xref: /vim-8.2.3635/src/vim9script.c (revision cb80aa2d)
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  * vim9script.c: :vim9script, :import, :export and friends
12  */
13 
14 #include "vim.h"
15 
16 #if defined(FEAT_EVAL) || defined(PROTO)
17 
18 #include "vim9.h"
19 
20     int
21 in_vim9script(void)
22 {
23     // Do not go up the stack, a ":function" inside vim9script uses legacy
24     // syntax.  "sc_version" is also set when compiling a ":def" function in
25     // legacy script.
26     return current_sctx.sc_version == SCRIPT_VERSION_VIM9;
27 }
28 
29 /*
30  * ":vim9script".
31  */
32     void
33 ex_vim9script(exarg_T *eap)
34 {
35     scriptitem_T    *si;
36 
37     if (!getline_equal(eap->getline, eap->cookie, getsourceline))
38     {
39 	emsg(_(e_vim9script_can_only_be_used_in_script));
40 	return;
41     }
42     si = SCRIPT_ITEM(current_sctx.sc_sid);
43     if (si->sn_had_command)
44     {
45 	emsg(_(e_vim9script_must_be_first_command_in_script));
46 	return;
47     }
48     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
49     si->sn_version = SCRIPT_VERSION_VIM9;
50     si->sn_had_command = TRUE;
51 
52     if (STRCMP(p_cpo, CPO_VIM) != 0)
53     {
54 	si->sn_save_cpo = vim_strsave(p_cpo);
55 	set_option_value((char_u *)"cpo", 0L, (char_u *)CPO_VIM, 0);
56     }
57 }
58 
59 /*
60  * When in Vim9 script give an error and return FAIL.
61  */
62     int
63 not_in_vim9(exarg_T *eap)
64 {
65     if (in_vim9script())
66 	switch (eap->cmdidx)
67 	{
68 	    case CMD_append:
69 	    case CMD_change:
70 	    case CMD_insert:
71 	    case CMD_t:
72 	    case CMD_xit:
73 		semsg(_(e_missing_let_str), eap->cmd);
74 		return FAIL;
75 	    default: break;
76 	}
77     return OK;
78 }
79 
80 /*
81  * ":export let Name: type"
82  * ":export const Name: type"
83  * ":export def Name(..."
84  * ":export class Name ..."
85  */
86     void
87 ex_export(exarg_T *eap)
88 {
89     if (!in_vim9script())
90     {
91 	emsg(_(e_export_can_only_be_used_in_vim9script));
92 	return;
93     }
94 
95     eap->cmd = eap->arg;
96     (void)find_ex_command(eap, NULL, lookup_scriptvar, NULL);
97     switch (eap->cmdidx)
98     {
99 	case CMD_let:
100 	case CMD_var:
101 	case CMD_final:
102 	case CMD_const:
103 	case CMD_def:
104 	// case CMD_class:
105 	    is_export = TRUE;
106 	    do_cmdline(eap->cmd, eap->getline, eap->cookie,
107 						DOCMD_VERBOSE + DOCMD_NOWAIT);
108 
109 	    // The command will reset "is_export" when exporting an item.
110 	    if (is_export)
111 	    {
112 		emsg(_(e_export_with_invalid_argument));
113 		is_export = FALSE;
114 	    }
115 	    break;
116 	default:
117 	    emsg(_(e_invalid_command_after_export));
118 	    break;
119     }
120 }
121 
122 /*
123  * Add a new imported item entry to the current script.
124  */
125     static imported_T *
126 new_imported(garray_T *gap)
127 {
128     if (ga_grow(gap, 1) == OK)
129 	return ((imported_T *)gap->ga_data + gap->ga_len++);
130     return NULL;
131 }
132 
133 /*
134  * Free all imported items in script "sid".
135  */
136     void
137 free_imports_and_script_vars(int sid)
138 {
139     scriptitem_T    *si = SCRIPT_ITEM(sid);
140     int		    idx;
141 
142     for (idx = 0; idx < si->sn_imports.ga_len; ++idx)
143     {
144 	imported_T *imp = ((imported_T *)si->sn_imports.ga_data) + idx;
145 
146 	vim_free(imp->imp_name);
147     }
148     ga_clear(&si->sn_imports);
149 
150     free_all_script_vars(si);
151 
152     clear_type_list(&si->sn_type_list);
153 }
154 
155 /*
156  * ":import Item from 'filename'"
157  * ":import Item as Alias from 'filename'"
158  * ":import {Item} from 'filename'".
159  * ":import {Item as Alias} from 'filename'"
160  * ":import {Item, Item} from 'filename'"
161  * ":import {Item, Item as Alias} from 'filename'"
162  *
163  * ":import * as Name from 'filename'"
164  */
165     void
166 ex_import(exarg_T *eap)
167 {
168     char_u	*cmd_end;
169     evalarg_T	evalarg;
170 
171     if (!getline_equal(eap->getline, eap->cookie, getsourceline))
172     {
173 	emsg(_(e_import_can_only_be_used_in_script));
174 	return;
175     }
176     fill_evalarg_from_eap(&evalarg, eap, eap->skip);
177 
178     cmd_end = handle_import(eap->arg, NULL, current_sctx.sc_sid,
179 							       &evalarg, NULL);
180     if (cmd_end != NULL)
181 	eap->nextcmd = check_nextcmd(cmd_end);
182     clear_evalarg(&evalarg, eap);
183 }
184 
185 /*
186  * Find an exported item in "sid" matching the name at "*argp".
187  * When it is a variable return the index.
188  * When it is a user function return "*ufunc".
189  * When not found returns -1 and "*ufunc" is NULL.
190  */
191     int
192 find_exported(
193 	int	    sid,
194 	char_u	    *name,
195 	ufunc_T	    **ufunc,
196 	type_T	    **type,
197 	cctx_T	    *cctx)
198 {
199     int		idx = -1;
200     svar_T	*sv;
201     scriptitem_T *script = SCRIPT_ITEM(sid);
202 
203     // find name in "script"
204     // TODO: also find script-local user function
205     idx = get_script_item_idx(sid, name, FALSE, cctx);
206     if (idx >= 0)
207     {
208 	sv = ((svar_T *)script->sn_var_vals.ga_data) + idx;
209 	if (!sv->sv_export)
210 	{
211 	    semsg(_(e_item_not_exported_in_script_str), name);
212 	    return -1;
213 	}
214 	*type = sv->sv_type;
215 	*ufunc = NULL;
216     }
217     else
218     {
219 	char_u	buffer[200];
220 	char_u	*funcname;
221 
222 	// it could be a user function.
223 	if (STRLEN(name) < sizeof(buffer) - 15)
224 	    funcname = buffer;
225 	else
226 	{
227 	    funcname = alloc(STRLEN(name) + 15);
228 	    if (funcname == NULL)
229 		return -1;
230 	}
231 	funcname[0] = K_SPECIAL;
232 	funcname[1] = KS_EXTRA;
233 	funcname[2] = (int)KE_SNR;
234 	sprintf((char *)funcname + 3, "%ld_%s", (long)sid, name);
235 	*ufunc = find_func(funcname, FALSE, NULL);
236 	if (funcname != buffer)
237 	    vim_free(funcname);
238 
239 	if (*ufunc == NULL)
240 	{
241 	    semsg(_(e_item_not_found_in_script_str), name);
242 	    return -1;
243 	}
244     }
245 
246     return idx;
247 }
248 
249 /*
250  * Handle an ":import" command and add the resulting imported_T to "gap", when
251  * not NULL, or script "import_sid" sn_imports.
252  * "cctx" is NULL at the script level.
253  * Returns a pointer to after the command or NULL in case of failure
254  */
255     char_u *
256 handle_import(
257 	char_u	    *arg_start,
258 	garray_T    *gap,
259 	int	    import_sid,
260 	evalarg_T   *evalarg,
261 	void	    *cctx)
262 {
263     char_u	*arg = arg_start;
264     char_u	*cmd_end = NULL;
265     char_u	*as_name = NULL;
266     int		ret = FAIL;
267     typval_T	tv;
268     int		sid = -1;
269     int		res;
270     garray_T	names;
271 
272     ga_init2(&names, sizeof(char_u *), 10);
273     if (*arg == '{')
274     {
275 	// "import {item, item} from ..."
276 	arg = skipwhite_and_linebreak(arg + 1, evalarg);
277 	for (;;)
278 	{
279 	    char_u  *p = arg;
280 	    int	    had_comma = FALSE;
281 
282 	    while (eval_isnamec(*arg))
283 		++arg;
284 	    if (p == arg)
285 		break;
286 	    if (ga_grow(&names, 1) == FAIL)
287 		goto erret;
288 	    ((char_u **)names.ga_data)[names.ga_len] =
289 						      vim_strnsave(p, arg - p);
290 	    ++names.ga_len;
291 	    if (*arg == ',')
292 	    {
293 		had_comma = TRUE;
294 		++arg;
295 	    }
296 	    arg = skipwhite_and_linebreak(arg, evalarg);
297 	    if (*arg == '}')
298 	    {
299 		arg = skipwhite_and_linebreak(arg + 1, evalarg);
300 		break;
301 	    }
302 	    if (!had_comma)
303 	    {
304 		emsg(_(e_missing_comma_in_import));
305 		goto erret;
306 	    }
307 	}
308 	if (names.ga_len == 0)
309 	{
310 	    emsg(_(e_syntax_error_in_import));
311 	    goto erret;
312 	}
313     }
314     else
315     {
316 	// "import Name from ..."
317 	// "import * as Name from ..."
318 	// "import item [as Name] from ..."
319 	arg = skipwhite_and_linebreak(arg, evalarg);
320 	if (arg[0] == '*' && IS_WHITE_OR_NUL(arg[1]))
321 	    arg = skipwhite_and_linebreak(arg + 1, evalarg);
322 	else if (eval_isnamec1(*arg))
323 	{
324 	    char_u  *p = arg;
325 
326 	    while (eval_isnamec(*arg))
327 		++arg;
328 	    if (ga_grow(&names, 1) == FAIL)
329 		goto erret;
330 	    ((char_u **)names.ga_data)[names.ga_len] =
331 						      vim_strnsave(p, arg - p);
332 	    ++names.ga_len;
333 	    arg = skipwhite_and_linebreak(arg, evalarg);
334 	}
335 	else
336 	{
337 	    emsg(_(e_syntax_error_in_import));
338 	    goto erret;
339 	}
340 
341 	if (STRNCMP("as", arg, 2) == 0 && IS_WHITE_OR_NUL(arg[2]))
342 	{
343 	    char_u *p;
344 
345 	    // skip over "as Name "; no line break allowed after "as"
346 	    arg = skipwhite(arg + 2);
347 	    p = arg;
348 	    if (eval_isnamec1(*arg))
349 		while (eval_isnamec(*arg))
350 		    ++arg;
351 	    if (check_defined(p, arg - p, cctx) == FAIL)
352 		goto erret;
353 	    as_name = vim_strnsave(p, arg - p);
354 	    arg = skipwhite_and_linebreak(arg, evalarg);
355 	}
356 	else if (*arg_start == '*')
357 	{
358 	    emsg(_(e_missing_as_after_star));
359 	    goto erret;
360 	}
361     }
362 
363     if (STRNCMP("from", arg, 4) != 0 || !IS_WHITE_OR_NUL(arg[4]))
364     {
365 	emsg(_(e_missing_from));
366 	goto erret;
367     }
368 
369     arg = skipwhite_and_linebreak(arg + 4, evalarg);
370     tv.v_type = VAR_UNKNOWN;
371     // TODO: should we accept any expression?
372     if (*arg == '\'')
373 	ret = eval_lit_string(&arg, &tv, TRUE);
374     else if (*arg == '"')
375 	ret = eval_string(&arg, &tv, TRUE);
376     if (ret == FAIL || tv.vval.v_string == NULL || *tv.vval.v_string == NUL)
377     {
378 	emsg(_(e_invalid_string_after_from));
379 	goto erret;
380     }
381     cmd_end = arg;
382 
383     /*
384      * find script file
385      */
386     if (*tv.vval.v_string == '.')
387     {
388 	size_t		len;
389 	scriptitem_T	*si = SCRIPT_ITEM(current_sctx.sc_sid);
390 	char_u		*tail = gettail(si->sn_name);
391 	char_u		*from_name;
392 
393 	// Relative to current script: "./name.vim", "../../name.vim".
394 	len = STRLEN(si->sn_name) - STRLEN(tail) + STRLEN(tv.vval.v_string) + 2;
395 	from_name = alloc((int)len);
396 	if (from_name == NULL)
397 	{
398 	    clear_tv(&tv);
399 	    goto erret;
400 	}
401 	vim_strncpy(from_name, si->sn_name, tail - si->sn_name);
402 	add_pathsep(from_name);
403 	STRCAT(from_name, tv.vval.v_string);
404 	simplify_filename(from_name);
405 
406 	res = do_source(from_name, FALSE, DOSO_NONE, &sid);
407 	vim_free(from_name);
408     }
409     else if (mch_isFullName(tv.vval.v_string))
410     {
411 	// Absolute path: "/tmp/name.vim"
412 	res = do_source(tv.vval.v_string, FALSE, DOSO_NONE, &sid);
413     }
414     else
415     {
416 	size_t	    len = 7 + STRLEN(tv.vval.v_string) + 1;
417 	char_u	    *from_name;
418 
419 	// Find file in "import" subdirs in 'runtimepath'.
420 	from_name = alloc((int)len);
421 	if (from_name == NULL)
422 	{
423 	    clear_tv(&tv);
424 	    goto erret;
425 	}
426 	vim_snprintf((char *)from_name, len, "import/%s", tv.vval.v_string);
427 	res = source_in_path(p_rtp, from_name, DIP_NOAFTER, &sid);
428 	vim_free(from_name);
429     }
430 
431     if (res == FAIL || sid <= 0)
432     {
433 	semsg(_(e_could_not_import_str), tv.vval.v_string);
434 	clear_tv(&tv);
435 	goto erret;
436     }
437     clear_tv(&tv);
438 
439     if (*arg_start == '*')
440     {
441 	imported_T *imported = new_imported(gap != NULL ? gap
442 					: &SCRIPT_ITEM(import_sid)->sn_imports);
443 
444 	if (imported == NULL)
445 	    goto erret;
446 	imported->imp_name = as_name;
447 	as_name = NULL;
448 	imported->imp_sid = sid;
449 	imported->imp_all = TRUE;
450     }
451     else
452     {
453 	int i;
454 
455 	arg = arg_start;
456 	if (*arg == '{')
457 	    arg = skipwhite(arg + 1);
458 	for (i = 0; i < names.ga_len; ++i)
459 	{
460 	    char_u	*name = ((char_u **)names.ga_data)[i];
461 	    int		idx;
462 	    imported_T	*imported;
463 	    ufunc_T	*ufunc = NULL;
464 	    type_T	*type;
465 
466 	    idx = find_exported(sid, name, &ufunc, &type, cctx);
467 
468 	    if (idx < 0 && ufunc == NULL)
469 		goto erret;
470 
471 	    if (check_defined(name, STRLEN(name), cctx) == FAIL)
472 		goto erret;
473 
474 	    imported = new_imported(gap != NULL ? gap
475 				       : &SCRIPT_ITEM(import_sid)->sn_imports);
476 	    if (imported == NULL)
477 		goto erret;
478 
479 	    // TODO: check for "as" following
480 	    // imported->imp_name = vim_strsave(as_name);
481 	    imported->imp_name = name;
482 	    ((char_u **)names.ga_data)[i] = NULL;
483 	    imported->imp_sid = sid;
484 	    if (idx >= 0)
485 	    {
486 		imported->imp_type = type;
487 		imported->imp_var_vals_idx = idx;
488 	    }
489 	    else
490 	    {
491 		imported->imp_type = ufunc->uf_func_type;
492 		imported->imp_funcname = ufunc->uf_name;
493 	    }
494 	}
495     }
496 erret:
497     ga_clear_strings(&names);
498     vim_free(as_name);
499     return cmd_end;
500 }
501 
502 /*
503  * Declare a script-local variable without init: "let var: type".
504  * "const" is an error since the value is missing.
505  * Returns a pointer to after the type.
506  */
507     char_u *
508 vim9_declare_scriptvar(exarg_T *eap, char_u *arg)
509 {
510     char_u	    *p;
511     char_u	    *name;
512     scriptitem_T    *si = SCRIPT_ITEM(current_sctx.sc_sid);
513     type_T	    *type;
514     int		    called_emsg_before = called_emsg;
515     typval_T	    init_tv;
516 
517     if (eap->cmdidx == CMD_final || eap->cmdidx == CMD_const)
518     {
519 	if (eap->cmdidx == CMD_final)
520 	    emsg(_(e_final_requires_a_value));
521 	else
522 	    emsg(_(e_const_requires_a_value));
523 	return arg + STRLEN(arg);
524     }
525 
526     // Check for valid starting character.
527     if (!eval_isnamec1(*arg))
528     {
529 	semsg(_(e_invarg2), arg);
530 	return arg + STRLEN(arg);
531     }
532 
533     for (p = arg + 1; *p != NUL && eval_isnamec(*p); MB_PTR_ADV(p))
534 	if (*p == ':' && (VIM_ISWHITE(p[1]) || p != arg + 1))
535 	    break;
536 
537     if (*p != ':')
538     {
539 	emsg(_(e_type_or_initialization_required));
540 	return arg + STRLEN(arg);
541     }
542     if (!VIM_ISWHITE(p[1]))
543     {
544 	semsg(_(e_white_space_required_after_str), ":");
545 	return arg + STRLEN(arg);
546     }
547     name = vim_strnsave(arg, p - arg);
548 
549     // parse type
550     p = skipwhite(p + 1);
551     type = parse_type(&p, &si->sn_type_list);
552     if (called_emsg != called_emsg_before)
553     {
554 	vim_free(name);
555 	return p;
556     }
557 
558     // Create the variable with 0/NULL value.
559     CLEAR_FIELD(init_tv);
560     if (type->tt_type == VAR_ANY)
561 	// A variable of type "any" is not possible, just use zero instead
562 	init_tv.v_type = VAR_NUMBER;
563     else
564 	init_tv.v_type = type->tt_type;
565     set_var_const(name, type, &init_tv, FALSE, 0);
566 
567     vim_free(name);
568     return p;
569 }
570 
571 /*
572  * Vim9 part of adding a script variable: add it to sn_all_vars (lookup by name
573  * with a hashtable) and sn_var_vals (lookup by index).
574  * When "type" is NULL use "tv" for the type.
575  */
576     void
577 add_vim9_script_var(dictitem_T *di, typval_T *tv, type_T *type)
578 {
579     scriptitem_T *si = SCRIPT_ITEM(current_sctx.sc_sid);
580 
581     // Store a pointer to the typval_T, so that it can be found by
582     // index instead of using a hastab lookup.
583     if (ga_grow(&si->sn_var_vals, 1) == OK)
584     {
585 	svar_T *sv = ((svar_T *)si->sn_var_vals.ga_data)
586 						      + si->sn_var_vals.ga_len;
587 	hashitem_T *hi;
588 	sallvar_T *newsav = (sallvar_T *)alloc_clear(
589 				       sizeof(sallvar_T) + STRLEN(di->di_key));
590 
591 	if (newsav == NULL)
592 	    return;
593 
594 	sv->sv_tv = &di->di_tv;
595 	if (type == NULL)
596 	    sv->sv_type = typval2type(tv, &si->sn_type_list);
597 	else
598 	    sv->sv_type = type;
599 	sv->sv_const = (di->di_flags & DI_FLAGS_LOCK) ? ASSIGN_CONST : 0;
600 	sv->sv_export = is_export;
601 	newsav->sav_var_vals_idx = si->sn_var_vals.ga_len;
602 	++si->sn_var_vals.ga_len;
603 
604 	STRCPY(&newsav->sav_key, di->di_key);
605 	sv->sv_name = newsav->sav_key;
606 	newsav->sav_di = di;
607 	newsav->sav_block_id = si->sn_current_block_id;
608 
609 	hi = hash_find(&si->sn_all_vars.dv_hashtab, newsav->sav_key);
610 	if (!HASHITEM_EMPTY(hi))
611 	{
612 	    sallvar_T *sav = HI2SAV(hi);
613 
614 	    // variable with this name exists in another block
615 	    while (sav->sav_next != NULL)
616 		sav = sav->sav_next;
617 	    sav->sav_next = newsav;
618 	}
619 	else
620 	    // new variable name
621 	    hash_add(&si->sn_all_vars.dv_hashtab, newsav->sav_key);
622 
623 	// let ex_export() know the export worked.
624 	is_export = FALSE;
625     }
626 }
627 
628 /*
629  * Hide a script variable when leaving a block.
630  * "idx" is de index in sn_var_vals.
631  * When "func_defined" is non-zero then a function was defined in this block,
632  * the variable may be accessed by it.  Otherwise the variable can be cleared.
633  */
634     void
635 hide_script_var(scriptitem_T *si, int idx, int func_defined)
636 {
637     svar_T	*sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
638     hashtab_T	*script_ht = get_script_local_ht();
639     hashtab_T	*all_ht = &si->sn_all_vars.dv_hashtab;
640     hashitem_T	*script_hi;
641     hashitem_T	*all_hi;
642 
643     // Remove a variable declared inside the block, if it still exists.
644     // If it was added in a nested block it will already have been removed.
645     // The typval is moved into the sallvar_T.
646     script_hi = hash_find(script_ht, sv->sv_name);
647     all_hi = hash_find(all_ht, sv->sv_name);
648     if (!HASHITEM_EMPTY(script_hi) && !HASHITEM_EMPTY(all_hi))
649     {
650 	dictitem_T	*di = HI2DI(script_hi);
651 	sallvar_T	*sav = HI2SAV(all_hi);
652 	sallvar_T	*sav_prev = NULL;
653 
654 	// There can be multiple entries with the same name in different
655 	// blocks, find the right one.
656 	while (sav != NULL && sav->sav_var_vals_idx != idx)
657 	{
658 	    sav_prev = sav;
659 	    sav = sav->sav_next;
660 	}
661 	if (sav != NULL)
662 	{
663 	    if (func_defined)
664 	    {
665 		// move the typval from the dictitem to the sallvar
666 		sav->sav_tv = di->di_tv;
667 		di->di_tv.v_type = VAR_UNKNOWN;
668 		sav->sav_flags = di->di_flags;
669 		sav->sav_di = NULL;
670 		sv->sv_tv = &sav->sav_tv;
671 	    }
672 	    else
673 	    {
674 		if (sav_prev == NULL)
675 		    hash_remove(all_ht, all_hi);
676 		else
677 		    sav_prev->sav_next = sav->sav_next;
678 		sv->sv_name = NULL;
679 		vim_free(sav);
680 	    }
681 	    delete_var(script_ht, script_hi);
682 	}
683     }
684 }
685 
686 /*
687  * Free the script variables from "sn_all_vars".
688  */
689     void
690 free_all_script_vars(scriptitem_T *si)
691 {
692     int		todo;
693     hashtab_T	*ht = &si->sn_all_vars.dv_hashtab;
694     hashitem_T	*hi;
695     sallvar_T	*sav;
696     sallvar_T	*sav_next;
697 
698     hash_lock(ht);
699     todo = (int)ht->ht_used;
700     for (hi = ht->ht_array; todo > 0; ++hi)
701     {
702 	if (!HASHITEM_EMPTY(hi))
703 	{
704 	    --todo;
705 
706 	    // Free the variable.  Don't remove it from the hashtab, ht_array
707 	    // might change then.  hash_clear() takes care of it later.
708 	    sav = HI2SAV(hi);
709 	    while (sav != NULL)
710 	    {
711 		sav_next = sav->sav_next;
712 		if (sav->sav_di == NULL)
713 		    clear_tv(&sav->sav_tv);
714 		vim_free(sav);
715 		sav = sav_next;
716 	    }
717 	}
718     }
719     hash_clear(ht);
720     hash_init(ht);
721 
722     ga_clear(&si->sn_var_vals);
723 }
724 
725 /*
726  * Find the script-local variable that links to "dest".
727  * Returns NULL if not found.
728  */
729     svar_T *
730 find_typval_in_script(typval_T *dest)
731 {
732     scriptitem_T    *si = SCRIPT_ITEM(current_sctx.sc_sid);
733     int		    idx;
734 
735     if (si->sn_version != SCRIPT_VERSION_VIM9)
736 	// legacy script doesn't store variable types
737 	return NULL;
738 
739     // Find the svar_T in sn_var_vals.
740     for (idx = 0; idx < si->sn_var_vals.ga_len; ++idx)
741     {
742 	svar_T    *sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
743 
744 	if (sv->sv_tv == dest)
745 	    return sv;
746     }
747     iemsg("check_script_var_type(): not found");
748     return NULL;
749 }
750 
751 /*
752  * Check if the type of script variable "dest" allows assigning "value".
753  * If needed convert "value" to a bool.
754  */
755     int
756 check_script_var_type(typval_T *dest, typval_T *value, char_u *name)
757 {
758     svar_T  *sv = find_typval_in_script(dest);
759     int	    ret;
760 
761     if (sv != NULL)
762     {
763 	if (sv->sv_const)
764 	{
765 	    semsg(_(e_readonlyvar), name);
766 	    return FAIL;
767 	}
768 	ret = check_typval_type(sv->sv_type, value, 0);
769 	if (ret == OK && need_convert_to_bool(sv->sv_type, value))
770 	{
771 	    int	val = tv2bool(value);
772 
773 	    clear_tv(value);
774 	    value->v_type = VAR_BOOL;
775 	    value->v_lock = 0;
776 	    value->vval.v_number = val ? VVAL_TRUE : VVAL_FALSE;
777 	}
778 	return ret;
779     }
780 
781     return OK; // not really
782 }
783 
784 #endif // FEAT_EVAL
785