xref: /vim-8.2.3635/src/vim9script.c (revision 4f33bc20)
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)
17 # include "vim9.h"
18 #endif
19 
20 /*
21  * Return TRUE when currently using Vim9 script syntax.
22  * Does not go up the stack, a ":function" inside vim9script uses legacy
23  * syntax.
24  */
25     int
26 in_vim9script(void)
27 {
28     // "sc_version" is also set when compiling a ":def" function in legacy
29     // script.
30     return (current_sctx.sc_version == SCRIPT_VERSION_VIM9
31 					 || (cmdmod.cmod_flags & CMOD_VIM9CMD))
32 		&& !(cmdmod.cmod_flags & CMOD_LEGACY);
33 }
34 
35 #if defined(FEAT_EVAL) || defined(PROTO)
36 /*
37  * Return TRUE if the current script is Vim9 script.
38  * This also returns TRUE in a legacy function in a Vim9 script.
39  */
40     int
41 current_script_is_vim9(void)
42 {
43     return SCRIPT_ID_VALID(current_sctx.sc_sid)
44 	    && SCRIPT_ITEM(current_sctx.sc_sid)->sn_version
45 						       == SCRIPT_VERSION_VIM9;
46 }
47 #endif
48 
49 /*
50  * ":vim9script".
51  */
52     void
53 ex_vim9script(exarg_T *eap UNUSED)
54 {
55 #ifdef FEAT_EVAL
56     int		    sid = current_sctx.sc_sid;
57     scriptitem_T    *si;
58 
59     if (!getline_equal(eap->getline, eap->cookie, getsourceline))
60     {
61 	emsg(_(e_vim9script_can_only_be_used_in_script));
62 	return;
63     }
64 
65     si = SCRIPT_ITEM(sid);
66     if (si->sn_state == SN_STATE_HAD_COMMAND)
67     {
68 	emsg(_(e_vim9script_must_be_first_command_in_script));
69 	return;
70     }
71     if (!IS_WHITE_OR_NUL(*eap->arg) && STRCMP(eap->arg, "noclear") != 0)
72     {
73 	semsg(_(e_invarg2), eap->arg);
74 	return;
75     }
76     if (si->sn_state == SN_STATE_RELOAD && IS_WHITE_OR_NUL(*eap->arg))
77     {
78 	hashtab_T	*ht = &SCRIPT_VARS(sid);
79 
80 	// Reloading a script without the "noclear" argument: clear
81 	// script-local variables and functions.
82 	hashtab_free_contents(ht);
83 	hash_init(ht);
84 	delete_script_functions(sid);
85 
86 	// old imports and script variables are no longer valid
87 	free_imports_and_script_vars(sid);
88     }
89     si->sn_state = SN_STATE_HAD_COMMAND;
90 
91     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
92     si->sn_version = SCRIPT_VERSION_VIM9;
93 
94     if (STRCMP(p_cpo, CPO_VIM) != 0)
95     {
96 	si->sn_save_cpo = vim_strsave(p_cpo);
97 	set_option_value((char_u *)"cpo", 0L, (char_u *)CPO_VIM, OPT_NO_REDRAW);
98     }
99 #else
100     // No check for this being the first command, it doesn't matter.
101     current_sctx.sc_version = SCRIPT_VERSION_VIM9;
102 #endif
103 }
104 
105 /*
106  * When in Vim9 script give an error and return FAIL.
107  */
108     int
109 not_in_vim9(exarg_T *eap)
110 {
111     if (in_vim9script())
112 	switch (eap->cmdidx)
113 	{
114 	    case CMD_k:
115 		if (eap->addr_count > 0)
116 		{
117 		    emsg(_(e_norange));
118 		    return FAIL;
119 		}
120 		// FALLTHROUGH
121 	    case CMD_append:
122 	    case CMD_change:
123 	    case CMD_insert:
124 	    case CMD_open:
125 	    case CMD_t:
126 	    case CMD_xit:
127 		semsg(_(e_command_not_supported_in_vim9_script_missing_var_str), eap->cmd);
128 		return FAIL;
129 	    default: break;
130 	}
131     return OK;
132 }
133 
134 /*
135  * Give an error message if "p" points at "#{" and return TRUE.
136  * This avoids that using a legacy style #{} dictionary leads to difficult to
137  * understand errors.
138  */
139     int
140 vim9_bad_comment(char_u *p)
141 {
142     if (p[0] == '#' && p[1] == '{' && p[2] != '{')
143     {
144 	emsg(_(e_cannot_use_hash_curly_to_start_comment));
145 	return TRUE;
146     }
147     return FALSE;
148 }
149 
150 /*
151  * Return TRUE if "p" points at a "#" not followed by one '{'.
152  * Does not check for white space.
153  */
154     int
155 vim9_comment_start(char_u *p)
156 {
157     return p[0] == '#' && (p[1] != '{' || p[2] == '{');
158 }
159 
160 #if defined(FEAT_EVAL) || defined(PROTO)
161 
162 /*
163  * "++nr" and "--nr" commands.
164  */
165     void
166 ex_incdec(exarg_T *eap)
167 {
168     char_u	*cmd = eap->cmd;
169     char_u	*nextcmd = eap->nextcmd;
170     size_t	len = STRLEN(eap->cmd) + 8;
171 
172     if (VIM_ISWHITE(cmd[2]))
173     {
174 	semsg(_(e_no_white_space_allowed_after_str_str),
175 			 eap->cmdidx == CMD_increment ? "++" : "--", eap->cmd);
176 	return;
177     }
178 
179     // This works like "nr += 1" or "nr -= 1".
180     // Add a '|' to avoid looking in the next line.
181     eap->cmd = alloc(len);
182     if (eap->cmd == NULL)
183 	return;
184     vim_snprintf((char *)eap->cmd, len, "%s %c= 1 |", cmd + 2,
185 				     eap->cmdidx == CMD_increment ? '+' : '-');
186     eap->arg = eap->cmd;
187     eap->cmdidx = CMD_var;
188     eap->nextcmd = NULL;
189     ex_let(eap);
190     vim_free(eap->cmd);
191     eap->cmd = cmd;
192     eap->nextcmd = nextcmd;
193 }
194 
195 /*
196  * ":export let Name: type"
197  * ":export const Name: type"
198  * ":export def Name(..."
199  * ":export class Name ..."
200  */
201     void
202 ex_export(exarg_T *eap)
203 {
204     if (!in_vim9script())
205     {
206 	emsg(_(e_export_can_only_be_used_in_vim9script));
207 	return;
208     }
209 
210     eap->cmd = eap->arg;
211     (void)find_ex_command(eap, NULL, lookup_scriptitem, NULL);
212     switch (eap->cmdidx)
213     {
214 	case CMD_let:
215 	case CMD_var:
216 	case CMD_final:
217 	case CMD_const:
218 	case CMD_def:
219 	// case CMD_class:
220 	    is_export = TRUE;
221 	    do_cmdline(eap->cmd, eap->getline, eap->cookie,
222 						DOCMD_VERBOSE + DOCMD_NOWAIT);
223 
224 	    // The command will reset "is_export" when exporting an item.
225 	    if (is_export)
226 	    {
227 		emsg(_(e_export_with_invalid_argument));
228 		is_export = FALSE;
229 	    }
230 	    break;
231 	default:
232 	    emsg(_(e_invalid_command_after_export));
233 	    break;
234     }
235 }
236 
237 /*
238  * Add a new imported item entry to the current script.
239  */
240     static imported_T *
241 new_imported(garray_T *gap)
242 {
243     if (ga_grow(gap, 1) == OK)
244 	return ((imported_T *)gap->ga_data + gap->ga_len++);
245     return NULL;
246 }
247 
248 /*
249  * Free all imported items in script "sid".
250  */
251     void
252 free_imports_and_script_vars(int sid)
253 {
254     scriptitem_T    *si = SCRIPT_ITEM(sid);
255     int		    idx;
256 
257     for (idx = 0; idx < si->sn_imports.ga_len; ++idx)
258     {
259 	imported_T *imp = ((imported_T *)si->sn_imports.ga_data) + idx;
260 
261 	vim_free(imp->imp_name);
262     }
263     ga_clear(&si->sn_imports);
264 
265     free_all_script_vars(si);
266 
267     clear_type_list(&si->sn_type_list);
268 }
269 
270 /*
271  * Mark all imports as possible to redefine.  Used when a script is loaded
272  * again but not cleared.
273  */
274     void
275 mark_imports_for_reload(int sid)
276 {
277     scriptitem_T    *si = SCRIPT_ITEM(sid);
278     int		    idx;
279 
280     for (idx = 0; idx < si->sn_imports.ga_len; ++idx)
281     {
282 	imported_T *imp = ((imported_T *)si->sn_imports.ga_data) + idx;
283 
284 	imp->imp_flags |= IMP_FLAGS_RELOAD;
285     }
286 }
287 
288 /*
289  * ":import Item from 'filename'"
290  * ":import Item as Alias from 'filename'"
291  * ":import {Item} from 'filename'".
292  * ":import {Item as Alias} from 'filename'"
293  * ":import {Item, Item} from 'filename'"
294  * ":import {Item, Item as Alias} from 'filename'"
295  *
296  * ":import * as Name from 'filename'"
297  */
298     void
299 ex_import(exarg_T *eap)
300 {
301     char_u	*cmd_end;
302     evalarg_T	evalarg;
303 
304     if (!getline_equal(eap->getline, eap->cookie, getsourceline))
305     {
306 	emsg(_(e_import_can_only_be_used_in_script));
307 	return;
308     }
309     fill_evalarg_from_eap(&evalarg, eap, eap->skip);
310 
311     cmd_end = handle_import(eap->arg, NULL, current_sctx.sc_sid,
312 							       &evalarg, NULL);
313     if (cmd_end != NULL)
314 	eap->nextcmd = check_nextcmd(cmd_end);
315     clear_evalarg(&evalarg, eap);
316 }
317 
318 /*
319  * Find an exported item in "sid" matching the name at "*argp".
320  * When it is a variable return the index.
321  * When it is a user function return "*ufunc".
322  * When not found returns -1 and "*ufunc" is NULL.
323  */
324     int
325 find_exported(
326 	int	    sid,
327 	char_u	    *name,
328 	ufunc_T	    **ufunc,
329 	type_T	    **type,
330 	cctx_T	    *cctx,
331 	int	    verbose)
332 {
333     int		idx = -1;
334     svar_T	*sv;
335     scriptitem_T *script = SCRIPT_ITEM(sid);
336 
337     // Find name in "script".
338     idx = get_script_item_idx(sid, name, 0, cctx);
339     if (idx >= 0)
340     {
341 	sv = ((svar_T *)script->sn_var_vals.ga_data) + idx;
342 	if (!sv->sv_export)
343 	{
344 	    if (verbose)
345 		semsg(_(e_item_not_exported_in_script_str), name);
346 	    return -1;
347 	}
348 	*type = sv->sv_type;
349 	*ufunc = NULL;
350     }
351     else
352     {
353 	char_u	buffer[200];
354 	char_u	*funcname;
355 
356 	// it could be a user function.
357 	if (STRLEN(name) < sizeof(buffer) - 15)
358 	    funcname = buffer;
359 	else
360 	{
361 	    funcname = alloc(STRLEN(name) + 15);
362 	    if (funcname == NULL)
363 		return -1;
364 	}
365 	funcname[0] = K_SPECIAL;
366 	funcname[1] = KS_EXTRA;
367 	funcname[2] = (int)KE_SNR;
368 	sprintf((char *)funcname + 3, "%ld_%s", (long)sid, name);
369 	*ufunc = find_func(funcname, FALSE, NULL);
370 	if (funcname != buffer)
371 	    vim_free(funcname);
372 
373 	if (*ufunc == NULL)
374 	{
375 	    if (verbose)
376 		semsg(_(e_item_not_found_in_script_str), name);
377 	    return -1;
378 	}
379 	else if (((*ufunc)->uf_flags & FC_EXPORT) == 0)
380 	{
381 	    if (verbose)
382 		semsg(_(e_item_not_exported_in_script_str), name);
383 	    *ufunc = NULL;
384 	    return -1;
385 	}
386     }
387 
388     return idx;
389 }
390 
391 /*
392  * Handle an ":import" command and add the resulting imported_T to "gap", when
393  * not NULL, or script "import_sid" sn_imports.
394  * "cctx" is NULL at the script level.
395  * Returns a pointer to after the command or NULL in case of failure
396  */
397     char_u *
398 handle_import(
399 	char_u	    *arg_start,
400 	garray_T    *gap,
401 	int	    import_sid,
402 	evalarg_T   *evalarg,
403 	void	    *cctx)
404 {
405     char_u	*arg = arg_start;
406     char_u	*cmd_end = NULL;
407     int		ret = FAIL;
408     typval_T	tv;
409     int		sid = -1;
410     int		res;
411     int		mult = FALSE;
412     garray_T	names;
413     garray_T	as_names;
414     long	start_lnum = SOURCING_LNUM;
415 
416     tv.v_type = VAR_UNKNOWN;
417     ga_init2(&names, sizeof(char_u *), 10);
418     ga_init2(&as_names, sizeof(char_u *), 10);
419     if (*arg == '{')
420     {
421 	// "import {item, item} from ..."
422 	mult = TRUE;
423 	arg = skipwhite_and_linebreak(arg + 1, evalarg);
424     }
425 
426     for (;;)
427     {
428 	char_u	    *p = arg;
429 	int	    had_comma = FALSE;
430 	char_u	    *as_name = NULL;
431 
432 	// accept "*" or "Name"
433 	if (!mult && arg[0] == '*' && IS_WHITE_OR_NUL(arg[1]))
434 	    ++arg;
435 	else
436 	    while (eval_isnamec(*arg))
437 		++arg;
438 	if (p == arg)
439 	    break;
440 	if (ga_grow(&names, 1) == FAIL || ga_grow(&as_names, 1) == FAIL)
441 	    goto erret;
442 	((char_u **)names.ga_data)[names.ga_len] = vim_strnsave(p, arg - p);
443 	++names.ga_len;
444 
445 	arg = skipwhite_and_linebreak(arg, evalarg);
446 	if (STRNCMP("as", arg, 2) == 0 && IS_WHITE_OR_NUL(arg[2]))
447 	{
448 	    // skip over "as Name "; no line break allowed after "as"
449 	    arg = skipwhite(arg + 2);
450 	    p = arg;
451 	    if (eval_isnamec1(*arg))
452 		while (eval_isnamec(*arg))
453 		    ++arg;
454 	    if (check_defined(p, arg - p, cctx, FALSE) == FAIL)
455 		goto erret;
456 	    as_name = vim_strnsave(p, arg - p);
457 	    arg = skipwhite_and_linebreak(arg, evalarg);
458 	}
459 	else if (*arg_start == '*')
460 	{
461 	    emsg(_(e_missing_as_after_star));
462 	    goto erret;
463 	}
464 	// without "as Name" the as_names entry is NULL
465 	((char_u **)as_names.ga_data)[as_names.ga_len] = as_name;
466 	++as_names.ga_len;
467 
468 	if (!mult)
469 	    break;
470 	if (*arg == ',')
471 	{
472 	    had_comma = TRUE;
473 	    ++arg;
474 	}
475 	arg = skipwhite_and_linebreak(arg, evalarg);
476 	if (*arg == '}')
477 	{
478 	    ++arg;
479 	    break;
480 	}
481 	if (!had_comma)
482 	{
483 	    emsg(_(e_missing_comma_in_import));
484 	    goto erret;
485 	}
486     }
487     arg = skipwhite_and_linebreak(arg, evalarg);
488 
489     if (names.ga_len == 0)
490     {
491 	emsg(_(e_syntax_error_in_import));
492 	goto erret;
493     }
494 
495     if (STRNCMP("from", arg, 4) != 0 || !IS_WHITE_OR_NUL(arg[4]))
496     {
497 	emsg(_(e_missing_from));
498 	goto erret;
499     }
500 
501     // The name of the file can be an expression, which must evaluate to a
502     // string.
503     arg = skipwhite_and_linebreak(arg + 4, evalarg);
504     ret = eval0(arg, &tv, NULL, evalarg);
505     if (ret == FAIL)
506 	goto erret;
507     if (tv.v_type != VAR_STRING
508 		       || tv.vval.v_string == NULL || *tv.vval.v_string == NUL)
509     {
510 	emsg(_(e_invalid_string_after_from));
511 	goto erret;
512     }
513     cmd_end = arg;
514 
515     // Give error messages for the start of the line.
516     SOURCING_LNUM = start_lnum;
517 
518     /*
519      * find script file
520      */
521     if (*tv.vval.v_string == '.')
522     {
523 	size_t		len;
524 	scriptitem_T	*si = SCRIPT_ITEM(current_sctx.sc_sid);
525 	char_u		*tail = gettail(si->sn_name);
526 	char_u		*from_name;
527 
528 	// Relative to current script: "./name.vim", "../../name.vim".
529 	len = STRLEN(si->sn_name) - STRLEN(tail) + STRLEN(tv.vval.v_string) + 2;
530 	from_name = alloc((int)len);
531 	if (from_name == NULL)
532 	    goto erret;
533 	vim_strncpy(from_name, si->sn_name, tail - si->sn_name);
534 	add_pathsep(from_name);
535 	STRCAT(from_name, tv.vval.v_string);
536 	simplify_filename(from_name);
537 
538 	res = do_source(from_name, FALSE, DOSO_NONE, &sid);
539 	vim_free(from_name);
540     }
541     else if (mch_isFullName(tv.vval.v_string))
542     {
543 	// Absolute path: "/tmp/name.vim"
544 	res = do_source(tv.vval.v_string, FALSE, DOSO_NONE, &sid);
545     }
546     else
547     {
548 	size_t	    len = 7 + STRLEN(tv.vval.v_string) + 1;
549 	char_u	    *from_name;
550 
551 	// Find file in "import" subdirs in 'runtimepath'.
552 	from_name = alloc((int)len);
553 	if (from_name == NULL)
554 	{
555 	    goto erret;
556 	}
557 	vim_snprintf((char *)from_name, len, "import/%s", tv.vval.v_string);
558 	res = source_in_path(p_rtp, from_name, DIP_NOAFTER, &sid);
559 	vim_free(from_name);
560     }
561 
562     if (res == FAIL || sid <= 0)
563     {
564 	semsg(_(e_could_not_import_str), tv.vval.v_string);
565 	goto erret;
566     }
567 
568     if (*arg_start == '*')
569     {
570 	imported_T  *imported;
571 	char_u	    *as_name = ((char_u **)as_names.ga_data)[0];
572 
573 	// "import * as That"
574 	imported = find_imported(as_name, STRLEN(as_name), cctx);
575 	if (imported != NULL && imported->imp_sid == sid)
576 	{
577 	    if (imported->imp_flags & IMP_FLAGS_RELOAD)
578 		// import already defined on a previous script load
579 		imported->imp_flags &= ~IMP_FLAGS_RELOAD;
580 	    else
581 	    {
582 		semsg(_(e_name_already_defined_str), as_name);
583 		goto erret;
584 	    }
585 	}
586 
587 	imported = new_imported(gap != NULL ? gap
588 					: &SCRIPT_ITEM(import_sid)->sn_imports);
589 	if (imported == NULL)
590 	    goto erret;
591 	imported->imp_name = as_name;
592 	((char_u **)as_names.ga_data)[0] = NULL;
593 	imported->imp_sid = sid;
594 	imported->imp_flags = IMP_FLAGS_STAR;
595     }
596     else
597     {
598 	int i;
599 
600 	arg = arg_start;
601 	if (*arg == '{')
602 	    arg = skipwhite(arg + 1);
603 	for (i = 0; i < names.ga_len; ++i)
604 	{
605 	    char_u	*name = ((char_u **)names.ga_data)[i];
606 	    char_u	*as_name = ((char_u **)as_names.ga_data)[i];
607 	    size_t	len = STRLEN(name);
608 	    int		idx;
609 	    imported_T	*imported;
610 	    ufunc_T	*ufunc = NULL;
611 	    type_T	*type;
612 
613 	    idx = find_exported(sid, name, &ufunc, &type, cctx, TRUE);
614 
615 	    if (idx < 0 && ufunc == NULL)
616 		goto erret;
617 
618 	    // If already imported with the same properties and the
619 	    // IMP_FLAGS_RELOAD set then we keep that entry.  Otherwise create
620 	    // a new one (and give an error for an existing import).
621 	    imported = find_imported(name, len, cctx);
622 	    if (imported != NULL
623 		    && (imported->imp_flags & IMP_FLAGS_RELOAD)
624 		    && imported->imp_sid == sid
625 		    && (idx >= 0
626 			? (equal_type(imported->imp_type, type, 0)
627 			    && imported->imp_var_vals_idx == idx)
628 			: (equal_type(imported->imp_type, ufunc->uf_func_type,
629 							     ETYPE_ARG_UNKNOWN)
630 			    && STRCMP(imported->imp_funcname,
631 							ufunc->uf_name) == 0)))
632 	    {
633 		imported->imp_flags &= ~IMP_FLAGS_RELOAD;
634 	    }
635 	    else
636 	    {
637 		if (as_name == NULL
638 			      && check_defined(name, len, cctx, FALSE) == FAIL)
639 		    goto erret;
640 
641 		imported = new_imported(gap != NULL ? gap
642 				       : &SCRIPT_ITEM(import_sid)->sn_imports);
643 		if (imported == NULL)
644 		    goto erret;
645 
646 		if (as_name == NULL)
647 		{
648 		    imported->imp_name = name;
649 		    ((char_u **)names.ga_data)[i] = NULL;
650 		}
651 		else
652 		{
653 		    // "import This as That ..."
654 		    imported->imp_name = as_name;
655 		    ((char_u **)as_names.ga_data)[i] = NULL;
656 		}
657 		imported->imp_sid = sid;
658 		if (idx >= 0)
659 		{
660 		    imported->imp_type = type;
661 		    imported->imp_var_vals_idx = idx;
662 		}
663 		else
664 		{
665 		    imported->imp_type = ufunc->uf_func_type;
666 		    imported->imp_funcname = ufunc->uf_name;
667 		}
668 	    }
669 	}
670     }
671 erret:
672     clear_tv(&tv);
673     ga_clear_strings(&names);
674     ga_clear_strings(&as_names);
675     return cmd_end;
676 }
677 
678 /*
679  * Declare a script-local variable without init: "let var: type".
680  * "const" is an error since the value is missing.
681  * Returns a pointer to after the type.
682  */
683     char_u *
684 vim9_declare_scriptvar(exarg_T *eap, char_u *arg)
685 {
686     char_u	    *p;
687     char_u	    *name;
688     scriptitem_T    *si = SCRIPT_ITEM(current_sctx.sc_sid);
689     type_T	    *type;
690     typval_T	    init_tv;
691 
692     if (eap->cmdidx == CMD_final || eap->cmdidx == CMD_const)
693     {
694 	if (eap->cmdidx == CMD_final)
695 	    emsg(_(e_final_requires_a_value));
696 	else
697 	    emsg(_(e_const_requires_a_value));
698 	return arg + STRLEN(arg);
699     }
700 
701     // Check for valid starting character.
702     if (!eval_isnamec1(*arg))
703     {
704 	semsg(_(e_invarg2), arg);
705 	return arg + STRLEN(arg);
706     }
707 
708     for (p = arg + 1; *p != NUL && eval_isnamec(*p); MB_PTR_ADV(p))
709 	if (*p == ':' && (VIM_ISWHITE(p[1]) || p != arg + 1))
710 	    break;
711 
712     if (*p != ':')
713     {
714 	emsg(_(e_type_or_initialization_required));
715 	return arg + STRLEN(arg);
716     }
717     if (!VIM_ISWHITE(p[1]))
718     {
719 	semsg(_(e_white_space_required_after_str_str), ":", p);
720 	return arg + STRLEN(arg);
721     }
722     name = vim_strnsave(arg, p - arg);
723 
724     // parse type, check for reserved name
725     p = skipwhite(p + 1);
726     type = parse_type(&p, &si->sn_type_list, TRUE);
727     if (type == NULL || check_reserved_name(name) == FAIL)
728     {
729 	vim_free(name);
730 	return p;
731     }
732 
733     // Create the variable with 0/NULL value.
734     CLEAR_FIELD(init_tv);
735     if (type->tt_type == VAR_ANY)
736 	// A variable of type "any" is not possible, just use zero instead
737 	init_tv.v_type = VAR_NUMBER;
738     else
739 	init_tv.v_type = type->tt_type;
740     set_var_const(name, type, &init_tv, FALSE, 0, 0);
741 
742     vim_free(name);
743     return p;
744 }
745 
746 /*
747  * Vim9 part of adding a script variable: add it to sn_all_vars (lookup by name
748  * with a hashtable) and sn_var_vals (lookup by index).
749  * When "create" is TRUE this is a new variable, otherwise find and update an
750  * existing variable.
751  * "flags" can have ASSIGN_FINAL or ASSIGN_CONST.
752  * When "*type" is NULL use "tv" for the type and update "*type".  If
753  * "do_member" is TRUE also use the member type, otherwise use "any".
754  */
755     void
756 update_vim9_script_var(
757 	int	    create,
758 	dictitem_T  *di,
759 	int	    flags,
760 	typval_T    *tv,
761 	type_T	    **type,
762 	int	    do_member)
763 {
764     scriptitem_T    *si = SCRIPT_ITEM(current_sctx.sc_sid);
765     hashitem_T	    *hi;
766     svar_T	    *sv = NULL;
767 
768     if (create)
769     {
770 	sallvar_T   *newsav;
771 	sallvar_T   *sav = NULL;
772 
773 	// Store a pointer to the typval_T, so that it can be found by index
774 	// instead of using a hastab lookup.
775 	if (ga_grow(&si->sn_var_vals, 1) == FAIL)
776 	    return;
777 
778 	hi = hash_find(&si->sn_all_vars.dv_hashtab, di->di_key);
779 	if (!HASHITEM_EMPTY(hi))
780 	{
781 	    // Variable with this name exists, either in this block or in
782 	    // another block.
783 	    for (sav = HI2SAV(hi); ; sav = sav->sav_next)
784 	    {
785 		if (sav->sav_block_id == si->sn_current_block_id)
786 		{
787 		    // variable defined in a loop, re-use the entry
788 		    sv = ((svar_T *)si->sn_var_vals.ga_data)
789 						       + sav->sav_var_vals_idx;
790 		    // unhide the variable
791 		    if (sv->sv_tv == &sav->sav_tv)
792 		    {
793 			clear_tv(&sav->sav_tv);
794 			sv->sv_tv = &di->di_tv;
795 			sav->sav_di = di;
796 		    }
797 		    break;
798 		}
799 		if (sav->sav_next == NULL)
800 		    break;
801 	    }
802 	}
803 
804 	if (sv == NULL)
805 	{
806 	    // Variable not defined or not defined in current block: Add a
807 	    // svar_T and create a new sallvar_T.
808 	    sv = ((svar_T *)si->sn_var_vals.ga_data) + si->sn_var_vals.ga_len;
809 	    newsav = (sallvar_T *)alloc_clear(
810 				       sizeof(sallvar_T) + STRLEN(di->di_key));
811 	    if (newsav == NULL)
812 		return;
813 
814 	    sv->sv_tv = &di->di_tv;
815 	    sv->sv_const = (flags & ASSIGN_FINAL) ? ASSIGN_FINAL
816 				   : (flags & ASSIGN_CONST) ? ASSIGN_CONST : 0;
817 	    sv->sv_export = is_export;
818 	    newsav->sav_var_vals_idx = si->sn_var_vals.ga_len;
819 	    ++si->sn_var_vals.ga_len;
820 	    STRCPY(&newsav->sav_key, di->di_key);
821 	    sv->sv_name = newsav->sav_key;
822 	    newsav->sav_di = di;
823 	    newsav->sav_block_id = si->sn_current_block_id;
824 
825 	    if (HASHITEM_EMPTY(hi))
826 		// new variable name
827 		hash_add(&si->sn_all_vars.dv_hashtab, newsav->sav_key);
828 	    else if (sav != NULL)
829 		// existing name in a new block, append to the list
830 		sav->sav_next = newsav;
831 	}
832     }
833     else
834     {
835 	sv = find_typval_in_script(&di->di_tv);
836     }
837     if (sv != NULL)
838     {
839 	if (*type == NULL)
840 	    *type = typval2type(tv, get_copyID(), &si->sn_type_list, do_member);
841 	sv->sv_type = *type;
842     }
843 
844     // let ex_export() know the export worked.
845     is_export = FALSE;
846 }
847 
848 /*
849  * Hide a script variable when leaving a block.
850  * "idx" is de index in sn_var_vals.
851  * When "func_defined" is non-zero then a function was defined in this block,
852  * the variable may be accessed by it.  Otherwise the variable can be cleared.
853  */
854     void
855 hide_script_var(scriptitem_T *si, int idx, int func_defined)
856 {
857     svar_T	*sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
858     hashtab_T	*script_ht = get_script_local_ht();
859     hashtab_T	*all_ht = &si->sn_all_vars.dv_hashtab;
860     hashitem_T	*script_hi;
861     hashitem_T	*all_hi;
862 
863     // Remove a variable declared inside the block, if it still exists.
864     // If it was added in a nested block it will already have been removed.
865     // The typval is moved into the sallvar_T.
866     script_hi = hash_find(script_ht, sv->sv_name);
867     all_hi = hash_find(all_ht, sv->sv_name);
868     if (!HASHITEM_EMPTY(script_hi) && !HASHITEM_EMPTY(all_hi))
869     {
870 	dictitem_T	*di = HI2DI(script_hi);
871 	sallvar_T	*sav = HI2SAV(all_hi);
872 	sallvar_T	*sav_prev = NULL;
873 
874 	// There can be multiple entries with the same name in different
875 	// blocks, find the right one.
876 	while (sav != NULL && sav->sav_var_vals_idx != idx)
877 	{
878 	    sav_prev = sav;
879 	    sav = sav->sav_next;
880 	}
881 	if (sav != NULL)
882 	{
883 	    if (func_defined)
884 	    {
885 		// move the typval from the dictitem to the sallvar
886 		sav->sav_tv = di->di_tv;
887 		di->di_tv.v_type = VAR_UNKNOWN;
888 		sav->sav_flags = di->di_flags;
889 		sav->sav_di = NULL;
890 		sv->sv_tv = &sav->sav_tv;
891 	    }
892 	    else
893 	    {
894 		if (sav_prev == NULL)
895 		    hash_remove(all_ht, all_hi);
896 		else
897 		    sav_prev->sav_next = sav->sav_next;
898 		sv->sv_name = NULL;
899 		vim_free(sav);
900 	    }
901 	    delete_var(script_ht, script_hi);
902 	}
903     }
904 }
905 
906 /*
907  * Free the script variables from "sn_all_vars".
908  */
909     void
910 free_all_script_vars(scriptitem_T *si)
911 {
912     int		todo;
913     hashtab_T	*ht = &si->sn_all_vars.dv_hashtab;
914     hashitem_T	*hi;
915     sallvar_T	*sav;
916     sallvar_T	*sav_next;
917 
918     hash_lock(ht);
919     todo = (int)ht->ht_used;
920     for (hi = ht->ht_array; todo > 0; ++hi)
921     {
922 	if (!HASHITEM_EMPTY(hi))
923 	{
924 	    --todo;
925 
926 	    // Free the variable.  Don't remove it from the hashtab, ht_array
927 	    // might change then.  hash_clear() takes care of it later.
928 	    sav = HI2SAV(hi);
929 	    while (sav != NULL)
930 	    {
931 		sav_next = sav->sav_next;
932 		if (sav->sav_di == NULL)
933 		    clear_tv(&sav->sav_tv);
934 		vim_free(sav);
935 		sav = sav_next;
936 	    }
937 	}
938     }
939     hash_clear(ht);
940     hash_init(ht);
941 
942     ga_clear(&si->sn_var_vals);
943 
944     // existing commands using script variable indexes are no longer valid
945     si->sn_script_seq = current_sctx.sc_seq;
946 }
947 
948 /*
949  * Find the script-local variable that links to "dest".
950  * Returns NULL if not found and give an internal error.
951  */
952     svar_T *
953 find_typval_in_script(typval_T *dest)
954 {
955     scriptitem_T    *si = SCRIPT_ITEM(current_sctx.sc_sid);
956     int		    idx;
957 
958     if (si->sn_version != SCRIPT_VERSION_VIM9)
959 	// legacy script doesn't store variable types
960 	return NULL;
961 
962     // Find the svar_T in sn_var_vals.
963     for (idx = 0; idx < si->sn_var_vals.ga_len; ++idx)
964     {
965 	svar_T    *sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
966 
967 	// If "sv_name" is NULL the variable was hidden when leaving a block,
968 	// don't check "sv_tv" then, it might be used for another variable now.
969 	if (sv->sv_name != NULL && sv->sv_tv == dest)
970 	    return sv;
971     }
972     iemsg("find_typval_in_script(): not found");
973     return NULL;
974 }
975 
976 /*
977  * Check if the type of script variable "dest" allows assigning "value".
978  * If needed convert "value" to a bool.
979  */
980     int
981 check_script_var_type(
982 	typval_T    *dest,
983 	typval_T    *value,
984 	char_u	    *name,
985 	where_T	    where)
986 {
987     svar_T  *sv = find_typval_in_script(dest);
988     int	    ret;
989 
990     if (sv != NULL)
991     {
992 	if (sv->sv_const != 0)
993 	{
994 	    semsg(_(e_cannot_change_readonly_variable_str), name);
995 	    return FAIL;
996 	}
997 	ret = check_typval_type(sv->sv_type, value, where);
998 	if (ret == OK && need_convert_to_bool(sv->sv_type, value))
999 	{
1000 	    int	val = tv2bool(value);
1001 
1002 	    clear_tv(value);
1003 	    value->v_type = VAR_BOOL;
1004 	    value->v_lock = 0;
1005 	    value->vval.v_number = val ? VVAL_TRUE : VVAL_FALSE;
1006 	}
1007 	return ret;
1008     }
1009 
1010     return OK; // not really
1011 }
1012 
1013 // words that cannot be used as a variable
1014 static char *reserved[] = {
1015     "true",
1016     "false",
1017     "null",
1018     "this",
1019     NULL
1020 };
1021 
1022     int
1023 check_reserved_name(char_u *name)
1024 {
1025     int idx;
1026 
1027     for (idx = 0; reserved[idx] != NULL; ++idx)
1028 	if (STRCMP(reserved[idx], name) == 0)
1029 	{
1030 	    semsg(_(e_cannot_use_reserved_name), name);
1031 	    return FAIL;
1032 	}
1033     return OK;
1034 }
1035 
1036 #endif // FEAT_EVAL
1037