xref: /vim-8.2.3635/src/vim9compile.c (revision fa57335e)
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_had_return;	    // every block ends in :return
48     int		is_if_label;	    // instruction idx at IF or ELSEIF
49     endlabel_T	*is_end_label;	    // instructions to set end label
50 } ifscope_T;
51 
52 /*
53  * info specific for the scope of :while
54  */
55 typedef struct {
56     int		ws_top_label;	    // instruction idx at WHILE
57     endlabel_T	*ws_end_label;	    // instructions to set end
58 } whilescope_T;
59 
60 /*
61  * info specific for the scope of :for
62  */
63 typedef struct {
64     int		fs_top_label;	    // instruction idx at FOR
65     endlabel_T	*fs_end_label;	    // break instructions
66 } forscope_T;
67 
68 /*
69  * info specific for the scope of :try
70  */
71 typedef struct {
72     int		ts_try_label;	    // instruction idx at TRY
73     endlabel_T	*ts_end_label;	    // jump to :finally or :endtry
74     int		ts_catch_label;	    // instruction idx of last CATCH
75     int		ts_caught_all;	    // "catch" without argument encountered
76 } tryscope_T;
77 
78 typedef enum {
79     NO_SCOPE,
80     IF_SCOPE,
81     WHILE_SCOPE,
82     FOR_SCOPE,
83     TRY_SCOPE,
84     BLOCK_SCOPE
85 } scopetype_T;
86 
87 /*
88  * Info for one scope, pointed to by "ctx_scope".
89  */
90 typedef struct scope_S scope_T;
91 struct scope_S {
92     scope_T	*se_outer;	    // scope containing this one
93     scopetype_T se_type;
94     int		se_local_count;	    // ctx_locals.ga_len before scope
95     skip_T	se_skip_save;	    // ctx_skip before the block
96     union {
97 	ifscope_T	se_if;
98 	whilescope_T	se_while;
99 	forscope_T	se_for;
100 	tryscope_T	se_try;
101     } se_u;
102 };
103 
104 /*
105  * Entry for "ctx_locals".  Used for arguments and local variables.
106  */
107 typedef struct {
108     char_u	*lv_name;
109     type_T	*lv_type;
110     int		lv_idx;		// index of the variable on the stack
111     int		lv_from_outer;	// when TRUE using ctx_outer scope
112     int		lv_const;	// when TRUE cannot be assigned to
113     int		lv_arg;		// when TRUE this is an argument
114 } lvar_T;
115 
116 /*
117  * Context for compiling lines of Vim script.
118  * Stores info about the local variables and condition stack.
119  */
120 struct cctx_S {
121     ufunc_T	*ctx_ufunc;	    // current function
122     int		ctx_lnum;	    // line number in current function
123     char_u	*ctx_line_start;    // start of current line or NULL
124     garray_T	ctx_instr;	    // generated instructions
125 
126     garray_T	ctx_locals;	    // currently visible local variables
127     int		ctx_locals_count;   // total number of local variables
128 
129     int		ctx_closure_count;  // number of closures created in the
130 				    // function
131 
132     garray_T	ctx_imports;	    // imported items
133 
134     skip_T	ctx_skip;
135     scope_T	*ctx_scope;	    // current scope, NULL at toplevel
136     int		ctx_had_return;	    // last seen statement was "return"
137 
138     cctx_T	*ctx_outer;	    // outer scope for lambda or nested
139 				    // function
140     int		ctx_outer_used;	    // var in ctx_outer was used
141 
142     garray_T	ctx_type_stack;	    // type of each item on the stack
143     garray_T	*ctx_type_list;	    // list of pointers to allocated types
144 };
145 
146 static void delete_def_function_contents(dfunc_T *dfunc);
147 
148 /*
149  * Lookup variable "name" in the local scope and return it.
150  * Return NULL if not found.
151  */
152     static lvar_T *
153 lookup_local(char_u *name, size_t len, cctx_T *cctx)
154 {
155     int	    idx;
156     lvar_T  *lvar;
157 
158     if (len == 0)
159 	return NULL;
160 
161     // Find local in current function scope.
162     for (idx = 0; idx < cctx->ctx_locals.ga_len; ++idx)
163     {
164 	lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + idx;
165 	if (STRNCMP(name, lvar->lv_name, len) == 0
166 					       && STRLEN(lvar->lv_name) == len)
167 	{
168 	    lvar->lv_from_outer = FALSE;
169 	    return lvar;
170 	}
171     }
172 
173     // Find local in outer function scope.
174     if (cctx->ctx_outer != NULL)
175     {
176 	lvar = lookup_local(name, len, cctx->ctx_outer);
177 	if (lvar != NULL)
178 	{
179 	    // TODO: are there situations we should not mark the outer scope as
180 	    // used?
181 	    cctx->ctx_outer_used = TRUE;
182 	    lvar->lv_from_outer = TRUE;
183 	    return lvar;
184 	}
185     }
186 
187     return NULL;
188 }
189 
190 /*
191  * Lookup an argument in the current function and an enclosing function.
192  * Returns the argument index in "idxp"
193  * Returns the argument type in "type"
194  * Sets "gen_load_outer" to TRUE if found in outer scope.
195  * Returns OK when found, FAIL otherwise.
196  */
197     static int
198 lookup_arg(
199 	char_u	*name,
200 	size_t	len,
201 	int	*idxp,
202 	type_T	**type,
203 	int	*gen_load_outer,
204 	cctx_T	*cctx)
205 {
206     int	    idx;
207     char_u  *va_name;
208 
209     if (len == 0)
210 	return FAIL;
211     for (idx = 0; idx < cctx->ctx_ufunc->uf_args.ga_len; ++idx)
212     {
213 	char_u *arg = FUNCARG(cctx->ctx_ufunc, idx);
214 
215 	if (STRNCMP(name, arg, len) == 0 && arg[len] == NUL)
216 	{
217 	    if (idxp != NULL)
218 	    {
219 		// Arguments are located above the frame pointer.  One further
220 		// if there is a vararg argument
221 		*idxp = idx - (cctx->ctx_ufunc->uf_args.ga_len
222 							    + STACK_FRAME_SIZE)
223 			      + (cctx->ctx_ufunc->uf_va_name != NULL ? -1 : 0);
224 
225 		if (cctx->ctx_ufunc->uf_arg_types != NULL)
226 		    *type = cctx->ctx_ufunc->uf_arg_types[idx];
227 		else
228 		    *type = &t_any;
229 	    }
230 	    return OK;
231 	}
232     }
233 
234     va_name = cctx->ctx_ufunc->uf_va_name;
235     if (va_name != NULL
236 		    && STRNCMP(name, va_name, len) == 0 && va_name[len] == NUL)
237     {
238 	if (idxp != NULL)
239 	{
240 	    // varargs is always the last argument
241 	    *idxp = -STACK_FRAME_SIZE - 1;
242 	    *type = cctx->ctx_ufunc->uf_va_type;
243 	}
244 	return OK;
245     }
246 
247     if (cctx->ctx_outer != NULL)
248     {
249 	// Lookup the name for an argument of the outer function.
250 	if (lookup_arg(name, len, idxp, type, gen_load_outer, cctx->ctx_outer)
251 									 == OK)
252 	{
253 	    *gen_load_outer = TRUE;
254 	    return OK;
255 	}
256     }
257 
258     return FAIL;
259 }
260 
261 /*
262  * Returnd TRUE if the script context is Vim9 script.
263  */
264     static int
265 script_is_vim9()
266 {
267     return SCRIPT_ITEM(current_sctx.sc_sid)->sn_version == SCRIPT_VERSION_VIM9;
268 }
269 
270 /*
271  * Lookup a variable in the current script.
272  * If "vim9script" is TRUE the script must be Vim9 script.  Used for "var"
273  * without "s:".
274  * Returns OK or FAIL.
275  */
276     static int
277 lookup_script(char_u *name, size_t len, int vim9script)
278 {
279     int		    cc;
280     hashtab_T	    *ht = &SCRIPT_VARS(current_sctx.sc_sid);
281     dictitem_T	    *di;
282 
283     if (vim9script && !script_is_vim9())
284 	return FAIL;
285     cc = name[len];
286     name[len] = NUL;
287     di = find_var_in_ht(ht, 0, name, TRUE);
288     name[len] = cc;
289     return di == NULL ? FAIL: OK;
290 }
291 
292 /*
293  * Check if "p[len]" is already defined, either in script "import_sid" or in
294  * compilation context "cctx".
295  * Return FAIL and give an error if it defined.
296  */
297     int
298 check_defined(char_u *p, size_t len, cctx_T *cctx)
299 {
300     int c = p[len];
301 
302     p[len] = NUL;
303     if (lookup_script(p, len, FALSE) == OK
304 	    || (cctx != NULL
305 		&& (lookup_local(p, len, cctx) != NULL
306 		    || lookup_arg(p, len, NULL, NULL, NULL, cctx) == OK))
307 	    || find_imported(p, len, cctx) != NULL
308 	    || find_func_even_dead(p, FALSE, cctx) != NULL)
309     {
310 	p[len] = c;
311 	semsg(_(e_name_already_defined_str), p);
312 	return FAIL;
313     }
314     p[len] = c;
315     return OK;
316 }
317 
318 
319 /////////////////////////////////////////////////////////////////////
320 // Following generate_ functions expect the caller to call ga_grow().
321 
322 #define RETURN_NULL_IF_SKIP(cctx) if (cctx->ctx_skip == SKIP_YES) return NULL
323 #define RETURN_OK_IF_SKIP(cctx) if (cctx->ctx_skip == SKIP_YES) return OK
324 
325 /*
326  * Generate an instruction without arguments.
327  * Returns a pointer to the new instruction, NULL if failed.
328  */
329     static isn_T *
330 generate_instr(cctx_T *cctx, isntype_T isn_type)
331 {
332     garray_T	*instr = &cctx->ctx_instr;
333     isn_T	*isn;
334 
335     RETURN_NULL_IF_SKIP(cctx);
336     if (ga_grow(instr, 1) == FAIL)
337 	return NULL;
338     isn = ((isn_T *)instr->ga_data) + instr->ga_len;
339     isn->isn_type = isn_type;
340     isn->isn_lnum = cctx->ctx_lnum + 1;
341     ++instr->ga_len;
342 
343     return isn;
344 }
345 
346 /*
347  * Generate an instruction without arguments.
348  * "drop" will be removed from the stack.
349  * Returns a pointer to the new instruction, NULL if failed.
350  */
351     static isn_T *
352 generate_instr_drop(cctx_T *cctx, isntype_T isn_type, int drop)
353 {
354     garray_T	*stack = &cctx->ctx_type_stack;
355 
356     RETURN_NULL_IF_SKIP(cctx);
357     stack->ga_len -= drop;
358     return generate_instr(cctx, isn_type);
359 }
360 
361 /*
362  * Generate instruction "isn_type" and put "type" on the type stack.
363  */
364     static isn_T *
365 generate_instr_type(cctx_T *cctx, isntype_T isn_type, type_T *type)
366 {
367     isn_T	*isn;
368     garray_T	*stack = &cctx->ctx_type_stack;
369 
370     if ((isn = generate_instr(cctx, isn_type)) == NULL)
371 	return NULL;
372 
373     if (ga_grow(stack, 1) == FAIL)
374 	return NULL;
375     ((type_T **)stack->ga_data)[stack->ga_len] = type == NULL ? &t_any : type;
376     ++stack->ga_len;
377 
378     return isn;
379 }
380 
381 /*
382  * If type at "offset" isn't already VAR_STRING then generate ISN_2STRING.
383  * But only for simple types.
384  */
385     static int
386 may_generate_2STRING(int offset, cctx_T *cctx)
387 {
388     isn_T	*isn;
389     isntype_T	isntype = ISN_2STRING;
390     garray_T	*stack = &cctx->ctx_type_stack;
391     type_T	**type = ((type_T **)stack->ga_data) + stack->ga_len + offset;
392 
393     switch ((*type)->tt_type)
394     {
395 	// nothing to be done
396 	case VAR_STRING: return OK;
397 
398 	// conversion possible
399 	case VAR_SPECIAL:
400 	case VAR_BOOL:
401 	case VAR_NUMBER:
402 	case VAR_FLOAT:
403 			 break;
404 
405 	// conversion possible (with runtime check)
406 	case VAR_ANY:
407 	case VAR_UNKNOWN:
408 			 isntype = ISN_2STRING_ANY;
409 			 break;
410 
411 	// conversion not possible
412 	case VAR_VOID:
413 	case VAR_BLOB:
414 	case VAR_FUNC:
415 	case VAR_PARTIAL:
416 	case VAR_LIST:
417 	case VAR_DICT:
418 	case VAR_JOB:
419 	case VAR_CHANNEL:
420 			 to_string_error((*type)->tt_type);
421 			 return FAIL;
422     }
423 
424     *type = &t_string;
425     if ((isn = generate_instr(cctx, isntype)) == NULL)
426 	return FAIL;
427     isn->isn_arg.number = offset;
428 
429     return OK;
430 }
431 
432     static int
433 check_number_or_float(vartype_T type1, vartype_T type2, char_u *op)
434 {
435     if (!((type1 == VAR_NUMBER || type1 == VAR_FLOAT || type1 == VAR_ANY)
436 	    && (type2 == VAR_NUMBER || type2 == VAR_FLOAT
437 							 || type2 == VAR_ANY)))
438     {
439 	if (*op == '+')
440 	    emsg(_(e_wrong_argument_type_for_plus));
441 	else
442 	    semsg(_(e_char_requires_number_or_float_arguments), *op);
443 	return FAIL;
444     }
445     return OK;
446 }
447 
448     static int
449 generate_add_instr(
450 	cctx_T *cctx,
451 	vartype_T vartype,
452 	type_T *type1,
453 	type_T *type2)
454 {
455     isn_T *isn = generate_instr_drop(cctx,
456 	      vartype == VAR_NUMBER ? ISN_OPNR
457 	    : vartype == VAR_LIST ? ISN_ADDLIST
458 	    : vartype == VAR_BLOB ? ISN_ADDBLOB
459 #ifdef FEAT_FLOAT
460 	    : vartype == VAR_FLOAT ? ISN_OPFLOAT
461 #endif
462 	    : ISN_OPANY, 1);
463 
464     if (vartype != VAR_LIST && vartype != VAR_BLOB
465 	    && type1->tt_type != VAR_ANY
466 	    && type2->tt_type != VAR_ANY
467 	    && check_number_or_float(
468 			type1->tt_type, type2->tt_type, (char_u *)"+") == FAIL)
469 	return FAIL;
470 
471     if (isn != NULL)
472 	isn->isn_arg.op.op_type = EXPR_ADD;
473     return isn == NULL ? FAIL : OK;
474 }
475 
476 /*
477  * Get the type to use for an instruction for an operation on "type1" and
478  * "type2".  If they are matching use a type-specific instruction. Otherwise
479  * fall back to runtime type checking.
480  */
481     static vartype_T
482 operator_type(type_T *type1, type_T *type2)
483 {
484     if (type1->tt_type == type2->tt_type
485 	    && (type1->tt_type == VAR_NUMBER
486 		|| type1->tt_type == VAR_LIST
487 #ifdef FEAT_FLOAT
488 		|| type1->tt_type == VAR_FLOAT
489 #endif
490 		|| type1->tt_type == VAR_BLOB))
491 	return type1->tt_type;
492     return VAR_ANY;
493 }
494 
495 /*
496  * Generate an instruction with two arguments.  The instruction depends on the
497  * type of the arguments.
498  */
499     static int
500 generate_two_op(cctx_T *cctx, char_u *op)
501 {
502     garray_T	*stack = &cctx->ctx_type_stack;
503     type_T	*type1;
504     type_T	*type2;
505     vartype_T	vartype;
506     isn_T	*isn;
507 
508     RETURN_OK_IF_SKIP(cctx);
509 
510     // Get the known type of the two items on the stack.
511     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2];
512     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1];
513     vartype = operator_type(type1, type2);
514 
515     switch (*op)
516     {
517 	case '+':
518 		  if (generate_add_instr(cctx, vartype, type1, type2) == FAIL)
519 		      return FAIL;
520 		  break;
521 
522 	case '-':
523 	case '*':
524 	case '/': if (check_number_or_float(type1->tt_type, type2->tt_type,
525 								   op) == FAIL)
526 		      return FAIL;
527 		  if (vartype == VAR_NUMBER)
528 		      isn = generate_instr_drop(cctx, ISN_OPNR, 1);
529 #ifdef FEAT_FLOAT
530 		  else if (vartype == VAR_FLOAT)
531 		      isn = generate_instr_drop(cctx, ISN_OPFLOAT, 1);
532 #endif
533 		  else
534 		      isn = generate_instr_drop(cctx, ISN_OPANY, 1);
535 		  if (isn != NULL)
536 		      isn->isn_arg.op.op_type = *op == '*'
537 				 ? EXPR_MULT : *op == '/'? EXPR_DIV : EXPR_SUB;
538 		  break;
539 
540 	case '%': if ((type1->tt_type != VAR_ANY
541 					       && type1->tt_type != VAR_NUMBER)
542 			  || (type2->tt_type != VAR_ANY
543 					      && type2->tt_type != VAR_NUMBER))
544 		  {
545 		      emsg(_(e_percent_requires_number_arguments));
546 		      return FAIL;
547 		  }
548 		  isn = generate_instr_drop(cctx,
549 			      vartype == VAR_NUMBER ? ISN_OPNR : ISN_OPANY, 1);
550 		  if (isn != NULL)
551 		      isn->isn_arg.op.op_type = EXPR_REM;
552 		  break;
553     }
554 
555     // correct type of result
556     if (vartype == VAR_ANY)
557     {
558 	type_T *type = &t_any;
559 
560 #ifdef FEAT_FLOAT
561 	// float+number and number+float results in float
562 	if ((type1->tt_type == VAR_NUMBER || type1->tt_type == VAR_FLOAT)
563 		&& (type2->tt_type == VAR_NUMBER || type2->tt_type == VAR_FLOAT))
564 	    type = &t_float;
565 #endif
566 	((type_T **)stack->ga_data)[stack->ga_len - 1] = type;
567     }
568 
569     return OK;
570 }
571 
572 /*
573  * Get the instruction to use for comparing "type1" with "type2"
574  * Return ISN_DROP when failed.
575  */
576     static isntype_T
577 get_compare_isn(exptype_T exptype, vartype_T type1, vartype_T type2)
578 {
579     isntype_T	isntype = ISN_DROP;
580 
581     if (type1 == VAR_UNKNOWN)
582 	type1 = VAR_ANY;
583     if (type2 == VAR_UNKNOWN)
584 	type2 = VAR_ANY;
585 
586     if (type1 == type2)
587     {
588 	switch (type1)
589 	{
590 	    case VAR_BOOL: isntype = ISN_COMPAREBOOL; break;
591 	    case VAR_SPECIAL: isntype = ISN_COMPARESPECIAL; break;
592 	    case VAR_NUMBER: isntype = ISN_COMPARENR; break;
593 	    case VAR_FLOAT: isntype = ISN_COMPAREFLOAT; break;
594 	    case VAR_STRING: isntype = ISN_COMPARESTRING; break;
595 	    case VAR_BLOB: isntype = ISN_COMPAREBLOB; break;
596 	    case VAR_LIST: isntype = ISN_COMPARELIST; break;
597 	    case VAR_DICT: isntype = ISN_COMPAREDICT; break;
598 	    case VAR_FUNC: isntype = ISN_COMPAREFUNC; break;
599 	    default: isntype = ISN_COMPAREANY; break;
600 	}
601     }
602     else if (type1 == VAR_ANY || type2 == VAR_ANY
603 	    || ((type1 == VAR_NUMBER || type1 == VAR_FLOAT)
604 	      && (type2 == VAR_NUMBER || type2 ==VAR_FLOAT)))
605 	isntype = ISN_COMPAREANY;
606 
607     if ((exptype == EXPR_IS || exptype == EXPR_ISNOT)
608 	    && (isntype == ISN_COMPAREBOOL
609 	    || isntype == ISN_COMPARESPECIAL
610 	    || isntype == ISN_COMPARENR
611 	    || isntype == ISN_COMPAREFLOAT))
612     {
613 	semsg(_(e_cannot_use_str_with_str),
614 		exptype == EXPR_IS ? "is" : "isnot" , vartype_name(type1));
615 	return ISN_DROP;
616     }
617     if (isntype == ISN_DROP
618 	    || ((exptype != EXPR_EQUAL && exptype != EXPR_NEQUAL
619 		    && (type1 == VAR_BOOL || type1 == VAR_SPECIAL
620 		       || type2 == VAR_BOOL || type2 == VAR_SPECIAL)))
621 	    || ((exptype != EXPR_EQUAL && exptype != EXPR_NEQUAL
622 				 && exptype != EXPR_IS && exptype != EXPR_ISNOT
623 		    && (type1 == VAR_BLOB || type2 == VAR_BLOB
624 			|| type1 == VAR_LIST || type2 == VAR_LIST))))
625     {
626 	semsg(_(e_cannot_compare_str_with_str),
627 		vartype_name(type1), vartype_name(type2));
628 	return ISN_DROP;
629     }
630     return isntype;
631 }
632 
633     int
634 check_compare_types(exptype_T type, typval_T *tv1, typval_T *tv2)
635 {
636     if (get_compare_isn(type, tv1->v_type, tv2->v_type) == ISN_DROP)
637 	return FAIL;
638     return OK;
639 }
640 
641 /*
642  * Generate an ISN_COMPARE* instruction with a boolean result.
643  */
644     static int
645 generate_COMPARE(cctx_T *cctx, exptype_T exptype, int ic)
646 {
647     isntype_T	isntype;
648     isn_T	*isn;
649     garray_T	*stack = &cctx->ctx_type_stack;
650     vartype_T	type1;
651     vartype_T	type2;
652 
653     RETURN_OK_IF_SKIP(cctx);
654 
655     // Get the known type of the two items on the stack.  If they are matching
656     // use a type-specific instruction. Otherwise fall back to runtime type
657     // checking.
658     type1 = ((type_T **)stack->ga_data)[stack->ga_len - 2]->tt_type;
659     type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1]->tt_type;
660     isntype = get_compare_isn(exptype, type1, type2);
661     if (isntype == ISN_DROP)
662 	return FAIL;
663 
664     if ((isn = generate_instr(cctx, isntype)) == NULL)
665 	return FAIL;
666     isn->isn_arg.op.op_type = exptype;
667     isn->isn_arg.op.op_ic = ic;
668 
669     // takes two arguments, puts one bool back
670     if (stack->ga_len >= 2)
671     {
672 	--stack->ga_len;
673 	((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_bool;
674     }
675 
676     return OK;
677 }
678 
679 /*
680  * Generate an ISN_2BOOL instruction.
681  */
682     static int
683 generate_2BOOL(cctx_T *cctx, int invert)
684 {
685     isn_T	*isn;
686     garray_T	*stack = &cctx->ctx_type_stack;
687 
688     RETURN_OK_IF_SKIP(cctx);
689     if ((isn = generate_instr(cctx, ISN_2BOOL)) == NULL)
690 	return FAIL;
691     isn->isn_arg.number = invert;
692 
693     // type becomes bool
694     ((type_T **)stack->ga_data)[stack->ga_len - 1] = &t_bool;
695 
696     return OK;
697 }
698 
699     static int
700 generate_TYPECHECK(cctx_T *cctx, type_T *vartype, int offset)
701 {
702     isn_T	*isn;
703     garray_T	*stack = &cctx->ctx_type_stack;
704 
705     RETURN_OK_IF_SKIP(cctx);
706     if ((isn = generate_instr(cctx, ISN_CHECKTYPE)) == NULL)
707 	return FAIL;
708     // TODO: whole type, e.g. for a function also arg and return types
709     isn->isn_arg.type.ct_type = vartype->tt_type;
710     isn->isn_arg.type.ct_off = offset;
711 
712     // type becomes vartype
713     ((type_T **)stack->ga_data)[stack->ga_len + offset] = vartype;
714 
715     return OK;
716 }
717 
718 /*
719  * Check that
720  * - "actual" is "expected" type or
721  * - "actual" is a type that can be "expected" type: add a runtime check; or
722  * - return FAIL.
723  */
724     static int
725 need_type(
726 	type_T	*actual,
727 	type_T	*expected,
728 	int	offset,
729 	cctx_T	*cctx,
730 	int	silent)
731 {
732     if (check_type(expected, actual, FALSE, 0) == OK)
733 	return OK;
734     if (actual->tt_type != VAR_ANY
735 	    && actual->tt_type != VAR_UNKNOWN
736 	    && !(actual->tt_type == VAR_FUNC
737 		&& (actual->tt_member == &t_any || actual->tt_argcount < 0)))
738     {
739 	if (!silent)
740 	    type_mismatch(expected, actual);
741 	return FAIL;
742     }
743     generate_TYPECHECK(cctx, expected, offset);
744     return OK;
745 }
746 
747 /*
748  * Generate an ISN_PUSHNR instruction.
749  */
750     static int
751 generate_PUSHNR(cctx_T *cctx, varnumber_T number)
752 {
753     isn_T	*isn;
754 
755     RETURN_OK_IF_SKIP(cctx);
756     if ((isn = generate_instr_type(cctx, ISN_PUSHNR, &t_number)) == NULL)
757 	return FAIL;
758     isn->isn_arg.number = number;
759 
760     return OK;
761 }
762 
763 /*
764  * Generate an ISN_PUSHBOOL instruction.
765  */
766     static int
767 generate_PUSHBOOL(cctx_T *cctx, varnumber_T number)
768 {
769     isn_T	*isn;
770 
771     RETURN_OK_IF_SKIP(cctx);
772     if ((isn = generate_instr_type(cctx, ISN_PUSHBOOL, &t_bool)) == NULL)
773 	return FAIL;
774     isn->isn_arg.number = number;
775 
776     return OK;
777 }
778 
779 /*
780  * Generate an ISN_PUSHSPEC instruction.
781  */
782     static int
783 generate_PUSHSPEC(cctx_T *cctx, varnumber_T number)
784 {
785     isn_T	*isn;
786 
787     RETURN_OK_IF_SKIP(cctx);
788     if ((isn = generate_instr_type(cctx, ISN_PUSHSPEC, &t_special)) == NULL)
789 	return FAIL;
790     isn->isn_arg.number = number;
791 
792     return OK;
793 }
794 
795 #ifdef FEAT_FLOAT
796 /*
797  * Generate an ISN_PUSHF instruction.
798  */
799     static int
800 generate_PUSHF(cctx_T *cctx, float_T fnumber)
801 {
802     isn_T	*isn;
803 
804     RETURN_OK_IF_SKIP(cctx);
805     if ((isn = generate_instr_type(cctx, ISN_PUSHF, &t_float)) == NULL)
806 	return FAIL;
807     isn->isn_arg.fnumber = fnumber;
808 
809     return OK;
810 }
811 #endif
812 
813 /*
814  * Generate an ISN_PUSHS instruction.
815  * Consumes "str".
816  */
817     static int
818 generate_PUSHS(cctx_T *cctx, char_u *str)
819 {
820     isn_T	*isn;
821 
822     RETURN_OK_IF_SKIP(cctx);
823     if ((isn = generate_instr_type(cctx, ISN_PUSHS, &t_string)) == NULL)
824 	return FAIL;
825     isn->isn_arg.string = str;
826 
827     return OK;
828 }
829 
830 /*
831  * Generate an ISN_PUSHCHANNEL instruction.
832  * Consumes "channel".
833  */
834     static int
835 generate_PUSHCHANNEL(cctx_T *cctx, channel_T *channel)
836 {
837     isn_T	*isn;
838 
839     RETURN_OK_IF_SKIP(cctx);
840     if ((isn = generate_instr_type(cctx, ISN_PUSHCHANNEL, &t_channel)) == NULL)
841 	return FAIL;
842     isn->isn_arg.channel = channel;
843 
844     return OK;
845 }
846 
847 /*
848  * Generate an ISN_PUSHJOB instruction.
849  * Consumes "job".
850  */
851     static int
852 generate_PUSHJOB(cctx_T *cctx, job_T *job)
853 {
854     isn_T	*isn;
855 
856     RETURN_OK_IF_SKIP(cctx);
857     if ((isn = generate_instr_type(cctx, ISN_PUSHJOB, &t_channel)) == NULL)
858 	return FAIL;
859     isn->isn_arg.job = job;
860 
861     return OK;
862 }
863 
864 /*
865  * Generate an ISN_PUSHBLOB instruction.
866  * Consumes "blob".
867  */
868     static int
869 generate_PUSHBLOB(cctx_T *cctx, blob_T *blob)
870 {
871     isn_T	*isn;
872 
873     RETURN_OK_IF_SKIP(cctx);
874     if ((isn = generate_instr_type(cctx, ISN_PUSHBLOB, &t_blob)) == NULL)
875 	return FAIL;
876     isn->isn_arg.blob = blob;
877 
878     return OK;
879 }
880 
881 /*
882  * Generate an ISN_PUSHFUNC instruction with name "name".
883  * Consumes "name".
884  */
885     static int
886 generate_PUSHFUNC(cctx_T *cctx, char_u *name, type_T *type)
887 {
888     isn_T	*isn;
889 
890     RETURN_OK_IF_SKIP(cctx);
891     if ((isn = generate_instr_type(cctx, ISN_PUSHFUNC, type)) == NULL)
892 	return FAIL;
893     isn->isn_arg.string = name == NULL ? NULL : vim_strsave(name);
894 
895     return OK;
896 }
897 
898 /*
899  * Generate an ISN_GETITEM instruction with "index".
900  */
901     static int
902 generate_GETITEM(cctx_T *cctx, int index)
903 {
904     isn_T	*isn;
905     garray_T	*stack = &cctx->ctx_type_stack;
906     type_T	*type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
907     type_T	*item_type = &t_any;
908 
909     RETURN_OK_IF_SKIP(cctx);
910 
911     if (type->tt_type != VAR_LIST)
912     {
913 	// cannot happen, caller has checked the type
914 	emsg(_(e_listreq));
915 	return FAIL;
916     }
917     item_type = type->tt_member;
918     if ((isn = generate_instr(cctx, ISN_GETITEM)) == NULL)
919 	return FAIL;
920     isn->isn_arg.number = index;
921 
922     // add the item type to the type stack
923     if (ga_grow(stack, 1) == FAIL)
924 	return FAIL;
925     ((type_T **)stack->ga_data)[stack->ga_len] = item_type;
926     ++stack->ga_len;
927     return OK;
928 }
929 
930 /*
931  * Generate an ISN_SLICE instruction with "count".
932  */
933     static int
934 generate_SLICE(cctx_T *cctx, int count)
935 {
936     isn_T	*isn;
937 
938     RETURN_OK_IF_SKIP(cctx);
939     if ((isn = generate_instr(cctx, ISN_SLICE)) == NULL)
940 	return FAIL;
941     isn->isn_arg.number = count;
942     return OK;
943 }
944 
945 /*
946  * Generate an ISN_CHECKLEN instruction with "min_len".
947  */
948     static int
949 generate_CHECKLEN(cctx_T *cctx, int min_len, int more_OK)
950 {
951     isn_T	*isn;
952 
953     RETURN_OK_IF_SKIP(cctx);
954 
955     if ((isn = generate_instr(cctx, ISN_CHECKLEN)) == NULL)
956 	return FAIL;
957     isn->isn_arg.checklen.cl_min_len = min_len;
958     isn->isn_arg.checklen.cl_more_OK = more_OK;
959 
960     return OK;
961 }
962 
963 /*
964  * Generate an ISN_STORE instruction.
965  */
966     static int
967 generate_STORE(cctx_T *cctx, isntype_T isn_type, int idx, char_u *name)
968 {
969     isn_T	*isn;
970 
971     RETURN_OK_IF_SKIP(cctx);
972     if ((isn = generate_instr_drop(cctx, isn_type, 1)) == NULL)
973 	return FAIL;
974     if (name != NULL)
975 	isn->isn_arg.string = vim_strsave(name);
976     else
977 	isn->isn_arg.number = idx;
978 
979     return OK;
980 }
981 
982 /*
983  * Generate an ISN_STORENR instruction (short for ISN_PUSHNR + ISN_STORE)
984  */
985     static int
986 generate_STORENR(cctx_T *cctx, int idx, varnumber_T value)
987 {
988     isn_T	*isn;
989 
990     RETURN_OK_IF_SKIP(cctx);
991     if ((isn = generate_instr(cctx, ISN_STORENR)) == NULL)
992 	return FAIL;
993     isn->isn_arg.storenr.stnr_idx = idx;
994     isn->isn_arg.storenr.stnr_val = value;
995 
996     return OK;
997 }
998 
999 /*
1000  * Generate an ISN_STOREOPT instruction
1001  */
1002     static int
1003 generate_STOREOPT(cctx_T *cctx, char_u *name, int opt_flags)
1004 {
1005     isn_T	*isn;
1006 
1007     RETURN_OK_IF_SKIP(cctx);
1008     if ((isn = generate_instr_drop(cctx, ISN_STOREOPT, 1)) == NULL)
1009 	return FAIL;
1010     isn->isn_arg.storeopt.so_name = vim_strsave(name);
1011     isn->isn_arg.storeopt.so_flags = opt_flags;
1012 
1013     return OK;
1014 }
1015 
1016 /*
1017  * Generate an ISN_LOAD or similar instruction.
1018  */
1019     static int
1020 generate_LOAD(
1021 	cctx_T	    *cctx,
1022 	isntype_T   isn_type,
1023 	int	    idx,
1024 	char_u	    *name,
1025 	type_T	    *type)
1026 {
1027     isn_T	*isn;
1028 
1029     RETURN_OK_IF_SKIP(cctx);
1030     if ((isn = generate_instr_type(cctx, isn_type, type)) == NULL)
1031 	return FAIL;
1032     if (name != NULL)
1033 	isn->isn_arg.string = vim_strsave(name);
1034     else
1035 	isn->isn_arg.number = idx;
1036 
1037     return OK;
1038 }
1039 
1040 /*
1041  * Generate an ISN_LOADV instruction for v:var.
1042  */
1043     static int
1044 generate_LOADV(
1045 	cctx_T	    *cctx,
1046 	char_u	    *name,
1047 	int	    error)
1048 {
1049     int	    di_flags;
1050     int	    vidx = find_vim_var(name, &di_flags);
1051     type_T  *type;
1052 
1053     RETURN_OK_IF_SKIP(cctx);
1054     if (vidx < 0)
1055     {
1056 	if (error)
1057 	    semsg(_(e_variable_not_found_str), name);
1058 	return FAIL;
1059     }
1060     type = typval2type_vimvar(get_vim_var_tv(vidx), cctx->ctx_type_list);
1061 
1062     return generate_LOAD(cctx, ISN_LOADV, vidx, NULL, type);
1063 }
1064 
1065 /*
1066  * Generate an ISN_UNLET instruction.
1067  */
1068     static int
1069 generate_UNLET(cctx_T *cctx, isntype_T isn_type, char_u *name, int forceit)
1070 {
1071     isn_T	*isn;
1072 
1073     RETURN_OK_IF_SKIP(cctx);
1074     if ((isn = generate_instr(cctx, isn_type)) == NULL)
1075 	return FAIL;
1076     isn->isn_arg.unlet.ul_name = vim_strsave(name);
1077     isn->isn_arg.unlet.ul_forceit = forceit;
1078 
1079     return OK;
1080 }
1081 
1082 /*
1083  * Generate an ISN_LOADS instruction.
1084  */
1085     static int
1086 generate_OLDSCRIPT(
1087 	cctx_T	    *cctx,
1088 	isntype_T   isn_type,
1089 	char_u	    *name,
1090 	int	    sid,
1091 	type_T	    *type)
1092 {
1093     isn_T	*isn;
1094 
1095     RETURN_OK_IF_SKIP(cctx);
1096     if (isn_type == ISN_LOADS)
1097 	isn = generate_instr_type(cctx, isn_type, type);
1098     else
1099 	isn = generate_instr_drop(cctx, isn_type, 1);
1100     if (isn == NULL)
1101 	return FAIL;
1102     isn->isn_arg.loadstore.ls_name = vim_strsave(name);
1103     isn->isn_arg.loadstore.ls_sid = sid;
1104 
1105     return OK;
1106 }
1107 
1108 /*
1109  * Generate an ISN_LOADSCRIPT or ISN_STORESCRIPT instruction.
1110  */
1111     static int
1112 generate_VIM9SCRIPT(
1113 	cctx_T	    *cctx,
1114 	isntype_T   isn_type,
1115 	int	    sid,
1116 	int	    idx,
1117 	type_T	    *type)
1118 {
1119     isn_T	*isn;
1120 
1121     RETURN_OK_IF_SKIP(cctx);
1122     if (isn_type == ISN_LOADSCRIPT)
1123 	isn = generate_instr_type(cctx, isn_type, type);
1124     else
1125 	isn = generate_instr_drop(cctx, isn_type, 1);
1126     if (isn == NULL)
1127 	return FAIL;
1128     isn->isn_arg.script.script_sid = sid;
1129     isn->isn_arg.script.script_idx = idx;
1130     return OK;
1131 }
1132 
1133 /*
1134  * Generate an ISN_NEWLIST instruction.
1135  */
1136     static int
1137 generate_NEWLIST(cctx_T *cctx, int count)
1138 {
1139     isn_T	*isn;
1140     garray_T	*stack = &cctx->ctx_type_stack;
1141     type_T	*type;
1142     type_T	*member;
1143 
1144     RETURN_OK_IF_SKIP(cctx);
1145     if ((isn = generate_instr(cctx, ISN_NEWLIST)) == NULL)
1146 	return FAIL;
1147     isn->isn_arg.number = count;
1148 
1149     // get the member type from all the items on the stack.
1150     if (count == 0)
1151 	member = &t_void;
1152     else
1153 	member = get_member_type_from_stack(
1154 	    ((type_T **)stack->ga_data) + stack->ga_len, count, 1,
1155 							  cctx->ctx_type_list);
1156     type = get_list_type(member, cctx->ctx_type_list);
1157 
1158     // drop the value types
1159     stack->ga_len -= count;
1160 
1161     // add the list type to the type stack
1162     if (ga_grow(stack, 1) == FAIL)
1163 	return FAIL;
1164     ((type_T **)stack->ga_data)[stack->ga_len] = type;
1165     ++stack->ga_len;
1166 
1167     return OK;
1168 }
1169 
1170 /*
1171  * Generate an ISN_NEWDICT instruction.
1172  */
1173     static int
1174 generate_NEWDICT(cctx_T *cctx, int count)
1175 {
1176     isn_T	*isn;
1177     garray_T	*stack = &cctx->ctx_type_stack;
1178     type_T	*type;
1179     type_T	*member;
1180 
1181     RETURN_OK_IF_SKIP(cctx);
1182     if ((isn = generate_instr(cctx, ISN_NEWDICT)) == NULL)
1183 	return FAIL;
1184     isn->isn_arg.number = count;
1185 
1186     if (count == 0)
1187 	member = &t_void;
1188     else
1189 	member = get_member_type_from_stack(
1190 	    ((type_T **)stack->ga_data) + stack->ga_len, count, 2,
1191 							  cctx->ctx_type_list);
1192     type = get_dict_type(member, cctx->ctx_type_list);
1193 
1194     // drop the key and value types
1195     stack->ga_len -= 2 * count;
1196 
1197     // add the dict type to the type stack
1198     if (ga_grow(stack, 1) == FAIL)
1199 	return FAIL;
1200     ((type_T **)stack->ga_data)[stack->ga_len] = type;
1201     ++stack->ga_len;
1202 
1203     return OK;
1204 }
1205 
1206 /*
1207  * Generate an ISN_FUNCREF instruction.
1208  */
1209     static int
1210 generate_FUNCREF(cctx_T *cctx, ufunc_T *ufunc)
1211 {
1212     isn_T	*isn;
1213     garray_T	*stack = &cctx->ctx_type_stack;
1214 
1215     RETURN_OK_IF_SKIP(cctx);
1216     if ((isn = generate_instr(cctx, ISN_FUNCREF)) == NULL)
1217 	return FAIL;
1218     isn->isn_arg.funcref.fr_func = ufunc->uf_dfunc_idx;
1219     isn->isn_arg.funcref.fr_var_idx = cctx->ctx_closure_count++;
1220 
1221     if (ga_grow(stack, 1) == FAIL)
1222 	return FAIL;
1223     ((type_T **)stack->ga_data)[stack->ga_len] =
1224 	       ufunc->uf_func_type == NULL ? &t_func_any : ufunc->uf_func_type;
1225     ++stack->ga_len;
1226 
1227     return OK;
1228 }
1229 
1230 /*
1231  * Generate an ISN_NEWFUNC instruction.
1232  */
1233     static int
1234 generate_NEWFUNC(cctx_T *cctx, char_u *lambda_name, char_u *func_name)
1235 {
1236     isn_T	*isn;
1237     char_u	*name;
1238 
1239     RETURN_OK_IF_SKIP(cctx);
1240     name = vim_strsave(lambda_name);
1241     if (name == NULL)
1242 	return FAIL;
1243     if ((isn = generate_instr(cctx, ISN_NEWFUNC)) == NULL)
1244 	return FAIL;
1245     isn->isn_arg.newfunc.nf_lambda = name;
1246     isn->isn_arg.newfunc.nf_global = func_name;
1247 
1248     return OK;
1249 }
1250 
1251 /*
1252  * Generate an ISN_JUMP instruction.
1253  */
1254     static int
1255 generate_JUMP(cctx_T *cctx, jumpwhen_T when, int where)
1256 {
1257     isn_T	*isn;
1258     garray_T	*stack = &cctx->ctx_type_stack;
1259 
1260     RETURN_OK_IF_SKIP(cctx);
1261     if ((isn = generate_instr(cctx, ISN_JUMP)) == NULL)
1262 	return FAIL;
1263     isn->isn_arg.jump.jump_when = when;
1264     isn->isn_arg.jump.jump_where = where;
1265 
1266     if (when != JUMP_ALWAYS && stack->ga_len > 0)
1267 	--stack->ga_len;
1268 
1269     return OK;
1270 }
1271 
1272     static int
1273 generate_FOR(cctx_T *cctx, int loop_idx)
1274 {
1275     isn_T	*isn;
1276     garray_T	*stack = &cctx->ctx_type_stack;
1277 
1278     RETURN_OK_IF_SKIP(cctx);
1279     if ((isn = generate_instr(cctx, ISN_FOR)) == NULL)
1280 	return FAIL;
1281     isn->isn_arg.forloop.for_idx = loop_idx;
1282 
1283     if (ga_grow(stack, 1) == FAIL)
1284 	return FAIL;
1285     // type doesn't matter, will be stored next
1286     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
1287     ++stack->ga_len;
1288 
1289     return OK;
1290 }
1291 
1292 /*
1293  * Generate an ISN_BCALL instruction.
1294  * "method_call" is TRUE for "value->method()"
1295  * Return FAIL if the number of arguments is wrong.
1296  */
1297     static int
1298 generate_BCALL(cctx_T *cctx, int func_idx, int argcount, int method_call)
1299 {
1300     isn_T	*isn;
1301     garray_T	*stack = &cctx->ctx_type_stack;
1302     int		argoff;
1303     type_T	*argtypes[MAX_FUNC_ARGS];
1304     int		i;
1305 
1306     RETURN_OK_IF_SKIP(cctx);
1307     argoff = check_internal_func(func_idx, argcount);
1308     if (argoff < 0)
1309 	return FAIL;
1310 
1311     if (method_call && argoff > 1)
1312     {
1313 	if ((isn = generate_instr(cctx, ISN_SHUFFLE)) == NULL)
1314 	    return FAIL;
1315 	isn->isn_arg.shuffle.shfl_item = argcount;
1316 	isn->isn_arg.shuffle.shfl_up = argoff - 1;
1317     }
1318 
1319     if ((isn = generate_instr(cctx, ISN_BCALL)) == NULL)
1320 	return FAIL;
1321     isn->isn_arg.bfunc.cbf_idx = func_idx;
1322     isn->isn_arg.bfunc.cbf_argcount = argcount;
1323 
1324     for (i = 0; i < argcount; ++i)
1325 	argtypes[i] = ((type_T **)stack->ga_data)[stack->ga_len - argcount + i];
1326 
1327     stack->ga_len -= argcount; // drop the arguments
1328     if (ga_grow(stack, 1) == FAIL)
1329 	return FAIL;
1330     ((type_T **)stack->ga_data)[stack->ga_len] =
1331 			  internal_func_ret_type(func_idx, argcount, argtypes);
1332     ++stack->ga_len;	    // add return value
1333 
1334     return OK;
1335 }
1336 
1337 /*
1338  * Generate an ISN_DCALL or ISN_UCALL instruction.
1339  * Return FAIL if the number of arguments is wrong.
1340  */
1341     static int
1342 generate_CALL(cctx_T *cctx, ufunc_T *ufunc, int pushed_argcount)
1343 {
1344     isn_T	*isn;
1345     garray_T	*stack = &cctx->ctx_type_stack;
1346     int		regular_args = ufunc->uf_args.ga_len;
1347     int		argcount = pushed_argcount;
1348 
1349     RETURN_OK_IF_SKIP(cctx);
1350     if (argcount > regular_args && !has_varargs(ufunc))
1351     {
1352 	semsg(_(e_toomanyarg), ufunc->uf_name);
1353 	return FAIL;
1354     }
1355     if (argcount < regular_args - ufunc->uf_def_args.ga_len)
1356     {
1357 	semsg(_(e_toofewarg), ufunc->uf_name);
1358 	return FAIL;
1359     }
1360 
1361     if (ufunc->uf_def_status != UF_NOT_COMPILED)
1362     {
1363 	int		i;
1364 
1365 	for (i = 0; i < argcount; ++i)
1366 	{
1367 	    type_T *expected;
1368 	    type_T *actual;
1369 
1370 	    if (i < regular_args)
1371 	    {
1372 		if (ufunc->uf_arg_types == NULL)
1373 		    continue;
1374 		expected = ufunc->uf_arg_types[i];
1375 	    }
1376 	    else if (ufunc->uf_va_type == NULL)
1377 		// possibly a lambda
1378 		expected = &t_any;
1379 	    else
1380 		expected = ufunc->uf_va_type->tt_member;
1381 	    actual = ((type_T **)stack->ga_data)[stack->ga_len - argcount + i];
1382 	    if (need_type(actual, expected, -argcount + i, cctx, TRUE) == FAIL)
1383 	    {
1384 		arg_type_mismatch(expected, actual, i + 1);
1385 		return FAIL;
1386 	    }
1387 	}
1388 	if (ufunc->uf_def_status == UF_TO_BE_COMPILED)
1389 	    if (compile_def_function(ufunc, ufunc->uf_ret_type == NULL, NULL)
1390 								       == FAIL)
1391 		return FAIL;
1392     }
1393 
1394     if ((isn = generate_instr(cctx,
1395 		    ufunc->uf_def_status != UF_NOT_COMPILED ? ISN_DCALL
1396 							 : ISN_UCALL)) == NULL)
1397 	return FAIL;
1398     if (ufunc->uf_def_status != UF_NOT_COMPILED)
1399     {
1400 	isn->isn_arg.dfunc.cdf_idx = ufunc->uf_dfunc_idx;
1401 	isn->isn_arg.dfunc.cdf_argcount = argcount;
1402     }
1403     else
1404     {
1405 	// A user function may be deleted and redefined later, can't use the
1406 	// ufunc pointer, need to look it up again at runtime.
1407 	isn->isn_arg.ufunc.cuf_name = vim_strsave(ufunc->uf_name);
1408 	isn->isn_arg.ufunc.cuf_argcount = argcount;
1409     }
1410 
1411     stack->ga_len -= argcount; // drop the arguments
1412     if (ga_grow(stack, 1) == FAIL)
1413 	return FAIL;
1414     // add return value
1415     ((type_T **)stack->ga_data)[stack->ga_len] = ufunc->uf_ret_type;
1416     ++stack->ga_len;
1417 
1418     return OK;
1419 }
1420 
1421 /*
1422  * Generate an ISN_UCALL instruction when the function isn't defined yet.
1423  */
1424     static int
1425 generate_UCALL(cctx_T *cctx, char_u *name, int argcount)
1426 {
1427     isn_T	*isn;
1428     garray_T	*stack = &cctx->ctx_type_stack;
1429 
1430     RETURN_OK_IF_SKIP(cctx);
1431     if ((isn = generate_instr(cctx, ISN_UCALL)) == NULL)
1432 	return FAIL;
1433     isn->isn_arg.ufunc.cuf_name = vim_strsave(name);
1434     isn->isn_arg.ufunc.cuf_argcount = argcount;
1435 
1436     stack->ga_len -= argcount; // drop the arguments
1437     if (ga_grow(stack, 1) == FAIL)
1438 	return FAIL;
1439     // add return value
1440     ((type_T **)stack->ga_data)[stack->ga_len] = &t_any;
1441     ++stack->ga_len;
1442 
1443     return OK;
1444 }
1445 
1446 /*
1447  * Generate an ISN_PCALL instruction.
1448  * "type" is the type of the FuncRef.
1449  */
1450     static int
1451 generate_PCALL(
1452 	cctx_T	*cctx,
1453 	int	argcount,
1454 	char_u	*name,
1455 	type_T	*type,
1456 	int	at_top)
1457 {
1458     isn_T	*isn;
1459     garray_T	*stack = &cctx->ctx_type_stack;
1460     type_T	*ret_type;
1461 
1462     RETURN_OK_IF_SKIP(cctx);
1463 
1464     if (type->tt_type == VAR_ANY)
1465 	ret_type = &t_any;
1466     else if (type->tt_type == VAR_FUNC || type->tt_type == VAR_PARTIAL)
1467     {
1468 	if (type->tt_argcount != -1)
1469 	{
1470 	    int	    varargs = (type->tt_flags & TTFLAG_VARARGS) ? 1 : 0;
1471 
1472 	    if (argcount < type->tt_min_argcount - varargs)
1473 	    {
1474 		semsg(_(e_toofewarg), "[reference]");
1475 		return FAIL;
1476 	    }
1477 	    if (!varargs && argcount > type->tt_argcount)
1478 	    {
1479 		semsg(_(e_toomanyarg), "[reference]");
1480 		return FAIL;
1481 	    }
1482 	}
1483 	ret_type = type->tt_member;
1484     }
1485     else
1486     {
1487 	semsg(_(e_not_callable_type_str), name);
1488 	return FAIL;
1489     }
1490 
1491     if ((isn = generate_instr(cctx, ISN_PCALL)) == NULL)
1492 	return FAIL;
1493     isn->isn_arg.pfunc.cpf_top = at_top;
1494     isn->isn_arg.pfunc.cpf_argcount = argcount;
1495 
1496     stack->ga_len -= argcount; // drop the arguments
1497 
1498     // drop the funcref/partial, get back the return value
1499     ((type_T **)stack->ga_data)[stack->ga_len - 1] = ret_type;
1500 
1501     // If partial is above the arguments it must be cleared and replaced with
1502     // the return value.
1503     if (at_top && generate_instr(cctx, ISN_PCALL_END) == NULL)
1504 	return FAIL;
1505 
1506     return OK;
1507 }
1508 
1509 /*
1510  * Generate an ISN_STRINGMEMBER instruction.
1511  */
1512     static int
1513 generate_STRINGMEMBER(cctx_T *cctx, char_u *name, size_t len)
1514 {
1515     isn_T	*isn;
1516     garray_T	*stack = &cctx->ctx_type_stack;
1517     type_T	*type;
1518 
1519     RETURN_OK_IF_SKIP(cctx);
1520     if ((isn = generate_instr(cctx, ISN_STRINGMEMBER)) == NULL)
1521 	return FAIL;
1522     isn->isn_arg.string = vim_strnsave(name, len);
1523 
1524     // check for dict type
1525     type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
1526     if (type->tt_type != VAR_DICT && type != &t_any)
1527     {
1528 	emsg(_(e_dictreq));
1529 	return FAIL;
1530     }
1531     // change dict type to dict member type
1532     if (type->tt_type == VAR_DICT)
1533 	((type_T **)stack->ga_data)[stack->ga_len - 1] = type->tt_member;
1534 
1535     return OK;
1536 }
1537 
1538 /*
1539  * Generate an ISN_ECHO instruction.
1540  */
1541     static int
1542 generate_ECHO(cctx_T *cctx, int with_white, int count)
1543 {
1544     isn_T	*isn;
1545 
1546     RETURN_OK_IF_SKIP(cctx);
1547     if ((isn = generate_instr_drop(cctx, ISN_ECHO, count)) == NULL)
1548 	return FAIL;
1549     isn->isn_arg.echo.echo_with_white = with_white;
1550     isn->isn_arg.echo.echo_count = count;
1551 
1552     return OK;
1553 }
1554 
1555 /*
1556  * Generate an ISN_EXECUTE/ISN_ECHOMSG/ISN_ECHOERR instruction.
1557  */
1558     static int
1559 generate_MULT_EXPR(cctx_T *cctx, isntype_T isn_type, int count)
1560 {
1561     isn_T	*isn;
1562 
1563     if ((isn = generate_instr_drop(cctx, isn_type, count)) == NULL)
1564 	return FAIL;
1565     isn->isn_arg.number = count;
1566 
1567     return OK;
1568 }
1569 
1570     static int
1571 generate_EXEC(cctx_T *cctx, char_u *line)
1572 {
1573     isn_T	*isn;
1574 
1575     RETURN_OK_IF_SKIP(cctx);
1576     if ((isn = generate_instr(cctx, ISN_EXEC)) == NULL)
1577 	return FAIL;
1578     isn->isn_arg.string = vim_strsave(line);
1579     return OK;
1580 }
1581 
1582     static int
1583 generate_EXECCONCAT(cctx_T *cctx, int count)
1584 {
1585     isn_T	*isn;
1586 
1587     if ((isn = generate_instr_drop(cctx, ISN_EXECCONCAT, count)) == NULL)
1588 	return FAIL;
1589     isn->isn_arg.number = count;
1590     return OK;
1591 }
1592 
1593 /*
1594  * Reserve space for a local variable.
1595  * Return the variable or NULL if it failed.
1596  */
1597     static lvar_T *
1598 reserve_local(cctx_T *cctx, char_u *name, size_t len, int isConst, type_T *type)
1599 {
1600     lvar_T  *lvar;
1601 
1602     if (lookup_arg(name, len, NULL, NULL, NULL, cctx) == OK)
1603     {
1604 	emsg_namelen(_(e_str_is_used_as_argument), name, (int)len);
1605 	return NULL;
1606     }
1607 
1608     if (ga_grow(&cctx->ctx_locals, 1) == FAIL)
1609 	return NULL;
1610     lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + cctx->ctx_locals.ga_len++;
1611 
1612     // Every local variable uses the next entry on the stack.  We could re-use
1613     // the last ones when leaving a scope, but then variables used in a closure
1614     // might get overwritten.  To keep things simple do not re-use stack
1615     // entries.  This is less efficient, but memory is cheap these days.
1616     lvar->lv_idx = cctx->ctx_locals_count++;
1617 
1618     lvar->lv_name = vim_strnsave(name, len == 0 ? STRLEN(name) : len);
1619     lvar->lv_const = isConst;
1620     lvar->lv_type = type;
1621 
1622     return lvar;
1623 }
1624 
1625 /*
1626  * Remove local variables above "new_top".
1627  */
1628     static void
1629 unwind_locals(cctx_T *cctx, int new_top)
1630 {
1631     if (cctx->ctx_locals.ga_len > new_top)
1632     {
1633 	int	idx;
1634 	lvar_T	*lvar;
1635 
1636 	for (idx = new_top; idx < cctx->ctx_locals.ga_len; ++idx)
1637 	{
1638 	    lvar = ((lvar_T *)cctx->ctx_locals.ga_data) + idx;
1639 	    vim_free(lvar->lv_name);
1640 	}
1641     }
1642     cctx->ctx_locals.ga_len = new_top;
1643 }
1644 
1645 /*
1646  * Free all local variables.
1647  */
1648     static void
1649 free_locals(cctx_T *cctx)
1650 {
1651     unwind_locals(cctx, 0);
1652     ga_clear(&cctx->ctx_locals);
1653 }
1654 
1655 /*
1656  * Find "name" in script-local items of script "sid".
1657  * Returns the index in "sn_var_vals" if found.
1658  * If found but not in "sn_var_vals" returns -1.
1659  * If not found returns -2.
1660  */
1661     int
1662 get_script_item_idx(int sid, char_u *name, int check_writable)
1663 {
1664     hashtab_T	    *ht;
1665     dictitem_T	    *di;
1666     scriptitem_T    *si = SCRIPT_ITEM(sid);
1667     int		    idx;
1668 
1669     // First look the name up in the hashtable.
1670     if (!SCRIPT_ID_VALID(sid))
1671 	return -1;
1672     ht = &SCRIPT_VARS(sid);
1673     di = find_var_in_ht(ht, 0, name, TRUE);
1674     if (di == NULL)
1675 	return -2;
1676 
1677     // Now find the svar_T index in sn_var_vals.
1678     for (idx = 0; idx < si->sn_var_vals.ga_len; ++idx)
1679     {
1680 	svar_T    *sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
1681 
1682 	if (sv->sv_tv == &di->di_tv)
1683 	{
1684 	    if (check_writable && sv->sv_const)
1685 		semsg(_(e_readonlyvar), name);
1686 	    return idx;
1687 	}
1688     }
1689     return -1;
1690 }
1691 
1692 /*
1693  * Find "name" in imported items of the current script or in "cctx" if not
1694  * NULL.
1695  */
1696     imported_T *
1697 find_imported(char_u *name, size_t len, cctx_T *cctx)
1698 {
1699     int		    idx;
1700 
1701     if (!SCRIPT_ID_VALID(current_sctx.sc_sid))
1702 	return NULL;
1703     if (cctx != NULL)
1704 	for (idx = 0; idx < cctx->ctx_imports.ga_len; ++idx)
1705 	{
1706 	    imported_T *import = ((imported_T *)cctx->ctx_imports.ga_data)
1707 									 + idx;
1708 
1709 	    if (len == 0 ? STRCMP(name, import->imp_name) == 0
1710 			 : STRLEN(import->imp_name) == len
1711 				  && STRNCMP(name, import->imp_name, len) == 0)
1712 		return import;
1713 	}
1714 
1715     return find_imported_in_script(name, len, current_sctx.sc_sid);
1716 }
1717 
1718     imported_T *
1719 find_imported_in_script(char_u *name, size_t len, int sid)
1720 {
1721     scriptitem_T    *si;
1722     int		    idx;
1723 
1724     if (!SCRIPT_ID_VALID(sid))
1725 	return NULL;
1726     si = SCRIPT_ITEM(sid);
1727     for (idx = 0; idx < si->sn_imports.ga_len; ++idx)
1728     {
1729 	imported_T *import = ((imported_T *)si->sn_imports.ga_data) + idx;
1730 
1731 	if (len == 0 ? STRCMP(name, import->imp_name) == 0
1732 		     : STRLEN(import->imp_name) == len
1733 				  && STRNCMP(name, import->imp_name, len) == 0)
1734 	    return import;
1735     }
1736     return NULL;
1737 }
1738 
1739 /*
1740  * Free all imported variables.
1741  */
1742     static void
1743 free_imported(cctx_T *cctx)
1744 {
1745     int idx;
1746 
1747     for (idx = 0; idx < cctx->ctx_imports.ga_len; ++idx)
1748     {
1749 	imported_T *import = ((imported_T *)cctx->ctx_imports.ga_data) + idx;
1750 
1751 	vim_free(import->imp_name);
1752     }
1753     ga_clear(&cctx->ctx_imports);
1754 }
1755 
1756 /*
1757  * Return TRUE if "p" points at a "#" but not at "#{".
1758  */
1759     int
1760 vim9_comment_start(char_u *p)
1761 {
1762     return p[0] == '#' && p[1] != '{';
1763 }
1764 
1765 /*
1766  * Return a pointer to the next line that isn't empty or only contains a
1767  * comment. Skips over white space.
1768  * Returns NULL if there is none.
1769  */
1770     char_u *
1771 peek_next_line_from_context(cctx_T *cctx)
1772 {
1773     int lnum = cctx->ctx_lnum;
1774 
1775     while (++lnum < cctx->ctx_ufunc->uf_lines.ga_len)
1776     {
1777 	char_u *line = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[lnum];
1778 	char_u *p;
1779 
1780 	// ignore NULLs inserted for continuation lines
1781 	if (line != NULL)
1782 	{
1783 	    p = skipwhite(line);
1784 	    if (*p != NUL && !vim9_comment_start(p))
1785 		return p;
1786 	}
1787     }
1788     return NULL;
1789 }
1790 
1791 /*
1792  * Called when checking for a following operator at "arg".  When the rest of
1793  * the line is empty or only a comment, peek the next line.  If there is a next
1794  * line return a pointer to it and set "nextp".
1795  * Otherwise skip over white space.
1796  */
1797     static char_u *
1798 may_peek_next_line(cctx_T *cctx, char_u *arg, char_u **nextp)
1799 {
1800     char_u *p = skipwhite(arg);
1801 
1802     *nextp = NULL;
1803     if (*p == NUL || (VIM_ISWHITE(*arg) && vim9_comment_start(p)))
1804     {
1805 	*nextp = peek_next_line_from_context(cctx);
1806 	if (*nextp != NULL)
1807 	    return *nextp;
1808     }
1809     return p;
1810 }
1811 
1812 /*
1813  * Get the next line of the function from "cctx".
1814  * Skips over empty lines.  Skips over comment lines if "skip_comment" is TRUE.
1815  * Returns NULL when at the end.
1816  */
1817     char_u *
1818 next_line_from_context(cctx_T *cctx, int skip_comment)
1819 {
1820     char_u	*line;
1821 
1822     do
1823     {
1824 	++cctx->ctx_lnum;
1825 	if (cctx->ctx_lnum >= cctx->ctx_ufunc->uf_lines.ga_len)
1826 	{
1827 	    line = NULL;
1828 	    break;
1829 	}
1830 	line = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum];
1831 	cctx->ctx_line_start = line;
1832 	SOURCING_LNUM = cctx->ctx_lnum + 1;
1833     } while (line == NULL || *skipwhite(line) == NUL
1834 		     || (skip_comment && vim9_comment_start(skipwhite(line))));
1835     return line;
1836 }
1837 
1838 /*
1839  * If "*arg" is at the end of the line, advance to the next line.
1840  * Also when "whitep" points to white space and "*arg" is on a "#".
1841  * Return FAIL if beyond the last line, "*arg" is unmodified then.
1842  */
1843     static int
1844 may_get_next_line(char_u *whitep, char_u **arg, cctx_T *cctx)
1845 {
1846     if (**arg == NUL || (VIM_ISWHITE(*whitep) && vim9_comment_start(*arg)))
1847     {
1848 	char_u *next = next_line_from_context(cctx, TRUE);
1849 
1850 	if (next == NULL)
1851 	    return FAIL;
1852 	*arg = skipwhite(next);
1853     }
1854     return OK;
1855 }
1856 
1857 /*
1858  * Idem, and give an error when failed.
1859  */
1860     static int
1861 may_get_next_line_error(char_u *whitep, char_u **arg, cctx_T *cctx)
1862 {
1863     if (may_get_next_line(whitep, arg, cctx) == FAIL)
1864     {
1865 	emsg(_(e_line_incomplete));
1866 	return FAIL;
1867     }
1868     return OK;
1869 }
1870 
1871 
1872 // Structure passed between the compile_expr* functions to keep track of
1873 // constants that have been parsed but for which no code was produced yet.  If
1874 // possible expressions on these constants are applied at compile time.  If
1875 // that is not possible, the code to push the constants needs to be generated
1876 // before other instructions.
1877 // Using 50 should be more than enough of 5 levels of ().
1878 #define PPSIZE 50
1879 typedef struct {
1880     typval_T	pp_tv[PPSIZE];	// stack of ppconst constants
1881     int		pp_used;	// active entries in pp_tv[]
1882 } ppconst_T;
1883 
1884 static int compile_expr0(char_u **arg,  cctx_T *cctx);
1885 static int compile_expr1(char_u **arg,  cctx_T *cctx, ppconst_T *ppconst);
1886 
1887 /*
1888  * Generate a PUSH instruction for "tv".
1889  * "tv" will be consumed or cleared.
1890  * Nothing happens if "tv" is NULL or of type VAR_UNKNOWN;
1891  */
1892     static int
1893 generate_tv_PUSH(cctx_T *cctx, typval_T *tv)
1894 {
1895     if (tv != NULL)
1896     {
1897 	switch (tv->v_type)
1898 	{
1899 	    case VAR_UNKNOWN:
1900 		break;
1901 	    case VAR_BOOL:
1902 		generate_PUSHBOOL(cctx, tv->vval.v_number);
1903 		break;
1904 	    case VAR_SPECIAL:
1905 		generate_PUSHSPEC(cctx, tv->vval.v_number);
1906 		break;
1907 	    case VAR_NUMBER:
1908 		generate_PUSHNR(cctx, tv->vval.v_number);
1909 		break;
1910 #ifdef FEAT_FLOAT
1911 	    case VAR_FLOAT:
1912 		generate_PUSHF(cctx, tv->vval.v_float);
1913 		break;
1914 #endif
1915 	    case VAR_BLOB:
1916 		generate_PUSHBLOB(cctx, tv->vval.v_blob);
1917 		tv->vval.v_blob = NULL;
1918 		break;
1919 	    case VAR_STRING:
1920 		generate_PUSHS(cctx, tv->vval.v_string);
1921 		tv->vval.v_string = NULL;
1922 		break;
1923 	    default:
1924 		iemsg("constant type not supported");
1925 		clear_tv(tv);
1926 		return FAIL;
1927 	}
1928 	tv->v_type = VAR_UNKNOWN;
1929     }
1930     return OK;
1931 }
1932 
1933 /*
1934  * Generate code for any ppconst entries.
1935  */
1936     static int
1937 generate_ppconst(cctx_T *cctx, ppconst_T *ppconst)
1938 {
1939     int	    i;
1940     int	    ret = OK;
1941     int	    save_skip = cctx->ctx_skip;
1942 
1943     cctx->ctx_skip = SKIP_NOT;
1944     for (i = 0; i < ppconst->pp_used; ++i)
1945 	if (generate_tv_PUSH(cctx, &ppconst->pp_tv[i]) == FAIL)
1946 	    ret = FAIL;
1947     ppconst->pp_used = 0;
1948     cctx->ctx_skip = save_skip;
1949     return ret;
1950 }
1951 
1952 /*
1953  * Clear ppconst constants.  Used when failing.
1954  */
1955     static void
1956 clear_ppconst(ppconst_T *ppconst)
1957 {
1958     int	    i;
1959 
1960     for (i = 0; i < ppconst->pp_used; ++i)
1961 	clear_tv(&ppconst->pp_tv[i]);
1962     ppconst->pp_used = 0;
1963 }
1964 
1965 /*
1966  * Generate an instruction to load script-local variable "name", without the
1967  * leading "s:".
1968  * Also finds imported variables.
1969  */
1970     static int
1971 compile_load_scriptvar(
1972 	cctx_T *cctx,
1973 	char_u *name,	    // variable NUL terminated
1974 	char_u *start,	    // start of variable
1975 	char_u **end,	    // end of variable
1976 	int    error)	    // when TRUE may give error
1977 {
1978     scriptitem_T    *si;
1979     int		    idx;
1980     imported_T	    *import;
1981 
1982     if (!SCRIPT_ID_VALID(current_sctx.sc_sid))
1983 	return FAIL;
1984     si = SCRIPT_ITEM(current_sctx.sc_sid);
1985     idx = get_script_item_idx(current_sctx.sc_sid, name, FALSE);
1986     if (idx == -1 || si->sn_version != SCRIPT_VERSION_VIM9)
1987     {
1988 	// variable is not in sn_var_vals: old style script.
1989 	return generate_OLDSCRIPT(cctx, ISN_LOADS, name, current_sctx.sc_sid,
1990 								       &t_any);
1991     }
1992     if (idx >= 0)
1993     {
1994 	svar_T		*sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
1995 
1996 	generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
1997 					current_sctx.sc_sid, idx, sv->sv_type);
1998 	return OK;
1999     }
2000 
2001     import = find_imported(name, 0, cctx);
2002     if (import != NULL)
2003     {
2004 	if (import->imp_all)
2005 	{
2006 	    char_u	*p = skipwhite(*end);
2007 	    char_u	*exp_name;
2008 	    int		cc;
2009 	    ufunc_T	*ufunc;
2010 	    type_T	*type;
2011 
2012 	    // Used "import * as Name", need to lookup the member.
2013 	    if (*p != '.')
2014 	    {
2015 		semsg(_(e_expected_dot_after_name_str), start);
2016 		return FAIL;
2017 	    }
2018 	    ++p;
2019 	    if (VIM_ISWHITE(*p))
2020 	    {
2021 		emsg(_(e_no_white_space_allowed_after_dot));
2022 		return FAIL;
2023 	    }
2024 
2025 	    // isolate one name
2026 	    exp_name = p;
2027 	    while (eval_isnamec(*p))
2028 		++p;
2029 	    cc = *p;
2030 	    *p = NUL;
2031 
2032 	    idx = find_exported(import->imp_sid, exp_name, &ufunc, &type);
2033 	    *p = cc;
2034 	    p = skipwhite(p);
2035 
2036 	    // TODO: what if it is a function?
2037 	    if (idx < 0)
2038 		return FAIL;
2039 	    *end = p;
2040 
2041 	    generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
2042 		    import->imp_sid,
2043 		    idx,
2044 		    type);
2045 	}
2046 	else if (import->imp_funcname != NULL)
2047 	    generate_PUSHFUNC(cctx, import->imp_funcname, import->imp_type);
2048 	else
2049 	    generate_VIM9SCRIPT(cctx, ISN_LOADSCRIPT,
2050 		    import->imp_sid,
2051 		    import->imp_var_vals_idx,
2052 		    import->imp_type);
2053 	return OK;
2054     }
2055 
2056     if (error)
2057 	semsg(_(e_item_not_found_str), name);
2058     return FAIL;
2059 }
2060 
2061     static int
2062 generate_funcref(cctx_T *cctx, char_u *name)
2063 {
2064     ufunc_T *ufunc = find_func(name, FALSE, cctx);
2065 
2066     if (ufunc == NULL)
2067 	return FAIL;
2068 
2069     // Need to compile any default values to get the argument types.
2070     if (ufunc->uf_def_status == UF_TO_BE_COMPILED)
2071 	if (compile_def_function(ufunc, TRUE, NULL) == FAIL)
2072 	    return FAIL;
2073     return generate_PUSHFUNC(cctx, ufunc->uf_name, ufunc->uf_func_type);
2074 }
2075 
2076 /*
2077  * Compile a variable name into a load instruction.
2078  * "end" points to just after the name.
2079  * When "error" is FALSE do not give an error when not found.
2080  */
2081     static int
2082 compile_load(char_u **arg, char_u *end_arg, cctx_T *cctx, int error)
2083 {
2084     type_T	*type;
2085     char_u	*name = NULL;
2086     char_u	*end = end_arg;
2087     int		res = FAIL;
2088     int		prev_called_emsg = called_emsg;
2089 
2090     if (*(*arg + 1) == ':')
2091     {
2092 	// load namespaced variable
2093 	if (end <= *arg + 2)
2094 	{
2095 	    isntype_T  isn_type;
2096 
2097 	    switch (**arg)
2098 	    {
2099 		case 'g': isn_type = ISN_LOADGDICT; break;
2100 		case 'w': isn_type = ISN_LOADWDICT; break;
2101 		case 't': isn_type = ISN_LOADTDICT; break;
2102 		case 'b': isn_type = ISN_LOADBDICT; break;
2103 		default:
2104 		    semsg(_(e_namespace_not_supported_str), *arg);
2105 		    goto theend;
2106 	    }
2107 	    if (generate_instr_type(cctx, isn_type, &t_dict_any) == NULL)
2108 		goto theend;
2109 	    res = OK;
2110 	}
2111 	else
2112 	{
2113 	    isntype_T  isn_type = ISN_DROP;
2114 
2115 	    name = vim_strnsave(*arg + 2, end - (*arg + 2));
2116 	    if (name == NULL)
2117 		return FAIL;
2118 
2119 	    switch (**arg)
2120 	    {
2121 		case 'v': res = generate_LOADV(cctx, name, error);
2122 			  break;
2123 		case 's': res = compile_load_scriptvar(cctx, name,
2124 							    NULL, NULL, error);
2125 			  break;
2126 		case 'g': isn_type = ISN_LOADG; break;
2127 		case 'w': isn_type = ISN_LOADW; break;
2128 		case 't': isn_type = ISN_LOADT; break;
2129 		case 'b': isn_type = ISN_LOADB; break;
2130 		default:  semsg(_(e_namespace_not_supported_str), *arg);
2131 			  goto theend;
2132 	    }
2133 	    if (isn_type != ISN_DROP)
2134 	    {
2135 		// Global, Buffer-local, Window-local and Tabpage-local
2136 		// variables can be defined later, thus we don't check if it
2137 		// exists, give error at runtime.
2138 		res = generate_LOAD(cctx, isn_type, 0, name, &t_any);
2139 	    }
2140 	}
2141     }
2142     else
2143     {
2144 	size_t	    len = end - *arg;
2145 	int	    idx;
2146 	int	    gen_load = FALSE;
2147 	int	    gen_load_outer = FALSE;
2148 
2149 	name = vim_strnsave(*arg, end - *arg);
2150 	if (name == NULL)
2151 	    return FAIL;
2152 
2153 	if (lookup_arg(*arg, len, &idx, &type, &gen_load_outer, cctx) == OK)
2154 	{
2155 	    if (!gen_load_outer)
2156 		gen_load = TRUE;
2157 	}
2158 	else
2159 	{
2160 	    lvar_T *lvar = lookup_local(*arg, len, cctx);
2161 
2162 	    if (lvar != NULL)
2163 	    {
2164 		type = lvar->lv_type;
2165 		idx = lvar->lv_idx;
2166 		if (lvar->lv_from_outer)
2167 		    gen_load_outer = TRUE;
2168 		else
2169 		    gen_load = TRUE;
2170 	    }
2171 	    else
2172 	    {
2173 		// "var" can be script-local even without using "s:" if it
2174 		// already exists in a Vim9 script or when it's imported.
2175 		if (lookup_script(*arg, len, TRUE) == OK
2176 			|| find_imported(name, 0, cctx) != NULL)
2177 		   res = compile_load_scriptvar(cctx, name, *arg, &end, FALSE);
2178 
2179 		// When the name starts with an uppercase letter or "x:" it
2180 		// can be a user defined function.
2181 		// TODO: this is just guessing
2182 		if (res == FAIL && (ASCII_ISUPPER(*name) || name[1] == ':'))
2183 		    res = generate_funcref(cctx, name);
2184 	    }
2185 	}
2186 	if (gen_load)
2187 	    res = generate_LOAD(cctx, ISN_LOAD, idx, NULL, type);
2188 	if (gen_load_outer)
2189 	{
2190 	    res = generate_LOAD(cctx, ISN_LOADOUTER, idx, NULL, type);
2191 	    cctx->ctx_outer_used = TRUE;
2192 	}
2193     }
2194 
2195     *arg = end;
2196 
2197 theend:
2198     if (res == FAIL && error && called_emsg == prev_called_emsg)
2199 	semsg(_(e_variable_not_found_str), name);
2200     vim_free(name);
2201     return res;
2202 }
2203 
2204 /*
2205  * Compile the argument expressions.
2206  * "arg" points to just after the "(" and is advanced to after the ")"
2207  */
2208     static int
2209 compile_arguments(char_u **arg, cctx_T *cctx, int *argcount)
2210 {
2211     char_u  *p = *arg;
2212     char_u  *whitep = *arg;
2213 
2214     for (;;)
2215     {
2216 	if (may_get_next_line(whitep, &p, cctx) == FAIL)
2217 	    goto failret;
2218 	if (*p == ')')
2219 	{
2220 	    *arg = p + 1;
2221 	    return OK;
2222 	}
2223 
2224 	if (compile_expr0(&p, cctx) == FAIL)
2225 	    return FAIL;
2226 	++*argcount;
2227 
2228 	if (*p != ',' && *skipwhite(p) == ',')
2229 	{
2230 	    semsg(_(e_no_white_space_allowed_before_str), ",");
2231 	    p = skipwhite(p);
2232 	}
2233 	if (*p == ',')
2234 	{
2235 	    ++p;
2236 	    if (*p != NUL && !VIM_ISWHITE(*p))
2237 		semsg(_(e_white_space_required_after_str), ",");
2238 	}
2239 	whitep = p;
2240 	p = skipwhite(p);
2241     }
2242 failret:
2243     emsg(_(e_missing_close));
2244     return FAIL;
2245 }
2246 
2247 /*
2248  * Compile a function call:  name(arg1, arg2)
2249  * "arg" points to "name", "arg + varlen" to the "(".
2250  * "argcount_init" is 1 for "value->method()"
2251  * Instructions:
2252  *	EVAL arg1
2253  *	EVAL arg2
2254  *	BCALL / DCALL / UCALL
2255  */
2256     static int
2257 compile_call(
2258 	char_u	    **arg,
2259 	size_t	    varlen,
2260 	cctx_T	    *cctx,
2261 	ppconst_T   *ppconst,
2262 	int	    argcount_init)
2263 {
2264     char_u	*name = *arg;
2265     char_u	*p;
2266     int		argcount = argcount_init;
2267     char_u	namebuf[100];
2268     char_u	fname_buf[FLEN_FIXED + 1];
2269     char_u	*tofree = NULL;
2270     int		error = FCERR_NONE;
2271     ufunc_T	*ufunc;
2272     int		res = FAIL;
2273     int		is_autoload;
2274 
2275     // we can evaluate "has('name')" at compile time
2276     if (varlen == 3 && STRNCMP(*arg, "has", 3) == 0)
2277     {
2278 	char_u	    *s = skipwhite(*arg + varlen + 1);
2279 	typval_T    argvars[2];
2280 
2281 	argvars[0].v_type = VAR_UNKNOWN;
2282 	if (*s == '"')
2283 	    (void)eval_string(&s, &argvars[0], TRUE);
2284 	else if (*s == '\'')
2285 	    (void)eval_lit_string(&s, &argvars[0], TRUE);
2286 	s = skipwhite(s);
2287 	if (*s == ')' && argvars[0].v_type == VAR_STRING)
2288 	{
2289 	    typval_T	*tv = &ppconst->pp_tv[ppconst->pp_used];
2290 
2291 	    *arg = s + 1;
2292 	    argvars[1].v_type = VAR_UNKNOWN;
2293 	    tv->v_type = VAR_NUMBER;
2294 	    tv->vval.v_number = 0;
2295 	    f_has(argvars, tv);
2296 	    clear_tv(&argvars[0]);
2297 	    ++ppconst->pp_used;
2298 	    return OK;
2299 	}
2300 	clear_tv(&argvars[0]);
2301     }
2302 
2303     if (generate_ppconst(cctx, ppconst) == FAIL)
2304 	return FAIL;
2305 
2306     if (varlen >= sizeof(namebuf))
2307     {
2308 	semsg(_(e_name_too_long_str), name);
2309 	return FAIL;
2310     }
2311     vim_strncpy(namebuf, *arg, varlen);
2312     name = fname_trans_sid(namebuf, fname_buf, &tofree, &error);
2313 
2314     *arg = skipwhite(*arg + varlen + 1);
2315     if (compile_arguments(arg, cctx, &argcount) == FAIL)
2316 	goto theend;
2317 
2318     is_autoload = vim_strchr(name, '#') != NULL;
2319     if (ASCII_ISLOWER(*name) && name[1] != ':' && !is_autoload)
2320     {
2321 	int	    idx;
2322 
2323 	// builtin function
2324 	idx = find_internal_func(name);
2325 	if (idx >= 0)
2326 	    res = generate_BCALL(cctx, idx, argcount, argcount_init == 1);
2327 	else
2328 	    semsg(_(e_unknownfunc), namebuf);
2329 	goto theend;
2330     }
2331 
2332     // If we can find the function by name generate the right call.
2333     ufunc = find_func(name, FALSE, cctx);
2334     if (ufunc != NULL)
2335     {
2336 	res = generate_CALL(cctx, ufunc, argcount);
2337 	goto theend;
2338     }
2339 
2340     // If the name is a variable, load it and use PCALL.
2341     // Not for g:Func(), we don't know if it is a variable or not.
2342     // Not for eome#Func(), it will be loaded later.
2343     p = namebuf;
2344     if (STRNCMP(namebuf, "g:", 2) != 0 && !is_autoload
2345 	    && compile_load(&p, namebuf + varlen, cctx, FALSE) == OK)
2346     {
2347 	garray_T    *stack = &cctx->ctx_type_stack;
2348 	type_T	    *type;
2349 
2350 	type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
2351 	res = generate_PCALL(cctx, argcount, namebuf, type, FALSE);
2352 	goto theend;
2353     }
2354 
2355     // A global function may be defined only later.  Need to figure out at
2356     // runtime.  Also handles a FuncRef at runtime.
2357     if (STRNCMP(namebuf, "g:", 2) == 0 || is_autoload)
2358 	res = generate_UCALL(cctx, name, argcount);
2359     else
2360 	semsg(_(e_unknownfunc), namebuf);
2361 
2362 theend:
2363     vim_free(tofree);
2364     return res;
2365 }
2366 
2367 // like NAMESPACE_CHAR but with 'a' and 'l'.
2368 #define VIM9_NAMESPACE_CHAR	(char_u *)"bgstvw"
2369 
2370 /*
2371  * Find the end of a variable or function name.  Unlike find_name_end() this
2372  * does not recognize magic braces.
2373  * When "namespace" is TRUE recognize "b:", "s:", etc.
2374  * Return a pointer to just after the name.  Equal to "arg" if there is no
2375  * valid name.
2376  */
2377     static char_u *
2378 to_name_end(char_u *arg, int namespace)
2379 {
2380     char_u	*p;
2381 
2382     // Quick check for valid starting character.
2383     if (!eval_isnamec1(*arg))
2384 	return arg;
2385 
2386     for (p = arg + 1; *p != NUL && eval_isnamec(*p); MB_PTR_ADV(p))
2387 	// Include a namespace such as "s:var" and "v:var".  But "n:" is not
2388 	// and can be used in slice "[n:]".
2389 	if (*p == ':' && (p != arg + 1
2390 			     || !namespace
2391 			     || vim_strchr(VIM9_NAMESPACE_CHAR, *arg) == NULL))
2392 	    break;
2393     return p;
2394 }
2395 
2396 /*
2397  * Like to_name_end() but also skip over a list or dict constant.
2398  * This intentionally does not handle line continuation.
2399  */
2400     char_u *
2401 to_name_const_end(char_u *arg)
2402 {
2403     char_u	*p = to_name_end(arg, TRUE);
2404     typval_T	rettv;
2405 
2406     if (p == arg && *arg == '[')
2407     {
2408 
2409 	// Can be "[1, 2, 3]->Func()".
2410 	if (eval_list(&p, &rettv, NULL, FALSE) == FAIL)
2411 	    p = arg;
2412     }
2413     else if (p == arg && *arg == '#' && arg[1] == '{')
2414     {
2415 	// Can be "#{a: 1}->Func()".
2416 	++p;
2417 	if (eval_dict(&p, &rettv, NULL, TRUE) == FAIL)
2418 	    p = arg;
2419     }
2420 
2421     return p;
2422 }
2423 
2424 /*
2425  * parse a list: [expr, expr]
2426  * "*arg" points to the '['.
2427  */
2428     static int
2429 compile_list(char_u **arg, cctx_T *cctx)
2430 {
2431     char_u	*p = skipwhite(*arg + 1);
2432     char_u	*whitep = *arg + 1;
2433     int		count = 0;
2434 
2435     for (;;)
2436     {
2437 	if (may_get_next_line(whitep, &p, cctx) == FAIL)
2438 	{
2439 	    semsg(_(e_list_end), *arg);
2440 	    return FAIL;
2441 	}
2442 	if (*p == ',')
2443 	{
2444 	    semsg(_(e_no_white_space_allowed_before_str), ",");
2445 	    return FAIL;
2446 	}
2447 	if (*p == ']')
2448 	{
2449 	    ++p;
2450 	    break;
2451 	}
2452 	if (compile_expr0(&p, cctx) == FAIL)
2453 	    break;
2454 	++count;
2455 	if (*p == ',')
2456 	{
2457 	    ++p;
2458 	    if (*p != ']' && !IS_WHITE_OR_NUL(*p))
2459 	    {
2460 		semsg(_(e_white_space_required_after_str), ",");
2461 		return FAIL;
2462 	    }
2463 	}
2464 	whitep = p;
2465 	p = skipwhite(p);
2466     }
2467     *arg = p;
2468 
2469     generate_NEWLIST(cctx, count);
2470     return OK;
2471 }
2472 
2473 /*
2474  * parse a lambda: {arg, arg -> expr}
2475  * "*arg" points to the '{'.
2476  */
2477     static int
2478 compile_lambda(char_u **arg, cctx_T *cctx)
2479 {
2480     typval_T	rettv;
2481     ufunc_T	*ufunc;
2482     evalarg_T	evalarg;
2483 
2484     CLEAR_FIELD(evalarg);
2485     evalarg.eval_flags = EVAL_EVALUATE;
2486     evalarg.eval_cctx = cctx;
2487 
2488     // Get the funcref in "rettv".
2489     if (get_lambda_tv(arg, &rettv, &evalarg) != OK)
2490 	return FAIL;
2491 
2492     ufunc = rettv.vval.v_partial->pt_func;
2493     ++ufunc->uf_refcount;
2494     clear_tv(&rettv);
2495     ga_init2(&ufunc->uf_type_list, sizeof(type_T *), 10);
2496 
2497     // The function will have one line: "return {expr}".
2498     // Compile it into instructions.
2499     compile_def_function(ufunc, TRUE, cctx);
2500 
2501     clear_evalarg(&evalarg, NULL);
2502 
2503     if (ufunc->uf_def_status == UF_COMPILED)
2504     {
2505 	// The return type will now be known.
2506 	set_function_type(ufunc);
2507 
2508 	return generate_FUNCREF(cctx, ufunc);
2509     }
2510 
2511     func_ptr_unref(ufunc);
2512     return FAIL;
2513 }
2514 
2515 /*
2516  * Compile a lamda call: expr->{lambda}(args)
2517  * "arg" points to the "{".
2518  */
2519     static int
2520 compile_lambda_call(char_u **arg, cctx_T *cctx)
2521 {
2522     ufunc_T	*ufunc;
2523     typval_T	rettv;
2524     int		argcount = 1;
2525     int		ret = FAIL;
2526 
2527     // Get the funcref in "rettv".
2528     if (get_lambda_tv(arg, &rettv, &EVALARG_EVALUATE) == FAIL)
2529 	return FAIL;
2530 
2531     if (**arg != '(')
2532     {
2533 	if (*skipwhite(*arg) == '(')
2534 	    emsg(_(e_nowhitespace));
2535 	else
2536 	    semsg(_(e_missing_paren), "lambda");
2537 	clear_tv(&rettv);
2538 	return FAIL;
2539     }
2540 
2541     ufunc = rettv.vval.v_partial->pt_func;
2542     ++ufunc->uf_refcount;
2543     clear_tv(&rettv);
2544     ga_init2(&ufunc->uf_type_list, sizeof(type_T *), 10);
2545 
2546     // The function will have one line: "return {expr}".
2547     // Compile it into instructions.
2548     compile_def_function(ufunc, TRUE, cctx);
2549 
2550     // compile the arguments
2551     *arg = skipwhite(*arg + 1);
2552     if (compile_arguments(arg, cctx, &argcount) == OK)
2553 	// call the compiled function
2554 	ret = generate_CALL(cctx, ufunc, argcount);
2555 
2556     if (ret == FAIL)
2557 	func_ptr_unref(ufunc);
2558     return ret;
2559 }
2560 
2561 /*
2562  * parse a dict: {'key': val} or #{key: val}
2563  * "*arg" points to the '{'.
2564  */
2565     static int
2566 compile_dict(char_u **arg, cctx_T *cctx, int literal)
2567 {
2568     garray_T	*instr = &cctx->ctx_instr;
2569     garray_T	*stack = &cctx->ctx_type_stack;
2570     int		count = 0;
2571     dict_T	*d = dict_alloc();
2572     dictitem_T	*item;
2573     char_u	*whitep = *arg;
2574     char_u	*p;
2575 
2576     if (d == NULL)
2577 	return FAIL;
2578     *arg = skipwhite(*arg + 1);
2579     for (;;)
2580     {
2581 	char_u *key = NULL;
2582 
2583 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
2584 	{
2585 	    *arg = NULL;
2586 	    goto failret;
2587 	}
2588 
2589 	if (**arg == '}')
2590 	    break;
2591 
2592 	if (literal)
2593 	{
2594 	    char_u *end = to_name_end(*arg, !literal);
2595 
2596 	    if (end == *arg)
2597 	    {
2598 		semsg(_(e_invalid_key_str), *arg);
2599 		return FAIL;
2600 	    }
2601 	    key = vim_strnsave(*arg, end - *arg);
2602 	    if (generate_PUSHS(cctx, key) == FAIL)
2603 		return FAIL;
2604 	    *arg = end;
2605 	}
2606 	else
2607 	{
2608 	    isn_T		*isn;
2609 
2610 	    if (compile_expr0(arg, cctx) == FAIL)
2611 		return FAIL;
2612 	    isn = ((isn_T *)instr->ga_data) + instr->ga_len - 1;
2613 	    if (isn->isn_type == ISN_PUSHS)
2614 		key = isn->isn_arg.string;
2615 	    else
2616 	    {
2617 		type_T *keytype = ((type_T **)stack->ga_data)
2618 							   [stack->ga_len - 1];
2619 		if (need_type(keytype, &t_string, -1, cctx, FALSE) == FAIL)
2620 		    return FAIL;
2621 	    }
2622 	}
2623 
2624 	// Check for duplicate keys, if using string keys.
2625 	if (key != NULL)
2626 	{
2627 	    item = dict_find(d, key, -1);
2628 	    if (item != NULL)
2629 	    {
2630 		semsg(_(e_duplicate_key), key);
2631 		goto failret;
2632 	    }
2633 	    item = dictitem_alloc(key);
2634 	    if (item != NULL)
2635 	    {
2636 		item->di_tv.v_type = VAR_UNKNOWN;
2637 		item->di_tv.v_lock = 0;
2638 		if (dict_add(d, item) == FAIL)
2639 		    dictitem_free(item);
2640 	    }
2641 	}
2642 
2643 	if (**arg != ':')
2644 	{
2645 	    if (*skipwhite(*arg) == ':')
2646 		semsg(_(e_no_white_space_allowed_before_str), ":");
2647 	    else
2648 		semsg(_(e_missing_dict_colon), *arg);
2649 	    return FAIL;
2650 	}
2651 	whitep = *arg + 1;
2652 	if (!IS_WHITE_OR_NUL(*whitep))
2653 	{
2654 	    semsg(_(e_white_space_required_after_str), ":");
2655 	    return FAIL;
2656 	}
2657 
2658 	*arg = skipwhite(*arg + 1);
2659 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
2660 	{
2661 	    *arg = NULL;
2662 	    goto failret;
2663 	}
2664 
2665 	if (compile_expr0(arg, cctx) == FAIL)
2666 	    return FAIL;
2667 	++count;
2668 
2669 	whitep = *arg;
2670 	*arg = skipwhite(*arg);
2671 	if (may_get_next_line(whitep, arg, cctx) == FAIL)
2672 	{
2673 	    *arg = NULL;
2674 	    goto failret;
2675 	}
2676 	if (**arg == '}')
2677 	    break;
2678 	if (**arg != ',')
2679 	{
2680 	    semsg(_(e_missing_dict_comma), *arg);
2681 	    goto failret;
2682 	}
2683 	if (IS_WHITE_OR_NUL(*whitep))
2684 	{
2685 	    semsg(_(e_no_white_space_allowed_before_str), ",");
2686 	    return FAIL;
2687 	}
2688 	whitep = *arg + 1;
2689 	*arg = skipwhite(*arg + 1);
2690     }
2691 
2692     *arg = *arg + 1;
2693 
2694     // Allow for following comment, after at least one space.
2695     p = skipwhite(*arg);
2696     if (VIM_ISWHITE(**arg) && vim9_comment_start(p))
2697 	*arg += STRLEN(*arg);
2698 
2699     dict_unref(d);
2700     return generate_NEWDICT(cctx, count);
2701 
2702 failret:
2703     if (*arg == NULL)
2704 	semsg(_(e_missing_dict_end), _("[end of lines]"));
2705     dict_unref(d);
2706     return FAIL;
2707 }
2708 
2709 /*
2710  * Compile "&option".
2711  */
2712     static int
2713 compile_get_option(char_u **arg, cctx_T *cctx)
2714 {
2715     typval_T	rettv;
2716     char_u	*start = *arg;
2717     int		ret;
2718 
2719     // parse the option and get the current value to get the type.
2720     rettv.v_type = VAR_UNKNOWN;
2721     ret = eval_option(arg, &rettv, TRUE);
2722     if (ret == OK)
2723     {
2724 	// include the '&' in the name, eval_option() expects it.
2725 	char_u *name = vim_strnsave(start, *arg - start);
2726 	type_T	*type = rettv.v_type == VAR_NUMBER ? &t_number : &t_string;
2727 
2728 	ret = generate_LOAD(cctx, ISN_LOADOPT, 0, name, type);
2729 	vim_free(name);
2730     }
2731     clear_tv(&rettv);
2732 
2733     return ret;
2734 }
2735 
2736 /*
2737  * Compile "$VAR".
2738  */
2739     static int
2740 compile_get_env(char_u **arg, cctx_T *cctx)
2741 {
2742     char_u	*start = *arg;
2743     int		len;
2744     int		ret;
2745     char_u	*name;
2746 
2747     ++*arg;
2748     len = get_env_len(arg);
2749     if (len == 0)
2750     {
2751 	semsg(_(e_syntax_error_at_str), start - 1);
2752 	return FAIL;
2753     }
2754 
2755     // include the '$' in the name, eval_env_var() expects it.
2756     name = vim_strnsave(start, len + 1);
2757     ret = generate_LOAD(cctx, ISN_LOADENV, 0, name, &t_string);
2758     vim_free(name);
2759     return ret;
2760 }
2761 
2762 /*
2763  * Compile "@r".
2764  */
2765     static int
2766 compile_get_register(char_u **arg, cctx_T *cctx)
2767 {
2768     int		ret;
2769 
2770     ++*arg;
2771     if (**arg == NUL)
2772     {
2773 	semsg(_(e_syntax_error_at_str), *arg - 1);
2774 	return FAIL;
2775     }
2776     if (!valid_yank_reg(**arg, FALSE))
2777     {
2778 	emsg_invreg(**arg);
2779 	return FAIL;
2780     }
2781     ret = generate_LOAD(cctx, ISN_LOADREG, **arg, NULL, &t_string);
2782     ++*arg;
2783     return ret;
2784 }
2785 
2786 /*
2787  * Apply leading '!', '-' and '+' to constant "rettv".
2788  * When "numeric_only" is TRUE do not apply '!'.
2789  */
2790     static int
2791 apply_leader(typval_T *rettv, int numeric_only, char_u *start, char_u **end)
2792 {
2793     char_u *p = *end;
2794 
2795     // this works from end to start
2796     while (p > start)
2797     {
2798 	--p;
2799 	if (*p == '-' || *p == '+')
2800 	{
2801 	    // only '-' has an effect, for '+' we only check the type
2802 #ifdef FEAT_FLOAT
2803 	    if (rettv->v_type == VAR_FLOAT)
2804 	    {
2805 		if (*p == '-')
2806 		    rettv->vval.v_float = -rettv->vval.v_float;
2807 	    }
2808 	    else
2809 #endif
2810 	    {
2811 		varnumber_T	val;
2812 		int		error = FALSE;
2813 
2814 		// tv_get_number_chk() accepts a string, but we don't want that
2815 		// here
2816 		if (check_not_string(rettv) == FAIL)
2817 		    return FAIL;
2818 		val = tv_get_number_chk(rettv, &error);
2819 		clear_tv(rettv);
2820 		if (error)
2821 		    return FAIL;
2822 		if (*p == '-')
2823 		    val = -val;
2824 		rettv->v_type = VAR_NUMBER;
2825 		rettv->vval.v_number = val;
2826 	    }
2827 	}
2828 	else if (numeric_only)
2829 	{
2830 	    ++p;
2831 	    break;
2832 	}
2833 	else
2834 	{
2835 	    int v = tv2bool(rettv);
2836 
2837 	    // '!' is permissive in the type.
2838 	    clear_tv(rettv);
2839 	    rettv->v_type = VAR_BOOL;
2840 	    rettv->vval.v_number = v ? VVAL_FALSE : VVAL_TRUE;
2841 	}
2842     }
2843     *end = p;
2844     return OK;
2845 }
2846 
2847 /*
2848  * Recognize v: variables that are constants and set "rettv".
2849  */
2850     static void
2851 get_vim_constant(char_u **arg, typval_T *rettv)
2852 {
2853     if (STRNCMP(*arg, "v:true", 6) == 0)
2854     {
2855 	rettv->v_type = VAR_BOOL;
2856 	rettv->vval.v_number = VVAL_TRUE;
2857 	*arg += 6;
2858     }
2859     else if (STRNCMP(*arg, "v:false", 7) == 0)
2860     {
2861 	rettv->v_type = VAR_BOOL;
2862 	rettv->vval.v_number = VVAL_FALSE;
2863 	*arg += 7;
2864     }
2865     else if (STRNCMP(*arg, "v:null", 6) == 0)
2866     {
2867 	rettv->v_type = VAR_SPECIAL;
2868 	rettv->vval.v_number = VVAL_NULL;
2869 	*arg += 6;
2870     }
2871     else if (STRNCMP(*arg, "v:none", 6) == 0)
2872     {
2873 	rettv->v_type = VAR_SPECIAL;
2874 	rettv->vval.v_number = VVAL_NONE;
2875 	*arg += 6;
2876     }
2877 }
2878 
2879     exptype_T
2880 get_compare_type(char_u *p, int *len, int *type_is)
2881 {
2882     exptype_T	type = EXPR_UNKNOWN;
2883     int		i;
2884 
2885     switch (p[0])
2886     {
2887 	case '=':   if (p[1] == '=')
2888 			type = EXPR_EQUAL;
2889 		    else if (p[1] == '~')
2890 			type = EXPR_MATCH;
2891 		    break;
2892 	case '!':   if (p[1] == '=')
2893 			type = EXPR_NEQUAL;
2894 		    else if (p[1] == '~')
2895 			type = EXPR_NOMATCH;
2896 		    break;
2897 	case '>':   if (p[1] != '=')
2898 		    {
2899 			type = EXPR_GREATER;
2900 			*len = 1;
2901 		    }
2902 		    else
2903 			type = EXPR_GEQUAL;
2904 		    break;
2905 	case '<':   if (p[1] != '=')
2906 		    {
2907 			type = EXPR_SMALLER;
2908 			*len = 1;
2909 		    }
2910 		    else
2911 			type = EXPR_SEQUAL;
2912 		    break;
2913 	case 'i':   if (p[1] == 's')
2914 		    {
2915 			// "is" and "isnot"; but not a prefix of a name
2916 			if (p[2] == 'n' && p[3] == 'o' && p[4] == 't')
2917 			    *len = 5;
2918 			i = p[*len];
2919 			if (!isalnum(i) && i != '_')
2920 			{
2921 			    type = *len == 2 ? EXPR_IS : EXPR_ISNOT;
2922 			    *type_is = TRUE;
2923 			}
2924 		    }
2925 		    break;
2926     }
2927     return type;
2928 }
2929 
2930 /*
2931  * Compile code to apply '-', '+' and '!'.
2932  * When "numeric_only" is TRUE do not apply '!'.
2933  */
2934     static int
2935 compile_leader(cctx_T *cctx, int numeric_only, char_u *start, char_u **end)
2936 {
2937     char_u	*p = *end;
2938 
2939     // this works from end to start
2940     while (p > start)
2941     {
2942 	--p;
2943 	if (*p == '-' || *p == '+')
2944 	{
2945 	    int	    negate = *p == '-';
2946 	    isn_T   *isn;
2947 
2948 	    // TODO: check type
2949 	    while (p > start && (p[-1] == '-' || p[-1] == '+'))
2950 	    {
2951 		--p;
2952 		if (*p == '-')
2953 		    negate = !negate;
2954 	    }
2955 	    // only '-' has an effect, for '+' we only check the type
2956 	    if (negate)
2957 		isn = generate_instr(cctx, ISN_NEGATENR);
2958 	    else
2959 		isn = generate_instr(cctx, ISN_CHECKNR);
2960 	    if (isn == NULL)
2961 		return FAIL;
2962 	}
2963 	else if (numeric_only)
2964 	{
2965 	    ++p;
2966 	    break;
2967 	}
2968 	else
2969 	{
2970 	    int  invert = TRUE;
2971 
2972 	    while (p > start && p[-1] == '!')
2973 	    {
2974 		--p;
2975 		invert = !invert;
2976 	    }
2977 	    if (generate_2BOOL(cctx, invert) == FAIL)
2978 		return FAIL;
2979 	}
2980     }
2981     *end = p;
2982     return OK;
2983 }
2984 
2985 /*
2986  * Compile whatever comes after "name" or "name()".
2987  * Advances "*arg" only when something was recognized.
2988  */
2989     static int
2990 compile_subscript(
2991 	char_u **arg,
2992 	cctx_T *cctx,
2993 	char_u *start_leader,
2994 	char_u **end_leader,
2995 	ppconst_T *ppconst)
2996 {
2997     char_u	*name_start = *end_leader;
2998 
2999     for (;;)
3000     {
3001 	char_u *p = skipwhite(*arg);
3002 
3003 	if (*p == NUL || (VIM_ISWHITE(**arg) && vim9_comment_start(p)))
3004 	{
3005 	    char_u *next = peek_next_line_from_context(cctx);
3006 
3007 	    // If a following line starts with "->{" or "->X" advance to that
3008 	    // line, so that a line break before "->" is allowed.
3009 	    // Also if a following line starts with ".x".
3010 	    if (next != NULL &&
3011 		    ((next[0] == '-' && next[1] == '>'
3012 				 && (next[2] == '{' || ASCII_ISALPHA(next[2])))
3013 		    || (next[0] == '.' && eval_isdictc(next[1]))))
3014 	    {
3015 		next = next_line_from_context(cctx, TRUE);
3016 		if (next == NULL)
3017 		    return FAIL;
3018 		*arg = next;
3019 		p = skipwhite(*arg);
3020 	    }
3021 	}
3022 
3023 	// Do not skip over white space to find the "(", "exeucte 'x' ()" is
3024 	// not a function call.
3025 	if (**arg == '(')
3026 	{
3027 	    garray_T    *stack = &cctx->ctx_type_stack;
3028 	    type_T	*type;
3029 	    int		argcount = 0;
3030 
3031 	    if (generate_ppconst(cctx, ppconst) == FAIL)
3032 		return FAIL;
3033 
3034 	    // funcref(arg)
3035 	    type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
3036 
3037 	    *arg = skipwhite(p + 1);
3038 	    if (compile_arguments(arg, cctx, &argcount) == FAIL)
3039 		return FAIL;
3040 	    if (generate_PCALL(cctx, argcount, name_start, type, TRUE) == FAIL)
3041 		return FAIL;
3042 	}
3043 	else if (*p == '-' && p[1] == '>')
3044 	{
3045 	    char_u *pstart = p;
3046 
3047 	    if (generate_ppconst(cctx, ppconst) == FAIL)
3048 		return FAIL;
3049 
3050 	    // something->method()
3051 	    // Apply the '!', '-' and '+' first:
3052 	    //   -1.0->func() works like (-1.0)->func()
3053 	    if (compile_leader(cctx, TRUE, start_leader, end_leader) == FAIL)
3054 		return FAIL;
3055 
3056 	    p += 2;
3057 	    *arg = skipwhite(p);
3058 	    // No line break supported right after "->".
3059 	    if (**arg == '{')
3060 	    {
3061 		// lambda call:  list->{lambda}
3062 		if (compile_lambda_call(arg, cctx) == FAIL)
3063 		    return FAIL;
3064 	    }
3065 	    else
3066 	    {
3067 		// method call:  list->method()
3068 		p = *arg;
3069 		if (!eval_isnamec1(*p))
3070 		{
3071 		    semsg(_(e_trailing_arg), pstart);
3072 		    return FAIL;
3073 		}
3074 		if (ASCII_ISALPHA(*p) && p[1] == ':')
3075 		    p += 2;
3076 		for ( ; eval_isnamec(*p); ++p)
3077 		    ;
3078 		if (*p != '(')
3079 		{
3080 		    semsg(_(e_missing_paren), *arg);
3081 		    return FAIL;
3082 		}
3083 		// TODO: base value may not be the first argument
3084 		if (compile_call(arg, p - *arg, cctx, ppconst, 1) == FAIL)
3085 		    return FAIL;
3086 	    }
3087 	}
3088 	else if (**arg == '[')
3089 	{
3090 	    garray_T	*stack = &cctx->ctx_type_stack;
3091 	    type_T	**typep;
3092 	    type_T	*valtype;
3093 	    vartype_T	vtype;
3094 	    int		is_slice = FALSE;
3095 
3096 	    // list index: list[123]
3097 	    // dict member: dict[key]
3098 	    // string index: text[123]
3099 	    // TODO: blob index
3100 	    // TODO: more arguments
3101 	    // TODO: recognize list or dict at runtime
3102 	    if (generate_ppconst(cctx, ppconst) == FAIL)
3103 		return FAIL;
3104 
3105 	    ++p;
3106 	    *arg = skipwhite(p);
3107 	    if (may_get_next_line_error(p, arg, cctx) == FAIL)
3108 		return FAIL;
3109 	    if (**arg == ':')
3110 		// missing first index is equal to zero
3111 		generate_PUSHNR(cctx, 0);
3112 	    else
3113 	    {
3114 		if (compile_expr0(arg, cctx) == FAIL)
3115 		    return FAIL;
3116 		if (may_get_next_line_error(p, arg, cctx) == FAIL)
3117 		    return FAIL;
3118 		*arg = skipwhite(*arg);
3119 	    }
3120 	    if (**arg == ':')
3121 	    {
3122 		*arg = skipwhite(*arg + 1);
3123 		if (may_get_next_line_error(p, arg, cctx) == FAIL)
3124 		    return FAIL;
3125 		if (**arg == ']')
3126 		    // missing second index is equal to end of string
3127 		    generate_PUSHNR(cctx, -1);
3128 		else
3129 		{
3130 		    if (compile_expr0(arg, cctx) == FAIL)
3131 		    return FAIL;
3132 		    if (may_get_next_line_error(p, arg, cctx) == FAIL)
3133 			return FAIL;
3134 		    *arg = skipwhite(*arg);
3135 		}
3136 		is_slice = TRUE;
3137 	    }
3138 
3139 	    if (**arg != ']')
3140 	    {
3141 		emsg(_(e_missbrac));
3142 		return FAIL;
3143 	    }
3144 	    *arg = *arg + 1;
3145 
3146 	    // We can index a list and a dict.  If we don't know the type
3147 	    // we can use the index value type.
3148 	    // TODO: If we don't know use an instruction to figure it out at
3149 	    // runtime.
3150 	    typep = ((type_T **)stack->ga_data) + stack->ga_len
3151 							  - (is_slice ? 3 : 2);
3152 	    vtype = (*typep)->tt_type;
3153 	    valtype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
3154 	    // If the index is a string, the variable must be a Dict.
3155 	    if (*typep == &t_any && valtype == &t_string)
3156 		vtype = VAR_DICT;
3157 	    if (vtype == VAR_STRING || vtype == VAR_LIST || vtype == VAR_BLOB)
3158 	    {
3159 		if (need_type(valtype, &t_number, -1, cctx, FALSE) == FAIL)
3160 		    return FAIL;
3161 		if (is_slice)
3162 		{
3163 		    valtype = ((type_T **)stack->ga_data)[stack->ga_len - 2];
3164 		    if (need_type(valtype, &t_number, -2, cctx, FALSE) == FAIL)
3165 			return FAIL;
3166 		}
3167 	    }
3168 
3169 	    if (vtype == VAR_DICT)
3170 	    {
3171 		if (is_slice)
3172 		{
3173 		    emsg(_(e_cannot_slice_dictionary));
3174 		    return FAIL;
3175 		}
3176 		if ((*typep)->tt_type == VAR_DICT)
3177 		    *typep = (*typep)->tt_member;
3178 		else
3179 		{
3180 		    if (need_type(*typep, &t_dict_any, -2, cctx, FALSE) == FAIL)
3181 			return FAIL;
3182 		    *typep = &t_any;
3183 		}
3184 		if (may_generate_2STRING(-1, cctx) == FAIL)
3185 		    return FAIL;
3186 		if (generate_instr_drop(cctx, ISN_MEMBER, 1) == FAIL)
3187 		    return FAIL;
3188 	    }
3189 	    else if (vtype == VAR_STRING)
3190 	    {
3191 		*typep = &t_string;
3192 		if ((is_slice
3193 			? generate_instr_drop(cctx, ISN_STRSLICE, 2)
3194 			: generate_instr_drop(cctx, ISN_STRINDEX, 1)) == FAIL)
3195 		    return FAIL;
3196 	    }
3197 	    else if (vtype == VAR_BLOB)
3198 	    {
3199 		emsg("Sorry, blob index and slice not implemented yet");
3200 		return FAIL;
3201 	    }
3202 	    else if (vtype == VAR_LIST || *typep == &t_any)
3203 	    {
3204 		if (is_slice)
3205 		{
3206 		    if (generate_instr_drop(cctx,
3207 			     vtype == VAR_LIST ?  ISN_LISTSLICE : ISN_ANYSLICE,
3208 								    2) == FAIL)
3209 			return FAIL;
3210 		}
3211 		else
3212 		{
3213 		    if ((*typep)->tt_type == VAR_LIST)
3214 			*typep = (*typep)->tt_member;
3215 		    if (generate_instr_drop(cctx,
3216 			     vtype == VAR_LIST ?  ISN_LISTINDEX : ISN_ANYINDEX,
3217 								    1) == FAIL)
3218 			return FAIL;
3219 		}
3220 	    }
3221 	    else
3222 	    {
3223 		emsg(_(e_string_list_dict_or_blob_required));
3224 		return FAIL;
3225 	    }
3226 	}
3227 	else if (*p == '.' && p[1] != '.')
3228 	{
3229 	    if (generate_ppconst(cctx, ppconst) == FAIL)
3230 		return FAIL;
3231 
3232 	    *arg = p + 1;
3233 	    if (may_get_next_line(*arg, arg, cctx) == FAIL)
3234 		return FAIL;
3235 	    // dictionary member: dict.name
3236 	    p = *arg;
3237 	    if (eval_isdictc(*p))
3238 		while (eval_isnamec(*p))
3239 		    MB_PTR_ADV(p);
3240 	    if (p == *arg)
3241 	    {
3242 		semsg(_(e_syntax_error_at_str), *arg);
3243 		return FAIL;
3244 	    }
3245 	    if (generate_STRINGMEMBER(cctx, *arg, p - *arg) == FAIL)
3246 		return FAIL;
3247 	    *arg = p;
3248 	}
3249 	else
3250 	    break;
3251     }
3252 
3253     // TODO - see handle_subscript():
3254     // Turn "dict.Func" into a partial for "Func" bound to "dict".
3255     // Don't do this when "Func" is already a partial that was bound
3256     // explicitly (pt_auto is FALSE).
3257 
3258     return OK;
3259 }
3260 
3261 /*
3262  * Compile an expression at "*arg" and add instructions to "cctx->ctx_instr".
3263  * "arg" is advanced until after the expression, skipping white space.
3264  *
3265  * If the value is a constant "ppconst->pp_ret" will be set.
3266  * Before instructions are generated, any values in "ppconst" will generated.
3267  *
3268  * This is the compiling equivalent of eval1(), eval2(), etc.
3269  */
3270 
3271 /*
3272  *  number		number constant
3273  *  0zFFFFFFFF		Blob constant
3274  *  "string"		string constant
3275  *  'string'		literal string constant
3276  *  &option-name	option value
3277  *  @r			register contents
3278  *  identifier		variable value
3279  *  function()		function call
3280  *  $VAR		environment variable
3281  *  (expression)	nested expression
3282  *  [expr, expr]	List
3283  *  {key: val, key: val}   Dictionary
3284  *  #{key: val, key: val}  Dictionary with literal keys
3285  *
3286  *  Also handle:
3287  *  ! in front		logical NOT
3288  *  - in front		unary minus
3289  *  + in front		unary plus (ignored)
3290  *  trailing (arg)	funcref/partial call
3291  *  trailing []		subscript in String or List
3292  *  trailing .name	entry in Dictionary
3293  *  trailing ->name()	method call
3294  */
3295     static int
3296 compile_expr7(
3297 	char_u **arg,
3298 	cctx_T *cctx,
3299 	ppconst_T *ppconst)
3300 {
3301     char_u	*start_leader, *end_leader;
3302     int		ret = OK;
3303     typval_T	*rettv = &ppconst->pp_tv[ppconst->pp_used];
3304     int		used_before = ppconst->pp_used;
3305 
3306     /*
3307      * Skip '!', '-' and '+' characters.  They are handled later.
3308      */
3309     start_leader = *arg;
3310     while (**arg == '!' || **arg == '-' || **arg == '+')
3311 	*arg = skipwhite(*arg + 1);
3312     end_leader = *arg;
3313 
3314     rettv->v_type = VAR_UNKNOWN;
3315     switch (**arg)
3316     {
3317 	/*
3318 	 * Number constant.
3319 	 */
3320 	case '0':	// also for blob starting with 0z
3321 	case '1':
3322 	case '2':
3323 	case '3':
3324 	case '4':
3325 	case '5':
3326 	case '6':
3327 	case '7':
3328 	case '8':
3329 	case '9':
3330 	case '.':   if (eval_number(arg, rettv, TRUE, FALSE) == FAIL)
3331 			return FAIL;
3332 		    // Apply "-" and "+" just before the number now, right to
3333 		    // left.  Matters especially when "->" follows.  Stops at
3334 		    // '!'.
3335 		    if (apply_leader(rettv, TRUE,
3336 					    start_leader, &end_leader) == FAIL)
3337 		    {
3338 			clear_tv(rettv);
3339 			return FAIL;
3340 		    }
3341 		    break;
3342 
3343 	/*
3344 	 * String constant: "string".
3345 	 */
3346 	case '"':   if (eval_string(arg, rettv, TRUE) == FAIL)
3347 			return FAIL;
3348 		    break;
3349 
3350 	/*
3351 	 * Literal string constant: 'str''ing'.
3352 	 */
3353 	case '\'':  if (eval_lit_string(arg, rettv, TRUE) == FAIL)
3354 			return FAIL;
3355 		    break;
3356 
3357 	/*
3358 	 * Constant Vim variable.
3359 	 */
3360 	case 'v':   get_vim_constant(arg, rettv);
3361 		    ret = NOTDONE;
3362 		    break;
3363 
3364 	/*
3365 	 * "true" constant
3366 	 */
3367 	case 't':   if (STRNCMP(*arg, "true", 4) == 0
3368 						   && !eval_isnamec((*arg)[4]))
3369 		    {
3370 			*arg += 4;
3371 			rettv->v_type = VAR_BOOL;
3372 			rettv->vval.v_number = VVAL_TRUE;
3373 		    }
3374 		    else
3375 			ret = NOTDONE;
3376 		    break;
3377 
3378 	/*
3379 	 * "false" constant
3380 	 */
3381 	case 'f':   if (STRNCMP(*arg, "false", 5) == 0
3382 						   && !eval_isnamec((*arg)[5]))
3383 		    {
3384 			*arg += 5;
3385 			rettv->v_type = VAR_BOOL;
3386 			rettv->vval.v_number = VVAL_FALSE;
3387 		    }
3388 		    else
3389 			ret = NOTDONE;
3390 		    break;
3391 
3392 	/*
3393 	 * List: [expr, expr]
3394 	 */
3395 	case '[':   ret = compile_list(arg, cctx);
3396 		    break;
3397 
3398 	/*
3399 	 * Dictionary: #{key: val, key: val}
3400 	 */
3401 	case '#':   if ((*arg)[1] == '{')
3402 		    {
3403 			++*arg;
3404 			ret = compile_dict(arg, cctx, TRUE);
3405 		    }
3406 		    else
3407 			ret = NOTDONE;
3408 		    break;
3409 
3410 	/*
3411 	 * Lambda: {arg, arg -> expr}
3412 	 * Dictionary: {'key': val, 'key': val}
3413 	 */
3414 	case '{':   {
3415 			char_u *start = skipwhite(*arg + 1);
3416 
3417 			// Find out what comes after the arguments.
3418 			ret = get_function_args(&start, '-', NULL,
3419 					   NULL, NULL, NULL, TRUE, NULL, NULL);
3420 			if (ret != FAIL && *start == '>')
3421 			    ret = compile_lambda(arg, cctx);
3422 			else
3423 			    ret = compile_dict(arg, cctx, FALSE);
3424 		    }
3425 		    break;
3426 
3427 	/*
3428 	 * Option value: &name
3429 	 */
3430 	case '&':	if (generate_ppconst(cctx, ppconst) == FAIL)
3431 			    return FAIL;
3432 			ret = compile_get_option(arg, cctx);
3433 			break;
3434 
3435 	/*
3436 	 * Environment variable: $VAR.
3437 	 */
3438 	case '$':	if (generate_ppconst(cctx, ppconst) == FAIL)
3439 			    return FAIL;
3440 			ret = compile_get_env(arg, cctx);
3441 			break;
3442 
3443 	/*
3444 	 * Register contents: @r.
3445 	 */
3446 	case '@':	if (generate_ppconst(cctx, ppconst) == FAIL)
3447 			    return FAIL;
3448 			ret = compile_get_register(arg, cctx);
3449 			break;
3450 	/*
3451 	 * nested expression: (expression).
3452 	 */
3453 	case '(':   *arg = skipwhite(*arg + 1);
3454 
3455 		    // recursive!
3456 		    if (ppconst->pp_used <= PPSIZE - 10)
3457 		    {
3458 			ret = compile_expr1(arg, cctx, ppconst);
3459 		    }
3460 		    else
3461 		    {
3462 			// Not enough space in ppconst, flush constants.
3463 			if (generate_ppconst(cctx, ppconst) == FAIL)
3464 			    return FAIL;
3465 			ret = compile_expr0(arg, cctx);
3466 		    }
3467 		    *arg = skipwhite(*arg);
3468 		    if (**arg == ')')
3469 			++*arg;
3470 		    else if (ret == OK)
3471 		    {
3472 			emsg(_(e_missing_close));
3473 			ret = FAIL;
3474 		    }
3475 		    break;
3476 
3477 	default:    ret = NOTDONE;
3478 		    break;
3479     }
3480     if (ret == FAIL)
3481 	return FAIL;
3482 
3483     if (rettv->v_type != VAR_UNKNOWN && used_before == ppconst->pp_used)
3484     {
3485 	if (cctx->ctx_skip == SKIP_YES)
3486 	    clear_tv(rettv);
3487 	else
3488 	    // A constant expression can possibly be handled compile time,
3489 	    // return the value instead of generating code.
3490 	    ++ppconst->pp_used;
3491     }
3492     else if (ret == NOTDONE)
3493     {
3494 	char_u	    *p;
3495 	int	    r;
3496 
3497 	if (!eval_isnamec1(**arg))
3498 	{
3499 	    semsg(_(e_name_expected), *arg);
3500 	    return FAIL;
3501 	}
3502 
3503 	// "name" or "name()"
3504 	p = to_name_end(*arg, TRUE);
3505 	if (*p == '(')
3506 	{
3507 	    r = compile_call(arg, p - *arg, cctx, ppconst, 0);
3508 	}
3509 	else
3510 	{
3511 	    if (generate_ppconst(cctx, ppconst) == FAIL)
3512 		return FAIL;
3513 	    r = compile_load(arg, p, cctx, TRUE);
3514 	}
3515 	if (r == FAIL)
3516 	    return FAIL;
3517     }
3518 
3519     // Handle following "[]", ".member", etc.
3520     // Then deal with prefixed '-', '+' and '!', if not done already.
3521     if (compile_subscript(arg, cctx, start_leader, &end_leader,
3522 							     ppconst) == FAIL)
3523 	return FAIL;
3524     if (ppconst->pp_used > 0)
3525     {
3526 	// apply the '!', '-' and '+' before the constant
3527 	rettv = &ppconst->pp_tv[ppconst->pp_used - 1];
3528 	if (apply_leader(rettv, FALSE, start_leader, &end_leader) == FAIL)
3529 	    return FAIL;
3530 	return OK;
3531     }
3532     if (compile_leader(cctx, FALSE, start_leader, &end_leader) == FAIL)
3533 	return FAIL;
3534     return OK;
3535 }
3536 
3537 /*
3538  * Give the "white on both sides" error, taking the operator from "p[len]".
3539  */
3540     void
3541 error_white_both(char_u *op, int len)
3542 {
3543     char_u	buf[10];
3544 
3545     vim_strncpy(buf, op, len);
3546     semsg(_(e_white_space_required_before_and_after_str), buf);
3547 }
3548 
3549 /*
3550  * <type>expr7: runtime type check / conversion
3551  */
3552     static int
3553 compile_expr7t(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3554 {
3555     type_T *want_type = NULL;
3556 
3557     // Recognize <type>
3558     if (**arg == '<' && eval_isnamec1((*arg)[1]))
3559     {
3560 	int		called_emsg_before = called_emsg;
3561 
3562 	++*arg;
3563 	want_type = parse_type(arg, cctx->ctx_type_list);
3564 	if (called_emsg != called_emsg_before)
3565 	    return FAIL;
3566 
3567 	if (**arg != '>')
3568 	{
3569 	    if (*skipwhite(*arg) == '>')
3570 		semsg(_(e_no_white_space_allowed_before_str), ">");
3571 	    else
3572 		emsg(_(e_missing_gt));
3573 	    return FAIL;
3574 	}
3575 	++*arg;
3576 	if (may_get_next_line_error(*arg - 1, arg, cctx) == FAIL)
3577 	    return FAIL;
3578     }
3579 
3580     if (compile_expr7(arg, cctx, ppconst) == FAIL)
3581 	return FAIL;
3582 
3583     if (want_type != NULL)
3584     {
3585 	garray_T    *stack = &cctx->ctx_type_stack;
3586 	type_T	    *actual;
3587 
3588 	generate_ppconst(cctx, ppconst);
3589 	actual = ((type_T **)stack->ga_data)[stack->ga_len - 1];
3590 	if (check_type(want_type, actual, FALSE, 0) == FAIL)
3591 	{
3592 	    if (need_type(actual, want_type, -1, cctx, FALSE) == FAIL)
3593 		return FAIL;
3594 	}
3595     }
3596 
3597     return OK;
3598 }
3599 
3600 /*
3601  *	*	number multiplication
3602  *	/	number division
3603  *	%	number modulo
3604  */
3605     static int
3606 compile_expr6(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3607 {
3608     char_u	*op;
3609     char_u	*next;
3610     int		ppconst_used = ppconst->pp_used;
3611 
3612     // get the first expression
3613     if (compile_expr7t(arg, cctx, ppconst) == FAIL)
3614 	return FAIL;
3615 
3616     /*
3617      * Repeat computing, until no "*", "/" or "%" is following.
3618      */
3619     for (;;)
3620     {
3621 	op = may_peek_next_line(cctx, *arg, &next);
3622 	if (*op != '*' && *op != '/' && *op != '%')
3623 	    break;
3624 	if (next != NULL)
3625 	{
3626 	    *arg = next_line_from_context(cctx, TRUE);
3627 	    op = skipwhite(*arg);
3628 	}
3629 
3630 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(op[1]))
3631 	{
3632 	    error_white_both(op, 1);
3633 	    return FAIL;
3634 	}
3635 	*arg = skipwhite(op + 1);
3636 	if (may_get_next_line(op + 1, arg, cctx) == FAIL)
3637 	    return FAIL;
3638 
3639 	// get the second expression
3640 	if (compile_expr7t(arg, cctx, ppconst) == FAIL)
3641 	    return FAIL;
3642 
3643 	if (ppconst->pp_used == ppconst_used + 2
3644 		&& ppconst->pp_tv[ppconst_used].v_type == VAR_NUMBER
3645 		&& ppconst->pp_tv[ppconst_used + 1].v_type == VAR_NUMBER)
3646 	{
3647 	    typval_T *tv1 = &ppconst->pp_tv[ppconst_used];
3648 	    typval_T *tv2 = &ppconst->pp_tv[ppconst_used + 1];
3649 	    varnumber_T res = 0;
3650 
3651 	    // both are numbers: compute the result
3652 	    switch (*op)
3653 	    {
3654 		case '*': res = tv1->vval.v_number * tv2->vval.v_number;
3655 			  break;
3656 		case '/': res = tv1->vval.v_number / tv2->vval.v_number;
3657 			  break;
3658 		case '%': res = tv1->vval.v_number % tv2->vval.v_number;
3659 			  break;
3660 	    }
3661 	    tv1->vval.v_number = res;
3662 	    --ppconst->pp_used;
3663 	}
3664 	else
3665 	{
3666 	    generate_ppconst(cctx, ppconst);
3667 	    generate_two_op(cctx, op);
3668 	}
3669     }
3670 
3671     return OK;
3672 }
3673 
3674 /*
3675  *      +	number addition
3676  *      -	number subtraction
3677  *      ..	string concatenation
3678  */
3679     static int
3680 compile_expr5(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3681 {
3682     char_u	*op;
3683     char_u	*next;
3684     int		oplen;
3685     int		ppconst_used = ppconst->pp_used;
3686 
3687     // get the first variable
3688     if (compile_expr6(arg, cctx, ppconst) == FAIL)
3689 	return FAIL;
3690 
3691     /*
3692      * Repeat computing, until no "+", "-" or ".." is following.
3693      */
3694     for (;;)
3695     {
3696 	op = may_peek_next_line(cctx, *arg, &next);
3697 	if (*op != '+' && *op != '-' && !(*op == '.' && *(op + 1) == '.'))
3698 	    break;
3699 	oplen = (*op == '.' ? 2 : 1);
3700 	if (next != NULL)
3701 	{
3702 	    *arg = next_line_from_context(cctx, TRUE);
3703 	    op = skipwhite(*arg);
3704 	}
3705 
3706 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(op[oplen]))
3707 	{
3708 	    error_white_both(op, oplen);
3709 	    return FAIL;
3710 	}
3711 
3712 	*arg = skipwhite(op + oplen);
3713 	if (may_get_next_line(op + oplen, arg, cctx) == FAIL)
3714 	    return FAIL;
3715 
3716 	// get the second expression
3717 	if (compile_expr6(arg, cctx, ppconst) == FAIL)
3718 	    return FAIL;
3719 
3720 	if (ppconst->pp_used == ppconst_used + 2
3721 		&& (*op == '.'
3722 		    ? (ppconst->pp_tv[ppconst_used].v_type == VAR_STRING
3723 		    && ppconst->pp_tv[ppconst_used + 1].v_type == VAR_STRING)
3724 		    : (ppconst->pp_tv[ppconst_used].v_type == VAR_NUMBER
3725 		    && ppconst->pp_tv[ppconst_used + 1].v_type == VAR_NUMBER)))
3726 	{
3727 	    typval_T *tv1 = &ppconst->pp_tv[ppconst_used];
3728 	    typval_T *tv2 = &ppconst->pp_tv[ppconst_used + 1];
3729 
3730 	    // concat/subtract/add constant numbers
3731 	    if (*op == '+')
3732 		tv1->vval.v_number = tv1->vval.v_number + tv2->vval.v_number;
3733 	    else if (*op == '-')
3734 		tv1->vval.v_number = tv1->vval.v_number - tv2->vval.v_number;
3735 	    else
3736 	    {
3737 		// concatenate constant strings
3738 		char_u *s1 = tv1->vval.v_string;
3739 		char_u *s2 = tv2->vval.v_string;
3740 		size_t len1 = STRLEN(s1);
3741 
3742 		tv1->vval.v_string = alloc((int)(len1 + STRLEN(s2) + 1));
3743 		if (tv1->vval.v_string == NULL)
3744 		{
3745 		    clear_ppconst(ppconst);
3746 		    return FAIL;
3747 		}
3748 		mch_memmove(tv1->vval.v_string, s1, len1);
3749 		STRCPY(tv1->vval.v_string + len1, s2);
3750 		vim_free(s1);
3751 		vim_free(s2);
3752 	    }
3753 	    --ppconst->pp_used;
3754 	}
3755 	else
3756 	{
3757 	    generate_ppconst(cctx, ppconst);
3758 	    if (*op == '.')
3759 	    {
3760 		if (may_generate_2STRING(-2, cctx) == FAIL
3761 			|| may_generate_2STRING(-1, cctx) == FAIL)
3762 		    return FAIL;
3763 		generate_instr_drop(cctx, ISN_CONCAT, 1);
3764 	    }
3765 	    else
3766 		generate_two_op(cctx, op);
3767 	}
3768     }
3769 
3770     return OK;
3771 }
3772 
3773 /*
3774  * expr5a == expr5b
3775  * expr5a =~ expr5b
3776  * expr5a != expr5b
3777  * expr5a !~ expr5b
3778  * expr5a > expr5b
3779  * expr5a >= expr5b
3780  * expr5a < expr5b
3781  * expr5a <= expr5b
3782  * expr5a is expr5b
3783  * expr5a isnot expr5b
3784  *
3785  * Produces instructions:
3786  *	EVAL expr5a		Push result of "expr5a"
3787  *	EVAL expr5b		Push result of "expr5b"
3788  *	COMPARE			one of the compare instructions
3789  */
3790     static int
3791 compile_expr4(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3792 {
3793     exptype_T	type = EXPR_UNKNOWN;
3794     char_u	*p;
3795     char_u	*next;
3796     int		len = 2;
3797     int		type_is = FALSE;
3798     int		ppconst_used = ppconst->pp_used;
3799 
3800     // get the first variable
3801     if (compile_expr5(arg, cctx, ppconst) == FAIL)
3802 	return FAIL;
3803 
3804     p = may_peek_next_line(cctx, *arg, &next);
3805     type = get_compare_type(p, &len, &type_is);
3806 
3807     /*
3808      * If there is a comparative operator, use it.
3809      */
3810     if (type != EXPR_UNKNOWN)
3811     {
3812 	int ic = FALSE;  // Default: do not ignore case
3813 
3814 	if (next != NULL)
3815 	{
3816 	    *arg = next_line_from_context(cctx, TRUE);
3817 	    p = skipwhite(*arg);
3818 	}
3819 	if (type_is && (p[len] == '?' || p[len] == '#'))
3820 	{
3821 	    semsg(_(e_invexpr2), *arg);
3822 	    return FAIL;
3823 	}
3824 	// extra question mark appended: ignore case
3825 	if (p[len] == '?')
3826 	{
3827 	    ic = TRUE;
3828 	    ++len;
3829 	}
3830 	// extra '#' appended: match case (ignored)
3831 	else if (p[len] == '#')
3832 	    ++len;
3833 	// nothing appended: match case
3834 
3835 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[len]))
3836 	{
3837 	    error_white_both(p, len);
3838 	    return FAIL;
3839 	}
3840 
3841 	// get the second variable
3842 	*arg = skipwhite(p + len);
3843 	if (may_get_next_line(p + len, arg, cctx) == FAIL)
3844 	    return FAIL;
3845 
3846 	if (compile_expr5(arg, cctx, ppconst) == FAIL)
3847 	    return FAIL;
3848 
3849 	if (ppconst->pp_used == ppconst_used + 2)
3850 	{
3851 	    typval_T *	tv1 = &ppconst->pp_tv[ppconst->pp_used - 2];
3852 	    typval_T	*tv2 = &ppconst->pp_tv[ppconst->pp_used - 1];
3853 	    int		ret;
3854 
3855 	    // Both sides are a constant, compute the result now.
3856 	    // First check for a valid combination of types, this is more
3857 	    // strict than typval_compare().
3858 	    if (check_compare_types(type, tv1, tv2) == FAIL)
3859 		ret = FAIL;
3860 	    else
3861 	    {
3862 		ret = typval_compare(tv1, tv2, type, ic);
3863 		tv1->v_type = VAR_BOOL;
3864 		tv1->vval.v_number = tv1->vval.v_number
3865 						      ? VVAL_TRUE : VVAL_FALSE;
3866 		clear_tv(tv2);
3867 		--ppconst->pp_used;
3868 	    }
3869 	    return ret;
3870 	}
3871 
3872 	generate_ppconst(cctx, ppconst);
3873 	return generate_COMPARE(cctx, type, ic);
3874     }
3875 
3876     return OK;
3877 }
3878 
3879 static int compile_expr3(char_u **arg,  cctx_T *cctx, ppconst_T *ppconst);
3880 
3881 /*
3882  * Compile || or &&.
3883  */
3884     static int
3885 compile_and_or(
3886 	char_u **arg,
3887 	cctx_T	*cctx,
3888 	char	*op,
3889 	ppconst_T *ppconst,
3890 	int	ppconst_used UNUSED)
3891 {
3892     char_u	*next;
3893     char_u	*p = may_peek_next_line(cctx, *arg, &next);
3894     int		opchar = *op;
3895 
3896     if (p[0] == opchar && p[1] == opchar)
3897     {
3898 	garray_T	*instr = &cctx->ctx_instr;
3899 	garray_T	end_ga;
3900 
3901 	/*
3902 	 * Repeat until there is no following "||" or "&&"
3903 	 */
3904 	ga_init2(&end_ga, sizeof(int), 10);
3905 	while (p[0] == opchar && p[1] == opchar)
3906 	{
3907 	    if (next != NULL)
3908 	    {
3909 		*arg = next_line_from_context(cctx, TRUE);
3910 		p = skipwhite(*arg);
3911 	    }
3912 
3913 	    if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[2]))
3914 	    {
3915 		semsg(_(e_white_space_required_before_and_after_str), op);
3916 		return FAIL;
3917 	    }
3918 
3919 	    // TODO: use ppconst if the value is a constant
3920 	    generate_ppconst(cctx, ppconst);
3921 
3922 	    if (ga_grow(&end_ga, 1) == FAIL)
3923 	    {
3924 		ga_clear(&end_ga);
3925 		return FAIL;
3926 	    }
3927 	    *(((int *)end_ga.ga_data) + end_ga.ga_len) = instr->ga_len;
3928 	    ++end_ga.ga_len;
3929 	    generate_JUMP(cctx, opchar == '|'
3930 			 ?  JUMP_AND_KEEP_IF_TRUE : JUMP_AND_KEEP_IF_FALSE, 0);
3931 
3932 	    // eval the next expression
3933 	    *arg = skipwhite(p + 2);
3934 	    if (may_get_next_line(p + 2, arg, cctx) == FAIL)
3935 		return FAIL;
3936 
3937 	    if ((opchar == '|' ? compile_expr3(arg, cctx, ppconst)
3938 				  : compile_expr4(arg, cctx, ppconst)) == FAIL)
3939 	    {
3940 		ga_clear(&end_ga);
3941 		return FAIL;
3942 	    }
3943 
3944 	    p = may_peek_next_line(cctx, *arg, &next);
3945 	}
3946 	generate_ppconst(cctx, ppconst);
3947 
3948 	// Fill in the end label in all jumps.
3949 	while (end_ga.ga_len > 0)
3950 	{
3951 	    isn_T	*isn;
3952 
3953 	    --end_ga.ga_len;
3954 	    isn = ((isn_T *)instr->ga_data)
3955 				  + *(((int *)end_ga.ga_data) + end_ga.ga_len);
3956 	    isn->isn_arg.jump.jump_where = instr->ga_len;
3957 	}
3958 	ga_clear(&end_ga);
3959     }
3960 
3961     return OK;
3962 }
3963 
3964 /*
3965  * expr4a && expr4a && expr4a	    logical AND
3966  *
3967  * Produces instructions:
3968  *	EVAL expr4a		Push result of "expr4a"
3969  *	JUMP_AND_KEEP_IF_FALSE end
3970  *	EVAL expr4b		Push result of "expr4b"
3971  *	JUMP_AND_KEEP_IF_FALSE end
3972  *	EVAL expr4c		Push result of "expr4c"
3973  * end:
3974  */
3975     static int
3976 compile_expr3(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
3977 {
3978     int		ppconst_used = ppconst->pp_used;
3979 
3980     // get the first variable
3981     if (compile_expr4(arg, cctx, ppconst) == FAIL)
3982 	return FAIL;
3983 
3984     // || and && work almost the same
3985     return compile_and_or(arg, cctx, "&&", ppconst, ppconst_used);
3986 }
3987 
3988 /*
3989  * expr3a || expr3b || expr3c	    logical OR
3990  *
3991  * Produces instructions:
3992  *	EVAL expr3a		Push result of "expr3a"
3993  *	JUMP_AND_KEEP_IF_TRUE end
3994  *	EVAL expr3b		Push result of "expr3b"
3995  *	JUMP_AND_KEEP_IF_TRUE end
3996  *	EVAL expr3c		Push result of "expr3c"
3997  * end:
3998  */
3999     static int
4000 compile_expr2(char_u **arg, cctx_T *cctx, ppconst_T *ppconst)
4001 {
4002     int		ppconst_used = ppconst->pp_used;
4003 
4004     // eval the first expression
4005     if (compile_expr3(arg, cctx, ppconst) == FAIL)
4006 	return FAIL;
4007 
4008     // || and && work almost the same
4009     return compile_and_or(arg, cctx, "||", ppconst, ppconst_used);
4010 }
4011 
4012 /*
4013  * Toplevel expression: expr2 ? expr1a : expr1b
4014  *
4015  * Produces instructions:
4016  *	EVAL expr2		Push result of "expr"
4017  *      JUMP_IF_FALSE alt	jump if false
4018  *      EVAL expr1a
4019  *      JUMP_ALWAYS end
4020  * alt:	EVAL expr1b
4021  * end:
4022  */
4023     static int
4024 compile_expr1(char_u **arg,  cctx_T *cctx, ppconst_T *ppconst)
4025 {
4026     char_u	*p;
4027     int		ppconst_used = ppconst->pp_used;
4028     char_u	*next;
4029 
4030     // Ignore all kinds of errors when not producing code.
4031     if (cctx->ctx_skip == SKIP_YES)
4032     {
4033 	skip_expr(arg);
4034 	return OK;
4035     }
4036 
4037     // Evaluate the first expression.
4038     if (compile_expr2(arg, cctx, ppconst) == FAIL)
4039 	return FAIL;
4040 
4041     p = may_peek_next_line(cctx, *arg, &next);
4042     if (*p == '?')
4043     {
4044 	garray_T	*instr = &cctx->ctx_instr;
4045 	garray_T	*stack = &cctx->ctx_type_stack;
4046 	int		alt_idx = instr->ga_len;
4047 	int		end_idx = 0;
4048 	isn_T		*isn;
4049 	type_T		*type1 = NULL;
4050 	type_T		*type2;
4051 	int		has_const_expr = FALSE;
4052 	int		const_value = FALSE;
4053 	int		save_skip = cctx->ctx_skip;
4054 
4055 	if (next != NULL)
4056 	{
4057 	    *arg = next_line_from_context(cctx, TRUE);
4058 	    p = skipwhite(*arg);
4059 	}
4060 
4061 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[1]))
4062 	{
4063 	    semsg(_(e_white_space_required_before_and_after_str), "?");
4064 	    return FAIL;
4065 	}
4066 
4067 	if (ppconst->pp_used == ppconst_used + 1)
4068 	{
4069 	    // the condition is a constant, we know whether the ? or the :
4070 	    // expression is to be evaluated.
4071 	    has_const_expr = TRUE;
4072 	    const_value = tv2bool(&ppconst->pp_tv[ppconst_used]);
4073 	    clear_tv(&ppconst->pp_tv[ppconst_used]);
4074 	    --ppconst->pp_used;
4075 	    cctx->ctx_skip = save_skip == SKIP_YES || !const_value
4076 							 ? SKIP_YES : SKIP_NOT;
4077 	}
4078 	else
4079 	{
4080 	    generate_ppconst(cctx, ppconst);
4081 	    generate_JUMP(cctx, JUMP_IF_FALSE, 0);
4082 	}
4083 
4084 	// evaluate the second expression; any type is accepted
4085 	*arg = skipwhite(p + 1);
4086 	if (may_get_next_line(p + 1, arg, cctx) == FAIL)
4087 	    return FAIL;
4088 	if (compile_expr1(arg, cctx, ppconst) == FAIL)
4089 	    return FAIL;
4090 
4091 	if (!has_const_expr)
4092 	{
4093 	    generate_ppconst(cctx, ppconst);
4094 
4095 	    // remember the type and drop it
4096 	    --stack->ga_len;
4097 	    type1 = ((type_T **)stack->ga_data)[stack->ga_len];
4098 
4099 	    end_idx = instr->ga_len;
4100 	    generate_JUMP(cctx, JUMP_ALWAYS, 0);
4101 
4102 	    // jump here from JUMP_IF_FALSE
4103 	    isn = ((isn_T *)instr->ga_data) + alt_idx;
4104 	    isn->isn_arg.jump.jump_where = instr->ga_len;
4105 	}
4106 
4107 	// Check for the ":".
4108 	p = may_peek_next_line(cctx, *arg, &next);
4109 	if (*p != ':')
4110 	{
4111 	    emsg(_(e_missing_colon));
4112 	    return FAIL;
4113 	}
4114 	if (next != NULL)
4115 	{
4116 	    *arg = next_line_from_context(cctx, TRUE);
4117 	    p = skipwhite(*arg);
4118 	}
4119 
4120 	if (!IS_WHITE_OR_NUL(**arg) || !IS_WHITE_OR_NUL(p[1]))
4121 	{
4122 	    semsg(_(e_white_space_required_before_and_after_str), ":");
4123 	    return FAIL;
4124 	}
4125 
4126 	// evaluate the third expression
4127 	if (has_const_expr)
4128 	    cctx->ctx_skip = save_skip == SKIP_YES || const_value
4129 							 ? SKIP_YES : SKIP_NOT;
4130 	*arg = skipwhite(p + 1);
4131 	if (may_get_next_line(p + 1, arg, cctx) == FAIL)
4132 	    return FAIL;
4133 	if (compile_expr1(arg, cctx, ppconst) == FAIL)
4134 	    return FAIL;
4135 
4136 	if (!has_const_expr)
4137 	{
4138 	    generate_ppconst(cctx, ppconst);
4139 
4140 	    // If the types differ, the result has a more generic type.
4141 	    type2 = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4142 	    common_type(type1, type2, &type2, cctx->ctx_type_list);
4143 
4144 	    // jump here from JUMP_ALWAYS
4145 	    isn = ((isn_T *)instr->ga_data) + end_idx;
4146 	    isn->isn_arg.jump.jump_where = instr->ga_len;
4147 	}
4148 
4149 	cctx->ctx_skip = save_skip;
4150     }
4151     return OK;
4152 }
4153 
4154 /*
4155  * Toplevel expression.
4156  */
4157     static int
4158 compile_expr0(char_u **arg,  cctx_T *cctx)
4159 {
4160     ppconst_T	ppconst;
4161 
4162     CLEAR_FIELD(ppconst);
4163     if (compile_expr1(arg, cctx, &ppconst) == FAIL)
4164     {
4165 	clear_ppconst(&ppconst);
4166 	return FAIL;
4167     }
4168     if (generate_ppconst(cctx, &ppconst) == FAIL)
4169 	return FAIL;
4170     return OK;
4171 }
4172 
4173 /*
4174  * compile "return [expr]"
4175  */
4176     static char_u *
4177 compile_return(char_u *arg, int set_return_type, cctx_T *cctx)
4178 {
4179     char_u	*p = arg;
4180     garray_T	*stack = &cctx->ctx_type_stack;
4181     type_T	*stack_type;
4182 
4183     if (*p != NUL && *p != '|' && *p != '\n')
4184     {
4185 	// compile return argument into instructions
4186 	if (compile_expr0(&p, cctx) == FAIL)
4187 	    return NULL;
4188 
4189 	stack_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
4190 	if (set_return_type)
4191 	    cctx->ctx_ufunc->uf_ret_type = stack_type;
4192 	else
4193 	{
4194 	    if (cctx->ctx_ufunc->uf_ret_type->tt_type == VAR_VOID
4195 		    && stack_type->tt_type != VAR_VOID
4196 		    && stack_type->tt_type != VAR_UNKNOWN)
4197 	    {
4198 		emsg(_(e_returning_value_in_function_without_return_type));
4199 		return NULL;
4200 	    }
4201 	    if (need_type(stack_type, cctx->ctx_ufunc->uf_ret_type, -1,
4202 							  cctx, FALSE) == FAIL)
4203 	    return NULL;
4204 	}
4205     }
4206     else
4207     {
4208 	// "set_return_type" cannot be TRUE, only used for a lambda which
4209 	// always has an argument.
4210 	if (cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_VOID
4211 		&& cctx->ctx_ufunc->uf_ret_type->tt_type != VAR_UNKNOWN)
4212 	{
4213 	    emsg(_(e_missing_return_value));
4214 	    return NULL;
4215 	}
4216 
4217 	// No argument, return zero.
4218 	generate_PUSHNR(cctx, 0);
4219     }
4220 
4221     if (generate_instr(cctx, ISN_RETURN) == NULL)
4222 	return NULL;
4223 
4224     // "return val | endif" is possible
4225     return skipwhite(p);
4226 }
4227 
4228 /*
4229  * Get a line from the compilation context, compatible with exarg_T getline().
4230  * Return a pointer to the line in allocated memory.
4231  * Return NULL for end-of-file or some error.
4232  */
4233     static char_u *
4234 exarg_getline(
4235 	int c UNUSED,
4236 	void *cookie,
4237 	int indent UNUSED,
4238 	getline_opt_T options UNUSED)
4239 {
4240     cctx_T  *cctx = (cctx_T *)cookie;
4241     char_u  *p;
4242 
4243     for (;;)
4244     {
4245 	if (cctx->ctx_lnum == cctx->ctx_ufunc->uf_lines.ga_len)
4246 	    return NULL;
4247 	++cctx->ctx_lnum;
4248 	p = ((char_u **)cctx->ctx_ufunc->uf_lines.ga_data)[cctx->ctx_lnum];
4249 	// Comment lines result in NULL pointers, skip them.
4250 	if (p != NULL)
4251 	    return vim_strsave(p);
4252     }
4253 }
4254 
4255 /*
4256  * Compile a nested :def command.
4257  */
4258     static char_u *
4259 compile_nested_function(exarg_T *eap, cctx_T *cctx)
4260 {
4261     int		is_global = *eap->arg == 'g' && eap->arg[1] == ':';
4262     char_u	*name_start = eap->arg;
4263     char_u	*name_end = to_name_end(eap->arg, TRUE);
4264     char_u	*lambda_name;
4265     lvar_T	*lvar;
4266     ufunc_T	*ufunc;
4267     int		r;
4268 
4269     // Only g:Func() can use a namespace.
4270     if (name_start[1] == ':' && !is_global)
4271     {
4272 	semsg(_(e_namespace_not_supported_str), name_start);
4273 	return NULL;
4274     }
4275     if (check_defined(name_start, name_end - name_start, cctx) == FAIL)
4276 	return NULL;
4277 
4278     eap->arg = name_end;
4279     eap->getline = exarg_getline;
4280     eap->cookie = cctx;
4281     eap->skip = cctx->ctx_skip == SKIP_YES;
4282     eap->forceit = FALSE;
4283     lambda_name = get_lambda_name();
4284     ufunc = def_function(eap, lambda_name);
4285 
4286     if (ufunc == NULL)
4287 	return eap->skip ? (char_u *)"" : NULL;
4288     if (ufunc->uf_def_status == UF_TO_BE_COMPILED
4289 	    && compile_def_function(ufunc, TRUE, cctx) == FAIL)
4290 	return NULL;
4291 
4292     if (is_global)
4293     {
4294 	char_u *func_name = vim_strnsave(name_start + 2,
4295 						    name_end - name_start - 2);
4296 
4297 	if (func_name == NULL)
4298 	    r = FAIL;
4299 	else
4300 	    r = generate_NEWFUNC(cctx, lambda_name, func_name);
4301     }
4302     else
4303     {
4304 	// Define a local variable for the function reference.
4305 	lvar = reserve_local(cctx, name_start, name_end - name_start,
4306 						    TRUE, ufunc->uf_func_type);
4307 	if (lvar == NULL)
4308 	    return NULL;
4309 	if (generate_FUNCREF(cctx, ufunc) == FAIL)
4310 	    return NULL;
4311 	r = generate_STORE(cctx, ISN_STORE, lvar->lv_idx, NULL);
4312     }
4313 
4314     // TODO: warning for trailing text?
4315     return r == FAIL ? NULL : (char_u *)"";
4316 }
4317 
4318 /*
4319  * Return the length of an assignment operator, or zero if there isn't one.
4320  */
4321     int
4322 assignment_len(char_u *p, int *heredoc)
4323 {
4324     if (*p == '=')
4325     {
4326 	if (p[1] == '<' && p[2] == '<')
4327 	{
4328 	    *heredoc = TRUE;
4329 	    return 3;
4330 	}
4331 	return 1;
4332     }
4333     if (vim_strchr((char_u *)"+-*/%", *p) != NULL && p[1] == '=')
4334 	return 2;
4335     if (STRNCMP(p, "..=", 3) == 0)
4336 	return 3;
4337     return 0;
4338 }
4339 
4340 // words that cannot be used as a variable
4341 static char *reserved[] = {
4342     "true",
4343     "false",
4344     NULL
4345 };
4346 
4347 typedef enum {
4348     dest_local,
4349     dest_option,
4350     dest_env,
4351     dest_global,
4352     dest_buffer,
4353     dest_window,
4354     dest_tab,
4355     dest_vimvar,
4356     dest_script,
4357     dest_reg,
4358 } assign_dest_T;
4359 
4360 /*
4361  * Generate the load instruction for "name".
4362  */
4363     static void
4364 generate_loadvar(
4365 	cctx_T		*cctx,
4366 	assign_dest_T	dest,
4367 	char_u		*name,
4368 	lvar_T		*lvar,
4369 	type_T		*type)
4370 {
4371     switch (dest)
4372     {
4373 	case dest_option:
4374 	    // TODO: check the option exists
4375 	    generate_LOAD(cctx, ISN_LOADOPT, 0, name, type);
4376 	    break;
4377 	case dest_global:
4378 	    generate_LOAD(cctx, ISN_LOADG, 0, name + 2, type);
4379 	    break;
4380 	case dest_buffer:
4381 	    generate_LOAD(cctx, ISN_LOADB, 0, name + 2, type);
4382 	    break;
4383 	case dest_window:
4384 	    generate_LOAD(cctx, ISN_LOADW, 0, name + 2, type);
4385 	    break;
4386 	case dest_tab:
4387 	    generate_LOAD(cctx, ISN_LOADT, 0, name + 2, type);
4388 	    break;
4389 	case dest_script:
4390 	    compile_load_scriptvar(cctx,
4391 		    name + (name[1] == ':' ? 2 : 0), NULL, NULL, TRUE);
4392 	    break;
4393 	case dest_env:
4394 	    // Include $ in the name here
4395 	    generate_LOAD(cctx, ISN_LOADENV, 0, name, type);
4396 	    break;
4397 	case dest_reg:
4398 	    generate_LOAD(cctx, ISN_LOADREG, name[1], NULL, &t_string);
4399 	    break;
4400 	case dest_vimvar:
4401 	    generate_LOADV(cctx, name + 2, TRUE);
4402 	    break;
4403 	case dest_local:
4404 	    if (lvar->lv_from_outer)
4405 		generate_LOAD(cctx, ISN_LOADOUTER, lvar->lv_idx,
4406 							   NULL, type);
4407 	    else
4408 		generate_LOAD(cctx, ISN_LOAD, lvar->lv_idx, NULL, type);
4409 	    break;
4410     }
4411 }
4412 
4413     void
4414 vim9_declare_error(char_u *name)
4415 {
4416     char *scope = "";
4417 
4418     switch (*name)
4419     {
4420 	case 'g': scope = _("global"); break;
4421 	case 'b': scope = _("buffer"); break;
4422 	case 'w': scope = _("window"); break;
4423 	case 't': scope = _("tab"); break;
4424 	case 'v': scope = "v:"; break;
4425 	case '$': semsg(_(e_cannot_declare_an_environment_variable), name);
4426 		  return;
4427 	case '&': semsg(_(e_cannot_declare_an_option), name);
4428 		  return;
4429 	case '@': semsg(_(e_cannot_declare_a_register_str), name);
4430 		  return;
4431 	default: return;
4432     }
4433     semsg(_(e_cannot_declare_a_scope_variable), scope, name);
4434 }
4435 
4436 /*
4437  * Compile declaration and assignment:
4438  * "let var", "let var = expr", "const var = expr" and "var = expr"
4439  * "arg" points to "var".
4440  * Return NULL for an error.
4441  * Return "arg" if it does not look like a variable list.
4442  */
4443     static char_u *
4444 compile_assignment(char_u *arg, exarg_T *eap, cmdidx_T cmdidx, cctx_T *cctx)
4445 {
4446     char_u	*var_start;
4447     char_u	*p;
4448     char_u	*end = arg;
4449     char_u	*ret = NULL;
4450     int		var_count = 0;
4451     int		var_idx;
4452     int		scriptvar_sid = 0;
4453     int		scriptvar_idx = -1;
4454     int		semicolon = 0;
4455     garray_T	*instr = &cctx->ctx_instr;
4456     garray_T    *stack = &cctx->ctx_type_stack;
4457     char_u	*op;
4458     int		oplen = 0;
4459     int		heredoc = FALSE;
4460     type_T	*type = &t_any;
4461     type_T	*member_type = &t_any;
4462     char_u	*name = NULL;
4463     char_u	*sp;
4464     int		is_decl = cmdidx == CMD_let || cmdidx == CMD_const;
4465 
4466     // Skip over the "var" or "[var, var]" to get to any "=".
4467     p = skip_var_list(arg, TRUE, &var_count, &semicolon, TRUE);
4468     if (p == NULL)
4469 	return *arg == '[' ? arg : NULL;
4470 
4471     if (var_count > 0 && is_decl)
4472     {
4473 	// TODO: should we allow this, and figure out type inference from list
4474 	// members?
4475 	emsg(_(e_cannot_use_list_for_declaration));
4476 	return NULL;
4477     }
4478 
4479     sp = p;
4480     p = skipwhite(p);
4481     op = p;
4482     oplen = assignment_len(p, &heredoc);
4483 
4484     if (var_count > 0 && oplen == 0)
4485 	// can be something like "[1, 2]->func()"
4486 	return arg;
4487 
4488     if (oplen > 0 && (!VIM_ISWHITE(*sp) || !VIM_ISWHITE(op[oplen])))
4489     {
4490 	error_white_both(op, oplen);
4491 	return NULL;
4492     }
4493 
4494     if (heredoc)
4495     {
4496 	list_T	   *l;
4497 	listitem_T *li;
4498 
4499 	// [let] varname =<< [trim] {end}
4500 	eap->getline = exarg_getline;
4501 	eap->cookie = cctx;
4502 	l = heredoc_get(eap, op + 3, FALSE);
4503 
4504 	// Push each line and the create the list.
4505 	FOR_ALL_LIST_ITEMS(l, li)
4506 	{
4507 	    generate_PUSHS(cctx, li->li_tv.vval.v_string);
4508 	    li->li_tv.vval.v_string = NULL;
4509 	}
4510 	generate_NEWLIST(cctx, l->lv_len);
4511 	type = &t_list_string;
4512 	member_type = &t_list_string;
4513 	list_free(l);
4514 	p += STRLEN(p);
4515 	end = p;
4516     }
4517     else if (var_count > 0)
4518     {
4519 	// for "[var, var] = expr" evaluate the expression here, loop over the
4520 	// list of variables below.
4521 
4522 	p = skipwhite(op + oplen);
4523 	if (compile_expr0(&p, cctx) == FAIL)
4524 	    return NULL;
4525 	end = p;
4526 
4527 	if (cctx->ctx_skip != SKIP_YES)
4528 	{
4529 	    type_T	*stacktype;
4530 
4531 	    stacktype = stack->ga_len == 0 ? &t_void
4532 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
4533 	    if (stacktype->tt_type == VAR_VOID)
4534 	    {
4535 		emsg(_(e_cannot_use_void_value));
4536 		goto theend;
4537 	    }
4538 	    if (need_type(stacktype, &t_list_any, -1, cctx, FALSE) == FAIL)
4539 		goto theend;
4540 	    // TODO: check the length of a constant list here
4541 	    generate_CHECKLEN(cctx, semicolon ? var_count - 1 : var_count,
4542 								    semicolon);
4543 	}
4544     }
4545 
4546     /*
4547      * Loop over variables in "[var, var] = expr".
4548      * For "var = expr" and "let var: type" this is done only once.
4549      */
4550     if (var_count > 0)
4551 	var_start = skipwhite(arg + 1);  // skip over the "["
4552     else
4553 	var_start = arg;
4554     for (var_idx = 0; var_idx == 0 || var_idx < var_count; var_idx++)
4555     {
4556 	char_u		*var_end = skip_var_one(var_start, FALSE);
4557 	size_t		varlen;
4558 	int		new_local = FALSE;
4559 	int		opt_type;
4560 	int		opt_flags = 0;
4561 	assign_dest_T	dest = dest_local;
4562 	int		vimvaridx = -1;
4563 	lvar_T		*lvar = NULL;
4564 	lvar_T		arg_lvar;
4565 	int		has_type = FALSE;
4566 	int		has_index = FALSE;
4567 	int		instr_count = -1;
4568 
4569 	if (*var_start == '@')
4570 	    p = var_start + 2;
4571 	else
4572 	{
4573 	    // skip over the leading "&", "&l:", "&g:" and "$"
4574 	    p = skip_option_env_lead(var_start);
4575 	    p = to_name_end(p, TRUE);
4576 	}
4577 
4578 	// "a: type" is declaring variable "a" with a type, not "a:".
4579 	if (is_decl && var_end == var_start + 2 && var_end[-1] == ':')
4580 	    --var_end;
4581 	if (is_decl && p == var_start + 2 && p[-1] == ':')
4582 	    --p;
4583 
4584 	varlen = p - var_start;
4585 	vim_free(name);
4586 	name = vim_strnsave(var_start, varlen);
4587 	if (name == NULL)
4588 	    return NULL;
4589 	if (!heredoc)
4590 	    type = &t_any;
4591 
4592 	if (cctx->ctx_skip != SKIP_YES)
4593 	{
4594 	    int	    declare_error = FALSE;
4595 
4596 	    if (*var_start == '&')
4597 	    {
4598 		int	    cc;
4599 		long	    numval;
4600 
4601 		dest = dest_option;
4602 		if (cmdidx == CMD_const)
4603 		{
4604 		    emsg(_(e_const_option));
4605 		    goto theend;
4606 		}
4607 		declare_error = is_decl;
4608 		p = var_start;
4609 		p = find_option_end(&p, &opt_flags);
4610 		if (p == NULL)
4611 		{
4612 		    // cannot happen?
4613 		    emsg(_(e_letunexp));
4614 		    goto theend;
4615 		}
4616 		cc = *p;
4617 		*p = NUL;
4618 		opt_type = get_option_value(skip_option_env_lead(var_start),
4619 						     &numval, NULL, opt_flags);
4620 		*p = cc;
4621 		if (opt_type == -3)
4622 		{
4623 		    semsg(_(e_unknown_option), var_start);
4624 		    goto theend;
4625 		}
4626 		if (opt_type == -2 || opt_type == 0)
4627 		    type = &t_string;
4628 		else
4629 		    type = &t_number;	// both number and boolean option
4630 	    }
4631 	    else if (*var_start == '$')
4632 	    {
4633 		dest = dest_env;
4634 		type = &t_string;
4635 		declare_error = is_decl;
4636 	    }
4637 	    else if (*var_start == '@')
4638 	    {
4639 		if (!valid_yank_reg(var_start[1], FALSE) || var_start[1] == '.')
4640 		{
4641 		    emsg_invreg(var_start[1]);
4642 		    goto theend;
4643 		}
4644 		dest = dest_reg;
4645 		type = &t_string;
4646 		declare_error = is_decl;
4647 	    }
4648 	    else if (varlen > 1 && STRNCMP(var_start, "g:", 2) == 0)
4649 	    {
4650 		dest = dest_global;
4651 		declare_error = is_decl;
4652 	    }
4653 	    else if (varlen > 1 && STRNCMP(var_start, "b:", 2) == 0)
4654 	    {
4655 		dest = dest_buffer;
4656 		declare_error = is_decl;
4657 	    }
4658 	    else if (varlen > 1 && STRNCMP(var_start, "w:", 2) == 0)
4659 	    {
4660 		dest = dest_window;
4661 		declare_error = is_decl;
4662 	    }
4663 	    else if (varlen > 1 && STRNCMP(var_start, "t:", 2) == 0)
4664 	    {
4665 		dest = dest_tab;
4666 		declare_error = is_decl;
4667 	    }
4668 	    else if (varlen > 1 && STRNCMP(var_start, "v:", 2) == 0)
4669 	    {
4670 		typval_T	*vtv;
4671 		int		di_flags;
4672 
4673 		vimvaridx = find_vim_var(name + 2, &di_flags);
4674 		if (vimvaridx < 0)
4675 		{
4676 		    semsg(_(e_variable_not_found_str), var_start);
4677 		    goto theend;
4678 		}
4679 		// We use the current value of "sandbox" here, is that OK?
4680 		if (var_check_ro(di_flags, name, FALSE))
4681 		    goto theend;
4682 		dest = dest_vimvar;
4683 		vtv = get_vim_var_tv(vimvaridx);
4684 		type = typval2type_vimvar(vtv, cctx->ctx_type_list);
4685 		declare_error = is_decl;
4686 	    }
4687 	    else
4688 	    {
4689 		int	    idx;
4690 
4691 		for (idx = 0; reserved[idx] != NULL; ++idx)
4692 		    if (STRCMP(reserved[idx], name) == 0)
4693 		    {
4694 			semsg(_(e_cannot_use_reserved_name), name);
4695 			goto theend;
4696 		    }
4697 
4698 		lvar = lookup_local(var_start, varlen, cctx);
4699 		if (lvar == NULL)
4700 		{
4701 		    CLEAR_FIELD(arg_lvar);
4702 		    if (lookup_arg(var_start, varlen,
4703 				&arg_lvar.lv_idx, &arg_lvar.lv_type,
4704 				&arg_lvar.lv_from_outer, cctx) == OK)
4705 		    {
4706 			if (is_decl)
4707 			{
4708 			    semsg(_(e_str_is_used_as_argument), name);
4709 			    goto theend;
4710 			}
4711 			lvar = &arg_lvar;
4712 		    }
4713 		}
4714 		if (lvar != NULL)
4715 		{
4716 		    if (is_decl)
4717 		    {
4718 			semsg(_(e_variable_already_declared), name);
4719 			goto theend;
4720 		    }
4721 		    else if (lvar->lv_const)
4722 		    {
4723 			semsg(_(e_cannot_assign_to_constant), name);
4724 			goto theend;
4725 		    }
4726 		}
4727 		else
4728 		{
4729 		    int script_namespace = varlen > 1
4730 					   && STRNCMP(var_start, "s:", 2) == 0;
4731 		    int script_var = (script_namespace
4732 			      ? lookup_script(var_start + 2, varlen - 2, FALSE)
4733 			      : lookup_script(var_start, varlen, TRUE)) == OK;
4734 		    imported_T  *import =
4735 					find_imported(var_start, varlen, cctx);
4736 
4737 		    if (script_namespace || script_var || import != NULL)
4738 		    {
4739 			char_u	*rawname = name + (name[1] == ':' ? 2 : 0);
4740 
4741 			if (is_decl)
4742 			{
4743 			    if (script_namespace)
4744 				semsg(_(e_cannot_declare_script_variable_in_function),
4745 									 name);
4746 			    else
4747 				semsg(_(e_variable_already_declared_in_script),
4748 									 name);
4749 			    goto theend;
4750 			}
4751 			else if (cctx->ctx_ufunc->uf_script_ctx_version
4752 							== SCRIPT_VERSION_VIM9
4753 				&& script_namespace
4754 					      && !script_var && import == NULL)
4755 			{
4756 			    semsg(_(e_unknown_variable_str), name);
4757 			    goto theend;
4758 			}
4759 
4760 			dest = dest_script;
4761 
4762 			// existing script-local variables should have a type
4763 			scriptvar_sid = current_sctx.sc_sid;
4764 			if (import != NULL)
4765 			    scriptvar_sid = import->imp_sid;
4766 			if (SCRIPT_ID_VALID(scriptvar_sid))
4767 			{
4768 			    scriptvar_idx = get_script_item_idx(scriptvar_sid,
4769 								rawname, TRUE);
4770 			    if (scriptvar_idx > 0)
4771 			    {
4772 				scriptitem_T *si = SCRIPT_ITEM(scriptvar_sid);
4773 				svar_T	     *sv =
4774 					    ((svar_T *)si->sn_var_vals.ga_data)
4775 							       + scriptvar_idx;
4776 				type = sv->sv_type;
4777 			    }
4778 			}
4779 		    }
4780 		    else if (name[1] == ':' && name[2] != NUL)
4781 		    {
4782 			semsg(_(e_cannot_use_namespaced_variable), name);
4783 			goto theend;
4784 		    }
4785 		    else if (!is_decl)
4786 		    {
4787 			semsg(_(e_unknown_variable_str), name);
4788 			goto theend;
4789 		    }
4790 		    else if (check_defined(var_start, varlen, cctx) == FAIL)
4791 			goto theend;
4792 		}
4793 	    }
4794 
4795 	    if (declare_error)
4796 	    {
4797 		vim9_declare_error(name);
4798 		goto theend;
4799 	    }
4800 	}
4801 
4802 	// handle "a:name" as a name, not index "name" on "a"
4803 	if (varlen > 1 || var_start[varlen] != ':')
4804 	    p = var_end;
4805 
4806 	if (dest != dest_option)
4807 	{
4808 	    if (is_decl && *p == ':')
4809 	    {
4810 		// parse optional type: "let var: type = expr"
4811 		if (!VIM_ISWHITE(p[1]))
4812 		{
4813 		    semsg(_(e_white_space_required_after_str), ":");
4814 		    goto theend;
4815 		}
4816 		p = skipwhite(p + 1);
4817 		type = parse_type(&p, cctx->ctx_type_list);
4818 		has_type = TRUE;
4819 	    }
4820 	    else if (lvar != NULL)
4821 		type = lvar->lv_type;
4822 	}
4823 
4824 	if (oplen == 3 && !heredoc && dest != dest_global
4825 			&& type->tt_type != VAR_STRING
4826 			&& type->tt_type != VAR_ANY)
4827 	{
4828 	    emsg(_(e_can_only_concatenate_to_string));
4829 	    goto theend;
4830 	}
4831 
4832 	if (lvar == NULL && dest == dest_local && cctx->ctx_skip != SKIP_YES)
4833 	{
4834 	    if (oplen > 1 && !heredoc)
4835 	    {
4836 		// +=, /=, etc. require an existing variable
4837 		semsg(_(e_cannot_use_operator_on_new_variable), name);
4838 		goto theend;
4839 	    }
4840 
4841 	    // new local variable
4842 	    if ((type->tt_type == VAR_FUNC || type->tt_type == VAR_PARTIAL)
4843 					    && var_wrong_func_name(name, TRUE))
4844 		goto theend;
4845 	    lvar = reserve_local(cctx, var_start, varlen,
4846 						    cmdidx == CMD_const, type);
4847 	    if (lvar == NULL)
4848 		goto theend;
4849 	    new_local = TRUE;
4850 	}
4851 
4852 	member_type = type;
4853 	if (var_end > var_start + varlen)
4854 	{
4855 	    // Something follows after the variable: "var[idx]".
4856 	    if (is_decl)
4857 	    {
4858 		emsg(_(e_cannot_use_index_when_declaring_variable));
4859 		goto theend;
4860 	    }
4861 
4862 	    if (var_start[varlen] == '[')
4863 	    {
4864 		has_index = TRUE;
4865 		if (type->tt_member == NULL)
4866 		    member_type = &t_any;
4867 		else
4868 		    member_type = type->tt_member;
4869 	    }
4870 	    else
4871 	    {
4872 		semsg("Not supported yet: %s", var_start);
4873 		goto theend;
4874 	    }
4875 	}
4876 	else if (lvar == &arg_lvar)
4877 	{
4878 	    semsg(_(e_cannot_assign_to_argument), name);
4879 	    goto theend;
4880 	}
4881 
4882 	if (!heredoc)
4883 	{
4884 	    if (cctx->ctx_skip == SKIP_YES)
4885 	    {
4886 		if (oplen > 0 && var_count == 0)
4887 		{
4888 		    // skip over the "=" and the expression
4889 		    p = skipwhite(op + oplen);
4890 		    compile_expr0(&p, cctx);
4891 		}
4892 	    }
4893 	    else if (oplen > 0)
4894 	    {
4895 		type_T	*stacktype;
4896 
4897 		// For "var = expr" evaluate the expression.
4898 		if (var_count == 0)
4899 		{
4900 		    int	r;
4901 
4902 		    // for "+=", "*=", "..=" etc. first load the current value
4903 		    if (*op != '=')
4904 		    {
4905 			generate_loadvar(cctx, dest, name, lvar, type);
4906 
4907 			if (has_index)
4908 			{
4909 			    // TODO: get member from list or dict
4910 			    emsg("Index with operation not supported yet");
4911 			    goto theend;
4912 			}
4913 		    }
4914 
4915 		    // Compile the expression.  Temporarily hide the new local
4916 		    // variable here, it is not available to this expression.
4917 		    if (new_local)
4918 			--cctx->ctx_locals.ga_len;
4919 		    instr_count = instr->ga_len;
4920 		    p = skipwhite(op + oplen);
4921 		    r = compile_expr0(&p, cctx);
4922 		    if (new_local)
4923 			++cctx->ctx_locals.ga_len;
4924 		    if (r == FAIL)
4925 			goto theend;
4926 		}
4927 		else if (semicolon && var_idx == var_count - 1)
4928 		{
4929 		    // For "[var; var] = expr" get the rest of the list
4930 		    if (generate_SLICE(cctx, var_count - 1) == FAIL)
4931 			goto theend;
4932 		}
4933 		else
4934 		{
4935 		    // For "[var, var] = expr" get the "var_idx" item from the
4936 		    // list.
4937 		    if (generate_GETITEM(cctx, var_idx) == FAIL)
4938 			return FAIL;
4939 		}
4940 
4941 		stacktype = stack->ga_len == 0 ? &t_void
4942 			      : ((type_T **)stack->ga_data)[stack->ga_len - 1];
4943 		if (lvar != NULL && (is_decl || !has_type))
4944 		{
4945 		    if (new_local && !has_type)
4946 		    {
4947 			if (stacktype->tt_type == VAR_VOID)
4948 			{
4949 			    emsg(_(e_cannot_use_void_value));
4950 			    goto theend;
4951 			}
4952 			else if ((stacktype->tt_type == VAR_FUNC
4953 				    || stacktype->tt_type == VAR_PARTIAL)
4954 					    && var_wrong_func_name(name, TRUE))
4955 			{
4956 			    goto theend;
4957 			}
4958 			else
4959 			{
4960 			    // An empty list or dict has a &t_void member,
4961 			    // for a variable that implies &t_any.
4962 			    if (stacktype == &t_list_empty)
4963 				lvar->lv_type = &t_list_any;
4964 			    else if (stacktype == &t_dict_empty)
4965 				lvar->lv_type = &t_dict_any;
4966 			    else
4967 				lvar->lv_type = stacktype;
4968 			}
4969 		    }
4970 		    else if (*op == '=')
4971 		    {
4972 			type_T *use_type = lvar->lv_type;
4973 
4974 			// without operator type is here, otherwise below
4975 			if (has_index)
4976 			{
4977 			    use_type = use_type->tt_member;
4978 			    if (use_type == NULL)
4979 				use_type = &t_void;
4980 			}
4981 			if (need_type(stacktype, use_type, -1, cctx, FALSE)
4982 								       == FAIL)
4983 			    goto theend;
4984 		    }
4985 		}
4986 		else if (*p != '=' && need_type(stacktype, member_type, -1,
4987 							  cctx, FALSE) == FAIL)
4988 		    goto theend;
4989 	    }
4990 	    else if (cmdidx == CMD_const)
4991 	    {
4992 		emsg(_(e_const_requires_a_value));
4993 		goto theend;
4994 	    }
4995 	    else if (!has_type || dest == dest_option)
4996 	    {
4997 		emsg(_(e_type_or_initialization_required));
4998 		goto theend;
4999 	    }
5000 	    else
5001 	    {
5002 		// variables are always initialized
5003 		if (ga_grow(instr, 1) == FAIL)
5004 		    goto theend;
5005 		switch (member_type->tt_type)
5006 		{
5007 		    case VAR_BOOL:
5008 			generate_PUSHBOOL(cctx, VVAL_FALSE);
5009 			break;
5010 		    case VAR_FLOAT:
5011 #ifdef FEAT_FLOAT
5012 			generate_PUSHF(cctx, 0.0);
5013 #endif
5014 			break;
5015 		    case VAR_STRING:
5016 			generate_PUSHS(cctx, NULL);
5017 			break;
5018 		    case VAR_BLOB:
5019 			generate_PUSHBLOB(cctx, NULL);
5020 			break;
5021 		    case VAR_FUNC:
5022 			generate_PUSHFUNC(cctx, NULL, &t_func_void);
5023 			break;
5024 		    case VAR_LIST:
5025 			generate_NEWLIST(cctx, 0);
5026 			break;
5027 		    case VAR_DICT:
5028 			generate_NEWDICT(cctx, 0);
5029 			break;
5030 		    case VAR_JOB:
5031 			generate_PUSHJOB(cctx, NULL);
5032 			break;
5033 		    case VAR_CHANNEL:
5034 			generate_PUSHCHANNEL(cctx, NULL);
5035 			break;
5036 		    case VAR_NUMBER:
5037 		    case VAR_UNKNOWN:
5038 		    case VAR_ANY:
5039 		    case VAR_PARTIAL:
5040 		    case VAR_VOID:
5041 		    case VAR_SPECIAL:  // cannot happen
5042 			generate_PUSHNR(cctx, 0);
5043 			break;
5044 		}
5045 	    }
5046 	    if (var_count == 0)
5047 		end = p;
5048 	}
5049 
5050 	// no need to parse more when skipping
5051 	if (cctx->ctx_skip == SKIP_YES)
5052 	    break;
5053 
5054 	if (oplen > 0 && *op != '=')
5055 	{
5056 	    type_T	    *expected;
5057 	    type_T	    *stacktype;
5058 
5059 	    if (*op == '.')
5060 		expected = &t_string;
5061 	    else
5062 		expected = member_type;
5063 	    stacktype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
5064 	    if (
5065 #ifdef FEAT_FLOAT
5066 		// If variable is float operation with number is OK.
5067 		!(expected == &t_float && stacktype == &t_number) &&
5068 #endif
5069 		    need_type(stacktype, expected, -1, cctx, FALSE) == FAIL)
5070 		goto theend;
5071 
5072 	    if (*op == '.')
5073 	    {
5074 		if (generate_instr_drop(cctx, ISN_CONCAT, 1) == NULL)
5075 		    goto theend;
5076 	    }
5077 	    else if (*op == '+')
5078 	    {
5079 		if (generate_add_instr(cctx,
5080 			    operator_type(member_type, stacktype),
5081 					       member_type, stacktype) == FAIL)
5082 		    goto theend;
5083 	    }
5084 	    else if (generate_two_op(cctx, op) == FAIL)
5085 		goto theend;
5086 	}
5087 
5088 	if (has_index)
5089 	{
5090 	    int r;
5091 
5092 	    // Compile the "idx" in "var[idx]".
5093 	    if (new_local)
5094 		--cctx->ctx_locals.ga_len;
5095 	    p = skipwhite(var_start + varlen + 1);
5096 	    r = compile_expr0(&p, cctx);
5097 	    if (new_local)
5098 		++cctx->ctx_locals.ga_len;
5099 	    if (r == FAIL)
5100 		goto theend;
5101 	    if (*skipwhite(p) != ']')
5102 	    {
5103 		// this should not happen
5104 		emsg(_(e_missbrac));
5105 		goto theend;
5106 	    }
5107 	    if (type == &t_any)
5108 	    {
5109 		type_T	    *idx_type = ((type_T **)stack->ga_data)[
5110 							    stack->ga_len - 1];
5111 		// Index on variable of unknown type: guess the type from the
5112 		// index type: number is dict, otherwise dict.
5113 		// TODO: should do the assignment at runtime
5114 		if (idx_type->tt_type == VAR_NUMBER)
5115 		    type = &t_list_any;
5116 		else
5117 		    type = &t_dict_any;
5118 	    }
5119 	    if (type->tt_type == VAR_DICT
5120 		    && may_generate_2STRING(-1, cctx) == FAIL)
5121 		goto theend;
5122 	    if (type->tt_type == VAR_LIST
5123 		    && ((type_T **)stack->ga_data)[stack->ga_len - 1]->tt_type
5124 								 != VAR_NUMBER)
5125 	    {
5126 		emsg(_(e_number_exp));
5127 		goto theend;
5128 	    }
5129 
5130 	    // Load the dict or list.  On the stack we then have:
5131 	    // - value
5132 	    // - index
5133 	    // - variable
5134 	    generate_loadvar(cctx, dest, name, lvar, type);
5135 
5136 	    if (type->tt_type == VAR_LIST)
5137 	    {
5138 		if (generate_instr_drop(cctx, ISN_STORELIST, 3) == FAIL)
5139 		    return FAIL;
5140 	    }
5141 	    else if (type->tt_type == VAR_DICT)
5142 	    {
5143 		if (generate_instr_drop(cctx, ISN_STOREDICT, 3) == FAIL)
5144 		    return FAIL;
5145 	    }
5146 	    else
5147 	    {
5148 		emsg(_(e_listreq));
5149 		goto theend;
5150 	    }
5151 	}
5152 	else
5153 	{
5154 	    switch (dest)
5155 	    {
5156 		case dest_option:
5157 		    generate_STOREOPT(cctx, skip_option_env_lead(name),
5158 								    opt_flags);
5159 		    break;
5160 		case dest_global:
5161 		    // include g: with the name, easier to execute that way
5162 		    generate_STORE(cctx, ISN_STOREG, 0, name);
5163 		    break;
5164 		case dest_buffer:
5165 		    // include b: with the name, easier to execute that way
5166 		    generate_STORE(cctx, ISN_STOREB, 0, name);
5167 		    break;
5168 		case dest_window:
5169 		    // include w: with the name, easier to execute that way
5170 		    generate_STORE(cctx, ISN_STOREW, 0, name);
5171 		    break;
5172 		case dest_tab:
5173 		    // include t: with the name, easier to execute that way
5174 		    generate_STORE(cctx, ISN_STORET, 0, name);
5175 		    break;
5176 		case dest_env:
5177 		    generate_STORE(cctx, ISN_STOREENV, 0, name + 1);
5178 		    break;
5179 		case dest_reg:
5180 		    generate_STORE(cctx, ISN_STOREREG, name[1], NULL);
5181 		    break;
5182 		case dest_vimvar:
5183 		    generate_STORE(cctx, ISN_STOREV, vimvaridx, NULL);
5184 		    break;
5185 		case dest_script:
5186 		    {
5187 			if (scriptvar_idx < 0)
5188 			{
5189 			    char_u *name_s = name;
5190 
5191 			    // Include s: in the name for store_var()
5192 			    if (name[1] != ':')
5193 			    {
5194 				int len = (int)STRLEN(name) + 3;
5195 
5196 				name_s = alloc(len);
5197 				if (name_s == NULL)
5198 				    name_s = name;
5199 				else
5200 				    vim_snprintf((char *)name_s, len,
5201 								 "s:%s", name);
5202 			    }
5203 			    generate_OLDSCRIPT(cctx, ISN_STORES, name_s,
5204 							  scriptvar_sid, type);
5205 			    if (name_s != name)
5206 				vim_free(name_s);
5207 			}
5208 			else
5209 			    generate_VIM9SCRIPT(cctx, ISN_STORESCRIPT,
5210 					   scriptvar_sid, scriptvar_idx, type);
5211 		    }
5212 		    break;
5213 		case dest_local:
5214 		    if (lvar != NULL)
5215 		    {
5216 			isn_T *isn = ((isn_T *)instr->ga_data)
5217 							   + instr->ga_len - 1;
5218 
5219 			// optimization: turn "var = 123" from ISN_PUSHNR +
5220 			// ISN_STORE into ISN_STORENR
5221 			if (!lvar->lv_from_outer
5222 					&& instr->ga_len == instr_count + 1
5223 					&& isn->isn_type == ISN_PUSHNR)
5224 			{
5225 			    varnumber_T val = isn->isn_arg.number;
5226 
5227 			    isn->isn_type = ISN_STORENR;
5228 			    isn->isn_arg.storenr.stnr_idx = lvar->lv_idx;
5229 			    isn->isn_arg.storenr.stnr_val = val;
5230 			    if (stack->ga_len > 0)
5231 				--stack->ga_len;
5232 			}
5233 			else if (lvar->lv_from_outer)
5234 			    generate_STORE(cctx, ISN_STOREOUTER, lvar->lv_idx,
5235 									 NULL);
5236 			else
5237 			    generate_STORE(cctx, ISN_STORE, lvar->lv_idx, NULL);
5238 		    }
5239 		    break;
5240 	    }
5241 	}
5242 
5243 	if (var_idx + 1 < var_count)
5244 	    var_start = skipwhite(var_end + 1);
5245     }
5246 
5247     // for "[var, var] = expr" drop the "expr" value
5248     if (var_count > 0 && !semicolon)
5249     {
5250 	    if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
5251 	    goto theend;
5252     }
5253 
5254     ret = skipwhite(end);
5255 
5256 theend:
5257     vim_free(name);
5258     return ret;
5259 }
5260 
5261 /*
5262  * Check if "name" can be "unlet".
5263  */
5264     int
5265 check_vim9_unlet(char_u *name)
5266 {
5267     if (name[1] != ':' || vim_strchr((char_u *)"gwtb", *name) == NULL)
5268     {
5269 	// "unlet s:var" is allowed in legacy script.
5270 	if (*name == 's' && !script_is_vim9())
5271 	    return OK;
5272 	semsg(_(e_cannot_unlet_str), name);
5273 	return FAIL;
5274     }
5275     return OK;
5276 }
5277 
5278 /*
5279  * Callback passed to ex_unletlock().
5280  */
5281     static int
5282 compile_unlet(
5283     lval_T  *lvp,
5284     char_u  *name_end,
5285     exarg_T *eap,
5286     int	    deep UNUSED,
5287     void    *coookie)
5288 {
5289     cctx_T *cctx = coookie;
5290 
5291     if (lvp->ll_tv == NULL)
5292     {
5293 	char_u	*p = lvp->ll_name;
5294 	int	cc = *name_end;
5295 	int	ret = OK;
5296 
5297 	// Normal name.  Only supports g:, w:, t: and b: namespaces.
5298 	*name_end = NUL;
5299 	if (*p == '$')
5300 	    ret = generate_UNLET(cctx, ISN_UNLETENV, p + 1, eap->forceit);
5301 	else if (check_vim9_unlet(p) == FAIL)
5302 	    ret = FAIL;
5303 	else
5304 	    ret = generate_UNLET(cctx, ISN_UNLET, p, eap->forceit);
5305 
5306 	*name_end = cc;
5307 	return ret;
5308     }
5309 
5310     // TODO: unlet {list}[idx]
5311     // TODO: unlet {dict}[key]
5312     emsg("Sorry, :unlet not fully implemented yet");
5313     return FAIL;
5314 }
5315 
5316 /*
5317  * compile "unlet var", "lock var" and "unlock var"
5318  * "arg" points to "var".
5319  */
5320     static char_u *
5321 compile_unletlock(char_u *arg, exarg_T *eap, cctx_T *cctx)
5322 {
5323     char_u *p = arg;
5324 
5325     if (eap->cmdidx != CMD_unlet)
5326     {
5327 	emsg("Sorry, :lock and unlock not implemented yet");
5328 	return NULL;
5329     }
5330 
5331     if (*p == '!')
5332     {
5333 	p = skipwhite(p + 1);
5334 	eap->forceit = TRUE;
5335     }
5336 
5337     ex_unletlock(eap, p, 0, GLV_NO_AUTOLOAD, compile_unlet, cctx);
5338     return eap->nextcmd == NULL ? (char_u *)"" : eap->nextcmd;
5339 }
5340 
5341 /*
5342  * Compile an :import command.
5343  */
5344     static char_u *
5345 compile_import(char_u *arg, cctx_T *cctx)
5346 {
5347     return handle_import(arg, &cctx->ctx_imports, 0, NULL, cctx);
5348 }
5349 
5350 /*
5351  * generate a jump to the ":endif"/":endfor"/":endwhile"/":finally"/":endtry".
5352  */
5353     static int
5354 compile_jump_to_end(endlabel_T **el, jumpwhen_T when, cctx_T *cctx)
5355 {
5356     garray_T	*instr = &cctx->ctx_instr;
5357     endlabel_T  *endlabel = ALLOC_CLEAR_ONE(endlabel_T);
5358 
5359     if (endlabel == NULL)
5360 	return FAIL;
5361     endlabel->el_next = *el;
5362     *el = endlabel;
5363     endlabel->el_end_label = instr->ga_len;
5364 
5365     generate_JUMP(cctx, when, 0);
5366     return OK;
5367 }
5368 
5369     static void
5370 compile_fill_jump_to_end(endlabel_T **el, cctx_T *cctx)
5371 {
5372     garray_T	*instr = &cctx->ctx_instr;
5373 
5374     while (*el != NULL)
5375     {
5376 	endlabel_T  *cur = (*el);
5377 	isn_T	    *isn;
5378 
5379 	isn = ((isn_T *)instr->ga_data) + cur->el_end_label;
5380 	isn->isn_arg.jump.jump_where = instr->ga_len;
5381 	*el = cur->el_next;
5382 	vim_free(cur);
5383     }
5384 }
5385 
5386     static void
5387 compile_free_jump_to_end(endlabel_T **el)
5388 {
5389     while (*el != NULL)
5390     {
5391 	endlabel_T  *cur = (*el);
5392 
5393 	*el = cur->el_next;
5394 	vim_free(cur);
5395     }
5396 }
5397 
5398 /*
5399  * Create a new scope and set up the generic items.
5400  */
5401     static scope_T *
5402 new_scope(cctx_T *cctx, scopetype_T type)
5403 {
5404     scope_T *scope = ALLOC_CLEAR_ONE(scope_T);
5405 
5406     if (scope == NULL)
5407 	return NULL;
5408     scope->se_outer = cctx->ctx_scope;
5409     cctx->ctx_scope = scope;
5410     scope->se_type = type;
5411     scope->se_local_count = cctx->ctx_locals.ga_len;
5412     return scope;
5413 }
5414 
5415 /*
5416  * Free the current scope and go back to the outer scope.
5417  */
5418     static void
5419 drop_scope(cctx_T *cctx)
5420 {
5421     scope_T *scope = cctx->ctx_scope;
5422 
5423     if (scope == NULL)
5424     {
5425 	iemsg("calling drop_scope() without a scope");
5426 	return;
5427     }
5428     cctx->ctx_scope = scope->se_outer;
5429     switch (scope->se_type)
5430     {
5431 	case IF_SCOPE:
5432 	    compile_free_jump_to_end(&scope->se_u.se_if.is_end_label); break;
5433 	case FOR_SCOPE:
5434 	    compile_free_jump_to_end(&scope->se_u.se_for.fs_end_label); break;
5435 	case WHILE_SCOPE:
5436 	    compile_free_jump_to_end(&scope->se_u.se_while.ws_end_label); break;
5437 	case TRY_SCOPE:
5438 	    compile_free_jump_to_end(&scope->se_u.se_try.ts_end_label); break;
5439 	case NO_SCOPE:
5440 	case BLOCK_SCOPE:
5441 	    break;
5442     }
5443     vim_free(scope);
5444 }
5445 
5446 /*
5447  * compile "if expr"
5448  *
5449  * "if expr" Produces instructions:
5450  *	EVAL expr		Push result of "expr"
5451  *	JUMP_IF_FALSE end
5452  *	... body ...
5453  * end:
5454  *
5455  * "if expr | else" Produces instructions:
5456  *	EVAL expr		Push result of "expr"
5457  *	JUMP_IF_FALSE else
5458  *	... body ...
5459  *	JUMP_ALWAYS end
5460  * else:
5461  *	... body ...
5462  * end:
5463  *
5464  * "if expr1 | elseif expr2 | else" Produces instructions:
5465  *	EVAL expr		Push result of "expr"
5466  *	JUMP_IF_FALSE elseif
5467  *	... body ...
5468  *	JUMP_ALWAYS end
5469  * elseif:
5470  *	EVAL expr		Push result of "expr"
5471  *	JUMP_IF_FALSE else
5472  *	... body ...
5473  *	JUMP_ALWAYS end
5474  * else:
5475  *	... body ...
5476  * end:
5477  */
5478     static char_u *
5479 compile_if(char_u *arg, cctx_T *cctx)
5480 {
5481     char_u	*p = arg;
5482     garray_T	*instr = &cctx->ctx_instr;
5483     int		instr_count = instr->ga_len;
5484     scope_T	*scope;
5485     skip_T	skip_save = cctx->ctx_skip;
5486     ppconst_T	ppconst;
5487 
5488     CLEAR_FIELD(ppconst);
5489     if (compile_expr1(&p, cctx, &ppconst) == FAIL)
5490     {
5491 	clear_ppconst(&ppconst);
5492 	return NULL;
5493     }
5494     if (cctx->ctx_skip == SKIP_YES)
5495 	clear_ppconst(&ppconst);
5496     else if (instr->ga_len == instr_count && ppconst.pp_used == 1)
5497     {
5498 	// The expression results in a constant.
5499 	cctx->ctx_skip = tv2bool(&ppconst.pp_tv[0]) ? SKIP_NOT : SKIP_YES;
5500 	clear_ppconst(&ppconst);
5501     }
5502     else
5503     {
5504 	// Not a constant, generate instructions for the expression.
5505 	cctx->ctx_skip = SKIP_UNKNOWN;
5506 	if (generate_ppconst(cctx, &ppconst) == FAIL)
5507 	    return NULL;
5508     }
5509 
5510     scope = new_scope(cctx, IF_SCOPE);
5511     if (scope == NULL)
5512 	return NULL;
5513     scope->se_skip_save = skip_save;
5514     // "is_had_return" will be reset if any block does not end in :return
5515     scope->se_u.se_if.is_had_return = TRUE;
5516 
5517     if (cctx->ctx_skip == SKIP_UNKNOWN)
5518     {
5519 	// "where" is set when ":elseif", "else" or ":endif" is found
5520 	scope->se_u.se_if.is_if_label = instr->ga_len;
5521 	generate_JUMP(cctx, JUMP_IF_FALSE, 0);
5522     }
5523     else
5524 	scope->se_u.se_if.is_if_label = -1;
5525 
5526     return p;
5527 }
5528 
5529     static char_u *
5530 compile_elseif(char_u *arg, cctx_T *cctx)
5531 {
5532     char_u	*p = arg;
5533     garray_T	*instr = &cctx->ctx_instr;
5534     int		instr_count = instr->ga_len;
5535     isn_T	*isn;
5536     scope_T	*scope = cctx->ctx_scope;
5537     ppconst_T	ppconst;
5538     skip_T	save_skip = cctx->ctx_skip;
5539 
5540     if (scope == NULL || scope->se_type != IF_SCOPE)
5541     {
5542 	emsg(_(e_elseif_without_if));
5543 	return NULL;
5544     }
5545     unwind_locals(cctx, scope->se_local_count);
5546     if (!cctx->ctx_had_return)
5547 	scope->se_u.se_if.is_had_return = FALSE;
5548 
5549     if (cctx->ctx_skip == SKIP_UNKNOWN)
5550     {
5551 	if (compile_jump_to_end(&scope->se_u.se_if.is_end_label,
5552 						    JUMP_ALWAYS, cctx) == FAIL)
5553 	    return NULL;
5554 	// previous "if" or "elseif" jumps here
5555 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
5556 	isn->isn_arg.jump.jump_where = instr->ga_len;
5557     }
5558 
5559     // compile "expr"; if we know it evaluates to FALSE skip the block
5560     CLEAR_FIELD(ppconst);
5561     if (cctx->ctx_skip == SKIP_YES)
5562 	cctx->ctx_skip = SKIP_UNKNOWN;
5563     if (compile_expr1(&p, cctx, &ppconst) == FAIL)
5564     {
5565 	clear_ppconst(&ppconst);
5566 	return NULL;
5567     }
5568     cctx->ctx_skip = save_skip;
5569     if (scope->se_skip_save == SKIP_YES)
5570 	clear_ppconst(&ppconst);
5571     else if (instr->ga_len == instr_count && ppconst.pp_used == 1)
5572     {
5573 	// The expression results in a constant.
5574 	// TODO: how about nesting?
5575 	cctx->ctx_skip = tv2bool(&ppconst.pp_tv[0]) ? SKIP_NOT : SKIP_YES;
5576 	clear_ppconst(&ppconst);
5577 	scope->se_u.se_if.is_if_label = -1;
5578     }
5579     else
5580     {
5581 	// Not a constant, generate instructions for the expression.
5582 	cctx->ctx_skip = SKIP_UNKNOWN;
5583 	if (generate_ppconst(cctx, &ppconst) == FAIL)
5584 	    return NULL;
5585 
5586 	// "where" is set when ":elseif", "else" or ":endif" is found
5587 	scope->se_u.se_if.is_if_label = instr->ga_len;
5588 	generate_JUMP(cctx, JUMP_IF_FALSE, 0);
5589     }
5590 
5591     return p;
5592 }
5593 
5594     static char_u *
5595 compile_else(char_u *arg, cctx_T *cctx)
5596 {
5597     char_u	*p = arg;
5598     garray_T	*instr = &cctx->ctx_instr;
5599     isn_T	*isn;
5600     scope_T	*scope = cctx->ctx_scope;
5601 
5602     if (scope == NULL || scope->se_type != IF_SCOPE)
5603     {
5604 	emsg(_(e_else_without_if));
5605 	return NULL;
5606     }
5607     unwind_locals(cctx, scope->se_local_count);
5608     if (!cctx->ctx_had_return)
5609 	scope->se_u.se_if.is_had_return = FALSE;
5610     scope->se_u.se_if.is_seen_else = TRUE;
5611 
5612     if (scope->se_skip_save != SKIP_YES)
5613     {
5614 	// jump from previous block to the end, unless the else block is empty
5615 	if (cctx->ctx_skip == SKIP_UNKNOWN)
5616 	{
5617 	    if (!cctx->ctx_had_return
5618 		    && compile_jump_to_end(&scope->se_u.se_if.is_end_label,
5619 						    JUMP_ALWAYS, cctx) == FAIL)
5620 		return NULL;
5621 	}
5622 
5623 	if (cctx->ctx_skip == SKIP_UNKNOWN)
5624 	{
5625 	    if (scope->se_u.se_if.is_if_label >= 0)
5626 	    {
5627 		// previous "if" or "elseif" jumps here
5628 		isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
5629 		isn->isn_arg.jump.jump_where = instr->ga_len;
5630 		scope->se_u.se_if.is_if_label = -1;
5631 	    }
5632 	}
5633 
5634 	if (cctx->ctx_skip != SKIP_UNKNOWN)
5635 	    cctx->ctx_skip = cctx->ctx_skip == SKIP_YES ? SKIP_NOT : SKIP_YES;
5636     }
5637 
5638     return p;
5639 }
5640 
5641     static char_u *
5642 compile_endif(char_u *arg, cctx_T *cctx)
5643 {
5644     scope_T	*scope = cctx->ctx_scope;
5645     ifscope_T	*ifscope;
5646     garray_T	*instr = &cctx->ctx_instr;
5647     isn_T	*isn;
5648 
5649     if (scope == NULL || scope->se_type != IF_SCOPE)
5650     {
5651 	emsg(_(e_endif_without_if));
5652 	return NULL;
5653     }
5654     ifscope = &scope->se_u.se_if;
5655     unwind_locals(cctx, scope->se_local_count);
5656     if (!cctx->ctx_had_return)
5657 	ifscope->is_had_return = FALSE;
5658 
5659     if (scope->se_u.se_if.is_if_label >= 0)
5660     {
5661 	// previous "if" or "elseif" jumps here
5662 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_if.is_if_label;
5663 	isn->isn_arg.jump.jump_where = instr->ga_len;
5664     }
5665     // Fill in the "end" label in jumps at the end of the blocks.
5666     compile_fill_jump_to_end(&ifscope->is_end_label, cctx);
5667     cctx->ctx_skip = scope->se_skip_save;
5668 
5669     // If all the blocks end in :return and there is an :else then the
5670     // had_return flag is set.
5671     cctx->ctx_had_return = ifscope->is_had_return && ifscope->is_seen_else;
5672 
5673     drop_scope(cctx);
5674     return arg;
5675 }
5676 
5677 /*
5678  * compile "for var in expr"
5679  *
5680  * Produces instructions:
5681  *       PUSHNR -1
5682  *       STORE loop-idx		Set index to -1
5683  *       EVAL expr		Push result of "expr"
5684  * top:  FOR loop-idx, end	Increment index, use list on bottom of stack
5685  *				- if beyond end, jump to "end"
5686  *				- otherwise get item from list and push it
5687  *       STORE var		Store item in "var"
5688  *       ... body ...
5689  *       JUMP top		Jump back to repeat
5690  * end:	 DROP			Drop the result of "expr"
5691  *
5692  */
5693     static char_u *
5694 compile_for(char_u *arg, cctx_T *cctx)
5695 {
5696     char_u	*p;
5697     size_t	varlen;
5698     garray_T	*instr = &cctx->ctx_instr;
5699     garray_T	*stack = &cctx->ctx_type_stack;
5700     scope_T	*scope;
5701     lvar_T	*loop_lvar;	// loop iteration variable
5702     lvar_T	*var_lvar;	// variable for "var"
5703     type_T	*vartype;
5704 
5705     // TODO: list of variables: "for [key, value] in dict"
5706     // parse "var"
5707     for (p = arg; eval_isnamec1(*p); ++p)
5708 	;
5709     varlen = p - arg;
5710     var_lvar = lookup_local(arg, varlen, cctx);
5711     if (var_lvar != NULL)
5712     {
5713 	semsg(_(e_variable_already_declared), arg);
5714 	return NULL;
5715     }
5716 
5717     // consume "in"
5718     p = skipwhite(p);
5719     if (STRNCMP(p, "in", 2) != 0 || !VIM_ISWHITE(p[2]))
5720     {
5721 	emsg(_(e_missing_in));
5722 	return NULL;
5723     }
5724     p = skipwhite(p + 2);
5725 
5726 
5727     scope = new_scope(cctx, FOR_SCOPE);
5728     if (scope == NULL)
5729 	return NULL;
5730 
5731     // Reserve a variable to store the loop iteration counter.
5732     loop_lvar = reserve_local(cctx, (char_u *)"", 0, FALSE, &t_number);
5733     if (loop_lvar == NULL)
5734     {
5735 	// out of memory
5736 	drop_scope(cctx);
5737 	return NULL;
5738     }
5739 
5740     // Reserve a variable to store "var"
5741     var_lvar = reserve_local(cctx, arg, varlen, FALSE, &t_any);
5742     if (var_lvar == NULL)
5743     {
5744 	// out of memory or used as an argument
5745 	drop_scope(cctx);
5746 	return NULL;
5747     }
5748 
5749     generate_STORENR(cctx, loop_lvar->lv_idx, -1);
5750 
5751     // compile "expr", it remains on the stack until "endfor"
5752     arg = p;
5753     if (compile_expr0(&arg, cctx) == FAIL)
5754     {
5755 	drop_scope(cctx);
5756 	return NULL;
5757     }
5758 
5759     // Now that we know the type of "var", check that it is a list, now or at
5760     // runtime.
5761     vartype = ((type_T **)stack->ga_data)[stack->ga_len - 1];
5762     if (need_type(vartype, &t_list_any, -1, cctx, FALSE) == FAIL)
5763     {
5764 	drop_scope(cctx);
5765 	return NULL;
5766     }
5767     if (vartype->tt_type == VAR_LIST && vartype->tt_member->tt_type != VAR_ANY)
5768 	var_lvar->lv_type = vartype->tt_member;
5769 
5770     // "for_end" is set when ":endfor" is found
5771     scope->se_u.se_for.fs_top_label = instr->ga_len;
5772 
5773     generate_FOR(cctx, loop_lvar->lv_idx);
5774     generate_STORE(cctx, ISN_STORE, var_lvar->lv_idx, NULL);
5775 
5776     return arg;
5777 }
5778 
5779 /*
5780  * compile "endfor"
5781  */
5782     static char_u *
5783 compile_endfor(char_u *arg, cctx_T *cctx)
5784 {
5785     garray_T	*instr = &cctx->ctx_instr;
5786     scope_T	*scope = cctx->ctx_scope;
5787     forscope_T	*forscope;
5788     isn_T	*isn;
5789 
5790     if (scope == NULL || scope->se_type != FOR_SCOPE)
5791     {
5792 	emsg(_(e_for));
5793 	return NULL;
5794     }
5795     forscope = &scope->se_u.se_for;
5796     cctx->ctx_scope = scope->se_outer;
5797     unwind_locals(cctx, scope->se_local_count);
5798 
5799     // At end of ":for" scope jump back to the FOR instruction.
5800     generate_JUMP(cctx, JUMP_ALWAYS, forscope->fs_top_label);
5801 
5802     // Fill in the "end" label in the FOR statement so it can jump here
5803     isn = ((isn_T *)instr->ga_data) + forscope->fs_top_label;
5804     isn->isn_arg.forloop.for_end = instr->ga_len;
5805 
5806     // Fill in the "end" label any BREAK statements
5807     compile_fill_jump_to_end(&forscope->fs_end_label, cctx);
5808 
5809     // Below the ":for" scope drop the "expr" list from the stack.
5810     if (generate_instr_drop(cctx, ISN_DROP, 1) == NULL)
5811 	return NULL;
5812 
5813     vim_free(scope);
5814 
5815     return arg;
5816 }
5817 
5818 /*
5819  * compile "while expr"
5820  *
5821  * Produces instructions:
5822  * top:  EVAL expr		Push result of "expr"
5823  *       JUMP_IF_FALSE end	jump if false
5824  *       ... body ...
5825  *       JUMP top		Jump back to repeat
5826  * end:
5827  *
5828  */
5829     static char_u *
5830 compile_while(char_u *arg, cctx_T *cctx)
5831 {
5832     char_u	*p = arg;
5833     garray_T	*instr = &cctx->ctx_instr;
5834     scope_T	*scope;
5835 
5836     scope = new_scope(cctx, WHILE_SCOPE);
5837     if (scope == NULL)
5838 	return NULL;
5839 
5840     scope->se_u.se_while.ws_top_label = instr->ga_len;
5841 
5842     // compile "expr"
5843     if (compile_expr0(&p, cctx) == FAIL)
5844 	return NULL;
5845 
5846     // "while_end" is set when ":endwhile" is found
5847     if (compile_jump_to_end(&scope->se_u.se_while.ws_end_label,
5848 						  JUMP_IF_FALSE, cctx) == FAIL)
5849 	return FAIL;
5850 
5851     return p;
5852 }
5853 
5854 /*
5855  * compile "endwhile"
5856  */
5857     static char_u *
5858 compile_endwhile(char_u *arg, cctx_T *cctx)
5859 {
5860     scope_T	*scope = cctx->ctx_scope;
5861 
5862     if (scope == NULL || scope->se_type != WHILE_SCOPE)
5863     {
5864 	emsg(_(e_while));
5865 	return NULL;
5866     }
5867     cctx->ctx_scope = scope->se_outer;
5868     unwind_locals(cctx, scope->se_local_count);
5869 
5870     // At end of ":for" scope jump back to the FOR instruction.
5871     generate_JUMP(cctx, JUMP_ALWAYS, scope->se_u.se_while.ws_top_label);
5872 
5873     // Fill in the "end" label in the WHILE statement so it can jump here.
5874     // And in any jumps for ":break"
5875     compile_fill_jump_to_end(&scope->se_u.se_while.ws_end_label, cctx);
5876 
5877     vim_free(scope);
5878 
5879     return arg;
5880 }
5881 
5882 /*
5883  * compile "continue"
5884  */
5885     static char_u *
5886 compile_continue(char_u *arg, cctx_T *cctx)
5887 {
5888     scope_T	*scope = cctx->ctx_scope;
5889 
5890     for (;;)
5891     {
5892 	if (scope == NULL)
5893 	{
5894 	    emsg(_(e_continue));
5895 	    return NULL;
5896 	}
5897 	if (scope->se_type == FOR_SCOPE || scope->se_type == WHILE_SCOPE)
5898 	    break;
5899 	scope = scope->se_outer;
5900     }
5901 
5902     // Jump back to the FOR or WHILE instruction.
5903     generate_JUMP(cctx, JUMP_ALWAYS,
5904 	    scope->se_type == FOR_SCOPE ? scope->se_u.se_for.fs_top_label
5905 					  : scope->se_u.se_while.ws_top_label);
5906     return arg;
5907 }
5908 
5909 /*
5910  * compile "break"
5911  */
5912     static char_u *
5913 compile_break(char_u *arg, cctx_T *cctx)
5914 {
5915     scope_T	*scope = cctx->ctx_scope;
5916     endlabel_T	**el;
5917 
5918     for (;;)
5919     {
5920 	if (scope == NULL)
5921 	{
5922 	    emsg(_(e_break));
5923 	    return NULL;
5924 	}
5925 	if (scope->se_type == FOR_SCOPE || scope->se_type == WHILE_SCOPE)
5926 	    break;
5927 	scope = scope->se_outer;
5928     }
5929 
5930     // Jump to the end of the FOR or WHILE loop.
5931     if (scope->se_type == FOR_SCOPE)
5932 	el = &scope->se_u.se_for.fs_end_label;
5933     else
5934 	el = &scope->se_u.se_while.ws_end_label;
5935     if (compile_jump_to_end(el, JUMP_ALWAYS, cctx) == FAIL)
5936 	return FAIL;
5937 
5938     return arg;
5939 }
5940 
5941 /*
5942  * compile "{" start of block
5943  */
5944     static char_u *
5945 compile_block(char_u *arg, cctx_T *cctx)
5946 {
5947     if (new_scope(cctx, BLOCK_SCOPE) == NULL)
5948 	return NULL;
5949     return skipwhite(arg + 1);
5950 }
5951 
5952 /*
5953  * compile end of block: drop one scope
5954  */
5955     static void
5956 compile_endblock(cctx_T *cctx)
5957 {
5958     scope_T	*scope = cctx->ctx_scope;
5959 
5960     cctx->ctx_scope = scope->se_outer;
5961     unwind_locals(cctx, scope->se_local_count);
5962     vim_free(scope);
5963 }
5964 
5965 /*
5966  * compile "try"
5967  * Creates a new scope for the try-endtry, pointing to the first catch and
5968  * finally.
5969  * Creates another scope for the "try" block itself.
5970  * TRY instruction sets up exception handling at runtime.
5971  *
5972  *	"try"
5973  *	    TRY -> catch1, -> finally  push trystack entry
5974  *	    ... try block
5975  *	"throw {exception}"
5976  *	    EVAL {exception}
5977  *	    THROW		create exception
5978  *	    ... try block
5979  *	" catch {expr}"
5980  *	    JUMP -> finally
5981  * catch1:  PUSH exeception
5982  *	    EVAL {expr}
5983  *	    MATCH
5984  *	    JUMP nomatch -> catch2
5985  *	    CATCH   remove exception
5986  *	    ... catch block
5987  *	" catch"
5988  *	    JUMP -> finally
5989  * catch2:  CATCH   remove exception
5990  *	    ... catch block
5991  *	" finally"
5992  * finally:
5993  *	    ... finally block
5994  *	" endtry"
5995  *	    ENDTRY  pop trystack entry, may rethrow
5996  */
5997     static char_u *
5998 compile_try(char_u *arg, cctx_T *cctx)
5999 {
6000     garray_T	*instr = &cctx->ctx_instr;
6001     scope_T	*try_scope;
6002     scope_T	*scope;
6003 
6004     // scope that holds the jumps that go to catch/finally/endtry
6005     try_scope = new_scope(cctx, TRY_SCOPE);
6006     if (try_scope == NULL)
6007 	return NULL;
6008 
6009     // "catch" is set when the first ":catch" is found.
6010     // "finally" is set when ":finally" or ":endtry" is found
6011     try_scope->se_u.se_try.ts_try_label = instr->ga_len;
6012     if (generate_instr(cctx, ISN_TRY) == NULL)
6013 	return NULL;
6014 
6015     // scope for the try block itself
6016     scope = new_scope(cctx, BLOCK_SCOPE);
6017     if (scope == NULL)
6018 	return NULL;
6019 
6020     return arg;
6021 }
6022 
6023 /*
6024  * compile "catch {expr}"
6025  */
6026     static char_u *
6027 compile_catch(char_u *arg, cctx_T *cctx UNUSED)
6028 {
6029     scope_T	*scope = cctx->ctx_scope;
6030     garray_T	*instr = &cctx->ctx_instr;
6031     char_u	*p;
6032     isn_T	*isn;
6033 
6034     // end block scope from :try or :catch
6035     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
6036 	compile_endblock(cctx);
6037     scope = cctx->ctx_scope;
6038 
6039     // Error if not in a :try scope
6040     if (scope == NULL || scope->se_type != TRY_SCOPE)
6041     {
6042 	emsg(_(e_catch));
6043 	return NULL;
6044     }
6045 
6046     if (scope->se_u.se_try.ts_caught_all)
6047     {
6048 	emsg(_(e_catch_unreachable_after_catch_all));
6049 	return NULL;
6050     }
6051 
6052     // Jump from end of previous block to :finally or :endtry
6053     if (compile_jump_to_end(&scope->se_u.se_try.ts_end_label,
6054 						    JUMP_ALWAYS, cctx) == FAIL)
6055 	return NULL;
6056 
6057     // End :try or :catch scope: set value in ISN_TRY instruction
6058     isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
6059     if (isn->isn_arg.try.try_catch == 0)
6060 	isn->isn_arg.try.try_catch = instr->ga_len;
6061     if (scope->se_u.se_try.ts_catch_label != 0)
6062     {
6063 	// Previous catch without match jumps here
6064 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_catch_label;
6065 	isn->isn_arg.jump.jump_where = instr->ga_len;
6066     }
6067 
6068     p = skipwhite(arg);
6069     if (ends_excmd2(arg, p))
6070     {
6071 	scope->se_u.se_try.ts_caught_all = TRUE;
6072 	scope->se_u.se_try.ts_catch_label = 0;
6073     }
6074     else
6075     {
6076 	char_u *end;
6077 	char_u *pat;
6078 	char_u *tofree = NULL;
6079 	int	dropped = 0;
6080 	int	len;
6081 
6082 	// Push v:exception, push {expr} and MATCH
6083 	generate_instr_type(cctx, ISN_PUSHEXC, &t_string);
6084 
6085 	end = skip_regexp_ex(p + 1, *p, TRUE, &tofree, &dropped);
6086 	if (*end != *p)
6087 	{
6088 	    semsg(_(e_separator_mismatch_str), p);
6089 	    vim_free(tofree);
6090 	    return FAIL;
6091 	}
6092 	if (tofree == NULL)
6093 	    len = (int)(end - (p + 1));
6094 	else
6095 	    len = (int)(end - tofree);
6096 	pat = vim_strnsave(tofree == NULL ? p + 1 : tofree, len);
6097 	vim_free(tofree);
6098 	p += len + 2 + dropped;
6099 	if (pat == NULL)
6100 	    return FAIL;
6101 	if (generate_PUSHS(cctx, pat) == FAIL)
6102 	    return FAIL;
6103 
6104 	if (generate_COMPARE(cctx, EXPR_MATCH, FALSE) == FAIL)
6105 	    return NULL;
6106 
6107 	scope->se_u.se_try.ts_catch_label = instr->ga_len;
6108 	if (generate_JUMP(cctx, JUMP_IF_FALSE, 0) == FAIL)
6109 	    return NULL;
6110     }
6111 
6112     if (generate_instr(cctx, ISN_CATCH) == NULL)
6113 	return NULL;
6114 
6115     if (new_scope(cctx, BLOCK_SCOPE) == NULL)
6116 	return NULL;
6117     return p;
6118 }
6119 
6120     static char_u *
6121 compile_finally(char_u *arg, cctx_T *cctx)
6122 {
6123     scope_T	*scope = cctx->ctx_scope;
6124     garray_T	*instr = &cctx->ctx_instr;
6125     isn_T	*isn;
6126 
6127     // end block scope from :try or :catch
6128     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
6129 	compile_endblock(cctx);
6130     scope = cctx->ctx_scope;
6131 
6132     // Error if not in a :try scope
6133     if (scope == NULL || scope->se_type != TRY_SCOPE)
6134     {
6135 	emsg(_(e_finally));
6136 	return NULL;
6137     }
6138 
6139     // End :catch or :finally scope: set value in ISN_TRY instruction
6140     isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
6141     if (isn->isn_arg.try.try_finally != 0)
6142     {
6143 	emsg(_(e_finally_dup));
6144 	return NULL;
6145     }
6146 
6147     // Fill in the "end" label in jumps at the end of the blocks.
6148     compile_fill_jump_to_end(&scope->se_u.se_try.ts_end_label, cctx);
6149 
6150     isn->isn_arg.try.try_finally = instr->ga_len;
6151     if (scope->se_u.se_try.ts_catch_label != 0)
6152     {
6153 	// Previous catch without match jumps here
6154 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_catch_label;
6155 	isn->isn_arg.jump.jump_where = instr->ga_len;
6156 	scope->se_u.se_try.ts_catch_label = 0;
6157     }
6158 
6159     // TODO: set index in ts_finally_label jumps
6160 
6161     return arg;
6162 }
6163 
6164     static char_u *
6165 compile_endtry(char_u *arg, cctx_T *cctx)
6166 {
6167     scope_T	*scope = cctx->ctx_scope;
6168     garray_T	*instr = &cctx->ctx_instr;
6169     isn_T	*isn;
6170 
6171     // end block scope from :catch or :finally
6172     if (scope != NULL && scope->se_type == BLOCK_SCOPE)
6173 	compile_endblock(cctx);
6174     scope = cctx->ctx_scope;
6175 
6176     // Error if not in a :try scope
6177     if (scope == NULL || scope->se_type != TRY_SCOPE)
6178     {
6179 	if (scope == NULL)
6180 	    emsg(_(e_no_endtry));
6181 	else if (scope->se_type == WHILE_SCOPE)
6182 	    emsg(_(e_endwhile));
6183 	else if (scope->se_type == FOR_SCOPE)
6184 	    emsg(_(e_endfor));
6185 	else
6186 	    emsg(_(e_endif));
6187 	return NULL;
6188     }
6189 
6190     isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_try_label;
6191     if (isn->isn_arg.try.try_catch == 0 && isn->isn_arg.try.try_finally == 0)
6192     {
6193 	emsg(_(e_missing_catch_or_finally));
6194 	return NULL;
6195     }
6196 
6197     // Fill in the "end" label in jumps at the end of the blocks, if not done
6198     // by ":finally".
6199     compile_fill_jump_to_end(&scope->se_u.se_try.ts_end_label, cctx);
6200 
6201     // End :catch or :finally scope: set value in ISN_TRY instruction
6202     if (isn->isn_arg.try.try_catch == 0)
6203 	isn->isn_arg.try.try_catch = instr->ga_len;
6204     if (isn->isn_arg.try.try_finally == 0)
6205 	isn->isn_arg.try.try_finally = instr->ga_len;
6206 
6207     if (scope->se_u.se_try.ts_catch_label != 0)
6208     {
6209 	// Last catch without match jumps here
6210 	isn = ((isn_T *)instr->ga_data) + scope->se_u.se_try.ts_catch_label;
6211 	isn->isn_arg.jump.jump_where = instr->ga_len;
6212     }
6213 
6214     compile_endblock(cctx);
6215 
6216     if (generate_instr(cctx, ISN_ENDTRY) == NULL)
6217 	return NULL;
6218     return arg;
6219 }
6220 
6221 /*
6222  * compile "throw {expr}"
6223  */
6224     static char_u *
6225 compile_throw(char_u *arg, cctx_T *cctx UNUSED)
6226 {
6227     char_u *p = skipwhite(arg);
6228 
6229     if (compile_expr0(&p, cctx) == FAIL)
6230 	return NULL;
6231     if (may_generate_2STRING(-1, cctx) == FAIL)
6232 	return NULL;
6233     if (generate_instr_drop(cctx, ISN_THROW, 1) == NULL)
6234 	return NULL;
6235 
6236     return p;
6237 }
6238 
6239 /*
6240  * compile "echo expr"
6241  * compile "echomsg expr"
6242  * compile "echoerr expr"
6243  * compile "execute expr"
6244  */
6245     static char_u *
6246 compile_mult_expr(char_u *arg, int cmdidx, cctx_T *cctx)
6247 {
6248     char_u	*p = arg;
6249     char_u	*prev;
6250     int		count = 0;
6251 
6252     for (;;)
6253     {
6254 	if (compile_expr0(&p, cctx) == FAIL)
6255 	    return NULL;
6256 	++count;
6257 	prev = p;
6258 	p = skipwhite(p);
6259 	if (ends_excmd2(prev, p))
6260 	    break;
6261     }
6262 
6263     if (cmdidx == CMD_echo || cmdidx == CMD_echon)
6264 	generate_ECHO(cctx, cmdidx == CMD_echo, count);
6265     else if (cmdidx == CMD_execute)
6266 	generate_MULT_EXPR(cctx, ISN_EXECUTE, count);
6267     else if (cmdidx == CMD_echomsg)
6268 	generate_MULT_EXPR(cctx, ISN_ECHOMSG, count);
6269     else
6270 	generate_MULT_EXPR(cctx, ISN_ECHOERR, count);
6271     return p;
6272 }
6273 
6274 /*
6275  * A command that is not compiled, execute with legacy code.
6276  */
6277     static char_u *
6278 compile_exec(char_u *line, exarg_T *eap, cctx_T *cctx)
6279 {
6280     char_u  *p;
6281     int	    has_expr = FALSE;
6282     char_u  *nextcmd = (char_u *)"";
6283 
6284     if (cctx->ctx_skip == SKIP_YES)
6285 	goto theend;
6286 
6287     if (eap->cmdidx >= 0 && eap->cmdidx < CMD_SIZE)
6288     {
6289 	long	argt = excmd_get_argt(eap->cmdidx);
6290 	int	usefilter = FALSE;
6291 
6292 	has_expr = argt & (EX_XFILE | EX_EXPAND);
6293 
6294 	// If the command can be followed by a bar, find the bar and truncate
6295 	// it, so that the following command can be compiled.
6296 	// The '|' is overwritten with a NUL, it is put back below.
6297 	if ((eap->cmdidx == CMD_write || eap->cmdidx == CMD_read)
6298 							   && *eap->arg == '!')
6299 	    // :w !filter or :r !filter or :r! filter
6300 	    usefilter = TRUE;
6301 	if ((argt & EX_TRLBAR) && !usefilter)
6302 	{
6303 	    eap->argt = argt;
6304 	    separate_nextcmd(eap);
6305 	    if (eap->nextcmd != NULL)
6306 		nextcmd = eap->nextcmd;
6307 	}
6308     }
6309 
6310     if (eap->cmdidx == CMD_syntax && STRNCMP(eap->arg, "include ", 8) == 0)
6311     {
6312 	// expand filename in "syntax include [@group] filename"
6313 	has_expr = TRUE;
6314 	eap->arg = skipwhite(eap->arg + 7);
6315 	if (*eap->arg == '@')
6316 	    eap->arg = skiptowhite(eap->arg);
6317     }
6318 
6319     if (has_expr && (p = (char_u *)strstr((char *)eap->arg, "`=")) != NULL)
6320     {
6321 	int	count = 0;
6322 	char_u	*start = skipwhite(line);
6323 
6324 	// :cmd xxx`=expr1`yyy`=expr2`zzz
6325 	// PUSHS ":cmd xxx"
6326 	// eval expr1
6327 	// PUSHS "yyy"
6328 	// eval expr2
6329 	// PUSHS "zzz"
6330 	// EXECCONCAT 5
6331 	for (;;)
6332 	{
6333 	    if (p > start)
6334 	    {
6335 		generate_PUSHS(cctx, vim_strnsave(start, p - start));
6336 		++count;
6337 	    }
6338 	    p += 2;
6339 	    if (compile_expr0(&p, cctx) == FAIL)
6340 		return NULL;
6341 	    may_generate_2STRING(-1, cctx);
6342 	    ++count;
6343 	    p = skipwhite(p);
6344 	    if (*p != '`')
6345 	    {
6346 		emsg(_(e_missing_backtick));
6347 		return NULL;
6348 	    }
6349 	    start = p + 1;
6350 
6351 	    p = (char_u *)strstr((char *)start, "`=");
6352 	    if (p == NULL)
6353 	    {
6354 		if (*skipwhite(start) != NUL)
6355 		{
6356 		    generate_PUSHS(cctx, vim_strsave(start));
6357 		    ++count;
6358 		}
6359 		break;
6360 	    }
6361 	}
6362 	generate_EXECCONCAT(cctx, count);
6363     }
6364     else
6365 	generate_EXEC(cctx, line);
6366 
6367 theend:
6368     if (*nextcmd != NUL)
6369     {
6370 	// the parser expects a pointer to the bar, put it back
6371 	--nextcmd;
6372 	*nextcmd = '|';
6373     }
6374 
6375     return nextcmd;
6376 }
6377 
6378 /*
6379  * Add a function to the list of :def functions.
6380  * This sets "ufunc->uf_dfunc_idx" but the function isn't compiled yet.
6381  */
6382     static int
6383 add_def_function(ufunc_T *ufunc)
6384 {
6385     dfunc_T *dfunc;
6386 
6387     if (def_functions.ga_len == 0)
6388     {
6389 	// The first position is not used, so that a zero uf_dfunc_idx means it
6390 	// wasn't set.
6391 	if (ga_grow(&def_functions, 1) == FAIL)
6392 	    return FAIL;
6393 	++def_functions.ga_len;
6394     }
6395 
6396     // Add the function to "def_functions".
6397     if (ga_grow(&def_functions, 1) == FAIL)
6398 	return FAIL;
6399     dfunc = ((dfunc_T *)def_functions.ga_data) + def_functions.ga_len;
6400     CLEAR_POINTER(dfunc);
6401     dfunc->df_idx = def_functions.ga_len;
6402     ufunc->uf_dfunc_idx = dfunc->df_idx;
6403     dfunc->df_ufunc = ufunc;
6404     ++def_functions.ga_len;
6405     return OK;
6406 }
6407 
6408 /*
6409  * After ex_function() has collected all the function lines: parse and compile
6410  * the lines into instructions.
6411  * Adds the function to "def_functions".
6412  * When "set_return_type" is set then set ufunc->uf_ret_type to the type of the
6413  * return statement (used for lambda).
6414  * "outer_cctx" is set for a nested function.
6415  * This can be used recursively through compile_lambda(), which may reallocate
6416  * "def_functions".
6417  * Returns OK or FAIL.
6418  */
6419     int
6420 compile_def_function(ufunc_T *ufunc, int set_return_type, cctx_T *outer_cctx)
6421 {
6422     char_u	*line = NULL;
6423     char_u	*p;
6424     char	*errormsg = NULL;	// error message
6425     cctx_T	cctx;
6426     garray_T	*instr;
6427     int		called_emsg_before = called_emsg;
6428     int		ret = FAIL;
6429     sctx_T	save_current_sctx = current_sctx;
6430     int		do_estack_push;
6431     int		emsg_before = called_emsg;
6432     int		new_def_function = FALSE;
6433 
6434     // When using a function that was compiled before: Free old instructions.
6435     // Otherwise add a new entry in "def_functions".
6436     if (ufunc->uf_dfunc_idx > 0)
6437     {
6438 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
6439 							 + ufunc->uf_dfunc_idx;
6440 	delete_def_function_contents(dfunc);
6441     }
6442     else
6443     {
6444 	if (add_def_function(ufunc) == FAIL)
6445 	    return FAIL;
6446 	new_def_function = TRUE;
6447     }
6448 
6449     ufunc->uf_def_status = UF_COMPILING;
6450 
6451     CLEAR_FIELD(cctx);
6452     cctx.ctx_ufunc = ufunc;
6453     cctx.ctx_lnum = -1;
6454     cctx.ctx_outer = outer_cctx;
6455     ga_init2(&cctx.ctx_locals, sizeof(lvar_T), 10);
6456     ga_init2(&cctx.ctx_type_stack, sizeof(type_T *), 50);
6457     ga_init2(&cctx.ctx_imports, sizeof(imported_T), 10);
6458     cctx.ctx_type_list = &ufunc->uf_type_list;
6459     ga_init2(&cctx.ctx_instr, sizeof(isn_T), 50);
6460     instr = &cctx.ctx_instr;
6461 
6462     // Set the context to the function, it may be compiled when called from
6463     // another script.  Set the script version to the most modern one.
6464     // The line number will be set in next_line_from_context().
6465     current_sctx = ufunc->uf_script_ctx;
6466     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
6467 
6468     // Make sure error messages are OK.
6469     do_estack_push = !estack_top_is_ufunc(ufunc, 1);
6470     if (do_estack_push)
6471 	estack_push_ufunc(ufunc, 1);
6472 
6473     if (ufunc->uf_def_args.ga_len > 0)
6474     {
6475 	int	count = ufunc->uf_def_args.ga_len;
6476 	int	first_def_arg = ufunc->uf_args.ga_len - count;
6477 	int	i;
6478 	char_u	*arg;
6479 	int	off = STACK_FRAME_SIZE + (ufunc->uf_va_name != NULL ? 1 : 0);
6480 	int	did_set_arg_type = FALSE;
6481 
6482 	// Produce instructions for the default values of optional arguments.
6483 	// Store the instruction index in uf_def_arg_idx[] so that we know
6484 	// where to start when the function is called, depending on the number
6485 	// of arguments.
6486 	ufunc->uf_def_arg_idx = ALLOC_CLEAR_MULT(int, count + 1);
6487 	if (ufunc->uf_def_arg_idx == NULL)
6488 	    goto erret;
6489 	for (i = 0; i < count; ++i)
6490 	{
6491 	    garray_T	*stack = &cctx.ctx_type_stack;
6492 	    type_T	*val_type;
6493 	    int		arg_idx = first_def_arg + i;
6494 
6495 	    ufunc->uf_def_arg_idx[i] = instr->ga_len;
6496 	    arg = ((char_u **)(ufunc->uf_def_args.ga_data))[i];
6497 	    if (compile_expr0(&arg, &cctx) == FAIL)
6498 		goto erret;
6499 
6500 	    // If no type specified use the type of the default value.
6501 	    // Otherwise check that the default value type matches the
6502 	    // specified type.
6503 	    val_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
6504 	    if (ufunc->uf_arg_types[arg_idx] == &t_unknown)
6505 	    {
6506 		did_set_arg_type = TRUE;
6507 		ufunc->uf_arg_types[arg_idx] = val_type;
6508 	    }
6509 	    else if (check_type(ufunc->uf_arg_types[arg_idx], val_type,
6510 						    TRUE, arg_idx + 1) == FAIL)
6511 		goto erret;
6512 
6513 	    if (generate_STORE(&cctx, ISN_STORE, i - count - off, NULL) == FAIL)
6514 		goto erret;
6515 	}
6516 	ufunc->uf_def_arg_idx[count] = instr->ga_len;
6517 
6518 	if (did_set_arg_type)
6519 	    set_function_type(ufunc);
6520     }
6521 
6522     /*
6523      * Loop over all the lines of the function and generate instructions.
6524      */
6525     for (;;)
6526     {
6527 	exarg_T	    ea;
6528 	cmdmod_T    save_cmdmod;
6529 	int	    starts_with_colon = FALSE;
6530 	char_u	    *cmd;
6531 	int	    save_msg_scroll = msg_scroll;
6532 
6533 	// Bail out on the first error to avoid a flood of errors and report
6534 	// the right line number when inside try/catch.
6535 	if (emsg_before != called_emsg)
6536 	    goto erret;
6537 
6538 	if (line != NULL && *line == '|')
6539 	    // the line continues after a '|'
6540 	    ++line;
6541 	else if (line != NULL && *skipwhite(line) != NUL
6542 		&& !(*line == '#' && (line == cctx.ctx_line_start
6543 						    || VIM_ISWHITE(line[-1]))))
6544 	{
6545 	    semsg(_(e_trailing_arg), line);
6546 	    goto erret;
6547 	}
6548 	else
6549 	{
6550 	    line = next_line_from_context(&cctx, FALSE);
6551 	    if (cctx.ctx_lnum >= ufunc->uf_lines.ga_len)
6552 		// beyond the last line
6553 		break;
6554 	}
6555 	emsg_before = called_emsg;
6556 
6557 	CLEAR_FIELD(ea);
6558 	ea.cmdlinep = &line;
6559 	ea.cmd = skipwhite(line);
6560 
6561 	// Some things can be recognized by the first character.
6562 	switch (*ea.cmd)
6563 	{
6564 	    case '#':
6565 		// "#" starts a comment, but "#{" does not.
6566 		if (ea.cmd[1] != '{')
6567 		{
6568 		    line = (char_u *)"";
6569 		    continue;
6570 		}
6571 		break;
6572 
6573 	    case '}':
6574 		{
6575 		    // "}" ends a block scope
6576 		    scopetype_T stype = cctx.ctx_scope == NULL
6577 					  ? NO_SCOPE : cctx.ctx_scope->se_type;
6578 
6579 		    if (stype == BLOCK_SCOPE)
6580 		    {
6581 			compile_endblock(&cctx);
6582 			line = ea.cmd;
6583 		    }
6584 		    else
6585 		    {
6586 			emsg(_(e_using_rcurly_outside_if_block_scope));
6587 			goto erret;
6588 		    }
6589 		    if (line != NULL)
6590 			line = skipwhite(ea.cmd + 1);
6591 		    continue;
6592 		}
6593 
6594 	    case '{':
6595 		// "{" starts a block scope
6596 		// "{'a': 1}->func() is something else
6597 		if (ends_excmd(*skipwhite(ea.cmd + 1)))
6598 		{
6599 		    line = compile_block(ea.cmd, &cctx);
6600 		    continue;
6601 		}
6602 		break;
6603 
6604 	    case ':':
6605 		starts_with_colon = TRUE;
6606 		break;
6607 	}
6608 
6609 	/*
6610 	 * COMMAND MODIFIERS
6611 	 */
6612 	save_cmdmod = cmdmod;
6613 	if (parse_command_modifiers(&ea, &errormsg, FALSE) == FAIL)
6614 	{
6615 	    if (errormsg != NULL)
6616 		goto erret;
6617 	    // empty line or comment
6618 	    line = (char_u *)"";
6619 	    continue;
6620 	}
6621 	// TODO: use modifiers in the command
6622 	undo_cmdmod(&ea, save_msg_scroll);
6623 	cmdmod = save_cmdmod;
6624 
6625 	// Skip ":call" to get to the function name.
6626 	p = ea.cmd;
6627 	if (checkforcmd(&ea.cmd, "call", 3))
6628 	{
6629 	    if (*ea.cmd == '(')
6630 		// not for "call()"
6631 		ea.cmd = p;
6632 	    else
6633 		ea.cmd = skipwhite(ea.cmd);
6634 	}
6635 
6636 	if (!starts_with_colon)
6637 	{
6638 	    char_u *pskip;
6639 
6640 	    // Assuming the command starts with a variable or function name,
6641 	    // find what follows.
6642 	    // Skip over "var.member", "var[idx]" and the like.
6643 	    // Also "&opt = val", "$ENV = val" and "@r = val".
6644 	    pskip = (*ea.cmd == '&' || *ea.cmd == '$' || *ea.cmd == '@')
6645 							 ? ea.cmd + 1 : ea.cmd;
6646 	    p = to_name_end(pskip, TRUE);
6647 	    if (p > ea.cmd && *p != NUL)
6648 	    {
6649 		char_u *var_end;
6650 		int	oplen;
6651 		int	heredoc;
6652 
6653 		if (ea.cmd[0] == '@')
6654 		    var_end = ea.cmd + 2;
6655 		else
6656 		    var_end = find_name_end(pskip, NULL, NULL,
6657 						FNE_CHECK_START | FNE_INCL_BR);
6658 		oplen = assignment_len(skipwhite(var_end), &heredoc);
6659 		if (oplen > 0)
6660 		{
6661 		    size_t len = p - ea.cmd;
6662 
6663 		    // Recognize an assignment if we recognize the variable
6664 		    // name:
6665 		    // "g:var = expr"
6666 		    // "local = expr"  where "local" is a local var.
6667 		    // "script = expr"  where "script" is a script-local var.
6668 		    // "import = expr"  where "import" is an imported var
6669 		    // "&opt = expr"
6670 		    // "$ENV = expr"
6671 		    // "@r = expr"
6672 		    if (*ea.cmd == '&'
6673 			    || *ea.cmd == '$'
6674 			    || *ea.cmd == '@'
6675 			    || ((len) > 2 && ea.cmd[1] == ':')
6676 			    || lookup_local(ea.cmd, len, &cctx) != NULL
6677 			    || lookup_arg(ea.cmd, len, NULL, NULL,
6678 							     NULL, &cctx) == OK
6679 			    || lookup_script(ea.cmd, len, FALSE) == OK
6680 			    || find_imported(ea.cmd, len, &cctx) != NULL)
6681 		    {
6682 			line = compile_assignment(ea.cmd, &ea, CMD_SIZE, &cctx);
6683 			if (line == NULL || line == ea.cmd)
6684 			    goto erret;
6685 			continue;
6686 		    }
6687 		}
6688 	    }
6689 
6690 	    if (*ea.cmd == '[')
6691 	    {
6692 		// [var, var] = expr
6693 		line = compile_assignment(ea.cmd, &ea, CMD_SIZE, &cctx);
6694 		if (line == NULL)
6695 		    goto erret;
6696 		if (line != ea.cmd)
6697 		    continue;
6698 	    }
6699 	}
6700 
6701 	/*
6702 	 * COMMAND after range
6703 	 * 'text'->func() should not be confused with 'a mark
6704 	 */
6705 	cmd = ea.cmd;
6706 	if (*cmd != '\'' || starts_with_colon)
6707 	{
6708 	    ea.cmd = skip_range(ea.cmd, NULL);
6709 	    if (ea.cmd > cmd)
6710 	    {
6711 		if (!starts_with_colon)
6712 		{
6713 		    emsg(_(e_colon_required_before_a_range));
6714 		    goto erret;
6715 		}
6716 		if (ends_excmd2(line, ea.cmd))
6717 		{
6718 		    // A range without a command: jump to the line.
6719 		    // TODO: compile to a more efficient command, possibly
6720 		    // calling parse_cmd_address().
6721 		    ea.cmdidx = CMD_SIZE;
6722 		    line = compile_exec(line, &ea, &cctx);
6723 		    goto nextline;
6724 		}
6725 	    }
6726 	}
6727 	p = find_ex_command(&ea, NULL, starts_with_colon ? NULL
6728 		   : (void *(*)(char_u *, size_t, cctx_T *))lookup_local,
6729 									&cctx);
6730 
6731 	if (p == ea.cmd && ea.cmdidx != CMD_SIZE)
6732 	{
6733 	    if (cctx.ctx_skip == SKIP_YES)
6734 	    {
6735 		line += STRLEN(line);
6736 		continue;
6737 	    }
6738 
6739 	    // Expression or function call.
6740 	    if (ea.cmdidx != CMD_eval)
6741 	    {
6742 		// CMD_let cannot happen, compile_assignment() above is used
6743 		iemsg("Command from find_ex_command() not handled");
6744 		goto erret;
6745 	    }
6746 	}
6747 
6748 	p = skipwhite(p);
6749 
6750 	if (cctx.ctx_had_return
6751 		&& ea.cmdidx != CMD_elseif
6752 		&& ea.cmdidx != CMD_else
6753 		&& ea.cmdidx != CMD_endif
6754 		&& ea.cmdidx != CMD_endfor
6755 		&& ea.cmdidx != CMD_endwhile
6756 		&& ea.cmdidx != CMD_catch
6757 		&& ea.cmdidx != CMD_finally
6758 		&& ea.cmdidx != CMD_endtry)
6759 	{
6760 	    emsg(_(e_unreachable_code_after_return));
6761 	    goto erret;
6762 	}
6763 
6764 	switch (ea.cmdidx)
6765 	{
6766 	    case CMD_def:
6767 		    ea.arg = p;
6768 		    line = compile_nested_function(&ea, &cctx);
6769 		    break;
6770 
6771 	    case CMD_function:
6772 		    // TODO: should we allow this, e.g. to declare a global
6773 		    // function?
6774 		    emsg(_(e_cannot_use_function_inside_def));
6775 		    goto erret;
6776 
6777 	    case CMD_return:
6778 		    line = compile_return(p, set_return_type, &cctx);
6779 		    cctx.ctx_had_return = TRUE;
6780 		    break;
6781 
6782 	    case CMD_let:
6783 	    case CMD_const:
6784 		    line = compile_assignment(p, &ea, ea.cmdidx, &cctx);
6785 		    if (line == p)
6786 			line = NULL;
6787 		    break;
6788 
6789 	    case CMD_unlet:
6790 	    case CMD_unlockvar:
6791 	    case CMD_lockvar:
6792 		    line = compile_unletlock(p, &ea, &cctx);
6793 		    break;
6794 
6795 	    case CMD_import:
6796 		    line = compile_import(p, &cctx);
6797 		    break;
6798 
6799 	    case CMD_if:
6800 		    line = compile_if(p, &cctx);
6801 		    break;
6802 	    case CMD_elseif:
6803 		    line = compile_elseif(p, &cctx);
6804 		    cctx.ctx_had_return = FALSE;
6805 		    break;
6806 	    case CMD_else:
6807 		    line = compile_else(p, &cctx);
6808 		    cctx.ctx_had_return = FALSE;
6809 		    break;
6810 	    case CMD_endif:
6811 		    line = compile_endif(p, &cctx);
6812 		    break;
6813 
6814 	    case CMD_while:
6815 		    line = compile_while(p, &cctx);
6816 		    break;
6817 	    case CMD_endwhile:
6818 		    line = compile_endwhile(p, &cctx);
6819 		    cctx.ctx_had_return = FALSE;
6820 		    break;
6821 
6822 	    case CMD_for:
6823 		    line = compile_for(p, &cctx);
6824 		    break;
6825 	    case CMD_endfor:
6826 		    line = compile_endfor(p, &cctx);
6827 		    cctx.ctx_had_return = FALSE;
6828 		    break;
6829 	    case CMD_continue:
6830 		    line = compile_continue(p, &cctx);
6831 		    break;
6832 	    case CMD_break:
6833 		    line = compile_break(p, &cctx);
6834 		    break;
6835 
6836 	    case CMD_try:
6837 		    line = compile_try(p, &cctx);
6838 		    break;
6839 	    case CMD_catch:
6840 		    line = compile_catch(p, &cctx);
6841 		    cctx.ctx_had_return = FALSE;
6842 		    break;
6843 	    case CMD_finally:
6844 		    line = compile_finally(p, &cctx);
6845 		    cctx.ctx_had_return = FALSE;
6846 		    break;
6847 	    case CMD_endtry:
6848 		    line = compile_endtry(p, &cctx);
6849 		    cctx.ctx_had_return = FALSE;
6850 		    break;
6851 	    case CMD_throw:
6852 		    line = compile_throw(p, &cctx);
6853 		    break;
6854 
6855 	    case CMD_eval:
6856 		    if (compile_expr0(&p, &cctx) == FAIL)
6857 			goto erret;
6858 
6859 		    // drop the result
6860 		    generate_instr_drop(&cctx, ISN_DROP, 1);
6861 
6862 		    line = skipwhite(p);
6863 		    break;
6864 
6865 	    case CMD_echo:
6866 	    case CMD_echon:
6867 	    case CMD_execute:
6868 	    case CMD_echomsg:
6869 	    case CMD_echoerr:
6870 		    line = compile_mult_expr(p, ea.cmdidx, &cctx);
6871 		    break;
6872 
6873 	    // TODO: any other commands with an expression argument?
6874 
6875 	    case CMD_append:
6876 	    case CMD_change:
6877 	    case CMD_insert:
6878 	    case CMD_t:
6879 	    case CMD_xit:
6880 		    not_in_vim9(&ea);
6881 		    goto erret;
6882 
6883 	    case CMD_SIZE:
6884 		    if (cctx.ctx_skip != SKIP_YES)
6885 		    {
6886 			semsg(_(e_invalid_command_str), ea.cmd);
6887 			goto erret;
6888 		    }
6889 		    // We don't check for a next command here.
6890 		    line = (char_u *)"";
6891 		    break;
6892 
6893 	    default:
6894 		    if (cctx.ctx_skip == SKIP_YES)
6895 		    {
6896 			// We don't check for a next command here.
6897 			line = (char_u *)"";
6898 		    }
6899 		    else
6900 		    {
6901 			// Not recognized, execute with do_cmdline_cmd().
6902 			ea.arg = p;
6903 			line = compile_exec(line, &ea, &cctx);
6904 		    }
6905 		    break;
6906 	}
6907 nextline:
6908 	if (line == NULL)
6909 	    goto erret;
6910 	line = skipwhite(line);
6911 
6912 	if (cctx.ctx_type_stack.ga_len < 0)
6913 	{
6914 	    iemsg("Type stack underflow");
6915 	    goto erret;
6916 	}
6917     }
6918 
6919     if (cctx.ctx_scope != NULL)
6920     {
6921 	if (cctx.ctx_scope->se_type == IF_SCOPE)
6922 	    emsg(_(e_endif));
6923 	else if (cctx.ctx_scope->se_type == WHILE_SCOPE)
6924 	    emsg(_(e_endwhile));
6925 	else if (cctx.ctx_scope->se_type == FOR_SCOPE)
6926 	    emsg(_(e_endfor));
6927 	else
6928 	    emsg(_(e_missing_rcurly));
6929 	goto erret;
6930     }
6931 
6932     if (!cctx.ctx_had_return)
6933     {
6934 	if (ufunc->uf_ret_type->tt_type != VAR_VOID)
6935 	{
6936 	    emsg(_(e_missing_return_statement));
6937 	    goto erret;
6938 	}
6939 
6940 	// Return zero if there is no return at the end.
6941 	generate_PUSHNR(&cctx, 0);
6942 	generate_instr(&cctx, ISN_RETURN);
6943     }
6944 
6945     {
6946 	dfunc_T	*dfunc = ((dfunc_T *)def_functions.ga_data)
6947 							 + ufunc->uf_dfunc_idx;
6948 	dfunc->df_deleted = FALSE;
6949 	dfunc->df_instr = instr->ga_data;
6950 	dfunc->df_instr_count = instr->ga_len;
6951 	dfunc->df_varcount = cctx.ctx_locals_count;
6952 	dfunc->df_closure_count = cctx.ctx_closure_count;
6953 	if (cctx.ctx_outer_used)
6954 	    ufunc->uf_flags |= FC_CLOSURE;
6955 	ufunc->uf_def_status = UF_COMPILED;
6956     }
6957 
6958     ret = OK;
6959 
6960 erret:
6961     if (ret == FAIL)
6962     {
6963 	int idx;
6964 	dfunc_T	*dfunc = ((dfunc_T *)def_functions.ga_data)
6965 							 + ufunc->uf_dfunc_idx;
6966 
6967 	for (idx = 0; idx < instr->ga_len; ++idx)
6968 	    delete_instr(((isn_T *)instr->ga_data) + idx);
6969 	ga_clear(instr);
6970 
6971 	// If using the last entry in the table and it was added above, we
6972 	// might as well remove it.
6973 	if (!dfunc->df_deleted && new_def_function
6974 			    && ufunc->uf_dfunc_idx == def_functions.ga_len - 1)
6975 	{
6976 	    --def_functions.ga_len;
6977 	    ufunc->uf_dfunc_idx = 0;
6978 	}
6979 	ufunc->uf_def_status = UF_NOT_COMPILED;
6980 
6981 	while (cctx.ctx_scope != NULL)
6982 	    drop_scope(&cctx);
6983 
6984 	// Don't execute this function body.
6985 	ga_clear_strings(&ufunc->uf_lines);
6986 
6987 	if (errormsg != NULL)
6988 	    emsg(errormsg);
6989 	else if (called_emsg == called_emsg_before)
6990 	    emsg(_(e_compile_def_function_failed));
6991     }
6992 
6993     current_sctx = save_current_sctx;
6994     if (do_estack_push)
6995 	estack_pop();
6996 
6997     free_imported(&cctx);
6998     free_locals(&cctx);
6999     ga_clear(&cctx.ctx_type_stack);
7000     return ret;
7001 }
7002 
7003     void
7004 set_function_type(ufunc_T *ufunc)
7005 {
7006     int varargs = ufunc->uf_va_name != NULL;
7007     int argcount = ufunc->uf_args.ga_len;
7008 
7009     // Create a type for the function, with the return type and any
7010     // argument types.
7011     // A vararg is included in uf_args.ga_len but not in uf_arg_types.
7012     // The type is included in "tt_args".
7013     if (argcount > 0 || varargs)
7014     {
7015 	ufunc->uf_func_type = alloc_func_type(ufunc->uf_ret_type,
7016 					   argcount, &ufunc->uf_type_list);
7017 	// Add argument types to the function type.
7018 	if (func_type_add_arg_types(ufunc->uf_func_type,
7019 				    argcount + varargs,
7020 				    &ufunc->uf_type_list) == FAIL)
7021 	    return;
7022 	ufunc->uf_func_type->tt_argcount = argcount + varargs;
7023 	ufunc->uf_func_type->tt_min_argcount =
7024 				      argcount - ufunc->uf_def_args.ga_len;
7025 	if (ufunc->uf_arg_types == NULL)
7026 	{
7027 	    int i;
7028 
7029 	    // lambda does not have argument types.
7030 	    for (i = 0; i < argcount; ++i)
7031 		ufunc->uf_func_type->tt_args[i] = &t_any;
7032 	}
7033 	else
7034 	    mch_memmove(ufunc->uf_func_type->tt_args,
7035 			 ufunc->uf_arg_types, sizeof(type_T *) * argcount);
7036 	if (varargs)
7037 	{
7038 	    ufunc->uf_func_type->tt_args[argcount] =
7039 		    ufunc->uf_va_type == NULL ? &t_any : ufunc->uf_va_type;
7040 	    ufunc->uf_func_type->tt_flags = TTFLAG_VARARGS;
7041 	}
7042     }
7043     else
7044 	// No arguments, can use a predefined type.
7045 	ufunc->uf_func_type = get_func_type(ufunc->uf_ret_type,
7046 					   argcount, &ufunc->uf_type_list);
7047 }
7048 
7049 
7050 /*
7051  * Delete an instruction, free what it contains.
7052  */
7053     void
7054 delete_instr(isn_T *isn)
7055 {
7056     switch (isn->isn_type)
7057     {
7058 	case ISN_EXEC:
7059 	case ISN_LOADENV:
7060 	case ISN_LOADG:
7061 	case ISN_LOADB:
7062 	case ISN_LOADW:
7063 	case ISN_LOADT:
7064 	case ISN_LOADOPT:
7065 	case ISN_STRINGMEMBER:
7066 	case ISN_PUSHEXC:
7067 	case ISN_PUSHS:
7068 	case ISN_STOREENV:
7069 	case ISN_STOREG:
7070 	case ISN_STOREB:
7071 	case ISN_STOREW:
7072 	case ISN_STORET:
7073 	case ISN_PUSHFUNC:
7074 	    vim_free(isn->isn_arg.string);
7075 	    break;
7076 
7077 	case ISN_LOADS:
7078 	case ISN_STORES:
7079 	    vim_free(isn->isn_arg.loadstore.ls_name);
7080 	    break;
7081 
7082 	case ISN_UNLET:
7083 	case ISN_UNLETENV:
7084 	    vim_free(isn->isn_arg.unlet.ul_name);
7085 	    break;
7086 
7087 	case ISN_STOREOPT:
7088 	    vim_free(isn->isn_arg.storeopt.so_name);
7089 	    break;
7090 
7091 	case ISN_PUSHBLOB:   // push blob isn_arg.blob
7092 	    blob_unref(isn->isn_arg.blob);
7093 	    break;
7094 
7095 	case ISN_PUSHJOB:
7096 #ifdef FEAT_JOB_CHANNEL
7097 	    job_unref(isn->isn_arg.job);
7098 #endif
7099 	    break;
7100 
7101 	case ISN_PUSHCHANNEL:
7102 #ifdef FEAT_JOB_CHANNEL
7103 	    channel_unref(isn->isn_arg.channel);
7104 #endif
7105 	    break;
7106 
7107 	case ISN_UCALL:
7108 	    vim_free(isn->isn_arg.ufunc.cuf_name);
7109 	    break;
7110 
7111 	case ISN_FUNCREF:
7112 	    {
7113 		dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
7114 					       + isn->isn_arg.funcref.fr_func;
7115 		func_ptr_unref(dfunc->df_ufunc);
7116 	    }
7117 	    break;
7118 
7119 	case ISN_NEWFUNC:
7120 	    {
7121 		char_u  *lambda = isn->isn_arg.newfunc.nf_lambda;
7122 		ufunc_T *ufunc = find_func_even_dead(lambda, TRUE, NULL);
7123 
7124 		if (ufunc != NULL)
7125 		{
7126 		    // Clear uf_dfunc_idx so that the function is deleted.
7127 		    clear_def_function(ufunc);
7128 		    ufunc->uf_dfunc_idx = 0;
7129 		    func_ptr_unref(ufunc);
7130 		}
7131 
7132 		vim_free(lambda);
7133 		vim_free(isn->isn_arg.newfunc.nf_global);
7134 	    }
7135 	    break;
7136 
7137 	case ISN_2BOOL:
7138 	case ISN_2STRING:
7139 	case ISN_2STRING_ANY:
7140 	case ISN_ADDBLOB:
7141 	case ISN_ADDLIST:
7142 	case ISN_ANYINDEX:
7143 	case ISN_ANYSLICE:
7144 	case ISN_BCALL:
7145 	case ISN_CATCH:
7146 	case ISN_CHECKLEN:
7147 	case ISN_CHECKNR:
7148 	case ISN_CHECKTYPE:
7149 	case ISN_COMPAREANY:
7150 	case ISN_COMPAREBLOB:
7151 	case ISN_COMPAREBOOL:
7152 	case ISN_COMPAREDICT:
7153 	case ISN_COMPAREFLOAT:
7154 	case ISN_COMPAREFUNC:
7155 	case ISN_COMPARELIST:
7156 	case ISN_COMPARENR:
7157 	case ISN_COMPARESPECIAL:
7158 	case ISN_COMPARESTRING:
7159 	case ISN_CONCAT:
7160 	case ISN_DCALL:
7161 	case ISN_DROP:
7162 	case ISN_ECHO:
7163 	case ISN_ECHOERR:
7164 	case ISN_ECHOMSG:
7165 	case ISN_ENDTRY:
7166 	case ISN_EXECCONCAT:
7167 	case ISN_EXECUTE:
7168 	case ISN_FOR:
7169 	case ISN_GETITEM:
7170 	case ISN_JUMP:
7171 	case ISN_LISTINDEX:
7172 	case ISN_LISTSLICE:
7173 	case ISN_LOAD:
7174 	case ISN_LOADBDICT:
7175 	case ISN_LOADGDICT:
7176 	case ISN_LOADOUTER:
7177 	case ISN_LOADREG:
7178 	case ISN_LOADSCRIPT:
7179 	case ISN_LOADTDICT:
7180 	case ISN_LOADV:
7181 	case ISN_LOADWDICT:
7182 	case ISN_MEMBER:
7183 	case ISN_NEGATENR:
7184 	case ISN_NEWDICT:
7185 	case ISN_NEWLIST:
7186 	case ISN_OPANY:
7187 	case ISN_OPFLOAT:
7188 	case ISN_OPNR:
7189 	case ISN_PCALL:
7190 	case ISN_PCALL_END:
7191 	case ISN_PUSHBOOL:
7192 	case ISN_PUSHF:
7193 	case ISN_PUSHNR:
7194 	case ISN_PUSHSPEC:
7195 	case ISN_RETURN:
7196 	case ISN_SHUFFLE:
7197 	case ISN_SLICE:
7198 	case ISN_STORE:
7199 	case ISN_STOREDICT:
7200 	case ISN_STORELIST:
7201 	case ISN_STORENR:
7202 	case ISN_STOREOUTER:
7203 	case ISN_STOREREG:
7204 	case ISN_STORESCRIPT:
7205 	case ISN_STOREV:
7206 	case ISN_STRINDEX:
7207 	case ISN_STRSLICE:
7208 	case ISN_THROW:
7209 	case ISN_TRY:
7210 	    // nothing allocated
7211 	    break;
7212     }
7213 }
7214 
7215 /*
7216  * Free all instructions for "dfunc".
7217  */
7218     static void
7219 delete_def_function_contents(dfunc_T *dfunc)
7220 {
7221     int idx;
7222 
7223     ga_clear(&dfunc->df_def_args_isn);
7224 
7225     if (dfunc->df_instr != NULL)
7226     {
7227 	for (idx = 0; idx < dfunc->df_instr_count; ++idx)
7228 	    delete_instr(dfunc->df_instr + idx);
7229 	VIM_CLEAR(dfunc->df_instr);
7230     }
7231 
7232     dfunc->df_deleted = TRUE;
7233 }
7234 
7235 /*
7236  * When a user function is deleted, clear the contents of any associated def
7237  * function.  The position in def_functions can be re-used.
7238  */
7239     void
7240 clear_def_function(ufunc_T *ufunc)
7241 {
7242     if (ufunc->uf_dfunc_idx > 0)
7243     {
7244 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data)
7245 							 + ufunc->uf_dfunc_idx;
7246 
7247 	delete_def_function_contents(dfunc);
7248 	ufunc->uf_def_status = UF_NOT_COMPILED;
7249     }
7250 }
7251 
7252 #if defined(EXITFREE) || defined(PROTO)
7253 /*
7254  * Free all functions defined with ":def".
7255  */
7256     void
7257 free_def_functions(void)
7258 {
7259     int idx;
7260 
7261     for (idx = 0; idx < def_functions.ga_len; ++idx)
7262     {
7263 	dfunc_T *dfunc = ((dfunc_T *)def_functions.ga_data) + idx;
7264 
7265 	delete_def_function_contents(dfunc);
7266     }
7267 
7268     ga_clear(&def_functions);
7269 }
7270 #endif
7271 
7272 
7273 #endif // FEAT_EVAL
7274