_comment_start(*arg)))
2530     {
2531 	char_u *next = next_line_from_context(cctx, TRUE);
2532 
2533 	if (next == NULL)
2534 	    return FAIL;
2535 	*arg = skipwhite(next);
2536     }
2537     return OK;
2538 }
2539 
2540 /*
2541  * Idem, and give an error when failed.
2542  */
2543     static int
2544 may_get_next_line_error(char_u *whitep, char_u **arg, cctx_T *cctx)
2545 {
2546     if (may_get_next_line(whitep, arg, cctx) == FAIL)
2547     {
2548 	SOURCING_LNUM = cctx->ctx_lnum + 1;
2549 	emsg(_(e_line_incomplete));
2550 	return FAIL;
2551     }
2552     return OK;
2553 }
2554 
2555 
2556 // Structure passed between the compile_expr* functions to keep track of
2557 // constants that have been parsed but for which no code was produced yet.  If
2558 // possible expressions on these constants are applied at compile time.  If
2559 // that is not possible, the code to push the constants needs to be generated
2560 // before other instructions.
2561 // Using 50 should be more than enough of 5 levels of ().
2562 #define PPSIZE 50
2563 typedef struct {
2564     typval_T	pp_tv[PPSIZE];	// stack of ppconst constants
2565     int		pp_used;	// active entries in pp_tv[]
2566     int		pp_is_const;	// all generated code was constants, used for a
2567 				// list or dict with constant members
2568 } ppconst_T;
2569 
2570 static int compile_expr0_ext(char_u **arg,  cctx_T *cctx, int *is_const);
2571 static int compile_expr0(char_u **arg,  cctx_T *cctx);
2572 static int compile_expr1(char_u **arg,  cctx_T *cctx, ppconst_T *ppconst);
2573 
2574 /*
2575  * Generate a PUSH instruction for "tv".
2576  * "tv" will be consumed or cleared.
2577  * Nothing happens if "tv" is NULL or of type VAR_UNKNOWN;
2578  */
2579     static int
2580 generate_tv_PUSH(cctx_T *cctx, typval_T *tv)
2581 {
2582     if (tv != NULL)
2583     {
2584 	switch (tv->v_type)
2585 	{
2586 	    case VAR_UNKNOWN:
2587 		break;
2588 	    case VAR_BOOL:
2589 		generate_PUSHBOOL(cctx, tv->vval.v_number);
2590 		break;
2591 	    case VAR_SPECIAL:
2592 		generate_PUSHSPEC(cctx, tv->vval.v_number);
2593 		break;
2594 	    case VAR_NUMBER:
2595 		generate_PUSHNR(cctx, tv->vval.v_number);
2596 		break;
2597 #ifdef FEAT_FLOAT
2598 	    case VAR_FLOAT:
2599 		generate_PUSHF(cctx, tv->vval.v_float);
2600 		break;
2601 #endif
2602 	    case VAR_BLOB:
2603 		generate_PUSHBLOB(cctx, tv->vval.v_blob);
2604 		tv->vval.v_blob = NULL;
2605 		break;
2606 	    case VAR_STRING:
2607 		generate_PUSHS(cctx, tv->vval.v_string);
2608 		tv->vval.v_string = NULL;
2609 		break;
2610 	    default:
2611 		iemsg("constant type not supported");
2612 		clear_tv(tv);
2613 		return FAIL;
2614 	}
2615 	tv->v_type = VAR_UNKNOWN;
2616     }
2617     return OK;
2618 }
2619 
2620 /*
2621  * Generate code for any ppconst entries.
2622  */
2623     static int
2624 generate_ppconst(cctx_T *cctx, ppconst_T *ppconst)
2625 {
2626     int	    i;
2627     int	    ret = OK;
2628     int	    save_skip = cctx->ctx_skip;
2629 
2630     cctx->ctx_skip = SKIP_NOT;
2631     for (i = 0; i < ppconst->pp_used; ++i)
2632 	if (generate_tv_PUSH(cctx, &ppconst->pp_tv[i]) == FAIL)
2633 	    ret = FAIL;
2634     ppconst->pp_used = 0;
2635     cctx->ctx_skip = save_skip;
2636     return ret;
2637 }
2638 
2639 /*
2640  * Clear ppconst constants.  Used when failing.
2641  */
2642     static void
2643 clear_ppconst(ppconst_T *ppconst)
2644 {
2645     int	    i;
2646 
2647     for (i = 0; i < ppconst->pp_used; ++i)
2648 	clear_tv(&ppconst->pp_tv[i]);
2649     ppconst->pp_used = 0;
2650 }
2651 
2652 /*
2653  * Generate an instruction to load script-local variable "name", without the
2654  * leading "s:".
2655  * Also finds imported variables.
2656  */
2657     static int
2658 compile_load_scriptvar(
2659 	cctx_T *cctx,
2660 	char_u *name,	    // variable NUL terminated
2661 	char_u *start,	    // start of variable
2662 	char_u **end,	    // end of variable
2663 	int    error)	    // when TRUE may give error
2664 {
2665     scriptitem_T    *si;
2666     int		    idx;
2667     imported_T	    *import;
2668 
2669     if (!SCRIPT_ID_VALID(current_sctx.sc_sid))
2670 	return FAIL;
2671     si = SCRIPT_ITEM(current_sctx.sc_sid);
2672     idx = get_script_item_idx(current_sctx.sc_sid, name, 0, cctx);
2673     if (idx == -1 || si->sn_version != SCRIPT_VERSION_VIM9)
2674     {
2675 	// variable is not in sn_var_vals: old style script.
2676 	return generate_OLDSCRIPT(cctx, ISN_LOADS, name, current_sctx.sc_sid,
2677 								       &t_any);
2678     }
2679     if (idx >= 0)
2680     {
2681 	svar_T		*sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
2682 
2683 	generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
2684 					current_sctx.sc_sid, idx, sv->sv_type);
2685 	return OK;
2686     }
2687 
2688     import = find_imported(name, 0, cctx);
2689     if (import != NULL)
2690     {
2691 	if (import->imp_flags & IMP_FLAGS_STAR)
2692 	{
2693 	    char_u	*p = skipwhite(*end);
2694 	    char_u	*exp_name;
2695 	    int		cc;
2696 	    ufunc_T	*ufunc;
2697 	    type_T	*type;
2698 
2699 	    // Used "import * as Name", need to lookup the member.
2700 	    if (*p != '.')
2701 	    {
2702 		semsg(_(e_expected_dot_after_name_str), start);
2703 		return FAIL;
2704 	    }
2705 	    ++p;
2706 	    if (VIM_ISWHITE(*p))
2707 	    {
2708 		emsg(_(e_no_white_space_allowed_after_dot));
2709 		return FAIL;
2710 	    }
2711 
2712 	    // isolate one name
2713 	    exp_name = p;
2714 	    while (eval_isnamec(*p))
2715 		++p;
2716 	    cc = *p;
2717 	    *p = NUL;
2718 
2719 	    idx = find_exported(import->imp_sid, exp_name, &ufunc, &type,
2720 								   cctx, TRUE);
2721 	    *p = cc;
2722 	    p = skipwhite(p);
2723 
2724 	    // TODO: what if it is a function?
2725 	    if (idx < 0)
2726 		return FAIL;
2727 	    *end = p;
2728 
2729 	    generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
2730 		    import->imp_sid,
2731 		    idx,
2732 		    type);
2733 	}
2734 	else if (import->imp_funcname != NULL)
2735 	    generate_PUSHFUNC(cctx, import->imp_funcname, import->imp_type);
2736 	else
2737 	    generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
2738 		    import->imp_sid,
2739 		    import->imp_var_vals_idx,
2740 		    import->imp_type);
2741 	return OK;
2742     }
2743 
2744     if (error)
2745 	semsg(_(e_item_not_found_str), name);
2746     return FAIL;
2747 }
2748 
2749     static int
2750 generate_funcref(cctx_T *cctx, char_u *name)
2751 {
2752     ufunc_T *ufunc = find_func(name, FALSE, cctx);
2753 
2754     if (ufunc == NULL)
2755 	return FAIL;
2756 
2757     // Need to compile any default values to get the argument types.
2758     if (func_needs_compiling(ufunc, PROFILING(ufunc))
2759 	    && compile_def_function(ufunc, TRUE, PROFILING(ufunc), NULL)
2760 								       == FAIL)
2761 	return FAIL;
2762     return generate_PUSHFUNC(cctx, ufunc->uf_name, ufunc->uf_func_type);
2763 }
2764 
2765 /*
2766  * Compile a variable name into a load instruction.
2767  * "end" points to just after the name.
2768  * "is_expr" is TRUE when evaluating an expression, might be a funcref.
2769  * When "error" is FALSE do not give an error when not found.
2770  */
2771     static int
2772 compile_load(
2773 	char_u **arg,
2774 	char_u *end_arg,
2775 	cctx_T	*cctx,
2776 	int	is_expr,
2777 	int	error)
2778 {
2779     type_T	*type;
2780     char_u	*name = NULL;
2781     char_u	*end = end_arg;
2782     int		res = FAIL;
2783     int		prev_called_emsg = called_emsg;
2784 
2785     if (*(*arg + 1) == ':')
2786     {
2787 	// load namespaced variable
2788 	if (end <= *arg + 2)
2789 	{
2790 	    isntype_T  isn_type;
2791 
2792 	    switch (**arg)
2793 	    {
2794 		case 'g': isn_type = ISN_LOADGDICT; break;
2795 		case 'w': isn_type = ISN_LOADWDICT; break;
2796 		case 't': isn_type = ISN_LOADTDICT; break;
2797 		case 'b': isn_type = ISN_LOADBDICT; break;
2798 		default:
2799 		    semsg(_(e_namespace_not_supported_str), *arg);
2800 		    goto theend;
2801 	    }
2802 	    if (generate_instr_type(cctx, isn_type, &t_dict_any) == NULL)
2803 		goto theend;
2804 	    res = OK;
2805 	}
2806 	else
2807 	{
2808 	    isntype_T  isn_type = ISN_DROP;
2809 
2810 	    name = vim_strnsave(*arg + 2, end - (*arg + 2));
2811 	    if (name == NULL)
2812 		return FAIL;
2813 
2814 	    switch (**arg)
2815 	    {
2816 		case 'v': res = generate_LOADV(cctx, name, error);
2817 			  break;
2818 		case 's': res = compile_load_scriptvar(cctx, name,
2819 							    NULL, NULL, error);
2820 			  break;
2821 		case 'g': if (vim_strchr(name, AUTOLOAD_CHAR) == NULL)
2822 			      isn_type = ISN_LOADG;
2823 			  else
2824 			  {
2825 			      isn_type = ISN_LOADAUTO;
2826 			      vim_free(name);
2827 			      name = vim_strnsave(*arg, end - *arg);
2828 			      if (name == NULL)
2829 				  return FAIL;
2830 			  }
2831 			  break;
2832 		case 'w': isn_type = ISN_LOADW; break;
2833 		case 't': isn_type = ISN_LOADT; break;
2834 		case 'b': isn_type = ISN_LOADB; break;
2835 		default:  // cannot happen, just in case
2836 			  semsg(_(e_namespace_not_supported_str), *arg);
2837 			  goto theend;
2838 	    }
2839 	    if (isn_type != ISN_DROP)
2840 	    {
2841 		// Global, Buffer-local, Window-local and Tabpage-local
2842 		// variables can be defined later, thus we don't check if it
2843 		// exists, give error at runtime.
2844 		res = generate_LOAD(cctx, isn_type, 0, name, &t_any);
2845 	    }
2846 	}
2847     }
2848     else
2849     {
2850 	size_t	    len = end - *arg;
2851 	int	    idx;
2852 	int	    gen_load = FALSE;
2853 	int	    gen_load_outer = 0;
2854 
2855 	name = vim_strnsave(*arg, end - *arg);
2856 	if (name == NULL)
2857 	    return FAIL;
2858 
2859 	if (arg_exists(*arg, len, &idx, &type, &gen_load_outer, cctx) == OK)
2860 	{
2861 	    if (gen_load_outer == 0)
2862 		gen_load = TRUE;
2863 	}
2864 	else
2865 	{
2866 	    lvar_T lvar;
2867 
2868 	    if (lookup_local(*arg, len, &lvar, cctx) == OK)
2869 	    {
2870 		type = lvar.lv_type;
2871 		idx = lvar.lv_idx;
2872 		if (lvar.lv_from_outer != 0)
2873 		    gen_load_outer = lvar.lv_from_outer;
2874 		else
2875 		    gen_load = TRUE;
2876 	    }
2877 	    else
2878 	    {
2879 		// "var" can be script-local even without using "s:" if it
2880 		// already exists in a Vim9 script or when it's imported.
2881 		if (script_var_exists(*arg, len, TRUE, cctx) == OK
2882 			|| find_imported(name, 0, cctx) != NULL)
2883 		   res = compile_load_scriptvar(cctx, name, *arg, &end, FALSE);
2884 
2885 		// When evaluating an expression and the name starts with an
2886 		// uppercase letter or "x:" it can be a user defined function.
2887 		// TODO: this is just guessing
2888 		if (res == FAIL && is_expr
2889 				   && (ASCII_ISUPPER(*name) || name[1] == ':'))
2890 		    res = generate_funcref(cctx, name);
2891 	    }
2892 	}
2893 	if (gen_load)
2894 	    res = generate_LOAD(cctx, ISN_LOAD, idx, NULL, type);
2895 	if (gen_load_outer > 0)
2896 	{
2897 	    res = generate_LOADOUTER(cctx, idx, gen_load_outer, type);
2898 	    cctx->ctx_outer_used = TRUE;
2899 	}
2900     }
2901 
2902     *arg = end;
2903 
2904 theend:
2905     if (res == FAIL && error && called_emsg == prev_called_emsg)
2906 	semsg(_(e_variable_not_found_str), name);
2907     vim_free(name);
2908     return res;
2909 }
2910 
2911 /*
2912  * Compile the argument expressions.
2913  * "arg" points to just after the "(" and is advanced to after the ")"
2914  */
2915     static int
2916 compile_arguments(char_u **arg, cctx_T *cctx, int *argcount)
2917 {
2918     char_u  *p = *arg;
2919     char_u  *whitep = *arg;
2920     int	    must_end = FALSE;
2921 
2922     for (;;)
2923     {
2924 	if (may_get_next_line(whitep, &p, cctx) == FAIL)
2925 	    goto failret;
2926 	if (*p == ')')
2927 	{
2928 	    *arg = p + 1;
2929 	    return OK;
2930 	}
2931 	if (must_end)
2932 	{
2933 	    semsg(_(e_missing_comma_before_argument_str), p);
2934 	    return FAIL;
2935 	}
2936 
2937 	if (compile_expr0(&p, cctx) == FAIL)
2938 	    return FAIL;
2939 	++*argcount;
2940 
2941 	if (*p != ',' && *skipwhite(p) == ',')
2942 	{
2943 	    semsg(_(e_no_white_space_allowed_before_str_str), ",", p);
2944 	    p = skipwhite(p);
2945 	}
2946 	if (*p == ',')
2947 	{
2948 	    ++p;
2949 	    if (*p != NUL && !VIM_ISWHITE(*p))
2950 		semsg(_(e_white_space_required_after_str_str), ",", p - 1);
2951 	}
2952 	else
2953 	    must_end = TRUE;
2954 	whitep = p;
2955 	p = skipwhite(p);
2956     }
2957 failret:
2958     emsg(_(e_missing_close));
2959     return FAIL;
2960 }
2961 
2962 /*
2963  * Compile a function call:  name(arg1, arg2)
2964  * "arg" points to "name", "arg + varlen" to the "(".
2965  * "argcount_init" is 1 for "value->method()"
2966  * Instructions:
2967  *	EVAL arg1
2968  *	EVAL arg2
2969  *	BCALL / DCALL / UCALL
2970  */
2971     static int
2972 compile_call(
2973 	char_u	    **arg,
2974 	size_t	    varlen,
2975 	cctx_T	    *cctx,
2976 	ppconst_T   *ppconst,
2977 	int	    argcount_init)
2978 {
2979     char_u	*name = *arg;
2980     char_u	*p;
2981     int		argcount = argcount_init;
2982     char_u	namebuf[100];
2983     char_u	fname_buf[FLEN_FIXED + 1];
2984     char_u	*tofree = NULL;
2985     int		error = FCERR_NONE;
2986     ufunc_T	*ufunc = NULL;
2987     int		res = FAIL;
2988     int		is_autoload;
2989 
2990     // we can evaluate "has('name')" at compile time
2991     if (varlen == 3 && STRNCMP(*arg, "has", 3) == 0)
2992     {
2993 	char_u	    *s = skipwhite(*arg + varlen + 1);
2994 	typval_T    argvars[2];
2995 
2996 	argvars[0].v_type = VAR_UNKNOWN;
2997 	if (*s == '"')
2998 	    (void)eval_string(&s, &argvars[0], TRUE);
2999 	else if (*s == '\'')
3000 	    (void)eval_lit_string(&s, &argvars[0], TRUE);
3001 	s = skipwhite(s);
3002 	if (*s == ')' && argvars[0].v_type == VAR_STRING
3003 		&& !dynamic_feature(argvars[0].vval.v_string))
3004 	{
3005 	    typval_T	*tv = &ppconst->pp_tv[ppconst->pp_used];
3006 
3007 	    *arg = s + 1;
3008 	    argvars[1].v_type = VAR_UNKNOWN;
3009 	    tv->v_type = VAR_NUMBER;
3010 	    tv->vval.v_number = 0;
3011 	    f_has(argvars, tv);
3012 	    clear_tv(&argvars[0]);
3013 	    ++ppconst->pp_used;
3014 	    return OK;
3015 	}
3016 	clear_tv(&argvars[0]);
3017     }
3018 
3019     if (generate_ppconst(cctx, ppconst) == FAIL)
3020 	return FAIL;
3021 
3022     if (varlen >= sizeof(namebuf))
3023     {
3024 	semsg(_(e_name_too_long_str), name);
3025 	return FAIL;
3026     }
3027     vim_strncpy(namebuf, *arg, varlen);
3028     name = fname_trans_sid(namebuf, fname_buf, &tofree, &error);
3029 
3030     *arg = skipwhite(*arg + varlen + 1);
3031     if (compile_arguments(arg, cctx, &argcount) == FAIL)
3032 	goto theend;
3033 
3034     is_autoload = vim_strchr(name, AUTOLOAD_CHAR) != NULL;
3035     if (ASCII_ISLOWER(*name) && name[1] != ':' && !is_autoload)
3036     {
3037 	int	    idx;
3038 
3039 	// builtin function
3040 	idx = find_internal_func(name);
3041 	if (idx >= 0)
3042 	{
3043 	    if (STRCMP(name, "flatten") == 0)
3044 	    {
3045 		emsg(_(e_cannot_use_flatten_in_vim9_script));
3046 		goto theend;
3047 	    }
3048 
3049 	    if (STRCMP(name, "add") == 0 && argcount == 2)
3050 	    {
3051 		garray_T    *stack = &cctx->ctx_type_stack;
3052 		type_T	    *type = ((type_T **)stack->ga_data)[
3053 							    stack->ga_len - 2];
3054 
3055 		// add() can be compiled to instructions if we know the type
3056 		if (type->tt_type == VAR_LIST)
3057 		{
3058 		    // inline "add(list, item)" so that the type can be checked
3059 		    res = generate_LISTAPPEND(cctx);
3060 		    idx = -1;
3061 		}
3062 		else if (type->tt_type == VAR_BLOB)
3063 		{
3064 		    // inline "add(blob, nr)" so that the type can be checked
3065 		    res = generate_BLOBAPPEND(cctx);
3066 		    idx = -1;
3067 		}
3068 	    }
3069 
3070 	    if (idx >= 0)
3071 		res = generate_BCALL(cctx, idx, argcount, argcount_init == 1);
3072 	}
3073 	else
3074 	    semsg(_(e_unknownfunc), namebuf);
3075 	goto theend;
3076     }
3077 
3078     // An argument or local variable can be a function reference, this
3079     // overrules a function name.
3080     if (lookup_local(namebuf, varlen, NULL, cctx) == FAIL
3081 	    && arg_exists(namebuf, varlen, NULL, NULL, NULL, cctx) != OK)
3082     {
3083 	// If we can find the function by name generate the right call.
3084 	// Skip global functions here, a local funcref takes precedence.
3085 	ufunc = find_func(name, FALSE, cctx);
3086 	if (ufunc != NULL && !func_is_global(ufunc))
3087 	{
3088 	    res = generate_CALL(cctx, ufunc, argcount);
3089 	    goto theend;
3090 	}
3091     }
3092 
3093     // If the name is a variable, load it and use PCALL.
3094     // Not for g:Func(), we don't know if it is a variable or not.
3095     // Not for eome#Func(), it will be loaded later.
3096     p = namebuf;
3097     if (STRNCMP(namebuf, "g:", 2) != 0 && !is_autoload
3098 	    && compile_load(&p, namebuf + varlen, cctx, FALSE, FALSE) == OK)
3099     {
3100 	garray_T    *stack = &cctx->ctx_type_stack;
3101 	type_T	    *type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
3102 
3103 	res = generate_PCALL(cctx, argcount, namebuf, type, FALSE);
3104 	goto theend;
3105     }
3106 
3107     // If we can find a global function by name generate the right call.
3108     if (ufunc != NULL)
3109     {
3110 	res = generate_CALL(cctx, ufunc, argcount);
3111 	goto theend;
3112     }
3113 
3114     // A global function may be defined only later.  Need to figure out at
3115     // runtime.  Also handles a FuncRef at runtime.
3116     if (STRNCMP(namebuf, "g:", 2) == 0 || is_autoload)
3117 	res = generate_UCALL(cctx, name, argcount);
3118     else
3119 	semsg(_(e_unknownfunc), namebuf);
3120 
3121 theend:
3122     vim_free(tofree);
3123     return res;
3124 }
3125 
3126 // like NAMESPACE_CHAR but with 'a' and 'l'.
3127 #define VIM9_NAMESPACE_CHAR	(char_u *)"bgstvw"
3128 
3129 /*
3130  * Find the end of a variable or function name.  Unlike find_name_end() this
3131  * does not recognize magic braces.
3132  * When "use_namespace" is TRUE recognize "b:", "s:", etc.
3133  * Return a pointer to just after the name.  Equal to "arg" if there is no
3134  * valid name.
3135  */
3136     char_u *
3137 to_name_end(char_u *arg, int use_namespace)
3138 {
3139     char_u	*p;
3140 
3141     // Quick check for valid starting character.
3142     if (!eval_isnamec1(*arg))
3143 	return arg;
3144 
3145     for (p = arg + 1; *p != NUL && eval_isnamec(*p); MB_PTR_ADV(p))
3146 	// Include a namespace such as "s:var" and "v:var".  But "n:" is not
3147 	// and can be used in slice "[n:]".
3148 	if (*p == ':' && (p != arg + 1
3149 			     || !use_namespace
3150 			     || vim_strchr(VIM9_NAMESPACE_CHAR, *arg) == NULL))
3151 	    break;
3152     return p;
3153 }
3154 
3155 /*
3156  * Like to_name_end() but also skip over a list or dict constant.
3157  * This intentionally does not handle line continuation.
3158  */
3159     char_u *
3160 to_name_const_end(char_u *arg)
3161 {
3162     char_u	*p = to_name_end(arg, TRUE);
3163     typval_T	rettv;
3164 
3165     if (p == arg && *arg == '[')
3166     {
3167 
3168 	// Can be "[1, 2, 3]->Func()".
3169 	if (eval_list(&p, &rettv, NULL, FALSE) == FAIL)
3170 	    p = arg;
3171     }
3172     return p;
3173 }
3174 
3175 /*
3176  * parse a list: [expr, expr]
3177  * "*arg" points to the '['.
3178  * ppconst->pp_is_const is set if all items are a constant.
3179  */
3180     static int
3181 compile_list(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3182 {
3183     char_u	*p = skipwhite(*arg + 1);
3184     char_u	*whitep = *arg + 1;
3185     int		count = 0;
3186     int		is_const;
3187     int		is_all_const = TRUE;	// reset when non-const encountered
3188 
3189     for (;;)
3190     {
3191 	if (may_get_next_line(whitep, &p, cctx) == FAIL)
3192 	{
3193 	    semsg(_(e_list_end), *arg);
3194 	    return FAIL;
3195 	}
3196 	if (*p == ',')
3197 	{
3198 	    semsg(_(e_no_white_space_allowed_before_str_str), ",", p);
3199 	    return FAIL;
3200 	}
3201 	if (*p == ']')
3202 	{
3203 	    ++p;
3204 	    break;
3205 	}
3206 	if (compile_expr0_ext(&p, cctx, &is_const) == FAIL)
3207 	    return FAIL;
3208 	if (!is_const)
3209 	    is_all_const = FALSE;
3210 	++count;
3211 	if (*p == ',')
3212 	{
3213 	    ++p;
3214 	    if (*p != ']' && !IS_WHITE_OR_NUL(*p))
3215 	    {
3216 		semsg(_(e_white_space_required_after_str_str), ",", p - 1);
3217 		return FAIL;
3218 	    }
3219 	}
3220 	whitep = p;
3221 	p = skipwhite(p);
3222     }
3223     *arg = p;
3224 
3225     ppconst->pp_is_const = is_all_const;
3226     return generate_NEWLIST(cctx, count);
3227 }
3228 
3229 /*
3230  * Parse a lambda: "(arg, arg) => expr"
3231  * "*arg" points to the '('.
3232  * Returns OK/FAIL when a lambda is recognized, NOTDONE if it's not a lambda.
3233  */
3234     static int
3235 compile_lambda(char_u **arg, cctx_T *cctx)
3236 {
3237     int		r;
3238     typval_T	rettv;
3239     ufunc_T	*ufunc;
3240     evalarg_T	evalarg;
3241 
3242     CLEAR_FIELD(evalarg);
3243     evalarg.eval_flags = EVAL_EVALUATE;
3244     evalarg.eval_cctx = cctx;
3245 
3246     // Get the funcref in "rettv".
3247     r = get_lambda_tv(arg, &rettv, TRUE, &evalarg);
3248     if (r != OK)
3249     {
3250 	clear_evalarg(&evalarg, NULL);
3251 	return r;
3252     }
3253 
3254     // "rettv" will now be a partial referencing the function.
3255     ufunc = rettv.vval.v_partial->pt_func;
3256     ++ufunc->uf_refcount;
3257     clear_tv(&rettv);
3258 
3259     // Compile the function into instructions.
3260     compile_def_function(ufunc, TRUE, PROFILING(ufunc), cctx);
3261 
3262     // evalarg.eval_tofree_cmdline may have a copy of the last line and "*arg"
3263     // points into it.  Point to the original line to avoid a dangling pointer.
3264     if (evalarg.eval_tofree_cmdline != NULL)
3265     {
3266 	size_t	off = *arg - evalarg.eval_tofree_cmdline;
3267 
3268 	*arg = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum]
3269 									 + off;
3270     }
3271 
3272     clear_evalarg(&evalarg, NULL);
3273 
3274     if (ufunc->uf_def_status == UF_COMPILED)
3275     {
3276 	// The return type will now be known.
3277 	set_function_type(ufunc);
3278 
3279 	// The function reference count will be 1.  When the ISN_FUNCREF
3280 	// instruction is deleted the reference count is decremented and the
3281 	// function is freed.
3282 	return generate_FUNCREF(cctx, ufunc);
3283     }
3284 
3285     func_ptr_unref(ufunc);
3286     return FAIL;
3287 }
3288 
3289 /*
3290  * parse a dict: {key: val, [key]: val}
3291  * "*arg" points to the '{'.
3292  * ppconst->pp_is_const is set if all item values are a constant.
3293  */
3294     static int
3295 compile_dict(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3296 {
3297     garray_T	*instr = &cctx->ctx_instr;
3298     int		count = 0;
3299     dict_T	*d = dict_alloc();
3300     dictitem_T	*item;
3301     char_u	*whitep = *arg + 1;
3302     char_u	*p;
3303     int		is_const;
3304     int		is_all_const = TRUE;	// reset when non-const encountered
3305 
3306     if (d == NULL)
3307 	return FAIL;
3308     if (generate_ppconst(cctx, ppconst) == FAIL)
3309 	return FAIL;
3310     for (;;)
3311     {
3312 	char_u	    *key = NULL;
3313 
3314 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
3315 	{
3316 	    *arg = NULL;
3317 	    goto failret;
3318 	}
3319 
3320 	if (**arg == '}')
3321 	    break;
3322 
3323 	if (**arg == '[')
3324 	{
3325 	    isn_T	*isn;
3326 
3327 	    // {[expr]: value} uses an evaluated key.
3328 	    *arg = skipwhite(*arg + 1);
3329 	    if (compile_expr0(arg, cctx) == FAIL)
3330 		return FAIL;
3331 	    isn = ((isn_T *)instr->ga_data) + instr->ga_len - 1;
3332 	    if (isn->isn_type == ISN_PUSHNR)
3333 	    {
3334 		char buf[NUMBUFLEN];
3335 
3336 		// Convert to string at compile time.
3337 		vim_snprintf(buf, NUMBUFLEN, "%lld", isn->isn_arg.number);
3338 		isn->isn_type = ISN_PUSHS;
3339 		isn->isn_arg.string = vim_strsave((char_u *)buf);
3340 	    }
3341 	    if (isn->isn_type == ISN_PUSHS)
3342 		key = isn->isn_arg.string;
3343 	    else if (may_generate_2STRING(-1, cctx) == FAIL)
3344 		return FAIL;
3345 	    *arg = skipwhite(*arg);
3346 	    if (**arg != ']')
3347 	    {
3348 		emsg(_(e_missing_matching_bracket_after_dict_key));
3349 		return FAIL;
3350 	    }
3351 	    ++*arg;
3352 	}
3353 	else
3354 	{
3355 	    // {"name": value},
3356 	    // {'name': value},
3357 	    // {name: value} use "name" as a literal key
3358 	    key = get_literal_key(arg);
3359 	    if (key == NULL)
3360 		return FAIL;
3361 	    if (generate_PUSHS(cctx, key) == FAIL)
3362 		return FAIL;
3363 	}
3364 
3365 	// Check for duplicate keys, if using string keys.
3366 	if (key != NULL)
3367 	{
3368 	    item = dict_find(d, key, -1);
3369 	    if (item != NULL)
3370 	    {
3371 		semsg(_(e_duplicate_key), key);
3372 		goto failret;
3373 	    }
3374 	    item = dictitem_alloc(key);
3375 	    if (item != NULL)
3376 	    {
3377 		item->di_tv.v_type = VAR_UNKNOWN;
3378 		item->di_tv.v_lock = 0;
3379 		if (dict_add(d, item) == FAIL)
3380 		    dictitem_free(item);
3381 	    }
3382 	}
3383 
3384 	if (**arg != ':')
3385 	{
3386 	    if (*skipwhite(*arg) == ':')
3387 		semsg(_(e_no_white_space_allowed_before_str_str), ":", *arg);
3388 	    else
3389 		semsg(_(e_missing_dict_colon), *arg);
3390 	    return FAIL;
3391 	}
3392 	whitep = *arg + 1;
3393 	if (!IS_WHITE_OR_NUL(*whitep))
3394 	{
3395 	    semsg(_(e_white_space_required_after_str_str), ":", *arg);
3396 	    return FAIL;
3397 	}
3398 
3399 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
3400 	{
3401 	    *arg = NULL;
3402 	    goto failret;
3403 	}
3404 
3405 	if (compile_expr0_ext(arg, cctx, &is_const) == FAIL)
3406 	    return FAIL;
3407 	if (!is_const)
3408 	    is_all_const = FALSE;
3409 	++count;
3410 
3411 	whitep = *arg;
3412 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
3413 	{
3414 	    *arg = NULL;
3415 	    goto failret;
3416 	}
3417 	if (**arg == '}')
3418 	    break;
3419 	if (**arg != ',')
3420 	{
3421 	    semsg(_(e_missing_dict_comma), *arg);
3422 	    goto failret;
3423 	}
3424 	if (IS_WHITE_OR_NUL(*whitep))
3425 	{
3426 	    semsg(_(e_no_white_space_allowed_before_str_str), ",", whitep);
3427 	    return FAIL;
3428 	}
3429 	whitep = *arg + 1;
3430 	if (!IS_WHITE_OR_NUL(*whitep))
3431 	{
3432 	    semsg(_(e_white_space_required_after_str_str), ",", *arg);
3433 	    return FAIL;
3434 	}
3435 	*arg = skipwhite(whitep);
3436     }
3437 
3438     *arg = *arg + 1;
3439 
3440     // Allow for following comment, after at least one space.
3441     p = skipwhite(*arg);
3442     if (VIM_ISWHITE(**arg) && vim9_comment_start(p))
3443 	*arg += STRLEN(*arg);
3444 
3445     dict_unref(d);
3446     ppconst->pp_is_const = is_all_const;
3447     return generate_NEWDICT(cctx, count);
3448 
3449 failret:
3450     if (*arg == NULL)
3451     {
3452 	semsg(_(e_missing_dict_end), _("[end of lines]"));
3453 	*arg = (char_u *)"";
3454     }
3455     dict_unref(d);
3456     return FAIL;
3457 }
3458 
3459 /*
3460  * Compile "&option".
3461  */
3462     static int
3463 compile_get_option(char_u **arg, cctx_T *cctx)
3464 {
3465     typval_T	rettv;
3466     char_u	*start = *arg;
3467     int		ret;
3468 
3469     // parse the option and get the current value to get the type.
3470     rettv.v_type = VAR_UNKNOWN;
3471     ret = eval_option(arg, &rettv, TRUE);
3472     if (ret == OK)
3473     {
3474 	// include the '&' in the name, eval_option() expects it.
3475 	char_u	*name = vim_strnsave(start, *arg - start);
3476 	type_T	*type = rettv.v_type == VAR_BOOL ? &t_bool
3477 			  : rettv.v_type == VAR_NUMBER ? &t_number : &t_string;
3478 
3479 	ret = generate_LOAD(cctx, ISN_LOADOPT, 0, name, type);
3480 	vim_free(name);
3481     }
3482     clear_tv(&rettv);
3483 
3484     return ret;
3485 }
3486 
3487 /*
3488  * Compile "$VAR".
3489  */
3490     static int
3491 compile_get_env(char_u **arg, cctx_T *cctx)
3492 {
3493     char_u	*start = *arg;
3494     int		len;
3495     int		ret;
3496     char_u	*name;
3497 
3498     ++*arg;
3499     len = get_env_len(arg);
3500     if (len == 0)
3501     {
3502 	semsg(_(e_syntax_error_at_str), start - 1);
3503 	return FAIL;
3504     }
3505 
3506     // include the '$' in the name, eval_env_var() expects it.
3507     name = vim_strnsave(start, len + 1);
3508     ret = generate_LOAD(cctx, ISN_LOADENV, 0, name, &t_string);
3509     vim_free(name);
3510     return ret;
3511 }
3512 
3513 /*
3514  * Compile "@r".
3515  */
3516     static int
3517 compile_get_register(char_u **arg, cctx_T *cctx)
3518 {
3519     int		ret;
3520 
3521     ++*arg;
3522     if (**arg == NUL)
3523     {
3524 	semsg(_(e_syntax_error_at_str), *arg - 1);
3525 	return FAIL;
3526     }
3527     if (!valid_yank_reg(**arg, FALSE))
3528     {
3529 	emsg_invreg(**arg);
3530 	return FAIL;
3531     }
3532     ret = generate_LOAD(cctx, ISN_LOADREG, **arg, NULL, &t_string);
3533     ++*arg;
3534     return ret;
3535 }
3536 
3537 /*
3538  * Apply leading '!', '-' and '+' to constant "rettv".
3539  * When "numeric_only" is TRUE do not apply '!'.
3540  */
3541     static int
3542 apply_leader(typval_T *rettv, int numeric_only, char_u *start, char_u **end)
3543 {
3544     char_u *p = *end;
3545 
3546     // this works from end to start
3547     while (p > start)
3548     {
3549 	--p;
3550 	if (*p == '-' || *p == '+')
3551 	{
3552 	    // only '-' has an effect, for '+' we only check the type
3553 #ifdef FEAT_FLOAT
3554 	    if (rettv->v_type == VAR_FLOAT)
3555 	    {
3556 		if (*p == '-')
3557 		    rettv->vval.v_float = -rettv->vval.v_float;
3558 	    }
3559 	    else
3560 #endif
3561 	    {
3562 		varnumber_T	val;
3563 		int		error = FALSE;
3564 
3565 		// tv_get_number_chk() accepts a string, but we don't want that
3566 		// here
3567 		if (check_not_string(rettv) == FAIL)
3568 		    return FAIL;
3569 		val = tv_get_number_chk(rettv, &error);
3570 		clear_tv(rettv);
3571 		if (error)
3572 		    return FAIL;
3573 		if (*p == '-')
3574 		    val = -val;
3575 		rettv->v_type = VAR_NUMBER;
3576 		rettv->vval.v_number = val;
3577 	    }
3578 	}
3579 	else if (numeric_only)
3580 	{
3581 	    ++p;
3582 	    break;
3583 	}
3584 	else if (*p == '!')
3585 	{
3586 	    int v = tv2bool(rettv);
3587 
3588 	    // '!' is permissive in the type.
3589 	    clear_tv(rettv);
3590 	    rettv->v_type = VAR_BOOL;
3591 	    rettv->vval.v_number = v ? VVAL_FALSE : VVAL_TRUE;
3592 	}
3593     }
3594     *end = p;
3595     return OK;
3596 }
3597 
3598 /*
3599  * Recognize v: variables that are constants and set "rettv".
3600  */
3601     static void
3602 get_vim_constant(char_u **arg, typval_T *rettv)
3603 {
3604     if (STRNCMP(*arg, "v:true", 6) == 0)
3605     {
3606 	rettv->v_type = VAR_BOOL;
3607 	rettv->vval.v_number = VVAL_TRUE;
3608 	*arg += 6;
3609     }
3610     else if (STRNCMP(*arg, "v:false", 7) == 0)
3611     {
3612 	rettv->v_type = VAR_BOOL;
3613 	rettv->vval.v_number = VVAL_FALSE;
3614 	*arg += 7;
3615     }
3616     else if (STRNCMP(*arg, "v:null", 6) == 0)
3617     {
3618 	rettv->v_type = VAR_SPECIAL;
3619 	rettv->vval.v_number = VVAL_NULL;
3620 	*arg += 6;
3621     }
3622     else if (STRNCMP(*arg, "v:none", 6) == 0)
3623     {
3624 	rettv->v_type = VAR_SPECIAL;
3625 	rettv->vval.v_number = VVAL_NONE;
3626 	*arg += 6;
3627     }
3628 }
3629 
3630     exprtype_T
3631 get_compare_type(char_u *p, int *len, int *type_is)
3632 {
3633     exprtype_T	type = EXPR_UNKNOWN;
3634     int		i;
3635 
3636     switch (p[0])
3637     {
3638 	case '=':   if (p[1] == '=')
3639 			type = EXPR_EQUAL;
3640 		    else if (p[1] == '~')
3641 			type = EXPR_MATCH;
3642 		    break;
3643 	case '!':   if (p[1] == '=')
3644 			type = EXPR_NEQUAL;
3645 		    else if (p[1] == '~')
3646 			type = EXPR_NOMATCH;
3647 		    break;
3648 	case '>':   if (p[1] != '=')
3649 		    {
3650 			type = EXPR_GREATER;
3651 			*len = 1;
3652 		    }
3653 		    else
3654 			type = EXPR_GEQUAL;
3655 		    break;
3656 	case '<':   if (p[1] != '=')
3657 		    {
3658 			type = EXPR_SMALLER;
3659 			*len = 1;
3660 		    }
3661 		    else
3662 			type = EXPR_SEQUAL;
3663 		    break;
3664 	case 'i':   if (p[1] == 's')
3665 		    {
3666 			// "is" and "isnot"; but not a prefix of a name
3667 			if (p[2] == 'n' && p[3] == 'o' && p[4] == 't')
3668 			    *len = 5;
3669 			i = p[*len];
3670 			if (!isalnum(i) && i != '_')
3671 			{
3672 			    type = *len == 2 ? EXPR_IS : EXPR_ISNOT;
3673 			    *type_is = TRUE;
3674 			}
3675 		    }
3676 		    break;
3677     }
3678     return type;
3679 }
3680 
3681 /*
3682  * Skip over an expression, ignoring most errors.
3683  */
3684     static void
3685 skip_expr_cctx(char_u **arg, cctx_T *cctx)
3686 {
3687     evalarg_T	evalarg;
3688 
3689     CLEAR_FIELD(evalarg);
3690     evalarg.eval_cctx = cctx;
3691     skip_expr(arg, &evalarg);
3692 }
3693 
3694 /*
3695  * Compile code to apply '-', '+' and '!'.
3696  * When "numeric_only" is TRUE do not apply '!'.
3697  */
3698     static int
3699 compile_leader(cctx_T *cctx, int numeric_only, char_u *start, char_u **end)
3700 {
3701     char_u	*p = *end;
3702 
3703     // this works from end to start
3704     while (p > start)
3705     {
3706 	--p;
3707 	while (VIM_ISWHITE(*p))
3708 	    --p;
3709 	if (*p == '-' || *p == '+')
3710 	{
3711 	    int	    negate = *p == '-';
3712 	    isn_T   *isn;
3713 
3714 	    // TODO: check type
3715 	    while (p > start && (p[-1] == '-' || p[-1] == '+'))
3716 	    {
3717 		--p;
3718 		if (*p == '-')
3719 		    negate = !negate;
3720 	    }
3721 	    // only '-' has an effect, for '+' we only check the type
3722 	    if (negate)
3723 		isn = generate_instr(cctx, ISN_NEGATENR);
3724 	    else
3725 		isn = generate_instr(cctx, ISN_CHECKNR);
3726 	    if (isn == NULL)
3727 		return FAIL;
3728 	}
3729 	else if (numeric_only)
3730 	{
3731 	    ++p;
3732 	    break;
3733 	}
3734 	else
3735 	{
3736 	    int  invert = *p == '!';
3737 
3738 	    while (p > start && (p[-1] == '!' || VIM_ISWHITE(p[-1])))
3739 	    {
3740 		if (p[-1] == '!')
3741 		    invert = !invert;
3742 		--p;
3743 	    }
3744 	    if (generate_2BOOL(cctx, invert) == FAIL)
3745 		return FAIL;
3746 	}
3747     }
3748     *end = p;
3749     return OK;
3750 }
3751 
3752 /*
3753  * Compile "(expression)": recursive!
3754  * Return FAIL/OK.
3755  */
3756     static int
3757 compile_parenthesis(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3758 {
3759     int	    ret;
3760     char_u  *p = *arg + 1;
3761 
3762     if (may_get_next_line_error(p, arg, cctx) == FAIL)
3763 	return FAIL;
3764     if (ppconst->pp_used <= PPSIZE - 10)
3765     {
3766 	ret = compile_expr1(arg, cctx, ppconst);
3767     }
3768     else
3769     {
3770 	// Not enough space in ppconst, flush constants.
3771 	if (generate_ppconst(cctx, ppconst) == FAIL)
3772 	    return FAIL;
3773 	ret = compile_expr0(arg, cctx);
3774     }
3775     if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
3776 	return FAIL;
3777     if (**arg == ')')
3778 	++*arg;
3779     else if (ret == OK)
3780     {
3781 	emsg(_(e_missing_close));
3782 	ret = FAIL;
3783     }
3784     return ret;
3785 }
3786 
3787 /*
3788  * Compile whatever comes after "name" or "name()".
3789  * Advances "*arg" only when something was recognized.
3790  */
3791     static int
3792 compile_subscript(
3793 	char_u **arg,
3794 	cctx_T *cctx,
3795 	char_u *start_leader,
3796 	char_u **end_leader,
3797 	ppconst_T *ppconst)
3798 {
3799     char_u	*name_start = *end_leader;
3800 
3801     for (;;)
3802     {
3803 	char_u *p = skipwhite(*arg);
3804 
3805 	if (*p == NUL || (VIM_ISWHITE(**arg) && vim9_comment_start(p)))
3806 	{
3807 	    char_u *next = peek_next_line_from_context(cctx);
3808 
3809 	    // If a following line starts with "->{" or "->X" advance to that
3810 	    // line, so that a line break before "->" is allowed.
3811 	    // Also if a following line starts with ".x".
3812 	    if (next != NULL &&
3813 		    ((next[0] == '-' && next[1] == '>'
3814 				 && (next[2] == '{' || ASCII_ISALPHA(next[2])))
3815 		    || (next[0] == '.' && eval_isdictc(next[1]))))
3816 	    {
3817 		next = next_line_from_context(cctx, TRUE);
3818 		if (next == NULL)
3819 		    return FAIL;
3820 		*arg = next;
3821 		p = skipwhite(*arg);
3822 	    }
3823 	}
3824 
3825 	// Do not skip over white space to find the "(", "execute 'x' ()" is
3826 	// not a function call.
3827 	if (**arg == '(')
3828 	{
3829 	    garray_T    *stack = &cctx->ctx_type_stack;
3830 	    type_T	*type;
3831 	    int		argcount = 0;
3832 
3833 	    if (generate_ppconst(cctx, ppconst) == FAIL)
3834 		return FAIL;
3835 	    ppconst->pp_is_const = FALSE;
3836 
3837 	    // funcref(arg)
3838 	    type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
3839 
3840 	    *arg = skipwhite(p + 1);
3841 	    if (compile_arguments(arg, cctx, &argcount) == FAIL)
3842 		return FAIL;
3843 	    if (generate_PCALL(cctx, argcount, name_start, type, TRUE) == FAIL)
3844 		return FAIL;
3845 	}
3846 	else if (*p == '-' && p[1] == '>')
3847 	{
3848 	    char_u *pstart = p;
3849 
3850 	    if (generate_ppconst(cctx, ppconst) == FAIL)
3851 		return FAIL;
3852 	    ppconst->pp_is_const = FALSE;
3853 
3854 	    // something->method()
3855 	    // Apply the '!', '-' and '+' first:
3856 	    //   -1.0->func() works like (-1.0)->func()
3857 	    if (compile_leader(cctx, TRUE, start_leader, end_leader) == FAIL)
3858 		return FAIL;
3859 
3860 	    p += 2;
3861 	    *arg = skipwhite(p);
3862 	    // No line break supported right after "->".
3863 	    if (**arg == '(')
3864 	    {
3865 		int	    argcount = 1;
3866 		char_u	    *expr;
3867 		garray_T    *stack;
3868 		type_T	    *type;
3869 
3870 		// Funcref call:  list->(Refs[2])(arg)
3871 		// or lambda:	  list->((arg) => expr)(arg)
3872 		// Fist compile the arguments.
3873 		expr = *arg;
3874 		*arg = skipwhite(*arg + 1);
3875 		skip_expr_cctx(arg, cctx);
3876 		*arg = skipwhite(*arg);
3877 		if (**arg != ')')
3878 		{
3879 		    semsg(_(e_missing_paren), *arg);
3880 		    return FAIL;
3881 		}
3882 		++*arg;
3883 		if (**arg != '(')
3884 		{
3885 		    if (*skipwhite(*arg) == '(')
3886 			emsg(_(e_nowhitespace));
3887 		    else
3888 			semsg(_(e_missing_paren), *arg);
3889 		    return FAIL;
3890 		}
3891 
3892 		*arg = skipwhite(*arg + 1);
3893 		if (compile_arguments(arg, cctx, &argcount) == FAIL)
3894 		    return FAIL;
3895 
3896 		// Compile the function expression.
3897 		if (compile_parenthesis(&expr, cctx, ppconst) == FAIL)
3898 		    return FAIL;
3899 
3900 		stack = &cctx->ctx_type_stack;
3901 		type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
3902 		if (generate_PCALL(cctx, argcount,
3903 				(char_u *)"[expression]", type, FALSE) == FAIL)
3904 		    return FAIL;
3905 	    }
3906 	    else
3907 	    {
3908 		// method call:  list->method()
3909 		p = *arg;
3910 		if (!eval_isnamec1(*p))
3911 		{
3912 		    semsg(_(e_trailing_arg), pstart);
3913 		    return FAIL;
3914 		}
3915 		if (ASCII_ISALPHA(*p) && p[1] == ':')
3916 		    p += 2;
3917 		for ( ; eval_isnamec(*p); ++p)
3918 		    ;
3919 		if (*p != '(')
3920 		{
3921 		    semsg(_(e_missing_paren), *arg);
3922 		    return FAIL;
3923 		}
3924 		// TODO: base value may not be the first argument
3925 		if (compile_call(arg, p - *arg, cctx, ppconst, 1) == FAIL)
3926 		    return FAIL;
3927 	    }
3928 	}
3929 	else if (**arg == '[')
3930 	{
3931 	    garray_T	*stack = &cctx->ctx_type_stack;
3932 	    type_T	**typep;
3933 	    type_T	*valtype;
3934 	    vartype_T	vtype;
3935 	    int		is_slice = FALSE;
3936 
3937 	    // list index: list[123]
3938 	    // dict member: dict[key]
3939 	    // string index: text[123]
3940 	    // TODO: blob index
3941 	    // TODO: more arguments
3942 	    // TODO: recognize list or dict at runtime
3943 	    if (generate_ppconst(cctx, ppconst) == FAIL)
3944 		return FAIL;
3945 	    ppconst->pp_is_const = FALSE;
3946 
3947 	    ++p;
3948 	    if (may_get_next_line_error(p, arg, cctx) == FAIL)
3949 		return FAIL;
3950 	    if (**arg == ':')
3951 	    {
3952 		// missing first index is equal to zero
3953 		generate_PUSHNR(cctx, 0);
3954 	    }
3955 	    else
3956 	    {
3957 		if (compile_expr0(arg, cctx) == FAIL)
3958 		    return FAIL;
3959 		if (**arg == ':')
3960 		{
3961 		    semsg(_(e_white_space_required_before_and_after_str_at_str),
3962 								    ":", *arg);
3963 		    return FAIL;
3964 		}
3965 		if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
3966 		    return FAIL;
3967 		*arg = skipwhite(*arg);
3968 	    }
3969 	    if (**arg == ':')
3970 	    {
3971 		is_slice = TRUE;
3972 		++*arg;
3973 		if (!IS_WHITE_OR_NUL(**arg) && **arg != ']')
3974 		{
3975 		    semsg(_(e_white_space_required_before_and_after_str_at_str),
3976 								    ":", *arg);
3977 		    return FAIL;
3978 		}
3979 		if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
3980 		    return FAIL;
3981 		if (**arg == ']')
3982 		    // missing second index is equal to end of string
3983 		    generate_PUSHNR(cctx, -1);
3984 		else
3985 		{
3986 		    if (compile_expr0(arg, cctx) == FAIL)
3987 			return FAIL;
3988 		    if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
3989 			return FAIL;
3990 		    *arg = skipwhite(*arg);
3991 		}
3992 	    }
3993 
3994 	    if (**arg != ']')
3995 	    {
3996 		emsg(_(e_missbrac));
3997 		return FAIL;
3998 	    }
3999 	    *arg = *arg + 1;
4000 
4001 	    // We can index a list and a dict.  If we don't know the type
4002 	    // we can use the index value type.
4003 	    // TODO: If we don't know use an instruction to figure it out at
4004 	    // runtime.
4005 	    typep = ((type_T **)stack->ga_data) + stack->ga_len
4006 							  - (is_slice ? 3 : 2);
4007 	    vtype = (*typep)->tt_type;
4008 	    valtype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4009 	    // If the index is a string, the variable must be a Dict.
4010 	    if (*typep == &t_any && valtype == &t_string)
4011 		vtype = VAR_DICT;
4012 	    if (vtype == VAR_STRING || vtype == VAR_LIST || vtype == VAR_BLOB)
4013 	    {
4014 		if (need_type(valtype, &t_number, -1, 0, cctx,
4015 							 FALSE, FALSE) == FAIL)
4016 		    return FAIL;
4017 		if (is_slice)
4018 		{
4019 		    valtype = ((type_T **)stack->ga_data)[stack->ga_len - 2];
4020 		    if (need_type(valtype, &t_number, -2, 0, cctx,
4021 							 FALSE, FALSE) == FAIL)
4022 			return FAIL;
4023 		}
4024 	    }
4025 
4026 	    if (vtype == VAR_DICT)
4027 	    {
4028 		if (is_slice)
4029 		{
4030 		    emsg(_(e_cannot_slice_dictionary));
4031 		    return FAIL;
4032 		}
4033 		if ((*typep)->tt_type == VAR_DICT)
4034 		{
4035 		    *typep = (*typep)->tt_member;
4036 		    if (*typep == &t_unknown)
4037 			// empty dict was used
4038 			*typep = &t_any;
4039 		}
4040 		else
4041 		{
4042 		    if (need_type(*typep, &t_dict_any, -2, 0, cctx,
4043 							 FALSE, FALSE) == FAIL)
4044 			return FAIL;
4045 		    *typep = &t_any;
4046 		}
4047 		if (may_generate_2STRING(-1, cctx) == FAIL)
4048 		    return FAIL;
4049 		if (generate_instr_drop(cctx, ISN_MEMBER, 1) == FAIL)
4050 		    return FAIL;
4051 	    }
4052 	    else if (vtype == VAR_STRING)
4053 	    {
4054 		*typep = &t_string;
4055 		if ((is_slice
4056 			? generate_instr_drop(cctx, ISN_STRSLICE, 2)
4057 			: generate_instr_drop(cctx, ISN_STRINDEX, 1)) == FAIL)
4058 		    return FAIL;
4059 	    }
4060 	    else if (vtype == VAR_BLOB)
4061 	    {
4062 		emsg("Sorry, blob index and slice not implemented yet");
4063 		return FAIL;
4064 	    }
4065 	    else if (vtype == VAR_LIST || *typep == &t_any)
4066 	    {
4067 		if (is_slice)
4068 		{
4069 		    if (generate_instr_drop(cctx,
4070 			     vtype == VAR_LIST ?  ISN_LISTSLICE : ISN_ANYSLICE,
4071 								    2) == FAIL)
4072 			return FAIL;
4073 		}
4074 		else
4075 		{
4076 		    if ((*typep)->tt_type == VAR_LIST)
4077 		    {
4078 			*typep = (*typep)->tt_member;
4079 			if (*typep == &t_unknown)
4080 			    // empty list was used
4081 			    *typep = &t_any;
4082 		    }
4083 		    if (generate_instr_drop(cctx,
4084 			     vtype == VAR_LIST ?  ISN_LISTINDEX : ISN_ANYINDEX,
4085 								    1) == FAIL)
4086 			return FAIL;
4087 		}
4088 	    }
4089 	    else
4090 	    {
4091 		emsg(_(e_string_list_dict_or_blob_required));
4092 		return FAIL;
4093 	    }
4094 	}
4095 	else if (*p == '.' && p[1] != '.')
4096 	{
4097 	    // dictionary member: dict.name
4098 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4099 		return FAIL;
4100 	    ppconst->pp_is_const = FALSE;
4101 
4102 	    *arg = p + 1;
4103 	    if (may_get_next_line(*arg, arg, cctx) == FAIL)
4104 	    {
4105 		emsg(_(e_missing_name_after_dot));
4106 		return FAIL;
4107 	    }
4108 	    p = *arg;
4109 	    if (eval_isdictc(*p))
4110 		while (eval_isnamec(*p))
4111 		    MB_PTR_ADV(p);
4112 	    if (p == *arg)
4113 	    {
4114 		semsg(_(e_syntax_error_at_str), *arg);
4115 		return FAIL;
4116 	    }
4117 	    if (generate_STRINGMEMBER(cctx, *arg, p - *arg) == FAIL)
4118 		return FAIL;
4119 	    *arg = p;
4120 	}
4121 	else
4122 	    break;
4123     }
4124 
4125     // TODO - see handle_subscript():
4126     // Turn "dict.Func" into a partial for "Func" bound to "dict".
4127     // Don't do this when "Func" is already a partial that was bound
4128     // explicitly (pt_auto is FALSE).
4129 
4130     return OK;
4131 }
4132 
4133 /*
4134  * Compile an expression at "*arg" and add instructions to "cctx->ctx_instr".
4135  * "arg" is advanced until after the expression, skipping white space.
4136  *
4137  * If the value is a constant "ppconst->pp_used" will be non-zero.
4138  * Before instructions are generated, any values in "ppconst" will generated.
4139  *
4140  * This is the compiling equivalent of eval1(), eval2(), etc.
4141  */
4142 
4143 /*
4144  *  number		number constant
4145  *  0zFFFFFFFF		Blob constant
4146  *  "string"		string constant
4147  *  'string'		literal string constant
4148  *  &option-name	option value
4149  *  @r			register contents
4150  *  identifier		variable value
4151  *  function()		function call
4152  *  $VAR		environment variable
4153  *  (expression)	nested expression
4154  *  [expr, expr]	List
4155  *  {key: val, [key]: val}   Dictionary
4156  *
4157  *  Also handle:
4158  *  ! in front		logical NOT
4159  *  - in front		unary minus
4160  *  + in front		unary plus (ignored)
4161  *  trailing (arg)	funcref/partial call
4162  *  trailing []		subscript in String or List
4163  *  trailing .name	entry in Dictionary
4164  *  trailing ->name()	method call
4165  */
4166     static int
4167 compile_expr7(
4168 	char_u **arg,
4169 	cctx_T *cctx,
4170 	ppconst_T *ppconst)
4171 {
4172     char_u	*start_leader, *end_leader;
4173     int		ret = OK;
4174     typval_T	*rettv = &ppconst->pp_tv[ppconst->pp_used];
4175     int		used_before = ppconst->pp_used;
4176 
4177     ppconst->pp_is_const = FALSE;
4178 
4179     /*
4180      * Skip '!', '-' and '+' characters.  They are handled later.
4181      */
4182     start_leader = *arg;
4183     if (eval_leader(arg, TRUE) == FAIL)
4184 	return FAIL;
4185     end_leader = *arg;
4186 
4187     rettv->v_type = VAR_UNKNOWN;
4188     switch (**arg)
4189     {
4190 	/*
4191 	 * Number constant.
4192 	 */
4193 	case '0':	// also for blob starting with 0z
4194 	case '1':
4195 	case '2':
4196 	case '3':
4197 	case '4':
4198 	case '5':
4199 	case '6':
4200 	case '7':
4201 	case '8':
4202 	case '9':
4203 	case '.':   if (eval_number(arg, rettv, TRUE, FALSE) == FAIL)
4204 			return FAIL;
4205 		    // Apply "-" and "+" just before the number now, right to
4206 		    // left.  Matters especially when "->" follows.  Stops at
4207 		    // '!'.
4208 		    if (apply_leader(rettv, TRUE,
4209 					    start_leader, &end_leader) == FAIL)
4210 		    {
4211 			clear_tv(rettv);
4212 			return FAIL;
4213 		    }
4214 		    break;
4215 
4216 	/*
4217 	 * String constant: "string".
4218 	 */
4219 	case '"':   if (eval_string(arg, rettv, TRUE) == FAIL)
4220 			return FAIL;
4221 		    break;
4222 
4223 	/*
4224 	 * Literal string constant: 'str''ing'.
4225 	 */
4226 	case '\'':  if (eval_lit_string(arg, rettv, TRUE) == FAIL)
4227 			return FAIL;
4228 		    break;
4229 
4230 	/*
4231 	 * Constant Vim variable.
4232 	 */
4233 	case 'v':   get_vim_constant(arg, rettv);
4234 		    ret = NOTDONE;
4235 		    break;
4236 
4237 	/*
4238 	 * "true" constant
4239 	 */
4240 	case 't':   if (STRNCMP(*arg, "true", 4) == 0
4241 						   && !eval_isnamec((*arg)[4]))
4242 		    {
4243 			*arg += 4;
4244 			rettv->v_type = VAR_BOOL;
4245 			rettv->vval.v_number = VVAL_TRUE;
4246 		    }
4247 		    else
4248 			ret = NOTDONE;
4249 		    break;
4250 
4251 	/*
4252 	 * "false" constant
4253 	 */
4254 	case 'f':   if (STRNCMP(*arg, "false", 5) == 0
4255 						   && !eval_isnamec((*arg)[5]))
4256 		    {
4257 			*arg += 5;
4258 			rettv->v_type = VAR_BOOL;
4259 			rettv->vval.v_number = VVAL_FALSE;
4260 		    }
4261 		    else
4262 			ret = NOTDONE;
4263 		    break;
4264 
4265 	/*
4266 	 * "null" constant
4267 	 */
4268 	case 'n':   if (STRNCMP(*arg, "null", 4) == 0
4269 						   && !eval_isnamec((*arg)[4]))
4270 		    {
4271 			*arg += 4;
4272 			rettv->v_type = VAR_SPECIAL;
4273 			rettv->vval.v_number = VVAL_NULL;
4274 		    }
4275 		    else
4276 			ret = NOTDONE;
4277 		    break;
4278 
4279 	/*
4280 	 * List: [expr, expr]
4281 	 */
4282 	case '[':   if (generate_ppconst(cctx, ppconst) == FAIL)
4283 			return FAIL;
4284 		    ret = compile_list(arg, cctx, ppconst);
4285 		    break;
4286 
4287 	/*
4288 	 * Dictionary: {'key': val, 'key': val}
4289 	 */
4290 	case '{':   if (generate_ppconst(cctx, ppconst) == FAIL)
4291 			return FAIL;
4292 		    ret = compile_dict(arg, cctx, ppconst);
4293 		    break;
4294 
4295 	/*
4296 	 * Option value: &name
4297 	 */
4298 	case '&':	if (generate_ppconst(cctx, ppconst) == FAIL)
4299 			    return FAIL;
4300 			ret = compile_get_option(arg, cctx);
4301 			break;
4302 
4303 	/*
4304 	 * Environment variable: $VAR.
4305 	 */
4306 	case '$':	if (generate_ppconst(cctx, ppconst) == FAIL)
4307 			    return FAIL;
4308 			ret = compile_get_env(arg, cctx);
4309 			break;
4310 
4311 	/*
4312 	 * Register contents: @r.
4313 	 */
4314 	case '@':	if (generate_ppconst(cctx, ppconst) == FAIL)
4315 			    return FAIL;
4316 			ret = compile_get_register(arg, cctx);
4317 			break;
4318 	/*
4319 	 * nested expression: (expression).
4320 	 * lambda: (arg, arg) => expr
4321 	 * funcref: (arg, arg) => { statement }
4322 	 */
4323 	case '(':   // if compile_lambda returns NOTDONE then it must be (expr)
4324 		    ret = compile_lambda(arg, cctx);
4325 		    if (ret == NOTDONE)
4326 			ret = compile_parenthesis(arg, cctx, ppconst);
4327 		    break;
4328 
4329 	default:    ret = NOTDONE;
4330 		    break;
4331     }
4332     if (ret == FAIL)
4333 	return FAIL;
4334 
4335     if (rettv->v_type != VAR_UNKNOWN && used_before == ppconst->pp_used)
4336     {
4337 	if (cctx->ctx_skip == SKIP_YES)
4338 	    clear_tv(rettv);
4339 	else
4340 	    // A constant expression can possibly be handled compile time,
4341 	    // return the value instead of generating code.
4342 	    ++ppconst->pp_used;
4343     }
4344     else if (ret == NOTDONE)
4345     {
4346 	char_u	    *p;
4347 	int	    r;
4348 
4349 	if (!eval_isnamec1(**arg))
4350 	{
4351 	    if (!vim9_bad_comment(*arg))
4352 	    {
4353 		if (ends_excmd(*skipwhite(*arg)))
4354 		    semsg(_(e_empty_expression_str), *arg);
4355 		else
4356 		    semsg(_(e_name_expected_str), *arg);
4357 	    }
4358 	    return FAIL;
4359 	}
4360 
4361 	// "name" or "name()"
4362 	p = to_name_end(*arg, TRUE);
4363 	if (*p == '(')
4364 	{
4365 	    r = compile_call(arg, p - *arg, cctx, ppconst, 0);
4366 	}
4367 	else
4368 	{
4369 	    if (generate_ppconst(cctx, ppconst) == FAIL)
4370 		return FAIL;
4371 	    r = compile_load(arg, p, cctx, TRUE, TRUE);
4372 	}
4373 	if (r == FAIL)
4374 	    return FAIL;
4375     }
4376 
4377     // Handle following "[]", ".member", etc.
4378     // Then deal with prefixed '-', '+' and '!', if not done already.
4379     if (compile_subscript(arg, cctx, start_leader, &end_leader,
4380 							     ppconst) == FAIL)
4381 	return FAIL;
4382     if (ppconst->pp_used > 0)
4383     {
4384 	// apply the '!', '-' and '+' before the constant
4385 	rettv = &ppconst->pp_tv[ppconst->pp_used - 1];
4386 	if (apply_leader(rettv, FALSE, start_leader, &end_leader) == FAIL)
4387 	    return FAIL;
4388 	return OK;
4389     }
4390     if (compile_leader(cctx, FALSE, start_leader, &end_leader) == FAIL)
4391 	return FAIL;
4392     return OK;
4393 }
4394 
4395 /*
4396  * Give the "white on both sides" error, taking the operator from "p[len]".
4397  */
4398     void
4399 error_white_both(char_u *op, int len)
4400 {
4401     char_u	buf[10];
4402 
4403     vim_strncpy(buf, op, len);
4404     semsg(_(e_white_space_required_before_and_after_str_at_str), buf, op);
4405 }
4406 
4407 /*
4408  * <type>expr7: runtime type check / conversion
4409  */
4410     static int
4411 compile_expr7t(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4412 {
4413     type_T *want_type = NULL;
4414 
4415     // Recognize <type>
4416     if (**arg == '<' && eval_isnamec1((*arg)[1]))
4417     {
4418 	++*arg;
4419 	want_type = parse_type(arg, cctx->ctx_type_list, TRUE);
4420 	if (want_type == NULL)
4421 	    return FAIL;
4422 
4423 	if (**arg != '>')
4424 	{
4425 	    if (*skipwhite(*arg) == '>')
4426 		semsg(_(e_no_white_space_allowed_before_str_str), ">", *arg);
4427 	    else
4428 		emsg(_(e_missing_gt));
4429 	    return FAIL;
4430 	}
4431 	++*arg;
4432 	if (may_get_next_line_error(*arg, arg, cctx) == FAIL)
4433 	    return FAIL;
4434     }
4435 
4436     if (compile_expr7(arg, cctx, ppconst) == FAIL)
4437 	return FAIL;
4438 
4439     if (want_type != NULL)
4440     {
4441 	garray_T    *stack = &cctx->ctx_type_stack;
4442 	type_T	    *actual;
4443 	where_T	    where;
4444 
4445 	generate_ppconst(cctx, ppconst);
4446 	actual = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4447 	where.wt_index = 0;
4448 	where.wt_variable = FALSE;
4449 	if (check_type(want_type, actual, FALSE, where) == FAIL)
4450 	{
4451 	    if (need_type(actual, want_type, -1, 0, cctx, FALSE, FALSE) == FAIL)
4452 		return FAIL;
4453 	}
4454     }
4455 
4456     return OK;
4457 }
4458 
4459 /*
4460  *	*	number multiplication
4461  *	/	number division
4462  *	%	number modulo
4463  */
4464     static int
4465 compile_expr6(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4466 {
4467     char_u	*op;
4468     char_u	*next;
4469     int		ppconst_used = ppconst->pp_used;
4470 
4471     // get the first expression
4472     if (compile_expr7t(arg, cctx, ppconst) == FAIL)
4473 	return FAIL;
4474 
4475     /*
4476      * Repeat computing, until no "*", "/" or "%" is following.
4477      */
4478     for (;;)
4479     {
4480 	op = may_peek_next_line(cctx, *arg, &next);
4481 	if (*op != '*' && *op != '/' && *op != '%')
4482 	    break;
4483 	if (next != NULL)
4484 	{
4485 	    *arg = next_line_from_context(cctx, TRUE);
4486 	    op = skipwhite(*arg);
4487 	}
4488 
4489 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(op[1]))
4490 	{
4491 	    error_white_both(op, 1);
4492 	    return FAIL;
4493 	}
4494 	if (may_get_next_line_error(op + 1, arg, cctx) == FAIL)
4495 	    return FAIL;
4496 
4497 	// get the second expression
4498 	if (compile_expr7t(arg, cctx, ppconst) == FAIL)
4499 	    return FAIL;
4500 
4501 	if (ppconst->pp_used == ppconst_used + 2
4502 		&& ppconst->pp_tv[ppconst_used].v_type == VAR_NUMBER
4503 		&& ppconst->pp_tv[ppconst_used + 1].v_type == VAR_NUMBER)
4504 	{
4505 	    typval_T	    *tv1 = &ppconst->pp_tv[ppconst_used];
4506 	    typval_T	    *tv2 = &ppconst->pp_tv[ppconst_used + 1];
4507 	    varnumber_T	    res = 0;
4508 	    int		    failed = FALSE;
4509 
4510 	    // both are numbers: compute the result
4511 	    switch (*op)
4512 	    {
4513 		case '*': res = tv1->vval.v_number * tv2->vval.v_number;
4514 			  break;
4515 		case '/': res = num_divide(tv1->vval.v_number,
4516 						  tv2->vval.v_number, &failed);
4517 			  break;
4518 		case '%': res = num_modulus(tv1->vval.v_number,
4519 						  tv2->vval.v_number, &failed);
4520 			  break;
4521 	    }
4522 	    if (failed)
4523 		return FAIL;
4524 	    tv1->vval.v_number = res;
4525 	    --ppconst->pp_used;
4526 	}
4527 	else
4528 	{
4529 	    generate_ppconst(cctx, ppconst);
4530 	    generate_two_op(cctx, op);
4531 	}
4532     }
4533 
4534     return OK;
4535 }
4536 
4537 /*
4538  *      +	number addition or list/blobl concatenation
4539  *      -	number subtraction
4540  *      ..	string concatenation
4541  */
4542     static int
4543 compile_expr5(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4544 {
4545     char_u	*op;
4546     char_u	*next;
4547     int		oplen;
4548     int		ppconst_used = ppconst->pp_used;
4549 
4550     // get the first variable
4551     if (compile_expr6(arg, cctx, ppconst) == FAIL)
4552 	return FAIL;
4553 
4554     /*
4555      * Repeat computing, until no "+", "-" or ".." is following.
4556      */
4557     for (;;)
4558     {
4559 	op = may_peek_next_line(cctx, *arg, &next);
4560 	if (*op != '+' && *op != '-' && !(*op == '.' && *(op + 1) == '.'))
4561 	    break;
4562 	oplen = (*op == '.' ? 2 : 1);
4563 	if (next != NULL)
4564 	{
4565 	    *arg = next_line_from_context(cctx, TRUE);
4566 	    op = skipwhite(*arg);
4567 	}
4568 
4569 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(op[oplen]))
4570 	{
4571 	    error_white_both(op, oplen);
4572 	    return FAIL;
4573 	}
4574 
4575 	if (may_get_next_line_error(op + oplen, arg, cctx) == FAIL)
4576 	    return FAIL;
4577 
4578 	// get the second expression
4579 	if (compile_expr6(arg, cctx, ppconst) == FAIL)
4580 	    return FAIL;
4581 
4582 	if (ppconst->pp_used == ppconst_used + 2
4583 		&& (*op == '.'
4584 		    ? (ppconst->pp_tv[ppconst_used].v_type == VAR_STRING
4585 		    && ppconst->pp_tv[ppconst_used + 1].v_type == VAR_STRING)
4586 		    : (ppconst->pp_tv[ppconst_used].v_type == VAR_NUMBER
4587 		    && ppconst->pp_tv[ppconst_used + 1].v_type == VAR_NUMBER)))
4588 	{
4589 	    typval_T *tv1 = &ppconst->pp_tv[ppconst_used];
4590 	    typval_T *tv2 = &ppconst->pp_tv[ppconst_used + 1];
4591 
4592 	    // concat/subtract/add constant numbers
4593 	    if (*op == '+')
4594 		tv1->vval.v_number = tv1->vval.v_number + tv2->vval.v_number;
4595 	    else if (*op == '-')
4596 		tv1->vval.v_number = tv1->vval.v_number - tv2->vval.v_number;
4597 	    else
4598 	    {
4599 		// concatenate constant strings
4600 		char_u *s1 = tv1->vval.v_string;
4601 		char_u *s2 = tv2->vval.v_string;
4602 		size_t len1 = STRLEN(s1);
4603 
4604 		tv1->vval.v_string = alloc((int)(len1 + STRLEN(s2) + 1));
4605 		if (tv1->vval.v_string == NULL)
4606 		{
4607 		    clear_ppconst(ppconst);
4608 		    return FAIL;
4609 		}
4610 		mch_memmove(tv1->vval.v_string, s1, len1);
4611 		STRCPY(tv1->vval.v_string + len1, s2);
4612 		vim_free(s1);
4613 		vim_free(s2);
4614 	    }
4615 	    --ppconst->pp_used;
4616 	}
4617 	else
4618 	{
4619 	    generate_ppconst(cctx, ppconst);
4620 	    ppconst->pp_is_const = FALSE;
4621 	    if (*op == '.')
4622 	    {
4623 		if (may_generate_2STRING(-2, cctx) == FAIL
4624 			|| may_generate_2STRING(-1, cctx) == FAIL)
4625 		    return FAIL;
4626 		generate_instr_drop(cctx, ISN_CONCAT, 1);
4627 	    }
4628 	    else
4629 		generate_two_op(cctx, op);
4630 	}
4631     }
4632 
4633     return OK;
4634 }
4635 
4636 /*
4637  * expr5a == expr5b
4638  * expr5a =~ expr5b
4639  * expr5a != expr5b
4640  * expr5a !~ expr5b
4641  * expr5a > expr5b
4642  * expr5a >= expr5b
4643  * expr5a < expr5b
4644  * expr5a <= expr5b
4645  * expr5a is expr5b
4646  * expr5a isnot expr5b
4647  *
4648  * Produces instructions:
4649  *	EVAL expr5a		Push result of "expr5a"
4650  *	EVAL expr5b		Push result of "expr5b"
4651  *	COMPARE			one of the compare instructions
4652  */
4653     static int
4654 compile_expr4(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4655 {
4656     exprtype_T	type = EXPR_UNKNOWN;
4657     char_u	*p;
4658     char_u	*next;
4659     int		len = 2;
4660     int		type_is = FALSE;
4661     int		ppconst_used = ppconst->pp_used;
4662 
4663     // get the first variable
4664     if (compile_expr5(arg, cctx, ppconst) == FAIL)
4665 	return FAIL;
4666 
4667     p = may_peek_next_line(cctx, *arg, &next);
4668     type = get_compare_type(p, &len, &type_is);
4669 
4670     /*
4671      * If there is a comparative operator, use it.
4672      */
4673     if (type != EXPR_UNKNOWN)
4674     {
4675 	int ic = FALSE;  // Default: do not ignore case
4676 
4677 	if (next != NULL)
4678 	{
4679 	    *arg = next_line_from_context(cctx, TRUE);
4680 	    p = skipwhite(*arg);
4681 	}
4682 	if (type_is && (p[len] == '?' || p[len] == '#'))
4683 	{
4684 	    semsg(_(e_invexpr2), *arg);
4685 	    return FAIL;
4686 	}
4687 	// extra question mark appended: ignore case
4688 	if (p[len] == '?')
4689 	{
4690 	    ic = TRUE;
4691 	    ++len;
4692 	}
4693 	// extra '#' appended: match case (ignored)
4694 	else if (p[len] == '#')
4695 	    ++len;
4696 	// nothing appended: match case
4697 
4698 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[len]))
4699 	{
4700 	    error_white_both(p, len);
4701 	    return FAIL;
4702 	}
4703 
4704 	// get the second variable
4705 	if (may_get_next_line_error(p + len, arg, cctx) == FAIL)
4706 	    return FAIL;
4707 
4708 	if (compile_expr5(arg, cctx, ppconst) == FAIL)
4709 	    return FAIL;
4710 
4711 	if (ppconst->pp_used == ppconst_used + 2)
4712 	{
4713 	    typval_T *	tv1 = &ppconst->pp_tv[ppconst->pp_used - 2];
4714 	    typval_T	*tv2 = &ppconst->pp_tv[ppconst->pp_used - 1];
4715 	    int		ret;
4716 
4717 	    // Both sides are a constant, compute the result now.
4718 	    // First check for a valid combination of types, this is more
4719 	    // strict than typval_compare().
4720 	    if (check_compare_types(type, tv1, tv2) == FAIL)
4721 		ret = FAIL;
4722 	    else
4723 	    {
4724 		ret = typval_compare(tv1, tv2, type, ic);
4725 		tv1->v_type = VAR_BOOL;
4726 		tv1->vval.v_number = tv1->vval.v_number
4727 						      ? VVAL_TRUE : VVAL_FALSE;
4728 		clear_tv(tv2);
4729 		--ppconst->pp_used;
4730 	    }
4731 	    return ret;
4732 	}
4733 
4734 	generate_ppconst(cctx, ppconst);
4735 	return generate_COMPARE(cctx, type, ic);
4736     }
4737 
4738     return OK;
4739 }
4740 
4741 static int compile_expr3(char_u **arg,  cctx_T *cctx, ppconst_T *ppconst);
4742 
4743 /*
4744  * Compile || or &&.
4745  */
4746     static int
4747 compile_and_or(
4748 	char_u **arg,
4749 	cctx_T	*cctx,
4750 	char	*op,
4751 	ppconst_T *ppconst,
4752 	int	ppconst_used UNUSED)
4753 {
4754     char_u	*next;
4755     char_u	*p = may_peek_next_line(cctx, *arg, &next);
4756     int		opchar = *op;
4757 
4758     if (p[0] == opchar && p[1] == opchar)
4759     {
4760 	garray_T	*instr = &cctx->ctx_instr;
4761 	garray_T	end_ga;
4762 
4763 	/*
4764 	 * Repeat until there is no following "||" or "&&"
4765 	 */
4766 	ga_init2(&end_ga, sizeof(int), 10);
4767 	while (p[0] == opchar && p[1] == opchar)
4768 	{
4769 	    if (next != NULL)
4770 	    {
4771 		*arg = next_line_from_context(cctx, TRUE);
4772 		p = skipwhite(*arg);
4773 	    }
4774 
4775 	    if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[2]))
4776 	    {
4777 		semsg(_(e_white_space_required_before_and_after_str_at_str),
4778 								     op, *arg);
4779 		return FAIL;
4780 	    }
4781 
4782 	    // TODO: use ppconst if the value is a constant and check
4783 	    // evaluating to bool
4784 	    generate_ppconst(cctx, ppconst);
4785 
4786 	    // Every part must evaluate to a bool.
4787 	    if (bool_on_stack(cctx) == FAIL)
4788 	    {
4789 		ga_clear(&end_ga);
4790 		return FAIL;
4791 	    }
4792 
4793 	    if (ga_grow(&end_ga, 1) == FAIL)
4794 	    {
4795 		ga_clear(&end_ga);
4796 		return FAIL;
4797 	    }
4798 	    *(((int *)end_ga.ga_data) + end_ga.ga_len) = instr->ga_len;
4799 	    ++end_ga.ga_len;
4800 	    generate_JUMP(cctx, opchar == '|'
4801 				 ?  JUMP_IF_COND_TRUE : JUMP_IF_COND_FALSE, 0);
4802 
4803 	    // eval the next expression
4804 	    if (may_get_next_line_error(p + 2, arg, cctx) == FAIL)
4805 	    {
4806 		ga_clear(&end_ga);
4807 		return FAIL;
4808 	    }
4809 
4810 	    if ((opchar == '|' ? compile_expr3(arg, cctx, ppconst)
4811 				  : compile_expr4(arg, cctx, ppconst)) == FAIL)
4812 	    {
4813 		ga_clear(&end_ga);
4814 		return FAIL;
4815 	    }
4816 
4817 	    p = may_peek_next_line(cctx, *arg, &next);
4818 	}
4819 	generate_ppconst(cctx, ppconst);
4820 
4821 	// Every part must evaluate to a bool.
4822 	if (bool_on_stack(cctx) == FAIL)
4823 	{
4824 	    ga_clear(&end_ga);
4825 	    return FAIL;
4826 	}
4827 
4828 	// Fill in the end label in all jumps.
4829 	while (end_ga.ga_len > 0)
4830 	{
4831 	    isn_T	*isn;
4832 
4833 	    --end_ga.ga_len;
4834 	    isn = ((isn_T *)instr->ga_data)
4835 				  + *(((int *)end_ga.ga_data) + end_ga.ga_len);
4836 	    isn->isn_arg.jump.jump_where = instr->ga_len;
4837 	}
4838 	ga_clear(&end_ga);
4839     }
4840 
4841     return OK;
4842 }
4843 
4844 /*
4845  * expr4a && expr4a && expr4a	    logical AND
4846  *
4847  * Produces instructions:
4848  *	EVAL expr4a		Push result of "expr4a"
4849  *	COND2BOOL		convert to bool if needed
4850  *	JUMP_IF_COND_FALSE end
4851  *	EVAL expr4b		Push result of "expr4b"
4852  *	JUMP_IF_COND_FALSE end
4853  *	EVAL expr4c		Push result of "expr4c"
4854  * end:
4855  */
4856     static int
4857 compile_expr3(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4858 {
4859     int		ppconst_used = ppconst->pp_used;
4860 
4861     // get the first variable
4862     if (compile_expr4(arg, cctx, ppconst) == FAIL)
4863 	return FAIL;
4864 
4865     // || and && work almost the same
4866     return compile_and_or(arg, cctx, "&&", ppconst, ppconst_used);
4867 }
4868 
4869 /*
4870  * expr3a || expr3b || expr3c	    logical OR
4871  *
4872  * Produces instructions:
4873  *	EVAL expr3a		Push result of "expr3a"
4874  *	COND2BOOL		convert to bool if needed
4875  *	JUMP_IF_COND_TRUE end
4876  *	EVAL expr3b		Push result of "expr3b"
4877  *	JUMP_IF_COND_TRUE end
4878  *	EVAL expr3c		Push result of "expr3c"
4879  * end:
4880  */
4881     static int
4882 compile_expr2(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4883 {
4884     int		ppconst_used = ppconst->pp_used;
4885 
4886     // eval the first expression
4887     if (compile_expr3(arg, cctx, ppconst) == FAIL)
4888 	return FAIL;
4889 
4890     // || and && work almost the same
4891     return compile_and_or(arg, cctx, "||", ppconst, ppconst_used);
4892 }
4893 
4894 /*
4895  * Toplevel expression: expr2 ? expr1a : expr1b
4896  * Produces instructions:
4897  *	EVAL expr2		Push result of "expr2"
4898  *      JUMP_IF_FALSE alt	jump if false
4899  *      EVAL expr1a
4900  *      JUMP_ALWAYS end
4901  * alt:	EVAL expr1b
4902  * end:
4903  *
4904  * Toplevel expression: expr2 ?? expr1
4905  * Produces instructions:
4906  *	EVAL expr2		    Push result of "expr2"
4907  *      JUMP_AND_KEEP_IF_TRUE end   jump if true
4908  *      EVAL expr1
4909  * end:
4910  */
4911     static int
4912 compile_expr1(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4913 {
4914     char_u	*p;
4915     int		ppconst_used = ppconst->pp_used;
4916     char_u	*next;
4917 
4918     // Ignore all kinds of errors when not producing code.
4919     if (cctx->ctx_skip == SKIP_YES)
4920     {
4921 	skip_expr_cctx(arg, cctx);
4922 	return OK;
4923     }
4924 
4925     // Evaluate the first expression.
4926     if (compile_expr2(arg, cctx, ppconst) == FAIL)
4927 	return FAIL;
4928 
4929     p = may_peek_next_line(cctx, *arg, &next);
4930     if (*p == '?')
4931     {
4932 	int		op_falsy = p[1] == '?';
4933 	garray_T	*instr = &cctx->ctx_instr;
4934 	garray_T	*stack = &cctx->ctx_type_stack;
4935 	int		alt_idx = instr->ga_len;
4936 	int		end_idx = 0;
4937 	isn_T		*isn;
4938 	type_T		*type1 = NULL;
4939 	int		has_const_expr = FALSE;
4940 	int		const_value = FALSE;
4941 	int		save_skip = cctx->ctx_skip;
4942 
4943 	if (next != NULL)
4944 	{
4945 	    *arg = next_line_from_context(cctx, TRUE);
4946 	    p = skipwhite(*arg);
4947 	}
4948 
4949 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[1 + op_falsy]))
4950 	{
4951 	    semsg(_(e_white_space_required_before_and_after_str_at_str),
4952 						  op_falsy ? "??" : "?", *arg);
4953 	    return FAIL;
4954 	}
4955 
4956 	if (ppconst->pp_used == ppconst_used + 1)
4957 	{
4958 	    // the condition is a constant, we know whether the ? or the :
4959 	    // expression is to be evaluated.
4960 	    has_const_expr = TRUE;
4961 	    if (op_falsy)
4962 		const_value = tv2bool(&ppconst->pp_tv[ppconst_used]);
4963 	    else
4964 	    {
4965 		int error = FALSE;
4966 
4967 		const_value = tv_get_bool_chk(&ppconst->pp_tv[ppconst_used],
4968 								       &error);
4969 		if (error)
4970 		    return FAIL;
4971 	    }
4972 	    cctx->ctx_skip = save_skip == SKIP_YES ||
4973 		 (op_falsy ? const_value : !const_value) ? SKIP_YES : SKIP_NOT;
4974 
4975 	    if (op_falsy && cctx->ctx_skip == SKIP_YES)
4976 		// "left ?? right" and "left" is truthy: produce "left"
4977 		generate_ppconst(cctx, ppconst);
4978 	    else
4979 	    {
4980 		clear_tv(&ppconst->pp_tv[ppconst_used]);
4981 		--ppconst->pp_used;
4982 	    }
4983 	}
4984 	else
4985 	{
4986 	    generate_ppconst(cctx, ppconst);
4987 	    if (op_falsy)
4988 		end_idx = instr->ga_len;
4989 	    generate_JUMP(cctx, op_falsy
4990 				   ? JUMP_AND_KEEP_IF_TRUE : JUMP_IF_FALSE, 0);
4991 	    if (op_falsy)
4992 		type1 = ((type_T **)stack->ga_data)[stack->ga_len];
4993 	}
4994 
4995 	// evaluate the second expression; any type is accepted
4996 	if (may_get_next_line_error(p + 1 + op_falsy, arg, cctx) == FAIL)
4997 	    return FAIL;
4998 	if (compile_expr1(arg, cctx, ppconst) == FAIL)
4999 	    return FAIL;
5000 
5001 	if (!has_const_expr)
5002 	{
5003 	    generate_ppconst(cctx, ppconst);
5004 
5005 	    if (!op_falsy)
5006 	    {
5007 		// remember the type and drop it
5008 		--stack->ga_len;
5009 		type1 = ((type_T **)stack->ga_data)[stack->ga_len];
5010 
5011 		end_idx = instr->ga_len;
5012 		generate_JUMP(cctx, JUMP_ALWAYS, 0);
5013 
5014 		// jump here from JUMP_IF_FALSE
5015 		isn = ((isn_T *)instr->ga_data) + alt_idx;
5016 		isn->isn_arg.jump.jump_where = instr->ga_len;
5017 	    }
5018 	}
5019 
5020 	if (!op_falsy)
5021 	{
5022 	    // Check for the ":".
5023 	    p = may_peek_next_line(cctx, *arg, &next);
5024 	    if (*p != ':')
5025 	    {
5026 		emsg(_(e_missing_colon));
5027 		return FAIL;
5028 	    }
5029 	    if (next != NULL)
5030 	    {
5031 		*arg = next_line_from_context(cctx, TRUE);
5032 		p = skipwhite(*arg);
5033 	    }
5034 
5035 	    if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[1]))
5036 	    {
5037 		semsg(_(e_white_space_required_before_and_after_str_at_str),
5038 								       ":", p);
5039 		return FAIL;
5040 	    }
5041 
5042 	    // evaluate the third expression
5043 	    if (has_const_expr)
5044 		cctx->ctx_skip = save_skip == SKIP_YES || const_value
5045 							 ? SKIP_YES : SKIP_NOT;
5046 	    if (may_get_next_line_error(p + 1, arg, cctx) == FAIL)
5047 		return FAIL;
5048 	    if (compile_expr1(arg, cctx, ppconst) == FAIL)
5049 		return FAIL;
5050 	}
5051 
5052 	if (!has_const_expr)
5053 	{
5054 	    type_T	**typep;
5055 
5056 	    generate_ppconst(cctx, ppconst);
5057 
5058 	    // If the types differ, the result has a more generic type.
5059 	    typep = ((type_T **)stack->ga_data) + stack->ga_len - 1;
5060 	    common_type(type1, *typep, typep, cctx->ctx_type_list);
5061 
5062 	    // jump here from JUMP_ALWAYS or JUMP_AND_KEEP_IF_TRUE
5063 	    isn = ((isn_T *)instr->ga_data) + end_idx;
5064 	    isn->isn_arg.jump.jump_where = instr->ga_len;
5065 	}
5066 
5067 	cctx->ctx_skip = save_skip;
5068     }
5069     return OK;
5070 }
5071 
5072 /*
5073  * Toplevel expression.
5074  * Sets "is_const" (if not NULL) to indicate the value is a constant.
5075  * Returns OK or FAIL.
5076  */
5077     static int
5078 compile_expr0_ext(char_u **arg,  cctx_T *cctx, int *is_const)
5079 {
5080     ppconst_T	ppconst;
5081 
5082     CLEAR_FIELD(ppconst);
5083     if (compile_expr1(arg, cctx, &ppconst) == FAIL)
5084     {
5085 	clear_ppconst(&ppconst);
5086 	return FAIL;
5087     }
5088     if (is_const != NULL)
5089 	*is_const = ppconst.pp_used > 0 || ppconst.pp_is_const;
5090     if (generate_ppconst(cctx, &ppconst) == FAIL)
5091 	return FAIL;
5092     return OK;
5093 }
5094 
5095 /*
5096  * Toplevel expression.
5097  */
5098     static int
5099 compile_expr0(char_u **arg,  cctx_T *cctx)
5100 {
5101     return compile_expr0_ext(arg, cctx, NULL);
5102 }
5103 
5104 /*
5105  * compile "return [expr]"
5106  */
5107     static char_u *
5108 compile_return(char_u *arg, int check_return_type, cctx_T *cctx)
5109 {
5110     char_u	*p = arg;
5111     garray_T	*stack = &cctx->ctx_type_stack;
5112     type_T	*stack_type;
5113 
5114     if (*p != NUL && *p != '|' && *p != '\n')
5115     {
5116 	// compile return argument into instructions
5117 	if (compile_expr0(&p, cctx) == FAIL)
5118 	    return NULL;
5119 
5120 	if (cctx->ctx_skip != SKIP_YES)
5121 	{
5122 	    stack_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
5123 	    if (check_return_type && (cctx->ctx_ufunc->uf_ret_type == NULL
5124 				|| cctx->ctx_ufunc->uf_ret_type == &t_unknown
5125 				|| cctx->ctx_ufunc->uf_ret_type == &t_any))
5126 	    {
5127 		cctx->ctx_ufunc->uf_ret_type = stack_type;
5128 	    }
5129 	    else
5130 	    {
5131 		if (cctx->ctx_ufunc->uf_ret_type->tt_type == VAR_VOID
5132 			&& stack_type->tt_type != VAR_VOID
5133 			&& stack_type->tt_type != VAR_UNKNOWN)
5134 		{
5135 		    emsg(_(e_returning_value_in_function_without_return_type));
5136 		    return NULL;
5137 		}
5138 		if (need_type(stack_type, cctx->ctx_ufunc->uf_ret_type, -1,
5139 						0, cctx, FALSE, FALSE) == FAIL)
5140 		    return NULL;
5141 	    }
5142 	}
5143     }
5144     else
5145     {
5146 	// "check_return_type" cannot be TRUE, only used for a lambda which
5147 	// always has an argument.
5148 	if (cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_VOID
5149 		&& cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_UNKNOWN)
5150 	{
5151 	    emsg(_(e_missing_return_value));
5152 	    return NULL;
5153 	}
5154 
5155 	// No argument, return zero.
5156 	generate_PUSHNR(cctx, 0);
5157     }
5158 
5159     // Undo any command modifiers.
5160     generate_undo_cmdmods(cctx);
5161 
5162     if (cctx->ctx_skip != SKIP_YES && generate_instr(cctx, ISN_RETURN) == NULL)
5163 	return NULL;
5164 
5165     // "return val | endif" is possible
5166     return skipwhite(p);
5167 }
5168 
5169 /*
5170  * Get a line from the compilation context, compatible with exarg_T getline().
5171  * Return a pointer to the line in allocated memory.
5172  * Return NULL for end-of-file or some error.
5173  */
5174     static char_u *
5175 exarg_getline(
5176 	int c UNUSED,
5177 	void *cookie,
5178 	int indent UNUSED,
5179 	getline_opt_T options UNUSED)
5180 {
5181     cctx_T  *cctx = (cctx_T *)cookie;
5182     char_u  *p;
5183 
5184     for (;;)
5185     {
5186 	if (cctx->ctx_lnum >= cctx->ctx_ufunc->uf_lines.ga_len - 1)
5187 	    return NULL;
5188 	++cctx->ctx_lnum;
5189 	p = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum];
5190 	// Comment lines result in NULL pointers, skip them.
5191 	if (p != NULL)
5192 	    return vim_strsave(p);
5193     }
5194 }
5195 
5196     void
5197 fill_exarg_from_cctx(exarg_T *eap, cctx_T *cctx)
5198 {
5199     eap->getline = exarg_getline;
5200     eap->cookie = cctx;
5201 }
5202 
5203 /*
5204  * Compile a nested :def command.
5205  */
5206     static char_u *
5207 compile_nested_function(exarg_T *eap, cctx_T *cctx)
5208 {
5209     int		is_global = *eap->arg == 'g' && eap->arg[1] == ':';
5210     char_u	*name_start = eap->arg;
5211     char_u	*name_end = to_name_end(eap->arg, TRUE);
5212     char_u	*lambda_name;
5213     ufunc_T	*ufunc;
5214     int		r = FAIL;
5215 
5216     if (eap->forceit)
5217     {
5218 	emsg(_(e_cannot_use_bang_with_nested_def));
5219 	return NULL;
5220     }
5221 
5222     if (*name_start == '/')
5223     {
5224 	name_end = skip_regexp(name_start + 1, '/', TRUE);
5225 	if (*name_end == '/')
5226 	    ++name_end;
5227 	eap->nextcmd = check_nextcmd(name_end);
5228     }
5229     if (name_end == name_start || *skipwhite(name_end) != '(')
5230     {
5231 	if (!ends_excmd2(name_start, name_end))
5232 	{
5233 	    semsg(_(e_invalid_command_str), eap->cmd);
5234 	    return NULL;
5235 	}
5236 
5237 	// "def" or "def Name": list functions
5238 	if (generate_DEF(cctx, name_start, name_end - name_start) == FAIL)
5239 	    return NULL;
5240 	return eap->nextcmd == NULL ? (char_u *)"" : eap->nextcmd;
5241     }
5242 
5243     // Only g:Func() can use a namespace.
5244     if (name_start[1] == ':' && !is_global)
5245     {
5246 	semsg(_(e_namespace_not_supported_str), name_start);
5247 	return NULL;
5248     }
5249     if (check_defined(name_start, name_end - name_start, cctx, FALSE) == FAIL)
5250 	return NULL;
5251 
5252     eap->arg = name_end;
5253     fill_exarg_from_cctx(eap, cctx);
5254 
5255     eap->forceit = FALSE;
5256     lambda_name = vim_strsave(get_lambda_name());
5257     if (lambda_name == NULL)
5258 	return NULL;
5259     ufunc = define_function(eap, lambda_name);
5260 
5261     if (ufunc == NULL)
5262     {
5263 	r = eap->skip ? OK : FAIL;
5264 	goto theend;
5265     }
5266 
5267     // copy over the block scope IDs before compiling
5268     if (!is_global && cctx->ctx_ufunc->uf_block_depth > 0)
5269     {
5270 	int block_depth = cctx->ctx_ufunc->uf_block_depth;
5271 
5272 	ufunc->uf_block_ids = ALLOC_MULT(int, block_depth);
5273 	if (ufunc->uf_block_ids != NULL)
5274 	{
5275 	    mch_memmove(ufunc->uf_block_ids, cctx->ctx_ufunc->uf_block_ids,
5276 						    sizeof(int) * block_depth);
5277 	    ufunc->uf_block_depth = block_depth;
5278 	}
5279     }
5280 
5281     if (func_needs_compiling(ufunc, PROFILING(ufunc))
5282 	    && compile_def_function(ufunc, TRUE, PROFILING(ufunc), cctx)
5283 								       == FAIL)
5284     {
5285 	func_ptr_unref(ufunc);
5286 	goto theend;
5287     }
5288 
5289     if (is_global)
5290     {
5291 	char_u *func_name = vim_strnsave(name_start + 2,
5292 						    name_end - name_start - 2);
5293 
5294 	if (func_name == NULL)
5295 	    r = FAIL;
5296 	else
5297 	{
5298 	    r = generate_NEWFUNC(cctx, lambda_name, func_name);
5299 	    lambda_name = NULL;
5300 	}
5301     }
5302     else
5303     {
5304 	// Define a local variable for the function reference.
5305 	lvar_T	*lvar = reserve_local(cctx, name_start, name_end - name_start,
5306 						    TRUE, ufunc->uf_func_type);
5307 
5308 	if (lvar == NULL)
5309 	    goto theend;
5310 	if (generate_FUNCREF(cctx, ufunc) == FAIL)
5311 	    goto theend;
5312 	r = generate_STORE(cctx, ISN_STORE, lvar->lv_idx, NULL);
5313     }
5314     // TODO: warning for trailing text?
5315 
5316 theend:
5317     vim_free(lambda_name);
5318     return r == FAIL ? NULL : (char_u *)"";
5319 }
5320 
5321 /*
5322  * Return the length of an assignment operator, or zero if there isn't one.
5323  */
5324     int
5325 assignment_len(char_u *p, int *heredoc)
5326 {
5327     if (*p == '=')
5328     {
5329 	if (p[1] == '<' && p[2] == '<')
5330 	{
5331 	    *heredoc = TRUE;
5332 	    return 3;
5333 	}
5334 	return 1;
5335     }
5336     if (vim_strchr((char_u *)"+-*/%", *p) != NULL && p[1] == '=')
5337 	return 2;
5338     if (STRNCMP(p, "..=", 3) == 0)
5339 	return 3;
5340     return 0;
5341 }
5342 
5343 // words that cannot be used as a variable
5344 static char *reserved[] = {
5345     "true",
5346     "false",
5347     "null",
5348     NULL
5349 };
5350 
5351 // Destination for an assignment or ":unlet" with an index.
5352 typedef enum {
5353     dest_local,
5354     dest_option,
5355     dest_env,
5356     dest_global,
5357     dest_buffer,
5358     dest_window,
5359     dest_tab,
5360     dest_vimvar,
5361     dest_script,
5362     dest_reg,
5363     dest_expr,
5364 } assign_dest_T;
5365 
5366 // Used by compile_lhs() to store information about the LHS of an assignment
5367 // and one argument of ":unlet" with an index.
5368 typedef struct {
5369     assign_dest_T   lhs_dest;	    // type of destination
5370 
5371     char_u	    *lhs_name;	    // allocated name including
5372 				    // "[expr]" or ".name".
5373     size_t	    lhs_varlen;	    // length of the variable without
5374 				    // "[expr]" or ".name"
5375     char_u	    *lhs_dest_end;  // end of the destination, including
5376 				    // "[expr]" or ".name".
5377 
5378     int		    lhs_has_index;  // has "[expr]" or ".name"
5379 
5380     int		    lhs_new_local;  // create new local variable
5381     int		    lhs_opt_flags;  // for when destination is an option
5382     int		    lhs_vimvaridx;  // for when destination is a v:var
5383 
5384     lvar_T	    lhs_local_lvar; // used for existing local destination
5385     lvar_T	    lhs_arg_lvar;   // used for argument destination
5386     lvar_T	    *lhs_lvar;	    // points to destination lvar
5387     int		    lhs_scriptvar_sid;
5388     int		    lhs_scriptvar_idx;
5389 
5390     int		    lhs_has_type;   // type was specified
5391     type_T	    *lhs_type;
5392     type_T	    *lhs_member_type;
5393 } lhs_T;
5394 
5395 /*
5396  * Generate the load instruction for "name".
5397  */
5398     static void
5399 generate_loadvar(
5400 	cctx_T		*cctx,
5401 	assign_dest_T	dest,
5402 	char_u		*name,
5403 	lvar_T		*lvar,
5404 	type_T		*type)
5405 {
5406     switch (dest)
5407     {
5408 	case dest_option:
5409 	    // TODO: check the option exists
5410 	    generate_LOAD(cctx, ISN_LOADOPT, 0, name, type);
5411 	    break;
5412 	case dest_global:
5413 	    if (vim_strchr(name, AUTOLOAD_CHAR) == NULL)
5414 		generate_LOAD(cctx, ISN_LOADG, 0, name + 2, type);
5415 	    else
5416 		generate_LOAD(cctx, ISN_LOADAUTO, 0, name, type);
5417 	    break;
5418 	case dest_buffer:
5419 	    generate_LOAD(cctx, ISN_LOADB, 0, name + 2, type);
5420 	    break;
5421 	case dest_window:
5422 	    generate_LOAD(cctx, ISN_LOADW, 0, name + 2, type);
5423 	    break;
5424 	case dest_tab:
5425 	    generate_LOAD(cctx, ISN_LOADT, 0, name + 2, type);
5426 	    break;
5427 	case dest_script:
5428 	    compile_load_scriptvar(cctx,
5429 		    name + (name[1] == ':' ? 2 : 0), NULL, NULL, TRUE);
5430 	    break;
5431 	case dest_env:
5432 	    // Include $ in the name here
5433 	    generate_LOAD(cctx, ISN_LOADENV, 0, name, type);
5434 	    break;
5435 	case dest_reg:
5436 	    generate_LOAD(cctx, ISN_LOADREG, name[1], NULL, &t_string);
5437 	    break;
5438 	case dest_vimvar:
5439 	    generate_LOADV(cctx, name + 2, TRUE);
5440 	    break;
5441 	case dest_local:
5442 	    if (lvar->lv_from_outer > 0)
5443 		generate_LOADOUTER(cctx, lvar->lv_idx, lvar->lv_from_outer,
5444 									 type);
5445 	    else
5446 		generate_LOAD(cctx, ISN_LOAD, lvar->lv_idx, NULL, type);
5447 	    break;
5448 	case dest_expr:
5449 	    // list or dict value should already be on the stack.
5450 	    break;
5451     }
5452 }
5453 
5454 /*
5455  * Skip over "[expr]" or ".member".
5456  * Does not check for any errors.
5457  */
5458     static char_u *
5459 skip_index(char_u *start)
5460 {
5461     char_u *p = start;
5462 
5463     if (*p == '[')
5464     {
5465 	p = skipwhite(p + 1);
5466 	(void)skip_expr(&p, NULL);
5467 	p = skipwhite(p);
5468 	if (*p == ']')
5469 	    return p + 1;
5470 	return p;
5471     }
5472     // if (*p == '.')
5473     return to_name_end(p + 1, TRUE);
5474 }
5475 
5476     void
5477 vim9_declare_error(char_u *name)
5478 {
5479     char *scope = "";
5480 
5481     switch (*name)
5482     {
5483 	case 'g': scope = _("global"); break;
5484 	case 'b': scope = _("buffer"); break;
5485 	case 'w': scope = _("window"); break;
5486 	case 't': scope = _("tab"); break;
5487 	case 'v': scope = "v:"; break;
5488 	case '$': semsg(_(e_cannot_declare_an_environment_variable), name);
5489 		  return;
5490 	case '&': semsg(_(e_cannot_declare_an_option), name);
5491 		  return;
5492 	case '@': semsg(_(e_cannot_declare_a_register_str), name);
5493 		  return;
5494 	default: return;
5495     }
5496     semsg(_(e_cannot_declare_a_scope_variable), scope, name);
5497 }
5498 
5499 /*
5500  * For one assignment figure out the type of destination.  Return it in "dest".
5501  * When not recognized "dest" is not set.
5502  * For an option "opt_flags" is set.
5503  * For a v:var "vimvaridx" is set.
5504  * "type" is set to the destination type if known, unchanted otherwise.
5505  * Return FAIL if an error message was given.
5506  */
5507     static int
5508 get_var_dest(
5509 	char_u		*name,
5510 	assign_dest_T	*dest,
5511 	int		cmdidx,
5512 	int		*opt_flags,
5513 	int		*vimvaridx,
5514 	type_T		**type,
5515 	cctx_T		*cctx)
5516 {
5517     char_u *p;
5518 
5519     if (*name == '&')
5520     {
5521 	int		cc;
5522 	long		numval;
5523 	getoption_T	opt_type;
5524 
5525 	*dest = dest_option;
5526 	if (cmdidx == CMD_final || cmdidx == CMD_const)
5527 	{
5528 	    emsg(_(e_const_option));
5529 	    return FAIL;
5530 	}
5531 	p = name;
5532 	p = find_option_end(&p, opt_flags);
5533 	if (p == NULL)
5534 	{
5535 	    // cannot happen?
5536 	    emsg(_(e_letunexp));
5537 	    return FAIL;
5538 	}
5539 	cc = *p;
5540 	*p = NUL;
5541 	opt_type = get_option_value(skip_option_env_lead(name),
5542 						    &numval, NULL, *opt_flags);
5543 	*p = cc;
5544 	switch (opt_type)
5545 	{
5546 	    case gov_unknown:
5547 		    semsg(_(e_unknown_option), name);
5548 		    return FAIL;
5549 	    case gov_string:
5550 	    case gov_hidden_string:
5551 		    *type = &t_string;
5552 		    break;
5553 	    case gov_bool:
5554 	    case gov_hidden_bool:
5555 		    *type = &t_bool;
5556 		    break;
5557 	    case gov_number:
5558 	    case gov_hidden_number:
5559 		    *type = &t_number;
5560 		    break;
5561 	}
5562     }
5563     else if (*name == '$')
5564     {
5565 	*dest = dest_env;
5566 	*type = &t_string;
5567     }
5568     else if (*name == '@')
5569     {
5570 	if (!valid_yank_reg(name[1], FALSE) || name[1] == '.')
5571 	{
5572 	    emsg_invreg(name[1]);
5573 	    return FAIL;
5574 	}
5575 	*dest = dest_reg;
5576 	*type = &t_string;
5577     }
5578     else if (STRNCMP(name, "g:", 2) == 0)
5579     {
5580 	*dest = dest_global;
5581     }
5582     else if (STRNCMP(name, "b:", 2) == 0)
5583     {
5584 	*dest = dest_buffer;
5585     }
5586     else if (STRNCMP(name, "w:", 2) == 0)
5587     {
5588 	*dest = dest_window;
5589     }
5590     else if (STRNCMP(name, "t:", 2) == 0)
5591     {
5592 	*dest = dest_tab;
5593     }
5594     else if (STRNCMP(name, "v:", 2) == 0)
5595     {
5596 	typval_T	*vtv;
5597 	int		di_flags;
5598 
5599 	*vimvaridx = find_vim_var(name + 2, &di_flags);
5600 	if (*vimvaridx < 0)
5601 	{
5602 	    semsg(_(e_variable_not_found_str), name);
5603 	    return FAIL;
5604 	}
5605 	// We use the current value of "sandbox" here, is that OK?
5606 	if (var_check_ro(di_flags, name, FALSE))
5607 	    return FAIL;
5608 	*dest = dest_vimvar;
5609 	vtv = get_vim_var_tv(*vimvaridx);
5610 	*type = typval2type_vimvar(vtv, cctx->ctx_type_list);
5611     }
5612     return OK;
5613 }
5614 
5615 /*
5616  * Generate a STORE instruction for "dest", not being "dest_local".
5617  * Return FAIL when out of memory.
5618  */
5619     static int
5620 generate_store_var(
5621 	cctx_T		*cctx,
5622 	assign_dest_T	dest,
5623 	int		opt_flags,
5624 	int		vimvaridx,
5625 	int		scriptvar_idx,
5626 	int		scriptvar_sid,
5627 	type_T		*type,
5628 	char_u		*name)
5629 {
5630     switch (dest)
5631     {
5632 	case dest_option:
5633 	    return generate_STOREOPT(cctx, skip_option_env_lead(name),
5634 								    opt_flags);
5635 	case dest_global:
5636 	    // include g: with the name, easier to execute that way
5637 	    return generate_STORE(cctx, vim_strchr(name, AUTOLOAD_CHAR) == NULL
5638 					? ISN_STOREG : ISN_STOREAUTO, 0, name);
5639 	case dest_buffer:
5640 	    // include b: with the name, easier to execute that way
5641 	    return generate_STORE(cctx, ISN_STOREB, 0, name);
5642 	case dest_window:
5643 	    // include w: with the name, easier to execute that way
5644 	    return generate_STORE(cctx, ISN_STOREW, 0, name);
5645 	case dest_tab:
5646 	    // include t: with the name, easier to execute that way
5647 	    return generate_STORE(cctx, ISN_STORET, 0, name);
5648 	case dest_env:
5649 	    return generate_STORE(cctx, ISN_STOREENV, 0, name + 1);
5650 	case dest_reg:
5651 	    return generate_STORE(cctx, ISN_STOREREG, name[1], NULL);
5652 	case dest_vimvar:
5653 	    return generate_STORE(cctx, ISN_STOREV, vimvaridx, NULL);
5654 	case dest_script:
5655 	    if (scriptvar_idx < 0)
5656 	    {
5657 		char_u  *name_s = name;
5658 		int	r;
5659 
5660 		// "s:" is included in the name.
5661 		r = generate_OLDSCRIPT(cctx, ISN_STORES, name_s,
5662 							  scriptvar_sid, type);
5663 		if (name_s != name)
5664 		    vim_free(name_s);
5665 		return r;
5666 	    }
5667 	    return generate_VIM9SCRIPT(cctx, ISN_STORESCRIPT,
5668 					   scriptvar_sid, scriptvar_idx, type);
5669 	case dest_local:
5670 	case dest_expr:
5671 	    // cannot happen
5672 	    break;
5673     }
5674     return FAIL;
5675 }
5676 
5677     static int
5678 is_decl_command(int cmdidx)
5679 {
5680     return cmdidx == CMD_let || cmdidx == CMD_var
5681 				 || cmdidx == CMD_final || cmdidx == CMD_const;
5682 }
5683 
5684 /*
5685  * Figure out the LHS type and other properties for an assignment or one item
5686  * of ":unlet" with an index.
5687  * Returns OK or FAIL.
5688  */
5689     static int
5690 compile_lhs(
5691 	char_u	*var_start,
5692 	lhs_T	*lhs,
5693 	int	cmdidx,
5694 	int	heredoc,
5695 	int	oplen,
5696 	cctx_T	*cctx)
5697 {
5698     char_u	*var_end;
5699     int		is_decl = is_decl_command(cmdidx);
5700 
5701     CLEAR_POINTER(lhs);
5702     lhs->lhs_dest = dest_local;
5703     lhs->lhs_vimvaridx = -1;
5704     lhs->lhs_scriptvar_idx = -1;
5705 
5706     // "dest_end" is the end of the destination, including "[expr]" or
5707     // ".name".
5708     // "var_end" is the end of the variable/option/etc. name.
5709     lhs->lhs_dest_end = skip_var_one(var_start, FALSE);
5710     if (*var_start == '@')
5711 	var_end = var_start + 2;
5712     else
5713     {
5714 	// skip over the leading "&", "&l:", "&g:" and "$"
5715 	var_end = skip_option_env_lead(var_start);
5716 	var_end = to_name_end(var_end, TRUE);
5717     }
5718 
5719     // "a: type" is declaring variable "a" with a type, not dict "a:".
5720     if (is_decl && lhs->lhs_dest_end == var_start + 2
5721 					       && lhs->lhs_dest_end[-1] == ':')
5722 	--lhs->lhs_dest_end;
5723     if (is_decl && var_end == var_start + 2 && var_end[-1] == ':')
5724 	--var_end;
5725 
5726     // compute the length of the destination without "[expr]" or ".name"
5727     lhs->lhs_varlen = var_end - var_start;
5728     lhs->lhs_name = vim_strnsave(var_start, lhs->lhs_varlen);
5729     if (lhs->lhs_name == NULL)
5730 	return FAIL;
5731 
5732     if (lhs->lhs_dest_end > var_start + lhs->lhs_varlen)
5733 	// Something follows after the variable: "var[idx]" or "var.key".
5734 	lhs->lhs_has_index = TRUE;
5735 
5736     if (heredoc)
5737 	lhs->lhs_type = &t_list_string;
5738     else
5739 	lhs->lhs_type = &t_any;
5740 
5741     if (cctx->ctx_skip != SKIP_YES)
5742     {
5743 	int	    declare_error = FALSE;
5744 
5745 	if (get_var_dest(lhs->lhs_name, &lhs->lhs_dest, cmdidx,
5746 				      &lhs->lhs_opt_flags, &lhs->lhs_vimvaridx,
5747 						 &lhs->lhs_type, cctx) == FAIL)
5748 	    return FAIL;
5749 	if (lhs->lhs_dest != dest_local)
5750 	{
5751 	    // Specific kind of variable recognized.
5752 	    declare_error = is_decl;
5753 	}
5754 	else
5755 	{
5756 	    int	    idx;
5757 
5758 	    // No specific kind of variable recognized, just a name.
5759 	    for (idx = 0; reserved[idx] != NULL; ++idx)
5760 		if (STRCMP(reserved[idx], lhs->lhs_name) == 0)
5761 		{
5762 		    semsg(_(e_cannot_use_reserved_name), lhs->lhs_name);
5763 		    return FAIL;
5764 		}
5765 
5766 
5767 	    if (lookup_local(var_start, lhs->lhs_varlen,
5768 					     &lhs->lhs_local_lvar, cctx) == OK)
5769 		lhs->lhs_lvar = &lhs->lhs_local_lvar;
5770 	    else
5771 	    {
5772 		CLEAR_FIELD(lhs->lhs_arg_lvar);
5773 		if (arg_exists(var_start, lhs->lhs_varlen,
5774 			 &lhs->lhs_arg_lvar.lv_idx, &lhs->lhs_arg_lvar.lv_type,
5775 			    &lhs->lhs_arg_lvar.lv_from_outer, cctx) == OK)
5776 		{
5777 		    if (is_decl)
5778 		    {
5779 			semsg(_(e_str_is_used_as_argument), lhs->lhs_name);
5780 			return FAIL;
5781 		    }
5782 		    lhs->lhs_lvar = &lhs->lhs_arg_lvar;
5783 		}
5784 	    }
5785 	    if (lhs->lhs_lvar != NULL)
5786 	    {
5787 		if (is_decl)
5788 		{
5789 		    semsg(_(e_variable_already_declared), lhs->lhs_name);
5790 		    return FAIL;
5791 		}
5792 	    }
5793 	    else
5794 	    {
5795 		int script_namespace = lhs->lhs_varlen > 1
5796 				       && STRNCMP(var_start, "s:", 2) == 0;
5797 		int script_var = (script_namespace
5798 			? script_var_exists(var_start + 2, lhs->lhs_varlen - 2,
5799 							       FALSE, cctx)
5800 			  : script_var_exists(var_start, lhs->lhs_varlen,
5801 							    TRUE, cctx)) == OK;
5802 		imported_T  *import =
5803 			       find_imported(var_start, lhs->lhs_varlen, cctx);
5804 
5805 		if (script_namespace || script_var || import != NULL)
5806 		{
5807 		    char_u	*rawname = lhs->lhs_name
5808 					   + (lhs->lhs_name[1] == ':' ? 2 : 0);
5809 
5810 		    if (is_decl)
5811 		    {
5812 			if (script_namespace)
5813 			    semsg(_(e_cannot_declare_script_variable_in_function),
5814 								lhs->lhs_name);
5815 			else
5816 			    semsg(_(e_variable_already_declared_in_script_str),
5817 								lhs->lhs_name);
5818 			return FAIL;
5819 		    }
5820 		    else if (cctx->ctx_ufunc->uf_script_ctx_version
5821 							 == SCRIPT_VERSION_VIM9
5822 				    && script_namespace
5823 				    && !script_var && import == NULL)
5824 		    {
5825 			semsg(_(e_unknown_variable_str), lhs->lhs_name);
5826 			return FAIL;
5827 		    }
5828 
5829 		    lhs->lhs_dest = dest_script;
5830 
5831 		    // existing script-local variables should have a type
5832 		    lhs->lhs_scriptvar_sid = current_sctx.sc_sid;
5833 		    if (import != NULL)
5834 			lhs->lhs_scriptvar_sid = import->imp_sid;
5835 		    if (SCRIPT_ID_VALID(lhs->lhs_scriptvar_sid))
5836 		    {
5837 			// Check writable only when no index follows.
5838 			lhs->lhs_scriptvar_idx = get_script_item_idx(
5839 					       lhs->lhs_scriptvar_sid, rawname,
5840 			      lhs->lhs_has_index ? ASSIGN_FINAL : ASSIGN_CONST,
5841 									 cctx);
5842 			if (lhs->lhs_scriptvar_idx >= 0)
5843 			{
5844 			    scriptitem_T *si = SCRIPT_ITEM(
5845 						       lhs->lhs_scriptvar_sid);
5846 			    svar_T	 *sv =
5847 					    ((svar_T *)si->sn_var_vals.ga_data)
5848 						      + lhs->lhs_scriptvar_idx;
5849 			    lhs->lhs_type = sv->sv_type;
5850 			}
5851 		    }
5852 		}
5853 		else if (check_defined(var_start, lhs->lhs_varlen, cctx, FALSE)
5854 								       == FAIL)
5855 		    return FAIL;
5856 	    }
5857 	}
5858 
5859 	if (declare_error)
5860 	{
5861 	    vim9_declare_error(lhs->lhs_name);
5862 	    return FAIL;
5863 	}
5864     }
5865 
5866     // handle "a:name" as a name, not index "name" on "a"
5867     if (lhs->lhs_varlen > 1 || var_start[lhs->lhs_varlen] != ':')
5868 	var_end = lhs->lhs_dest_end;
5869 
5870     if (lhs->lhs_dest != dest_option)
5871     {
5872 	if (is_decl && *var_end == ':')
5873 	{
5874 	    char_u *p;
5875 
5876 	    // parse optional type: "let var: type = expr"
5877 	    if (!VIM_ISWHITE(var_end[1]))
5878 	    {
5879 		semsg(_(e_white_space_required_after_str_str), ":", var_end);
5880 		return FAIL;
5881 	    }
5882 	    p = skipwhite(var_end + 1);
5883 	    lhs->lhs_type = parse_type(&p, cctx->ctx_type_list, TRUE);
5884 	    if (lhs->lhs_type == NULL)
5885 		return FAIL;
5886 	    lhs->lhs_has_type = TRUE;
5887 	}
5888 	else if (lhs->lhs_lvar != NULL)
5889 	    lhs->lhs_type = lhs->lhs_lvar->lv_type;
5890     }
5891 
5892     if (oplen == 3 && !heredoc && lhs->lhs_dest != dest_global
5893 		    && lhs->lhs_type->tt_type != VAR_STRING
5894 		    && lhs->lhs_type->tt_type != VAR_ANY)
5895     {
5896 	emsg(_(e_can_only_concatenate_to_string));
5897 	return FAIL;
5898     }
5899 
5900     if (lhs->lhs_lvar == NULL && lhs->lhs_dest == dest_local
5901 						 && cctx->ctx_skip != SKIP_YES)
5902     {
5903 	if (oplen > 1 && !heredoc)
5904 	{
5905 	    // +=, /=, etc. require an existing variable
5906 	    semsg(_(e_cannot_use_operator_on_new_variable), lhs->lhs_name);
5907 	    return FAIL;
5908 	}
5909 	if (!is_decl)
5910 	{
5911 	    semsg(_(e_unknown_variable_str), lhs->lhs_name);
5912 	    return FAIL;
5913 	}
5914 
5915 	// Check the name is valid for a funcref.
5916 	if ((lhs->lhs_type->tt_type == VAR_FUNC
5917 				      || lhs->lhs_type->tt_type == VAR_PARTIAL)
5918 		&& var_wrong_func_name(lhs->lhs_name, TRUE))
5919 	    return FAIL;
5920 
5921 	// New local variable.
5922 	lhs->lhs_lvar = reserve_local(cctx, var_start, lhs->lhs_varlen,
5923 		    cmdidx == CMD_final || cmdidx == CMD_const, lhs->lhs_type);
5924 	if (lhs->lhs_lvar == NULL)
5925 	    return FAIL;
5926 	lhs->lhs_new_local = TRUE;
5927     }
5928 
5929     lhs->lhs_member_type = lhs->lhs_type;
5930     if (lhs->lhs_has_index)
5931     {
5932 	// Something follows after the variable: "var[idx]" or "var.key".
5933 	// TODO: should we also handle "->func()" here?
5934 	if (is_decl)
5935 	{
5936 	    emsg(_(e_cannot_use_index_when_declaring_variable));
5937 	    return FAIL;
5938 	}
5939 
5940 	if (var_start[lhs->lhs_varlen] == '['
5941 					  || var_start[lhs->lhs_varlen] == '.')
5942 	{
5943 	    char_u	*after = var_start + lhs->lhs_varlen;
5944 	    char_u	*p;
5945 
5946 	    // Only the last index is used below, if there are others
5947 	    // before it generate code for the expression.  Thus for
5948 	    // "ll[1][2]" the expression is "ll[1]" and "[2]" is the index.
5949 	    for (;;)
5950 	    {
5951 		p = skip_index(after);
5952 		if (*p != '[' && *p != '.')
5953 		    break;
5954 		after = p;
5955 	    }
5956 	    if (after > var_start + lhs->lhs_varlen)
5957 	    {
5958 		lhs->lhs_varlen = after - var_start;
5959 		lhs->lhs_dest = dest_expr;
5960 		// We don't know the type before evaluating the expression,
5961 		// use "any" until then.
5962 		lhs->lhs_type = &t_any;
5963 	    }
5964 
5965 	    if (lhs->lhs_type->tt_member == NULL)
5966 		lhs->lhs_member_type = &t_any;
5967 	    else
5968 		lhs->lhs_member_type = lhs->lhs_type->tt_member;
5969 	}
5970 	else
5971 	{
5972 	    semsg("Not supported yet: %s", var_start);
5973 	    return FAIL;
5974 	}
5975     }
5976     return OK;
5977 }
5978 
5979 /*
5980  * Assignment to a list or dict member, or ":unlet" for the item, using the
5981  * information in "lhs".
5982  * Returns OK or FAIL.
5983  */
5984     static int
5985 compile_assign_unlet(
5986 	char_u	*var_start,
5987 	lhs_T	*lhs,
5988 	int	is_assign,
5989 	type_T	*rhs_type,
5990 	cctx_T	*cctx)
5991 {
5992     char_u	*p;
5993     int		r;
5994     vartype_T	dest_type;
5995     size_t	varlen = lhs->lhs_varlen;
5996     garray_T    *stack = &cctx->ctx_type_stack;
5997     int		range = FALSE;
5998 
5999     // Compile the "idx" in "var[idx]" or "key" in "var.key".
6000     p = var_start + varlen;
6001     if (*p == '[')
6002     {
6003 	p = skipwhite(p + 1);
6004 	r = compile_expr0(&p, cctx);
6005 
6006 	if (r == OK && *skipwhite(p) == ':')
6007 	{
6008 	    // unlet var[idx : idx]
6009 	    if (is_assign)
6010 	    {
6011 		semsg(_(e_cannot_use_range_with_assignment_str), p);
6012 		return FAIL;
6013 	    }
6014 	    range = TRUE;
6015 	    p = skipwhite(p);
6016 	    if (!IS_WHITE_OR_NUL(p[-1]) || !IS_WHITE_OR_NUL(p[1]))
6017 	    {
6018 		semsg(_(e_white_space_required_before_and_after_str_at_str),
6019 								      ":", p);
6020 		return FAIL;
6021 	    }
6022 	    p = skipwhite(p + 1);
6023 	    r = compile_expr0(&p, cctx);
6024 	}
6025 
6026 	if (r == OK && *skipwhite(p) != ']')
6027 	{
6028 	    // this should not happen
6029 	    emsg(_(e_missbrac));
6030 	    r = FAIL;
6031 	}
6032     }
6033     else // if (*p == '.')
6034     {
6035 	char_u *key_end = to_name_end(p + 1, TRUE);
6036 	char_u *key = vim_strnsave(p + 1, key_end - p - 1);
6037 
6038 	r = generate_PUSHS(cctx, key);
6039     }
6040     if (r == FAIL)
6041 	return FAIL;
6042 
6043     if (lhs->lhs_type == &t_any)
6044     {
6045 	// Index on variable of unknown type: check at runtime.
6046 	dest_type = VAR_ANY;
6047     }
6048     else
6049     {
6050 	dest_type = lhs->lhs_type->tt_type;
6051 	if (dest_type == VAR_DICT && range)
6052 	{
6053 	    emsg(e_cannot_use_range_with_dictionary);
6054 	    return FAIL;
6055 	}
6056 	if (dest_type == VAR_DICT && may_generate_2STRING(-1, cctx) == FAIL)
6057 	    return FAIL;
6058 	if (dest_type == VAR_LIST)
6059 	{
6060 	    if (range
6061 		  && need_type(((type_T **)stack->ga_data)[stack->ga_len - 2],
6062 				 &t_number, -1, 0, cctx, FALSE, FALSE) == FAIL)
6063 		return FAIL;
6064 	    if (need_type(((type_T **)stack->ga_data)[stack->ga_len - 1],
6065 				 &t_number, -1, 0, cctx, FALSE, FALSE) == FAIL)
6066 		return FAIL;
6067 	}
6068     }
6069 
6070     // Load the dict or list.  On the stack we then have:
6071     // - value (for assignment, not for :unlet)
6072     // - index
6073     // - for [a : b] second index
6074     // - variable
6075     if (lhs->lhs_dest == dest_expr)
6076     {
6077 	int	    c = var_start[varlen];
6078 
6079 	// Evaluate "ll[expr]" of "ll[expr][idx]"
6080 	p = var_start;
6081 	var_start[varlen] = NUL;
6082 	if (compile_expr0(&p, cctx) == OK && p != var_start + varlen)
6083 	{
6084 	    // this should not happen
6085 	    emsg(_(e_missbrac));
6086 	    return FAIL;
6087 	}
6088 	var_start[varlen] = c;
6089 
6090 	lhs->lhs_type = stack->ga_len == 0 ? &t_void
6091 		  : ((type_T **)stack->ga_data)[stack->ga_len - 1];
6092 	// now we can properly check the type
6093 	if (lhs->lhs_type->tt_member != NULL && rhs_type != &t_void
6094 		&& need_type(rhs_type, lhs->lhs_type->tt_member, -2, 0, cctx,
6095 							 FALSE, FALSE) == FAIL)
6096 	    return FAIL;
6097     }
6098     else
6099 	generate_loadvar(cctx, lhs->lhs_dest, lhs->lhs_name,
6100 						 lhs->lhs_lvar, lhs->lhs_type);
6101 
6102     if (dest_type == VAR_LIST || dest_type == VAR_DICT || dest_type == VAR_ANY)
6103     {
6104 	if (is_assign)
6105 	{
6106 	    isn_T	*isn = generate_instr_drop(cctx, ISN_STOREINDEX, 3);
6107 
6108 	    if (isn == NULL)
6109 		return FAIL;
6110 	    isn->isn_arg.vartype = dest_type;
6111 	}
6112 	else if (range)
6113 	{
6114 	    if (generate_instr_drop(cctx, ISN_UNLETRANGE, 3) == NULL)
6115 		return FAIL;
6116 	}
6117 	else
6118 	{
6119 	    if (generate_instr_drop(cctx, ISN_UNLETINDEX, 2) == NULL)
6120 		return FAIL;
6121 	}
6122     }
6123     else
6124     {
6125 	emsg(_(e_indexable_type_required));
6126 	return FAIL;
6127     }
6128 
6129     return OK;
6130 }
6131 
6132 /*
6133  * Compile declaration and assignment:
6134  * "let name"
6135  * "var name = expr"
6136  * "final name = expr"
6137  * "const name = expr"
6138  * "name = expr"
6139  * "arg" points to "name".
6140  * Return NULL for an error.
6141  * Return "arg" if it does not look like a variable list.
6142  */
6143     static char_u *
6144 compile_assignment(char_u *arg, exarg_T *eap, cmdidx_T cmdidx, cctx_T *cctx)
6145 {
6146     char_u	*var_start;
6147     char_u	*p;
6148     char_u	*end = arg;
6149     char_u	*ret = NULL;
6150     int		var_count = 0;
6151     int		var_idx;
6152     int		semicolon = 0;
6153     garray_T	*instr = &cctx->ctx_instr;
6154     garray_T    *stack = &cctx->ctx_type_stack;
6155     char_u	*op;
6156     int		oplen = 0;
6157     int		heredoc = FALSE;
6158     type_T	*rhs_type = &t_any;
6159     char_u	*sp;
6160     int		is_decl = is_decl_command(cmdidx);
6161     lhs_T	lhs;
6162 
6163     // Skip over the "var" or "[var, var]" to get to any "=".
6164     p = skip_var_list(arg, TRUE, &var_count, &semicolon, TRUE);
6165     if (p == NULL)
6166 	return *arg == '[' ? arg : NULL;
6167 
6168     if (var_count > 0 && is_decl)
6169     {
6170 	// TODO: should we allow this, and figure out type inference from list
6171 	// members?
6172 	emsg(_(e_cannot_use_list_for_declaration));
6173 	return NULL;
6174     }
6175     lhs.lhs_name = NULL;
6176 
6177     sp = p;
6178     p = skipwhite(p);
6179     op = p;
6180     oplen = assignment_len(p, &heredoc);
6181 
6182     if (var_count > 0 && oplen == 0)
6183 	// can be something like "[1, 2]->func()"
6184 	return arg;
6185 
6186     if (oplen > 0 && (!VIM_ISWHITE(*sp) || !IS_WHITE_OR_NUL(op[oplen])))
6187     {
6188 	error_white_both(op, oplen);
6189 	return NULL;
6190     }
6191 
6192     if (heredoc)
6193     {
6194 	list_T	   *l;
6195 	listitem_T *li;
6196 
6197 	// [let] varname =<< [trim] {end}
6198 	eap->getline = exarg_getline;
6199 	eap->cookie = cctx;
6200 	l = heredoc_get(eap, op + 3, FALSE);
6201 	if (l == NULL)
6202 	    return NULL;
6203 
6204 	if (cctx->ctx_skip != SKIP_YES)
6205 	{
6206 	    // Push each line and the create the list.
6207 	    FOR_ALL_LIST_ITEMS(l, li)
6208 	    {
6209 		generate_PUSHS(cctx, li->li_tv.vval.v_string);
6210 		li->li_tv.vval.v_string = NULL;
6211 	    }
6212 	    generate_NEWLIST(cctx, l->lv_len);
6213 	}
6214 	list_free(l);
6215 	p += STRLEN(p);
6216 	end = p;
6217     }
6218     else if (var_count > 0)
6219     {
6220 	char_u *wp;
6221 
6222 	// for "[var, var] = expr" evaluate the expression here, loop over the
6223 	// list of variables below.
6224 	// A line break may follow the "=".
6225 
6226 	wp = op + oplen;
6227 	if (may_get_next_line_error(wp, &p, cctx) == FAIL)
6228 	    return FAIL;
6229 	if (compile_expr0(&p, cctx) == FAIL)
6230 	    return NULL;
6231 	end = p;
6232 
6233 	if (cctx->ctx_skip != SKIP_YES)
6234 	{
6235 	    type_T	*stacktype;
6236 
6237 	    stacktype = stack->ga_len == 0 ? &t_void
6238 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
6239 	    if (stacktype->tt_type == VAR_VOID)
6240 	    {
6241 		emsg(_(e_cannot_use_void_value));
6242 		goto theend;
6243 	    }
6244 	    if (need_type(stacktype, &t_list_any, -1, 0, cctx,
6245 							 FALSE, FALSE) == FAIL)
6246 		goto theend;
6247 	    // TODO: check the length of a constant list here
6248 	    generate_CHECKLEN(cctx, semicolon ? var_count - 1 : var_count,
6249 								    semicolon);
6250 	    if (stacktype->tt_member != NULL)
6251 		rhs_type = stacktype->tt_member;
6252 	}
6253     }
6254 
6255     /*
6256      * Loop over variables in "[var, var] = expr".
6257      * For "var = expr" and "let var: type" this is done only once.
6258      */
6259     if (var_count > 0)
6260 	var_start = skipwhite(arg + 1);  // skip over the "["
6261     else
6262 	var_start = arg;
6263     for (var_idx = 0; var_idx == 0 || var_idx < var_count; var_idx++)
6264     {
6265 	int		instr_count = -1;
6266 
6267 	vim_free(lhs.lhs_name);
6268 
6269 	/*
6270 	 * Figure out the LHS type and other properties.
6271 	 */
6272 	if (compile_lhs(var_start, &lhs, cmdidx, heredoc, oplen, cctx) == FAIL)
6273 	    goto theend;
6274 
6275 	if (!lhs.lhs_has_index && lhs.lhs_lvar == &lhs.lhs_arg_lvar)
6276 	{
6277 	    semsg(_(e_cannot_assign_to_argument), lhs.lhs_name);
6278 	    goto theend;
6279 	}
6280 	if (!is_decl && lhs.lhs_lvar != NULL
6281 			       && lhs.lhs_lvar->lv_const && !lhs.lhs_has_index)
6282 	{
6283 	    semsg(_(e_cannot_assign_to_constant), lhs.lhs_name);
6284 	    goto theend;
6285 	}
6286 
6287 	if (!heredoc)
6288 	{
6289 	    if (cctx->ctx_skip == SKIP_YES)
6290 	    {
6291 		if (oplen > 0 && var_count == 0)
6292 		{
6293 		    // skip over the "=" and the expression
6294 		    p = skipwhite(op + oplen);
6295 		    compile_expr0(&p, cctx);
6296 		}
6297 	    }
6298 	    else if (oplen > 0)
6299 	    {
6300 		int	is_const = FALSE;
6301 		char_u	*wp;
6302 
6303 		// For "var = expr" evaluate the expression.
6304 		if (var_count == 0)
6305 		{
6306 		    int	r;
6307 
6308 		    // for "+=", "*=", "..=" etc. first load the current value
6309 		    if (*op != '=')
6310 		    {
6311 			generate_loadvar(cctx, lhs.lhs_dest, lhs.lhs_name,
6312 						   lhs.lhs_lvar, lhs.lhs_type);
6313 
6314 			if (lhs.lhs_has_index)
6315 			{
6316 			    // TODO: get member from list or dict
6317 			    emsg("Index with operation not supported yet");
6318 			    goto theend;
6319 			}
6320 		    }
6321 
6322 		    // Compile the expression.  Temporarily hide the new local
6323 		    // variable here, it is not available to this expression.
6324 		    if (lhs.lhs_new_local)
6325 			--cctx->ctx_locals.ga_len;
6326 		    instr_count = instr->ga_len;
6327 		    wp = op + oplen;
6328 		    if (may_get_next_line_error(wp, &p, cctx) == FAIL)
6329 		    {
6330 			if (lhs.lhs_new_local)
6331 			    ++cctx->ctx_locals.ga_len;
6332 			goto theend;
6333 		    }
6334 		    r = compile_expr0_ext(&p, cctx, &is_const);
6335 		    if (lhs.lhs_new_local)
6336 			++cctx->ctx_locals.ga_len;
6337 		    if (r == FAIL)
6338 			goto theend;
6339 		}
6340 		else if (semicolon && var_idx == var_count - 1)
6341 		{
6342 		    // For "[var; var] = expr" get the rest of the list
6343 		    if (generate_SLICE(cctx, var_count - 1) == FAIL)
6344 			goto theend;
6345 		}
6346 		else
6347 		{
6348 		    // For "[var, var] = expr" get the "var_idx" item from the
6349 		    // list.
6350 		    if (generate_GETITEM(cctx, var_idx) == FAIL)
6351 			goto theend;
6352 		}
6353 
6354 		rhs_type = stack->ga_len == 0 ? &t_void
6355 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
6356 		if (lhs.lhs_lvar != NULL && (is_decl || !lhs.lhs_has_type))
6357 		{
6358 		    if ((rhs_type->tt_type == VAR_FUNC
6359 				|| rhs_type->tt_type == VAR_PARTIAL)
6360 			    && !lhs.lhs_has_index
6361 			    && var_wrong_func_name(lhs.lhs_name, TRUE))
6362 			goto theend;
6363 
6364 		    if (lhs.lhs_new_local && !lhs.lhs_has_type)
6365 		    {
6366 			if (rhs_type->tt_type == VAR_VOID)
6367 			{
6368 			    emsg(_(e_cannot_use_void_value));
6369 			    goto theend;
6370 			}
6371 			else
6372 			{
6373 			    // An empty list or dict has a &t_unknown member,
6374 			    // for a variable that implies &t_any.
6375 			    if (rhs_type == &t_list_empty)
6376 				lhs.lhs_lvar->lv_type = &t_list_any;
6377 			    else if (rhs_type == &t_dict_empty)
6378 				lhs.lhs_lvar->lv_type = &t_dict_any;
6379 			    else if (rhs_type == &t_unknown)
6380 				lhs.lhs_lvar->lv_type = &t_any;
6381 			    else
6382 				lhs.lhs_lvar->lv_type = rhs_type;
6383 			}
6384 		    }
6385 		    else if (*op == '=')
6386 		    {
6387 			type_T *use_type = lhs.lhs_lvar->lv_type;
6388 
6389 			// without operator check type here, otherwise below
6390 			if (lhs.lhs_has_index)
6391 			    use_type = lhs.lhs_member_type;
6392 			if (need_type(rhs_type, use_type, -1, 0, cctx,
6393 						      FALSE, is_const) == FAIL)
6394 			    goto theend;
6395 		    }
6396 		}
6397 		else if (*p != '=' && need_type(rhs_type, lhs.lhs_member_type,
6398 					    -1, 0, cctx, FALSE, FALSE) == FAIL)
6399 		    goto theend;
6400 	    }
6401 	    else if (cmdidx == CMD_final)
6402 	    {
6403 		emsg(_(e_final_requires_a_value));
6404 		goto theend;
6405 	    }
6406 	    else if (cmdidx == CMD_const)
6407 	    {
6408 		emsg(_(e_const_requires_a_value));
6409 		goto theend;
6410 	    }
6411 	    else if (!lhs.lhs_has_type || lhs.lhs_dest == dest_option)
6412 	    {
6413 		emsg(_(e_type_or_initialization_required));
6414 		goto theend;
6415 	    }
6416 	    else
6417 	    {
6418 		// variables are always initialized
6419 		if (ga_grow(instr, 1) == FAIL)
6420 		    goto theend;
6421 		switch (lhs.lhs_member_type->tt_type)
6422 		{
6423 		    case VAR_BOOL:
6424 			generate_PUSHBOOL(cctx, VVAL_FALSE);
6425 			break;
6426 		    case VAR_FLOAT:
6427 #ifdef FEAT_FLOAT
6428 			generate_PUSHF(cctx, 0.0);
6429 #endif
6430 			break;
6431 		    case VAR_STRING:
6432 			generate_PUSHS(cctx, NULL);
6433 			break;
6434 		    case VAR_BLOB:
6435 			generate_PUSHBLOB(cctx, blob_alloc());
6436 			break;
6437 		    case VAR_FUNC:
6438 			generate_PUSHFUNC(cctx, NULL, &t_func_void);
6439 			break;
6440 		    case VAR_LIST:
6441 			generate_NEWLIST(cctx, 0);
6442 			break;
6443 		    case VAR_DICT:
6444 			generate_NEWDICT(cctx, 0);
6445 			break;
6446 		    case VAR_JOB:
6447 			generate_PUSHJOB(cctx, NULL);
6448 			break;
6449 		    case VAR_CHANNEL:
6450 			generate_PUSHCHANNEL(cctx, NULL);
6451 			break;
6452 		    case VAR_NUMBER:
6453 		    case VAR_UNKNOWN:
6454 		    case VAR_ANY:
6455 		    case VAR_PARTIAL:
6456 		    case VAR_VOID:
6457 		    case VAR_SPECIAL:  // cannot happen
6458 			generate_PUSHNR(cctx, 0);
6459 			break;
6460 		}
6461 	    }
6462 	    if (var_count == 0)
6463 		end = p;
6464 	}
6465 
6466 	// no need to parse more when skipping
6467 	if (cctx->ctx_skip == SKIP_YES)
6468 	    break;
6469 
6470 	if (oplen > 0 && *op != '=')
6471 	{
6472 	    type_T	    *expected;
6473 	    type_T	    *stacktype;
6474 
6475 	    if (*op == '.')
6476 		expected = &t_string;
6477 	    else
6478 		expected = lhs.lhs_member_type;
6479 	    stacktype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
6480 	    if (
6481 #ifdef FEAT_FLOAT
6482 		// If variable is float operation with number is OK.
6483 		!(expected == &t_float && stacktype == &t_number) &&
6484 #endif
6485 		    need_type(stacktype, expected, -1, 0, cctx,
6486 							 FALSE, FALSE) == FAIL)
6487 		goto theend;
6488 
6489 	    if (*op == '.')
6490 	    {
6491 		if (generate_instr_drop(cctx, ISN_CONCAT, 1) == NULL)
6492 		    goto theend;
6493 	    }
6494 	    else if (*op == '+')
6495 	    {
6496 		if (generate_add_instr(cctx,
6497 			    operator_type(lhs.lhs_member_type, stacktype),
6498 				       lhs.lhs_member_type, stacktype) == FAIL)
6499 		    goto theend;
6500 	    }
6501 	    else if (generate_two_op(cctx, op) == FAIL)
6502 		goto theend;
6503 	}
6504 
6505 	if (lhs.lhs_has_index)
6506 	{
6507 	    // Use the info in "lhs" to store the value at the index in the
6508 	    // list or dict.
6509 	    if (compile_assign_unlet(var_start, &lhs, TRUE, rhs_type, cctx)
6510 								       == FAIL)
6511 		goto theend;
6512 	}
6513 	else
6514 	{
6515 	    if (is_decl && cmdidx == CMD_const && (lhs.lhs_dest == dest_script
6516 						|| lhs.lhs_dest == dest_local))
6517 		// ":const var": lock the value, but not referenced variables
6518 		generate_LOCKCONST(cctx);
6519 
6520 	    if (is_decl
6521 		    && (lhs.lhs_type->tt_type == VAR_DICT
6522 					  || lhs.lhs_type->tt_type == VAR_LIST)
6523 		    && lhs.lhs_type->tt_member != NULL
6524 		    && lhs.lhs_type->tt_member != &t_any
6525 		    && lhs.lhs_type->tt_member != &t_unknown)
6526 		// Set the type in the list or dict, so that it can be checked,
6527 		// also in legacy script.
6528 		generate_SETTYPE(cctx, lhs.lhs_type);
6529 
6530 	    if (lhs.lhs_dest != dest_local)
6531 	    {
6532 		if (generate_store_var(cctx, lhs.lhs_dest,
6533 			    lhs.lhs_opt_flags, lhs.lhs_vimvaridx,
6534 			    lhs.lhs_scriptvar_idx, lhs.lhs_scriptvar_sid,
6535 					   lhs.lhs_type, lhs.lhs_name) == FAIL)
6536 		    goto theend;
6537 	    }
6538 	    else if (lhs.lhs_lvar != NULL)
6539 	    {
6540 		isn_T *isn = ((isn_T *)instr->ga_data)
6541 						   + instr->ga_len - 1;
6542 
6543 		// optimization: turn "var = 123" from ISN_PUSHNR +
6544 		// ISN_STORE into ISN_STORENR
6545 		if (lhs.lhs_lvar->lv_from_outer == 0
6546 				&& instr->ga_len == instr_count + 1
6547 				&& isn->isn_type == ISN_PUSHNR)
6548 		{
6549 		    varnumber_T val = isn->isn_arg.number;
6550 
6551 		    isn->isn_type = ISN_STORENR;
6552 		    isn->isn_arg.storenr.stnr_idx = lhs.lhs_lvar->lv_idx;
6553 		    isn->isn_arg.storenr.stnr_val = val;
6554 		    if (stack->ga_len > 0)
6555 			--stack->ga_len;
6556 		}
6557 		else if (lhs.lhs_lvar->lv_from_outer > 0)
6558 		    generate_STOREOUTER(cctx, lhs.lhs_lvar->lv_idx,
6559 						  lhs.lhs_lvar->lv_from_outer);
6560 		else
6561 		    generate_STORE(cctx, ISN_STORE, lhs.lhs_lvar->lv_idx, NULL);
6562 	    }
6563 	}
6564 
6565 	if (var_idx + 1 < var_count)
6566 	    var_start = skipwhite(lhs.lhs_dest_end + 1);
6567     }
6568 
6569     // for "[var, var] = expr" drop the "expr" value
6570     if (var_count > 0 && !semicolon)
6571     {
6572 	if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
6573 	    goto theend;
6574     }
6575 
6576     ret = skipwhite(end);
6577 
6578 theend:
6579     vim_free(lhs.lhs_name);
6580     return ret;
6581 }
6582 
6583 /*
6584  * Check for an assignment at "eap->cmd", compile it if found.
6585  * Return NOTDONE if there is none, FAIL for failure, OK if done.
6586  */
6587     static int
6588 may_compile_assignment(exarg_T *eap, char_u **line, cctx_T *cctx)
6589 {
6590     char_u  *pskip;
6591     char_u  *p;
6592 
6593     // Assuming the command starts with a variable or function name,
6594     // find what follows.
6595     // Skip over "var.member", "var[idx]" and the like.
6596     // Also "&opt = val", "$ENV = val" and "@r = val".
6597     pskip = (*eap->cmd == '&' || *eap->cmd == '$' || *eap->cmd == '@')
6598 						 ? eap->cmd + 1 : eap->cmd;
6599     p = to_name_end(pskip, TRUE);
6600     if (p > eap->cmd && *p != NUL)
6601     {
6602 	char_u *var_end;
6603 	int	oplen;
6604 	int	heredoc;
6605 
6606 	if (eap->cmd[0] == '@')
6607 	    var_end = eap->cmd + 2;
6608 	else
6609 	    var_end = find_name_end(pskip, NULL, NULL,
6610 					FNE_CHECK_START | FNE_INCL_BR);
6611 	oplen = assignment_len(skipwhite(var_end), &heredoc);
6612 	if (oplen > 0)
6613 	{
6614 	    size_t len = p - eap->cmd;
6615 
6616 	    // Recognize an assignment if we recognize the variable
6617 	    // name:
6618 	    // "g:var = expr"
6619 	    // "local = expr"  where "local" is a local var.
6620 	    // "script = expr"  where "script" is a script-local var.
6621 	    // "import = expr"  where "import" is an imported var
6622 	    // "&opt = expr"
6623 	    // "$ENV = expr"
6624 	    // "@r = expr"
6625 	    if (*eap->cmd == '&'
6626 		    || *eap->cmd == '$'
6627 		    || *eap->cmd == '@'
6628 		    || ((len) > 2 && eap->cmd[1] == ':')
6629 		    || variable_exists(eap->cmd, len, cctx))
6630 	    {
6631 		*line = compile_assignment(eap->cmd, eap, CMD_SIZE, cctx);
6632 		if (*line == NULL || *line == eap->cmd)
6633 		    return FAIL;
6634 		return OK;
6635 	    }
6636 	}
6637     }
6638 
6639     if (*eap->cmd == '[')
6640     {
6641 	// [var, var] = expr
6642 	*line = compile_assignment(eap->cmd, eap, CMD_SIZE, cctx);
6643 	if (*line == NULL)
6644 	    return FAIL;
6645 	if (*line != eap->cmd)
6646 	    return OK;
6647     }
6648     return NOTDONE;
6649 }
6650 
6651 /*
6652  * Check if "name" can be "unlet".
6653  */
6654     int
6655 check_vim9_unlet(char_u *name)
6656 {
6657     if (name[1] != ':' || vim_strchr((char_u *)"gwtb", *name) == NULL)
6658     {
6659 	// "unlet s:var" is allowed in legacy script.
6660 	if (*name == 's' && !script_is_vim9())
6661 	    return OK;
6662 	semsg(_(e_cannot_unlet_str), name);
6663 	return FAIL;
6664     }
6665     return OK;
6666 }
6667 
6668 /*
6669  * Callback passed to ex_unletlock().
6670  */
6671     static int
6672 compile_unlet(
6673     lval_T  *lvp,
6674     char_u  *name_end,
6675     exarg_T *eap,
6676     int	    deep UNUSED,
6677     void    *coookie)
6678 {
6679     cctx_T	*cctx = coookie;
6680     char_u	*p = lvp->ll_name;
6681     int		cc = *name_end;
6682     int		ret = OK;
6683 
6684     if (cctx->ctx_skip == SKIP_YES)
6685 	return OK;
6686 
6687     *name_end = NUL;
6688     if (*p == '$')
6689     {
6690 	// :unlet $ENV_VAR
6691 	ret = generate_UNLET(cctx, ISN_UNLETENV, p + 1, eap->forceit);
6692     }
6693     else if (vim_strchr(p, '.') != NULL || vim_strchr(p, '[') != NULL)
6694     {
6695 	lhs_T	    lhs;
6696 
6697 	// This is similar to assigning: lookup the list/dict, compile the
6698 	// idx/key.  Then instead of storing the value unlet the item.
6699 	// unlet {list}[idx]
6700 	// unlet {dict}[key]  dict.key
6701 	//
6702 	// Figure out the LHS type and other properties.
6703 	//
6704 	ret = compile_lhs(p, &lhs, CMD_unlet, FALSE, 0, cctx);
6705 
6706 	// : unlet an indexed item
6707 	if (!lhs.lhs_has_index)
6708 	{
6709 	    iemsg("called compile_lhs() without an index");
6710 	    ret = FAIL;
6711 	}
6712 	else
6713 	{
6714 	    // Use the info in "lhs" to unlet the item at the index in the
6715 	    // list or dict.
6716 	    ret = compile_assign_unlet(p, &lhs, FALSE, &t_void, cctx);
6717 	}
6718 
6719 	vim_free(lhs.lhs_name);
6720     }
6721     else if (check_vim9_unlet(p) == FAIL)
6722     {
6723 	ret = FAIL;
6724     }
6725     else
6726     {
6727 	// Normal name.  Only supports g:, w:, t: and b: namespaces.
6728 	ret = generate_UNLET(cctx, ISN_UNLET, p, eap->forceit);
6729     }
6730 
6731     *name_end = cc;
6732     return ret;
6733 }
6734 
6735 /*
6736  * Callback passed to ex_unletlock().
6737  */
6738     static int
6739 compile_lock_unlock(
6740     lval_T  *lvp,
6741     char_u  *name_end,
6742     exarg_T *eap,
6743     int	    deep UNUSED,
6744     void    *coookie)
6745 {
6746     cctx_T	*cctx = coookie;
6747     int		cc = *name_end;
6748     char_u	*p = lvp->ll_name;
6749     int		ret = OK;
6750     size_t	len;
6751     char_u	*buf;
6752 
6753     if (cctx->ctx_skip == SKIP_YES)
6754 	return OK;
6755 
6756     // Cannot use :lockvar and :unlockvar on local variables.
6757     if (p[1] != ':')
6758     {
6759 	char_u *end = skip_var_one(p, FALSE);
6760 
6761 	if (lookup_local(p, end - p, NULL, cctx) == OK)
6762 	{
6763 	    emsg(_(e_cannot_lock_unlock_local_variable));
6764 	    return FAIL;
6765 	}
6766     }
6767 
6768     // Checking is done at runtime.
6769     *name_end = NUL;
6770     len = name_end - p + 20;
6771     buf = alloc(len);
6772     if (buf == NULL)
6773 	ret = FAIL;
6774     else
6775     {
6776 	vim_snprintf((char *)buf, len, "%s %s",
6777 		eap->cmdidx == CMD_lockvar ? "lockvar" : "unlockvar",
6778 		p);
6779 	ret = generate_EXEC(cctx, buf);
6780 
6781 	vim_free(buf);
6782 	*name_end = cc;
6783     }
6784     return ret;
6785 }
6786 
6787 /*
6788  * compile "unlet var", "lock var" and "unlock var"
6789  * "arg" points to "var".
6790  */
6791     static char_u *
6792 compile_unletlock(char_u *arg, exarg_T *eap, cctx_T *cctx)
6793 {
6794     ex_unletlock(eap, arg, 0, GLV_NO_AUTOLOAD | GLV_COMPILING,
6795 	    eap->cmdidx == CMD_unlet ? compile_unlet : compile_lock_unlock,
6796 	    cctx);
6797     return eap->nextcmd == NULL ? (char_u *)"" : eap->nextcmd;
6798 }
6799 
6800 /*
6801  * Compile an :import command.
6802  */
6803     static char_u *
6804 compile_import(char_u *arg, cctx_T *cctx)
6805 {
6806     return handle_import(arg, &cctx->ctx_imports, 0, NULL, cctx);
6807 }
6808 
6809 /*
6810  * generate a jump to the ":endif"/":endfor"/":endwhile"/":finally"/":endtry".
6811  */
6812     static int
6813 compile_jump_to_end(endlabel_T **el, jumpwhen_T when, cctx_T *cctx)
6814 {
6815     garray_T	*instr = &cctx->ctx_instr;
6816     endlabel_T  *endlabel = ALLOC_CLEAR_ONE(endlabel_T);
6817 
6818     if (endlabel == NULL)
6819 	return FAIL;
6820     endlabel->el_next = *el;
6821     *el = endlabel;
6822     endlabel->el_end_label = instr->ga_len;
6823 
6824     generate_JUMP(cctx, when, 0);
6825     return OK;
6826 }
6827 
6828     static void
6829 compile_fill_jump_to_end(endlabel_T **el, int jump_where, cctx_T *cctx)
6830 {
6831     garray_T	*instr = &cctx->ctx_instr;
6832 
6833     while (*el != NULL)
6834     {
6835 	endlabel_T  *cur = (*el);
6836 	isn_T	    *isn;
6837 
6838 	isn = ((isn_T *)instr->ga_data) + cur->el_end_label;
6839 	isn->isn_arg.jump.jump_where = jump_where;
6840 	*el = cur->el_next;
6841 	vim_free(cur);
6842     }
6843 }
6844 
6845     static void
6846 compile_free_jump_to_end(endlabel_T **el)
6847 {
6848     while (*el != NULL)
6849     {
6850 	endlabel_T  *cur = (*el);
6851 
6852 	*el = cur->el_next;
6853 	vim_free(cur);
6854     }
6855 }
6856 
6857 /*
6858  * Create a new scope and set up the generic items.
6859  */
6860     static scope_T *
6861 new_scope(cctx_T *cctx, scopetype_T type)
6862 {
6863     scope_T *scope = ALLOC_CLEAR_ONE(scope_T);
6864 
6865     if (scope == NULL)
6866 	return NULL;
6867     scope->se_outer = cctx->ctx_scope;
6868     cctx->ctx_scope = scope;
6869     scope->se_type = type;
6870     scope->se_local_count = cctx->ctx_locals.ga_len;
6871     return scope;
6872 }
6873 
6874 /*
6875  * Free the current scope and go back to the outer scope.
6876  */
6877     static void
6878 drop_scope(cctx_T *cctx)
6879 {
6880     scope_T *scope = cctx->ctx_scope;
6881 
6882     if (scope == NULL)
6883     {
6884 	iemsg("calling drop_scope() without a scope");
6885 	return;
6886     }
6887     cctx->ctx_scope = scope->se_outer;
6888     switch (scope->se_type)
6889     {
6890 	case IF_SCOPE:
6891 	    compile_free_jump_to_end(&scope->se_u.se_if.is_end_label); break;
6892 	case FOR_SCOPE:
6893 	    compile_free_jump_to_end(&scope->se_u.se_for.fs_end_label); break;
6894 	case WHILE_SCOPE:
6895 	    compile_free_jump_to_end(&scope->se_u.se_while.ws_end_label); break;
6896 	case TRY_SCOPE:
6897 	    compile_free_jump_to_end(&scope->se_u.se_try.ts_end_label); break;
6898 	case NO_SCOPE:
6899 	case BLOCK_SCOPE:
6900 	    break;
6901     }
6902     vim_free(scope);
6903 }
6904 
6905 /*
6906  * compile "if expr"
6907  *
6908  * "if expr" Produces instructions:
6909  *	EVAL expr		Push result of "expr"
6910  *	JUMP_IF_FALSE end
6911  *	... body ...
6912  * end:
6913  *
6914  * "if expr | else" Produces instructions:
6915  *	EVAL expr		Push result of "expr"
6916  *	JUMP_IF_FALSE else
6917  *	... body ...
6918  *	JUMP_ALWAYS end
6919  * else:
6920  *	... body ...
6921  * end:
6922  *
6923  * "if expr1 | elseif expr2 | else" Produces instructions:
6924  *	EVAL expr		Push result of "expr"
6925  *	JUMP_IF_FALSE elseif
6926  *	... body ...
6927  *	JUMP_ALWAYS end
6928  * elseif:
6929  *	EVAL expr		Push result of "expr"
6930  *	JUMP_IF_FALSE else
6931  *	... body ...
6932  *	JUMP_ALWAYS end
6933  * else:
6934  *	... body ...
6935  * end:
6936  */
6937     static char_u *
6938 compile_if(char_u *arg, cctx_T *cctx)
6939 {
6940     char_u	*p = arg;
6941     garray_T	*instr = &cctx->ctx_instr;
6942     int		instr_count = instr->ga_len;
6943     scope_T	*scope;
6944     skip_T	skip_save = cctx->ctx_skip;
6945     ppconst_T	ppconst;
6946 
6947     CLEAR_FIELD(ppconst);
6948     if (compile_expr1(&p, cctx, &ppconst) == FAIL)
6949     {
6950 	clear_ppconst(&ppconst);
6951 	return NULL;
6952     }
6953     if (!ends_excmd2(arg, skipwhite(p)))
6954     {
6955 	semsg(_(e_trailing_arg), p);
6956 	return NULL;
6957     }
6958     if (cctx->ctx_skip == SKIP_YES)
6959 	clear_ppconst(&ppconst);
6960     else if (instr->ga_len == instr_count && ppconst.pp_used == 1)
6961     {
6962 	int error = FALSE;
6963 	int v;
6964 
6965 	// The expression results in a constant.
6966 	v = tv_get_bool_chk(&ppconst.pp_tv[0], &error);
6967 	clear_ppconst(&ppconst);
6968 	if (error)
6969 	    return NULL;
6970 	cctx->ctx_skip = v ? SKIP_NOT : SKIP_YES;
6971     }
6972     else
6973     {
6974 	// Not a constant, generate instructions for the expression.
6975 	cctx->ctx_skip = SKIP_UNKNOWN;
6976 	if (generate_ppconst(cctx, &ppconst) == FAIL)
6977 	    return NULL;
6978 	if (bool_on_stack(cctx) == FAIL)
6979 	    return NULL;
6980     }
6981 
6982     // CMDMOD_REV must come before the jump
6983     generate_undo_cmdmods(cctx);
6984 
6985     scope = new_scope(cctx, IF_SCOPE);
6986     if (scope == NULL)
6987 	return NULL;
6988     scope->se_skip_save = skip_save;
6989     // "is_had_return" will be reset if any block does not end in :return
6990     scope->se_u.se_if.is_had_return = TRUE;
6991 
6992     if (cctx->ctx_skip == SKIP_UNKNOWN)
6993     {
6994 	// "where" is set when ":elseif", "else" or ":endif" is found
6995 	scope->se_u.se_if.is_if_label = instr->ga_len;
6996 	generate_JUMP(cctx, JUMP_IF_FALSE, 0);
6997     }
6998     else
6999 	scope->se_u.se_if.is_if_label = -1;
7000 
7001 #ifdef FEAT_PROFILE
7002     if (cctx->ctx_profiling && cctx->ctx_skip == SKIP_YES
7003 						      && skip_save != SKIP_YES)
7004     {
7005 	// generated a profile start, need to generate a profile end, since it
7006 	// won't be done after returning
7007 	cctx->ctx_skip = SKIP_NOT;
7008 	generate_instr(cctx, ISN_PROF_END);
7009 	cctx->ctx_skip = SKIP_YES;
7010     }
7011 #endif
7012 
7013     return p;
7014 }
7015 
7016     static char_u *
7017 compile_elseif(char_u *arg, cctx_T *cctx)
7018 {
7019     char_u	*p = arg;
7020     garray_T	*instr = &cctx->ctx_instr;
7021     int		instr_count = instr->ga_len;
7022     isn_T	*isn;
7023     scope_T	*scope = cctx->ctx_scope;
7024     ppconst_T	ppconst;
7025     skip_T	save_skip = cctx->ctx_skip;
7026 
7027     if (scope == NULL || scope->se_type != IF_SCOPE)
7028     {
7029 	emsg(_(e_elseif_without_if));
7030 	return NULL;
7031     }
7032     unwind_locals(cctx, scope->se_local_count);
7033     if (!cctx->ctx_had_return)
7034 	scope->se_u.se_if.is_had_return = FALSE;
7035 
7036     if (cctx->ctx_skip == SKIP_NOT)
7037     {
7038 	// previous block was executed, this one and following will not
7039 	cctx->ctx_skip = SKIP_YES;
7040 	scope->se_u.se_if.is_seen_skip_not = TRUE;
7041     }
7042     if (scope->se_u.se_if.is_seen_skip_not)
7043     {
7044 	// A previous block was executed, skip over expression and bail out.
7045 	// Do not count the "elseif" for profiling and cmdmod
7046 	instr->ga_len = current_instr_idx(cctx);
7047 
7048 	skip_expr_cctx(&p, cctx);
7049 	return p;
7050     }
7051 
7052     if (cctx->ctx_skip == SKIP_UNKNOWN)
7053     {
7054 	int moved_cmdmod = FALSE;
7055 
7056 	// Move any CMDMOD instruction to after the jump
7057 	if (((isn_T *)instr->ga_data)[instr->ga_len - 1].isn_type == ISN_CMDMOD)
7058 	{
7059 	    if (ga_grow(instr, 1) == FAIL)
7060 		return NULL;
7061 	    ((isn_T *)instr->ga_data)[instr->ga_len] =
7062 				  ((isn_T *)instr->ga_data)[instr->ga_len - 1];
7063 	    --instr->ga_len;
7064 	    moved_cmdmod = TRUE;
7065 	}
7066 
7067 	if (compile_jump_to_end(&scope->se_u.se_if.is_end_label,
7068 						    JUMP_ALWAYS, cctx) == FAIL)
7069 	    return NULL;
7070 	// previous "if" or "elseif" jumps here
7071 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
7072 	isn->isn_arg.jump.jump_where = instr->ga_len;
7073 	if (moved_cmdmod)
7074 	    ++instr->ga_len;
7075     }
7076 
7077     // compile "expr"; if we know it evaluates to FALSE skip the block
7078     CLEAR_FIELD(ppconst);
7079     if (cctx->ctx_skip == SKIP_YES)
7080     {
7081 	cctx->ctx_skip = SKIP_UNKNOWN;
7082 #ifdef FEAT_PROFILE
7083 	if (cctx->ctx_profiling)
7084 	{
7085 	    // the previous block was skipped, need to profile this line
7086 	    generate_instr(cctx, ISN_PROF_START);
7087 	    instr_count = instr->ga_len;
7088 	}
7089 #endif
7090     }
7091     if (compile_expr1(&p, cctx, &ppconst) == FAIL)
7092     {
7093 	clear_ppconst(&ppconst);
7094 	return NULL;
7095     }
7096     cctx->ctx_skip = save_skip;
7097     if (!ends_excmd2(arg, skipwhite(p)))
7098     {
7099 	semsg(_(e_trailing_arg), p);
7100 	return NULL;
7101     }
7102     if (scope->se_skip_save == SKIP_YES)
7103 	clear_ppconst(&ppconst);
7104     else if (instr->ga_len == instr_count && ppconst.pp_used == 1)
7105     {
7106 	int error = FALSE;
7107 	int v;
7108 
7109 	// The expression results in a constant.
7110 	// TODO: how about nesting?
7111 	v = tv_get_bool_chk(&ppconst.pp_tv[0], &error);
7112 	if (error)
7113 	    return NULL;
7114 	cctx->ctx_skip = v ? SKIP_NOT : SKIP_YES;
7115 	clear_ppconst(&ppconst);
7116 	scope->se_u.se_if.is_if_label = -1;
7117     }
7118     else
7119     {
7120 	// Not a constant, generate instructions for the expression.
7121 	cctx->ctx_skip = SKIP_UNKNOWN;
7122 	if (generate_ppconst(cctx, &ppconst) == FAIL)
7123 	    return NULL;
7124 	if (bool_on_stack(cctx) == FAIL)
7125 	    return NULL;
7126 
7127 	// CMDMOD_REV must come before the jump
7128 	generate_undo_cmdmods(cctx);
7129 
7130 	// "where" is set when ":elseif", "else" or ":endif" is found
7131 	scope->se_u.se_if.is_if_label = instr->ga_len;
7132 	generate_JUMP(cctx, JUMP_IF_FALSE, 0);
7133     }
7134 
7135     return p;
7136 }
7137 
7138     static char_u *
7139 compile_else(char_u *arg, cctx_T *cctx)
7140 {
7141     char_u	*p = arg;
7142     garray_T	*instr = &cctx->ctx_instr;
7143     isn_T	*isn;
7144     scope_T	*scope = cctx->ctx_scope;
7145 
7146     if (scope == NULL || scope->se_type != IF_SCOPE)
7147     {
7148 	emsg(_(e_else_without_if));
7149 	return NULL;
7150     }
7151     unwind_locals(cctx, scope->se_local_count);
7152     if (!cctx->ctx_had_return)
7153 	scope->se_u.se_if.is_had_return = FALSE;
7154     scope->se_u.se_if.is_seen_else = TRUE;
7155 
7156 #ifdef FEAT_PROFILE
7157     if (cctx->ctx_profiling)
7158     {
7159 	if (cctx->ctx_skip == SKIP_NOT
7160 		&& ((isn_T *)instr->ga_data)[instr->ga_len - 1]
7161 						   .isn_type == ISN_PROF_START)
7162 	    // the previous block was executed, do not count "else" for profiling
7163 	    --instr->ga_len;
7164 	if (cctx->ctx_skip == SKIP_YES && !scope->se_u.se_if.is_seen_skip_not)
7165 	{
7166 	    // the previous block was not executed, this one will, do count the
7167 	    // "else" for profiling
7168 	    cctx->ctx_skip = SKIP_NOT;
7169 	    generate_instr(cctx, ISN_PROF_END);
7170 	    generate_instr(cctx, ISN_PROF_START);
7171 	    cctx->ctx_skip = SKIP_YES;
7172 	}
7173     }
7174 #endif
7175 
7176     if (!scope->se_u.se_if.is_seen_skip_not && scope->se_skip_save != SKIP_YES)
7177     {
7178 	// jump from previous block to the end, unless the else block is empty
7179 	if (cctx->ctx_skip == SKIP_UNKNOWN)
7180 	{
7181 	    if (!cctx->ctx_had_return
7182 		    && compile_jump_to_end(&scope->se_u.se_if.is_end_label,
7183 						    JUMP_ALWAYS, cctx) == FAIL)
7184 		return NULL;
7185 	}
7186 
7187 	if (cctx->ctx_skip == SKIP_UNKNOWN)
7188 	{
7189 	    if (scope->se_u.se_if.is_if_label >= 0)
7190 	    {
7191 		// previous "if" or "elseif" jumps here
7192 		isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
7193 		isn->isn_arg.jump.jump_where = instr->ga_len;
7194 		scope->se_u.se_if.is_if_label = -1;
7195 	    }
7196 	}
7197 
7198 	if (cctx->ctx_skip != SKIP_UNKNOWN)
7199 	    cctx->ctx_skip = cctx->ctx_skip == SKIP_YES ? SKIP_NOT : SKIP_YES;
7200     }
7201 
7202     return p;
7203 }
7204 
7205     static char_u *
7206 compile_endif(char_u *arg, cctx_T *cctx)
7207 {
7208     scope_T	*scope = cctx->ctx_scope;
7209     ifscope_T	*ifscope;
7210     garray_T	*instr = &cctx->ctx_instr;
7211     isn_T	*isn;
7212 
7213     if (misplaced_cmdmod(cctx))
7214 	return NULL;
7215 
7216     if (scope == NULL || scope->se_type != IF_SCOPE)
7217     {
7218 	emsg(_(e_endif_without_if));
7219 	return NULL;
7220     }
7221     ifscope = &scope->se_u.se_if;
7222     unwind_locals(cctx, scope->se_local_count);
7223     if (!cctx->ctx_had_return)
7224 	ifscope->is_had_return = FALSE;
7225 
7226     if (scope->se_u.se_if.is_if_label >= 0)
7227     {
7228 	// previous "if" or "elseif" jumps here
7229 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
7230 	isn->isn_arg.jump.jump_where = instr->ga_len;
7231     }
7232     // Fill in the "end" label in jumps at the end of the blocks.
7233     compile_fill_jump_to_end(&ifscope->is_end_label, instr->ga_len, cctx);
7234 
7235 #ifdef FEAT_PROFILE
7236     // even when skipping we count the endif as executed, unless the block it's
7237     // in is skipped
7238     if (cctx->ctx_profiling && cctx->ctx_skip == SKIP_YES
7239 					    && scope->se_skip_save != SKIP_YES)
7240     {
7241 	cctx->ctx_skip = SKIP_NOT;
7242 	generate_instr(cctx, ISN_PROF_START);
7243     }
7244 #endif
7245     cctx->ctx_skip = scope->se_skip_save;
7246 
7247     // If all the blocks end in :return and there is an :else then the
7248     // had_return flag is set.
7249     cctx->ctx_had_return = ifscope->is_had_return && ifscope->is_seen_else;
7250 
7251     drop_scope(cctx);
7252     return arg;
7253 }
7254 
7255 /*
7256  * Compile "for var in expr":
7257  *
7258  * Produces instructions:
7259  *       PUSHNR -1
7260  *       STORE loop-idx		Set index to -1
7261  *       EVAL expr		result of "expr" on top of stack
7262  * top:  FOR loop-idx, end	Increment index, use list on bottom of stack
7263  *				- if beyond end, jump to "end"
7264  *				- otherwise get item from list and push it
7265  *       STORE var		Store item in "var"
7266  *       ... body ...
7267  *       JUMP top		Jump back to repeat
7268  * end:	 DROP			Drop the result of "expr"
7269  *
7270  * Compile "for [var1, var2] in expr" - as above, but instead of "STORE var":
7271  *	 UNPACK 2		Split item in 2
7272  *       STORE var1		Store item in "var1"
7273  *       STORE var2		Store item in "var2"
7274  */
7275     static char_u *
7276 compile_for(char_u *arg_start, cctx_T *cctx)
7277 {
7278     char_u	*arg;
7279     char_u	*arg_end;
7280     char_u	*name = NULL;
7281     char_u	*p;
7282     char_u	*wp;
7283     int		var_count = 0;
7284     int		semicolon = FALSE;
7285     size_t	varlen;
7286     garray_T	*stack = &cctx->ctx_type_stack;
7287     scope_T	*scope;
7288     lvar_T	*loop_lvar;	// loop iteration variable
7289     lvar_T	*var_lvar;	// variable for "var"
7290     type_T	*vartype;
7291     type_T	*item_type = &t_any;
7292     int		idx;
7293 
7294     p = skip_var_list(arg_start, TRUE, &var_count, &semicolon, FALSE);
7295     if (p == NULL)
7296 	return NULL;
7297     if (var_count == 0)
7298 	var_count = 1;
7299 
7300     // consume "in"
7301     wp = p;
7302     if (may_get_next_line_error(wp, &p, cctx) == FAIL)
7303 	return NULL;
7304     if (STRNCMP(p, "in", 2) != 0 || !IS_WHITE_OR_NUL(p[2]))
7305     {
7306 	emsg(_(e_missing_in));
7307 	return NULL;
7308     }
7309     wp = p + 2;
7310     if (may_get_next_line_error(wp, &p, cctx) == FAIL)
7311 	return NULL;
7312 
7313     scope = new_scope(cctx, FOR_SCOPE);
7314     if (scope == NULL)
7315 	return NULL;
7316 
7317     // Reserve a variable to store the loop iteration counter and initialize it
7318     // to -1.
7319     loop_lvar = reserve_local(cctx, (char_u *)"", 0, FALSE, &t_number);
7320     if (loop_lvar == NULL)
7321     {
7322 	// out of memory
7323 	drop_scope(cctx);
7324 	return NULL;
7325     }
7326     generate_STORENR(cctx, loop_lvar->lv_idx, -1);
7327 
7328     // compile "expr", it remains on the stack until "endfor"
7329     arg = p;
7330     if (compile_expr0(&arg, cctx) == FAIL)
7331     {
7332 	drop_scope(cctx);
7333 	return NULL;
7334     }
7335     arg_end = arg;
7336 
7337     // If we know the type of "var" and it is a not a list or string we can
7338     // give an error now.
7339     vartype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
7340     if (vartype->tt_type != VAR_LIST && vartype->tt_type != VAR_STRING
7341 						&& vartype->tt_type != VAR_ANY)
7342     {
7343 	// TODO: support Blob
7344 	semsg(_(e_for_loop_on_str_not_supported),
7345 					       vartype_name(vartype->tt_type));
7346 	drop_scope(cctx);
7347 	return NULL;
7348     }
7349 
7350     if (vartype->tt_type == VAR_LIST && vartype->tt_member->tt_type != VAR_ANY)
7351     {
7352 	if (var_count == 1)
7353 	    item_type = vartype->tt_member;
7354 	else if (vartype->tt_member->tt_type == VAR_LIST
7355 		      && vartype->tt_member->tt_member->tt_type != VAR_ANY)
7356 	    item_type = vartype->tt_member->tt_member;
7357     }
7358 
7359     // CMDMOD_REV must come before the FOR instruction
7360     generate_undo_cmdmods(cctx);
7361 
7362     // "for_end" is set when ":endfor" is found
7363     scope->se_u.se_for.fs_top_label = current_instr_idx(cctx);
7364     generate_FOR(cctx, loop_lvar->lv_idx);
7365 
7366     arg = arg_start;
7367     if (var_count > 1)
7368     {
7369 	generate_UNPACK(cctx, var_count, semicolon);
7370 	arg = skipwhite(arg + 1);	// skip white after '['
7371 
7372 	// the list item is replaced by a number of items
7373 	if (ga_grow(stack, var_count - 1) == FAIL)
7374 	{
7375 	    drop_scope(cctx);
7376 	    return NULL;
7377 	}
7378 	--stack->ga_len;
7379 	for (idx = 0; idx < var_count; ++idx)
7380 	{
7381 	    ((type_T **)stack->ga_data)[stack->ga_len] =
7382 				(semicolon && idx == 0) ? vartype : item_type;
7383 	    ++stack->ga_len;
7384 	}
7385     }
7386 
7387     for (idx = 0; idx < var_count; ++idx)
7388     {
7389 	assign_dest_T	dest = dest_local;
7390 	int		opt_flags = 0;
7391 	int		vimvaridx = -1;
7392 	type_T		*type = &t_any;
7393 
7394 	p = skip_var_one(arg, FALSE);
7395 	varlen = p - arg;
7396 	name = vim_strnsave(arg, varlen);
7397 	if (name == NULL)
7398 	    goto failed;
7399 
7400 	// TODO: script var not supported?
7401 	if (get_var_dest(name, &dest, CMD_for, &opt_flags,
7402 					      &vimvaridx, &type, cctx) == FAIL)
7403 	    goto failed;
7404 	if (dest != dest_local)
7405 	{
7406 	    if (generate_store_var(cctx, dest, opt_flags, vimvaridx,
7407 						     0, 0, type, name) == FAIL)
7408 		goto failed;
7409 	}
7410 	else
7411 	{
7412 	    if (lookup_local(arg, varlen, NULL, cctx) == OK)
7413 	    {
7414 		semsg(_(e_variable_already_declared), arg);
7415 		goto failed;
7416 	    }
7417 
7418 	    if (STRNCMP(name, "s:", 2) == 0)
7419 	    {
7420 		semsg(_(e_cannot_declare_script_variable_in_function), name);
7421 		goto failed;
7422 	    }
7423 
7424 	    // Reserve a variable to store "var".
7425 	    // TODO: check for type
7426 	    var_lvar = reserve_local(cctx, arg, varlen, FALSE, &t_any);
7427 	    if (var_lvar == NULL)
7428 		// out of memory or used as an argument
7429 		goto failed;
7430 
7431 	    if (semicolon && idx == var_count - 1)
7432 		var_lvar->lv_type = vartype;
7433 	    else
7434 		var_lvar->lv_type = item_type;
7435 	    generate_STORE(cctx, ISN_STORE, var_lvar->lv_idx, NULL);
7436 	}
7437 
7438 	if (*p == ':')
7439 	    p = skip_type(skipwhite(p + 1), FALSE);
7440 	if (*p == ',' || *p == ';')
7441 	    ++p;
7442 	arg = skipwhite(p);
7443 	vim_free(name);
7444     }
7445 
7446     return arg_end;
7447 
7448 failed:
7449     vim_free(name);
7450     drop_scope(cctx);
7451     return NULL;
7452 }
7453 
7454 /*
7455  * compile "endfor"
7456  */
7457     static char_u *
7458 compile_endfor(char_u *arg, cctx_T *cctx)
7459 {
7460     garray_T	*instr = &cctx->ctx_instr;
7461     scope_T	*scope = cctx->ctx_scope;
7462     forscope_T	*forscope;
7463     isn_T	*isn;
7464 
7465     if (misplaced_cmdmod(cctx))
7466 	return NULL;
7467 
7468     if (scope == NULL || scope->se_type != FOR_SCOPE)
7469     {
7470 	emsg(_(e_for));
7471 	return NULL;
7472     }
7473     forscope = &scope->se_u.se_for;
7474     cctx->ctx_scope = scope->se_outer;
7475     unwind_locals(cctx, scope->se_local_count);
7476 
7477     // At end of ":for" scope jump back to the FOR instruction.
7478     generate_JUMP(cctx, JUMP_ALWAYS, forscope->fs_top_label);
7479 
7480     // Fill in the "end" label in the FOR statement so it can jump here
7481     isn = ((isn_T *)instr->ga_data) + forscope->fs_top_label;
7482     isn->isn_arg.forloop.for_end = instr->ga_len;
7483 
7484     // Fill in the "end" label any BREAK statements
7485     compile_fill_jump_to_end(&forscope->fs_end_label, instr->ga_len, cctx);
7486 
7487     // Below the ":for" scope drop the "expr" list from the stack.
7488     if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
7489 	return NULL;
7490 
7491     vim_free(scope);
7492 
7493     return arg;
7494 }
7495 
7496 /*
7497  * compile "while expr"
7498  *
7499  * Produces instructions:
7500  * top:  EVAL expr		Push result of "expr"
7501  *       JUMP_IF_FALSE end	jump if false
7502  *       ... body ...
7503  *       JUMP top		Jump back to repeat
7504  * end:
7505  *
7506  */
7507     static char_u *
7508 compile_while(char_u *arg, cctx_T *cctx)
7509 {
7510     char_u	*p = arg;
7511     scope_T	*scope;
7512 
7513     scope = new_scope(cctx, WHILE_SCOPE);
7514     if (scope == NULL)
7515 	return NULL;
7516 
7517     // "endwhile" jumps back here, one before when profiling or using cmdmods
7518     scope->se_u.se_while.ws_top_label = current_instr_idx(cctx);
7519 
7520     // compile "expr"
7521     if (compile_expr0(&p, cctx) == FAIL)
7522 	return NULL;
7523     if (!ends_excmd2(arg, skipwhite(p)))
7524     {
7525 	semsg(_(e_trailing_arg), p);
7526 	return NULL;
7527     }
7528 
7529     if (bool_on_stack(cctx) == FAIL)
7530 	return FAIL;
7531 
7532     // CMDMOD_REV must come before the jump
7533     generate_undo_cmdmods(cctx);
7534 
7535     // "while_end" is set when ":endwhile" is found
7536     if (compile_jump_to_end(&scope->se_u.se_while.ws_end_label,
7537 						  JUMP_IF_FALSE, cctx) == FAIL)
7538 	return FAIL;
7539 
7540     return p;
7541 }
7542 
7543 /*
7544  * compile "endwhile"
7545  */
7546     static char_u *
7547 compile_endwhile(char_u *arg, cctx_T *cctx)
7548 {
7549     scope_T	*scope = cctx->ctx_scope;
7550     garray_T	*instr = &cctx->ctx_instr;
7551 
7552     if (misplaced_cmdmod(cctx))
7553 	return NULL;
7554     if (scope == NULL || scope->se_type != WHILE_SCOPE)
7555     {
7556 	emsg(_(e_while));
7557 	return NULL;
7558     }
7559     cctx->ctx_scope = scope->se_outer;
7560     unwind_locals(cctx, scope->se_local_count);
7561 
7562 #ifdef FEAT_PROFILE
7563     // count the endwhile before jumping
7564     may_generate_prof_end(cctx, cctx->ctx_lnum);
7565 #endif
7566 
7567     // At end of ":for" scope jump back to the FOR instruction.
7568     generate_JUMP(cctx, JUMP_ALWAYS, scope->se_u.se_while.ws_top_label);
7569 
7570     // Fill in the "end" label in the WHILE statement so it can jump here.
7571     // And in any jumps for ":break"
7572     compile_fill_jump_to_end(&scope->se_u.se_while.ws_end_label,
7573 							  instr->ga_len, cctx);
7574 
7575     vim_free(scope);
7576 
7577     return arg;
7578 }
7579 
7580 /*
7581  * compile "continue"
7582  */
7583     static char_u *
7584 compile_continue(char_u *arg, cctx_T *cctx)
7585 {
7586     scope_T	*scope = cctx->ctx_scope;
7587     int		try_scopes = 0;
7588     int		loop_label;
7589 
7590     for (;;)
7591     {
7592 	if (scope == NULL)
7593 	{
7594 	    emsg(_(e_continue));
7595 	    return NULL;
7596 	}
7597 	if (scope->se_type == FOR_SCOPE)
7598 	{
7599 	    loop_label = scope->se_u.se_for.fs_top_label;
7600 	    break;
7601 	}
7602 	if (scope->se_type == WHILE_SCOPE)
7603 	{
7604 	    loop_label = scope->se_u.se_while.ws_top_label;
7605 	    break;
7606 	}
7607 	if (scope->se_type == TRY_SCOPE)
7608 	    ++try_scopes;
7609 	scope = scope->se_outer;
7610     }
7611 
7612     if (try_scopes > 0)
7613 	// Inside one or more try/catch blocks we first need to jump to the
7614 	// "finally" or "endtry" to cleanup.
7615 	generate_TRYCONT(cctx, try_scopes, loop_label);
7616     else
7617 	// Jump back to the FOR or WHILE instruction.
7618 	generate_JUMP(cctx, JUMP_ALWAYS, loop_label);
7619 
7620     return arg;
7621 }
7622 
7623 /*
7624  * compile "break"
7625  */
7626     static char_u *
7627 compile_break(char_u *arg, cctx_T *cctx)
7628 {
7629     scope_T	*scope = cctx->ctx_scope;
7630     endlabel_T	**el;
7631 
7632     for (;;)
7633     {
7634 	if (scope == NULL)
7635 	{
7636 	    emsg(_(e_break));
7637 	    return NULL;
7638 	}
7639 	if (scope->se_type == FOR_SCOPE || scope->se_type == WHILE_SCOPE)
7640 	    break;
7641 	scope = scope->se_outer;
7642     }
7643 
7644     // Jump to the end of the FOR or WHILE loop.
7645     if (scope->se_type == FOR_SCOPE)
7646 	el = &scope->se_u.se_for.fs_end_label;
7647     else
7648 	el = &scope->se_u.se_while.ws_end_label;
7649     if (compile_jump_to_end(el, JUMP_ALWAYS, cctx) == FAIL)
7650 	return FAIL;
7651 
7652     return arg;
7653 }
7654 
7655 /*
7656  * compile "{" start of block
7657  */
7658     static char_u *
7659 compile_block(char_u *arg, cctx_T *cctx)
7660 {
7661     if (new_scope(cctx, BLOCK_SCOPE) == NULL)
7662 	return NULL;
7663     return skipwhite(arg + 1);
7664 }
7665 
7666 /*
7667  * compile end of block: drop one scope
7668  */
7669     static void
7670 compile_endblock(cctx_T *cctx)
7671 {
7672     scope_T	*scope = cctx->ctx_scope;
7673 
7674     cctx->ctx_scope = scope->se_outer;
7675     unwind_locals(cctx, scope->se_local_count);
7676     vim_free(scope);
7677 }
7678 
7679 /*
7680  * compile "try"
7681  * Creates a new scope for the try-endtry, pointing to the first catch and
7682  * finally.
7683  * Creates another scope for the "try" block itself.
7684  * TRY instruction sets up exception handling at runtime.
7685  *
7686  *	"try"
7687  *	    TRY -> catch1, -> finally  push trystack entry
7688  *	    ... try block
7689  *	"throw {exception}"
7690  *	    EVAL {exception}
7691  *	    THROW		create exception
7692  *	    ... try block
7693  *	" catch {expr}"
7694  *	    JUMP -> finally
7695  * catch1:  PUSH exception
7696  *	    EVAL {expr}
7697  *	    MATCH
7698  *	    JUMP nomatch -> catch2
7699  *	    CATCH   remove exception
7700  *	    ... catch block
7701  *	" catch"
7702  *	    JUMP -> finally
7703  * catch2:  CATCH   remove exception
7704  *	    ... catch block
7705  *	" finally"
7706  * finally:
7707  *	    ... finally block
7708  *	" endtry"
7709  *	    ENDTRY  pop trystack entry, may rethrow
7710  */
7711     static char_u *
7712 compile_try(char_u *arg, cctx_T *cctx)
7713 {
7714     garray_T	*instr = &cctx->ctx_instr;
7715     scope_T	*try_scope;
7716     scope_T	*scope;
7717 
7718     if (misplaced_cmdmod(cctx))
7719 	return NULL;
7720 
7721     // scope that holds the jumps that go to catch/finally/endtry
7722     try_scope = new_scope(cctx, TRY_SCOPE);
7723     if (try_scope == NULL)
7724 	return NULL;
7725 
7726     if (cctx->ctx_skip != SKIP_YES)
7727     {
7728 	isn_T	*isn;
7729 
7730 	// "try_catch" is set when the first ":catch" is found or when no catch
7731 	// is found and ":finally" is found.
7732 	// "try_finally" is set when ":finally" is found
7733 	// "try_endtry" is set when ":endtry" is found
7734 	try_scope->se_u.se_try.ts_try_label = instr->ga_len;
7735 	if ((isn = generate_instr(cctx, ISN_TRY)) == NULL)
7736 	    return NULL;
7737 	isn->isn_arg.try.try_ref = ALLOC_CLEAR_ONE(tryref_T);
7738 	if (isn->isn_arg.try.try_ref == NULL)
7739 	    return NULL;
7740     }
7741 
7742     // scope for the try block itself
7743     scope = new_scope(cctx, BLOCK_SCOPE);
7744     if (scope == NULL)
7745 	return NULL;
7746 
7747     return arg;
7748 }
7749 
7750 /*
7751  * compile "catch {expr}"
7752  */
7753     static char_u *
7754 compile_catch(char_u *arg, cctx_T *cctx UNUSED)
7755 {
7756     scope_T	*scope = cctx->ctx_scope;
7757     garray_T	*instr = &cctx->ctx_instr;
7758     char_u	*p;
7759     isn_T	*isn;
7760 
7761     if (misplaced_cmdmod(cctx))
7762 	return NULL;
7763 
7764     // end block scope from :try or :catch
7765     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
7766 	compile_endblock(cctx);
7767     scope = cctx->ctx_scope;
7768 
7769     // Error if not in a :try scope
7770     if (scope == NULL || scope->se_type != TRY_SCOPE)
7771     {
7772 	emsg(_(e_catch));
7773 	return NULL;
7774     }
7775 
7776     if (scope->se_u.se_try.ts_caught_all)
7777     {
7778 	emsg(_(e_catch_unreachable_after_catch_all));
7779 	return NULL;
7780     }
7781 
7782     if (cctx->ctx_skip != SKIP_YES)
7783     {
7784 #ifdef FEAT_PROFILE
7785 	// the profile-start should be after the jump
7786 	if (cctx->ctx_profiling && ((isn_T *)instr->ga_data)[instr->ga_len - 1]
7787 						   .isn_type == ISN_PROF_START)
7788 	    --instr->ga_len;
7789 #endif
7790 	// Jump from end of previous block to :finally or :endtry
7791 	if (compile_jump_to_end(&scope->se_u.se_try.ts_end_label,
7792 						    JUMP_ALWAYS, cctx) == FAIL)
7793 	    return NULL;
7794 
7795 	// End :try or :catch scope: set value in ISN_TRY instruction
7796 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
7797 	if (isn->isn_arg.try.try_ref->try_catch == 0)
7798 	    isn->isn_arg.try.try_ref->try_catch = instr->ga_len;
7799 	if (scope->se_u.se_try.ts_catch_label != 0)
7800 	{
7801 	    // Previous catch without match jumps here
7802 	    isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_catch_label;
7803 	    isn->isn_arg.jump.jump_where = instr->ga_len;
7804 	}
7805 #ifdef FEAT_PROFILE
7806 	if (cctx->ctx_profiling)
7807 	{
7808 	    // a "throw" that jumps here needs to be counted
7809 	    generate_instr(cctx, ISN_PROF_END);
7810 	    // the "catch" is also counted
7811 	    generate_instr(cctx, ISN_PROF_START);
7812 	}
7813 #endif
7814     }
7815 
7816     p = skipwhite(arg);
7817     if (ends_excmd2(arg, p))
7818     {
7819 	scope->se_u.se_try.ts_caught_all = TRUE;
7820 	scope->se_u.se_try.ts_catch_label = 0;
7821     }
7822     else
7823     {
7824 	char_u *end;
7825 	char_u *pat;
7826 	char_u *tofree = NULL;
7827 	int	dropped = 0;
7828 	int	len;
7829 
7830 	// Push v:exception, push {expr} and MATCH
7831 	generate_instr_type(cctx, ISN_PUSHEXC, &t_string);
7832 
7833 	end = skip_regexp_ex(p + 1, *p, TRUE, &tofree, &dropped, NULL);
7834 	if (*end != *p)
7835 	{
7836 	    semsg(_(e_separator_mismatch_str), p);
7837 	    vim_free(tofree);
7838 	    return FAIL;
7839 	}
7840 	if (tofree == NULL)
7841 	    len = (int)(end - (p + 1));
7842 	else
7843 	    len = (int)(end - tofree);
7844 	pat = vim_strnsave(tofree == NULL ? p + 1 : tofree, len);
7845 	vim_free(tofree);
7846 	p += len + 2 + dropped;
7847 	if (pat == NULL)
7848 	    return FAIL;
7849 	if (generate_PUSHS(cctx, pat) == FAIL)
7850 	    return FAIL;
7851 
7852 	if (generate_COMPARE(cctx, EXPR_MATCH, FALSE) == FAIL)
7853 	    return NULL;
7854 
7855 	scope->se_u.se_try.ts_catch_label = instr->ga_len;
7856 	if (generate_JUMP(cctx, JUMP_IF_FALSE, 0) == FAIL)
7857 	    return NULL;
7858     }
7859 
7860     if (cctx->ctx_skip != SKIP_YES && generate_instr(cctx, ISN_CATCH) == NULL)
7861 	return NULL;
7862 
7863     if (new_scope(cctx, BLOCK_SCOPE) == NULL)
7864 	return NULL;
7865     return p;
7866 }
7867 
7868     static char_u *
7869 compile_finally(char_u *arg, cctx_T *cctx)
7870 {
7871     scope_T	*scope = cctx->ctx_scope;
7872     garray_T	*instr = &cctx->ctx_instr;
7873     isn_T	*isn;
7874     int		this_instr;
7875 
7876     if (misplaced_cmdmod(cctx))
7877 	return NULL;
7878 
7879     // end block scope from :try or :catch
7880     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
7881 	compile_endblock(cctx);
7882     scope = cctx->ctx_scope;
7883 
7884     // Error if not in a :try scope
7885     if (scope == NULL || scope->se_type != TRY_SCOPE)
7886     {
7887 	emsg(_(e_finally));
7888 	return NULL;
7889     }
7890 
7891     // End :catch or :finally scope: set value in ISN_TRY instruction
7892     isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
7893     if (isn->isn_arg.try.try_ref->try_finally != 0)
7894     {
7895 	emsg(_(e_finally_dup));
7896 	return NULL;
7897     }
7898 
7899     this_instr = instr->ga_len;
7900 #ifdef FEAT_PROFILE
7901     if (cctx->ctx_profiling && ((isn_T *)instr->ga_data)[instr->ga_len - 1]
7902 						   .isn_type == ISN_PROF_START)
7903 	// jump to the profile start of the "finally"
7904 	--this_instr;
7905 #endif
7906 
7907     // Fill in the "end" label in jumps at the end of the blocks.
7908     compile_fill_jump_to_end(&scope->se_u.se_try.ts_end_label,
7909 							     this_instr, cctx);
7910 
7911     // If there is no :catch then an exception jumps to :finally.
7912     if (isn->isn_arg.try.try_ref->try_catch == 0)
7913 	isn->isn_arg.try.try_ref->try_catch = this_instr;
7914     isn->isn_arg.try.try_ref->try_finally = this_instr;
7915     if (scope->se_u.se_try.ts_catch_label != 0)
7916     {
7917 	// Previous catch without match jumps here
7918 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_catch_label;
7919 	isn->isn_arg.jump.jump_where = this_instr;
7920 	scope->se_u.se_try.ts_catch_label = 0;
7921     }
7922     if (generate_instr(cctx, ISN_FINALLY) == NULL)
7923 	return NULL;
7924 
7925     // TODO: set index in ts_finally_label jumps
7926 
7927     return arg;
7928 }
7929 
7930     static char_u *
7931 compile_endtry(char_u *arg, cctx_T *cctx)
7932 {
7933     scope_T	*scope = cctx->ctx_scope;
7934     garray_T	*instr = &cctx->ctx_instr;
7935     isn_T	*try_isn;
7936 
7937     if (misplaced_cmdmod(cctx))
7938 	return NULL;
7939 
7940     // end block scope from :catch or :finally
7941     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
7942 	compile_endblock(cctx);
7943     scope = cctx->ctx_scope;
7944 
7945     // Error if not in a :try scope
7946     if (scope == NULL || scope->se_type != TRY_SCOPE)
7947     {
7948 	if (scope == NULL)
7949 	    emsg(_(e_no_endtry));
7950 	else if (scope->se_type == WHILE_SCOPE)
7951 	    emsg(_(e_endwhile));
7952 	else if (scope->se_type == FOR_SCOPE)
7953 	    emsg(_(e_endfor));
7954 	else
7955 	    emsg(_(e_endif));
7956 	return NULL;
7957     }
7958 
7959     try_isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
7960     if (cctx->ctx_skip != SKIP_YES)
7961     {
7962 	if (try_isn->isn_arg.try.try_ref->try_catch == 0
7963 				      && try_isn->isn_arg.try.try_ref->try_finally == 0)
7964 	{
7965 	    emsg(_(e_missing_catch_or_finally));
7966 	    return NULL;
7967 	}
7968 
7969 #ifdef FEAT_PROFILE
7970     if (cctx->ctx_profiling && ((isn_T *)instr->ga_data)[instr->ga_len - 1]
7971 						   .isn_type == ISN_PROF_START)
7972 	// move the profile start after "endtry" so that it's not counted when
7973 	// the exception is rethrown.
7974 	--instr->ga_len;
7975 #endif
7976 
7977 	// Fill in the "end" label in jumps at the end of the blocks, if not
7978 	// done by ":finally".
7979 	compile_fill_jump_to_end(&scope->se_u.se_try.ts_end_label,
7980 							  instr->ga_len, cctx);
7981 
7982 	if (scope->se_u.se_try.ts_catch_label != 0)
7983 	{
7984 	    // Last catch without match jumps here
7985 	    isn_T *isn = ((isn_T *)instr->ga_data)
7986 					   + scope->se_u.se_try.ts_catch_label;
7987 	    isn->isn_arg.jump.jump_where = instr->ga_len;
7988 	}
7989     }
7990 
7991     compile_endblock(cctx);
7992 
7993     if (cctx->ctx_skip != SKIP_YES)
7994     {
7995 	// End :catch or :finally scope: set instruction index in ISN_TRY
7996 	// instruction
7997 	try_isn->isn_arg.try.try_ref->try_endtry = instr->ga_len;
7998 	if (cctx->ctx_skip != SKIP_YES
7999 				   && generate_instr(cctx, ISN_ENDTRY) == NULL)
8000 	    return NULL;
8001 #ifdef FEAT_PROFILE
8002 	if (cctx->ctx_profiling)
8003 	    generate_instr(cctx, ISN_PROF_START);
8004 #endif
8005     }
8006     return arg;
8007 }
8008 
8009 /*
8010  * compile "throw {expr}"
8011  */
8012     static char_u *
8013 compile_throw(char_u *arg, cctx_T *cctx UNUSED)
8014 {
8015     char_u *p = skipwhite(arg);
8016 
8017     if (compile_expr0(&p, cctx) == FAIL)
8018 	return NULL;
8019     if (cctx->ctx_skip == SKIP_YES)
8020 	return p;
8021     if (may_generate_2STRING(-1, cctx) == FAIL)
8022 	return NULL;
8023     if (generate_instr_drop(cctx, ISN_THROW, 1) == NULL)
8024 	return NULL;
8025 
8026     return p;
8027 }
8028 
8029 /*
8030  * compile "echo expr"
8031  * compile "echomsg expr"
8032  * compile "echoerr expr"
8033  * compile "execute expr"
8034  */
8035     static char_u *
8036 compile_mult_expr(char_u *arg, int cmdidx, cctx_T *cctx)
8037 {
8038     char_u	*p = arg;
8039     char_u	*prev = arg;
8040     int		count = 0;
8041 
8042     for (;;)
8043     {
8044 	if (ends_excmd2(prev, p))
8045 	    break;
8046 	if (compile_expr0(&p, cctx) == FAIL)
8047 	    return NULL;
8048 	++count;
8049 	prev = p;
8050 	p = skipwhite(p);
8051     }
8052 
8053     if (count > 0)
8054     {
8055 	if (cmdidx == CMD_echo || cmdidx == CMD_echon)
8056 	    generate_ECHO(cctx, cmdidx == CMD_echo, count);
8057 	else if (cmdidx == CMD_execute)
8058 	    generate_MULT_EXPR(cctx, ISN_EXECUTE, count);
8059 	else if (cmdidx == CMD_echomsg)
8060 	    generate_MULT_EXPR(cctx, ISN_ECHOMSG, count);
8061 	else
8062 	    generate_MULT_EXPR(cctx, ISN_ECHOERR, count);
8063     }
8064     return p;
8065 }
8066 
8067 /*
8068  * If "eap" has a range that is not a constant generate an ISN_RANGE
8069  * instruction to compute it and return OK.
8070  * Otherwise return FAIL, the caller must deal with any range.
8071  */
8072     static int
8073 compile_variable_range(exarg_T *eap, cctx_T *cctx)
8074 {
8075     char_u *range_end = skip_range(eap->cmd, TRUE, NULL);
8076     char_u *p = skipdigits(eap->cmd);
8077 
8078     if (p == range_end)
8079 	return FAIL;
8080     return generate_RANGE(cctx, vim_strnsave(eap->cmd, range_end - eap->cmd));
8081 }
8082 
8083 /*
8084  * :put r
8085  * :put ={expr}
8086  */
8087     static char_u *
8088 compile_put(char_u *arg, exarg_T *eap, cctx_T *cctx)
8089 {
8090     char_u	*line = arg;
8091     linenr_T	lnum;
8092     char	*errormsg;
8093     int		above = eap->forceit;
8094 
8095     eap->regname = *line;
8096 
8097     if (eap->regname == '=')
8098     {
8099 	char_u *p = line + 1;
8100 
8101 	if (compile_expr0(&p, cctx) == FAIL)
8102 	    return NULL;
8103 	line = p;
8104     }
8105     else if (eap->regname != NUL)
8106 	++line;
8107 
8108     if (compile_variable_range(eap, cctx) == OK)
8109     {
8110 	lnum = above ? LNUM_VARIABLE_RANGE_ABOVE : LNUM_VARIABLE_RANGE;
8111     }
8112     else
8113     {
8114 	// Either no range or a number.
8115 	// "errormsg" will not be set because the range is ADDR_LINES.
8116 	if (parse_cmd_address(eap, &errormsg, FALSE) == FAIL)
8117 	    // cannot happen
8118 	    return NULL;
8119 	if (eap->addr_count == 0)
8120 	    lnum = -1;
8121 	else
8122 	    lnum = eap->line2;
8123 	if (above)
8124 	    --lnum;
8125     }
8126 
8127     generate_PUT(cctx, eap->regname, lnum);
8128     return line;
8129 }
8130 
8131 /*
8132  * A command that is not compiled, execute with legacy code.
8133  */
8134     static char_u *
8135 compile_exec(char_u *line, exarg_T *eap, cctx_T *cctx)
8136 {
8137     char_u  *p;
8138     int	    has_expr = FALSE;
8139     char_u  *nextcmd = (char_u *)"";
8140 
8141     if (cctx->ctx_skip == SKIP_YES)
8142 	goto theend;
8143 
8144     if (eap->cmdidx >= 0 && eap->cmdidx < CMD_SIZE)
8145     {
8146 	long	argt = eap->argt;
8147 	int	usefilter = FALSE;
8148 
8149 	has_expr = argt & (EX_XFILE | EX_EXPAND);
8150 
8151 	// If the command can be followed by a bar, find the bar and truncate
8152 	// it, so that the following command can be compiled.
8153 	// The '|' is overwritten with a NUL, it is put back below.
8154 	if ((eap->cmdidx == CMD_write || eap->cmdidx == CMD_read)
8155 							   && *eap->arg == '!')
8156 	    // :w !filter or :r !filter or :r! filter
8157 	    usefilter = TRUE;
8158 	if ((argt & EX_TRLBAR) && !usefilter)
8159 	{
8160 	    eap->argt = argt;
8161 	    separate_nextcmd(eap);
8162 	    if (eap->nextcmd != NULL)
8163 		nextcmd = eap->nextcmd;
8164 	}
8165 	else if (eap->cmdidx == CMD_wincmd)
8166 	{
8167 	    p = eap->arg;
8168 	    if (*p != NUL)
8169 		++p;
8170 	    if (*p == 'g' || *p == Ctrl_G)
8171 		++p;
8172 	    p = skipwhite(p);
8173 	    if (*p == '|')
8174 	    {
8175 		*p = NUL;
8176 		nextcmd = p + 1;
8177 	    }
8178 	}
8179     }
8180 
8181     if (eap->cmdidx == CMD_syntax && STRNCMP(eap->arg, "include ", 8) == 0)
8182     {
8183 	// expand filename in "syntax include [@group] filename"
8184 	has_expr = TRUE;
8185 	eap->arg = skipwhite(eap->arg + 7);
8186 	if (*eap->arg == '@')
8187 	    eap->arg = skiptowhite(eap->arg);
8188     }
8189 
8190     if ((eap->cmdidx == CMD_global || eap->cmdidx == CMD_vglobal)
8191 						       && STRLEN(eap->arg) > 4)
8192     {
8193 	int delim = *eap->arg;
8194 
8195 	p = skip_regexp_ex(eap->arg + 1, delim, TRUE, NULL, NULL, NULL);
8196 	if (*p == delim)
8197 	{
8198 	    eap->arg = p + 1;
8199 	    has_expr = TRUE;
8200 	}
8201     }
8202 
8203     if (eap->cmdidx == CMD_folddoopen || eap->cmdidx == CMD_folddoclosed)
8204     {
8205 	// TODO: should only expand when appropriate for the command
8206 	eap->arg = skiptowhite(eap->arg);
8207 	has_expr = TRUE;
8208     }
8209 
8210     if (has_expr && (p = (char_u *)strstr((char *)eap->arg, "`=")) != NULL)
8211     {
8212 	int	count = 0;
8213 	char_u	*start = skipwhite(line);
8214 
8215 	// :cmd xxx`=expr1`yyy`=expr2`zzz
8216 	// PUSHS ":cmd xxx"
8217 	// eval expr1
8218 	// PUSHS "yyy"
8219 	// eval expr2
8220 	// PUSHS "zzz"
8221 	// EXECCONCAT 5
8222 	for (;;)
8223 	{
8224 	    if (p > start)
8225 	    {
8226 		generate_PUSHS(cctx, vim_strnsave(start, p - start));
8227 		++count;
8228 	    }
8229 	    p += 2;
8230 	    if (compile_expr0(&p, cctx) == FAIL)
8231 		return NULL;
8232 	    may_generate_2STRING(-1, cctx);
8233 	    ++count;
8234 	    p = skipwhite(p);
8235 	    if (*p != '`')
8236 	    {
8237 		emsg(_(e_missing_backtick));
8238 		return NULL;
8239 	    }
8240 	    start = p + 1;
8241 
8242 	    p = (char_u *)strstr((char *)start, "`=");
8243 	    if (p == NULL)
8244 	    {
8245 		if (*skipwhite(start) != NUL)
8246 		{
8247 		    generate_PUSHS(cctx, vim_strsave(start));
8248 		    ++count;
8249 		}
8250 		break;
8251 	    }
8252 	}
8253 	generate_EXECCONCAT(cctx, count);
8254     }
8255     else
8256 	generate_EXEC(cctx, line);
8257 
8258 theend:
8259     if (*nextcmd != NUL)
8260     {
8261 	// the parser expects a pointer to the bar, put it back
8262 	--nextcmd;
8263 	*nextcmd = '|';
8264     }
8265 
8266     return nextcmd;
8267 }
8268 
8269 /*
8270  * Add a function to the list of :def functions.
8271  * This sets "ufunc->uf_dfunc_idx" but the function isn't compiled yet.
8272  */
8273     static int
8274 add_def_function(ufunc_T *ufunc)
8275 {
8276     dfunc_T *dfunc;
8277 
8278     if (def_functions.ga_len == 0)
8279     {
8280 	// The first position is not used, so that a zero uf_dfunc_idx means it
8281 	// wasn't set.
8282 	if (ga_grow(&def_functions, 1) == FAIL)
8283 	    return FAIL;
8284 	++def_functions.ga_len;
8285     }
8286 
8287     // Add the function to "def_functions".
8288     if (ga_grow(&def_functions, 1) == FAIL)
8289 	return FAIL;
8290     dfunc = ((dfunc_T *)def_functions.ga_data) + def_functions.ga_len;
8291     CLEAR_POINTER(dfunc);
8292     dfunc->df_idx = def_functions.ga_len;
8293     ufunc->uf_dfunc_idx = dfunc->df_idx;
8294     dfunc->df_ufunc = ufunc;
8295     dfunc->df_name = vim_strsave(ufunc->uf_name);
8296     ++dfunc->df_refcount;
8297     ++def_functions.ga_len;
8298     return OK;
8299 }
8300 
8301 /*
8302  * After ex_function() has collected all the function lines: parse and compile
8303  * the lines into instructions.
8304  * Adds the function to "def_functions".
8305  * When "check_return_type" is set then set ufunc->uf_ret_type to the type of
8306  * the return statement (used for lambda).  When uf_ret_type is already set
8307  * then check that it matches.
8308  * When "profiling" is true add ISN_PROF_START instructions.
8309  * "outer_cctx" is set for a nested function.
8310  * This can be used recursively through compile_lambda(), which may reallocate
8311  * "def_functions".
8312  * Returns OK or FAIL.
8313  */
8314     int
8315 compile_def_function(
8316 	ufunc_T	    *ufunc,
8317 	int	    check_return_type,
8318 	int	    profiling UNUSED,
8319 	cctx_T	    *outer_cctx)
8320 {
8321     char_u	*line = NULL;
8322     char_u	*p;
8323     char	*errormsg = NULL;	// error message
8324     cctx_T	cctx;
8325     garray_T	*instr;
8326     int		did_emsg_before = did_emsg;
8327     int		ret = FAIL;
8328     sctx_T	save_current_sctx = current_sctx;
8329     int		save_estack_compiling = estack_compiling;
8330     int		do_estack_push;
8331     int		new_def_function = FALSE;
8332 #ifdef FEAT_PROFILE
8333     int		prof_lnum = -1;
8334 #endif
8335 
8336     // When using a function that was compiled before: Free old instructions.
8337     // The index is reused.  Otherwise add a new entry in "def_functions".
8338     if (ufunc->uf_dfunc_idx > 0)
8339     {
8340 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
8341 							 + ufunc->uf_dfunc_idx;
8342 	delete_def_function_contents(dfunc, FALSE);
8343     }
8344     else
8345     {
8346 	if (add_def_function(ufunc) == FAIL)
8347 	    return FAIL;
8348 	new_def_function = TRUE;
8349     }
8350 
8351     ufunc->uf_def_status = UF_COMPILING;
8352 
8353     CLEAR_FIELD(cctx);
8354 
8355 #ifdef FEAT_PROFILE
8356     cctx.ctx_profiling = profiling;
8357 #endif
8358     cctx.ctx_ufunc = ufunc;
8359     cctx.ctx_lnum = -1;
8360     cctx.ctx_outer = outer_cctx;
8361     ga_init2(&cctx.ctx_locals, sizeof(lvar_T), 10);
8362     ga_init2(&cctx.ctx_type_stack, sizeof(type_T *), 50);
8363     ga_init2(&cctx.ctx_imports, sizeof(imported_T), 10);
8364     cctx.ctx_type_list = &ufunc->uf_type_list;
8365     ga_init2(&cctx.ctx_instr, sizeof(isn_T), 50);
8366     instr = &cctx.ctx_instr;
8367 
8368     // Set the context to the function, it may be compiled when called from
8369     // another script.  Set the script version to the most modern one.
8370     // The line number will be set in next_line_from_context().
8371     current_sctx = ufunc->uf_script_ctx;
8372     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
8373 
8374     // Make sure error messages are OK.
8375     do_estack_push = !estack_top_is_ufunc(ufunc, 1);
8376     if (do_estack_push)
8377 	estack_push_ufunc(ufunc, 1);
8378     estack_compiling = TRUE;
8379 
8380     if (ufunc->uf_def_args.ga_len > 0)
8381     {
8382 	int	count = ufunc->uf_def_args.ga_len;
8383 	int	first_def_arg = ufunc->uf_args.ga_len - count;
8384 	int	uf_args_len = ufunc->uf_args.ga_len;
8385 	int	i;
8386 	char_u	*arg;
8387 	int	off = STACK_FRAME_SIZE + (ufunc->uf_va_name != NULL ? 1 : 0);
8388 	int	did_set_arg_type = FALSE;
8389 
8390 	// Produce instructions for the default values of optional arguments.
8391 	SOURCING_LNUM = 0;  // line number unknown
8392 	for (i = 0; i < count; ++i)
8393 	{
8394 	    garray_T	*stack = &cctx.ctx_type_stack;
8395 	    type_T	*val_type;
8396 	    int		arg_idx = first_def_arg + i;
8397 	    where_T	where;
8398 	    int		r;
8399 	    int		jump_instr_idx = instr->ga_len;
8400 	    isn_T	*isn;
8401 
8402 	    // Use a JUMP_IF_ARG_SET instruction to skip if the value was given.
8403 	    if (generate_JUMP_IF_ARG_SET(&cctx, i - count - off) == FAIL)
8404 		goto erret;
8405 
8406 	    // Make sure later arguments are not found.
8407 	    ufunc->uf_args.ga_len = i;
8408 
8409 	    arg = ((char_u **)(ufunc->uf_def_args.ga_data))[i];
8410 	    r = compile_expr0(&arg, &cctx);
8411 
8412 	    ufunc->uf_args.ga_len = uf_args_len;
8413 	    if (r == FAIL)
8414 		goto erret;
8415 
8416 	    // If no type specified use the type of the default value.
8417 	    // Otherwise check that the default value type matches the
8418 	    // specified type.
8419 	    val_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
8420 	    where.wt_index = arg_idx + 1;
8421 	    where.wt_variable = FALSE;
8422 	    if (ufunc->uf_arg_types[arg_idx] == &t_unknown)
8423 	    {
8424 		did_set_arg_type = TRUE;
8425 		ufunc->uf_arg_types[arg_idx] = val_type;
8426 	    }
8427 	    else if (check_type(ufunc->uf_arg_types[arg_idx], val_type,
8428 							  TRUE, where) == FAIL)
8429 		goto erret;
8430 
8431 	    if (generate_STORE(&cctx, ISN_STORE, i - count - off, NULL) == FAIL)
8432 		goto erret;
8433 
8434 	    // set instruction index in JUMP_IF_ARG_SET to here
8435 	    isn = ((isn_T *)instr->ga_data) + jump_instr_idx;
8436 	    isn->isn_arg.jumparg.jump_where = instr->ga_len;
8437 	}
8438 
8439 	if (did_set_arg_type)
8440 	    set_function_type(ufunc);
8441     }
8442 
8443     /*
8444      * Loop over all the lines of the function and generate instructions.
8445      */
8446     for (;;)
8447     {
8448 	exarg_T	    ea;
8449 	int	    starts_with_colon = FALSE;
8450 	char_u	    *cmd;
8451 	cmdmod_T    local_cmdmod;
8452 
8453 	// Bail out on the first error to avoid a flood of errors and report
8454 	// the right line number when inside try/catch.
8455 	if (did_emsg_before != did_emsg)
8456 	    goto erret;
8457 
8458 	if (line != NULL && *line == '|')
8459 	    // the line continues after a '|'
8460 	    ++line;
8461 	else if (line != NULL && *skipwhite(line) != NUL
8462 		&& !(*line == '#' && (line == cctx.ctx_line_start
8463 						    || VIM_ISWHITE(line[-1]))))
8464 	{
8465 	    semsg(_(e_trailing_arg), line);
8466 	    goto erret;
8467 	}
8468 	else if (line != NULL && vim9_bad_comment(skipwhite(line)))
8469 	    goto erret;
8470 	else
8471 	{
8472 	    line = next_line_from_context(&cctx, FALSE);
8473 	    if (cctx.ctx_lnum >= ufunc->uf_lines.ga_len)
8474 	    {
8475 		// beyond the last line
8476 #ifdef FEAT_PROFILE
8477 		if (cctx.ctx_skip != SKIP_YES)
8478 		    may_generate_prof_end(&cctx, prof_lnum);
8479 #endif
8480 		break;
8481 	    }
8482 	}
8483 
8484 	CLEAR_FIELD(ea);
8485 	ea.cmdlinep = &line;
8486 	ea.cmd = skipwhite(line);
8487 
8488 	if (*ea.cmd == '#')
8489 	{
8490 	    // "#" starts a comment
8491 	    line = (char_u *)"";
8492 	    continue;
8493 	}
8494 
8495 #ifdef FEAT_PROFILE
8496 	if (cctx.ctx_profiling && cctx.ctx_lnum != prof_lnum &&
8497 						     cctx.ctx_skip != SKIP_YES)
8498 	{
8499 	    may_generate_prof_end(&cctx, prof_lnum);
8500 
8501 	    prof_lnum = cctx.ctx_lnum;
8502 	    generate_instr(&cctx, ISN_PROF_START);
8503 	}
8504 #endif
8505 
8506 	// Some things can be recognized by the first character.
8507 	switch (*ea.cmd)
8508 	{
8509 	    case '}':
8510 		{
8511 		    // "}" ends a block scope
8512 		    scopetype_T stype = cctx.ctx_scope == NULL
8513 					  ? NO_SCOPE : cctx.ctx_scope->se_type;
8514 
8515 		    if (stype == BLOCK_SCOPE)
8516 		    {
8517 			compile_endblock(&cctx);
8518 			line = ea.cmd;
8519 		    }
8520 		    else
8521 		    {
8522 			emsg(_(e_using_rcurly_outside_if_block_scope));
8523 			goto erret;
8524 		    }
8525 		    if (line != NULL)
8526 			line = skipwhite(ea.cmd + 1);
8527 		    continue;
8528 		}
8529 
8530 	    case '{':
8531 		// "{" starts a block scope
8532 		// "{'a': 1}->func() is something else
8533 		if (ends_excmd(*skipwhite(ea.cmd + 1)))
8534 		{
8535 		    line = compile_block(ea.cmd, &cctx);
8536 		    continue;
8537 		}
8538 		break;
8539 	}
8540 
8541 	/*
8542 	 * COMMAND MODIFIERS
8543 	 */
8544 	cctx.ctx_has_cmdmod = FALSE;
8545 	if (parse_command_modifiers(&ea, &errormsg, &local_cmdmod, FALSE)
8546 								       == FAIL)
8547 	{
8548 	    if (errormsg != NULL)
8549 		goto erret;
8550 	    // empty line or comment
8551 	    line = (char_u *)"";
8552 	    continue;
8553 	}
8554 	generate_cmdmods(&cctx, &local_cmdmod);
8555 	undo_cmdmod(&local_cmdmod);
8556 
8557 	// Check if there was a colon after the last command modifier or before
8558 	// the current position.
8559 	for (p = ea.cmd; p >= line; --p)
8560 	{
8561 	    if (*p == ':')
8562 		starts_with_colon = TRUE;
8563 	    if (p < ea.cmd && !VIM_ISWHITE(*p))
8564 		break;
8565 	}
8566 
8567 	// Skip ":call" to get to the function name.
8568 	p = ea.cmd;
8569 	if (checkforcmd(&ea.cmd, "call", 3))
8570 	{
8571 	    if (*ea.cmd == '(')
8572 		// not for "call()"
8573 		ea.cmd = p;
8574 	    else
8575 		ea.cmd = skipwhite(ea.cmd);
8576 	}
8577 
8578 	if (!starts_with_colon)
8579 	{
8580 	    int	    assign;
8581 
8582 	    // Check for assignment after command modifiers.
8583 	    assign = may_compile_assignment(&ea, &line, &cctx);
8584 	    if (assign == OK)
8585 		goto nextline;
8586 	    if (assign == FAIL)
8587 		goto erret;
8588 	}
8589 
8590 	/*
8591 	 * COMMAND after range
8592 	 * 'text'->func() should not be confused with 'a mark
8593 	 */
8594 	cmd = ea.cmd;
8595 	if (*cmd != '\'' || starts_with_colon)
8596 	{
8597 	    ea.cmd = skip_range(ea.cmd, TRUE, NULL);
8598 	    if (ea.cmd > cmd)
8599 	    {
8600 		if (!starts_with_colon)
8601 		{
8602 		    semsg(_(e_colon_required_before_range_str), cmd);
8603 		    goto erret;
8604 		}
8605 		ea.addr_count = 1;
8606 		if (ends_excmd2(line, ea.cmd))
8607 		{
8608 		    // A range without a command: jump to the line.
8609 		    // TODO: compile to a more efficient command, possibly
8610 		    // calling parse_cmd_address().
8611 		    ea.cmdidx = CMD_SIZE;
8612 		    line = compile_exec(line, &ea, &cctx);
8613 		    goto nextline;
8614 		}
8615 	    }
8616 	}
8617 	p = find_ex_command(&ea, NULL, starts_with_colon
8618 						  ? NULL : item_exists, &cctx);
8619 
8620 	if (p == NULL)
8621 	{
8622 	    if (cctx.ctx_skip != SKIP_YES)
8623 		emsg(_(e_ambiguous_use_of_user_defined_command));
8624 	    goto erret;
8625 	}
8626 
8627 	if (p == ea.cmd && ea.cmdidx != CMD_SIZE)
8628 	{
8629 	    if (cctx.ctx_skip == SKIP_YES)
8630 	    {
8631 		line += STRLEN(line);
8632 		goto nextline;
8633 	    }
8634 
8635 	    // Expression or function call.
8636 	    if (ea.cmdidx != CMD_eval)
8637 	    {
8638 		// CMD_var cannot happen, compile_assignment() above would be
8639 		// used.  Most likely an assignment to a non-existing variable.
8640 		semsg(_(e_command_not_recognized_str), ea.cmd);
8641 		goto erret;
8642 	    }
8643 	}
8644 
8645 	if (cctx.ctx_had_return
8646 		&& ea.cmdidx != CMD_elseif
8647 		&& ea.cmdidx != CMD_else
8648 		&& ea.cmdidx != CMD_endif
8649 		&& ea.cmdidx != CMD_endfor
8650 		&& ea.cmdidx != CMD_endwhile
8651 		&& ea.cmdidx != CMD_catch
8652 		&& ea.cmdidx != CMD_finally
8653 		&& ea.cmdidx != CMD_endtry)
8654 	{
8655 	    emsg(_(e_unreachable_code_after_return));
8656 	    goto erret;
8657 	}
8658 
8659 	p = skipwhite(p);
8660 	if (ea.cmdidx != CMD_SIZE
8661 			    && ea.cmdidx != CMD_write && ea.cmdidx != CMD_read)
8662 	{
8663 	    if (ea.cmdidx >= 0)
8664 		ea.argt = excmd_get_argt(ea.cmdidx);
8665 	    if ((ea.argt & EX_BANG) && *p == '!')
8666 	    {
8667 		ea.forceit = TRUE;
8668 		p = skipwhite(p + 1);
8669 	    }
8670 	}
8671 
8672 	switch (ea.cmdidx)
8673 	{
8674 	    case CMD_def:
8675 		    ea.arg = p;
8676 		    line = compile_nested_function(&ea, &cctx);
8677 		    break;
8678 
8679 	    case CMD_function:
8680 		    // TODO: should we allow this, e.g. to declare a global
8681 		    // function?
8682 		    emsg(_(e_cannot_use_function_inside_def));
8683 		    goto erret;
8684 
8685 	    case CMD_return:
8686 		    line = compile_return(p, check_return_type, &cctx);
8687 		    cctx.ctx_had_return = TRUE;
8688 		    break;
8689 
8690 	    case CMD_let:
8691 		    emsg(_(e_cannot_use_let_in_vim9_script));
8692 		    break;
8693 	    case CMD_var:
8694 	    case CMD_final:
8695 	    case CMD_const:
8696 		    line = compile_assignment(p, &ea, ea.cmdidx, &cctx);
8697 		    if (line == p)
8698 			line = NULL;
8699 		    break;
8700 
8701 	    case CMD_unlet:
8702 	    case CMD_unlockvar:
8703 	    case CMD_lockvar:
8704 		    line = compile_unletlock(p, &ea, &cctx);
8705 		    break;
8706 
8707 	    case CMD_import:
8708 		    line = compile_import(p, &cctx);
8709 		    break;
8710 
8711 	    case CMD_if:
8712 		    line = compile_if(p, &cctx);
8713 		    break;
8714 	    case CMD_elseif:
8715 		    line = compile_elseif(p, &cctx);
8716 		    cctx.ctx_had_return = FALSE;
8717 		    break;
8718 	    case CMD_else:
8719 		    line = compile_else(p, &cctx);
8720 		    cctx.ctx_had_return = FALSE;
8721 		    break;
8722 	    case CMD_endif:
8723 		    line = compile_endif(p, &cctx);
8724 		    break;
8725 
8726 	    case CMD_while:
8727 		    line = compile_while(p, &cctx);
8728 		    break;
8729 	    case CMD_endwhile:
8730 		    line = compile_endwhile(p, &cctx);
8731 		    cctx.ctx_had_return = FALSE;
8732 		    break;
8733 
8734 	    case CMD_for:
8735 		    line = compile_for(p, &cctx);
8736 		    break;
8737 	    case CMD_endfor:
8738 		    line = compile_endfor(p, &cctx);
8739 		    cctx.ctx_had_return = FALSE;
8740 		    break;
8741 	    case CMD_continue:
8742 		    line = compile_continue(p, &cctx);
8743 		    break;
8744 	    case CMD_break:
8745 		    line = compile_break(p, &cctx);
8746 		    break;
8747 
8748 	    case CMD_try:
8749 		    line = compile_try(p, &cctx);
8750 		    break;
8751 	    case CMD_catch:
8752 		    line = compile_catch(p, &cctx);
8753 		    cctx.ctx_had_return = FALSE;
8754 		    break;
8755 	    case CMD_finally:
8756 		    line = compile_finally(p, &cctx);
8757 		    cctx.ctx_had_return = FALSE;
8758 		    break;
8759 	    case CMD_endtry:
8760 		    line = compile_endtry(p, &cctx);
8761 		    cctx.ctx_had_return = FALSE;
8762 		    break;
8763 	    case CMD_throw:
8764 		    line = compile_throw(p, &cctx);
8765 		    break;
8766 
8767 	    case CMD_eval:
8768 		    if (compile_expr0(&p, &cctx) == FAIL)
8769 			goto erret;
8770 
8771 		    // drop the result
8772 		    generate_instr_drop(&cctx, ISN_DROP, 1);
8773 
8774 		    line = skipwhite(p);
8775 		    break;
8776 
8777 	    case CMD_echo:
8778 	    case CMD_echon:
8779 	    case CMD_execute:
8780 	    case CMD_echomsg:
8781 	    case CMD_echoerr:
8782 		    line = compile_mult_expr(p, ea.cmdidx, &cctx);
8783 		    break;
8784 
8785 	    case CMD_put:
8786 		    ea.cmd = cmd;
8787 		    line = compile_put(p, &ea, &cctx);
8788 		    break;
8789 
8790 	    // TODO: any other commands with an expression argument?
8791 
8792 	    case CMD_append:
8793 	    case CMD_change:
8794 	    case CMD_insert:
8795 	    case CMD_k:
8796 	    case CMD_t:
8797 	    case CMD_xit:
8798 		    not_in_vim9(&ea);
8799 		    goto erret;
8800 
8801 	    case CMD_SIZE:
8802 		    if (cctx.ctx_skip != SKIP_YES)
8803 		    {
8804 			semsg(_(e_invalid_command_str), ea.cmd);
8805 			goto erret;
8806 		    }
8807 		    // We don't check for a next command here.
8808 		    line = (char_u *)"";
8809 		    break;
8810 
8811 	    default:
8812 		    if (cctx.ctx_skip == SKIP_YES)
8813 		    {
8814 			// We don't check for a next command here.
8815 			line = (char_u *)"";
8816 		    }
8817 		    else
8818 		    {
8819 			// Not recognized, execute with do_cmdline_cmd().
8820 			ea.arg = p;
8821 			line = compile_exec(line, &ea, &cctx);
8822 		    }
8823 		    break;
8824 	}
8825 nextline:
8826 	if (line == NULL)
8827 	    goto erret;
8828 	line = skipwhite(line);
8829 
8830 	// Undo any command modifiers.
8831 	generate_undo_cmdmods(&cctx);
8832 
8833 	if (cctx.ctx_type_stack.ga_len < 0)
8834 	{
8835 	    iemsg("Type stack underflow");
8836 	    goto erret;
8837 	}
8838     }
8839 
8840     if (cctx.ctx_scope != NULL)
8841     {
8842 	if (cctx.ctx_scope->se_type == IF_SCOPE)
8843 	    emsg(_(e_endif));
8844 	else if (cctx.ctx_scope->se_type == WHILE_SCOPE)
8845 	    emsg(_(e_endwhile));
8846 	else if (cctx.ctx_scope->se_type == FOR_SCOPE)
8847 	    emsg(_(e_endfor));
8848 	else
8849 	    emsg(_(e_missing_rcurly));
8850 	goto erret;
8851     }
8852 
8853     if (!cctx.ctx_had_return)
8854     {
8855 	if (ufunc->uf_ret_type->tt_type != VAR_VOID)
8856 	{
8857 	    emsg(_(e_missing_return_statement));
8858 	    goto erret;
8859 	}
8860 
8861 	// Return zero if there is no return at the end.
8862 	generate_instr(&cctx, ISN_RETURN_ZERO);
8863     }
8864 
8865     {
8866 	dfunc_T	*dfunc = ((dfunc_T *)def_functions.ga_data)
8867 							 + ufunc->uf_dfunc_idx;
8868 	dfunc->df_deleted = FALSE;
8869 	dfunc->df_script_seq = current_sctx.sc_seq;
8870 #ifdef FEAT_PROFILE
8871 	if (cctx.ctx_profiling)
8872 	{
8873 	    dfunc->df_instr_prof = instr->ga_data;
8874 	    dfunc->df_instr_prof_count = instr->ga_len;
8875 	}
8876 	else
8877 #endif
8878 	{
8879 	    dfunc->df_instr = instr->ga_data;
8880 	    dfunc->df_instr_count = instr->ga_len;
8881 	}
8882 	dfunc->df_varcount = cctx.ctx_locals_count;
8883 	dfunc->df_has_closure = cctx.ctx_has_closure;
8884 	if (cctx.ctx_outer_used)
8885 	    ufunc->uf_flags |= FC_CLOSURE;
8886 	ufunc->uf_def_status = UF_COMPILED;
8887     }
8888 
8889     ret = OK;
8890 
8891 erret:
8892     if (ret == FAIL)
8893     {
8894 	int idx;
8895 	dfunc_T	*dfunc = ((dfunc_T *)def_functions.ga_data)
8896 							 + ufunc->uf_dfunc_idx;
8897 
8898 	for (idx = 0; idx < instr->ga_len; ++idx)
8899 	    delete_instr(((isn_T *)instr->ga_data) + idx);
8900 	ga_clear(instr);
8901 	VIM_CLEAR(dfunc->df_name);
8902 
8903 	// If using the last entry in the table and it was added above, we
8904 	// might as well remove it.
8905 	if (!dfunc->df_deleted && new_def_function
8906 			    && ufunc->uf_dfunc_idx == def_functions.ga_len - 1)
8907 	{
8908 	    --def_functions.ga_len;
8909 	    ufunc->uf_dfunc_idx = 0;
8910 	}
8911 	ufunc->uf_def_status = UF_NOT_COMPILED;
8912 
8913 	while (cctx.ctx_scope != NULL)
8914 	    drop_scope(&cctx);
8915 
8916 	// Don't execute this function body.
8917 	ga_clear_strings(&ufunc->uf_lines);
8918 
8919 	if (errormsg != NULL)
8920 	    emsg(errormsg);
8921 	else if (did_emsg == did_emsg_before)
8922 	    emsg(_(e_compiling_def_function_failed));
8923     }
8924 
8925     current_sctx = save_current_sctx;
8926     estack_compiling = save_estack_compiling;
8927     if (do_estack_push)
8928 	estack_pop();
8929 
8930     free_imported(&cctx);
8931     free_locals(&cctx);
8932     ga_clear(&cctx.ctx_type_stack);
8933     return ret;
8934 }
8935 
8936     void
8937 set_function_type(ufunc_T *ufunc)
8938 {
8939     int varargs = ufunc->uf_va_name != NULL;
8940     int argcount = ufunc->uf_args.ga_len;
8941 
8942     // Create a type for the function, with the return type and any
8943     // argument types.
8944     // A vararg is included in uf_args.ga_len but not in uf_arg_types.
8945     // The type is included in "tt_args".
8946     if (argcount > 0 || varargs)
8947     {
8948 	if (ufunc->uf_type_list.ga_itemsize == 0)
8949 	    ga_init2(&ufunc->uf_type_list, sizeof(type_T *), 10);
8950 	ufunc->uf_func_type = alloc_func_type(ufunc->uf_ret_type,
8951 					   argcount, &ufunc->uf_type_list);
8952 	// Add argument types to the function type.
8953 	if (func_type_add_arg_types(ufunc->uf_func_type,
8954 				    argcount + varargs,
8955 				    &ufunc->uf_type_list) == FAIL)
8956 	    return;
8957 	ufunc->uf_func_type->tt_argcount = argcount + varargs;
8958 	ufunc->uf_func_type->tt_min_argcount =
8959 				      argcount - ufunc->uf_def_args.ga_len;
8960 	if (ufunc->uf_arg_types == NULL)
8961 	{
8962 	    int i;
8963 
8964 	    // lambda does not have argument types.
8965 	    for (i = 0; i < argcount; ++i)
8966 		ufunc->uf_func_type->tt_args[i] = &t_any;
8967 	}
8968 	else
8969 	    mch_memmove(ufunc->uf_func_type->tt_args,
8970 			 ufunc->uf_arg_types, sizeof(type_T *) * argcount);
8971 	if (varargs)
8972 	{
8973 	    ufunc->uf_func_type->tt_args[argcount] =
8974 		    ufunc->uf_va_type == NULL ? &t_any : ufunc->uf_va_type;
8975 	    ufunc->uf_func_type->tt_flags = TTFLAG_VARARGS;
8976 	}
8977     }
8978     else
8979 	// No arguments, can use a predefined type.
8980 	ufunc->uf_func_type = get_func_type(ufunc->uf_ret_type,
8981 					   argcount, &ufunc->uf_type_list);
8982 }
8983 
8984 
8985 /*
8986  * Delete an instruction, free what it contains.
8987  */
8988     void
8989 delete_instr(isn_T *isn)
8990 {
8991     switch (isn->isn_type)
8992     {
8993 	case ISN_DEF:
8994 	case ISN_EXEC:
8995 	case ISN_LOADAUTO:
8996 	case ISN_LOADB:
8997 	case ISN_LOADENV:
8998 	case ISN_LOADG:
8999 	case ISN_LOADOPT:
9000 	case ISN_LOADT:
9001 	case ISN_LOADW:
9002 	case ISN_PUSHEXC:
9003 	case ISN_PUSHFUNC:
9004 	case ISN_PUSHS:
9005 	case ISN_RANGE:
9006 	case ISN_STOREAUTO:
9007 	case ISN_STOREB:
9008 	case ISN_STOREENV:
9009 	case ISN_STOREG:
9010 	case ISN_STORET:
9011 	case ISN_STOREW:
9012 	case ISN_STRINGMEMBER:
9013 	    vim_free(isn->isn_arg.string);
9014 	    break;
9015 
9016 	case ISN_LOADS:
9017 	case ISN_STORES:
9018 	    vim_free(isn->isn_arg.loadstore.ls_name);
9019 	    break;
9020 
9021 	case ISN_UNLET:
9022 	case ISN_UNLETENV:
9023 	    vim_free(isn->isn_arg.unlet.ul_name);
9024 	    break;
9025 
9026 	case ISN_STOREOPT:
9027 	    vim_free(isn->isn_arg.storeopt.so_name);
9028 	    break;
9029 
9030 	case ISN_PUSHBLOB:   // push blob isn_arg.blob
9031 	    blob_unref(isn->isn_arg.blob);
9032 	    break;
9033 
9034 	case ISN_PUSHJOB:
9035 #ifdef FEAT_JOB_CHANNEL
9036 	    job_unref(isn->isn_arg.job);
9037 #endif
9038 	    break;
9039 
9040 	case ISN_PUSHCHANNEL:
9041 #ifdef FEAT_JOB_CHANNEL
9042 	    channel_unref(isn->isn_arg.channel);
9043 #endif
9044 	    break;
9045 
9046 	case ISN_UCALL:
9047 	    vim_free(isn->isn_arg.ufunc.cuf_name);
9048 	    break;
9049 
9050 	case ISN_FUNCREF:
9051 	    {
9052 		dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
9053 					       + isn->isn_arg.funcref.fr_func;
9054 		ufunc_T *ufunc = dfunc->df_ufunc;
9055 
9056 		if (ufunc != NULL && func_name_refcount(ufunc->uf_name))
9057 		    func_ptr_unref(ufunc);
9058 	    }
9059 	    break;
9060 
9061 	case ISN_DCALL:
9062 	    {
9063 		dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
9064 					       + isn->isn_arg.dfunc.cdf_idx;
9065 
9066 		if (dfunc->df_ufunc != NULL
9067 			       && func_name_refcount(dfunc->df_ufunc->uf_name))
9068 		    func_ptr_unref(dfunc->df_ufunc);
9069 	    }
9070 	    break;
9071 
9072 	case ISN_NEWFUNC:
9073 	    {
9074 		char_u  *lambda = isn->isn_arg.newfunc.nf_lambda;
9075 		ufunc_T *ufunc = find_func_even_dead(lambda, TRUE, NULL);
9076 
9077 		if (ufunc != NULL)
9078 		{
9079 		    unlink_def_function(ufunc);
9080 		    func_ptr_unref(ufunc);
9081 		}
9082 
9083 		vim_free(lambda);
9084 		vim_free(isn->isn_arg.newfunc.nf_global);
9085 	    }
9086 	    break;
9087 
9088 	case ISN_CHECKTYPE:
9089 	case ISN_SETTYPE:
9090 	    free_type(isn->isn_arg.type.ct_type);
9091 	    break;
9092 
9093 	case ISN_CMDMOD:
9094 	    vim_regfree(isn->isn_arg.cmdmod.cf_cmdmod
9095 					       ->cmod_filter_regmatch.regprog);
9096 	    vim_free(isn->isn_arg.cmdmod.cf_cmdmod);
9097 	    break;
9098 
9099 	case ISN_LOADSCRIPT:
9100 	case ISN_STORESCRIPT:
9101 	    vim_free(isn->isn_arg.script.scriptref);
9102 	    break;
9103 
9104 	case ISN_TRY:
9105 	    vim_free(isn->isn_arg.try.try_ref);
9106 	    break;
9107 
9108 	case ISN_2BOOL:
9109 	case ISN_2STRING:
9110 	case ISN_2STRING_ANY:
9111 	case ISN_ADDBLOB:
9112 	case ISN_ADDLIST:
9113 	case ISN_ANYINDEX:
9114 	case ISN_ANYSLICE:
9115 	case ISN_BCALL:
9116 	case ISN_BLOBAPPEND:
9117 	case ISN_CATCH:
9118 	case ISN_CHECKLEN:
9119 	case ISN_CHECKNR:
9120 	case ISN_CMDMOD_REV:
9121 	case ISN_COMPAREANY:
9122 	case ISN_COMPAREBLOB:
9123 	case ISN_COMPAREBOOL:
9124 	case ISN_COMPAREDICT:
9125 	case ISN_COMPAREFLOAT:
9126 	case ISN_COMPAREFUNC:
9127 	case ISN_COMPARELIST:
9128 	case ISN_COMPARENR:
9129 	case ISN_COMPARESPECIAL:
9130 	case ISN_COMPARESTRING:
9131 	case ISN_CONCAT:
9132 	case ISN_COND2BOOL:
9133 	case ISN_DROP:
9134 	case ISN_ECHO:
9135 	case ISN_ECHOERR:
9136 	case ISN_ECHOMSG:
9137 	case ISN_ENDTRY:
9138 	case ISN_EXECCONCAT:
9139 	case ISN_EXECUTE:
9140 	case ISN_FINALLY:
9141 	case ISN_FOR:
9142 	case ISN_GETITEM:
9143 	case ISN_JUMP:
9144 	case ISN_JUMP_IF_ARG_SET:
9145 	case ISN_LISTAPPEND:
9146 	case ISN_LISTINDEX:
9147 	case ISN_LISTSLICE:
9148 	case ISN_LOAD:
9149 	case ISN_LOADBDICT:
9150 	case ISN_LOADGDICT:
9151 	case ISN_LOADOUTER:
9152 	case ISN_LOADREG:
9153 	case ISN_LOADTDICT:
9154 	case ISN_LOADV:
9155 	case ISN_LOADWDICT:
9156 	case ISN_LOCKCONST:
9157 	case ISN_MEMBER:
9158 	case ISN_NEGATENR:
9159 	case ISN_NEWDICT:
9160 	case ISN_NEWLIST:
9161 	case ISN_OPANY:
9162 	case ISN_OPFLOAT:
9163 	case ISN_OPNR:
9164 	case ISN_PCALL:
9165 	case ISN_PCALL_END:
9166 	case ISN_PROF_END:
9167 	case ISN_PROF_START:
9168 	case ISN_PUSHBOOL:
9169 	case ISN_PUSHF:
9170 	case ISN_PUSHNR:
9171 	case ISN_PUSHSPEC:
9172 	case ISN_PUT:
9173 	case ISN_RETURN:
9174 	case ISN_RETURN_ZERO:
9175 	case ISN_SHUFFLE:
9176 	case ISN_SLICE:
9177 	case ISN_STORE:
9178 	case ISN_STOREINDEX:
9179 	case ISN_STORENR:
9180 	case ISN_STOREOUTER:
9181 	case ISN_STOREREG:
9182 	case ISN_STOREV:
9183 	case ISN_STRINDEX:
9184 	case ISN_STRSLICE:
9185 	case ISN_THROW:
9186 	case ISN_TRYCONT:
9187 	case ISN_UNLETINDEX:
9188 	case ISN_UNLETRANGE:
9189 	case ISN_UNPACK:
9190 	    // nothing allocated
9191 	    break;
9192     }
9193 }
9194 
9195 /*
9196  * Free all instructions for "dfunc" except df_name.
9197  */
9198     static void
9199 delete_def_function_contents(dfunc_T *dfunc, int mark_deleted)
9200 {
9201     int idx;
9202 
9203     ga_clear(&dfunc->df_def_args_isn);
9204 
9205     if (dfunc->df_instr != NULL)
9206     {
9207 	for (idx = 0; idx < dfunc->df_instr_count; ++idx)
9208 	    delete_instr(dfunc->df_instr + idx);
9209 	VIM_CLEAR(dfunc->df_instr);
9210 	dfunc->df_instr = NULL;
9211     }
9212 #ifdef FEAT_PROFILE
9213     if (dfunc->df_instr_prof != NULL)
9214     {
9215 	for (idx = 0; idx < dfunc->df_instr_prof_count; ++idx)
9216 	    delete_instr(dfunc->df_instr_prof + idx);
9217 	VIM_CLEAR(dfunc->df_instr_prof);
9218 	dfunc->df_instr_prof = NULL;
9219     }
9220 #endif
9221 
9222     if (mark_deleted)
9223 	dfunc->df_deleted = TRUE;
9224     if (dfunc->df_ufunc != NULL)
9225 	dfunc->df_ufunc->uf_def_status = UF_NOT_COMPILED;
9226 }
9227 
9228 /*
9229  * When a user function is deleted, clear the contents of any associated def
9230  * function, unless another user function still uses it.
9231  * The position in def_functions can be re-used.
9232  */
9233     void
9234 unlink_def_function(ufunc_T *ufunc)
9235 {
9236     if (ufunc->uf_dfunc_idx > 0)
9237     {
9238 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
9239 							 + ufunc->uf_dfunc_idx;
9240 
9241 	if (--dfunc->df_refcount <= 0)
9242 	    delete_def_function_contents(dfunc, TRUE);
9243 	ufunc->uf_def_status = UF_NOT_COMPILED;
9244 	ufunc->uf_dfunc_idx = 0;
9245 	if (dfunc->df_ufunc == ufunc)
9246 	    dfunc->df_ufunc = NULL;
9247     }
9248 }
9249 
9250 /*
9251  * Used when a user function refers to an existing dfunc.
9252  */
9253     void
9254 link_def_function(ufunc_T *ufunc)
9255 {
9256     if (ufunc->uf_dfunc_idx > 0)
9257     {
9258 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
9259 							 + ufunc->uf_dfunc_idx;
9260 
9261 	++dfunc->df_refcount;
9262     }
9263 }
9264 
9265 #if defined(EXITFREE) || defined(PROTO)
9266 /*
9267  * Free all functions defined with ":def".
9268  */
9269     void
9270 free_def_functions(void)
9271 {
9272     int idx;
9273 
9274     for (idx = 0; idx < def_functions.ga_len; ++idx)
9275     {
9276 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data) + idx;
9277 
9278 	delete_def_function_contents(dfunc, TRUE);
9279 	vim_free(dfunc->df_name);
9280     }
9281 
9282     ga_clear(&def_functions);
9283 }
9284 #endif
9285 
9286 
9287 #endif // FEAT_EVAL
9288