xref: /vim-8.2.3635/src/eval.c (revision dad4473f)
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  * eval.c: Expression evaluation.
12  */
13 #define USING_FLOAT_STUFF
14 
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 NAMESPACE_CHAR	(char_u *)"abglstvw"
24 
25 /*
26  * When recursively copying lists and dicts we need to remember which ones we
27  * have done to avoid endless recursiveness.  This unique ID is used for that.
28  * The last bit is used for previous_funccal, ignored when comparing.
29  */
30 static int current_copyID = 0;
31 
32 /*
33  * Info used by a ":for" loop.
34  */
35 typedef struct
36 {
37     int		fi_semicolon;	// TRUE if ending in '; var]'
38     int		fi_varcount;	// nr of variables in the list
39     int		fi_break_count;	// nr of line breaks encountered
40     listwatch_T	fi_lw;		// keep an eye on the item used.
41     list_T	*fi_list;	// list being used
42     int		fi_bi;		// index of blob
43     blob_T	*fi_blob;	// blob being used
44     char_u	*fi_string;	// copy of string being used
45     int		fi_byte_idx;	// byte index in fi_string
46 } forinfo_T;
47 
48 static int tv_op(typval_T *tv1, typval_T *tv2, char_u  *op);
49 static int eval2(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
50 static int eval3(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
51 static int eval4(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
52 static int eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
53 static int eval6(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
54 static int eval7(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
55 static int eval7_leader(typval_T *rettv, int numeric_only, char_u *start_leader, char_u **end_leaderp);
56 
57 static int free_unref_items(int copyID);
58 static char_u *make_expanded_name(char_u *in_start, char_u *expr_start, char_u *expr_end, char_u *in_end);
59 
60 /*
61  * Return "n1" divided by "n2", taking care of dividing by zero.
62  * If "failed" is not NULL set it to TRUE when dividing by zero fails.
63  */
64 	varnumber_T
65 num_divide(varnumber_T n1, varnumber_T n2, int *failed)
66 {
67     varnumber_T	result;
68 
69     if (n2 == 0)
70     {
71 	if (in_vim9script())
72 	{
73 	    emsg(_(e_divide_by_zero));
74 	    if (failed != NULL)
75 		*failed = TRUE;
76 	}
77 	if (n1 == 0)
78 	    result = VARNUM_MIN; // similar to NaN
79 	else if (n1 < 0)
80 	    result = -VARNUM_MAX;
81 	else
82 	    result = VARNUM_MAX;
83     }
84     else
85 	result = n1 / n2;
86 
87     return result;
88 }
89 
90 /*
91  * Return "n1" modulus "n2", taking care of dividing by zero.
92  * If "failed" is not NULL set it to TRUE when dividing by zero fails.
93  */
94 	varnumber_T
95 num_modulus(varnumber_T n1, varnumber_T n2, int *failed)
96 {
97     if (n2 == 0 && in_vim9script())
98     {
99 	emsg(_(e_divide_by_zero));
100 	if (failed != NULL)
101 	    *failed = TRUE;
102     }
103     return (n2 == 0) ? 0 : (n1 % n2);
104 }
105 
106 #if defined(EBCDIC) || defined(PROTO)
107 /*
108  * Compare struct fst by function name.
109  */
110     static int
111 compare_func_name(const void *s1, const void *s2)
112 {
113     struct fst *p1 = (struct fst *)s1;
114     struct fst *p2 = (struct fst *)s2;
115 
116     return STRCMP(p1->f_name, p2->f_name);
117 }
118 
119 /*
120  * Sort the function table by function name.
121  * The sorting of the table above is ASCII dependent.
122  * On machines using EBCDIC we have to sort it.
123  */
124     static void
125 sortFunctions(void)
126 {
127     int		funcCnt = (int)(sizeof(functions) / sizeof(struct fst)) - 1;
128 
129     qsort(functions, (size_t)funcCnt, sizeof(struct fst), compare_func_name);
130 }
131 #endif
132 
133 /*
134  * Initialize the global and v: variables.
135  */
136     void
137 eval_init(void)
138 {
139     evalvars_init();
140     func_init();
141 
142 #ifdef EBCDIC
143     /*
144      * Sort the function table, to enable binary search.
145      */
146     sortFunctions();
147 #endif
148 }
149 
150 #if defined(EXITFREE) || defined(PROTO)
151     void
152 eval_clear(void)
153 {
154     evalvars_clear();
155     free_scriptnames();  // must come after evalvars_clear().
156     free_locales();
157 
158     // autoloaded script names
159     free_autoload_scriptnames();
160 
161     // unreferenced lists and dicts
162     (void)garbage_collect(FALSE);
163 
164     // functions not garbage collected
165     free_all_functions();
166 }
167 #endif
168 
169     void
170 fill_evalarg_from_eap(evalarg_T *evalarg, exarg_T *eap, int skip)
171 {
172     CLEAR_FIELD(*evalarg);
173     evalarg->eval_flags = skip ? 0 : EVAL_EVALUATE;
174     if (eap != NULL && getline_equal(eap->getline, eap->cookie, getsourceline))
175     {
176 	evalarg->eval_getline = eap->getline;
177 	evalarg->eval_cookie = eap->cookie;
178     }
179 }
180 
181 /*
182  * Top level evaluation function, returning a boolean.
183  * Sets "error" to TRUE if there was an error.
184  * Return TRUE or FALSE.
185  */
186     int
187 eval_to_bool(
188     char_u	*arg,
189     int		*error,
190     exarg_T	*eap,
191     int		skip)	    // only parse, don't execute
192 {
193     typval_T	tv;
194     varnumber_T	retval = FALSE;
195     evalarg_T	evalarg;
196 
197     fill_evalarg_from_eap(&evalarg, eap, skip);
198 
199     if (skip)
200 	++emsg_skip;
201     if (eval0(arg, &tv, eap, &evalarg) == FAIL)
202 	*error = TRUE;
203     else
204     {
205 	*error = FALSE;
206 	if (!skip)
207 	{
208 	    if (in_vim9script())
209 		retval = tv_get_bool_chk(&tv, error);
210 	    else
211 		retval = (tv_get_number_chk(&tv, error) != 0);
212 	    clear_tv(&tv);
213 	}
214     }
215     if (skip)
216 	--emsg_skip;
217     clear_evalarg(&evalarg, eap);
218 
219     return (int)retval;
220 }
221 
222 /*
223  * Call eval1() and give an error message if not done at a lower level.
224  */
225     static int
226 eval1_emsg(char_u **arg, typval_T *rettv, exarg_T *eap)
227 {
228     char_u	*start = *arg;
229     int		ret;
230     int		did_emsg_before = did_emsg;
231     int		called_emsg_before = called_emsg;
232     evalarg_T	evalarg;
233 
234     fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);
235 
236     ret = eval1(arg, rettv, &evalarg);
237     if (ret == FAIL)
238     {
239 	// Report the invalid expression unless the expression evaluation has
240 	// been cancelled due to an aborting error, an interrupt, or an
241 	// exception, or we already gave a more specific error.
242 	// Also check called_emsg for when using assert_fails().
243 	if (!aborting() && did_emsg == did_emsg_before
244 					  && called_emsg == called_emsg_before)
245 	    semsg(_(e_invexpr2), start);
246     }
247     clear_evalarg(&evalarg, eap);
248     return ret;
249 }
250 
251 /*
252  * Return whether a typval is a valid expression to pass to eval_expr_typval()
253  * or eval_expr_to_bool().  An empty string returns FALSE;
254  */
255     int
256 eval_expr_valid_arg(typval_T *tv)
257 {
258     return tv->v_type != VAR_UNKNOWN
259 	    && (tv->v_type != VAR_STRING
260 		  || (tv->vval.v_string != NULL && *tv->vval.v_string != NUL));
261 }
262 
263 /*
264  * Evaluate an expression, which can be a function, partial or string.
265  * Pass arguments "argv[argc]".
266  * Return the result in "rettv" and OK or FAIL.
267  */
268     int
269 eval_expr_typval(typval_T *expr, typval_T *argv, int argc, typval_T *rettv)
270 {
271     char_u	*s;
272     char_u	buf[NUMBUFLEN];
273     funcexe_T	funcexe;
274 
275     if (expr->v_type == VAR_FUNC)
276     {
277 	s = expr->vval.v_string;
278 	if (s == NULL || *s == NUL)
279 	    return FAIL;
280 	CLEAR_FIELD(funcexe);
281 	funcexe.evaluate = TRUE;
282 	if (call_func(s, -1, rettv, argc, argv, &funcexe) == FAIL)
283 	    return FAIL;
284     }
285     else if (expr->v_type == VAR_PARTIAL)
286     {
287 	partial_T   *partial = expr->vval.v_partial;
288 
289 	if (partial == NULL)
290 	    return FAIL;
291 
292 	if (partial->pt_func != NULL
293 			  && partial->pt_func->uf_def_status != UF_NOT_COMPILED)
294 	{
295 	    if (call_def_function(partial->pt_func, argc, argv,
296 						       partial, rettv) == FAIL)
297 		return FAIL;
298 	}
299 	else
300 	{
301 	    s = partial_name(partial);
302 	    if (s == NULL || *s == NUL)
303 		return FAIL;
304 	    CLEAR_FIELD(funcexe);
305 	    funcexe.evaluate = TRUE;
306 	    funcexe.partial = partial;
307 	    if (call_func(s, -1, rettv, argc, argv, &funcexe) == FAIL)
308 		return FAIL;
309 	}
310     }
311     else
312     {
313 	s = tv_get_string_buf_chk(expr, buf);
314 	if (s == NULL)
315 	    return FAIL;
316 	s = skipwhite(s);
317 	if (eval1_emsg(&s, rettv, NULL) == FAIL)
318 	    return FAIL;
319 	if (*skipwhite(s) != NUL)  // check for trailing chars after expr
320 	{
321 	    clear_tv(rettv);
322 	    semsg(_(e_invexpr2), s);
323 	    return FAIL;
324 	}
325     }
326     return OK;
327 }
328 
329 /*
330  * Like eval_to_bool() but using a typval_T instead of a string.
331  * Works for string, funcref and partial.
332  */
333     int
334 eval_expr_to_bool(typval_T *expr, int *error)
335 {
336     typval_T	rettv;
337     int		res;
338 
339     if (eval_expr_typval(expr, NULL, 0, &rettv) == FAIL)
340     {
341 	*error = TRUE;
342 	return FALSE;
343     }
344     res = (tv_get_bool_chk(&rettv, error) != 0);
345     clear_tv(&rettv);
346     return res;
347 }
348 
349 /*
350  * Top level evaluation function, returning a string.  If "skip" is TRUE,
351  * only parsing to "nextcmd" is done, without reporting errors.  Return
352  * pointer to allocated memory, or NULL for failure or when "skip" is TRUE.
353  */
354     char_u *
355 eval_to_string_skip(
356     char_u	*arg,
357     exarg_T	*eap,
358     int		skip)	    // only parse, don't execute
359 {
360     typval_T	tv;
361     char_u	*retval;
362     evalarg_T	evalarg;
363 
364     fill_evalarg_from_eap(&evalarg, eap, skip);
365     if (skip)
366 	++emsg_skip;
367     if (eval0(arg, &tv, eap, &evalarg) == FAIL || skip)
368 	retval = NULL;
369     else
370     {
371 	retval = vim_strsave(tv_get_string(&tv));
372 	clear_tv(&tv);
373     }
374     if (skip)
375 	--emsg_skip;
376     clear_evalarg(&evalarg, eap);
377 
378     return retval;
379 }
380 
381 /*
382  * Skip over an expression at "*pp".
383  * Return FAIL for an error, OK otherwise.
384  */
385     int
386 skip_expr(char_u **pp, evalarg_T *evalarg)
387 {
388     typval_T	rettv;
389 
390     *pp = skipwhite(*pp);
391     return eval1(pp, &rettv, evalarg);
392 }
393 
394 /*
395  * Skip over an expression at "*pp".
396  * If in Vim9 script and line breaks are encountered, the lines are
397  * concatenated.  "evalarg->eval_tofree" will be set accordingly.
398  * "arg" is advanced to just after the expression.
399  * "start" is set to the start of the expression, "end" to just after the end.
400  * Also when the expression is copied to allocated memory.
401  * Return FAIL for an error, OK otherwise.
402  */
403     int
404 skip_expr_concatenate(
405 	char_u	    **arg,
406 	char_u	    **start,
407 	char_u	    **end,
408 	evalarg_T   *evalarg)
409 {
410     typval_T	rettv;
411     int		res;
412     int		vim9script = in_vim9script();
413     garray_T    *gap = evalarg == NULL ? NULL : &evalarg->eval_ga;
414     int		save_flags = evalarg == NULL ? 0 : evalarg->eval_flags;
415     int		evaluate = evalarg == NULL
416 			       ? FALSE : (evalarg->eval_flags & EVAL_EVALUATE);
417 
418     if (vim9script && evaluate
419 	       && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL))
420     {
421 	ga_init2(gap, sizeof(char_u *), 10);
422 	// leave room for "start"
423 	if (ga_grow(gap, 1) == OK)
424 	    ++gap->ga_len;
425     }
426     *start = *arg;
427 
428     // Don't evaluate the expression.
429     if (evalarg != NULL)
430 	evalarg->eval_flags &= ~EVAL_EVALUATE;
431     *arg = skipwhite(*arg);
432     res = eval1(arg, &rettv, evalarg);
433     *end = *arg;
434     if (evalarg != NULL)
435 	evalarg->eval_flags = save_flags;
436 
437     if (vim9script && evaluate
438 	    && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL))
439     {
440 	if (evalarg->eval_ga.ga_len == 1)
441 	{
442 	    // just one line, no need to concatenate
443 	    ga_clear(gap);
444 	    gap->ga_itemsize = 0;
445 	}
446 	else
447 	{
448 	    char_u	    *p;
449 	    size_t	    endoff = STRLEN(*arg);
450 
451 	    // Line breaks encountered, concatenate all the lines.
452 	    *((char_u **)gap->ga_data) = *start;
453 	    p = ga_concat_strings(gap, "");
454 
455 	    // free the lines only when using getsourceline()
456 	    if (evalarg->eval_cookie != NULL)
457 	    {
458 		// Do not free the first line, the caller can still use it.
459 		*((char_u **)gap->ga_data) = NULL;
460 		// Do not free the last line, "arg" points into it, free it
461 		// later.
462 		vim_free(evalarg->eval_tofree);
463 		evalarg->eval_tofree =
464 				    ((char_u **)gap->ga_data)[gap->ga_len - 1];
465 		((char_u **)gap->ga_data)[gap->ga_len - 1] = NULL;
466 		ga_clear_strings(gap);
467 	    }
468 	    else
469 		ga_clear(gap);
470 	    gap->ga_itemsize = 0;
471 	    if (p == NULL)
472 		return FAIL;
473 	    *start = p;
474 	    vim_free(evalarg->eval_tofree_lambda);
475 	    evalarg->eval_tofree_lambda = p;
476 	    // Compute "end" relative to the end.
477 	    *end = *start + STRLEN(*start) - endoff;
478 	}
479     }
480 
481     return res;
482 }
483 
484 /*
485  * Convert "tv" to a string.
486  * When "convert" is TRUE convert a List into a sequence of lines and convert
487  * a Float to a String.
488  * Returns an allocated string (NULL when out of memory).
489  */
490     char_u *
491 typval2string(typval_T *tv, int convert)
492 {
493     garray_T	ga;
494     char_u	*retval;
495 #ifdef FEAT_FLOAT
496     char_u	numbuf[NUMBUFLEN];
497 #endif
498 
499     if (convert && tv->v_type == VAR_LIST)
500     {
501 	ga_init2(&ga, (int)sizeof(char), 80);
502 	if (tv->vval.v_list != NULL)
503 	{
504 	    list_join(&ga, tv->vval.v_list, (char_u *)"\n", TRUE, FALSE, 0);
505 	    if (tv->vval.v_list->lv_len > 0)
506 		ga_append(&ga, NL);
507 	}
508 	ga_append(&ga, NUL);
509 	retval = (char_u *)ga.ga_data;
510     }
511 #ifdef FEAT_FLOAT
512     else if (convert && tv->v_type == VAR_FLOAT)
513     {
514 	vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv->vval.v_float);
515 	retval = vim_strsave(numbuf);
516     }
517 #endif
518     else
519 	retval = vim_strsave(tv_get_string(tv));
520     return retval;
521 }
522 
523 /*
524  * Top level evaluation function, returning a string.  Does not handle line
525  * breaks.
526  * When "convert" is TRUE convert a List into a sequence of lines and convert
527  * a Float to a String.
528  * Return pointer to allocated memory, or NULL for failure.
529  */
530     char_u *
531 eval_to_string_eap(
532     char_u	*arg,
533     int		convert,
534     exarg_T	*eap)
535 {
536     typval_T	tv;
537     char_u	*retval;
538     evalarg_T	evalarg;
539 
540     fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);
541     if (eval0(arg, &tv, NULL, &evalarg) == FAIL)
542 	retval = NULL;
543     else
544     {
545 	retval = typval2string(&tv, convert);
546 	clear_tv(&tv);
547     }
548     clear_evalarg(&evalarg, NULL);
549 
550     return retval;
551 }
552 
553     char_u *
554 eval_to_string(
555     char_u	*arg,
556     int		convert)
557 {
558     return eval_to_string_eap(arg, convert, NULL);
559 }
560 
561 /*
562  * Call eval_to_string() without using current local variables and using
563  * textwinlock.  When "use_sandbox" is TRUE use the sandbox.
564  * Use legacy Vim script syntax.
565  */
566     char_u *
567 eval_to_string_safe(
568     char_u	*arg,
569     int		use_sandbox)
570 {
571     char_u	*retval;
572     funccal_entry_T funccal_entry;
573     int		save_sc_version = current_sctx.sc_version;
574 
575     current_sctx.sc_version = 1;
576     save_funccal(&funccal_entry);
577     if (use_sandbox)
578 	++sandbox;
579     ++textwinlock;
580     retval = eval_to_string(arg, FALSE);
581     if (use_sandbox)
582 	--sandbox;
583     --textwinlock;
584     restore_funccal();
585     current_sctx.sc_version = save_sc_version;
586     return retval;
587 }
588 
589 /*
590  * Top level evaluation function, returning a number.
591  * Evaluates "expr" silently.
592  * Returns -1 for an error.
593  */
594     varnumber_T
595 eval_to_number(char_u *expr)
596 {
597     typval_T	rettv;
598     varnumber_T	retval;
599     char_u	*p = skipwhite(expr);
600 
601     ++emsg_off;
602 
603     if (eval1(&p, &rettv, &EVALARG_EVALUATE) == FAIL)
604 	retval = -1;
605     else
606     {
607 	retval = tv_get_number_chk(&rettv, NULL);
608 	clear_tv(&rettv);
609     }
610     --emsg_off;
611 
612     return retval;
613 }
614 
615 /*
616  * Top level evaluation function.
617  * Returns an allocated typval_T with the result.
618  * Returns NULL when there is an error.
619  */
620     typval_T *
621 eval_expr(char_u *arg, exarg_T *eap)
622 {
623     typval_T	*tv;
624     evalarg_T	evalarg;
625 
626     fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);
627 
628     tv = ALLOC_ONE(typval_T);
629     if (tv != NULL && eval0(arg, tv, eap, &evalarg) == FAIL)
630 	VIM_CLEAR(tv);
631 
632     clear_evalarg(&evalarg, eap);
633     return tv;
634 }
635 
636 /*
637  * Call some Vim script function and return the result in "*rettv".
638  * Uses argv[0] to argv[argc - 1] for the function arguments.  argv[argc]
639  * should have type VAR_UNKNOWN.
640  * Returns OK or FAIL.
641  */
642     int
643 call_vim_function(
644     char_u      *func,
645     int		argc,
646     typval_T	*argv,
647     typval_T	*rettv)
648 {
649     int		ret;
650     funcexe_T	funcexe;
651 
652     rettv->v_type = VAR_UNKNOWN;		// clear_tv() uses this
653     CLEAR_FIELD(funcexe);
654     funcexe.firstline = curwin->w_cursor.lnum;
655     funcexe.lastline = curwin->w_cursor.lnum;
656     funcexe.evaluate = TRUE;
657     ret = call_func(func, -1, rettv, argc, argv, &funcexe);
658     if (ret == FAIL)
659 	clear_tv(rettv);
660 
661     return ret;
662 }
663 
664 /*
665  * Call Vim script function "func" and return the result as a number.
666  * Returns -1 when calling the function fails.
667  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
668  * have type VAR_UNKNOWN.
669  */
670     varnumber_T
671 call_func_retnr(
672     char_u      *func,
673     int		argc,
674     typval_T	*argv)
675 {
676     typval_T	rettv;
677     varnumber_T	retval;
678 
679     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
680 	return -1;
681 
682     retval = tv_get_number_chk(&rettv, NULL);
683     clear_tv(&rettv);
684     return retval;
685 }
686 
687 /*
688  * Call Vim script function like call_func_retnr() and drop the result.
689  * Returns FAIL when calling the function fails.
690  */
691     int
692 call_func_noret(
693     char_u      *func,
694     int		argc,
695     typval_T	*argv)
696 {
697     typval_T	rettv;
698 
699     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
700 	return FAIL;
701     clear_tv(&rettv);
702     return OK;
703 }
704 
705 /*
706  * Call Vim script function "func" and return the result as a string.
707  * Uses "argv" and "argc" as call_func_retnr().
708  * Returns NULL when calling the function fails.
709  */
710     void *
711 call_func_retstr(
712     char_u      *func,
713     int		argc,
714     typval_T	*argv)
715 {
716     typval_T	rettv;
717     char_u	*retval;
718 
719     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
720 	return NULL;
721 
722     retval = vim_strsave(tv_get_string(&rettv));
723     clear_tv(&rettv);
724     return retval;
725 }
726 
727 /*
728  * Call Vim script function "func" and return the result as a List.
729  * Uses "argv" and "argc" as call_func_retnr().
730  * Returns NULL when there is something wrong.
731  */
732     void *
733 call_func_retlist(
734     char_u      *func,
735     int		argc,
736     typval_T	*argv)
737 {
738     typval_T	rettv;
739 
740     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
741 	return NULL;
742 
743     if (rettv.v_type != VAR_LIST)
744     {
745 	clear_tv(&rettv);
746 	return NULL;
747     }
748 
749     return rettv.vval.v_list;
750 }
751 
752 #ifdef FEAT_FOLDING
753 /*
754  * Evaluate "arg", which is 'foldexpr'.
755  * Note: caller must set "curwin" to match "arg".
756  * Returns the foldlevel, and any character preceding it in "*cp".  Doesn't
757  * give error messages.
758  */
759     int
760 eval_foldexpr(char_u *arg, int *cp)
761 {
762     typval_T	tv;
763     varnumber_T	retval;
764     char_u	*s;
765     int		use_sandbox = was_set_insecurely((char_u *)"foldexpr",
766 								   OPT_LOCAL);
767 
768     ++emsg_off;
769     if (use_sandbox)
770 	++sandbox;
771     ++textwinlock;
772     *cp = NUL;
773     if (eval0(arg, &tv, NULL, &EVALARG_EVALUATE) == FAIL)
774 	retval = 0;
775     else
776     {
777 	// If the result is a number, just return the number.
778 	if (tv.v_type == VAR_NUMBER)
779 	    retval = tv.vval.v_number;
780 	else if (tv.v_type != VAR_STRING || tv.vval.v_string == NULL)
781 	    retval = 0;
782 	else
783 	{
784 	    // If the result is a string, check if there is a non-digit before
785 	    // the number.
786 	    s = tv.vval.v_string;
787 	    if (!VIM_ISDIGIT(*s) && *s != '-')
788 		*cp = *s++;
789 	    retval = atol((char *)s);
790 	}
791 	clear_tv(&tv);
792     }
793     --emsg_off;
794     if (use_sandbox)
795 	--sandbox;
796     --textwinlock;
797     clear_evalarg(&EVALARG_EVALUATE, NULL);
798 
799     return (int)retval;
800 }
801 #endif
802 
803 /*
804  * Get an lval: variable, Dict item or List item that can be assigned a value
805  * to: "name", "na{me}", "name[expr]", "name[expr:expr]", "name[expr][expr]",
806  * "name.key", "name.key[expr]" etc.
807  * Indexing only works if "name" is an existing List or Dictionary.
808  * "name" points to the start of the name.
809  * If "rettv" is not NULL it points to the value to be assigned.
810  * "unlet" is TRUE for ":unlet": slightly different behavior when something is
811  * wrong; must end in space or cmd separator.
812  *
813  * flags:
814  *  GLV_QUIET:       do not give error messages
815  *  GLV_READ_ONLY:   will not change the variable
816  *  GLV_NO_AUTOLOAD: do not use script autoloading
817  *
818  * Returns a pointer to just after the name, including indexes.
819  * When an evaluation error occurs "lp->ll_name" is NULL;
820  * Returns NULL for a parsing error.  Still need to free items in "lp"!
821  */
822     char_u *
823 get_lval(
824     char_u	*name,
825     typval_T	*rettv,
826     lval_T	*lp,
827     int		unlet,
828     int		skip,
829     int		flags,	    // GLV_ values
830     int		fne_flags)  // flags for find_name_end()
831 {
832     char_u	*p;
833     char_u	*expr_start, *expr_end;
834     int		cc;
835     dictitem_T	*v;
836     typval_T	var1;
837     typval_T	var2;
838     int		empty1 = FALSE;
839     listitem_T	*ni;
840     char_u	*key = NULL;
841     int		len;
842     hashtab_T	*ht = NULL;
843     int		quiet = flags & GLV_QUIET;
844     int		writing;
845 
846     // Clear everything in "lp".
847     CLEAR_POINTER(lp);
848 
849     if (skip || (flags & GLV_COMPILING))
850     {
851 	// When skipping or compiling just find the end of the name.
852 	lp->ll_name = name;
853 	lp->ll_name_end = find_name_end(name, NULL, NULL,
854 						      FNE_INCL_BR | fne_flags);
855 	return lp->ll_name_end;
856     }
857 
858     // Find the end of the name.
859     p = find_name_end(name, &expr_start, &expr_end, fne_flags);
860     lp->ll_name_end = p;
861     if (expr_start != NULL)
862     {
863 	// Don't expand the name when we already know there is an error.
864 	if (unlet && !VIM_ISWHITE(*p) && !ends_excmd(*p)
865 						    && *p != '[' && *p != '.')
866 	{
867 	    semsg(_(e_trailing_arg), p);
868 	    return NULL;
869 	}
870 
871 	lp->ll_exp_name = make_expanded_name(name, expr_start, expr_end, p);
872 	if (lp->ll_exp_name == NULL)
873 	{
874 	    // Report an invalid expression in braces, unless the
875 	    // expression evaluation has been cancelled due to an
876 	    // aborting error, an interrupt, or an exception.
877 	    if (!aborting() && !quiet)
878 	    {
879 		emsg_severe = TRUE;
880 		semsg(_(e_invarg2), name);
881 		return NULL;
882 	    }
883 	}
884 	lp->ll_name = lp->ll_exp_name;
885     }
886     else
887     {
888 	lp->ll_name = name;
889 
890 	if (in_vim9script())
891 	{
892 	    // "a: type" is declaring variable "a" with a type, not "a:".
893 	    if (p == name + 2 && p[-1] == ':')
894 	    {
895 		--p;
896 		lp->ll_name_end = p;
897 	    }
898 	    if (*p == ':')
899 	    {
900 		scriptitem_T *si = SCRIPT_ITEM(current_sctx.sc_sid);
901 		char_u	 *tp = skipwhite(p + 1);
902 
903 		// parse the type after the name
904 		lp->ll_type = parse_type(&tp, &si->sn_type_list, !quiet);
905 		if (lp->ll_type == NULL && !quiet)
906 		    return NULL;
907 		lp->ll_name_end = tp;
908 	    }
909 	}
910     }
911 
912     // Without [idx] or .key we are done.
913     if ((*p != '[' && *p != '.') || lp->ll_name == NULL)
914 	return p;
915 
916     cc = *p;
917     *p = NUL;
918     // When we would write to the variable pass &ht and prevent autoload.
919     writing = !(flags & GLV_READ_ONLY);
920     v = find_var(lp->ll_name, writing ? &ht : NULL,
921 					 (flags & GLV_NO_AUTOLOAD) || writing);
922     if (v == NULL && !quiet)
923 	semsg(_(e_undefined_variable_str), lp->ll_name);
924     *p = cc;
925     if (v == NULL)
926 	return NULL;
927 
928     if (in_vim9script() && (flags & GLV_NO_DECL) == 0)
929     {
930 	if (!quiet)
931 	    semsg(_(e_variable_already_declared), lp->ll_name);
932 	return NULL;
933     }
934 
935     /*
936      * Loop until no more [idx] or .key is following.
937      */
938     lp->ll_tv = &v->di_tv;
939     var1.v_type = VAR_UNKNOWN;
940     var2.v_type = VAR_UNKNOWN;
941     while (*p == '[' || (*p == '.' && lp->ll_tv->v_type == VAR_DICT))
942     {
943 	if (!(lp->ll_tv->v_type == VAR_LIST && lp->ll_tv->vval.v_list != NULL)
944 		&& !(lp->ll_tv->v_type == VAR_DICT)
945 		&& !(lp->ll_tv->v_type == VAR_BLOB
946 					   && lp->ll_tv->vval.v_blob != NULL))
947 	{
948 	    if (!quiet)
949 		emsg(_("E689: Can only index a List, Dictionary or Blob"));
950 	    return NULL;
951 	}
952 	if (lp->ll_range)
953 	{
954 	    if (!quiet)
955 		emsg(_("E708: [:] must come last"));
956 	    return NULL;
957 	}
958 
959 	if (in_vim9script() && lp->ll_valtype == NULL
960 		&& lp->ll_tv == &v->di_tv
961 		&& ht != NULL && ht == get_script_local_ht())
962 	{
963 	    svar_T  *sv = find_typval_in_script(lp->ll_tv);
964 
965 	    // Vim9 script local variable: get the type
966 	    if (sv != NULL)
967 		lp->ll_valtype = sv->sv_type;
968 	}
969 
970 	len = -1;
971 	if (*p == '.')
972 	{
973 	    key = p + 1;
974 	    for (len = 0; ASCII_ISALNUM(key[len]) || key[len] == '_'; ++len)
975 		;
976 	    if (len == 0)
977 	    {
978 		if (!quiet)
979 		    emsg(_(e_emptykey));
980 		return NULL;
981 	    }
982 	    p = key + len;
983 	}
984 	else
985 	{
986 	    // Get the index [expr] or the first index [expr: ].
987 	    p = skipwhite(p + 1);
988 	    if (*p == ':')
989 		empty1 = TRUE;
990 	    else
991 	    {
992 		empty1 = FALSE;
993 		if (eval1(&p, &var1, &EVALARG_EVALUATE) == FAIL)  // recursive!
994 		    return NULL;
995 		if (tv_get_string_chk(&var1) == NULL)
996 		{
997 		    // not a number or string
998 		    clear_tv(&var1);
999 		    return NULL;
1000 		}
1001 		p = skipwhite(p);
1002 	    }
1003 
1004 	    // Optionally get the second index [ :expr].
1005 	    if (*p == ':')
1006 	    {
1007 		if (lp->ll_tv->v_type == VAR_DICT)
1008 		{
1009 		    if (!quiet)
1010 			emsg(_(e_cannot_slice_dictionary));
1011 		    clear_tv(&var1);
1012 		    return NULL;
1013 		}
1014 		if (rettv != NULL
1015 			&& !(rettv->v_type == VAR_LIST
1016 						 && rettv->vval.v_list != NULL)
1017 			&& !(rettv->v_type == VAR_BLOB
1018 						&& rettv->vval.v_blob != NULL))
1019 		{
1020 		    if (!quiet)
1021 			emsg(_("E709: [:] requires a List or Blob value"));
1022 		    clear_tv(&var1);
1023 		    return NULL;
1024 		}
1025 		p = skipwhite(p + 1);
1026 		if (*p == ']')
1027 		    lp->ll_empty2 = TRUE;
1028 		else
1029 		{
1030 		    lp->ll_empty2 = FALSE;
1031 		    // recursive!
1032 		    if (eval1(&p, &var2, &EVALARG_EVALUATE) == FAIL)
1033 		    {
1034 			clear_tv(&var1);
1035 			return NULL;
1036 		    }
1037 		    if (tv_get_string_chk(&var2) == NULL)
1038 		    {
1039 			// not a number or string
1040 			clear_tv(&var1);
1041 			clear_tv(&var2);
1042 			return NULL;
1043 		    }
1044 		}
1045 		lp->ll_range = TRUE;
1046 	    }
1047 	    else
1048 		lp->ll_range = FALSE;
1049 
1050 	    if (*p != ']')
1051 	    {
1052 		if (!quiet)
1053 		    emsg(_(e_missbrac));
1054 		clear_tv(&var1);
1055 		clear_tv(&var2);
1056 		return NULL;
1057 	    }
1058 
1059 	    // Skip to past ']'.
1060 	    ++p;
1061 	}
1062 
1063 	if (lp->ll_tv->v_type == VAR_DICT)
1064 	{
1065 	    if (len == -1)
1066 	    {
1067 		// "[key]": get key from "var1"
1068 		key = tv_get_string_chk(&var1);	// is number or string
1069 		if (key == NULL)
1070 		{
1071 		    clear_tv(&var1);
1072 		    return NULL;
1073 		}
1074 	    }
1075 	    lp->ll_list = NULL;
1076 
1077 	    // a NULL dict is equivalent with an empty dict
1078 	    if (lp->ll_tv->vval.v_dict == NULL)
1079 	    {
1080 		lp->ll_tv->vval.v_dict = dict_alloc();
1081 		if (lp->ll_tv->vval.v_dict == NULL)
1082 		{
1083 		    clear_tv(&var1);
1084 		    return NULL;
1085 		}
1086 		++lp->ll_tv->vval.v_dict->dv_refcount;
1087 	    }
1088 	    lp->ll_dict = lp->ll_tv->vval.v_dict;
1089 
1090 	    lp->ll_di = dict_find(lp->ll_dict, key, len);
1091 
1092 	    // When assigning to a scope dictionary check that a function and
1093 	    // variable name is valid (only variable name unless it is l: or
1094 	    // g: dictionary). Disallow overwriting a builtin function.
1095 	    if (rettv != NULL && lp->ll_dict->dv_scope != 0)
1096 	    {
1097 		int prevval;
1098 		int wrong;
1099 
1100 		if (len != -1)
1101 		{
1102 		    prevval = key[len];
1103 		    key[len] = NUL;
1104 		}
1105 		else
1106 		    prevval = 0; // avoid compiler warning
1107 		wrong = (lp->ll_dict->dv_scope == VAR_DEF_SCOPE
1108 			       && rettv->v_type == VAR_FUNC
1109 			       && var_wrong_func_name(key, lp->ll_di == NULL))
1110 			|| !valid_varname(key, TRUE);
1111 		if (len != -1)
1112 		    key[len] = prevval;
1113 		if (wrong)
1114 		{
1115 		    clear_tv(&var1);
1116 		    return NULL;
1117 		}
1118 	    }
1119 
1120 	    if (lp->ll_valtype != NULL)
1121 		// use the type of the member
1122 		lp->ll_valtype = lp->ll_valtype->tt_member;
1123 
1124 	    if (lp->ll_di == NULL)
1125 	    {
1126 		// Can't add "v:" or "a:" variable.
1127 		if (lp->ll_dict == get_vimvar_dict()
1128 			 || &lp->ll_dict->dv_hashtab == get_funccal_args_ht())
1129 		{
1130 		    semsg(_(e_illvar), name);
1131 		    clear_tv(&var1);
1132 		    return NULL;
1133 		}
1134 
1135 		// Key does not exist in dict: may need to add it.
1136 		if (*p == '[' || *p == '.' || unlet)
1137 		{
1138 		    if (!quiet)
1139 			semsg(_(e_dictkey), key);
1140 		    clear_tv(&var1);
1141 		    return NULL;
1142 		}
1143 		if (len == -1)
1144 		    lp->ll_newkey = vim_strsave(key);
1145 		else
1146 		    lp->ll_newkey = vim_strnsave(key, len);
1147 		clear_tv(&var1);
1148 		if (lp->ll_newkey == NULL)
1149 		    p = NULL;
1150 		break;
1151 	    }
1152 	    // existing variable, need to check if it can be changed
1153 	    else if ((flags & GLV_READ_ONLY) == 0
1154 			&& (var_check_ro(lp->ll_di->di_flags, name, FALSE)
1155 			  || var_check_lock(lp->ll_di->di_flags, name, FALSE)))
1156 	    {
1157 		clear_tv(&var1);
1158 		return NULL;
1159 	    }
1160 
1161 	    clear_tv(&var1);
1162 	    lp->ll_tv = &lp->ll_di->di_tv;
1163 	}
1164 	else if (lp->ll_tv->v_type == VAR_BLOB)
1165 	{
1166 	    long bloblen = blob_len(lp->ll_tv->vval.v_blob);
1167 
1168 	    /*
1169 	     * Get the number and item for the only or first index of the List.
1170 	     */
1171 	    if (empty1)
1172 		lp->ll_n1 = 0;
1173 	    else
1174 		// is number or string
1175 		lp->ll_n1 = (long)tv_get_number(&var1);
1176 	    clear_tv(&var1);
1177 
1178 	    if (lp->ll_n1 < 0
1179 		    || lp->ll_n1 > bloblen
1180 		    || (lp->ll_range && lp->ll_n1 == bloblen))
1181 	    {
1182 		if (!quiet)
1183 		    semsg(_(e_blobidx), lp->ll_n1);
1184 		clear_tv(&var2);
1185 		return NULL;
1186 	    }
1187 	    if (lp->ll_range && !lp->ll_empty2)
1188 	    {
1189 		lp->ll_n2 = (long)tv_get_number(&var2);
1190 		clear_tv(&var2);
1191 		if (lp->ll_n2 < 0
1192 			|| lp->ll_n2 >= bloblen
1193 			|| lp->ll_n2 < lp->ll_n1)
1194 		{
1195 		    if (!quiet)
1196 			semsg(_(e_blobidx), lp->ll_n2);
1197 		    return NULL;
1198 		}
1199 	    }
1200 	    lp->ll_blob = lp->ll_tv->vval.v_blob;
1201 	    lp->ll_tv = NULL;
1202 	    break;
1203 	}
1204 	else
1205 	{
1206 	    /*
1207 	     * Get the number and item for the only or first index of the List.
1208 	     */
1209 	    if (empty1)
1210 		lp->ll_n1 = 0;
1211 	    else
1212 		// is number or string
1213 		lp->ll_n1 = (long)tv_get_number(&var1);
1214 	    clear_tv(&var1);
1215 
1216 	    lp->ll_dict = NULL;
1217 	    lp->ll_list = lp->ll_tv->vval.v_list;
1218 	    lp->ll_li = list_find_index(lp->ll_list, &lp->ll_n1);
1219 	    if (lp->ll_li == NULL)
1220 	    {
1221 		clear_tv(&var2);
1222 		if (!quiet)
1223 		    semsg(_(e_listidx), lp->ll_n1);
1224 		return NULL;
1225 	    }
1226 
1227 	    if (lp->ll_valtype != NULL)
1228 		// use the type of the member
1229 		lp->ll_valtype = lp->ll_valtype->tt_member;
1230 
1231 	    /*
1232 	     * May need to find the item or absolute index for the second
1233 	     * index of a range.
1234 	     * When no index given: "lp->ll_empty2" is TRUE.
1235 	     * Otherwise "lp->ll_n2" is set to the second index.
1236 	     */
1237 	    if (lp->ll_range && !lp->ll_empty2)
1238 	    {
1239 		lp->ll_n2 = (long)tv_get_number(&var2);
1240 						    // is number or string
1241 		clear_tv(&var2);
1242 		if (lp->ll_n2 < 0)
1243 		{
1244 		    ni = list_find(lp->ll_list, lp->ll_n2);
1245 		    if (ni == NULL)
1246 		    {
1247 			if (!quiet)
1248 			    semsg(_(e_listidx), lp->ll_n2);
1249 			return NULL;
1250 		    }
1251 		    lp->ll_n2 = list_idx_of_item(lp->ll_list, ni);
1252 		}
1253 
1254 		// Check that lp->ll_n2 isn't before lp->ll_n1.
1255 		if (lp->ll_n1 < 0)
1256 		    lp->ll_n1 = list_idx_of_item(lp->ll_list, lp->ll_li);
1257 		if (lp->ll_n2 < lp->ll_n1)
1258 		{
1259 		    if (!quiet)
1260 			semsg(_(e_listidx), lp->ll_n2);
1261 		    return NULL;
1262 		}
1263 	    }
1264 
1265 	    lp->ll_tv = &lp->ll_li->li_tv;
1266 	}
1267     }
1268 
1269     clear_tv(&var1);
1270     lp->ll_name_end = p;
1271     return p;
1272 }
1273 
1274 /*
1275  * Clear lval "lp" that was filled by get_lval().
1276  */
1277     void
1278 clear_lval(lval_T *lp)
1279 {
1280     vim_free(lp->ll_exp_name);
1281     vim_free(lp->ll_newkey);
1282 }
1283 
1284 /*
1285  * Set a variable that was parsed by get_lval() to "rettv".
1286  * "endp" points to just after the parsed name.
1287  * "op" is NULL, "+" for "+=", "-" for "-=", "*" for "*=", "/" for "/=",
1288  * "%" for "%=", "." for ".=" or "=" for "=".
1289  */
1290     void
1291 set_var_lval(
1292     lval_T	*lp,
1293     char_u	*endp,
1294     typval_T	*rettv,
1295     int		copy,
1296     int		flags,	    // ASSIGN_CONST, ASSIGN_NO_DECL
1297     char_u	*op,
1298     int		var_idx)    // index for "let [a, b] = list"
1299 {
1300     int		cc;
1301     listitem_T	*ri;
1302     dictitem_T	*di;
1303 
1304     if (lp->ll_tv == NULL)
1305     {
1306 	cc = *endp;
1307 	*endp = NUL;
1308 	if (lp->ll_blob != NULL)
1309 	{
1310 	    int	    error = FALSE, val;
1311 
1312 	    if (op != NULL && *op != '=')
1313 	    {
1314 		semsg(_(e_letwrong), op);
1315 		return;
1316 	    }
1317 	    if (value_check_lock(lp->ll_blob->bv_lock, lp->ll_name, FALSE))
1318 		return;
1319 
1320 	    if (lp->ll_range && rettv->v_type == VAR_BLOB)
1321 	    {
1322 		int	il, ir;
1323 
1324 		if (lp->ll_empty2)
1325 		    lp->ll_n2 = blob_len(lp->ll_blob) - 1;
1326 
1327 		if (lp->ll_n2 - lp->ll_n1 + 1 != blob_len(rettv->vval.v_blob))
1328 		{
1329 		    emsg(_("E972: Blob value does not have the right number of bytes"));
1330 		    return;
1331 		}
1332 		if (lp->ll_empty2)
1333 		    lp->ll_n2 = blob_len(lp->ll_blob);
1334 
1335 		ir = 0;
1336 		for (il = lp->ll_n1; il <= lp->ll_n2; il++)
1337 		    blob_set(lp->ll_blob, il,
1338 			    blob_get(rettv->vval.v_blob, ir++));
1339 	    }
1340 	    else
1341 	    {
1342 		val = (int)tv_get_number_chk(rettv, &error);
1343 		if (!error)
1344 		{
1345 		    garray_T *gap = &lp->ll_blob->bv_ga;
1346 
1347 		    // Allow for appending a byte.  Setting a byte beyond
1348 		    // the end is an error otherwise.
1349 		    if (lp->ll_n1 < gap->ga_len
1350 			    || (lp->ll_n1 == gap->ga_len
1351 				&& ga_grow(&lp->ll_blob->bv_ga, 1) == OK))
1352 		    {
1353 			blob_set(lp->ll_blob, lp->ll_n1, val);
1354 			if (lp->ll_n1 == gap->ga_len)
1355 			    ++gap->ga_len;
1356 		    }
1357 		    // error for invalid range was already given in get_lval()
1358 		}
1359 	    }
1360 	}
1361 	else if (op != NULL && *op != '=')
1362 	{
1363 	    typval_T tv;
1364 
1365 	    if (flags & (ASSIGN_CONST | ASSIGN_FINAL))
1366 	    {
1367 		emsg(_(e_cannot_mod));
1368 		*endp = cc;
1369 		return;
1370 	    }
1371 
1372 	    // handle +=, -=, *=, /=, %= and .=
1373 	    di = NULL;
1374 	    if (eval_variable(lp->ll_name, (int)STRLEN(lp->ll_name),
1375 					     &tv, &di, EVAL_VAR_VERBOSE) == OK)
1376 	    {
1377 		if ((di == NULL
1378 			 || (!var_check_ro(di->di_flags, lp->ll_name, FALSE)
1379 			   && !tv_check_lock(&di->di_tv, lp->ll_name, FALSE)))
1380 			&& tv_op(&tv, rettv, op) == OK)
1381 		    set_var(lp->ll_name, &tv, FALSE);
1382 		clear_tv(&tv);
1383 	    }
1384 	}
1385 	else
1386 	{
1387 	    if (lp->ll_type != NULL
1388 		       && check_typval_arg_type(lp->ll_type, rettv, 0) == FAIL)
1389 		return;
1390 	    set_var_const(lp->ll_name, lp->ll_type, rettv, copy,
1391 							       flags, var_idx);
1392 	}
1393 	*endp = cc;
1394     }
1395     else if (value_check_lock(lp->ll_newkey == NULL
1396 		? lp->ll_tv->v_lock
1397 		: lp->ll_tv->vval.v_dict->dv_lock, lp->ll_name, FALSE))
1398 	;
1399     else if (lp->ll_range)
1400     {
1401 	listitem_T *ll_li = lp->ll_li;
1402 	int	    ll_n1 = lp->ll_n1;
1403 
1404 	if (flags & (ASSIGN_CONST | ASSIGN_FINAL))
1405 	{
1406 	    emsg(_("E996: Cannot lock a range"));
1407 	    return;
1408 	}
1409 
1410 	/*
1411 	 * Check whether any of the list items is locked
1412 	 */
1413 	for (ri = rettv->vval.v_list->lv_first; ri != NULL && ll_li != NULL; )
1414 	{
1415 	    if (value_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
1416 		return;
1417 	    ri = ri->li_next;
1418 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == ll_n1))
1419 		break;
1420 	    ll_li = ll_li->li_next;
1421 	    ++ll_n1;
1422 	}
1423 
1424 	/*
1425 	 * Assign the List values to the list items.
1426 	 */
1427 	for (ri = rettv->vval.v_list->lv_first; ri != NULL; )
1428 	{
1429 	    if (op != NULL && *op != '=')
1430 		tv_op(&lp->ll_li->li_tv, &ri->li_tv, op);
1431 	    else
1432 	    {
1433 		clear_tv(&lp->ll_li->li_tv);
1434 		copy_tv(&ri->li_tv, &lp->ll_li->li_tv);
1435 	    }
1436 	    ri = ri->li_next;
1437 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == lp->ll_n1))
1438 		break;
1439 	    if (lp->ll_li->li_next == NULL)
1440 	    {
1441 		// Need to add an empty item.
1442 		if (list_append_number(lp->ll_list, 0) == FAIL)
1443 		{
1444 		    ri = NULL;
1445 		    break;
1446 		}
1447 	    }
1448 	    lp->ll_li = lp->ll_li->li_next;
1449 	    ++lp->ll_n1;
1450 	}
1451 	if (ri != NULL)
1452 	    emsg(_(e_list_value_has_more_items_than_targets));
1453 	else if (lp->ll_empty2
1454 		? (lp->ll_li != NULL && lp->ll_li->li_next != NULL)
1455 		: lp->ll_n1 != lp->ll_n2)
1456 	    emsg(_(e_list_value_does_not_have_enough_items));
1457     }
1458     else
1459     {
1460 	/*
1461 	 * Assign to a List or Dictionary item.
1462 	 */
1463 	if (flags & (ASSIGN_CONST | ASSIGN_FINAL))
1464 	{
1465 	    emsg(_("E996: Cannot lock a list or dict"));
1466 	    return;
1467 	}
1468 
1469 	if (lp->ll_valtype != NULL
1470 		    && check_typval_arg_type(lp->ll_valtype, rettv, 0) == FAIL)
1471 	    return;
1472 
1473 	if (lp->ll_newkey != NULL)
1474 	{
1475 	    if (op != NULL && *op != '=')
1476 	    {
1477 		semsg(_(e_letwrong), op);
1478 		return;
1479 	    }
1480 
1481 	    // Need to add an item to the Dictionary.
1482 	    di = dictitem_alloc(lp->ll_newkey);
1483 	    if (di == NULL)
1484 		return;
1485 	    if (dict_add(lp->ll_tv->vval.v_dict, di) == FAIL)
1486 	    {
1487 		vim_free(di);
1488 		return;
1489 	    }
1490 	    lp->ll_tv = &di->di_tv;
1491 	}
1492 	else if (op != NULL && *op != '=')
1493 	{
1494 	    tv_op(lp->ll_tv, rettv, op);
1495 	    return;
1496 	}
1497 	else
1498 	    clear_tv(lp->ll_tv);
1499 
1500 	/*
1501 	 * Assign the value to the variable or list item.
1502 	 */
1503 	if (copy)
1504 	    copy_tv(rettv, lp->ll_tv);
1505 	else
1506 	{
1507 	    *lp->ll_tv = *rettv;
1508 	    lp->ll_tv->v_lock = 0;
1509 	    init_tv(rettv);
1510 	}
1511     }
1512 }
1513 
1514 /*
1515  * Handle "tv1 += tv2", "tv1 -= tv2", "tv1 *= tv2", "tv1 /= tv2", "tv1 %= tv2"
1516  * and "tv1 .= tv2"
1517  * Returns OK or FAIL.
1518  */
1519     static int
1520 tv_op(typval_T *tv1, typval_T *tv2, char_u *op)
1521 {
1522     varnumber_T	n;
1523     char_u	numbuf[NUMBUFLEN];
1524     char_u	*s;
1525     int		failed = FALSE;
1526 
1527     // Can't do anything with a Funcref, Dict, v:true on the right.
1528     if (tv2->v_type != VAR_FUNC && tv2->v_type != VAR_DICT
1529 		      && tv2->v_type != VAR_BOOL && tv2->v_type != VAR_SPECIAL)
1530     {
1531 	switch (tv1->v_type)
1532 	{
1533 	    case VAR_UNKNOWN:
1534 	    case VAR_ANY:
1535 	    case VAR_VOID:
1536 	    case VAR_DICT:
1537 	    case VAR_FUNC:
1538 	    case VAR_PARTIAL:
1539 	    case VAR_BOOL:
1540 	    case VAR_SPECIAL:
1541 	    case VAR_JOB:
1542 	    case VAR_CHANNEL:
1543 		break;
1544 
1545 	    case VAR_BLOB:
1546 		if (*op != '+' || tv2->v_type != VAR_BLOB)
1547 		    break;
1548 		// BLOB += BLOB
1549 		if (tv1->vval.v_blob != NULL && tv2->vval.v_blob != NULL)
1550 		{
1551 		    blob_T  *b1 = tv1->vval.v_blob;
1552 		    blob_T  *b2 = tv2->vval.v_blob;
1553 		    int	i, len = blob_len(b2);
1554 		    for (i = 0; i < len; i++)
1555 			ga_append(&b1->bv_ga, blob_get(b2, i));
1556 		}
1557 		return OK;
1558 
1559 	    case VAR_LIST:
1560 		if (*op != '+' || tv2->v_type != VAR_LIST)
1561 		    break;
1562 		// List += List
1563 		if (tv2->vval.v_list != NULL)
1564 		{
1565 		    if (tv1->vval.v_list == NULL)
1566 		    {
1567 			tv1->vval.v_list = tv2->vval.v_list;
1568 			++tv1->vval.v_list->lv_refcount;
1569 		    }
1570 		    else
1571 			list_extend(tv1->vval.v_list, tv2->vval.v_list, NULL);
1572 		}
1573 		return OK;
1574 
1575 	    case VAR_NUMBER:
1576 	    case VAR_STRING:
1577 		if (tv2->v_type == VAR_LIST)
1578 		    break;
1579 		if (vim_strchr((char_u *)"+-*/%", *op) != NULL)
1580 		{
1581 		    // nr += nr , nr -= nr , nr *=nr , nr /= nr , nr %= nr
1582 		    n = tv_get_number(tv1);
1583 #ifdef FEAT_FLOAT
1584 		    if (tv2->v_type == VAR_FLOAT)
1585 		    {
1586 			float_T f = n;
1587 
1588 			if (*op == '%')
1589 			    break;
1590 			switch (*op)
1591 			{
1592 			    case '+': f += tv2->vval.v_float; break;
1593 			    case '-': f -= tv2->vval.v_float; break;
1594 			    case '*': f *= tv2->vval.v_float; break;
1595 			    case '/': f /= tv2->vval.v_float; break;
1596 			}
1597 			clear_tv(tv1);
1598 			tv1->v_type = VAR_FLOAT;
1599 			tv1->vval.v_float = f;
1600 		    }
1601 		    else
1602 #endif
1603 		    {
1604 			switch (*op)
1605 			{
1606 			    case '+': n += tv_get_number(tv2); break;
1607 			    case '-': n -= tv_get_number(tv2); break;
1608 			    case '*': n *= tv_get_number(tv2); break;
1609 			    case '/': n = num_divide(n, tv_get_number(tv2),
1610 							       &failed); break;
1611 			    case '%': n = num_modulus(n, tv_get_number(tv2),
1612 							       &failed); break;
1613 			}
1614 			clear_tv(tv1);
1615 			tv1->v_type = VAR_NUMBER;
1616 			tv1->vval.v_number = n;
1617 		    }
1618 		}
1619 		else
1620 		{
1621 		    if (tv2->v_type == VAR_FLOAT)
1622 			break;
1623 
1624 		    // str .= str
1625 		    s = tv_get_string(tv1);
1626 		    s = concat_str(s, tv_get_string_buf(tv2, numbuf));
1627 		    clear_tv(tv1);
1628 		    tv1->v_type = VAR_STRING;
1629 		    tv1->vval.v_string = s;
1630 		}
1631 		return failed ? FAIL : OK;
1632 
1633 	    case VAR_FLOAT:
1634 #ifdef FEAT_FLOAT
1635 		{
1636 		    float_T f;
1637 
1638 		    if (*op == '%' || *op == '.'
1639 				   || (tv2->v_type != VAR_FLOAT
1640 				    && tv2->v_type != VAR_NUMBER
1641 				    && tv2->v_type != VAR_STRING))
1642 			break;
1643 		    if (tv2->v_type == VAR_FLOAT)
1644 			f = tv2->vval.v_float;
1645 		    else
1646 			f = tv_get_number(tv2);
1647 		    switch (*op)
1648 		    {
1649 			case '+': tv1->vval.v_float += f; break;
1650 			case '-': tv1->vval.v_float -= f; break;
1651 			case '*': tv1->vval.v_float *= f; break;
1652 			case '/': tv1->vval.v_float /= f; break;
1653 		    }
1654 		}
1655 #endif
1656 		return OK;
1657 	}
1658     }
1659 
1660     semsg(_(e_letwrong), op);
1661     return FAIL;
1662 }
1663 
1664 /*
1665  * Evaluate the expression used in a ":for var in expr" command.
1666  * "arg" points to "var".
1667  * Set "*errp" to TRUE for an error, FALSE otherwise;
1668  * Return a pointer that holds the info.  Null when there is an error.
1669  */
1670     void *
1671 eval_for_line(
1672     char_u	*arg,
1673     int		*errp,
1674     exarg_T	*eap,
1675     evalarg_T	*evalarg)
1676 {
1677     forinfo_T	*fi;
1678     char_u	*expr;
1679     typval_T	tv;
1680     list_T	*l;
1681     int		skip = !(evalarg->eval_flags & EVAL_EVALUATE);
1682 
1683     *errp = TRUE;	// default: there is an error
1684 
1685     fi = ALLOC_CLEAR_ONE(forinfo_T);
1686     if (fi == NULL)
1687 	return NULL;
1688 
1689     expr = skip_var_list(arg, TRUE, &fi->fi_varcount, &fi->fi_semicolon, FALSE);
1690     if (expr == NULL)
1691 	return fi;
1692 
1693     expr = skipwhite_and_linebreak(expr, evalarg);
1694     if (expr[0] != 'i' || expr[1] != 'n'
1695 				  || !(expr[2] == NUL || VIM_ISWHITE(expr[2])))
1696     {
1697 	emsg(_(e_missing_in));
1698 	return fi;
1699     }
1700 
1701     if (skip)
1702 	++emsg_skip;
1703     expr = skipwhite_and_linebreak(expr + 2, evalarg);
1704     if (eval0(expr, &tv, eap, evalarg) == OK)
1705     {
1706 	*errp = FALSE;
1707 	if (!skip)
1708 	{
1709 	    if (tv.v_type == VAR_LIST)
1710 	    {
1711 		l = tv.vval.v_list;
1712 		if (l == NULL)
1713 		{
1714 		    // a null list is like an empty list: do nothing
1715 		    clear_tv(&tv);
1716 		}
1717 		else
1718 		{
1719 		    // Need a real list here.
1720 		    CHECK_LIST_MATERIALIZE(l);
1721 
1722 		    // No need to increment the refcount, it's already set for
1723 		    // the list being used in "tv".
1724 		    fi->fi_list = l;
1725 		    list_add_watch(l, &fi->fi_lw);
1726 		    fi->fi_lw.lw_item = l->lv_first;
1727 		}
1728 	    }
1729 	    else if (tv.v_type == VAR_BLOB)
1730 	    {
1731 		fi->fi_bi = 0;
1732 		if (tv.vval.v_blob != NULL)
1733 		{
1734 		    typval_T btv;
1735 
1736 		    // Make a copy, so that the iteration still works when the
1737 		    // blob is changed.
1738 		    blob_copy(tv.vval.v_blob, &btv);
1739 		    fi->fi_blob = btv.vval.v_blob;
1740 		}
1741 		clear_tv(&tv);
1742 	    }
1743 	    else if (tv.v_type == VAR_STRING)
1744 	    {
1745 		fi->fi_byte_idx = 0;
1746 		fi->fi_string = tv.vval.v_string;
1747 		tv.vval.v_string = NULL;
1748 		if (fi->fi_string == NULL)
1749 		    fi->fi_string = vim_strsave((char_u *)"");
1750 	    }
1751 	    else
1752 	    {
1753 		emsg(_(e_listreq));
1754 		clear_tv(&tv);
1755 	    }
1756 	}
1757     }
1758     if (skip)
1759 	--emsg_skip;
1760     fi->fi_break_count = evalarg->eval_break_count;
1761 
1762     return fi;
1763 }
1764 
1765 /*
1766  * Used when looping over a :for line, skip the "in expr" part.
1767  */
1768     void
1769 skip_for_lines(void *fi_void, evalarg_T *evalarg)
1770 {
1771     forinfo_T	*fi = (forinfo_T *)fi_void;
1772     int		i;
1773 
1774     for (i = 0; i < fi->fi_break_count; ++i)
1775 	eval_next_line(evalarg);
1776 }
1777 
1778 /*
1779  * Use the first item in a ":for" list.  Advance to the next.
1780  * Assign the values to the variable (list).  "arg" points to the first one.
1781  * Return TRUE when a valid item was found, FALSE when at end of list or
1782  * something wrong.
1783  */
1784     int
1785 next_for_item(void *fi_void, char_u *arg)
1786 {
1787     forinfo_T	*fi = (forinfo_T *)fi_void;
1788     int		result;
1789     int		flag = in_vim9script() ? ASSIGN_DECL : 0;
1790     listitem_T	*item;
1791 
1792     if (fi->fi_blob != NULL)
1793     {
1794 	typval_T	tv;
1795 
1796 	if (fi->fi_bi >= blob_len(fi->fi_blob))
1797 	    return FALSE;
1798 	tv.v_type = VAR_NUMBER;
1799 	tv.v_lock = VAR_FIXED;
1800 	tv.vval.v_number = blob_get(fi->fi_blob, fi->fi_bi);
1801 	++fi->fi_bi;
1802 	return ex_let_vars(arg, &tv, TRUE, fi->fi_semicolon,
1803 					    fi->fi_varcount, flag, NULL) == OK;
1804     }
1805 
1806     if (fi->fi_string != NULL)
1807     {
1808 	typval_T	tv;
1809 	int		len;
1810 
1811 	len = mb_ptr2len(fi->fi_string + fi->fi_byte_idx);
1812 	if (len == 0)
1813 	    return FALSE;
1814 	tv.v_type = VAR_STRING;
1815 	tv.v_lock = VAR_FIXED;
1816 	tv.vval.v_string = vim_strnsave(fi->fi_string + fi->fi_byte_idx, len);
1817 	fi->fi_byte_idx += len;
1818 	result = ex_let_vars(arg, &tv, TRUE, fi->fi_semicolon,
1819 					    fi->fi_varcount, flag, NULL) == OK;
1820 	vim_free(tv.vval.v_string);
1821 	return result;
1822     }
1823 
1824     item = fi->fi_lw.lw_item;
1825     if (item == NULL)
1826 	result = FALSE;
1827     else
1828     {
1829 	fi->fi_lw.lw_item = item->li_next;
1830 	result = (ex_let_vars(arg, &item->li_tv, TRUE, fi->fi_semicolon,
1831 					   fi->fi_varcount, flag, NULL) == OK);
1832     }
1833     return result;
1834 }
1835 
1836 /*
1837  * Free the structure used to store info used by ":for".
1838  */
1839     void
1840 free_for_info(void *fi_void)
1841 {
1842     forinfo_T    *fi = (forinfo_T *)fi_void;
1843 
1844     if (fi == NULL)
1845 	return;
1846     if (fi->fi_list != NULL)
1847     {
1848 	list_rem_watch(fi->fi_list, &fi->fi_lw);
1849 	list_unref(fi->fi_list);
1850     }
1851     else if (fi->fi_blob != NULL)
1852 	blob_unref(fi->fi_blob);
1853     else
1854 	vim_free(fi->fi_string);
1855     vim_free(fi);
1856 }
1857 
1858     void
1859 set_context_for_expression(
1860     expand_T	*xp,
1861     char_u	*arg,
1862     cmdidx_T	cmdidx)
1863 {
1864     int		has_expr = cmdidx != CMD_let && cmdidx != CMD_var;
1865     int		c;
1866     char_u	*p;
1867 
1868     if (cmdidx == CMD_let || cmdidx == CMD_var
1869 				 || cmdidx == CMD_const || cmdidx == CMD_final)
1870     {
1871 	xp->xp_context = EXPAND_USER_VARS;
1872 	if (vim_strpbrk(arg, (char_u *)"\"'+-*/%.=!?~|&$([<>,#") == NULL)
1873 	{
1874 	    // ":let var1 var2 ...": find last space.
1875 	    for (p = arg + STRLEN(arg); p >= arg; )
1876 	    {
1877 		xp->xp_pattern = p;
1878 		MB_PTR_BACK(arg, p);
1879 		if (VIM_ISWHITE(*p))
1880 		    break;
1881 	    }
1882 	    return;
1883 	}
1884     }
1885     else
1886 	xp->xp_context = cmdidx == CMD_call ? EXPAND_FUNCTIONS
1887 							  : EXPAND_EXPRESSION;
1888     while ((xp->xp_pattern = vim_strpbrk(arg,
1889 				  (char_u *)"\"'+-*/%.=!?~|&$([<>,#")) != NULL)
1890     {
1891 	c = *xp->xp_pattern;
1892 	if (c == '&')
1893 	{
1894 	    c = xp->xp_pattern[1];
1895 	    if (c == '&')
1896 	    {
1897 		++xp->xp_pattern;
1898 		xp->xp_context = has_expr ? EXPAND_EXPRESSION : EXPAND_NOTHING;
1899 	    }
1900 	    else if (c != ' ')
1901 	    {
1902 		xp->xp_context = EXPAND_SETTINGS;
1903 		if ((c == 'l' || c == 'g') && xp->xp_pattern[2] == ':')
1904 		    xp->xp_pattern += 2;
1905 
1906 	    }
1907 	}
1908 	else if (c == '$')
1909 	{
1910 	    // environment variable
1911 	    xp->xp_context = EXPAND_ENV_VARS;
1912 	}
1913 	else if (c == '=')
1914 	{
1915 	    has_expr = TRUE;
1916 	    xp->xp_context = EXPAND_EXPRESSION;
1917 	}
1918 	else if (c == '#'
1919 		&& xp->xp_context == EXPAND_EXPRESSION)
1920 	{
1921 	    // Autoload function/variable contains '#'.
1922 	    break;
1923 	}
1924 	else if ((c == '<' || c == '#')
1925 		&& xp->xp_context == EXPAND_FUNCTIONS
1926 		&& vim_strchr(xp->xp_pattern, '(') == NULL)
1927 	{
1928 	    // Function name can start with "<SNR>" and contain '#'.
1929 	    break;
1930 	}
1931 	else if (has_expr)
1932 	{
1933 	    if (c == '"')	    // string
1934 	    {
1935 		while ((c = *++xp->xp_pattern) != NUL && c != '"')
1936 		    if (c == '\\' && xp->xp_pattern[1] != NUL)
1937 			++xp->xp_pattern;
1938 		xp->xp_context = EXPAND_NOTHING;
1939 	    }
1940 	    else if (c == '\'')	    // literal string
1941 	    {
1942 		// Trick: '' is like stopping and starting a literal string.
1943 		while ((c = *++xp->xp_pattern) != NUL && c != '\'')
1944 		    /* skip */ ;
1945 		xp->xp_context = EXPAND_NOTHING;
1946 	    }
1947 	    else if (c == '|')
1948 	    {
1949 		if (xp->xp_pattern[1] == '|')
1950 		{
1951 		    ++xp->xp_pattern;
1952 		    xp->xp_context = EXPAND_EXPRESSION;
1953 		}
1954 		else
1955 		    xp->xp_context = EXPAND_COMMANDS;
1956 	    }
1957 	    else
1958 		xp->xp_context = EXPAND_EXPRESSION;
1959 	}
1960 	else
1961 	    // Doesn't look like something valid, expand as an expression
1962 	    // anyway.
1963 	    xp->xp_context = EXPAND_EXPRESSION;
1964 	arg = xp->xp_pattern;
1965 	if (*arg != NUL)
1966 	    while ((c = *++arg) != NUL && (c == ' ' || c == '\t'))
1967 		/* skip */ ;
1968     }
1969 
1970     // ":exe one two" completes "two"
1971     if ((cmdidx == CMD_execute
1972 		|| cmdidx == CMD_echo
1973 		|| cmdidx == CMD_echon
1974 		|| cmdidx == CMD_echomsg)
1975 	    && xp->xp_context == EXPAND_EXPRESSION)
1976     {
1977 	for (;;)
1978 	{
1979 	    char_u *n = skiptowhite(arg);
1980 
1981 	    if (n == arg || IS_WHITE_OR_NUL(*skipwhite(n)))
1982 		break;
1983 	    arg = skipwhite(n);
1984 	}
1985     }
1986 
1987     xp->xp_pattern = arg;
1988 }
1989 
1990 /*
1991  * Return TRUE if "pat" matches "text".
1992  * Does not use 'cpo' and always uses 'magic'.
1993  */
1994     int
1995 pattern_match(char_u *pat, char_u *text, int ic)
1996 {
1997     int		matches = FALSE;
1998     char_u	*save_cpo;
1999     regmatch_T	regmatch;
2000 
2001     // avoid 'l' flag in 'cpoptions'
2002     save_cpo = p_cpo;
2003     p_cpo = empty_option;
2004     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
2005     if (regmatch.regprog != NULL)
2006     {
2007 	regmatch.rm_ic = ic;
2008 	matches = vim_regexec_nl(&regmatch, text, (colnr_T)0);
2009 	vim_regfree(regmatch.regprog);
2010     }
2011     p_cpo = save_cpo;
2012     return matches;
2013 }
2014 
2015 /*
2016  * Handle a name followed by "(".  Both for just "name(arg)" and for
2017  * "expr->name(arg)".
2018  * Returns OK or FAIL.
2019  */
2020     static int
2021 eval_func(
2022 	char_u	    **arg,	// points to "(", will be advanced
2023 	evalarg_T   *evalarg,
2024 	char_u	    *name,
2025 	int	    name_len,
2026 	typval_T    *rettv,
2027 	int	    flags,
2028 	typval_T    *basetv)	// "expr" for "expr->name(arg)"
2029 {
2030     int		evaluate = flags & EVAL_EVALUATE;
2031     char_u	*s = name;
2032     int		len = name_len;
2033     partial_T	*partial;
2034     int		ret = OK;
2035     type_T	*type = NULL;
2036 
2037     if (!evaluate)
2038 	check_vars(s, len);
2039 
2040     // If "s" is the name of a variable of type VAR_FUNC
2041     // use its contents.
2042     s = deref_func_name(s, &len, &partial,
2043 				    in_vim9script() ? &type : NULL, !evaluate);
2044 
2045     // Need to make a copy, in case evaluating the arguments makes
2046     // the name invalid.
2047     s = vim_strsave(s);
2048     if (s == NULL || (flags & EVAL_CONSTANT))
2049 	ret = FAIL;
2050     else
2051     {
2052 	funcexe_T funcexe;
2053 
2054 	// Invoke the function.
2055 	CLEAR_FIELD(funcexe);
2056 	funcexe.firstline = curwin->w_cursor.lnum;
2057 	funcexe.lastline = curwin->w_cursor.lnum;
2058 	funcexe.evaluate = evaluate;
2059 	funcexe.partial = partial;
2060 	funcexe.basetv = basetv;
2061 	funcexe.check_type = type;
2062 	ret = get_func_tv(s, len, rettv, arg, evalarg, &funcexe);
2063     }
2064     vim_free(s);
2065 
2066     // If evaluate is FALSE rettv->v_type was not set in
2067     // get_func_tv, but it's needed in handle_subscript() to parse
2068     // what follows. So set it here.
2069     if (rettv->v_type == VAR_UNKNOWN && !evaluate && **arg == '(')
2070     {
2071 	rettv->vval.v_string = NULL;
2072 	rettv->v_type = VAR_FUNC;
2073     }
2074 
2075     // Stop the expression evaluation when immediately
2076     // aborting on error, or when an interrupt occurred or
2077     // an exception was thrown but not caught.
2078     if (evaluate && aborting())
2079     {
2080 	if (ret == OK)
2081 	    clear_tv(rettv);
2082 	ret = FAIL;
2083     }
2084     return ret;
2085 }
2086 
2087 /*
2088  * Get the next line source line without advancing.  But do skip over comment
2089  * lines.
2090  */
2091     static char_u *
2092 getline_peek_skip_comments(evalarg_T *evalarg)
2093 {
2094     for (;;)
2095     {
2096 	char_u *next = getline_peek(evalarg->eval_getline,
2097 							 evalarg->eval_cookie);
2098 	char_u *p;
2099 
2100 	if (next == NULL)
2101 	    break;
2102 	p = skipwhite(next);
2103 	if (*p != NUL && !vim9_comment_start(p))
2104 	    return next;
2105 	(void)eval_next_line(evalarg);
2106     }
2107     return NULL;
2108 }
2109 
2110 /*
2111  * If inside Vim9 script, "arg" points to the end of a line (ignoring a #
2112  * comment) and there is a next line, return the next line (skipping blanks)
2113  * and set "getnext".
2114  * Otherwise just return "arg" unmodified and set "getnext" to FALSE.
2115  * "arg" must point somewhere inside a line, not at the start.
2116  */
2117     char_u *
2118 eval_next_non_blank(char_u *arg, evalarg_T *evalarg, int *getnext)
2119 {
2120     char_u *p = skipwhite(arg);
2121 
2122     *getnext = FALSE;
2123     if (in_vim9script()
2124 	    && evalarg != NULL
2125 	    && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL)
2126 	    && (*p == NUL || (VIM_ISWHITE(p[-1]) && vim9_comment_start(p))))
2127     {
2128 	char_u *next;
2129 
2130 	if (evalarg->eval_cookie != NULL)
2131 	    next = getline_peek_skip_comments(evalarg);
2132 	else
2133 	    next = peek_next_line_from_context(evalarg->eval_cctx);
2134 
2135 	if (next != NULL)
2136 	{
2137 	    *getnext = TRUE;
2138 	    return skipwhite(next);
2139 	}
2140     }
2141     return p;
2142 }
2143 
2144 /*
2145  * To be called after eval_next_non_blank() sets "getnext" to TRUE.
2146  */
2147     char_u *
2148 eval_next_line(evalarg_T *evalarg)
2149 {
2150     garray_T	*gap = &evalarg->eval_ga;
2151     char_u	*line;
2152 
2153     if (evalarg->eval_cookie != NULL)
2154 	line = evalarg->eval_getline(0, evalarg->eval_cookie, 0,
2155 							   GETLINE_CONCAT_ALL);
2156     else
2157 	line = next_line_from_context(evalarg->eval_cctx, TRUE);
2158     ++evalarg->eval_break_count;
2159     if (gap->ga_itemsize > 0 && ga_grow(gap, 1) == OK)
2160     {
2161 	// Going to concatenate the lines after parsing.
2162 	((char_u **)gap->ga_data)[gap->ga_len] = line;
2163 	++gap->ga_len;
2164     }
2165     else if (evalarg->eval_cookie != NULL)
2166     {
2167 	vim_free(evalarg->eval_tofree);
2168 	evalarg->eval_tofree = line;
2169     }
2170     return skipwhite(line);
2171 }
2172 
2173 /*
2174  * Call eval_next_non_blank() and get the next line if needed.
2175  */
2176     char_u *
2177 skipwhite_and_linebreak(char_u *arg, evalarg_T *evalarg)
2178 {
2179     int	    getnext;
2180     char_u  *p = skipwhite(arg);
2181 
2182     if (evalarg == NULL)
2183 	return skipwhite(arg);
2184     eval_next_non_blank(p, evalarg, &getnext);
2185     if (getnext)
2186 	return eval_next_line(evalarg);
2187     return p;
2188 }
2189 
2190 /*
2191  * After using "evalarg" filled from "eap": free the memory.
2192  */
2193     void
2194 clear_evalarg(evalarg_T *evalarg, exarg_T *eap)
2195 {
2196     if (evalarg != NULL)
2197     {
2198 	if (evalarg->eval_tofree != NULL)
2199 	{
2200 	    if (eap != NULL)
2201 	    {
2202 		// We may need to keep the original command line, e.g. for
2203 		// ":let" it has the variable names.  But we may also need the
2204 		// new one, "nextcmd" points into it.  Keep both.
2205 		vim_free(eap->cmdline_tofree);
2206 		eap->cmdline_tofree = *eap->cmdlinep;
2207 		*eap->cmdlinep = evalarg->eval_tofree;
2208 	    }
2209 	    else
2210 		vim_free(evalarg->eval_tofree);
2211 	    evalarg->eval_tofree = NULL;
2212 	}
2213 
2214 	VIM_CLEAR(evalarg->eval_tofree_cmdline);
2215 	VIM_CLEAR(evalarg->eval_tofree_lambda);
2216     }
2217 }
2218 
2219 /*
2220  * The "evaluate" argument: When FALSE, the argument is only parsed but not
2221  * executed.  The function may return OK, but the rettv will be of type
2222  * VAR_UNKNOWN.  The function still returns FAIL for a syntax error.
2223  */
2224 
2225 /*
2226  * Handle zero level expression.
2227  * This calls eval1() and handles error message and nextcmd.
2228  * Put the result in "rettv" when returning OK and "evaluate" is TRUE.
2229  * Note: "rettv.v_lock" is not set.
2230  * "evalarg" can be NULL, EVALARG_EVALUATE or a pointer.
2231  * Return OK or FAIL.
2232  */
2233     int
2234 eval0(
2235     char_u	*arg,
2236     typval_T	*rettv,
2237     exarg_T	*eap,
2238     evalarg_T	*evalarg)
2239 {
2240     int		ret;
2241     char_u	*p;
2242     int		did_emsg_before = did_emsg;
2243     int		called_emsg_before = called_emsg;
2244     int		flags = evalarg == NULL ? 0 : evalarg->eval_flags;
2245 
2246     p = skipwhite(arg);
2247     ret = eval1(&p, rettv, evalarg);
2248     p = skipwhite(p);
2249 
2250     if (ret == FAIL || !ends_excmd2(arg, p))
2251     {
2252 	if (ret != FAIL)
2253 	    clear_tv(rettv);
2254 	/*
2255 	 * Report the invalid expression unless the expression evaluation has
2256 	 * been cancelled due to an aborting error, an interrupt, or an
2257 	 * exception, or we already gave a more specific error.
2258 	 * Also check called_emsg for when using assert_fails().
2259 	 */
2260 	if (!aborting()
2261 		&& did_emsg == did_emsg_before
2262 		&& called_emsg == called_emsg_before
2263 		&& (flags & EVAL_CONSTANT) == 0
2264 		&& (!in_vim9script() || !vim9_bad_comment(p)))
2265 	    semsg(_(e_invexpr2), arg);
2266 
2267 	// Some of the expression may not have been consumed.  Do not check for
2268 	// a next command to avoid more errors, unless "|" is following, which
2269 	// could only be a command separator.
2270 	if (eap != NULL && skipwhite(p)[0] == '|' && skipwhite(p)[1] != '|')
2271 	    eap->nextcmd = check_nextcmd(p);
2272 	return FAIL;
2273     }
2274 
2275     if (eap != NULL)
2276 	eap->nextcmd = check_nextcmd(p);
2277 
2278     return ret;
2279 }
2280 
2281 /*
2282  * Handle top level expression:
2283  *	expr2 ? expr1 : expr1
2284  *	expr2 ?? expr1
2285  *
2286  * "arg" must point to the first non-white of the expression.
2287  * "arg" is advanced to just after the recognized expression.
2288  *
2289  * Note: "rettv.v_lock" is not set.
2290  *
2291  * Return OK or FAIL.
2292  */
2293     int
2294 eval1(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2295 {
2296     char_u  *p;
2297     int	    getnext;
2298 
2299     CLEAR_POINTER(rettv);
2300 
2301     /*
2302      * Get the first variable.
2303      */
2304     if (eval2(arg, rettv, evalarg) == FAIL)
2305 	return FAIL;
2306 
2307     p = eval_next_non_blank(*arg, evalarg, &getnext);
2308     if (*p == '?')
2309     {
2310 	int		op_falsy = p[1] == '?';
2311 	int		result;
2312 	typval_T	var2;
2313 	evalarg_T	*evalarg_used = evalarg;
2314 	evalarg_T	local_evalarg;
2315 	int		orig_flags;
2316 	int		evaluate;
2317 	int		vim9script = in_vim9script();
2318 
2319 	if (evalarg == NULL)
2320 	{
2321 	    CLEAR_FIELD(local_evalarg);
2322 	    evalarg_used = &local_evalarg;
2323 	}
2324 	orig_flags = evalarg_used->eval_flags;
2325 	evaluate = evalarg_used->eval_flags & EVAL_EVALUATE;
2326 
2327 	if (getnext)
2328 	    *arg = eval_next_line(evalarg_used);
2329 	else
2330 	{
2331 	    if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
2332 	    {
2333 		error_white_both(p, 1);
2334 		clear_tv(rettv);
2335 		return FAIL;
2336 	    }
2337 	    *arg = p;
2338 	}
2339 
2340 	result = FALSE;
2341 	if (evaluate)
2342 	{
2343 	    int		error = FALSE;
2344 
2345 	    if (op_falsy)
2346 		result = tv2bool(rettv);
2347 	    else if (vim9script)
2348 		result = tv_get_bool_chk(rettv, &error);
2349 	    else if (tv_get_number_chk(rettv, &error) != 0)
2350 		result = TRUE;
2351 	    if (error || !op_falsy || !result)
2352 		clear_tv(rettv);
2353 	    if (error)
2354 		return FAIL;
2355 	}
2356 
2357 	/*
2358 	 * Get the second variable.  Recursive!
2359 	 */
2360 	if (op_falsy)
2361 	    ++*arg;
2362 	if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[1]))
2363 	{
2364 	    error_white_both(p, 1);
2365 	    clear_tv(rettv);
2366 	    return FAIL;
2367 	}
2368 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg_used);
2369 	evalarg_used->eval_flags = (op_falsy ? !result : result)
2370 				    ? orig_flags : orig_flags & ~EVAL_EVALUATE;
2371 	if (eval1(arg, &var2, evalarg_used) == FAIL)
2372 	{
2373 	    evalarg_used->eval_flags = orig_flags;
2374 	    return FAIL;
2375 	}
2376 	if (!op_falsy || !result)
2377 	    *rettv = var2;
2378 
2379 	if (!op_falsy)
2380 	{
2381 	    /*
2382 	     * Check for the ":".
2383 	     */
2384 	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
2385 	    if (*p != ':')
2386 	    {
2387 		emsg(_(e_missing_colon));
2388 		if (evaluate && result)
2389 		    clear_tv(rettv);
2390 		evalarg_used->eval_flags = orig_flags;
2391 		return FAIL;
2392 	    }
2393 	    if (getnext)
2394 		*arg = eval_next_line(evalarg_used);
2395 	    else
2396 	    {
2397 		if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
2398 		{
2399 		    error_white_both(p, 1);
2400 		    clear_tv(rettv);
2401 		    evalarg_used->eval_flags = orig_flags;
2402 		    return FAIL;
2403 		}
2404 		*arg = p;
2405 	    }
2406 
2407 	    /*
2408 	     * Get the third variable.  Recursive!
2409 	     */
2410 	    if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[1]))
2411 	    {
2412 		error_white_both(p, 1);
2413 		clear_tv(rettv);
2414 		evalarg_used->eval_flags = orig_flags;
2415 		return FAIL;
2416 	    }
2417 	    *arg = skipwhite_and_linebreak(*arg + 1, evalarg_used);
2418 	    evalarg_used->eval_flags = !result ? orig_flags
2419 						 : orig_flags & ~EVAL_EVALUATE;
2420 	    if (eval1(arg, &var2, evalarg_used) == FAIL)
2421 	    {
2422 		if (evaluate && result)
2423 		    clear_tv(rettv);
2424 		evalarg_used->eval_flags = orig_flags;
2425 		return FAIL;
2426 	    }
2427 	    if (evaluate && !result)
2428 		*rettv = var2;
2429 	}
2430 
2431 	if (evalarg == NULL)
2432 	    clear_evalarg(&local_evalarg, NULL);
2433 	else
2434 	    evalarg->eval_flags = orig_flags;
2435     }
2436 
2437     return OK;
2438 }
2439 
2440 /*
2441  * Handle first level expression:
2442  *	expr2 || expr2 || expr2	    logical OR
2443  *
2444  * "arg" must point to the first non-white of the expression.
2445  * "arg" is advanced to just after the recognized expression.
2446  *
2447  * Return OK or FAIL.
2448  */
2449     static int
2450 eval2(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2451 {
2452     char_u	*p;
2453     int		getnext;
2454 
2455     /*
2456      * Get the first variable.
2457      */
2458     if (eval3(arg, rettv, evalarg) == FAIL)
2459 	return FAIL;
2460 
2461     /*
2462      * Handle the  "||" operator.
2463      */
2464     p = eval_next_non_blank(*arg, evalarg, &getnext);
2465     if (p[0] == '|' && p[1] == '|')
2466     {
2467 	evalarg_T   *evalarg_used = evalarg;
2468 	evalarg_T   local_evalarg;
2469 	int	    evaluate;
2470 	int	    orig_flags;
2471 	long	    result = FALSE;
2472 	typval_T    var2;
2473 	int	    error = FALSE;
2474 	int	    vim9script = in_vim9script();
2475 
2476 	if (evalarg == NULL)
2477 	{
2478 	    CLEAR_FIELD(local_evalarg);
2479 	    evalarg_used = &local_evalarg;
2480 	}
2481 	orig_flags = evalarg_used->eval_flags;
2482 	evaluate = orig_flags & EVAL_EVALUATE;
2483 	if (evaluate)
2484 	{
2485 	    if (vim9script)
2486 		result = tv_get_bool_chk(rettv, &error);
2487 	    else if (tv_get_number_chk(rettv, &error) != 0)
2488 		result = TRUE;
2489 	    clear_tv(rettv);
2490 	    if (error)
2491 		return FAIL;
2492 	}
2493 
2494 	/*
2495 	 * Repeat until there is no following "||".
2496 	 */
2497 	while (p[0] == '|' && p[1] == '|')
2498 	{
2499 	    if (getnext)
2500 		*arg = eval_next_line(evalarg_used);
2501 	    else
2502 	    {
2503 		if (evaluate && in_vim9script() && !VIM_ISWHITE(p[-1]))
2504 		{
2505 		    error_white_both(p, 2);
2506 		    clear_tv(rettv);
2507 		    return FAIL;
2508 		}
2509 		*arg = p;
2510 	    }
2511 
2512 	    /*
2513 	     * Get the second variable.
2514 	     */
2515 	    if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[2]))
2516 	    {
2517 		error_white_both(p, 2);
2518 		clear_tv(rettv);
2519 		return FAIL;
2520 	    }
2521 	    *arg = skipwhite_and_linebreak(*arg + 2, evalarg_used);
2522 	    evalarg_used->eval_flags = !result ? orig_flags
2523 						 : orig_flags & ~EVAL_EVALUATE;
2524 	    if (eval3(arg, &var2, evalarg_used) == FAIL)
2525 		return FAIL;
2526 
2527 	    /*
2528 	     * Compute the result.
2529 	     */
2530 	    if (evaluate && !result)
2531 	    {
2532 		if (vim9script)
2533 		    result = tv_get_bool_chk(&var2, &error);
2534 		else if (tv_get_number_chk(&var2, &error) != 0)
2535 		    result = TRUE;
2536 		clear_tv(&var2);
2537 		if (error)
2538 		    return FAIL;
2539 	    }
2540 	    if (evaluate)
2541 	    {
2542 		if (vim9script)
2543 		{
2544 		    rettv->v_type = VAR_BOOL;
2545 		    rettv->vval.v_number = result ? VVAL_TRUE : VVAL_FALSE;
2546 		}
2547 		else
2548 		{
2549 		    rettv->v_type = VAR_NUMBER;
2550 		    rettv->vval.v_number = result;
2551 		}
2552 	    }
2553 
2554 	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
2555 	}
2556 
2557 	if (evalarg == NULL)
2558 	    clear_evalarg(&local_evalarg, NULL);
2559 	else
2560 	    evalarg->eval_flags = orig_flags;
2561     }
2562 
2563     return OK;
2564 }
2565 
2566 /*
2567  * Handle second level expression:
2568  *	expr3 && expr3 && expr3	    logical AND
2569  *
2570  * "arg" must point to the first non-white of the expression.
2571  * "arg" is advanced to just after the recognized expression.
2572  *
2573  * Return OK or FAIL.
2574  */
2575     static int
2576 eval3(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2577 {
2578     char_u	*p;
2579     int		getnext;
2580 
2581     /*
2582      * Get the first variable.
2583      */
2584     if (eval4(arg, rettv, evalarg) == FAIL)
2585 	return FAIL;
2586 
2587     /*
2588      * Handle the "&&" operator.
2589      */
2590     p = eval_next_non_blank(*arg, evalarg, &getnext);
2591     if (p[0] == '&' && p[1] == '&')
2592     {
2593 	evalarg_T   *evalarg_used = evalarg;
2594 	evalarg_T   local_evalarg;
2595 	int	    orig_flags;
2596 	int	    evaluate;
2597 	long	    result = TRUE;
2598 	typval_T    var2;
2599 	int	    error = FALSE;
2600 	int	    vim9script = in_vim9script();
2601 
2602 	if (evalarg == NULL)
2603 	{
2604 	    CLEAR_FIELD(local_evalarg);
2605 	    evalarg_used = &local_evalarg;
2606 	}
2607 	orig_flags = evalarg_used->eval_flags;
2608 	evaluate = orig_flags & EVAL_EVALUATE;
2609 	if (evaluate)
2610 	{
2611 	    if (vim9script)
2612 		result = tv_get_bool_chk(rettv, &error);
2613 	    else if (tv_get_number_chk(rettv, &error) == 0)
2614 		result = FALSE;
2615 	    clear_tv(rettv);
2616 	    if (error)
2617 		return FAIL;
2618 	}
2619 
2620 	/*
2621 	 * Repeat until there is no following "&&".
2622 	 */
2623 	while (p[0] == '&' && p[1] == '&')
2624 	{
2625 	    if (getnext)
2626 		*arg = eval_next_line(evalarg_used);
2627 	    else
2628 	    {
2629 		if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
2630 		{
2631 		    error_white_both(p, 2);
2632 		    clear_tv(rettv);
2633 		    return FAIL;
2634 		}
2635 		*arg = p;
2636 	    }
2637 
2638 	    /*
2639 	     * Get the second variable.
2640 	     */
2641 	    if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[2]))
2642 	    {
2643 		error_white_both(p, 2);
2644 		clear_tv(rettv);
2645 		return FAIL;
2646 	    }
2647 	    *arg = skipwhite_and_linebreak(*arg + 2, evalarg_used);
2648 	    evalarg_used->eval_flags = result ? orig_flags
2649 						 : orig_flags & ~EVAL_EVALUATE;
2650 	    CLEAR_FIELD(var2);
2651 	    if (eval4(arg, &var2, evalarg_used) == FAIL)
2652 		return FAIL;
2653 
2654 	    /*
2655 	     * Compute the result.
2656 	     */
2657 	    if (evaluate && result)
2658 	    {
2659 		if (vim9script)
2660 		    result = tv_get_bool_chk(&var2, &error);
2661 		else if (tv_get_number_chk(&var2, &error) == 0)
2662 		    result = FALSE;
2663 		clear_tv(&var2);
2664 		if (error)
2665 		    return FAIL;
2666 	    }
2667 	    if (evaluate)
2668 	    {
2669 		if (vim9script)
2670 		{
2671 		    rettv->v_type = VAR_BOOL;
2672 		    rettv->vval.v_number = result ? VVAL_TRUE : VVAL_FALSE;
2673 		}
2674 		else
2675 		{
2676 		    rettv->v_type = VAR_NUMBER;
2677 		    rettv->vval.v_number = result;
2678 		}
2679 	    }
2680 
2681 	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
2682 	}
2683 
2684 	if (evalarg == NULL)
2685 	    clear_evalarg(&local_evalarg, NULL);
2686 	else
2687 	    evalarg->eval_flags = orig_flags;
2688     }
2689 
2690     return OK;
2691 }
2692 
2693 /*
2694  * Handle third level expression:
2695  *	var1 == var2
2696  *	var1 =~ var2
2697  *	var1 != var2
2698  *	var1 !~ var2
2699  *	var1 > var2
2700  *	var1 >= var2
2701  *	var1 < var2
2702  *	var1 <= var2
2703  *	var1 is var2
2704  *	var1 isnot var2
2705  *
2706  * "arg" must point to the first non-white of the expression.
2707  * "arg" is advanced to just after the recognized expression.
2708  *
2709  * Return OK or FAIL.
2710  */
2711     static int
2712 eval4(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2713 {
2714     char_u	*p;
2715     int		getnext;
2716     exprtype_T	type = EXPR_UNKNOWN;
2717     int		len = 2;
2718     int		type_is = FALSE;
2719 
2720     /*
2721      * Get the first variable.
2722      */
2723     if (eval5(arg, rettv, evalarg) == FAIL)
2724 	return FAIL;
2725 
2726     p = eval_next_non_blank(*arg, evalarg, &getnext);
2727     type = get_compare_type(p, &len, &type_is);
2728 
2729     /*
2730      * If there is a comparative operator, use it.
2731      */
2732     if (type != EXPR_UNKNOWN)
2733     {
2734 	typval_T    var2;
2735 	int	    ic;
2736 	int	    vim9script = in_vim9script();
2737 	int	    evaluate = evalarg == NULL
2738 				   ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
2739 
2740 	if (getnext)
2741 	    *arg = eval_next_line(evalarg);
2742 	else if (evaluate && vim9script && !VIM_ISWHITE(**arg))
2743 	{
2744 	    error_white_both(p, len);
2745 	    clear_tv(rettv);
2746 	    return FAIL;
2747 	}
2748 
2749 	if (vim9script && type_is && (p[len] == '?' || p[len] == '#'))
2750 	{
2751 	    semsg(_(e_invexpr2), p);
2752 	    clear_tv(rettv);
2753 	    return FAIL;
2754 	}
2755 
2756 	// extra question mark appended: ignore case
2757 	if (p[len] == '?')
2758 	{
2759 	    ic = TRUE;
2760 	    ++len;
2761 	}
2762 	// extra '#' appended: match case
2763 	else if (p[len] == '#')
2764 	{
2765 	    ic = FALSE;
2766 	    ++len;
2767 	}
2768 	// nothing appended: use 'ignorecase' if not in Vim script
2769 	else
2770 	    ic = vim9script ? FALSE : p_ic;
2771 
2772 	/*
2773 	 * Get the second variable.
2774 	 */
2775 	if (evaluate && vim9script && !IS_WHITE_OR_NUL(p[len]))
2776 	{
2777 	    error_white_both(p, 1);
2778 	    clear_tv(rettv);
2779 	    return FAIL;
2780 	}
2781 	*arg = skipwhite_and_linebreak(p + len, evalarg);
2782 	if (eval5(arg, &var2, evalarg) == FAIL)
2783 	{
2784 	    clear_tv(rettv);
2785 	    return FAIL;
2786 	}
2787 	if (evaluate)
2788 	{
2789 	    int ret;
2790 
2791 	    if (vim9script && check_compare_types(type, rettv, &var2) == FAIL)
2792 	    {
2793 		ret = FAIL;
2794 		clear_tv(rettv);
2795 	    }
2796 	    else
2797 		ret = typval_compare(rettv, &var2, type, ic);
2798 	    clear_tv(&var2);
2799 	    return ret;
2800 	}
2801     }
2802 
2803     return OK;
2804 }
2805 
2806 /*
2807  * Make a copy of blob "tv1" and append blob "tv2".
2808  */
2809     void
2810 eval_addblob(typval_T *tv1, typval_T *tv2)
2811 {
2812     blob_T  *b1 = tv1->vval.v_blob;
2813     blob_T  *b2 = tv2->vval.v_blob;
2814     blob_T  *b = blob_alloc();
2815     int	    i;
2816 
2817     if (b != NULL)
2818     {
2819 	for (i = 0; i < blob_len(b1); i++)
2820 	    ga_append(&b->bv_ga, blob_get(b1, i));
2821 	for (i = 0; i < blob_len(b2); i++)
2822 	    ga_append(&b->bv_ga, blob_get(b2, i));
2823 
2824 	clear_tv(tv1);
2825 	rettv_blob_set(tv1, b);
2826     }
2827 }
2828 
2829 /*
2830  * Make a copy of list "tv1" and append list "tv2".
2831  */
2832     int
2833 eval_addlist(typval_T *tv1, typval_T *tv2)
2834 {
2835     typval_T var3;
2836 
2837     // concatenate Lists
2838     if (list_concat(tv1->vval.v_list, tv2->vval.v_list, &var3) == FAIL)
2839     {
2840 	clear_tv(tv1);
2841 	clear_tv(tv2);
2842 	return FAIL;
2843     }
2844     clear_tv(tv1);
2845     *tv1 = var3;
2846     return OK;
2847 }
2848 
2849 /*
2850  * Handle fourth level expression:
2851  *	+	number addition
2852  *	-	number subtraction
2853  *	.	string concatenation (if script version is 1)
2854  *	..	string concatenation
2855  *
2856  * "arg" must point to the first non-white of the expression.
2857  * "arg" is advanced to just after the recognized expression.
2858  *
2859  * Return OK or FAIL.
2860  */
2861     static int
2862 eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2863 {
2864     /*
2865      * Get the first variable.
2866      */
2867     if (eval6(arg, rettv, evalarg, FALSE) == FAIL)
2868 	return FAIL;
2869 
2870     /*
2871      * Repeat computing, until no '+', '-' or '.' is following.
2872      */
2873     for (;;)
2874     {
2875 	int	    evaluate;
2876 	int	    getnext;
2877 	char_u	    *p;
2878 	int	    op;
2879 	int	    oplen;
2880 	int	    concat;
2881 	typval_T    var2;
2882 	int	    vim9script = in_vim9script();
2883 
2884 	// "." is only string concatenation when scriptversion is 1
2885 	// "+=", "-=" and "..=" are assignments
2886 	p = eval_next_non_blank(*arg, evalarg, &getnext);
2887 	op = *p;
2888 	concat = op == '.' && (*(p + 1) == '.' || current_sctx.sc_version < 2);
2889 	if ((op != '+' && op != '-' && !concat) || p[1] == '='
2890 					       || (p[1] == '.' && p[2] == '='))
2891 	    break;
2892 
2893 	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
2894 	oplen = (concat && p[1] == '.') ? 2 : 1;
2895 	if (getnext)
2896 	    *arg = eval_next_line(evalarg);
2897 	else
2898 	{
2899 	    if (evaluate && vim9script && !VIM_ISWHITE(**arg))
2900 	    {
2901 		error_white_both(p, oplen);
2902 		clear_tv(rettv);
2903 		return FAIL;
2904 	    }
2905 	    *arg = p;
2906 	}
2907 	if ((op != '+' || (rettv->v_type != VAR_LIST
2908 						 && rettv->v_type != VAR_BLOB))
2909 #ifdef FEAT_FLOAT
2910 		&& (op == '.' || rettv->v_type != VAR_FLOAT)
2911 #endif
2912 		&& evaluate)
2913 	{
2914 	    int		error = FALSE;
2915 
2916 	    // For "list + ...", an illegal use of the first operand as
2917 	    // a number cannot be determined before evaluating the 2nd
2918 	    // operand: if this is also a list, all is ok.
2919 	    // For "something . ...", "something - ..." or "non-list + ...",
2920 	    // we know that the first operand needs to be a string or number
2921 	    // without evaluating the 2nd operand.  So check before to avoid
2922 	    // side effects after an error.
2923 	    if (op != '.')
2924 		tv_get_number_chk(rettv, &error);
2925 	    if ((op == '.' && tv_get_string_chk(rettv) == NULL) || error)
2926 	    {
2927 		clear_tv(rettv);
2928 		return FAIL;
2929 	    }
2930 	}
2931 
2932 	/*
2933 	 * Get the second variable.
2934 	 */
2935 	if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[oplen]))
2936 	{
2937 	    error_white_both(p, oplen);
2938 	    clear_tv(rettv);
2939 	    return FAIL;
2940 	}
2941 	*arg = skipwhite_and_linebreak(*arg + oplen, evalarg);
2942 	if (eval6(arg, &var2, evalarg, !vim9script && op == '.') == FAIL)
2943 	{
2944 	    clear_tv(rettv);
2945 	    return FAIL;
2946 	}
2947 
2948 	if (evaluate)
2949 	{
2950 	    /*
2951 	     * Compute the result.
2952 	     */
2953 	    if (op == '.')
2954 	    {
2955 		char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
2956 		char_u	*s1 = tv_get_string_buf(rettv, buf1);
2957 		char_u	*s2 = NULL;
2958 
2959 		if (vim9script && (var2.v_type == VAR_VOID
2960 			|| var2.v_type == VAR_CHANNEL
2961 			|| var2.v_type == VAR_JOB))
2962 		    emsg(_(e_inval_string));
2963 #ifdef FEAT_FLOAT
2964 		else if (vim9script && var2.v_type == VAR_FLOAT)
2965 		{
2966 		    vim_snprintf((char *)buf2, NUMBUFLEN, "%g",
2967 							    var2.vval.v_float);
2968 		    s2 = buf2;
2969 		}
2970 #endif
2971 		else
2972 		    s2 = tv_get_string_buf_chk(&var2, buf2);
2973 		if (s2 == NULL)		// type error ?
2974 		{
2975 		    clear_tv(rettv);
2976 		    clear_tv(&var2);
2977 		    return FAIL;
2978 		}
2979 		p = concat_str(s1, s2);
2980 		clear_tv(rettv);
2981 		rettv->v_type = VAR_STRING;
2982 		rettv->vval.v_string = p;
2983 	    }
2984 	    else if (op == '+' && rettv->v_type == VAR_BLOB
2985 						   && var2.v_type == VAR_BLOB)
2986 		eval_addblob(rettv, &var2);
2987 	    else if (op == '+' && rettv->v_type == VAR_LIST
2988 						   && var2.v_type == VAR_LIST)
2989 	    {
2990 		if (eval_addlist(rettv, &var2) == FAIL)
2991 		    return FAIL;
2992 	    }
2993 	    else
2994 	    {
2995 		int		error = FALSE;
2996 		varnumber_T	n1, n2;
2997 #ifdef FEAT_FLOAT
2998 		float_T	    f1 = 0, f2 = 0;
2999 
3000 		if (rettv->v_type == VAR_FLOAT)
3001 		{
3002 		    f1 = rettv->vval.v_float;
3003 		    n1 = 0;
3004 		}
3005 		else
3006 #endif
3007 		{
3008 		    n1 = tv_get_number_chk(rettv, &error);
3009 		    if (error)
3010 		    {
3011 			// This can only happen for "list + non-list".  For
3012 			// "non-list + ..." or "something - ...", we returned
3013 			// before evaluating the 2nd operand.
3014 			clear_tv(rettv);
3015 			return FAIL;
3016 		    }
3017 #ifdef FEAT_FLOAT
3018 		    if (var2.v_type == VAR_FLOAT)
3019 			f1 = n1;
3020 #endif
3021 		}
3022 #ifdef FEAT_FLOAT
3023 		if (var2.v_type == VAR_FLOAT)
3024 		{
3025 		    f2 = var2.vval.v_float;
3026 		    n2 = 0;
3027 		}
3028 		else
3029 #endif
3030 		{
3031 		    n2 = tv_get_number_chk(&var2, &error);
3032 		    if (error)
3033 		    {
3034 			clear_tv(rettv);
3035 			clear_tv(&var2);
3036 			return FAIL;
3037 		    }
3038 #ifdef FEAT_FLOAT
3039 		    if (rettv->v_type == VAR_FLOAT)
3040 			f2 = n2;
3041 #endif
3042 		}
3043 		clear_tv(rettv);
3044 
3045 #ifdef FEAT_FLOAT
3046 		// If there is a float on either side the result is a float.
3047 		if (rettv->v_type == VAR_FLOAT || var2.v_type == VAR_FLOAT)
3048 		{
3049 		    if (op == '+')
3050 			f1 = f1 + f2;
3051 		    else
3052 			f1 = f1 - f2;
3053 		    rettv->v_type = VAR_FLOAT;
3054 		    rettv->vval.v_float = f1;
3055 		}
3056 		else
3057 #endif
3058 		{
3059 		    if (op == '+')
3060 			n1 = n1 + n2;
3061 		    else
3062 			n1 = n1 - n2;
3063 		    rettv->v_type = VAR_NUMBER;
3064 		    rettv->vval.v_number = n1;
3065 		}
3066 	    }
3067 	    clear_tv(&var2);
3068 	}
3069     }
3070     return OK;
3071 }
3072 
3073 /*
3074  * Handle fifth level expression:
3075  *	*	number multiplication
3076  *	/	number division
3077  *	%	number modulo
3078  *
3079  * "arg" must point to the first non-white of the expression.
3080  * "arg" is advanced to just after the recognized expression.
3081  *
3082  * Return OK or FAIL.
3083  */
3084     static int
3085 eval6(
3086     char_u	**arg,
3087     typval_T	*rettv,
3088     evalarg_T	*evalarg,
3089     int		want_string)  // after "." operator
3090 {
3091 #ifdef FEAT_FLOAT
3092     int	    use_float = FALSE;
3093 #endif
3094 
3095     /*
3096      * Get the first variable.
3097      */
3098     if (eval7(arg, rettv, evalarg, want_string) == FAIL)
3099 	return FAIL;
3100 
3101     /*
3102      * Repeat computing, until no '*', '/' or '%' is following.
3103      */
3104     for (;;)
3105     {
3106 	int	    evaluate;
3107 	int	    getnext;
3108 	typval_T    var2;
3109 	char_u	    *p;
3110 	int	    op;
3111 	varnumber_T n1, n2;
3112 #ifdef FEAT_FLOAT
3113 	float_T	    f1, f2;
3114 #endif
3115 	int	    error;
3116 
3117 	// "*=", "/=" and "%=" are assignments
3118 	p = eval_next_non_blank(*arg, evalarg, &getnext);
3119 	op = *p;
3120 	if ((op != '*' && op != '/' && op != '%') || p[1] == '=')
3121 	    break;
3122 
3123 	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
3124 	if (getnext)
3125 	    *arg = eval_next_line(evalarg);
3126 	else
3127 	{
3128 	    if (evaluate && in_vim9script() && !VIM_ISWHITE(**arg))
3129 	    {
3130 		error_white_both(p, 1);
3131 		clear_tv(rettv);
3132 		return FAIL;
3133 	    }
3134 	    *arg = p;
3135 	}
3136 
3137 #ifdef FEAT_FLOAT
3138 	f1 = 0;
3139 	f2 = 0;
3140 #endif
3141 	error = FALSE;
3142 	if (evaluate)
3143 	{
3144 #ifdef FEAT_FLOAT
3145 	    if (rettv->v_type == VAR_FLOAT)
3146 	    {
3147 		f1 = rettv->vval.v_float;
3148 		use_float = TRUE;
3149 		n1 = 0;
3150 	    }
3151 	    else
3152 #endif
3153 		n1 = tv_get_number_chk(rettv, &error);
3154 	    clear_tv(rettv);
3155 	    if (error)
3156 		return FAIL;
3157 	}
3158 	else
3159 	    n1 = 0;
3160 
3161 	/*
3162 	 * Get the second variable.
3163 	 */
3164 	if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[1]))
3165 	{
3166 	    error_white_both(*arg, 1);
3167 	    clear_tv(rettv);
3168 	    return FAIL;
3169 	}
3170 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3171 	if (eval7(arg, &var2, evalarg, FALSE) == FAIL)
3172 	    return FAIL;
3173 
3174 	if (evaluate)
3175 	{
3176 #ifdef FEAT_FLOAT
3177 	    if (var2.v_type == VAR_FLOAT)
3178 	    {
3179 		if (!use_float)
3180 		{
3181 		    f1 = n1;
3182 		    use_float = TRUE;
3183 		}
3184 		f2 = var2.vval.v_float;
3185 		n2 = 0;
3186 	    }
3187 	    else
3188 #endif
3189 	    {
3190 		n2 = tv_get_number_chk(&var2, &error);
3191 		clear_tv(&var2);
3192 		if (error)
3193 		    return FAIL;
3194 #ifdef FEAT_FLOAT
3195 		if (use_float)
3196 		    f2 = n2;
3197 #endif
3198 	    }
3199 
3200 	    /*
3201 	     * Compute the result.
3202 	     * When either side is a float the result is a float.
3203 	     */
3204 #ifdef FEAT_FLOAT
3205 	    if (use_float)
3206 	    {
3207 		if (op == '*')
3208 		    f1 = f1 * f2;
3209 		else if (op == '/')
3210 		{
3211 # ifdef VMS
3212 		    // VMS crashes on divide by zero, work around it
3213 		    if (f2 == 0.0)
3214 		    {
3215 			if (f1 == 0)
3216 			    f1 = -1 * __F_FLT_MAX - 1L;   // similar to NaN
3217 			else if (f1 < 0)
3218 			    f1 = -1 * __F_FLT_MAX;
3219 			else
3220 			    f1 = __F_FLT_MAX;
3221 		    }
3222 		    else
3223 			f1 = f1 / f2;
3224 # else
3225 		    // We rely on the floating point library to handle divide
3226 		    // by zero to result in "inf" and not a crash.
3227 		    f1 = f1 / f2;
3228 # endif
3229 		}
3230 		else
3231 		{
3232 		    emsg(_(e_modulus));
3233 		    return FAIL;
3234 		}
3235 		rettv->v_type = VAR_FLOAT;
3236 		rettv->vval.v_float = f1;
3237 	    }
3238 	    else
3239 #endif
3240 	    {
3241 		int	    failed = FALSE;
3242 
3243 		if (op == '*')
3244 		    n1 = n1 * n2;
3245 		else if (op == '/')
3246 		    n1 = num_divide(n1, n2, &failed);
3247 		else
3248 		    n1 = num_modulus(n1, n2, &failed);
3249 		if (failed)
3250 		    return FAIL;
3251 
3252 		rettv->v_type = VAR_NUMBER;
3253 		rettv->vval.v_number = n1;
3254 	    }
3255 	}
3256     }
3257 
3258     return OK;
3259 }
3260 
3261     int
3262 eval_leader(char_u **arg, int vim9)
3263 {
3264     char_u	*s = *arg;
3265     char_u	*p = *arg;
3266 
3267     while (*p == '!' || *p == '-' || *p == '+')
3268     {
3269 	char_u *n = skipwhite(p + 1);
3270 
3271 	// ++, --, -+ and +- are not accepted in Vim9 script
3272 	if (vim9 && (*p == '-' || *p == '+') && (*n == '-' || *n == '+'))
3273 	{
3274 	    semsg(_(e_invexpr2), s);
3275 	    return FAIL;
3276 	}
3277 	p = n;
3278     }
3279     *arg = p;
3280     return OK;
3281 }
3282 
3283 /*
3284  * Handle sixth level expression:
3285  *  number		number constant
3286  *  0zFFFFFFFF		Blob constant
3287  *  "string"		string constant
3288  *  'string'		literal string constant
3289  *  &option-name	option value
3290  *  @r			register contents
3291  *  identifier		variable value
3292  *  function()		function call
3293  *  $VAR		environment variable
3294  *  (expression)	nested expression
3295  *  [expr, expr]	List
3296  *  {arg, arg -> expr}	Lambda
3297  *  {key: val, key: val}   Dictionary
3298  *  #{key: val, key: val}  Dictionary with literal keys
3299  *
3300  *  Also handle:
3301  *  ! in front		logical NOT
3302  *  - in front		unary minus
3303  *  + in front		unary plus (ignored)
3304  *  trailing []		subscript in String or List
3305  *  trailing .name	entry in Dictionary
3306  *  trailing ->name()	method call
3307  *
3308  * "arg" must point to the first non-white of the expression.
3309  * "arg" is advanced to just after the recognized expression.
3310  *
3311  * Return OK or FAIL.
3312  */
3313     static int
3314 eval7(
3315     char_u	**arg,
3316     typval_T	*rettv,
3317     evalarg_T	*evalarg,
3318     int		want_string)	// after "." operator
3319 {
3320     int		evaluate = evalarg != NULL
3321 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3322     int		len;
3323     char_u	*s;
3324     char_u	*start_leader, *end_leader;
3325     int		ret = OK;
3326     char_u	*alias;
3327 
3328     /*
3329      * Initialise variable so that clear_tv() can't mistake this for a
3330      * string and free a string that isn't there.
3331      */
3332     rettv->v_type = VAR_UNKNOWN;
3333 
3334     /*
3335      * Skip '!', '-' and '+' characters.  They are handled later.
3336      */
3337     start_leader = *arg;
3338     if (eval_leader(arg, in_vim9script()) == FAIL)
3339 	return FAIL;
3340     end_leader = *arg;
3341 
3342     if (**arg == '.' && (!isdigit(*(*arg + 1))
3343 #ifdef FEAT_FLOAT
3344 	    || current_sctx.sc_version < 2
3345 #endif
3346 	    ))
3347     {
3348 	semsg(_(e_invexpr2), *arg);
3349 	++*arg;
3350 	return FAIL;
3351     }
3352 
3353     switch (**arg)
3354     {
3355     /*
3356      * Number constant.
3357      */
3358     case '0':
3359     case '1':
3360     case '2':
3361     case '3':
3362     case '4':
3363     case '5':
3364     case '6':
3365     case '7':
3366     case '8':
3367     case '9':
3368     case '.':	ret = eval_number(arg, rettv, evaluate, want_string);
3369 
3370 		// Apply prefixed "-" and "+" now.  Matters especially when
3371 		// "->" follows.
3372 		if (ret == OK && evaluate && end_leader > start_leader
3373 						  && rettv->v_type != VAR_BLOB)
3374 		    ret = eval7_leader(rettv, TRUE, start_leader, &end_leader);
3375 		break;
3376 
3377     /*
3378      * String constant: "string".
3379      */
3380     case '"':	ret = eval_string(arg, rettv, evaluate);
3381 		break;
3382 
3383     /*
3384      * Literal string constant: 'str''ing'.
3385      */
3386     case '\'':	ret = eval_lit_string(arg, rettv, evaluate);
3387 		break;
3388 
3389     /*
3390      * List: [expr, expr]
3391      */
3392     case '[':	ret = eval_list(arg, rettv, evalarg, TRUE);
3393 		break;
3394 
3395     /*
3396      * Dictionary: #{key: val, key: val}
3397      */
3398     case '#':	if (in_vim9script())
3399 		{
3400 		    ret = vim9_bad_comment(*arg) ? FAIL : NOTDONE;
3401 		}
3402 		else if ((*arg)[1] == '{')
3403 		{
3404 		    ++*arg;
3405 		    ret = eval_dict(arg, rettv, evalarg, TRUE);
3406 		}
3407 		else
3408 		    ret = NOTDONE;
3409 		break;
3410 
3411     /*
3412      * Lambda: {arg, arg -> expr}
3413      * Dictionary: {'key': val, 'key': val}
3414      */
3415     case '{':	if (in_vim9script())
3416 		    ret = NOTDONE;
3417 		else
3418 		    ret = get_lambda_tv(arg, rettv, in_vim9script(), evalarg);
3419 		if (ret == NOTDONE)
3420 		    ret = eval_dict(arg, rettv, evalarg, FALSE);
3421 		break;
3422 
3423     /*
3424      * Option value: &name
3425      */
3426     case '&':	ret = eval_option(arg, rettv, evaluate);
3427 		break;
3428 
3429     /*
3430      * Environment variable: $VAR.
3431      */
3432     case '$':	ret = eval_env_var(arg, rettv, evaluate);
3433 		break;
3434 
3435     /*
3436      * Register contents: @r.
3437      */
3438     case '@':	++*arg;
3439 		if (evaluate)
3440 		{
3441 		    rettv->v_type = VAR_STRING;
3442 		    rettv->vval.v_string = get_reg_contents(**arg,
3443 							    GREG_EXPR_SRC);
3444 		}
3445 		if (**arg != NUL)
3446 		    ++*arg;
3447 		break;
3448 
3449     /*
3450      * nested expression: (expression).
3451      * lambda: (arg) => expr
3452      */
3453     case '(':	ret = NOTDONE;
3454 		if (in_vim9script())
3455 		{
3456 		    ret = get_lambda_tv(arg, rettv, TRUE, evalarg);
3457 		    if (ret == OK && evaluate)
3458 		    {
3459 			ufunc_T *ufunc = rettv->vval.v_partial->pt_func;
3460 
3461 			// compile it here to get the return type
3462 			if (compile_def_function(ufunc,
3463 					 TRUE, PROFILING(ufunc), NULL) == FAIL)
3464 			{
3465 			    clear_tv(rettv);
3466 			    ret = FAIL;
3467 			}
3468 		    }
3469 		}
3470 		if (ret == NOTDONE)
3471 		{
3472 		    *arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3473 		    ret = eval1(arg, rettv, evalarg);	// recursive!
3474 
3475 		    *arg = skipwhite_and_linebreak(*arg, evalarg);
3476 		    if (**arg == ')')
3477 			++*arg;
3478 		    else if (ret == OK)
3479 		    {
3480 			emsg(_(e_missing_close));
3481 			clear_tv(rettv);
3482 			ret = FAIL;
3483 		    }
3484 		}
3485 		break;
3486 
3487     default:	ret = NOTDONE;
3488 		break;
3489     }
3490 
3491     if (ret == NOTDONE)
3492     {
3493 	/*
3494 	 * Must be a variable or function name.
3495 	 * Can also be a curly-braces kind of name: {expr}.
3496 	 */
3497 	s = *arg;
3498 	len = get_name_len(arg, &alias, evaluate, TRUE);
3499 	if (alias != NULL)
3500 	    s = alias;
3501 
3502 	if (len <= 0)
3503 	    ret = FAIL;
3504 	else
3505 	{
3506 	    int	    flags = evalarg == NULL ? 0 : evalarg->eval_flags;
3507 
3508 	    if ((in_vim9script() ? **arg : *skipwhite(*arg)) == '(')
3509 	    {
3510 		// "name(..."  recursive!
3511 		*arg = skipwhite(*arg);
3512 		ret = eval_func(arg, evalarg, s, len, rettv, flags, NULL);
3513 	    }
3514 	    else if (flags & EVAL_CONSTANT)
3515 		ret = FAIL;
3516 	    else if (evaluate)
3517 	    {
3518 		// get the value of "true", "false" or a variable
3519 		if (len == 4 && in_vim9script() && STRNCMP(s, "true", 4) == 0)
3520 		{
3521 		    rettv->v_type = VAR_BOOL;
3522 		    rettv->vval.v_number = VVAL_TRUE;
3523 		    ret = OK;
3524 		}
3525 		else if (len == 5 && in_vim9script()
3526 						&& STRNCMP(s, "false", 5) == 0)
3527 		{
3528 		    rettv->v_type = VAR_BOOL;
3529 		    rettv->vval.v_number = VVAL_FALSE;
3530 		    ret = OK;
3531 		}
3532 		else if (len == 4 && in_vim9script()
3533 						&& STRNCMP(s, "null", 4) == 0)
3534 		{
3535 		    rettv->v_type = VAR_SPECIAL;
3536 		    rettv->vval.v_number = VVAL_NULL;
3537 		    ret = OK;
3538 		}
3539 		else
3540 		    ret = eval_variable(s, len, rettv, NULL,
3541 					   EVAL_VAR_VERBOSE + EVAL_VAR_IMPORT);
3542 	    }
3543 	    else
3544 	    {
3545 		// skip the name
3546 		check_vars(s, len);
3547 		ret = OK;
3548 	    }
3549 	}
3550 	vim_free(alias);
3551     }
3552 
3553     // Handle following '[', '(' and '.' for expr[expr], expr.name,
3554     // expr(expr), expr->name(expr)
3555     if (ret == OK)
3556 	ret = handle_subscript(arg, rettv, evalarg, TRUE);
3557 
3558     /*
3559      * Apply logical NOT and unary '-', from right to left, ignore '+'.
3560      */
3561     if (ret == OK && evaluate && end_leader > start_leader)
3562 	ret = eval7_leader(rettv, FALSE, start_leader, &end_leader);
3563     return ret;
3564 }
3565 
3566 /*
3567  * Apply the leading "!" and "-" before an eval7 expression to "rettv".
3568  * When "numeric_only" is TRUE only handle "+" and "-".
3569  * Adjusts "end_leaderp" until it is at "start_leader".
3570  */
3571     static int
3572 eval7_leader(
3573 	typval_T    *rettv,
3574 	int	    numeric_only,
3575 	char_u	    *start_leader,
3576 	char_u	    **end_leaderp)
3577 {
3578     char_u	*end_leader = *end_leaderp;
3579     int		ret = OK;
3580     int		error = FALSE;
3581     varnumber_T val = 0;
3582     vartype_T	type = rettv->v_type;
3583 #ifdef FEAT_FLOAT
3584     float_T	    f = 0.0;
3585 
3586     if (rettv->v_type == VAR_FLOAT)
3587 	f = rettv->vval.v_float;
3588     else
3589 #endif
3590     {
3591 	while (VIM_ISWHITE(end_leader[-1]))
3592 	    --end_leader;
3593 	if (in_vim9script() && end_leader[-1] == '!')
3594 	    val = tv2bool(rettv);
3595 	else
3596 	    val = tv_get_number_chk(rettv, &error);
3597     }
3598     if (error)
3599     {
3600 	clear_tv(rettv);
3601 	ret = FAIL;
3602     }
3603     else
3604     {
3605 	while (end_leader > start_leader)
3606 	{
3607 	    --end_leader;
3608 	    if (*end_leader == '!')
3609 	    {
3610 		if (numeric_only)
3611 		{
3612 		    ++end_leader;
3613 		    break;
3614 		}
3615 #ifdef FEAT_FLOAT
3616 		if (rettv->v_type == VAR_FLOAT)
3617 		{
3618 		    if (in_vim9script())
3619 		    {
3620 			rettv->v_type = VAR_BOOL;
3621 			val = f == 0.0 ? VVAL_TRUE : VVAL_FALSE;
3622 		    }
3623 		    else
3624 			f = !f;
3625 		}
3626 		else
3627 #endif
3628 		{
3629 		    val = !val;
3630 		    type = VAR_BOOL;
3631 		}
3632 	    }
3633 	    else if (*end_leader == '-')
3634 	    {
3635 #ifdef FEAT_FLOAT
3636 		if (rettv->v_type == VAR_FLOAT)
3637 		    f = -f;
3638 		else
3639 #endif
3640 		{
3641 		    val = -val;
3642 		    type = VAR_NUMBER;
3643 		}
3644 	    }
3645 	}
3646 #ifdef FEAT_FLOAT
3647 	if (rettv->v_type == VAR_FLOAT)
3648 	{
3649 	    clear_tv(rettv);
3650 	    rettv->vval.v_float = f;
3651 	}
3652 	else
3653 #endif
3654 	{
3655 	    clear_tv(rettv);
3656 	    if (in_vim9script())
3657 		rettv->v_type = type;
3658 	    else
3659 		rettv->v_type = VAR_NUMBER;
3660 	    rettv->vval.v_number = val;
3661 	}
3662     }
3663     *end_leaderp = end_leader;
3664     return ret;
3665 }
3666 
3667 /*
3668  * Call the function referred to in "rettv".
3669  */
3670     static int
3671 call_func_rettv(
3672 	char_u	    **arg,
3673 	evalarg_T   *evalarg,
3674 	typval_T    *rettv,
3675 	int	    evaluate,
3676 	dict_T	    *selfdict,
3677 	typval_T    *basetv)
3678 {
3679     partial_T	*pt = NULL;
3680     funcexe_T	funcexe;
3681     typval_T	functv;
3682     char_u	*s;
3683     int		ret;
3684 
3685     // need to copy the funcref so that we can clear rettv
3686     if (evaluate)
3687     {
3688 	functv = *rettv;
3689 	rettv->v_type = VAR_UNKNOWN;
3690 
3691 	// Invoke the function.  Recursive!
3692 	if (functv.v_type == VAR_PARTIAL)
3693 	{
3694 	    pt = functv.vval.v_partial;
3695 	    s = partial_name(pt);
3696 	}
3697 	else
3698 	    s = functv.vval.v_string;
3699     }
3700     else
3701 	s = (char_u *)"";
3702 
3703     CLEAR_FIELD(funcexe);
3704     funcexe.firstline = curwin->w_cursor.lnum;
3705     funcexe.lastline = curwin->w_cursor.lnum;
3706     funcexe.evaluate = evaluate;
3707     funcexe.partial = pt;
3708     funcexe.selfdict = selfdict;
3709     funcexe.basetv = basetv;
3710     ret = get_func_tv(s, -1, rettv, arg, evalarg, &funcexe);
3711 
3712     // Clear the funcref afterwards, so that deleting it while
3713     // evaluating the arguments is possible (see test55).
3714     if (evaluate)
3715 	clear_tv(&functv);
3716 
3717     return ret;
3718 }
3719 
3720 /*
3721  * Evaluate "->method()".
3722  * "*arg" points to "method".
3723  * Returns FAIL or OK. "*arg" is advanced to after the ')'.
3724  */
3725     static int
3726 eval_lambda(
3727     char_u	**arg,
3728     typval_T	*rettv,
3729     evalarg_T	*evalarg,
3730     int		verbose)	// give error messages
3731 {
3732     int		evaluate = evalarg != NULL
3733 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3734     typval_T	base = *rettv;
3735     int		ret;
3736 
3737     rettv->v_type = VAR_UNKNOWN;
3738 
3739     if (**arg == '{')
3740     {
3741 	// ->{lambda}()
3742 	ret = get_lambda_tv(arg, rettv, FALSE, evalarg);
3743     }
3744     else
3745     {
3746 	// ->(lambda)()
3747 	++*arg;
3748 	ret = eval1(arg, rettv, evalarg);
3749 	*arg = skipwhite_and_linebreak(*arg, evalarg);
3750 	if (**arg != ')')
3751 	{
3752 	    emsg(_(e_missing_close));
3753 	    ret = FAIL;
3754 	}
3755 	++*arg;
3756     }
3757     if (ret != OK)
3758 	return FAIL;
3759     else if (**arg != '(')
3760     {
3761 	if (verbose)
3762 	{
3763 	    if (*skipwhite(*arg) == '(')
3764 		emsg(_(e_nowhitespace));
3765 	    else
3766 		semsg(_(e_missing_paren), "lambda");
3767 	}
3768 	clear_tv(rettv);
3769 	ret = FAIL;
3770     }
3771     else
3772 	ret = call_func_rettv(arg, evalarg, rettv, evaluate, NULL, &base);
3773 
3774     // Clear the funcref afterwards, so that deleting it while
3775     // evaluating the arguments is possible (see test55).
3776     if (evaluate)
3777 	clear_tv(&base);
3778 
3779     return ret;
3780 }
3781 
3782 /*
3783  * Evaluate "->method()".
3784  * "*arg" points to "method".
3785  * Returns FAIL or OK. "*arg" is advanced to after the ')'.
3786  */
3787     static int
3788 eval_method(
3789     char_u	**arg,
3790     typval_T	*rettv,
3791     evalarg_T	*evalarg,
3792     int		verbose)	// give error messages
3793 {
3794     char_u	*name;
3795     long	len;
3796     char_u	*alias;
3797     typval_T	base = *rettv;
3798     int		ret;
3799     int		evaluate = evalarg != NULL
3800 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3801 
3802     rettv->v_type = VAR_UNKNOWN;
3803 
3804     name = *arg;
3805     len = get_name_len(arg, &alias, evaluate, TRUE);
3806     if (alias != NULL)
3807 	name = alias;
3808 
3809     if (len <= 0)
3810     {
3811 	if (verbose)
3812 	    emsg(_("E260: Missing name after ->"));
3813 	ret = FAIL;
3814     }
3815     else
3816     {
3817 	*arg = skipwhite(*arg);
3818 	if (**arg != '(')
3819 	{
3820 	    if (verbose)
3821 		semsg(_(e_missing_paren), name);
3822 	    ret = FAIL;
3823 	}
3824 	else if (VIM_ISWHITE((*arg)[-1]))
3825 	{
3826 	    if (verbose)
3827 		emsg(_(e_nowhitespace));
3828 	    ret = FAIL;
3829 	}
3830 	else
3831 	    ret = eval_func(arg, evalarg, name, len, rettv,
3832 					  evaluate ? EVAL_EVALUATE : 0, &base);
3833     }
3834 
3835     // Clear the funcref afterwards, so that deleting it while
3836     // evaluating the arguments is possible (see test55).
3837     if (evaluate)
3838 	clear_tv(&base);
3839 
3840     return ret;
3841 }
3842 
3843 /*
3844  * Evaluate an "[expr]" or "[expr:expr]" index.  Also "dict.key".
3845  * "*arg" points to the '[' or '.'.
3846  * Returns FAIL or OK. "*arg" is advanced to after the ']'.
3847  */
3848     static int
3849 eval_index(
3850     char_u	**arg,
3851     typval_T	*rettv,
3852     evalarg_T	*evalarg,
3853     int		verbose)	// give error messages
3854 {
3855     int		evaluate = evalarg != NULL
3856 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3857     int		empty1 = FALSE, empty2 = FALSE;
3858     typval_T	var1, var2;
3859     int		range = FALSE;
3860     char_u	*key = NULL;
3861     int		keylen = -1;
3862     int		vim9 = in_vim9script();
3863 
3864     if (check_can_index(rettv, evaluate, verbose) == FAIL)
3865 	return FAIL;
3866 
3867     init_tv(&var1);
3868     init_tv(&var2);
3869     if (**arg == '.')
3870     {
3871 	/*
3872 	 * dict.name
3873 	 */
3874 	key = *arg + 1;
3875 	for (keylen = 0; eval_isdictc(key[keylen]); ++keylen)
3876 	    ;
3877 	if (keylen == 0)
3878 	    return FAIL;
3879 	*arg = key + keylen;
3880     }
3881     else
3882     {
3883 	/*
3884 	 * something[idx]
3885 	 *
3886 	 * Get the (first) variable from inside the [].
3887 	 */
3888 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3889 	if (**arg == ':')
3890 	    empty1 = TRUE;
3891 	else if (eval1(arg, &var1, evalarg) == FAIL)	// recursive!
3892 	    return FAIL;
3893 	else if (vim9 && **arg == ':')
3894 	{
3895 	    semsg(_(e_white_space_required_before_and_after_str_at_str),
3896 								    ":", *arg);
3897 	    clear_tv(&var1);
3898 	    return FAIL;
3899 	}
3900 	else if (evaluate)
3901 	{
3902 #ifdef FEAT_FLOAT
3903 	    // allow for indexing with float
3904 	    if (vim9 && rettv->v_type == VAR_DICT
3905 						   && var1.v_type == VAR_FLOAT)
3906 	    {
3907 		var1.vval.v_string = typval_tostring(&var1, TRUE);
3908 		var1.v_type = VAR_STRING;
3909 	    }
3910 #endif
3911 	    if (tv_get_string_chk(&var1) == NULL)
3912 	    {
3913 		// not a number or string
3914 		clear_tv(&var1);
3915 		return FAIL;
3916 	    }
3917 	}
3918 
3919 	/*
3920 	 * Get the second variable from inside the [:].
3921 	 */
3922 	*arg = skipwhite_and_linebreak(*arg, evalarg);
3923 	if (**arg == ':')
3924 	{
3925 	    range = TRUE;
3926 	    ++*arg;
3927 	    if (vim9 && !IS_WHITE_OR_NUL(**arg) && **arg != ']')
3928 	    {
3929 		semsg(_(e_white_space_required_before_and_after_str_at_str),
3930 								":", *arg - 1);
3931 		if (!empty1)
3932 		    clear_tv(&var1);
3933 		return FAIL;
3934 	    }
3935 	    *arg = skipwhite_and_linebreak(*arg, evalarg);
3936 	    if (**arg == ']')
3937 		empty2 = TRUE;
3938 	    else if (eval1(arg, &var2, evalarg) == FAIL)	// recursive!
3939 	    {
3940 		if (!empty1)
3941 		    clear_tv(&var1);
3942 		return FAIL;
3943 	    }
3944 	    else if (evaluate && tv_get_string_chk(&var2) == NULL)
3945 	    {
3946 		// not a number or string
3947 		if (!empty1)
3948 		    clear_tv(&var1);
3949 		clear_tv(&var2);
3950 		return FAIL;
3951 	    }
3952 	}
3953 
3954 	// Check for the ']'.
3955 	*arg = skipwhite_and_linebreak(*arg, evalarg);
3956 	if (**arg != ']')
3957 	{
3958 	    if (verbose)
3959 		emsg(_(e_missbrac));
3960 	    clear_tv(&var1);
3961 	    if (range)
3962 		clear_tv(&var2);
3963 	    return FAIL;
3964 	}
3965 	*arg = *arg + 1;	// skip over the ']'
3966     }
3967 
3968     if (evaluate)
3969     {
3970 	int res = eval_index_inner(rettv, range,
3971 		empty1 ? NULL : &var1, empty2 ? NULL : &var2, FALSE,
3972 		key, keylen, verbose);
3973 
3974 	if (!empty1)
3975 	    clear_tv(&var1);
3976 	if (range)
3977 	    clear_tv(&var2);
3978 	return res;
3979     }
3980     return OK;
3981 }
3982 
3983 /*
3984  * Check if "rettv" can have an [index] or [sli:ce]
3985  */
3986     int
3987 check_can_index(typval_T *rettv, int evaluate, int verbose)
3988 {
3989     switch (rettv->v_type)
3990     {
3991 	case VAR_FUNC:
3992 	case VAR_PARTIAL:
3993 	    if (verbose)
3994 		emsg(_("E695: Cannot index a Funcref"));
3995 	    return FAIL;
3996 	case VAR_FLOAT:
3997 #ifdef FEAT_FLOAT
3998 	    if (verbose)
3999 		emsg(_(e_float_as_string));
4000 	    return FAIL;
4001 #endif
4002 	case VAR_BOOL:
4003 	case VAR_SPECIAL:
4004 	case VAR_JOB:
4005 	case VAR_CHANNEL:
4006 	    if (verbose)
4007 		emsg(_(e_cannot_index_special_variable));
4008 	    return FAIL;
4009 	case VAR_UNKNOWN:
4010 	case VAR_ANY:
4011 	case VAR_VOID:
4012 	    if (evaluate)
4013 	    {
4014 		emsg(_(e_cannot_index_special_variable));
4015 		return FAIL;
4016 	    }
4017 	    // FALLTHROUGH
4018 
4019 	case VAR_STRING:
4020 	case VAR_LIST:
4021 	case VAR_DICT:
4022 	case VAR_BLOB:
4023 	    break;
4024 	case VAR_NUMBER:
4025 	    if (in_vim9script())
4026 		emsg(_(e_cannot_index_number));
4027 	    break;
4028     }
4029     return OK;
4030 }
4031 
4032 /*
4033  * slice() function
4034  */
4035     void
4036 f_slice(typval_T *argvars, typval_T *rettv)
4037 {
4038     if (check_can_index(argvars, TRUE, FALSE) == OK)
4039     {
4040 	copy_tv(argvars, rettv);
4041 	eval_index_inner(rettv, TRUE, argvars + 1,
4042 		argvars[2].v_type == VAR_UNKNOWN ? NULL : argvars + 2,
4043 		TRUE, NULL, 0, FALSE);
4044     }
4045 }
4046 
4047 /*
4048  * Apply index or range to "rettv".
4049  * "var1" is the first index, NULL for [:expr].
4050  * "var2" is the second index, NULL for [expr] and [expr: ]
4051  * "exclusive" is TRUE for slice(): second index is exclusive, use character
4052  * index for string.
4053  * Alternatively, "key" is not NULL, then key[keylen] is the dict index.
4054  */
4055     int
4056 eval_index_inner(
4057 	typval_T    *rettv,
4058 	int	    is_range,
4059 	typval_T    *var1,
4060 	typval_T    *var2,
4061 	int	    exclusive,
4062 	char_u	    *key,
4063 	int	    keylen,
4064 	int	    verbose)
4065 {
4066     varnumber_T	    n1, n2 = 0;
4067     long	    len;
4068 
4069     n1 = 0;
4070     if (var1 != NULL && rettv->v_type != VAR_DICT)
4071 	n1 = tv_get_number(var1);
4072 
4073     if (is_range)
4074     {
4075 	if (rettv->v_type == VAR_DICT)
4076 	{
4077 	    if (verbose)
4078 		emsg(_(e_cannot_slice_dictionary));
4079 	    return FAIL;
4080 	}
4081 	if (var2 != NULL)
4082 	    n2 = tv_get_number(var2);
4083 	else
4084 	    n2 = VARNUM_MAX;
4085     }
4086 
4087     switch (rettv->v_type)
4088     {
4089 	case VAR_UNKNOWN:
4090 	case VAR_ANY:
4091 	case VAR_VOID:
4092 	case VAR_FUNC:
4093 	case VAR_PARTIAL:
4094 	case VAR_FLOAT:
4095 	case VAR_BOOL:
4096 	case VAR_SPECIAL:
4097 	case VAR_JOB:
4098 	case VAR_CHANNEL:
4099 	    break; // not evaluating, skipping over subscript
4100 
4101 	case VAR_NUMBER:
4102 	case VAR_STRING:
4103 	    {
4104 		char_u	*s = tv_get_string(rettv);
4105 
4106 		len = (long)STRLEN(s);
4107 		if (in_vim9script() || exclusive)
4108 		{
4109 		    if (is_range)
4110 			s = string_slice(s, n1, n2, exclusive);
4111 		    else
4112 			s = char_from_string(s, n1);
4113 		}
4114 		else if (is_range)
4115 		{
4116 		    // The resulting variable is a substring.  If the indexes
4117 		    // are out of range the result is empty.
4118 		    if (n1 < 0)
4119 		    {
4120 			n1 = len + n1;
4121 			if (n1 < 0)
4122 			    n1 = 0;
4123 		    }
4124 		    if (n2 < 0)
4125 			n2 = len + n2;
4126 		    else if (n2 >= len)
4127 			n2 = len;
4128 		    if (n1 >= len || n2 < 0 || n1 > n2)
4129 			s = NULL;
4130 		    else
4131 			s = vim_strnsave(s + n1, n2 - n1 + 1);
4132 		}
4133 		else
4134 		{
4135 		    // The resulting variable is a string of a single
4136 		    // character.  If the index is too big or negative the
4137 		    // result is empty.
4138 		    if (n1 >= len || n1 < 0)
4139 			s = NULL;
4140 		    else
4141 			s = vim_strnsave(s + n1, 1);
4142 		}
4143 		clear_tv(rettv);
4144 		rettv->v_type = VAR_STRING;
4145 		rettv->vval.v_string = s;
4146 	    }
4147 	    break;
4148 
4149 	case VAR_BLOB:
4150 	    len = blob_len(rettv->vval.v_blob);
4151 	    if (is_range)
4152 	    {
4153 		// The resulting variable is a sub-blob.  If the indexes
4154 		// are out of range the result is empty.
4155 		if (n1 < 0)
4156 		{
4157 		    n1 = len + n1;
4158 		    if (n1 < 0)
4159 			n1 = 0;
4160 		}
4161 		if (n2 < 0)
4162 		    n2 = len + n2;
4163 		else if (n2 >= len)
4164 		    n2 = len - (exclusive ? 0 : 1);
4165 		if (exclusive)
4166 		    --n2;
4167 		if (n1 >= len || n2 < 0 || n1 > n2)
4168 		{
4169 		    clear_tv(rettv);
4170 		    rettv->v_type = VAR_BLOB;
4171 		    rettv->vval.v_blob = NULL;
4172 		}
4173 		else
4174 		{
4175 		    blob_T  *blob = blob_alloc();
4176 		    long    i;
4177 
4178 		    if (blob != NULL)
4179 		    {
4180 			if (ga_grow(&blob->bv_ga, n2 - n1 + 1) == FAIL)
4181 			{
4182 			    blob_free(blob);
4183 			    return FAIL;
4184 			}
4185 			blob->bv_ga.ga_len = n2 - n1 + 1;
4186 			for (i = n1; i <= n2; i++)
4187 			    blob_set(blob, i - n1,
4188 					  blob_get(rettv->vval.v_blob, i));
4189 
4190 			clear_tv(rettv);
4191 			rettv_blob_set(rettv, blob);
4192 		    }
4193 		}
4194 	    }
4195 	    else
4196 	    {
4197 		// The resulting variable is a byte value.
4198 		// If the index is too big or negative that is an error.
4199 		if (n1 < 0)
4200 		    n1 = len + n1;
4201 		if (n1 < len && n1 >= 0)
4202 		{
4203 		    int v = blob_get(rettv->vval.v_blob, n1);
4204 
4205 		    clear_tv(rettv);
4206 		    rettv->v_type = VAR_NUMBER;
4207 		    rettv->vval.v_number = v;
4208 		}
4209 		else
4210 		    semsg(_(e_blobidx), n1);
4211 	    }
4212 	    break;
4213 
4214 	case VAR_LIST:
4215 	    if (var1 == NULL)
4216 		n1 = 0;
4217 	    if (var2 == NULL)
4218 		n2 = VARNUM_MAX;
4219 	    if (list_slice_or_index(rettv->vval.v_list,
4220 			  is_range, n1, n2, exclusive, rettv, verbose) == FAIL)
4221 		return FAIL;
4222 	    break;
4223 
4224 	case VAR_DICT:
4225 	    {
4226 		dictitem_T	*item;
4227 		typval_T	tmp;
4228 
4229 		if (key == NULL)
4230 		{
4231 		    key = tv_get_string_chk(var1);
4232 		    if (key == NULL)
4233 			return FAIL;
4234 		}
4235 
4236 		item = dict_find(rettv->vval.v_dict, key, (int)keylen);
4237 
4238 		if (item == NULL && verbose)
4239 		    semsg(_(e_dictkey), key);
4240 		if (item == NULL)
4241 		    return FAIL;
4242 
4243 		copy_tv(&item->di_tv, &tmp);
4244 		clear_tv(rettv);
4245 		*rettv = tmp;
4246 	    }
4247 	    break;
4248     }
4249     return OK;
4250 }
4251 
4252 /*
4253  * Return the function name of partial "pt".
4254  */
4255     char_u *
4256 partial_name(partial_T *pt)
4257 {
4258     if (pt->pt_name != NULL)
4259 	return pt->pt_name;
4260     if (pt->pt_func != NULL)
4261 	return pt->pt_func->uf_name;
4262     return (char_u *)"";
4263 }
4264 
4265     static void
4266 partial_free(partial_T *pt)
4267 {
4268     int i;
4269 
4270     for (i = 0; i < pt->pt_argc; ++i)
4271 	clear_tv(&pt->pt_argv[i]);
4272     vim_free(pt->pt_argv);
4273     dict_unref(pt->pt_dict);
4274     if (pt->pt_name != NULL)
4275     {
4276 	func_unref(pt->pt_name);
4277 	vim_free(pt->pt_name);
4278     }
4279     else
4280 	func_ptr_unref(pt->pt_func);
4281 
4282     // Decrease the reference count for the context of a closure.  If down
4283     // to the minimum it may be time to free it.
4284     if (pt->pt_funcstack != NULL)
4285     {
4286 	--pt->pt_funcstack->fs_refcount;
4287 	funcstack_check_refcount(pt->pt_funcstack);
4288     }
4289 
4290     vim_free(pt);
4291 }
4292 
4293 /*
4294  * Unreference a closure: decrement the reference count and free it when it
4295  * becomes zero.
4296  */
4297     void
4298 partial_unref(partial_T *pt)
4299 {
4300     if (pt != NULL)
4301     {
4302 	if (--pt->pt_refcount <= 0)
4303 	    partial_free(pt);
4304 
4305 	// If the reference count goes down to one, the funcstack may be the
4306 	// only reference and can be freed if no other partials reference it.
4307 	else if (pt->pt_refcount == 1 && pt->pt_funcstack != NULL)
4308 	    funcstack_check_refcount(pt->pt_funcstack);
4309     }
4310 }
4311 
4312 /*
4313  * Return the next (unique) copy ID.
4314  * Used for serializing nested structures.
4315  */
4316     int
4317 get_copyID(void)
4318 {
4319     current_copyID += COPYID_INC;
4320     return current_copyID;
4321 }
4322 
4323 /*
4324  * Garbage collection for lists and dictionaries.
4325  *
4326  * We use reference counts to be able to free most items right away when they
4327  * are no longer used.  But for composite items it's possible that it becomes
4328  * unused while the reference count is > 0: When there is a recursive
4329  * reference.  Example:
4330  *	:let l = [1, 2, 3]
4331  *	:let d = {9: l}
4332  *	:let l[1] = d
4333  *
4334  * Since this is quite unusual we handle this with garbage collection: every
4335  * once in a while find out which lists and dicts are not referenced from any
4336  * variable.
4337  *
4338  * Here is a good reference text about garbage collection (refers to Python
4339  * but it applies to all reference-counting mechanisms):
4340  *	http://python.ca/nas/python/gc/
4341  */
4342 
4343 /*
4344  * Do garbage collection for lists and dicts.
4345  * When "testing" is TRUE this is called from test_garbagecollect_now().
4346  * Return TRUE if some memory was freed.
4347  */
4348     int
4349 garbage_collect(int testing)
4350 {
4351     int		copyID;
4352     int		abort = FALSE;
4353     buf_T	*buf;
4354     win_T	*wp;
4355     int		did_free = FALSE;
4356     tabpage_T	*tp;
4357 
4358     if (!testing)
4359     {
4360 	// Only do this once.
4361 	want_garbage_collect = FALSE;
4362 	may_garbage_collect = FALSE;
4363 	garbage_collect_at_exit = FALSE;
4364     }
4365 
4366     // The execution stack can grow big, limit the size.
4367     if (exestack.ga_maxlen - exestack.ga_len > 500)
4368     {
4369 	size_t	new_len;
4370 	char_u	*pp;
4371 	int	n;
4372 
4373 	// Keep 150% of the current size, with a minimum of the growth size.
4374 	n = exestack.ga_len / 2;
4375 	if (n < exestack.ga_growsize)
4376 	    n = exestack.ga_growsize;
4377 
4378 	// Don't make it bigger though.
4379 	if (exestack.ga_len + n < exestack.ga_maxlen)
4380 	{
4381 	    new_len = exestack.ga_itemsize * (exestack.ga_len + n);
4382 	    pp = vim_realloc(exestack.ga_data, new_len);
4383 	    if (pp == NULL)
4384 		return FAIL;
4385 	    exestack.ga_maxlen = exestack.ga_len + n;
4386 	    exestack.ga_data = pp;
4387 	}
4388     }
4389 
4390     // We advance by two because we add one for items referenced through
4391     // previous_funccal.
4392     copyID = get_copyID();
4393 
4394     /*
4395      * 1. Go through all accessible variables and mark all lists and dicts
4396      *    with copyID.
4397      */
4398 
4399     // Don't free variables in the previous_funccal list unless they are only
4400     // referenced through previous_funccal.  This must be first, because if
4401     // the item is referenced elsewhere the funccal must not be freed.
4402     abort = abort || set_ref_in_previous_funccal(copyID);
4403 
4404     // script-local variables
4405     abort = abort || garbage_collect_scriptvars(copyID);
4406 
4407     // buffer-local variables
4408     FOR_ALL_BUFFERS(buf)
4409 	abort = abort || set_ref_in_item(&buf->b_bufvar.di_tv, copyID,
4410 								  NULL, NULL);
4411 
4412     // window-local variables
4413     FOR_ALL_TAB_WINDOWS(tp, wp)
4414 	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
4415 								  NULL, NULL);
4416     if (aucmd_win != NULL)
4417 	abort = abort || set_ref_in_item(&aucmd_win->w_winvar.di_tv, copyID,
4418 								  NULL, NULL);
4419 #ifdef FEAT_PROP_POPUP
4420     FOR_ALL_POPUPWINS(wp)
4421 	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
4422 								  NULL, NULL);
4423     FOR_ALL_TABPAGES(tp)
4424 	FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
4425 		abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
4426 								  NULL, NULL);
4427 #endif
4428 
4429     // tabpage-local variables
4430     FOR_ALL_TABPAGES(tp)
4431 	abort = abort || set_ref_in_item(&tp->tp_winvar.di_tv, copyID,
4432 								  NULL, NULL);
4433     // global variables
4434     abort = abort || garbage_collect_globvars(copyID);
4435 
4436     // function-local variables
4437     abort = abort || set_ref_in_call_stack(copyID);
4438 
4439     // named functions (matters for closures)
4440     abort = abort || set_ref_in_functions(copyID);
4441 
4442     // function call arguments, if v:testing is set.
4443     abort = abort || set_ref_in_func_args(copyID);
4444 
4445     // v: vars
4446     abort = abort || garbage_collect_vimvars(copyID);
4447 
4448     // callbacks in buffers
4449     abort = abort || set_ref_in_buffers(copyID);
4450 
4451 #ifdef FEAT_LUA
4452     abort = abort || set_ref_in_lua(copyID);
4453 #endif
4454 
4455 #ifdef FEAT_PYTHON
4456     abort = abort || set_ref_in_python(copyID);
4457 #endif
4458 
4459 #ifdef FEAT_PYTHON3
4460     abort = abort || set_ref_in_python3(copyID);
4461 #endif
4462 
4463 #ifdef FEAT_JOB_CHANNEL
4464     abort = abort || set_ref_in_channel(copyID);
4465     abort = abort || set_ref_in_job(copyID);
4466 #endif
4467 #ifdef FEAT_NETBEANS_INTG
4468     abort = abort || set_ref_in_nb_channel(copyID);
4469 #endif
4470 
4471 #ifdef FEAT_TIMERS
4472     abort = abort || set_ref_in_timer(copyID);
4473 #endif
4474 
4475 #ifdef FEAT_QUICKFIX
4476     abort = abort || set_ref_in_quickfix(copyID);
4477 #endif
4478 
4479 #ifdef FEAT_TERMINAL
4480     abort = abort || set_ref_in_term(copyID);
4481 #endif
4482 
4483 #ifdef FEAT_PROP_POPUP
4484     abort = abort || set_ref_in_popups(copyID);
4485 #endif
4486 
4487     if (!abort)
4488     {
4489 	/*
4490 	 * 2. Free lists and dictionaries that are not referenced.
4491 	 */
4492 	did_free = free_unref_items(copyID);
4493 
4494 	/*
4495 	 * 3. Check if any funccal can be freed now.
4496 	 *    This may call us back recursively.
4497 	 */
4498 	free_unref_funccal(copyID, testing);
4499     }
4500     else if (p_verbose > 0)
4501     {
4502 	verb_msg(_("Not enough memory to set references, garbage collection aborted!"));
4503     }
4504 
4505     return did_free;
4506 }
4507 
4508 /*
4509  * Free lists, dictionaries, channels and jobs that are no longer referenced.
4510  */
4511     static int
4512 free_unref_items(int copyID)
4513 {
4514     int		did_free = FALSE;
4515 
4516     // Let all "free" functions know that we are here.  This means no
4517     // dictionaries, lists, channels or jobs are to be freed, because we will
4518     // do that here.
4519     in_free_unref_items = TRUE;
4520 
4521     /*
4522      * PASS 1: free the contents of the items.  We don't free the items
4523      * themselves yet, so that it is possible to decrement refcount counters
4524      */
4525 
4526     // Go through the list of dicts and free items without the copyID.
4527     did_free |= dict_free_nonref(copyID);
4528 
4529     // Go through the list of lists and free items without the copyID.
4530     did_free |= list_free_nonref(copyID);
4531 
4532 #ifdef FEAT_JOB_CHANNEL
4533     // Go through the list of jobs and free items without the copyID. This
4534     // must happen before doing channels, because jobs refer to channels, but
4535     // the reference from the channel to the job isn't tracked.
4536     did_free |= free_unused_jobs_contents(copyID, COPYID_MASK);
4537 
4538     // Go through the list of channels and free items without the copyID.
4539     did_free |= free_unused_channels_contents(copyID, COPYID_MASK);
4540 #endif
4541 
4542     /*
4543      * PASS 2: free the items themselves.
4544      */
4545     dict_free_items(copyID);
4546     list_free_items(copyID);
4547 
4548 #ifdef FEAT_JOB_CHANNEL
4549     // Go through the list of jobs and free items without the copyID. This
4550     // must happen before doing channels, because jobs refer to channels, but
4551     // the reference from the channel to the job isn't tracked.
4552     free_unused_jobs(copyID, COPYID_MASK);
4553 
4554     // Go through the list of channels and free items without the copyID.
4555     free_unused_channels(copyID, COPYID_MASK);
4556 #endif
4557 
4558     in_free_unref_items = FALSE;
4559 
4560     return did_free;
4561 }
4562 
4563 /*
4564  * Mark all lists and dicts referenced through hashtab "ht" with "copyID".
4565  * "list_stack" is used to add lists to be marked.  Can be NULL.
4566  *
4567  * Returns TRUE if setting references failed somehow.
4568  */
4569     int
4570 set_ref_in_ht(hashtab_T *ht, int copyID, list_stack_T **list_stack)
4571 {
4572     int		todo;
4573     int		abort = FALSE;
4574     hashitem_T	*hi;
4575     hashtab_T	*cur_ht;
4576     ht_stack_T	*ht_stack = NULL;
4577     ht_stack_T	*tempitem;
4578 
4579     cur_ht = ht;
4580     for (;;)
4581     {
4582 	if (!abort)
4583 	{
4584 	    // Mark each item in the hashtab.  If the item contains a hashtab
4585 	    // it is added to ht_stack, if it contains a list it is added to
4586 	    // list_stack.
4587 	    todo = (int)cur_ht->ht_used;
4588 	    for (hi = cur_ht->ht_array; todo > 0; ++hi)
4589 		if (!HASHITEM_EMPTY(hi))
4590 		{
4591 		    --todo;
4592 		    abort = abort || set_ref_in_item(&HI2DI(hi)->di_tv, copyID,
4593 						       &ht_stack, list_stack);
4594 		}
4595 	}
4596 
4597 	if (ht_stack == NULL)
4598 	    break;
4599 
4600 	// take an item from the stack
4601 	cur_ht = ht_stack->ht;
4602 	tempitem = ht_stack;
4603 	ht_stack = ht_stack->prev;
4604 	free(tempitem);
4605     }
4606 
4607     return abort;
4608 }
4609 
4610 /*
4611  * Mark a dict and its items with "copyID".
4612  * Returns TRUE if setting references failed somehow.
4613  */
4614     int
4615 set_ref_in_dict(dict_T *d, int copyID)
4616 {
4617     if (d != NULL && d->dv_copyID != copyID)
4618     {
4619 	d->dv_copyID = copyID;
4620 	return set_ref_in_ht(&d->dv_hashtab, copyID, NULL);
4621     }
4622     return FALSE;
4623 }
4624 
4625 /*
4626  * Mark a list and its items with "copyID".
4627  * Returns TRUE if setting references failed somehow.
4628  */
4629     int
4630 set_ref_in_list(list_T *ll, int copyID)
4631 {
4632     if (ll != NULL && ll->lv_copyID != copyID)
4633     {
4634 	ll->lv_copyID = copyID;
4635 	return set_ref_in_list_items(ll, copyID, NULL);
4636     }
4637     return FALSE;
4638 }
4639 
4640 /*
4641  * Mark all lists and dicts referenced through list "l" with "copyID".
4642  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
4643  *
4644  * Returns TRUE if setting references failed somehow.
4645  */
4646     int
4647 set_ref_in_list_items(list_T *l, int copyID, ht_stack_T **ht_stack)
4648 {
4649     listitem_T	 *li;
4650     int		 abort = FALSE;
4651     list_T	 *cur_l;
4652     list_stack_T *list_stack = NULL;
4653     list_stack_T *tempitem;
4654 
4655     cur_l = l;
4656     for (;;)
4657     {
4658 	if (!abort && cur_l->lv_first != &range_list_item)
4659 	    // Mark each item in the list.  If the item contains a hashtab
4660 	    // it is added to ht_stack, if it contains a list it is added to
4661 	    // list_stack.
4662 	    for (li = cur_l->lv_first; !abort && li != NULL; li = li->li_next)
4663 		abort = abort || set_ref_in_item(&li->li_tv, copyID,
4664 						       ht_stack, &list_stack);
4665 	if (list_stack == NULL)
4666 	    break;
4667 
4668 	// take an item from the stack
4669 	cur_l = list_stack->list;
4670 	tempitem = list_stack;
4671 	list_stack = list_stack->prev;
4672 	free(tempitem);
4673     }
4674 
4675     return abort;
4676 }
4677 
4678 /*
4679  * Mark all lists and dicts referenced through typval "tv" with "copyID".
4680  * "list_stack" is used to add lists to be marked.  Can be NULL.
4681  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
4682  *
4683  * Returns TRUE if setting references failed somehow.
4684  */
4685     int
4686 set_ref_in_item(
4687     typval_T	    *tv,
4688     int		    copyID,
4689     ht_stack_T	    **ht_stack,
4690     list_stack_T    **list_stack)
4691 {
4692     int		abort = FALSE;
4693 
4694     if (tv->v_type == VAR_DICT)
4695     {
4696 	dict_T	*dd = tv->vval.v_dict;
4697 
4698 	if (dd != NULL && dd->dv_copyID != copyID)
4699 	{
4700 	    // Didn't see this dict yet.
4701 	    dd->dv_copyID = copyID;
4702 	    if (ht_stack == NULL)
4703 	    {
4704 		abort = set_ref_in_ht(&dd->dv_hashtab, copyID, list_stack);
4705 	    }
4706 	    else
4707 	    {
4708 		ht_stack_T *newitem = ALLOC_ONE(ht_stack_T);
4709 
4710 		if (newitem == NULL)
4711 		    abort = TRUE;
4712 		else
4713 		{
4714 		    newitem->ht = &dd->dv_hashtab;
4715 		    newitem->prev = *ht_stack;
4716 		    *ht_stack = newitem;
4717 		}
4718 	    }
4719 	}
4720     }
4721     else if (tv->v_type == VAR_LIST)
4722     {
4723 	list_T	*ll = tv->vval.v_list;
4724 
4725 	if (ll != NULL && ll->lv_copyID != copyID)
4726 	{
4727 	    // Didn't see this list yet.
4728 	    ll->lv_copyID = copyID;
4729 	    if (list_stack == NULL)
4730 	    {
4731 		abort = set_ref_in_list_items(ll, copyID, ht_stack);
4732 	    }
4733 	    else
4734 	    {
4735 		list_stack_T *newitem = ALLOC_ONE(list_stack_T);
4736 
4737 		if (newitem == NULL)
4738 		    abort = TRUE;
4739 		else
4740 		{
4741 		    newitem->list = ll;
4742 		    newitem->prev = *list_stack;
4743 		    *list_stack = newitem;
4744 		}
4745 	    }
4746 	}
4747     }
4748     else if (tv->v_type == VAR_FUNC)
4749     {
4750 	abort = set_ref_in_func(tv->vval.v_string, NULL, copyID);
4751     }
4752     else if (tv->v_type == VAR_PARTIAL)
4753     {
4754 	partial_T	*pt = tv->vval.v_partial;
4755 	int		i;
4756 
4757 	if (pt != NULL && pt->pt_copyID != copyID)
4758 	{
4759 	    // Didn't see this partial yet.
4760 	    pt->pt_copyID = copyID;
4761 
4762 	    abort = set_ref_in_func(pt->pt_name, pt->pt_func, copyID);
4763 
4764 	    if (pt->pt_dict != NULL)
4765 	    {
4766 		typval_T dtv;
4767 
4768 		dtv.v_type = VAR_DICT;
4769 		dtv.vval.v_dict = pt->pt_dict;
4770 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4771 	    }
4772 
4773 	    for (i = 0; i < pt->pt_argc; ++i)
4774 		abort = abort || set_ref_in_item(&pt->pt_argv[i], copyID,
4775 							ht_stack, list_stack);
4776 	    if (pt->pt_funcstack != NULL)
4777 	    {
4778 		typval_T    *stack = pt->pt_funcstack->fs_ga.ga_data;
4779 
4780 		for (i = 0; i < pt->pt_funcstack->fs_ga.ga_len; ++i)
4781 		    abort = abort || set_ref_in_item(stack + i, copyID,
4782 							 ht_stack, list_stack);
4783 	    }
4784 
4785 	}
4786     }
4787 #ifdef FEAT_JOB_CHANNEL
4788     else if (tv->v_type == VAR_JOB)
4789     {
4790 	job_T	    *job = tv->vval.v_job;
4791 	typval_T    dtv;
4792 
4793 	if (job != NULL && job->jv_copyID != copyID)
4794 	{
4795 	    job->jv_copyID = copyID;
4796 	    if (job->jv_channel != NULL)
4797 	    {
4798 		dtv.v_type = VAR_CHANNEL;
4799 		dtv.vval.v_channel = job->jv_channel;
4800 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4801 	    }
4802 	    if (job->jv_exit_cb.cb_partial != NULL)
4803 	    {
4804 		dtv.v_type = VAR_PARTIAL;
4805 		dtv.vval.v_partial = job->jv_exit_cb.cb_partial;
4806 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4807 	    }
4808 	}
4809     }
4810     else if (tv->v_type == VAR_CHANNEL)
4811     {
4812 	channel_T   *ch =tv->vval.v_channel;
4813 	ch_part_T   part;
4814 	typval_T    dtv;
4815 	jsonq_T	    *jq;
4816 	cbq_T	    *cq;
4817 
4818 	if (ch != NULL && ch->ch_copyID != copyID)
4819 	{
4820 	    ch->ch_copyID = copyID;
4821 	    for (part = PART_SOCK; part < PART_COUNT; ++part)
4822 	    {
4823 		for (jq = ch->ch_part[part].ch_json_head.jq_next; jq != NULL;
4824 							     jq = jq->jq_next)
4825 		    set_ref_in_item(jq->jq_value, copyID, ht_stack, list_stack);
4826 		for (cq = ch->ch_part[part].ch_cb_head.cq_next; cq != NULL;
4827 							     cq = cq->cq_next)
4828 		    if (cq->cq_callback.cb_partial != NULL)
4829 		    {
4830 			dtv.v_type = VAR_PARTIAL;
4831 			dtv.vval.v_partial = cq->cq_callback.cb_partial;
4832 			set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4833 		    }
4834 		if (ch->ch_part[part].ch_callback.cb_partial != NULL)
4835 		{
4836 		    dtv.v_type = VAR_PARTIAL;
4837 		    dtv.vval.v_partial =
4838 				      ch->ch_part[part].ch_callback.cb_partial;
4839 		    set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4840 		}
4841 	    }
4842 	    if (ch->ch_callback.cb_partial != NULL)
4843 	    {
4844 		dtv.v_type = VAR_PARTIAL;
4845 		dtv.vval.v_partial = ch->ch_callback.cb_partial;
4846 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4847 	    }
4848 	    if (ch->ch_close_cb.cb_partial != NULL)
4849 	    {
4850 		dtv.v_type = VAR_PARTIAL;
4851 		dtv.vval.v_partial = ch->ch_close_cb.cb_partial;
4852 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4853 	    }
4854 	}
4855     }
4856 #endif
4857     return abort;
4858 }
4859 
4860 /*
4861  * Return a string with the string representation of a variable.
4862  * If the memory is allocated "tofree" is set to it, otherwise NULL.
4863  * "numbuf" is used for a number.
4864  * When "copyID" is not NULL replace recursive lists and dicts with "...".
4865  * When both "echo_style" and "composite_val" are FALSE, put quotes around
4866  * strings as "string()", otherwise does not put quotes around strings, as
4867  * ":echo" displays values.
4868  * When "restore_copyID" is FALSE, repeated items in dictionaries and lists
4869  * are replaced with "...".
4870  * May return NULL.
4871  */
4872     char_u *
4873 echo_string_core(
4874     typval_T	*tv,
4875     char_u	**tofree,
4876     char_u	*numbuf,
4877     int		copyID,
4878     int		echo_style,
4879     int		restore_copyID,
4880     int		composite_val)
4881 {
4882     static int	recurse = 0;
4883     char_u	*r = NULL;
4884 
4885     if (recurse >= DICT_MAXNEST)
4886     {
4887 	if (!did_echo_string_emsg)
4888 	{
4889 	    // Only give this message once for a recursive call to avoid
4890 	    // flooding the user with errors.  And stop iterating over lists
4891 	    // and dicts.
4892 	    did_echo_string_emsg = TRUE;
4893 	    emsg(_("E724: variable nested too deep for displaying"));
4894 	}
4895 	*tofree = NULL;
4896 	return (char_u *)"{E724}";
4897     }
4898     ++recurse;
4899 
4900     switch (tv->v_type)
4901     {
4902 	case VAR_STRING:
4903 	    if (echo_style && !composite_val)
4904 	    {
4905 		*tofree = NULL;
4906 		r = tv->vval.v_string;
4907 		if (r == NULL)
4908 		    r = (char_u *)"";
4909 	    }
4910 	    else
4911 	    {
4912 		*tofree = string_quote(tv->vval.v_string, FALSE);
4913 		r = *tofree;
4914 	    }
4915 	    break;
4916 
4917 	case VAR_FUNC:
4918 	    if (echo_style)
4919 	    {
4920 		*tofree = NULL;
4921 		r = tv->vval.v_string;
4922 	    }
4923 	    else
4924 	    {
4925 		*tofree = string_quote(tv->vval.v_string, TRUE);
4926 		r = *tofree;
4927 	    }
4928 	    break;
4929 
4930 	case VAR_PARTIAL:
4931 	    {
4932 		partial_T   *pt = tv->vval.v_partial;
4933 		char_u	    *fname = string_quote(pt == NULL ? NULL
4934 						    : partial_name(pt), FALSE);
4935 		garray_T    ga;
4936 		int	    i;
4937 		char_u	    *tf;
4938 
4939 		ga_init2(&ga, 1, 100);
4940 		ga_concat(&ga, (char_u *)"function(");
4941 		if (fname != NULL)
4942 		{
4943 		    ga_concat(&ga, fname);
4944 		    vim_free(fname);
4945 		}
4946 		if (pt != NULL && pt->pt_argc > 0)
4947 		{
4948 		    ga_concat(&ga, (char_u *)", [");
4949 		    for (i = 0; i < pt->pt_argc; ++i)
4950 		    {
4951 			if (i > 0)
4952 			    ga_concat(&ga, (char_u *)", ");
4953 			ga_concat(&ga,
4954 			     tv2string(&pt->pt_argv[i], &tf, numbuf, copyID));
4955 			vim_free(tf);
4956 		    }
4957 		    ga_concat(&ga, (char_u *)"]");
4958 		}
4959 		if (pt != NULL && pt->pt_dict != NULL)
4960 		{
4961 		    typval_T dtv;
4962 
4963 		    ga_concat(&ga, (char_u *)", ");
4964 		    dtv.v_type = VAR_DICT;
4965 		    dtv.vval.v_dict = pt->pt_dict;
4966 		    ga_concat(&ga, tv2string(&dtv, &tf, numbuf, copyID));
4967 		    vim_free(tf);
4968 		}
4969 		ga_concat(&ga, (char_u *)")");
4970 
4971 		*tofree = ga.ga_data;
4972 		r = *tofree;
4973 		break;
4974 	    }
4975 
4976 	case VAR_BLOB:
4977 	    r = blob2string(tv->vval.v_blob, tofree, numbuf);
4978 	    break;
4979 
4980 	case VAR_LIST:
4981 	    if (tv->vval.v_list == NULL)
4982 	    {
4983 		// NULL list is equivalent to empty list.
4984 		*tofree = NULL;
4985 		r = (char_u *)"[]";
4986 	    }
4987 	    else if (copyID != 0 && tv->vval.v_list->lv_copyID == copyID
4988 		    && tv->vval.v_list->lv_len > 0)
4989 	    {
4990 		*tofree = NULL;
4991 		r = (char_u *)"[...]";
4992 	    }
4993 	    else
4994 	    {
4995 		int old_copyID = tv->vval.v_list->lv_copyID;
4996 
4997 		tv->vval.v_list->lv_copyID = copyID;
4998 		*tofree = list2string(tv, copyID, restore_copyID);
4999 		if (restore_copyID)
5000 		    tv->vval.v_list->lv_copyID = old_copyID;
5001 		r = *tofree;
5002 	    }
5003 	    break;
5004 
5005 	case VAR_DICT:
5006 	    if (tv->vval.v_dict == NULL)
5007 	    {
5008 		// NULL dict is equivalent to empty dict.
5009 		*tofree = NULL;
5010 		r = (char_u *)"{}";
5011 	    }
5012 	    else if (copyID != 0 && tv->vval.v_dict->dv_copyID == copyID
5013 		    && tv->vval.v_dict->dv_hashtab.ht_used != 0)
5014 	    {
5015 		*tofree = NULL;
5016 		r = (char_u *)"{...}";
5017 	    }
5018 	    else
5019 	    {
5020 		int old_copyID = tv->vval.v_dict->dv_copyID;
5021 
5022 		tv->vval.v_dict->dv_copyID = copyID;
5023 		*tofree = dict2string(tv, copyID, restore_copyID);
5024 		if (restore_copyID)
5025 		    tv->vval.v_dict->dv_copyID = old_copyID;
5026 		r = *tofree;
5027 	    }
5028 	    break;
5029 
5030 	case VAR_NUMBER:
5031 	case VAR_UNKNOWN:
5032 	case VAR_ANY:
5033 	case VAR_VOID:
5034 	    *tofree = NULL;
5035 	    r = tv_get_string_buf(tv, numbuf);
5036 	    break;
5037 
5038 	case VAR_JOB:
5039 	case VAR_CHANNEL:
5040 	    *tofree = NULL;
5041 	    r = tv_get_string_buf(tv, numbuf);
5042 	    if (composite_val)
5043 	    {
5044 		*tofree = string_quote(r, FALSE);
5045 		r = *tofree;
5046 	    }
5047 	    break;
5048 
5049 	case VAR_FLOAT:
5050 #ifdef FEAT_FLOAT
5051 	    *tofree = NULL;
5052 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv->vval.v_float);
5053 	    r = numbuf;
5054 	    break;
5055 #endif
5056 
5057 	case VAR_BOOL:
5058 	case VAR_SPECIAL:
5059 	    *tofree = NULL;
5060 	    r = (char_u *)get_var_special_name(tv->vval.v_number);
5061 	    break;
5062     }
5063 
5064     if (--recurse == 0)
5065 	did_echo_string_emsg = FALSE;
5066     return r;
5067 }
5068 
5069 /*
5070  * Return a string with the string representation of a variable.
5071  * If the memory is allocated "tofree" is set to it, otherwise NULL.
5072  * "numbuf" is used for a number.
5073  * Does not put quotes around strings, as ":echo" displays values.
5074  * When "copyID" is not NULL replace recursive lists and dicts with "...".
5075  * May return NULL.
5076  */
5077     char_u *
5078 echo_string(
5079     typval_T	*tv,
5080     char_u	**tofree,
5081     char_u	*numbuf,
5082     int		copyID)
5083 {
5084     return echo_string_core(tv, tofree, numbuf, copyID, TRUE, FALSE, FALSE);
5085 }
5086 
5087 /*
5088  * Return string "str" in ' quotes, doubling ' characters.
5089  * If "str" is NULL an empty string is assumed.
5090  * If "function" is TRUE make it function('string').
5091  */
5092     char_u *
5093 string_quote(char_u *str, int function)
5094 {
5095     unsigned	len;
5096     char_u	*p, *r, *s;
5097 
5098     len = (function ? 13 : 3);
5099     if (str != NULL)
5100     {
5101 	len += (unsigned)STRLEN(str);
5102 	for (p = str; *p != NUL; MB_PTR_ADV(p))
5103 	    if (*p == '\'')
5104 		++len;
5105     }
5106     s = r = alloc(len);
5107     if (r != NULL)
5108     {
5109 	if (function)
5110 	{
5111 	    STRCPY(r, "function('");
5112 	    r += 10;
5113 	}
5114 	else
5115 	    *r++ = '\'';
5116 	if (str != NULL)
5117 	    for (p = str; *p != NUL; )
5118 	    {
5119 		if (*p == '\'')
5120 		    *r++ = '\'';
5121 		MB_COPY_CHAR(p, r);
5122 	    }
5123 	*r++ = '\'';
5124 	if (function)
5125 	    *r++ = ')';
5126 	*r++ = NUL;
5127     }
5128     return s;
5129 }
5130 
5131 #if defined(FEAT_FLOAT) || defined(PROTO)
5132 /*
5133  * Convert the string "text" to a floating point number.
5134  * This uses strtod().  setlocale(LC_NUMERIC, "C") has been used to make sure
5135  * this always uses a decimal point.
5136  * Returns the length of the text that was consumed.
5137  */
5138     int
5139 string2float(
5140     char_u	*text,
5141     float_T	*value)	    // result stored here
5142 {
5143     char	*s = (char *)text;
5144     float_T	f;
5145 
5146     // MS-Windows does not deal with "inf" and "nan" properly.
5147     if (STRNICMP(text, "inf", 3) == 0)
5148     {
5149 	*value = INFINITY;
5150 	return 3;
5151     }
5152     if (STRNICMP(text, "-inf", 3) == 0)
5153     {
5154 	*value = -INFINITY;
5155 	return 4;
5156     }
5157     if (STRNICMP(text, "nan", 3) == 0)
5158     {
5159 	*value = NAN;
5160 	return 3;
5161     }
5162     f = strtod(s, &s);
5163     *value = f;
5164     return (int)((char_u *)s - text);
5165 }
5166 #endif
5167 
5168 /*
5169  * Convert the specified byte index of line 'lnum' in buffer 'buf' to a
5170  * character index.  Works only for loaded buffers. Returns -1 on failure.
5171  * The index of the first byte and the first character is zero.
5172  */
5173     int
5174 buf_byteidx_to_charidx(buf_T *buf, int lnum, int byteidx)
5175 {
5176     char_u	*str;
5177     char_u	*t;
5178     int		count;
5179 
5180     if (buf == NULL || buf->b_ml.ml_mfp == NULL)
5181 	return -1;
5182 
5183     if (lnum > buf->b_ml.ml_line_count)
5184 	lnum = buf->b_ml.ml_line_count;
5185 
5186     str = ml_get_buf(buf, lnum, FALSE);
5187     if (str == NULL)
5188 	return -1;
5189 
5190     if (*str == NUL)
5191 	return 0;
5192 
5193     // count the number of characters
5194     t = str;
5195     for (count = 0; *t != NUL && t <= str + byteidx; count++)
5196 	t += mb_ptr2len(t);
5197 
5198     // In insert mode, when the cursor is at the end of a non-empty line,
5199     // byteidx points to the NUL character immediately past the end of the
5200     // string. In this case, add one to the character count.
5201     if (*t == NUL && byteidx != 0 && t == str + byteidx)
5202 	count++;
5203 
5204     return count - 1;
5205 }
5206 
5207 /*
5208  * Convert the specified character index of line 'lnum' in buffer 'buf' to a
5209  * byte index.  Works only for loaded buffers. Returns -1 on failure.
5210  * The index of the first byte and the first character is zero.
5211  */
5212     int
5213 buf_charidx_to_byteidx(buf_T *buf, int lnum, int charidx)
5214 {
5215     char_u	*str;
5216     char_u	*t;
5217 
5218     if (buf == NULL || buf->b_ml.ml_mfp == NULL)
5219 	return -1;
5220 
5221     if (lnum > buf->b_ml.ml_line_count)
5222 	lnum = buf->b_ml.ml_line_count;
5223 
5224     str = ml_get_buf(buf, lnum, FALSE);
5225     if (str == NULL)
5226 	return -1;
5227 
5228     // Convert the character offset to a byte offset
5229     t = str;
5230     while (*t != NUL && --charidx > 0)
5231 	t += mb_ptr2len(t);
5232 
5233     return t - str;
5234 }
5235 
5236 /*
5237  * Translate a String variable into a position.
5238  * Returns NULL when there is an error.
5239  */
5240     pos_T *
5241 var2fpos(
5242     typval_T	*varp,
5243     int		dollar_lnum,	// TRUE when $ is last line
5244     int		*fnum,		// set to fnum for '0, 'A, etc.
5245     int		charcol)	// return character column
5246 {
5247     char_u		*name;
5248     static pos_T	pos;
5249     pos_T		*pp;
5250 
5251     // Argument can be [lnum, col, coladd].
5252     if (varp->v_type == VAR_LIST)
5253     {
5254 	list_T		*l;
5255 	int		len;
5256 	int		error = FALSE;
5257 	listitem_T	*li;
5258 
5259 	l = varp->vval.v_list;
5260 	if (l == NULL)
5261 	    return NULL;
5262 
5263 	// Get the line number
5264 	pos.lnum = list_find_nr(l, 0L, &error);
5265 	if (error || pos.lnum <= 0 || pos.lnum > curbuf->b_ml.ml_line_count)
5266 	    return NULL;	// invalid line number
5267 	if (charcol)
5268 	    len = (long)mb_charlen(ml_get(pos.lnum));
5269 	else
5270 	    len = (long)STRLEN(ml_get(pos.lnum));
5271 
5272 	// Get the column number
5273 	// We accept "$" for the column number: last column.
5274 	li = list_find(l, 1L);
5275 	if (li != NULL && li->li_tv.v_type == VAR_STRING
5276 		&& li->li_tv.vval.v_string != NULL
5277 		&& STRCMP(li->li_tv.vval.v_string, "$") == 0)
5278 	{
5279 	    pos.col = len + 1;
5280 	}
5281 	else
5282 	{
5283 	    pos.col = list_find_nr(l, 1L, &error);
5284 	    if (error)
5285 		return NULL;
5286 	}
5287 
5288 	// Accept a position up to the NUL after the line.
5289 	if (pos.col == 0 || (int)pos.col > len + 1)
5290 	    return NULL;	// invalid column number
5291 	--pos.col;
5292 
5293 	// Get the virtual offset.  Defaults to zero.
5294 	pos.coladd = list_find_nr(l, 2L, &error);
5295 	if (error)
5296 	    pos.coladd = 0;
5297 
5298 	return &pos;
5299     }
5300 
5301     if (in_vim9script() && check_for_string_arg(varp, 0) == FAIL)
5302 	return NULL;
5303 
5304     name = tv_get_string_chk(varp);
5305     if (name == NULL)
5306 	return NULL;
5307     if (name[0] == '.')				// cursor
5308     {
5309 	pos = curwin->w_cursor;
5310 	if (charcol)
5311 	    pos.col = buf_byteidx_to_charidx(curbuf, pos.lnum, pos.col);
5312 	return &pos;
5313     }
5314     if (name[0] == 'v' && name[1] == NUL)	// Visual start
5315     {
5316 	if (VIsual_active)
5317 	    pos = VIsual;
5318 	else
5319 	    pos = curwin->w_cursor;
5320 	if (charcol)
5321 	    pos.col = buf_byteidx_to_charidx(curbuf, pos.lnum, pos.col);
5322 	return &pos;
5323     }
5324     if (name[0] == '\'')			// mark
5325     {
5326 	pp = getmark_buf_fnum(curbuf, name[1], FALSE, fnum);
5327 	if (pp == NULL || pp == (pos_T *)-1 || pp->lnum <= 0)
5328 	    return NULL;
5329 	if (charcol)
5330 	    pp->col = buf_byteidx_to_charidx(curbuf, pp->lnum, pp->col);
5331 	return pp;
5332     }
5333 
5334     pos.coladd = 0;
5335 
5336     if (name[0] == 'w' && dollar_lnum)
5337     {
5338 	pos.col = 0;
5339 	if (name[1] == '0')		// "w0": first visible line
5340 	{
5341 	    update_topline();
5342 	    // In silent Ex mode topline is zero, but that's not a valid line
5343 	    // number; use one instead.
5344 	    pos.lnum = curwin->w_topline > 0 ? curwin->w_topline : 1;
5345 	    return &pos;
5346 	}
5347 	else if (name[1] == '$')	// "w$": last visible line
5348 	{
5349 	    validate_botline();
5350 	    // In silent Ex mode botline is zero, return zero then.
5351 	    pos.lnum = curwin->w_botline > 0 ? curwin->w_botline - 1 : 0;
5352 	    return &pos;
5353 	}
5354     }
5355     else if (name[0] == '$')		// last column or line
5356     {
5357 	if (dollar_lnum)
5358 	{
5359 	    pos.lnum = curbuf->b_ml.ml_line_count;
5360 	    pos.col = 0;
5361 	}
5362 	else
5363 	{
5364 	    pos.lnum = curwin->w_cursor.lnum;
5365 	    if (charcol)
5366 		pos.col = (colnr_T)mb_charlen(ml_get_curline());
5367 	    else
5368 		pos.col = (colnr_T)STRLEN(ml_get_curline());
5369 	}
5370 	return &pos;
5371     }
5372     return NULL;
5373 }
5374 
5375 /*
5376  * Convert list in "arg" into a position and optional file number.
5377  * When "fnump" is NULL there is no file number, only 3 items.
5378  * Note that the column is passed on as-is, the caller may want to decrement
5379  * it to use 1 for the first column.
5380  * Return FAIL when conversion is not possible, doesn't check the position for
5381  * validity.
5382  */
5383     int
5384 list2fpos(
5385     typval_T	*arg,
5386     pos_T	*posp,
5387     int		*fnump,
5388     colnr_T	*curswantp,
5389     int		charcol)
5390 {
5391     list_T	*l = arg->vval.v_list;
5392     long	i = 0;
5393     long	n;
5394 
5395     // List must be: [fnum, lnum, col, coladd, curswant], where "fnum" is only
5396     // there when "fnump" isn't NULL; "coladd" and "curswant" are optional.
5397     if (arg->v_type != VAR_LIST
5398 	    || l == NULL
5399 	    || l->lv_len < (fnump == NULL ? 2 : 3)
5400 	    || l->lv_len > (fnump == NULL ? 4 : 5))
5401 	return FAIL;
5402 
5403     if (fnump != NULL)
5404     {
5405 	n = list_find_nr(l, i++, NULL);	// fnum
5406 	if (n < 0)
5407 	    return FAIL;
5408 	if (n == 0)
5409 	    n = curbuf->b_fnum;		// current buffer
5410 	*fnump = n;
5411     }
5412 
5413     n = list_find_nr(l, i++, NULL);	// lnum
5414     if (n < 0)
5415 	return FAIL;
5416     posp->lnum = n;
5417 
5418     n = list_find_nr(l, i++, NULL);	// col
5419     if (n < 0)
5420 	return FAIL;
5421     // If character position is specified, then convert to byte position
5422     if (charcol)
5423     {
5424 	buf_T	*buf;
5425 
5426 	// Get the text for the specified line in a loaded buffer
5427 	buf = buflist_findnr(fnump == NULL ? curbuf->b_fnum : *fnump);
5428 	if (buf == NULL || buf->b_ml.ml_mfp == NULL)
5429 	    return FAIL;
5430 
5431 	n = buf_charidx_to_byteidx(buf, posp->lnum, n) + 1;
5432     }
5433     posp->col = n;
5434 
5435     n = list_find_nr(l, i, NULL);	// off
5436     if (n < 0)
5437 	posp->coladd = 0;
5438     else
5439 	posp->coladd = n;
5440 
5441     if (curswantp != NULL)
5442 	*curswantp = list_find_nr(l, i + 1, NULL);  // curswant
5443 
5444     return OK;
5445 }
5446 
5447 /*
5448  * Get the length of an environment variable name.
5449  * Advance "arg" to the first character after the name.
5450  * Return 0 for error.
5451  */
5452     int
5453 get_env_len(char_u **arg)
5454 {
5455     char_u	*p;
5456     int		len;
5457 
5458     for (p = *arg; vim_isIDc(*p); ++p)
5459 	;
5460     if (p == *arg)	    // no name found
5461 	return 0;
5462 
5463     len = (int)(p - *arg);
5464     *arg = p;
5465     return len;
5466 }
5467 
5468 /*
5469  * Get the length of the name of a function or internal variable.
5470  * "arg" is advanced to after the name.
5471  * Return 0 if something is wrong.
5472  */
5473     int
5474 get_id_len(char_u **arg)
5475 {
5476     char_u	*p;
5477     int		len;
5478 
5479     // Find the end of the name.
5480     for (p = *arg; eval_isnamec(*p); ++p)
5481     {
5482 	if (*p == ':')
5483 	{
5484 	    // "s:" is start of "s:var", but "n:" is not and can be used in
5485 	    // slice "[n:]".  Also "xx:" is not a namespace.
5486 	    len = (int)(p - *arg);
5487 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, **arg) == NULL)
5488 		    || len > 1)
5489 		break;
5490 	}
5491     }
5492     if (p == *arg)	    // no name found
5493 	return 0;
5494 
5495     len = (int)(p - *arg);
5496     *arg = p;
5497 
5498     return len;
5499 }
5500 
5501 /*
5502  * Get the length of the name of a variable or function.
5503  * Only the name is recognized, does not handle ".key" or "[idx]".
5504  * "arg" is advanced to the first non-white character after the name.
5505  * Return -1 if curly braces expansion failed.
5506  * Return 0 if something else is wrong.
5507  * If the name contains 'magic' {}'s, expand them and return the
5508  * expanded name in an allocated string via 'alias' - caller must free.
5509  */
5510     int
5511 get_name_len(
5512     char_u	**arg,
5513     char_u	**alias,
5514     int		evaluate,
5515     int		verbose)
5516 {
5517     int		len;
5518     char_u	*p;
5519     char_u	*expr_start;
5520     char_u	*expr_end;
5521 
5522     *alias = NULL;  // default to no alias
5523 
5524     if ((*arg)[0] == K_SPECIAL && (*arg)[1] == KS_EXTRA
5525 						  && (*arg)[2] == (int)KE_SNR)
5526     {
5527 	// hard coded <SNR>, already translated
5528 	*arg += 3;
5529 	return get_id_len(arg) + 3;
5530     }
5531     len = eval_fname_script(*arg);
5532     if (len > 0)
5533     {
5534 	// literal "<SID>", "s:" or "<SNR>"
5535 	*arg += len;
5536     }
5537 
5538     /*
5539      * Find the end of the name; check for {} construction.
5540      */
5541     p = find_name_end(*arg, &expr_start, &expr_end,
5542 					       len > 0 ? 0 : FNE_CHECK_START);
5543     if (expr_start != NULL)
5544     {
5545 	char_u	*temp_string;
5546 
5547 	if (!evaluate)
5548 	{
5549 	    len += (int)(p - *arg);
5550 	    *arg = skipwhite(p);
5551 	    return len;
5552 	}
5553 
5554 	/*
5555 	 * Include any <SID> etc in the expanded string:
5556 	 * Thus the -len here.
5557 	 */
5558 	temp_string = make_expanded_name(*arg - len, expr_start, expr_end, p);
5559 	if (temp_string == NULL)
5560 	    return -1;
5561 	*alias = temp_string;
5562 	*arg = skipwhite(p);
5563 	return (int)STRLEN(temp_string);
5564     }
5565 
5566     len += get_id_len(arg);
5567     // Only give an error when there is something, otherwise it will be
5568     // reported at a higher level.
5569     if (len == 0 && verbose && **arg != NUL)
5570 	semsg(_(e_invexpr2), *arg);
5571 
5572     return len;
5573 }
5574 
5575 /*
5576  * Find the end of a variable or function name, taking care of magic braces.
5577  * If "expr_start" is not NULL then "expr_start" and "expr_end" are set to the
5578  * start and end of the first magic braces item.
5579  * "flags" can have FNE_INCL_BR and FNE_CHECK_START.
5580  * Return a pointer to just after the name.  Equal to "arg" if there is no
5581  * valid name.
5582  */
5583     char_u *
5584 find_name_end(
5585     char_u	*arg,
5586     char_u	**expr_start,
5587     char_u	**expr_end,
5588     int		flags)
5589 {
5590     int		mb_nest = 0;
5591     int		br_nest = 0;
5592     char_u	*p;
5593     int		len;
5594     int		vim9script = in_vim9script();
5595 
5596     if (expr_start != NULL)
5597     {
5598 	*expr_start = NULL;
5599 	*expr_end = NULL;
5600     }
5601 
5602     // Quick check for valid starting character.
5603     if ((flags & FNE_CHECK_START) && !eval_isnamec1(*arg)
5604 						&& (*arg != '{' || vim9script))
5605 	return arg;
5606 
5607     for (p = arg; *p != NUL
5608 		    && (eval_isnamec(*p)
5609 			|| (*p == '{' && !vim9script)
5610 			|| ((flags & FNE_INCL_BR) && (*p == '['
5611 					 || (*p == '.' && eval_isdictc(p[1]))))
5612 			|| mb_nest != 0
5613 			|| br_nest != 0); MB_PTR_ADV(p))
5614     {
5615 	if (*p == '\'')
5616 	{
5617 	    // skip over 'string' to avoid counting [ and ] inside it.
5618 	    for (p = p + 1; *p != NUL && *p != '\''; MB_PTR_ADV(p))
5619 		;
5620 	    if (*p == NUL)
5621 		break;
5622 	}
5623 	else if (*p == '"')
5624 	{
5625 	    // skip over "str\"ing" to avoid counting [ and ] inside it.
5626 	    for (p = p + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
5627 		if (*p == '\\' && p[1] != NUL)
5628 		    ++p;
5629 	    if (*p == NUL)
5630 		break;
5631 	}
5632 	else if (br_nest == 0 && mb_nest == 0 && *p == ':')
5633 	{
5634 	    // "s:" is start of "s:var", but "n:" is not and can be used in
5635 	    // slice "[n:]".  Also "xx:" is not a namespace. But {ns}: is.
5636 	    len = (int)(p - arg);
5637 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, *arg) == NULL)
5638 		    || (len > 1 && p[-1] != '}'))
5639 		break;
5640 	}
5641 
5642 	if (mb_nest == 0)
5643 	{
5644 	    if (*p == '[')
5645 		++br_nest;
5646 	    else if (*p == ']')
5647 		--br_nest;
5648 	}
5649 
5650 	if (br_nest == 0 && !vim9script)
5651 	{
5652 	    if (*p == '{')
5653 	    {
5654 		mb_nest++;
5655 		if (expr_start != NULL && *expr_start == NULL)
5656 		    *expr_start = p;
5657 	    }
5658 	    else if (*p == '}')
5659 	    {
5660 		mb_nest--;
5661 		if (expr_start != NULL && mb_nest == 0 && *expr_end == NULL)
5662 		    *expr_end = p;
5663 	    }
5664 	}
5665     }
5666 
5667     return p;
5668 }
5669 
5670 /*
5671  * Expands out the 'magic' {}'s in a variable/function name.
5672  * Note that this can call itself recursively, to deal with
5673  * constructs like foo{bar}{baz}{bam}
5674  * The four pointer arguments point to "foo{expre}ss{ion}bar"
5675  *			"in_start"      ^
5676  *			"expr_start"	   ^
5677  *			"expr_end"		 ^
5678  *			"in_end"			    ^
5679  *
5680  * Returns a new allocated string, which the caller must free.
5681  * Returns NULL for failure.
5682  */
5683     static char_u *
5684 make_expanded_name(
5685     char_u	*in_start,
5686     char_u	*expr_start,
5687     char_u	*expr_end,
5688     char_u	*in_end)
5689 {
5690     char_u	c1;
5691     char_u	*retval = NULL;
5692     char_u	*temp_result;
5693 
5694     if (expr_end == NULL || in_end == NULL)
5695 	return NULL;
5696     *expr_start	= NUL;
5697     *expr_end = NUL;
5698     c1 = *in_end;
5699     *in_end = NUL;
5700 
5701     temp_result = eval_to_string(expr_start + 1, FALSE);
5702     if (temp_result != NULL)
5703     {
5704 	retval = alloc(STRLEN(temp_result) + (expr_start - in_start)
5705 						   + (in_end - expr_end) + 1);
5706 	if (retval != NULL)
5707 	{
5708 	    STRCPY(retval, in_start);
5709 	    STRCAT(retval, temp_result);
5710 	    STRCAT(retval, expr_end + 1);
5711 	}
5712     }
5713     vim_free(temp_result);
5714 
5715     *in_end = c1;		// put char back for error messages
5716     *expr_start = '{';
5717     *expr_end = '}';
5718 
5719     if (retval != NULL)
5720     {
5721 	temp_result = find_name_end(retval, &expr_start, &expr_end, 0);
5722 	if (expr_start != NULL)
5723 	{
5724 	    // Further expansion!
5725 	    temp_result = make_expanded_name(retval, expr_start,
5726 						       expr_end, temp_result);
5727 	    vim_free(retval);
5728 	    retval = temp_result;
5729 	}
5730     }
5731 
5732     return retval;
5733 }
5734 
5735 /*
5736  * Return TRUE if character "c" can be used in a variable or function name.
5737  * Does not include '{' or '}' for magic braces.
5738  */
5739     int
5740 eval_isnamec(int c)
5741 {
5742     return ASCII_ISALNUM(c) || c == '_' || c == ':' || c == AUTOLOAD_CHAR;
5743 }
5744 
5745 /*
5746  * Return TRUE if character "c" can be used as the first character in a
5747  * variable or function name (excluding '{' and '}').
5748  */
5749     int
5750 eval_isnamec1(int c)
5751 {
5752     return ASCII_ISALPHA(c) || c == '_';
5753 }
5754 
5755 /*
5756  * Return TRUE if character "c" can be used as the first character of a
5757  * dictionary key.
5758  */
5759     int
5760 eval_isdictc(int c)
5761 {
5762     return ASCII_ISALNUM(c) || c == '_';
5763 }
5764 
5765 /*
5766  * Handle:
5767  * - expr[expr], expr[expr:expr] subscript
5768  * - ".name" lookup
5769  * - function call with Funcref variable: func(expr)
5770  * - method call: var->method()
5771  *
5772  * Can all be combined in any order: dict.func(expr)[idx]['func'](expr)->len()
5773  */
5774     int
5775 handle_subscript(
5776     char_u	**arg,
5777     typval_T	*rettv,
5778     evalarg_T	*evalarg,
5779     int		verbose)	// give error messages
5780 {
5781     int		evaluate = evalarg != NULL
5782 				      && (evalarg->eval_flags & EVAL_EVALUATE);
5783     int		ret = OK;
5784     dict_T	*selfdict = NULL;
5785     int		check_white = TRUE;
5786     int		getnext;
5787     char_u	*p;
5788 
5789     while (ret == OK)
5790     {
5791 	// When at the end of the line and ".name" or "->{" or "->X" follows in
5792 	// the next line then consume the line break.
5793 	p = eval_next_non_blank(*arg, evalarg, &getnext);
5794 	if (getnext
5795 	    && ((rettv->v_type == VAR_DICT && *p == '.' && eval_isdictc(p[1]))
5796 		|| (p[0] == '-' && p[1] == '>'
5797 				     && (p[2] == '{' || ASCII_ISALPHA(p[2])))))
5798 	{
5799 	    *arg = eval_next_line(evalarg);
5800 	    p = *arg;
5801 	    check_white = FALSE;
5802 	}
5803 
5804 	if (rettv->v_type == VAR_ANY)
5805 	{
5806 	    char_u	*exp_name;
5807 	    int		cc;
5808 	    int		idx;
5809 	    ufunc_T	*ufunc;
5810 	    type_T	*type;
5811 
5812 	    // Found script from "import * as {name}", script item name must
5813 	    // follow.
5814 	    if (**arg != '.')
5815 	    {
5816 		if (verbose)
5817 		    semsg(_(e_expected_str_but_got_str), "'.'", *arg);
5818 		ret = FAIL;
5819 		break;
5820 	    }
5821 	    ++*arg;
5822 	    if (IS_WHITE_OR_NUL(**arg))
5823 	    {
5824 		if (verbose)
5825 		    emsg(_(e_no_white_space_allowed_after_dot));
5826 		ret = FAIL;
5827 		break;
5828 	    }
5829 
5830 	    // isolate the name
5831 	    exp_name = *arg;
5832 	    while (eval_isnamec(**arg))
5833 		++*arg;
5834 	    cc = **arg;
5835 	    **arg = NUL;
5836 
5837 	    idx = find_exported(rettv->vval.v_number, exp_name, &ufunc, &type,
5838 						  evalarg->eval_cctx, verbose);
5839 	    **arg = cc;
5840 	    *arg = skipwhite(*arg);
5841 
5842 	    if (idx < 0 && ufunc == NULL)
5843 	    {
5844 		ret = FAIL;
5845 		break;
5846 	    }
5847 	    if (idx >= 0)
5848 	    {
5849 		scriptitem_T    *si = SCRIPT_ITEM(rettv->vval.v_number);
5850 		svar_T		*sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;
5851 
5852 		copy_tv(sv->sv_tv, rettv);
5853 	    }
5854 	    else
5855 	    {
5856 		rettv->v_type = VAR_FUNC;
5857 		rettv->vval.v_string = vim_strsave(ufunc->uf_name);
5858 	    }
5859 	}
5860 
5861 	if ((**arg == '(' && (!evaluate || rettv->v_type == VAR_FUNC
5862 			    || rettv->v_type == VAR_PARTIAL))
5863 		    && (!check_white || !VIM_ISWHITE(*(*arg - 1))))
5864 	{
5865 	    ret = call_func_rettv(arg, evalarg, rettv, evaluate,
5866 							       selfdict, NULL);
5867 
5868 	    // Stop the expression evaluation when immediately aborting on
5869 	    // error, or when an interrupt occurred or an exception was thrown
5870 	    // but not caught.
5871 	    if (aborting())
5872 	    {
5873 		if (ret == OK)
5874 		    clear_tv(rettv);
5875 		ret = FAIL;
5876 	    }
5877 	    dict_unref(selfdict);
5878 	    selfdict = NULL;
5879 	}
5880 	else if (p[0] == '-' && p[1] == '>')
5881 	{
5882 	    *arg = skipwhite(p + 2);
5883 	    if (ret == OK)
5884 	    {
5885 		if ((**arg == '{' && !in_vim9script()) || **arg == '(')
5886 		    // expr->{lambda}() or expr->(lambda)()
5887 		    ret = eval_lambda(arg, rettv, evalarg, verbose);
5888 		else
5889 		    // expr->name()
5890 		    ret = eval_method(arg, rettv, evalarg, verbose);
5891 	    }
5892 	}
5893 	// "." is ".name" lookup when we found a dict or when evaluating and
5894 	// scriptversion is at least 2, where string concatenation is "..".
5895 	else if (**arg == '['
5896 		|| (**arg == '.' && (rettv->v_type == VAR_DICT
5897 			|| (!evaluate
5898 			    && (*arg)[1] != '.'
5899 			    && current_sctx.sc_version >= 2))))
5900 	{
5901 	    dict_unref(selfdict);
5902 	    if (rettv->v_type == VAR_DICT)
5903 	    {
5904 		selfdict = rettv->vval.v_dict;
5905 		if (selfdict != NULL)
5906 		    ++selfdict->dv_refcount;
5907 	    }
5908 	    else
5909 		selfdict = NULL;
5910 	    if (eval_index(arg, rettv, evalarg, verbose) == FAIL)
5911 	    {
5912 		clear_tv(rettv);
5913 		ret = FAIL;
5914 	    }
5915 	}
5916 	else
5917 	    break;
5918     }
5919 
5920     // Turn "dict.Func" into a partial for "Func" bound to "dict".
5921     // Don't do this when "Func" is already a partial that was bound
5922     // explicitly (pt_auto is FALSE).
5923     if (selfdict != NULL
5924 	    && (rettv->v_type == VAR_FUNC
5925 		|| (rettv->v_type == VAR_PARTIAL
5926 		    && (rettv->vval.v_partial->pt_auto
5927 			|| rettv->vval.v_partial->pt_dict == NULL))))
5928 	selfdict = make_partial(selfdict, rettv);
5929 
5930     dict_unref(selfdict);
5931     return ret;
5932 }
5933 
5934 /*
5935  * Make a copy of an item.
5936  * Lists and Dictionaries are also copied.  A deep copy if "deep" is set.
5937  * For deepcopy() "copyID" is zero for a full copy or the ID for when a
5938  * reference to an already copied list/dict can be used.
5939  * Returns FAIL or OK.
5940  */
5941     int
5942 item_copy(
5943     typval_T	*from,
5944     typval_T	*to,
5945     int		deep,
5946     int		copyID)
5947 {
5948     static int	recurse = 0;
5949     int		ret = OK;
5950 
5951     if (recurse >= DICT_MAXNEST)
5952     {
5953 	emsg(_("E698: variable nested too deep for making a copy"));
5954 	return FAIL;
5955     }
5956     ++recurse;
5957 
5958     switch (from->v_type)
5959     {
5960 	case VAR_NUMBER:
5961 	case VAR_FLOAT:
5962 	case VAR_STRING:
5963 	case VAR_FUNC:
5964 	case VAR_PARTIAL:
5965 	case VAR_BOOL:
5966 	case VAR_SPECIAL:
5967 	case VAR_JOB:
5968 	case VAR_CHANNEL:
5969 	    copy_tv(from, to);
5970 	    break;
5971 	case VAR_LIST:
5972 	    to->v_type = VAR_LIST;
5973 	    to->v_lock = 0;
5974 	    if (from->vval.v_list == NULL)
5975 		to->vval.v_list = NULL;
5976 	    else if (copyID != 0 && from->vval.v_list->lv_copyID == copyID)
5977 	    {
5978 		// use the copy made earlier
5979 		to->vval.v_list = from->vval.v_list->lv_copylist;
5980 		++to->vval.v_list->lv_refcount;
5981 	    }
5982 	    else
5983 		to->vval.v_list = list_copy(from->vval.v_list, deep, copyID);
5984 	    if (to->vval.v_list == NULL)
5985 		ret = FAIL;
5986 	    break;
5987 	case VAR_BLOB:
5988 	    ret = blob_copy(from->vval.v_blob, to);
5989 	    break;
5990 	case VAR_DICT:
5991 	    to->v_type = VAR_DICT;
5992 	    to->v_lock = 0;
5993 	    if (from->vval.v_dict == NULL)
5994 		to->vval.v_dict = NULL;
5995 	    else if (copyID != 0 && from->vval.v_dict->dv_copyID == copyID)
5996 	    {
5997 		// use the copy made earlier
5998 		to->vval.v_dict = from->vval.v_dict->dv_copydict;
5999 		++to->vval.v_dict->dv_refcount;
6000 	    }
6001 	    else
6002 		to->vval.v_dict = dict_copy(from->vval.v_dict, deep, copyID);
6003 	    if (to->vval.v_dict == NULL)
6004 		ret = FAIL;
6005 	    break;
6006 	case VAR_UNKNOWN:
6007 	case VAR_ANY:
6008 	case VAR_VOID:
6009 	    internal_error_no_abort("item_copy(UNKNOWN)");
6010 	    ret = FAIL;
6011     }
6012     --recurse;
6013     return ret;
6014 }
6015 
6016     void
6017 echo_one(typval_T *rettv, int with_space, int *atstart, int *needclr)
6018 {
6019     char_u	*tofree;
6020     char_u	numbuf[NUMBUFLEN];
6021     char_u	*p = echo_string(rettv, &tofree, numbuf, get_copyID());
6022 
6023     if (*atstart)
6024     {
6025 	*atstart = FALSE;
6026 	// Call msg_start() after eval1(), evaluating the expression
6027 	// may cause a message to appear.
6028 	if (with_space)
6029 	{
6030 	    // Mark the saved text as finishing the line, so that what
6031 	    // follows is displayed on a new line when scrolling back
6032 	    // at the more prompt.
6033 	    msg_sb_eol();
6034 	    msg_start();
6035 	}
6036     }
6037     else if (with_space)
6038 	msg_puts_attr(" ", echo_attr);
6039 
6040     if (p != NULL)
6041 	for ( ; *p != NUL && !got_int; ++p)
6042 	{
6043 	    if (*p == '\n' || *p == '\r' || *p == TAB)
6044 	    {
6045 		if (*p != TAB && *needclr)
6046 		{
6047 		    // remove any text still there from the command
6048 		    msg_clr_eos();
6049 		    *needclr = FALSE;
6050 		}
6051 		msg_putchar_attr(*p, echo_attr);
6052 	    }
6053 	    else
6054 	    {
6055 		if (has_mbyte)
6056 		{
6057 		    int i = (*mb_ptr2len)(p);
6058 
6059 		    (void)msg_outtrans_len_attr(p, i, echo_attr);
6060 		    p += i - 1;
6061 		}
6062 		else
6063 		    (void)msg_outtrans_len_attr(p, 1, echo_attr);
6064 	    }
6065 	}
6066     vim_free(tofree);
6067 }
6068 
6069 /*
6070  * ":echo expr1 ..."	print each argument separated with a space, add a
6071  *			newline at the end.
6072  * ":echon expr1 ..."	print each argument plain.
6073  */
6074     void
6075 ex_echo(exarg_T *eap)
6076 {
6077     char_u	*arg = eap->arg;
6078     typval_T	rettv;
6079     char_u	*p;
6080     int		needclr = TRUE;
6081     int		atstart = TRUE;
6082     int		did_emsg_before = did_emsg;
6083     int		called_emsg_before = called_emsg;
6084     evalarg_T	evalarg;
6085 
6086     fill_evalarg_from_eap(&evalarg, eap, eap->skip);
6087 
6088     if (eap->skip)
6089 	++emsg_skip;
6090     while ((!ends_excmd2(eap->cmd, arg) || *arg == '"') && !got_int)
6091     {
6092 	// If eval1() causes an error message the text from the command may
6093 	// still need to be cleared. E.g., "echo 22,44".
6094 	need_clr_eos = needclr;
6095 
6096 	p = arg;
6097 	if (eval1(&arg, &rettv, &evalarg) == FAIL)
6098 	{
6099 	    /*
6100 	     * Report the invalid expression unless the expression evaluation
6101 	     * has been cancelled due to an aborting error, an interrupt, or an
6102 	     * exception.
6103 	     */
6104 	    if (!aborting() && did_emsg == did_emsg_before
6105 					  && called_emsg == called_emsg_before)
6106 		semsg(_(e_invexpr2), p);
6107 	    need_clr_eos = FALSE;
6108 	    break;
6109 	}
6110 	need_clr_eos = FALSE;
6111 
6112 	if (!eap->skip)
6113 	    echo_one(&rettv, eap->cmdidx == CMD_echo, &atstart, &needclr);
6114 
6115 	clear_tv(&rettv);
6116 	arg = skipwhite(arg);
6117     }
6118     eap->nextcmd = check_nextcmd(arg);
6119     clear_evalarg(&evalarg, eap);
6120 
6121     if (eap->skip)
6122 	--emsg_skip;
6123     else
6124     {
6125 	// remove text that may still be there from the command
6126 	if (needclr)
6127 	    msg_clr_eos();
6128 	if (eap->cmdidx == CMD_echo)
6129 	    msg_end();
6130     }
6131 }
6132 
6133 /*
6134  * ":echohl {name}".
6135  */
6136     void
6137 ex_echohl(exarg_T *eap)
6138 {
6139     echo_attr = syn_name2attr(eap->arg);
6140 }
6141 
6142 /*
6143  * Returns the :echo attribute
6144  */
6145     int
6146 get_echo_attr(void)
6147 {
6148     return echo_attr;
6149 }
6150 
6151 /*
6152  * ":execute expr1 ..."	execute the result of an expression.
6153  * ":echomsg expr1 ..."	Print a message
6154  * ":echoerr expr1 ..."	Print an error
6155  * ":echoconsole expr1 ..." Print a message on stdout
6156  * Each gets spaces around each argument and a newline at the end for
6157  * echo commands
6158  */
6159     void
6160 ex_execute(exarg_T *eap)
6161 {
6162     char_u	*arg = eap->arg;
6163     typval_T	rettv;
6164     int		ret = OK;
6165     char_u	*p;
6166     garray_T	ga;
6167     int		len;
6168 
6169     ga_init2(&ga, 1, 80);
6170 
6171     if (eap->skip)
6172 	++emsg_skip;
6173     while (!ends_excmd2(eap->cmd, arg) || *arg == '"')
6174     {
6175 	ret = eval1_emsg(&arg, &rettv, eap);
6176 	if (ret == FAIL)
6177 	    break;
6178 
6179 	if (!eap->skip)
6180 	{
6181 	    char_u   buf[NUMBUFLEN];
6182 
6183 	    if (eap->cmdidx == CMD_execute)
6184 	    {
6185 		if (rettv.v_type == VAR_CHANNEL || rettv.v_type == VAR_JOB)
6186 		{
6187 		    emsg(_(e_inval_string));
6188 		    p = NULL;
6189 		}
6190 		else
6191 		    p = tv_get_string_buf(&rettv, buf);
6192 	    }
6193 	    else
6194 		p = tv_stringify(&rettv, buf);
6195 	    if (p == NULL)
6196 	    {
6197 		clear_tv(&rettv);
6198 		ret = FAIL;
6199 		break;
6200 	    }
6201 	    len = (int)STRLEN(p);
6202 	    if (ga_grow(&ga, len + 2) == FAIL)
6203 	    {
6204 		clear_tv(&rettv);
6205 		ret = FAIL;
6206 		break;
6207 	    }
6208 	    if (ga.ga_len)
6209 		((char_u *)(ga.ga_data))[ga.ga_len++] = ' ';
6210 	    STRCPY((char_u *)(ga.ga_data) + ga.ga_len, p);
6211 	    ga.ga_len += len;
6212 	}
6213 
6214 	clear_tv(&rettv);
6215 	arg = skipwhite(arg);
6216     }
6217 
6218     if (ret != FAIL && ga.ga_data != NULL)
6219     {
6220 	if (eap->cmdidx == CMD_echomsg || eap->cmdidx == CMD_echoerr)
6221 	{
6222 	    // Mark the already saved text as finishing the line, so that what
6223 	    // follows is displayed on a new line when scrolling back at the
6224 	    // more prompt.
6225 	    msg_sb_eol();
6226 	}
6227 
6228 	if (eap->cmdidx == CMD_echomsg)
6229 	{
6230 	    msg_attr(ga.ga_data, echo_attr);
6231 	    out_flush();
6232 	}
6233 	else if (eap->cmdidx == CMD_echoconsole)
6234 	{
6235 	    ui_write(ga.ga_data, (int)STRLEN(ga.ga_data), TRUE);
6236 	    ui_write((char_u *)"\r\n", 2, TRUE);
6237 	}
6238 	else if (eap->cmdidx == CMD_echoerr)
6239 	{
6240 	    int		save_did_emsg = did_emsg;
6241 
6242 	    // We don't want to abort following commands, restore did_emsg.
6243 	    emsg(ga.ga_data);
6244 	    if (!force_abort)
6245 		did_emsg = save_did_emsg;
6246 	}
6247 	else if (eap->cmdidx == CMD_execute)
6248 	    do_cmdline((char_u *)ga.ga_data,
6249 		       eap->getline, eap->cookie, DOCMD_NOWAIT|DOCMD_VERBOSE);
6250     }
6251 
6252     ga_clear(&ga);
6253 
6254     if (eap->skip)
6255 	--emsg_skip;
6256 
6257     eap->nextcmd = check_nextcmd(arg);
6258 }
6259 
6260 /*
6261  * Skip over the name of an option: "&option", "&g:option" or "&l:option".
6262  * "arg" points to the "&" or '+' when called, to "option" when returning.
6263  * Returns NULL when no option name found.  Otherwise pointer to the char
6264  * after the option name.
6265  */
6266     char_u *
6267 find_option_end(char_u **arg, int *opt_flags)
6268 {
6269     char_u	*p = *arg;
6270 
6271     ++p;
6272     if (*p == 'g' && p[1] == ':')
6273     {
6274 	*opt_flags = OPT_GLOBAL;
6275 	p += 2;
6276     }
6277     else if (*p == 'l' && p[1] == ':')
6278     {
6279 	*opt_flags = OPT_LOCAL;
6280 	p += 2;
6281     }
6282     else
6283 	*opt_flags = 0;
6284 
6285     if (!ASCII_ISALPHA(*p))
6286 	return NULL;
6287     *arg = p;
6288 
6289     if (p[0] == 't' && p[1] == '_' && p[2] != NUL && p[3] != NUL)
6290 	p += 4;	    // termcap option
6291     else
6292 	while (ASCII_ISALPHA(*p))
6293 	    ++p;
6294     return p;
6295 }
6296 
6297 /*
6298  * Display script name where an item was last set.
6299  * Should only be invoked when 'verbose' is non-zero.
6300  */
6301     void
6302 last_set_msg(sctx_T script_ctx)
6303 {
6304     char_u *p;
6305 
6306     if (script_ctx.sc_sid != 0)
6307     {
6308 	p = home_replace_save(NULL, get_scriptname(script_ctx.sc_sid));
6309 	if (p != NULL)
6310 	{
6311 	    verbose_enter();
6312 	    msg_puts(_("\n\tLast set from "));
6313 	    msg_puts((char *)p);
6314 	    if (script_ctx.sc_lnum > 0)
6315 	    {
6316 		msg_puts(_(line_msg));
6317 		msg_outnum((long)script_ctx.sc_lnum);
6318 	    }
6319 	    verbose_leave();
6320 	    vim_free(p);
6321 	}
6322     }
6323 }
6324 
6325 #endif // FEAT_EVAL
6326 
6327 /*
6328  * Perform a substitution on "str" with pattern "pat" and substitute "sub".
6329  * When "sub" is NULL "expr" is used, must be a VAR_FUNC or VAR_PARTIAL.
6330  * "flags" can be "g" to do a global substitute.
6331  * Returns an allocated string, NULL for error.
6332  */
6333     char_u *
6334 do_string_sub(
6335     char_u	*str,
6336     char_u	*pat,
6337     char_u	*sub,
6338     typval_T	*expr,
6339     char_u	*flags)
6340 {
6341     int		sublen;
6342     regmatch_T	regmatch;
6343     int		i;
6344     int		do_all;
6345     char_u	*tail;
6346     char_u	*end;
6347     garray_T	ga;
6348     char_u	*ret;
6349     char_u	*save_cpo;
6350     char_u	*zero_width = NULL;
6351 
6352     // Make 'cpoptions' empty, so that the 'l' flag doesn't work here
6353     save_cpo = p_cpo;
6354     p_cpo = empty_option;
6355 
6356     ga_init2(&ga, 1, 200);
6357 
6358     do_all = (flags[0] == 'g');
6359 
6360     regmatch.rm_ic = p_ic;
6361     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
6362     if (regmatch.regprog != NULL)
6363     {
6364 	tail = str;
6365 	end = str + STRLEN(str);
6366 	while (vim_regexec_nl(&regmatch, str, (colnr_T)(tail - str)))
6367 	{
6368 	    // Skip empty match except for first match.
6369 	    if (regmatch.startp[0] == regmatch.endp[0])
6370 	    {
6371 		if (zero_width == regmatch.startp[0])
6372 		{
6373 		    // avoid getting stuck on a match with an empty string
6374 		    i = mb_ptr2len(tail);
6375 		    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail,
6376 								   (size_t)i);
6377 		    ga.ga_len += i;
6378 		    tail += i;
6379 		    continue;
6380 		}
6381 		zero_width = regmatch.startp[0];
6382 	    }
6383 
6384 	    /*
6385 	     * Get some space for a temporary buffer to do the substitution
6386 	     * into.  It will contain:
6387 	     * - The text up to where the match is.
6388 	     * - The substituted text.
6389 	     * - The text after the match.
6390 	     */
6391 	    sublen = vim_regsub(&regmatch, sub, expr, tail, FALSE, TRUE, FALSE);
6392 	    if (ga_grow(&ga, (int)((end - tail) + sublen -
6393 			    (regmatch.endp[0] - regmatch.startp[0]))) == FAIL)
6394 	    {
6395 		ga_clear(&ga);
6396 		break;
6397 	    }
6398 
6399 	    // copy the text up to where the match is
6400 	    i = (int)(regmatch.startp[0] - tail);
6401 	    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail, (size_t)i);
6402 	    // add the substituted text
6403 	    (void)vim_regsub(&regmatch, sub, expr, (char_u *)ga.ga_data
6404 					  + ga.ga_len + i, TRUE, TRUE, FALSE);
6405 	    ga.ga_len += i + sublen - 1;
6406 	    tail = regmatch.endp[0];
6407 	    if (*tail == NUL)
6408 		break;
6409 	    if (!do_all)
6410 		break;
6411 	}
6412 
6413 	if (ga.ga_data != NULL)
6414 	    STRCPY((char *)ga.ga_data + ga.ga_len, tail);
6415 
6416 	vim_regfree(regmatch.regprog);
6417     }
6418 
6419     ret = vim_strsave(ga.ga_data == NULL ? str : (char_u *)ga.ga_data);
6420     ga_clear(&ga);
6421     if (p_cpo == empty_option)
6422 	p_cpo = save_cpo;
6423     else
6424     {
6425 	// Darn, evaluating {sub} expression or {expr} changed the value.
6426 	// If it's still empty it was changed and restored, need to restore in
6427 	// the complicated way.
6428 	if (*p_cpo == NUL)
6429 	    set_option_value((char_u *)"cpo", 0L, save_cpo, 0);
6430 	free_string_option(save_cpo);
6431     }
6432 
6433     return ret;
6434 }
6435