xref: /vim-8.2.3635/src/eval.c (revision e7b1ea02)
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 static char *e_dictrange = N_("E719: Cannot use [:] with a Dictionary");
24 
25 #define NAMESPACE_CHAR	(char_u *)"abglstvw"
26 
27 /*
28  * When recursively copying lists and dicts we need to remember which ones we
29  * have done to avoid endless recursiveness.  This unique ID is used for that.
30  * The last bit is used for previous_funccal, ignored when comparing.
31  */
32 static int current_copyID = 0;
33 
34 /*
35  * Info used by a ":for" loop.
36  */
37 typedef struct
38 {
39     int		fi_semicolon;	// TRUE if ending in '; var]'
40     int		fi_varcount;	// nr of variables in the list
41     int		fi_break_count;	// nr of line breaks encountered
42     listwatch_T	fi_lw;		// keep an eye on the item used.
43     list_T	*fi_list;	// list being used
44     int		fi_bi;		// index of blob
45     blob_T	*fi_blob;	// blob being used
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  */
63 	varnumber_T
64 num_divide(varnumber_T n1, varnumber_T n2)
65 {
66     varnumber_T	result;
67 
68     if (n2 == 0)	// give an error message?
69     {
70 	if (n1 == 0)
71 	    result = VARNUM_MIN; // similar to NaN
72 	else if (n1 < 0)
73 	    result = -VARNUM_MAX;
74 	else
75 	    result = VARNUM_MAX;
76     }
77     else
78 	result = n1 / n2;
79 
80     return result;
81 }
82 
83 /*
84  * Return "n1" modulus "n2", taking care of dividing by zero.
85  */
86 	varnumber_T
87 num_modulus(varnumber_T n1, varnumber_T n2)
88 {
89     // Give an error when n2 is 0?
90     return (n2 == 0) ? 0 : (n1 % n2);
91 }
92 
93 #if defined(EBCDIC) || defined(PROTO)
94 /*
95  * Compare struct fst by function name.
96  */
97     static int
98 compare_func_name(const void *s1, const void *s2)
99 {
100     struct fst *p1 = (struct fst *)s1;
101     struct fst *p2 = (struct fst *)s2;
102 
103     return STRCMP(p1->f_name, p2->f_name);
104 }
105 
106 /*
107  * Sort the function table by function name.
108  * The sorting of the table above is ASCII dependent.
109  * On machines using EBCDIC we have to sort it.
110  */
111     static void
112 sortFunctions(void)
113 {
114     int		funcCnt = (int)(sizeof(functions) / sizeof(struct fst)) - 1;
115 
116     qsort(functions, (size_t)funcCnt, sizeof(struct fst), compare_func_name);
117 }
118 #endif
119 
120 /*
121  * Initialize the global and v: variables.
122  */
123     void
124 eval_init(void)
125 {
126     evalvars_init();
127     func_init();
128 
129 #ifdef EBCDIC
130     /*
131      * Sort the function table, to enable binary search.
132      */
133     sortFunctions();
134 #endif
135 }
136 
137 #if defined(EXITFREE) || defined(PROTO)
138     void
139 eval_clear(void)
140 {
141     evalvars_clear();
142     free_scriptnames();  // must come after evalvars_clear().
143     free_locales();
144 
145     // autoloaded script names
146     free_autoload_scriptnames();
147 
148     // unreferenced lists and dicts
149     (void)garbage_collect(FALSE);
150 
151     // functions not garbage collected
152     free_all_functions();
153 }
154 #endif
155 
156     void
157 fill_evalarg_from_eap(evalarg_T *evalarg, exarg_T *eap, int skip)
158 {
159     CLEAR_FIELD(*evalarg);
160     evalarg->eval_flags = skip ? 0 : EVAL_EVALUATE;
161     if (eap != NULL && getline_equal(eap->getline, eap->cookie, getsourceline))
162     {
163 	evalarg->eval_getline = eap->getline;
164 	evalarg->eval_cookie = eap->cookie;
165     }
166 }
167 
168 /*
169  * Top level evaluation function, returning a boolean.
170  * Sets "error" to TRUE if there was an error.
171  * Return TRUE or FALSE.
172  */
173     int
174 eval_to_bool(
175     char_u	*arg,
176     int		*error,
177     exarg_T	*eap,
178     int		skip)	    // only parse, don't execute
179 {
180     typval_T	tv;
181     varnumber_T	retval = FALSE;
182     evalarg_T	evalarg;
183 
184     fill_evalarg_from_eap(&evalarg, eap, skip);
185 
186     if (skip)
187 	++emsg_skip;
188     if (eval0(arg, &tv, eap, &evalarg) == FAIL)
189 	*error = TRUE;
190     else
191     {
192 	*error = FALSE;
193 	if (!skip)
194 	{
195 	    retval = (tv_get_number_chk(&tv, error) != 0);
196 	    clear_tv(&tv);
197 	}
198     }
199     if (skip)
200 	--emsg_skip;
201     clear_evalarg(&evalarg, eap);
202 
203     return (int)retval;
204 }
205 
206 /*
207  * Call eval1() and give an error message if not done at a lower level.
208  */
209     static int
210 eval1_emsg(char_u **arg, typval_T *rettv, exarg_T *eap)
211 {
212     char_u	*start = *arg;
213     int		ret;
214     int		did_emsg_before = did_emsg;
215     int		called_emsg_before = called_emsg;
216     evalarg_T	evalarg;
217 
218     fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);
219 
220     ret = eval1(arg, rettv, &evalarg);
221     if (ret == FAIL)
222     {
223 	// Report the invalid expression unless the expression evaluation has
224 	// been cancelled due to an aborting error, an interrupt, or an
225 	// exception, or we already gave a more specific error.
226 	// Also check called_emsg for when using assert_fails().
227 	if (!aborting() && did_emsg == did_emsg_before
228 					  && called_emsg == called_emsg_before)
229 	    semsg(_(e_invexpr2), start);
230     }
231     clear_evalarg(&evalarg, eap);
232     return ret;
233 }
234 
235 /*
236  * Return whether a typval is a valid expression to pass to eval_expr_typval()
237  * or eval_expr_to_bool().  An empty string returns FALSE;
238  */
239     int
240 eval_expr_valid_arg(typval_T *tv)
241 {
242     return tv->v_type != VAR_UNKNOWN
243 	    && (tv->v_type != VAR_STRING
244 		  || (tv->vval.v_string != NULL && *tv->vval.v_string != NUL));
245 }
246 
247 /*
248  * Evaluate an expression, which can be a function, partial or string.
249  * Pass arguments "argv[argc]".
250  * Return the result in "rettv" and OK or FAIL.
251  */
252     int
253 eval_expr_typval(typval_T *expr, typval_T *argv, int argc, typval_T *rettv)
254 {
255     char_u	*s;
256     char_u	buf[NUMBUFLEN];
257     funcexe_T	funcexe;
258 
259     if (expr->v_type == VAR_FUNC)
260     {
261 	s = expr->vval.v_string;
262 	if (s == NULL || *s == NUL)
263 	    return FAIL;
264 	CLEAR_FIELD(funcexe);
265 	funcexe.evaluate = TRUE;
266 	if (call_func(s, -1, rettv, argc, argv, &funcexe) == FAIL)
267 	    return FAIL;
268     }
269     else if (expr->v_type == VAR_PARTIAL)
270     {
271 	partial_T   *partial = expr->vval.v_partial;
272 
273 	if (partial == NULL)
274 	    return FAIL;
275 
276 	if (partial->pt_func != NULL
277 			  && partial->pt_func->uf_def_status != UF_NOT_COMPILED)
278 	{
279 	    if (call_def_function(partial->pt_func, argc, argv,
280 						       partial, rettv) == FAIL)
281 		return FAIL;
282 	}
283 	else
284 	{
285 	    s = partial_name(partial);
286 	    if (s == NULL || *s == NUL)
287 		return FAIL;
288 	    CLEAR_FIELD(funcexe);
289 	    funcexe.evaluate = TRUE;
290 	    funcexe.partial = partial;
291 	    if (call_func(s, -1, rettv, argc, argv, &funcexe) == FAIL)
292 		return FAIL;
293 	}
294     }
295     else
296     {
297 	s = tv_get_string_buf_chk(expr, buf);
298 	if (s == NULL)
299 	    return FAIL;
300 	s = skipwhite(s);
301 	if (eval1_emsg(&s, rettv, NULL) == FAIL)
302 	    return FAIL;
303 	if (*skipwhite(s) != NUL)  // check for trailing chars after expr
304 	{
305 	    clear_tv(rettv);
306 	    semsg(_(e_invexpr2), s);
307 	    return FAIL;
308 	}
309     }
310     return OK;
311 }
312 
313 /*
314  * Like eval_to_bool() but using a typval_T instead of a string.
315  * Works for string, funcref and partial.
316  */
317     int
318 eval_expr_to_bool(typval_T *expr, int *error)
319 {
320     typval_T	rettv;
321     int		res;
322 
323     if (eval_expr_typval(expr, NULL, 0, &rettv) == FAIL)
324     {
325 	*error = TRUE;
326 	return FALSE;
327     }
328     res = (tv_get_number_chk(&rettv, error) != 0);
329     clear_tv(&rettv);
330     return res;
331 }
332 
333 /*
334  * Top level evaluation function, returning a string.  If "skip" is TRUE,
335  * only parsing to "nextcmd" is done, without reporting errors.  Return
336  * pointer to allocated memory, or NULL for failure or when "skip" is TRUE.
337  */
338     char_u *
339 eval_to_string_skip(
340     char_u	*arg,
341     exarg_T	*eap,
342     int		skip)	    // only parse, don't execute
343 {
344     typval_T	tv;
345     char_u	*retval;
346     evalarg_T	evalarg;
347 
348     fill_evalarg_from_eap(&evalarg, eap, skip);
349     if (skip)
350 	++emsg_skip;
351     if (eval0(arg, &tv, eap, &evalarg) == FAIL || skip)
352 	retval = NULL;
353     else
354     {
355 	retval = vim_strsave(tv_get_string(&tv));
356 	clear_tv(&tv);
357     }
358     if (skip)
359 	--emsg_skip;
360     clear_evalarg(&evalarg, eap);
361 
362     return retval;
363 }
364 
365 /*
366  * Skip over an expression at "*pp".
367  * Return FAIL for an error, OK otherwise.
368  */
369     int
370 skip_expr(char_u **pp)
371 {
372     typval_T	rettv;
373 
374     *pp = skipwhite(*pp);
375     return eval1(pp, &rettv, NULL);
376 }
377 
378 /*
379  * Skip over an expression at "*pp".
380  * If in Vim9 script and line breaks are encountered, the lines are
381  * concatenated.  "evalarg->eval_tofree" will be set accordingly.
382  * "arg" is advanced to just after the expression.
383  * "start" is set to the start of the expression, "end" to just after the end.
384  * Also when the expression is copied to allocated memory.
385  * Return FAIL for an error, OK otherwise.
386  */
387     int
388 skip_expr_concatenate(
389 	char_u	    **arg,
390 	char_u	    **start,
391 	char_u	    **end,
392 	evalarg_T   *evalarg)
393 {
394     typval_T	rettv;
395     int		res;
396     int		vim9script = in_vim9script();
397     garray_T    *gap = &evalarg->eval_ga;
398     int		save_flags = evalarg == NULL ? 0 : evalarg->eval_flags;
399 
400     if (vim9script
401 	       && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL))
402     {
403 	ga_init2(gap, sizeof(char_u *), 10);
404 	// leave room for "start"
405 	if (ga_grow(gap, 1) == OK)
406 	    ++gap->ga_len;
407     }
408     *start = *arg;
409 
410     // Don't evaluate the expression.
411     if (evalarg != NULL)
412 	evalarg->eval_flags &= ~EVAL_EVALUATE;
413     *arg = skipwhite(*arg);
414     res = eval1(arg, &rettv, evalarg);
415     *end = *arg;
416     if (evalarg != NULL)
417 	evalarg->eval_flags = save_flags;
418 
419     if (vim9script
420 	    && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL))
421     {
422 	if (evalarg->eval_ga.ga_len == 1)
423 	{
424 	    // just one line, no need to concatenate
425 	    ga_clear(gap);
426 	    gap->ga_itemsize = 0;
427 	}
428 	else
429 	{
430 	    char_u	    *p;
431 	    size_t	    endoff = STRLEN(*arg);
432 
433 	    // Line breaks encountered, concatenate all the lines.
434 	    *((char_u **)gap->ga_data) = *start;
435 	    p = ga_concat_strings(gap, "");
436 
437 	    // free the lines only when using getsourceline()
438 	    if (evalarg->eval_cookie != NULL)
439 	    {
440 		// Do not free the first line, the caller can still use it.
441 		*((char_u **)gap->ga_data) = NULL;
442 		// Do not free the last line, "arg" points into it, free it
443 		// later.
444 		vim_free(evalarg->eval_tofree);
445 		evalarg->eval_tofree =
446 				    ((char_u **)gap->ga_data)[gap->ga_len - 1];
447 		((char_u **)gap->ga_data)[gap->ga_len - 1] = NULL;
448 		ga_clear_strings(gap);
449 	    }
450 	    else
451 		ga_clear(gap);
452 	    gap->ga_itemsize = 0;
453 	    if (p == NULL)
454 		return FAIL;
455 	    *start = p;
456 	    vim_free(evalarg->eval_tofree_lambda);
457 	    evalarg->eval_tofree_lambda = p;
458 	    // Compute "end" relative to the end.
459 	    *end = *start + STRLEN(*start) - endoff;
460 	}
461     }
462 
463     return res;
464 }
465 
466 /*
467  * Top level evaluation function, returning a string.  Does not handle line
468  * breaks.
469  * When "convert" is TRUE convert a List into a sequence of lines and convert
470  * a Float to a String.
471  * Return pointer to allocated memory, or NULL for failure.
472  */
473     char_u *
474 eval_to_string(
475     char_u	*arg,
476     int		convert)
477 {
478     typval_T	tv;
479     char_u	*retval;
480     garray_T	ga;
481 #ifdef FEAT_FLOAT
482     char_u	numbuf[NUMBUFLEN];
483 #endif
484 
485     if (eval0(arg, &tv, NULL, &EVALARG_EVALUATE) == FAIL)
486 	retval = NULL;
487     else
488     {
489 	if (convert && tv.v_type == VAR_LIST)
490 	{
491 	    ga_init2(&ga, (int)sizeof(char), 80);
492 	    if (tv.vval.v_list != NULL)
493 	    {
494 		list_join(&ga, tv.vval.v_list, (char_u *)"\n", TRUE, FALSE, 0);
495 		if (tv.vval.v_list->lv_len > 0)
496 		    ga_append(&ga, NL);
497 	    }
498 	    ga_append(&ga, NUL);
499 	    retval = (char_u *)ga.ga_data;
500 	}
501 #ifdef FEAT_FLOAT
502 	else if (convert && tv.v_type == VAR_FLOAT)
503 	{
504 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv.vval.v_float);
505 	    retval = vim_strsave(numbuf);
506 	}
507 #endif
508 	else
509 	    retval = vim_strsave(tv_get_string(&tv));
510 	clear_tv(&tv);
511     }
512     clear_evalarg(&EVALARG_EVALUATE, NULL);
513 
514     return retval;
515 }
516 
517 /*
518  * Call eval_to_string() without using current local variables and using
519  * textwinlock.  When "use_sandbox" is TRUE use the sandbox.
520  */
521     char_u *
522 eval_to_string_safe(
523     char_u	*arg,
524     int		use_sandbox)
525 {
526     char_u	*retval;
527     funccal_entry_T funccal_entry;
528 
529     save_funccal(&funccal_entry);
530     if (use_sandbox)
531 	++sandbox;
532     ++textwinlock;
533     retval = eval_to_string(arg, FALSE);
534     if (use_sandbox)
535 	--sandbox;
536     --textwinlock;
537     restore_funccal();
538     return retval;
539 }
540 
541 /*
542  * Top level evaluation function, returning a number.
543  * Evaluates "expr" silently.
544  * Returns -1 for an error.
545  */
546     varnumber_T
547 eval_to_number(char_u *expr)
548 {
549     typval_T	rettv;
550     varnumber_T	retval;
551     char_u	*p = skipwhite(expr);
552 
553     ++emsg_off;
554 
555     if (eval1(&p, &rettv, &EVALARG_EVALUATE) == FAIL)
556 	retval = -1;
557     else
558     {
559 	retval = tv_get_number_chk(&rettv, NULL);
560 	clear_tv(&rettv);
561     }
562     --emsg_off;
563 
564     return retval;
565 }
566 
567 /*
568  * Top level evaluation function.
569  * Returns an allocated typval_T with the result.
570  * Returns NULL when there is an error.
571  */
572     typval_T *
573 eval_expr(char_u *arg, exarg_T *eap)
574 {
575     typval_T	*tv;
576     evalarg_T	evalarg;
577 
578     fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);
579 
580     tv = ALLOC_ONE(typval_T);
581     if (tv != NULL && eval0(arg, tv, eap, &evalarg) == FAIL)
582 	VIM_CLEAR(tv);
583 
584     clear_evalarg(&evalarg, eap);
585     return tv;
586 }
587 
588 /*
589  * Call some Vim script function and return the result in "*rettv".
590  * Uses argv[0] to argv[argc - 1] for the function arguments.  argv[argc]
591  * should have type VAR_UNKNOWN.
592  * Returns OK or FAIL.
593  */
594     int
595 call_vim_function(
596     char_u      *func,
597     int		argc,
598     typval_T	*argv,
599     typval_T	*rettv)
600 {
601     int		ret;
602     funcexe_T	funcexe;
603 
604     rettv->v_type = VAR_UNKNOWN;		// clear_tv() uses this
605     CLEAR_FIELD(funcexe);
606     funcexe.firstline = curwin->w_cursor.lnum;
607     funcexe.lastline = curwin->w_cursor.lnum;
608     funcexe.evaluate = TRUE;
609     ret = call_func(func, -1, rettv, argc, argv, &funcexe);
610     if (ret == FAIL)
611 	clear_tv(rettv);
612 
613     return ret;
614 }
615 
616 /*
617  * Call Vim script function "func" and return the result as a number.
618  * Returns -1 when calling the function fails.
619  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
620  * have type VAR_UNKNOWN.
621  */
622     varnumber_T
623 call_func_retnr(
624     char_u      *func,
625     int		argc,
626     typval_T	*argv)
627 {
628     typval_T	rettv;
629     varnumber_T	retval;
630 
631     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
632 	return -1;
633 
634     retval = tv_get_number_chk(&rettv, NULL);
635     clear_tv(&rettv);
636     return retval;
637 }
638 
639 /*
640  * Call Vim script function "func" and return the result as a string.
641  * Returns NULL when calling the function fails.
642  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
643  * have type VAR_UNKNOWN.
644  */
645     void *
646 call_func_retstr(
647     char_u      *func,
648     int		argc,
649     typval_T	*argv)
650 {
651     typval_T	rettv;
652     char_u	*retval;
653 
654     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
655 	return NULL;
656 
657     retval = vim_strsave(tv_get_string(&rettv));
658     clear_tv(&rettv);
659     return retval;
660 }
661 
662 /*
663  * Call Vim script function "func" and return the result as a List.
664  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
665  * have type VAR_UNKNOWN.
666  * Returns NULL when there is something wrong.
667  */
668     void *
669 call_func_retlist(
670     char_u      *func,
671     int		argc,
672     typval_T	*argv)
673 {
674     typval_T	rettv;
675 
676     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
677 	return NULL;
678 
679     if (rettv.v_type != VAR_LIST)
680     {
681 	clear_tv(&rettv);
682 	return NULL;
683     }
684 
685     return rettv.vval.v_list;
686 }
687 
688 #ifdef FEAT_FOLDING
689 /*
690  * Evaluate 'foldexpr'.  Returns the foldlevel, and any character preceding
691  * it in "*cp".  Doesn't give error messages.
692  */
693     int
694 eval_foldexpr(char_u *arg, int *cp)
695 {
696     typval_T	tv;
697     varnumber_T	retval;
698     char_u	*s;
699     int		use_sandbox = was_set_insecurely((char_u *)"foldexpr",
700 								   OPT_LOCAL);
701 
702     ++emsg_off;
703     if (use_sandbox)
704 	++sandbox;
705     ++textwinlock;
706     *cp = NUL;
707     if (eval0(arg, &tv, NULL, &EVALARG_EVALUATE) == FAIL)
708 	retval = 0;
709     else
710     {
711 	// If the result is a number, just return the number.
712 	if (tv.v_type == VAR_NUMBER)
713 	    retval = tv.vval.v_number;
714 	else if (tv.v_type != VAR_STRING || tv.vval.v_string == NULL)
715 	    retval = 0;
716 	else
717 	{
718 	    // If the result is a string, check if there is a non-digit before
719 	    // the number.
720 	    s = tv.vval.v_string;
721 	    if (!VIM_ISDIGIT(*s) && *s != '-')
722 		*cp = *s++;
723 	    retval = atol((char *)s);
724 	}
725 	clear_tv(&tv);
726     }
727     --emsg_off;
728     if (use_sandbox)
729 	--sandbox;
730     --textwinlock;
731     clear_evalarg(&EVALARG_EVALUATE, NULL);
732 
733     return (int)retval;
734 }
735 #endif
736 
737 /*
738  * Get an lval: variable, Dict item or List item that can be assigned a value
739  * to: "name", "na{me}", "name[expr]", "name[expr:expr]", "name[expr][expr]",
740  * "name.key", "name.key[expr]" etc.
741  * Indexing only works if "name" is an existing List or Dictionary.
742  * "name" points to the start of the name.
743  * If "rettv" is not NULL it points to the value to be assigned.
744  * "unlet" is TRUE for ":unlet": slightly different behavior when something is
745  * wrong; must end in space or cmd separator.
746  *
747  * flags:
748  *  GLV_QUIET:       do not give error messages
749  *  GLV_READ_ONLY:   will not change the variable
750  *  GLV_NO_AUTOLOAD: do not use script autoloading
751  *
752  * Returns a pointer to just after the name, including indexes.
753  * When an evaluation error occurs "lp->ll_name" is NULL;
754  * Returns NULL for a parsing error.  Still need to free items in "lp"!
755  */
756     char_u *
757 get_lval(
758     char_u	*name,
759     typval_T	*rettv,
760     lval_T	*lp,
761     int		unlet,
762     int		skip,
763     int		flags,	    // GLV_ values
764     int		fne_flags)  // flags for find_name_end()
765 {
766     char_u	*p;
767     char_u	*expr_start, *expr_end;
768     int		cc;
769     dictitem_T	*v;
770     typval_T	var1;
771     typval_T	var2;
772     int		empty1 = FALSE;
773     listitem_T	*ni;
774     char_u	*key = NULL;
775     int		len;
776     hashtab_T	*ht;
777     int		quiet = flags & GLV_QUIET;
778 
779     // Clear everything in "lp".
780     CLEAR_POINTER(lp);
781 
782     if (skip)
783     {
784 	// When skipping just find the end of the name.
785 	lp->ll_name = name;
786 	lp->ll_name_end = find_name_end(name, NULL, NULL,
787 						      FNE_INCL_BR | fne_flags);
788 	return lp->ll_name_end;
789     }
790 
791     // Find the end of the name.
792     p = find_name_end(name, &expr_start, &expr_end, fne_flags);
793     lp->ll_name_end = p;
794     if (expr_start != NULL)
795     {
796 	// Don't expand the name when we already know there is an error.
797 	if (unlet && !VIM_ISWHITE(*p) && !ends_excmd(*p)
798 						    && *p != '[' && *p != '.')
799 	{
800 	    semsg(_(e_trailing_arg), p);
801 	    return NULL;
802 	}
803 
804 	lp->ll_exp_name = make_expanded_name(name, expr_start, expr_end, p);
805 	if (lp->ll_exp_name == NULL)
806 	{
807 	    // Report an invalid expression in braces, unless the
808 	    // expression evaluation has been cancelled due to an
809 	    // aborting error, an interrupt, or an exception.
810 	    if (!aborting() && !quiet)
811 	    {
812 		emsg_severe = TRUE;
813 		semsg(_(e_invarg2), name);
814 		return NULL;
815 	    }
816 	}
817 	lp->ll_name = lp->ll_exp_name;
818     }
819     else
820     {
821 	lp->ll_name = name;
822 
823 	if (in_vim9script())
824 	{
825 	    // "a: type" is declaring variable "a" with a type, not "a:".
826 	    if (p == name + 2 && p[-1] == ':')
827 	    {
828 		--p;
829 		lp->ll_name_end = p;
830 	    }
831 	    if (*p == ':')
832 	    {
833 		scriptitem_T *si = SCRIPT_ITEM(current_sctx.sc_sid);
834 		char_u	 *tp = skipwhite(p + 1);
835 
836 		// parse the type after the name
837 		lp->ll_type = parse_type(&tp, &si->sn_type_list);
838 		lp->ll_name_end = tp;
839 	    }
840 	}
841     }
842 
843     // Without [idx] or .key we are done.
844     if ((*p != '[' && *p != '.') || lp->ll_name == NULL)
845 	return p;
846 
847     cc = *p;
848     *p = NUL;
849     // Only pass &ht when we would write to the variable, it prevents autoload
850     // as well.
851     v = find_var(lp->ll_name, (flags & GLV_READ_ONLY) ? NULL : &ht,
852 						      flags & GLV_NO_AUTOLOAD);
853     if (v == NULL && !quiet)
854 	semsg(_(e_undefvar), lp->ll_name);
855     *p = cc;
856     if (v == NULL)
857 	return NULL;
858 
859     /*
860      * Loop until no more [idx] or .key is following.
861      */
862     lp->ll_tv = &v->di_tv;
863     var1.v_type = VAR_UNKNOWN;
864     var2.v_type = VAR_UNKNOWN;
865     while (*p == '[' || (*p == '.' && lp->ll_tv->v_type == VAR_DICT))
866     {
867 	if (!(lp->ll_tv->v_type == VAR_LIST && lp->ll_tv->vval.v_list != NULL)
868 		&& !(lp->ll_tv->v_type == VAR_DICT
869 					   && lp->ll_tv->vval.v_dict != NULL)
870 		&& !(lp->ll_tv->v_type == VAR_BLOB
871 					   && lp->ll_tv->vval.v_blob != NULL))
872 	{
873 	    if (!quiet)
874 		emsg(_("E689: Can only index a List, Dictionary or Blob"));
875 	    return NULL;
876 	}
877 	if (lp->ll_range)
878 	{
879 	    if (!quiet)
880 		emsg(_("E708: [:] must come last"));
881 	    return NULL;
882 	}
883 
884 	len = -1;
885 	if (*p == '.')
886 	{
887 	    key = p + 1;
888 	    for (len = 0; ASCII_ISALNUM(key[len]) || key[len] == '_'; ++len)
889 		;
890 	    if (len == 0)
891 	    {
892 		if (!quiet)
893 		    emsg(_(e_emptykey));
894 		return NULL;
895 	    }
896 	    p = key + len;
897 	}
898 	else
899 	{
900 	    // Get the index [expr] or the first index [expr: ].
901 	    p = skipwhite(p + 1);
902 	    if (*p == ':')
903 		empty1 = TRUE;
904 	    else
905 	    {
906 		empty1 = FALSE;
907 		if (eval1(&p, &var1, &EVALARG_EVALUATE) == FAIL)  // recursive!
908 		    return NULL;
909 		if (tv_get_string_chk(&var1) == NULL)
910 		{
911 		    // not a number or string
912 		    clear_tv(&var1);
913 		    return NULL;
914 		}
915 		p = skipwhite(p);
916 	    }
917 
918 	    // Optionally get the second index [ :expr].
919 	    if (*p == ':')
920 	    {
921 		if (lp->ll_tv->v_type == VAR_DICT)
922 		{
923 		    if (!quiet)
924 			emsg(_(e_dictrange));
925 		    clear_tv(&var1);
926 		    return NULL;
927 		}
928 		if (rettv != NULL
929 			&& !(rettv->v_type == VAR_LIST
930 						 && rettv->vval.v_list != NULL)
931 			&& !(rettv->v_type == VAR_BLOB
932 						&& rettv->vval.v_blob != NULL))
933 		{
934 		    if (!quiet)
935 			emsg(_("E709: [:] requires a List or Blob value"));
936 		    clear_tv(&var1);
937 		    return NULL;
938 		}
939 		p = skipwhite(p + 1);
940 		if (*p == ']')
941 		    lp->ll_empty2 = TRUE;
942 		else
943 		{
944 		    lp->ll_empty2 = FALSE;
945 		    // recursive!
946 		    if (eval1(&p, &var2, &EVALARG_EVALUATE) == FAIL)
947 		    {
948 			clear_tv(&var1);
949 			return NULL;
950 		    }
951 		    if (tv_get_string_chk(&var2) == NULL)
952 		    {
953 			// not a number or string
954 			clear_tv(&var1);
955 			clear_tv(&var2);
956 			return NULL;
957 		    }
958 		}
959 		lp->ll_range = TRUE;
960 	    }
961 	    else
962 		lp->ll_range = FALSE;
963 
964 	    if (*p != ']')
965 	    {
966 		if (!quiet)
967 		    emsg(_(e_missbrac));
968 		clear_tv(&var1);
969 		clear_tv(&var2);
970 		return NULL;
971 	    }
972 
973 	    // Skip to past ']'.
974 	    ++p;
975 	}
976 
977 	if (lp->ll_tv->v_type == VAR_DICT)
978 	{
979 	    if (len == -1)
980 	    {
981 		// "[key]": get key from "var1"
982 		key = tv_get_string_chk(&var1);	// is number or string
983 		if (key == NULL)
984 		{
985 		    clear_tv(&var1);
986 		    return NULL;
987 		}
988 	    }
989 	    lp->ll_list = NULL;
990 	    lp->ll_dict = lp->ll_tv->vval.v_dict;
991 	    lp->ll_di = dict_find(lp->ll_dict, key, len);
992 
993 	    // When assigning to a scope dictionary check that a function and
994 	    // variable name is valid (only variable name unless it is l: or
995 	    // g: dictionary). Disallow overwriting a builtin function.
996 	    if (rettv != NULL && lp->ll_dict->dv_scope != 0)
997 	    {
998 		int prevval;
999 		int wrong;
1000 
1001 		if (len != -1)
1002 		{
1003 		    prevval = key[len];
1004 		    key[len] = NUL;
1005 		}
1006 		else
1007 		    prevval = 0; // avoid compiler warning
1008 		wrong = (lp->ll_dict->dv_scope == VAR_DEF_SCOPE
1009 			       && rettv->v_type == VAR_FUNC
1010 			       && var_check_func_name(key, lp->ll_di == NULL))
1011 			|| !valid_varname(key);
1012 		if (len != -1)
1013 		    key[len] = prevval;
1014 		if (wrong)
1015 		{
1016 		    clear_tv(&var1);
1017 		    return NULL;
1018 		}
1019 	    }
1020 
1021 	    if (lp->ll_di == NULL)
1022 	    {
1023 		// Can't add "v:" or "a:" variable.
1024 		if (lp->ll_dict == get_vimvar_dict()
1025 			 || &lp->ll_dict->dv_hashtab == get_funccal_args_ht())
1026 		{
1027 		    semsg(_(e_illvar), name);
1028 		    clear_tv(&var1);
1029 		    return NULL;
1030 		}
1031 
1032 		// Key does not exist in dict: may need to add it.
1033 		if (*p == '[' || *p == '.' || unlet)
1034 		{
1035 		    if (!quiet)
1036 			semsg(_(e_dictkey), key);
1037 		    clear_tv(&var1);
1038 		    return NULL;
1039 		}
1040 		if (len == -1)
1041 		    lp->ll_newkey = vim_strsave(key);
1042 		else
1043 		    lp->ll_newkey = vim_strnsave(key, len);
1044 		clear_tv(&var1);
1045 		if (lp->ll_newkey == NULL)
1046 		    p = NULL;
1047 		break;
1048 	    }
1049 	    // existing variable, need to check if it can be changed
1050 	    else if ((flags & GLV_READ_ONLY) == 0
1051 			     && var_check_ro(lp->ll_di->di_flags, name, FALSE))
1052 	    {
1053 		clear_tv(&var1);
1054 		return NULL;
1055 	    }
1056 
1057 	    clear_tv(&var1);
1058 	    lp->ll_tv = &lp->ll_di->di_tv;
1059 	}
1060 	else if (lp->ll_tv->v_type == VAR_BLOB)
1061 	{
1062 	    long bloblen = blob_len(lp->ll_tv->vval.v_blob);
1063 
1064 	    /*
1065 	     * Get the number and item for the only or first index of the List.
1066 	     */
1067 	    if (empty1)
1068 		lp->ll_n1 = 0;
1069 	    else
1070 		// is number or string
1071 		lp->ll_n1 = (long)tv_get_number(&var1);
1072 	    clear_tv(&var1);
1073 
1074 	    if (lp->ll_n1 < 0
1075 		    || lp->ll_n1 > bloblen
1076 		    || (lp->ll_range && lp->ll_n1 == bloblen))
1077 	    {
1078 		if (!quiet)
1079 		    semsg(_(e_blobidx), lp->ll_n1);
1080 		clear_tv(&var2);
1081 		return NULL;
1082 	    }
1083 	    if (lp->ll_range && !lp->ll_empty2)
1084 	    {
1085 		lp->ll_n2 = (long)tv_get_number(&var2);
1086 		clear_tv(&var2);
1087 		if (lp->ll_n2 < 0
1088 			|| lp->ll_n2 >= bloblen
1089 			|| lp->ll_n2 < lp->ll_n1)
1090 		{
1091 		    if (!quiet)
1092 			semsg(_(e_blobidx), lp->ll_n2);
1093 		    return NULL;
1094 		}
1095 	    }
1096 	    lp->ll_blob = lp->ll_tv->vval.v_blob;
1097 	    lp->ll_tv = NULL;
1098 	    break;
1099 	}
1100 	else
1101 	{
1102 	    /*
1103 	     * Get the number and item for the only or first index of the List.
1104 	     */
1105 	    if (empty1)
1106 		lp->ll_n1 = 0;
1107 	    else
1108 		// is number or string
1109 		lp->ll_n1 = (long)tv_get_number(&var1);
1110 	    clear_tv(&var1);
1111 
1112 	    lp->ll_dict = NULL;
1113 	    lp->ll_list = lp->ll_tv->vval.v_list;
1114 	    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
1115 	    if (lp->ll_li == NULL)
1116 	    {
1117 		if (lp->ll_n1 < 0)
1118 		{
1119 		    lp->ll_n1 = 0;
1120 		    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
1121 		}
1122 	    }
1123 	    if (lp->ll_li == NULL)
1124 	    {
1125 		clear_tv(&var2);
1126 		if (!quiet)
1127 		    semsg(_(e_listidx), lp->ll_n1);
1128 		return NULL;
1129 	    }
1130 
1131 	    /*
1132 	     * May need to find the item or absolute index for the second
1133 	     * index of a range.
1134 	     * When no index given: "lp->ll_empty2" is TRUE.
1135 	     * Otherwise "lp->ll_n2" is set to the second index.
1136 	     */
1137 	    if (lp->ll_range && !lp->ll_empty2)
1138 	    {
1139 		lp->ll_n2 = (long)tv_get_number(&var2);
1140 						    // is number or string
1141 		clear_tv(&var2);
1142 		if (lp->ll_n2 < 0)
1143 		{
1144 		    ni = list_find(lp->ll_list, lp->ll_n2);
1145 		    if (ni == NULL)
1146 		    {
1147 			if (!quiet)
1148 			    semsg(_(e_listidx), lp->ll_n2);
1149 			return NULL;
1150 		    }
1151 		    lp->ll_n2 = list_idx_of_item(lp->ll_list, ni);
1152 		}
1153 
1154 		// Check that lp->ll_n2 isn't before lp->ll_n1.
1155 		if (lp->ll_n1 < 0)
1156 		    lp->ll_n1 = list_idx_of_item(lp->ll_list, lp->ll_li);
1157 		if (lp->ll_n2 < lp->ll_n1)
1158 		{
1159 		    if (!quiet)
1160 			semsg(_(e_listidx), lp->ll_n2);
1161 		    return NULL;
1162 		}
1163 	    }
1164 
1165 	    lp->ll_tv = &lp->ll_li->li_tv;
1166 	}
1167     }
1168 
1169     clear_tv(&var1);
1170     lp->ll_name_end = p;
1171     return p;
1172 }
1173 
1174 /*
1175  * Clear lval "lp" that was filled by get_lval().
1176  */
1177     void
1178 clear_lval(lval_T *lp)
1179 {
1180     vim_free(lp->ll_exp_name);
1181     vim_free(lp->ll_newkey);
1182 }
1183 
1184 /*
1185  * Set a variable that was parsed by get_lval() to "rettv".
1186  * "endp" points to just after the parsed name.
1187  * "op" is NULL, "+" for "+=", "-" for "-=", "*" for "*=", "/" for "/=",
1188  * "%" for "%=", "." for ".=" or "=" for "=".
1189  */
1190     void
1191 set_var_lval(
1192     lval_T	*lp,
1193     char_u	*endp,
1194     typval_T	*rettv,
1195     int		copy,
1196     int		flags,    // LET_IS_CONST and/or LET_NO_COMMAND
1197     char_u	*op)
1198 {
1199     int		cc;
1200     listitem_T	*ri;
1201     dictitem_T	*di;
1202 
1203     if (lp->ll_tv == NULL)
1204     {
1205 	cc = *endp;
1206 	*endp = NUL;
1207 	if (lp->ll_blob != NULL)
1208 	{
1209 	    int	    error = FALSE, val;
1210 
1211 	    if (op != NULL && *op != '=')
1212 	    {
1213 		semsg(_(e_letwrong), op);
1214 		return;
1215 	    }
1216 
1217 	    if (lp->ll_range && rettv->v_type == VAR_BLOB)
1218 	    {
1219 		int	il, ir;
1220 
1221 		if (lp->ll_empty2)
1222 		    lp->ll_n2 = blob_len(lp->ll_blob) - 1;
1223 
1224 		if (lp->ll_n2 - lp->ll_n1 + 1 != blob_len(rettv->vval.v_blob))
1225 		{
1226 		    emsg(_("E972: Blob value does not have the right number of bytes"));
1227 		    return;
1228 		}
1229 		if (lp->ll_empty2)
1230 		    lp->ll_n2 = blob_len(lp->ll_blob);
1231 
1232 		ir = 0;
1233 		for (il = lp->ll_n1; il <= lp->ll_n2; il++)
1234 		    blob_set(lp->ll_blob, il,
1235 			    blob_get(rettv->vval.v_blob, ir++));
1236 	    }
1237 	    else
1238 	    {
1239 		val = (int)tv_get_number_chk(rettv, &error);
1240 		if (!error)
1241 		{
1242 		    garray_T *gap = &lp->ll_blob->bv_ga;
1243 
1244 		    // Allow for appending a byte.  Setting a byte beyond
1245 		    // the end is an error otherwise.
1246 		    if (lp->ll_n1 < gap->ga_len
1247 			    || (lp->ll_n1 == gap->ga_len
1248 				&& ga_grow(&lp->ll_blob->bv_ga, 1) == OK))
1249 		    {
1250 			blob_set(lp->ll_blob, lp->ll_n1, val);
1251 			if (lp->ll_n1 == gap->ga_len)
1252 			    ++gap->ga_len;
1253 		    }
1254 		    // error for invalid range was already given in get_lval()
1255 		}
1256 	    }
1257 	}
1258 	else if (op != NULL && *op != '=')
1259 	{
1260 	    typval_T tv;
1261 
1262 	    if (flags & LET_IS_CONST)
1263 	    {
1264 		emsg(_(e_cannot_mod));
1265 		*endp = cc;
1266 		return;
1267 	    }
1268 
1269 	    // handle +=, -=, *=, /=, %= and .=
1270 	    di = NULL;
1271 	    if (eval_variable(lp->ll_name, (int)STRLEN(lp->ll_name),
1272 					     &tv, &di, TRUE, FALSE) == OK)
1273 	    {
1274 		if ((di == NULL
1275 			 || (!var_check_ro(di->di_flags, lp->ll_name, FALSE)
1276 			   && !tv_check_lock(&di->di_tv, lp->ll_name, FALSE)))
1277 			&& tv_op(&tv, rettv, op) == OK)
1278 		    set_var(lp->ll_name, &tv, FALSE);
1279 		clear_tv(&tv);
1280 	    }
1281 	}
1282 	else
1283 	{
1284 	    if (lp->ll_type != NULL
1285 			      && check_typval_type(lp->ll_type, rettv) == FAIL)
1286 		return;
1287 	    set_var_const(lp->ll_name, lp->ll_type, rettv, copy, flags);
1288 	}
1289 	*endp = cc;
1290     }
1291     else if (var_check_lock(lp->ll_newkey == NULL
1292 		? lp->ll_tv->v_lock
1293 		: lp->ll_tv->vval.v_dict->dv_lock, lp->ll_name, FALSE))
1294 	;
1295     else if (lp->ll_range)
1296     {
1297 	listitem_T *ll_li = lp->ll_li;
1298 	int	    ll_n1 = lp->ll_n1;
1299 
1300 	if (flags & LET_IS_CONST)
1301 	{
1302 	    emsg(_("E996: Cannot lock a range"));
1303 	    return;
1304 	}
1305 
1306 	/*
1307 	 * Check whether any of the list items is locked
1308 	 */
1309 	for (ri = rettv->vval.v_list->lv_first; ri != NULL && ll_li != NULL; )
1310 	{
1311 	    if (var_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
1312 		return;
1313 	    ri = ri->li_next;
1314 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == ll_n1))
1315 		break;
1316 	    ll_li = ll_li->li_next;
1317 	    ++ll_n1;
1318 	}
1319 
1320 	/*
1321 	 * Assign the List values to the list items.
1322 	 */
1323 	for (ri = rettv->vval.v_list->lv_first; ri != NULL; )
1324 	{
1325 	    if (op != NULL && *op != '=')
1326 		tv_op(&lp->ll_li->li_tv, &ri->li_tv, op);
1327 	    else
1328 	    {
1329 		clear_tv(&lp->ll_li->li_tv);
1330 		copy_tv(&ri->li_tv, &lp->ll_li->li_tv);
1331 	    }
1332 	    ri = ri->li_next;
1333 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == lp->ll_n1))
1334 		break;
1335 	    if (lp->ll_li->li_next == NULL)
1336 	    {
1337 		// Need to add an empty item.
1338 		if (list_append_number(lp->ll_list, 0) == FAIL)
1339 		{
1340 		    ri = NULL;
1341 		    break;
1342 		}
1343 	    }
1344 	    lp->ll_li = lp->ll_li->li_next;
1345 	    ++lp->ll_n1;
1346 	}
1347 	if (ri != NULL)
1348 	    emsg(_("E710: List value has more items than target"));
1349 	else if (lp->ll_empty2
1350 		? (lp->ll_li != NULL && lp->ll_li->li_next != NULL)
1351 		: lp->ll_n1 != lp->ll_n2)
1352 	    emsg(_("E711: List value has not enough items"));
1353     }
1354     else
1355     {
1356 	/*
1357 	 * Assign to a List or Dictionary item.
1358 	 */
1359 	if (flags & LET_IS_CONST)
1360 	{
1361 	    emsg(_("E996: Cannot lock a list or dict"));
1362 	    return;
1363 	}
1364 	if (lp->ll_newkey != NULL)
1365 	{
1366 	    if (op != NULL && *op != '=')
1367 	    {
1368 		semsg(_(e_letwrong), op);
1369 		return;
1370 	    }
1371 
1372 	    // Need to add an item to the Dictionary.
1373 	    di = dictitem_alloc(lp->ll_newkey);
1374 	    if (di == NULL)
1375 		return;
1376 	    if (dict_add(lp->ll_tv->vval.v_dict, di) == FAIL)
1377 	    {
1378 		vim_free(di);
1379 		return;
1380 	    }
1381 	    lp->ll_tv = &di->di_tv;
1382 	}
1383 	else if (op != NULL && *op != '=')
1384 	{
1385 	    tv_op(lp->ll_tv, rettv, op);
1386 	    return;
1387 	}
1388 	else
1389 	    clear_tv(lp->ll_tv);
1390 
1391 	/*
1392 	 * Assign the value to the variable or list item.
1393 	 */
1394 	if (copy)
1395 	    copy_tv(rettv, lp->ll_tv);
1396 	else
1397 	{
1398 	    *lp->ll_tv = *rettv;
1399 	    lp->ll_tv->v_lock = 0;
1400 	    init_tv(rettv);
1401 	}
1402     }
1403 }
1404 
1405 /*
1406  * Handle "tv1 += tv2", "tv1 -= tv2", "tv1 *= tv2", "tv1 /= tv2", "tv1 %= tv2"
1407  * and "tv1 .= tv2"
1408  * Returns OK or FAIL.
1409  */
1410     static int
1411 tv_op(typval_T *tv1, typval_T *tv2, char_u *op)
1412 {
1413     varnumber_T	n;
1414     char_u	numbuf[NUMBUFLEN];
1415     char_u	*s;
1416 
1417     // Can't do anything with a Funcref, Dict, v:true on the right.
1418     if (tv2->v_type != VAR_FUNC && tv2->v_type != VAR_DICT
1419 		      && tv2->v_type != VAR_BOOL && tv2->v_type != VAR_SPECIAL)
1420     {
1421 	switch (tv1->v_type)
1422 	{
1423 	    case VAR_UNKNOWN:
1424 	    case VAR_ANY:
1425 	    case VAR_VOID:
1426 	    case VAR_DICT:
1427 	    case VAR_FUNC:
1428 	    case VAR_PARTIAL:
1429 	    case VAR_BOOL:
1430 	    case VAR_SPECIAL:
1431 	    case VAR_JOB:
1432 	    case VAR_CHANNEL:
1433 		break;
1434 
1435 	    case VAR_BLOB:
1436 		if (*op != '+' || tv2->v_type != VAR_BLOB)
1437 		    break;
1438 		// BLOB += BLOB
1439 		if (tv1->vval.v_blob != NULL && tv2->vval.v_blob != NULL)
1440 		{
1441 		    blob_T  *b1 = tv1->vval.v_blob;
1442 		    blob_T  *b2 = tv2->vval.v_blob;
1443 		    int	i, len = blob_len(b2);
1444 		    for (i = 0; i < len; i++)
1445 			ga_append(&b1->bv_ga, blob_get(b2, i));
1446 		}
1447 		return OK;
1448 
1449 	    case VAR_LIST:
1450 		if (*op != '+' || tv2->v_type != VAR_LIST)
1451 		    break;
1452 		// List += List
1453 		if (tv1->vval.v_list != NULL && tv2->vval.v_list != NULL)
1454 		    list_extend(tv1->vval.v_list, tv2->vval.v_list, NULL);
1455 		return OK;
1456 
1457 	    case VAR_NUMBER:
1458 	    case VAR_STRING:
1459 		if (tv2->v_type == VAR_LIST)
1460 		    break;
1461 		if (vim_strchr((char_u *)"+-*/%", *op) != NULL)
1462 		{
1463 		    // nr += nr , nr -= nr , nr *=nr , nr /= nr , nr %= nr
1464 		    n = tv_get_number(tv1);
1465 #ifdef FEAT_FLOAT
1466 		    if (tv2->v_type == VAR_FLOAT)
1467 		    {
1468 			float_T f = n;
1469 
1470 			if (*op == '%')
1471 			    break;
1472 			switch (*op)
1473 			{
1474 			    case '+': f += tv2->vval.v_float; break;
1475 			    case '-': f -= tv2->vval.v_float; break;
1476 			    case '*': f *= tv2->vval.v_float; break;
1477 			    case '/': f /= tv2->vval.v_float; break;
1478 			}
1479 			clear_tv(tv1);
1480 			tv1->v_type = VAR_FLOAT;
1481 			tv1->vval.v_float = f;
1482 		    }
1483 		    else
1484 #endif
1485 		    {
1486 			switch (*op)
1487 			{
1488 			    case '+': n += tv_get_number(tv2); break;
1489 			    case '-': n -= tv_get_number(tv2); break;
1490 			    case '*': n *= tv_get_number(tv2); break;
1491 			    case '/': n = num_divide(n, tv_get_number(tv2)); break;
1492 			    case '%': n = num_modulus(n, tv_get_number(tv2)); break;
1493 			}
1494 			clear_tv(tv1);
1495 			tv1->v_type = VAR_NUMBER;
1496 			tv1->vval.v_number = n;
1497 		    }
1498 		}
1499 		else
1500 		{
1501 		    if (tv2->v_type == VAR_FLOAT)
1502 			break;
1503 
1504 		    // str .= str
1505 		    s = tv_get_string(tv1);
1506 		    s = concat_str(s, tv_get_string_buf(tv2, numbuf));
1507 		    clear_tv(tv1);
1508 		    tv1->v_type = VAR_STRING;
1509 		    tv1->vval.v_string = s;
1510 		}
1511 		return OK;
1512 
1513 	    case VAR_FLOAT:
1514 #ifdef FEAT_FLOAT
1515 		{
1516 		    float_T f;
1517 
1518 		    if (*op == '%' || *op == '.'
1519 				   || (tv2->v_type != VAR_FLOAT
1520 				    && tv2->v_type != VAR_NUMBER
1521 				    && tv2->v_type != VAR_STRING))
1522 			break;
1523 		    if (tv2->v_type == VAR_FLOAT)
1524 			f = tv2->vval.v_float;
1525 		    else
1526 			f = tv_get_number(tv2);
1527 		    switch (*op)
1528 		    {
1529 			case '+': tv1->vval.v_float += f; break;
1530 			case '-': tv1->vval.v_float -= f; break;
1531 			case '*': tv1->vval.v_float *= f; break;
1532 			case '/': tv1->vval.v_float /= f; break;
1533 		    }
1534 		}
1535 #endif
1536 		return OK;
1537 	}
1538     }
1539 
1540     semsg(_(e_letwrong), op);
1541     return FAIL;
1542 }
1543 
1544 /*
1545  * Evaluate the expression used in a ":for var in expr" command.
1546  * "arg" points to "var".
1547  * Set "*errp" to TRUE for an error, FALSE otherwise;
1548  * Return a pointer that holds the info.  Null when there is an error.
1549  */
1550     void *
1551 eval_for_line(
1552     char_u	*arg,
1553     int		*errp,
1554     exarg_T	*eap,
1555     evalarg_T	*evalarg)
1556 {
1557     forinfo_T	*fi;
1558     char_u	*expr;
1559     typval_T	tv;
1560     list_T	*l;
1561     int		skip = !(evalarg->eval_flags & EVAL_EVALUATE);
1562 
1563     *errp = TRUE;	// default: there is an error
1564 
1565     fi = ALLOC_CLEAR_ONE(forinfo_T);
1566     if (fi == NULL)
1567 	return NULL;
1568 
1569     expr = skip_var_list(arg, TRUE, &fi->fi_varcount, &fi->fi_semicolon, FALSE);
1570     if (expr == NULL)
1571 	return fi;
1572 
1573     expr = skipwhite_and_linebreak(expr, evalarg);
1574     if (expr[0] != 'i' || expr[1] != 'n'
1575 				  || !(expr[2] == NUL || VIM_ISWHITE(expr[2])))
1576     {
1577 	emsg(_(e_missing_in));
1578 	return fi;
1579     }
1580 
1581     if (skip)
1582 	++emsg_skip;
1583     expr = skipwhite_and_linebreak(expr + 2, evalarg);
1584     if (eval0(expr, &tv, eap, evalarg) == OK)
1585     {
1586 	*errp = FALSE;
1587 	if (!skip)
1588 	{
1589 	    if (tv.v_type == VAR_LIST)
1590 	    {
1591 		l = tv.vval.v_list;
1592 		if (l == NULL)
1593 		{
1594 		    // a null list is like an empty list: do nothing
1595 		    clear_tv(&tv);
1596 		}
1597 		else
1598 		{
1599 		    // Need a real list here.
1600 		    CHECK_LIST_MATERIALIZE(l);
1601 
1602 		    // No need to increment the refcount, it's already set for
1603 		    // the list being used in "tv".
1604 		    fi->fi_list = l;
1605 		    list_add_watch(l, &fi->fi_lw);
1606 		    fi->fi_lw.lw_item = l->lv_first;
1607 		}
1608 	    }
1609 	    else if (tv.v_type == VAR_BLOB)
1610 	    {
1611 		fi->fi_bi = 0;
1612 		if (tv.vval.v_blob != NULL)
1613 		{
1614 		    typval_T btv;
1615 
1616 		    // Make a copy, so that the iteration still works when the
1617 		    // blob is changed.
1618 		    blob_copy(tv.vval.v_blob, &btv);
1619 		    fi->fi_blob = btv.vval.v_blob;
1620 		}
1621 		clear_tv(&tv);
1622 	    }
1623 	    else
1624 	    {
1625 		emsg(_(e_listreq));
1626 		clear_tv(&tv);
1627 	    }
1628 	}
1629     }
1630     if (skip)
1631 	--emsg_skip;
1632     fi->fi_break_count = evalarg->eval_break_count;
1633 
1634     return fi;
1635 }
1636 
1637 /*
1638  * Used when looping over a :for line, skip the "in expr" part.
1639  */
1640     void
1641 skip_for_lines(void *fi_void, evalarg_T *evalarg)
1642 {
1643     forinfo_T	*fi = (forinfo_T *)fi_void;
1644     int		i;
1645 
1646     for (i = 0; i < fi->fi_break_count; ++i)
1647 	eval_next_line(evalarg);
1648 }
1649 
1650 /*
1651  * Use the first item in a ":for" list.  Advance to the next.
1652  * Assign the values to the variable (list).  "arg" points to the first one.
1653  * Return TRUE when a valid item was found, FALSE when at end of list or
1654  * something wrong.
1655  */
1656     int
1657 next_for_item(void *fi_void, char_u *arg)
1658 {
1659     forinfo_T	*fi = (forinfo_T *)fi_void;
1660     int		result;
1661     int		flag = in_vim9script() ?  LET_NO_COMMAND : 0;
1662     listitem_T	*item;
1663 
1664     if (fi->fi_blob != NULL)
1665     {
1666 	typval_T	tv;
1667 
1668 	if (fi->fi_bi >= blob_len(fi->fi_blob))
1669 	    return FALSE;
1670 	tv.v_type = VAR_NUMBER;
1671 	tv.v_lock = VAR_FIXED;
1672 	tv.vval.v_number = blob_get(fi->fi_blob, fi->fi_bi);
1673 	++fi->fi_bi;
1674 	return ex_let_vars(arg, &tv, TRUE, fi->fi_semicolon,
1675 				       fi->fi_varcount, flag, NULL) == OK;
1676     }
1677 
1678     item = fi->fi_lw.lw_item;
1679     if (item == NULL)
1680 	result = FALSE;
1681     else
1682     {
1683 	fi->fi_lw.lw_item = item->li_next;
1684 	result = (ex_let_vars(arg, &item->li_tv, TRUE, fi->fi_semicolon,
1685 				      fi->fi_varcount, flag, NULL) == OK);
1686     }
1687     return result;
1688 }
1689 
1690 /*
1691  * Free the structure used to store info used by ":for".
1692  */
1693     void
1694 free_for_info(void *fi_void)
1695 {
1696     forinfo_T    *fi = (forinfo_T *)fi_void;
1697 
1698     if (fi != NULL && fi->fi_list != NULL)
1699     {
1700 	list_rem_watch(fi->fi_list, &fi->fi_lw);
1701 	list_unref(fi->fi_list);
1702     }
1703     if (fi != NULL && fi->fi_blob != NULL)
1704 	blob_unref(fi->fi_blob);
1705     vim_free(fi);
1706 }
1707 
1708     void
1709 set_context_for_expression(
1710     expand_T	*xp,
1711     char_u	*arg,
1712     cmdidx_T	cmdidx)
1713 {
1714     int		got_eq = FALSE;
1715     int		c;
1716     char_u	*p;
1717 
1718     if (cmdidx == CMD_let || cmdidx == CMD_const)
1719     {
1720 	xp->xp_context = EXPAND_USER_VARS;
1721 	if (vim_strpbrk(arg, (char_u *)"\"'+-*/%.=!?~|&$([<>,#") == NULL)
1722 	{
1723 	    // ":let var1 var2 ...": find last space.
1724 	    for (p = arg + STRLEN(arg); p >= arg; )
1725 	    {
1726 		xp->xp_pattern = p;
1727 		MB_PTR_BACK(arg, p);
1728 		if (VIM_ISWHITE(*p))
1729 		    break;
1730 	    }
1731 	    return;
1732 	}
1733     }
1734     else
1735 	xp->xp_context = cmdidx == CMD_call ? EXPAND_FUNCTIONS
1736 							  : EXPAND_EXPRESSION;
1737     while ((xp->xp_pattern = vim_strpbrk(arg,
1738 				  (char_u *)"\"'+-*/%.=!?~|&$([<>,#")) != NULL)
1739     {
1740 	c = *xp->xp_pattern;
1741 	if (c == '&')
1742 	{
1743 	    c = xp->xp_pattern[1];
1744 	    if (c == '&')
1745 	    {
1746 		++xp->xp_pattern;
1747 		xp->xp_context = cmdidx != CMD_let || got_eq
1748 					 ? EXPAND_EXPRESSION : EXPAND_NOTHING;
1749 	    }
1750 	    else if (c != ' ')
1751 	    {
1752 		xp->xp_context = EXPAND_SETTINGS;
1753 		if ((c == 'l' || c == 'g') && xp->xp_pattern[2] == ':')
1754 		    xp->xp_pattern += 2;
1755 
1756 	    }
1757 	}
1758 	else if (c == '$')
1759 	{
1760 	    // environment variable
1761 	    xp->xp_context = EXPAND_ENV_VARS;
1762 	}
1763 	else if (c == '=')
1764 	{
1765 	    got_eq = TRUE;
1766 	    xp->xp_context = EXPAND_EXPRESSION;
1767 	}
1768 	else if (c == '#'
1769 		&& xp->xp_context == EXPAND_EXPRESSION)
1770 	{
1771 	    // Autoload function/variable contains '#'.
1772 	    break;
1773 	}
1774 	else if ((c == '<' || c == '#')
1775 		&& xp->xp_context == EXPAND_FUNCTIONS
1776 		&& vim_strchr(xp->xp_pattern, '(') == NULL)
1777 	{
1778 	    // Function name can start with "<SNR>" and contain '#'.
1779 	    break;
1780 	}
1781 	else if (cmdidx != CMD_let || got_eq)
1782 	{
1783 	    if (c == '"')	    // string
1784 	    {
1785 		while ((c = *++xp->xp_pattern) != NUL && c != '"')
1786 		    if (c == '\\' && xp->xp_pattern[1] != NUL)
1787 			++xp->xp_pattern;
1788 		xp->xp_context = EXPAND_NOTHING;
1789 	    }
1790 	    else if (c == '\'')	    // literal string
1791 	    {
1792 		// Trick: '' is like stopping and starting a literal string.
1793 		while ((c = *++xp->xp_pattern) != NUL && c != '\'')
1794 		    /* skip */ ;
1795 		xp->xp_context = EXPAND_NOTHING;
1796 	    }
1797 	    else if (c == '|')
1798 	    {
1799 		if (xp->xp_pattern[1] == '|')
1800 		{
1801 		    ++xp->xp_pattern;
1802 		    xp->xp_context = EXPAND_EXPRESSION;
1803 		}
1804 		else
1805 		    xp->xp_context = EXPAND_COMMANDS;
1806 	    }
1807 	    else
1808 		xp->xp_context = EXPAND_EXPRESSION;
1809 	}
1810 	else
1811 	    // Doesn't look like something valid, expand as an expression
1812 	    // anyway.
1813 	    xp->xp_context = EXPAND_EXPRESSION;
1814 	arg = xp->xp_pattern;
1815 	if (*arg != NUL)
1816 	    while ((c = *++arg) != NUL && (c == ' ' || c == '\t'))
1817 		/* skip */ ;
1818     }
1819     xp->xp_pattern = arg;
1820 }
1821 
1822 /*
1823  * Return TRUE if "pat" matches "text".
1824  * Does not use 'cpo' and always uses 'magic'.
1825  */
1826     int
1827 pattern_match(char_u *pat, char_u *text, int ic)
1828 {
1829     int		matches = FALSE;
1830     char_u	*save_cpo;
1831     regmatch_T	regmatch;
1832 
1833     // avoid 'l' flag in 'cpoptions'
1834     save_cpo = p_cpo;
1835     p_cpo = (char_u *)"";
1836     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
1837     if (regmatch.regprog != NULL)
1838     {
1839 	regmatch.rm_ic = ic;
1840 	matches = vim_regexec_nl(&regmatch, text, (colnr_T)0);
1841 	vim_regfree(regmatch.regprog);
1842     }
1843     p_cpo = save_cpo;
1844     return matches;
1845 }
1846 
1847 /*
1848  * Handle a name followed by "(".  Both for just "name(arg)" and for
1849  * "expr->name(arg)".
1850  * Returns OK or FAIL.
1851  */
1852     static int
1853 eval_func(
1854 	char_u	    **arg,	// points to "(", will be advanced
1855 	evalarg_T   *evalarg,
1856 	char_u	    *name,
1857 	int	    name_len,
1858 	typval_T    *rettv,
1859 	int	    flags,
1860 	typval_T    *basetv)	// "expr" for "expr->name(arg)"
1861 {
1862     int		evaluate = flags & EVAL_EVALUATE;
1863     char_u	*s = name;
1864     int		len = name_len;
1865     partial_T	*partial;
1866     int		ret = OK;
1867 
1868     if (!evaluate)
1869 	check_vars(s, len);
1870 
1871     // If "s" is the name of a variable of type VAR_FUNC
1872     // use its contents.
1873     s = deref_func_name(s, &len, &partial, !evaluate);
1874 
1875     // Need to make a copy, in case evaluating the arguments makes
1876     // the name invalid.
1877     s = vim_strsave(s);
1878     if (s == NULL || (flags & EVAL_CONSTANT))
1879 	ret = FAIL;
1880     else
1881     {
1882 	funcexe_T funcexe;
1883 
1884 	// Invoke the function.
1885 	CLEAR_FIELD(funcexe);
1886 	funcexe.firstline = curwin->w_cursor.lnum;
1887 	funcexe.lastline = curwin->w_cursor.lnum;
1888 	funcexe.evaluate = evaluate;
1889 	funcexe.partial = partial;
1890 	funcexe.basetv = basetv;
1891 	ret = get_func_tv(s, len, rettv, arg, evalarg, &funcexe);
1892     }
1893     vim_free(s);
1894 
1895     // If evaluate is FALSE rettv->v_type was not set in
1896     // get_func_tv, but it's needed in handle_subscript() to parse
1897     // what follows. So set it here.
1898     if (rettv->v_type == VAR_UNKNOWN && !evaluate && **arg == '(')
1899     {
1900 	rettv->vval.v_string = NULL;
1901 	rettv->v_type = VAR_FUNC;
1902     }
1903 
1904     // Stop the expression evaluation when immediately
1905     // aborting on error, or when an interrupt occurred or
1906     // an exception was thrown but not caught.
1907     if (evaluate && aborting())
1908     {
1909 	if (ret == OK)
1910 	    clear_tv(rettv);
1911 	ret = FAIL;
1912     }
1913     return ret;
1914 }
1915 
1916 /*
1917  * If inside Vim9 script, "arg" points to the end of a line (ignoring a #
1918  * comment) and there is a next line, return the next line (skipping blanks)
1919  * and set "getnext".
1920  * Otherwise just return "arg" unmodified and set "getnext" to FALSE.
1921  * "arg" must point somewhere inside a line, not at the start.
1922  */
1923     char_u *
1924 eval_next_non_blank(char_u *arg, evalarg_T *evalarg, int *getnext)
1925 {
1926     char_u *p = skipwhite(arg);
1927 
1928     *getnext = FALSE;
1929     if (in_vim9script()
1930 	    && evalarg != NULL
1931 	    && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL)
1932 	    && (*p == NUL || (VIM_ISWHITE(p[-1]) && vim9_comment_start(p))))
1933     {
1934 	char_u *next;
1935 
1936 	if (evalarg->eval_cookie != NULL)
1937 	    next = getline_peek(evalarg->eval_getline, evalarg->eval_cookie);
1938 	else
1939 	    next = peek_next_line_from_context(evalarg->eval_cctx);
1940 
1941 	if (next != NULL)
1942 	{
1943 	    *getnext = TRUE;
1944 	    return skipwhite(next);
1945 	}
1946     }
1947     return p;
1948 }
1949 
1950 /*
1951  * To be called after eval_next_non_blank() sets "getnext" to TRUE.
1952  */
1953     char_u *
1954 eval_next_line(evalarg_T *evalarg)
1955 {
1956     garray_T	*gap = &evalarg->eval_ga;
1957     char_u	*line;
1958 
1959     if (evalarg->eval_cookie != NULL)
1960 	line = evalarg->eval_getline(0, evalarg->eval_cookie, 0, TRUE);
1961     else
1962 	line = next_line_from_context(evalarg->eval_cctx, TRUE);
1963     ++evalarg->eval_break_count;
1964     if (gap->ga_itemsize > 0 && ga_grow(gap, 1) == OK)
1965     {
1966 	// Going to concatenate the lines after parsing.
1967 	((char_u **)gap->ga_data)[gap->ga_len] = line;
1968 	++gap->ga_len;
1969     }
1970     else if (evalarg->eval_cookie != NULL)
1971     {
1972 	vim_free(evalarg->eval_tofree);
1973 	evalarg->eval_tofree = line;
1974     }
1975     return skipwhite(line);
1976 }
1977 
1978 /*
1979  * Call eval_next_non_blank() and get the next line if needed.
1980  */
1981     char_u *
1982 skipwhite_and_linebreak(char_u *arg, evalarg_T *evalarg)
1983 {
1984     int	    getnext;
1985     char_u  *p = skipwhite(arg);
1986 
1987     if (evalarg == NULL)
1988 	return skipwhite(arg);
1989     eval_next_non_blank(p, evalarg, &getnext);
1990     if (getnext)
1991 	return eval_next_line(evalarg);
1992     return p;
1993 }
1994 
1995 /*
1996  * After using "evalarg" filled from "eap": free the memory.
1997  */
1998     void
1999 clear_evalarg(evalarg_T *evalarg, exarg_T *eap)
2000 {
2001     if (evalarg != NULL)
2002     {
2003 	if (evalarg->eval_tofree != NULL)
2004 	{
2005 	    if (eap != NULL)
2006 	    {
2007 		// We may need to keep the original command line, e.g. for
2008 		// ":let" it has the variable names.  But we may also need the
2009 		// new one, "nextcmd" points into it.  Keep both.
2010 		vim_free(eap->cmdline_tofree);
2011 		eap->cmdline_tofree = *eap->cmdlinep;
2012 		*eap->cmdlinep = evalarg->eval_tofree;
2013 	    }
2014 	    else
2015 		vim_free(evalarg->eval_tofree);
2016 	    evalarg->eval_tofree = NULL;
2017 	}
2018 
2019 	vim_free(evalarg->eval_tofree_lambda);
2020 	evalarg->eval_tofree_lambda = NULL;
2021     }
2022 }
2023 
2024 /*
2025  * The "evaluate" argument: When FALSE, the argument is only parsed but not
2026  * executed.  The function may return OK, but the rettv will be of type
2027  * VAR_UNKNOWN.  The function still returns FAIL for a syntax error.
2028  */
2029 
2030 /*
2031  * Handle zero level expression.
2032  * This calls eval1() and handles error message and nextcmd.
2033  * Put the result in "rettv" when returning OK and "evaluate" is TRUE.
2034  * Note: "rettv.v_lock" is not set.
2035  * "evalarg" can be NULL, EVALARG_EVALUATE or a pointer.
2036  * Return OK or FAIL.
2037  */
2038     int
2039 eval0(
2040     char_u	*arg,
2041     typval_T	*rettv,
2042     exarg_T	*eap,
2043     evalarg_T	*evalarg)
2044 {
2045     int		ret;
2046     char_u	*p;
2047     int		did_emsg_before = did_emsg;
2048     int		called_emsg_before = called_emsg;
2049     int		flags = evalarg == NULL ? 0 : evalarg->eval_flags;
2050 
2051     p = skipwhite(arg);
2052     ret = eval1(&p, rettv, evalarg);
2053     p = skipwhite(p);
2054 
2055     if (ret == FAIL || !ends_excmd2(arg, p))
2056     {
2057 	if (ret != FAIL)
2058 	    clear_tv(rettv);
2059 	/*
2060 	 * Report the invalid expression unless the expression evaluation has
2061 	 * been cancelled due to an aborting error, an interrupt, or an
2062 	 * exception, or we already gave a more specific error.
2063 	 * Also check called_emsg for when using assert_fails().
2064 	 */
2065 	if (!aborting()
2066 		&& did_emsg == did_emsg_before
2067 		&& called_emsg == called_emsg_before
2068 		&& (flags & EVAL_CONSTANT) == 0)
2069 	    semsg(_(e_invexpr2), arg);
2070 	ret = FAIL;
2071     }
2072 
2073     if (eap != NULL)
2074 	eap->nextcmd = check_nextcmd(p);
2075 
2076     return ret;
2077 }
2078 
2079 /*
2080  * Handle top level expression:
2081  *	expr2 ? expr1 : expr1
2082  *
2083  * "arg" must point to the first non-white of the expression.
2084  * "arg" is advanced to just after the recognized expression.
2085  *
2086  * Note: "rettv.v_lock" is not set.
2087  *
2088  * Return OK or FAIL.
2089  */
2090     int
2091 eval1(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2092 {
2093     char_u  *p;
2094     int	    getnext;
2095 
2096     /*
2097      * Get the first variable.
2098      */
2099     if (eval2(arg, rettv, evalarg) == FAIL)
2100 	return FAIL;
2101 
2102     p = eval_next_non_blank(*arg, evalarg, &getnext);
2103     if (*p == '?')
2104     {
2105 	int		result;
2106 	typval_T	var2;
2107 	evalarg_T	*evalarg_used = evalarg;
2108 	evalarg_T	local_evalarg;
2109 	int		orig_flags;
2110 	int		evaluate;
2111 
2112 	if (evalarg == NULL)
2113 	{
2114 	    CLEAR_FIELD(local_evalarg);
2115 	    evalarg_used = &local_evalarg;
2116 	}
2117 	orig_flags = evalarg_used->eval_flags;
2118 	evaluate = evalarg_used->eval_flags & EVAL_EVALUATE;
2119 
2120 	if (getnext)
2121 	    *arg = eval_next_line(evalarg_used);
2122 	else
2123 	{
2124 	    if (evaluate && in_vim9script() && !VIM_ISWHITE(p[-1]))
2125 	    {
2126 		error_white_both(p, 1);
2127 		clear_tv(rettv);
2128 		return FAIL;
2129 	    }
2130 	    *arg = p;
2131 	}
2132 
2133 	result = FALSE;
2134 	if (evaluate)
2135 	{
2136 	    int		error = FALSE;
2137 
2138 	    if (tv_get_number_chk(rettv, &error) != 0)
2139 		result = TRUE;
2140 	    clear_tv(rettv);
2141 	    if (error)
2142 		return FAIL;
2143 	}
2144 
2145 	/*
2146 	 * Get the second variable.  Recursive!
2147 	 */
2148 	if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[1]))
2149 	{
2150 	    error_white_both(p, 1);
2151 	    clear_tv(rettv);
2152 	    return FAIL;
2153 	}
2154 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg_used);
2155 	evalarg_used->eval_flags = result ? orig_flags
2156 						 : orig_flags & ~EVAL_EVALUATE;
2157 	if (eval1(arg, rettv, evalarg_used) == FAIL)
2158 	    return FAIL;
2159 
2160 	/*
2161 	 * Check for the ":".
2162 	 */
2163 	p = eval_next_non_blank(*arg, evalarg_used, &getnext);
2164 	if (*p != ':')
2165 	{
2166 	    emsg(_(e_missing_colon));
2167 	    if (evaluate && result)
2168 		clear_tv(rettv);
2169 	    return FAIL;
2170 	}
2171 	if (getnext)
2172 	    *arg = eval_next_line(evalarg_used);
2173 	else
2174 	{
2175 	    if (evaluate && in_vim9script() && !VIM_ISWHITE(p[-1]))
2176 	    {
2177 		error_white_both(p, 1);
2178 		clear_tv(rettv);
2179 		return FAIL;
2180 	    }
2181 	    *arg = p;
2182 	}
2183 
2184 	/*
2185 	 * Get the third variable.  Recursive!
2186 	 */
2187 	if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[1]))
2188 	{
2189 	    error_white_both(p, 1);
2190 	    clear_tv(rettv);
2191 	    return FAIL;
2192 	}
2193 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg_used);
2194 	evalarg_used->eval_flags = !result ? orig_flags
2195 						 : orig_flags & ~EVAL_EVALUATE;
2196 	if (eval1(arg, &var2, evalarg_used) == FAIL)
2197 	{
2198 	    if (evaluate && result)
2199 		clear_tv(rettv);
2200 	    return FAIL;
2201 	}
2202 	if (evaluate && !result)
2203 	    *rettv = var2;
2204 
2205 	if (evalarg == NULL)
2206 	    clear_evalarg(&local_evalarg, NULL);
2207 	else
2208 	    evalarg->eval_flags = orig_flags;
2209     }
2210 
2211     return OK;
2212 }
2213 
2214 /*
2215  * Handle first level expression:
2216  *	expr2 || expr2 || expr2	    logical OR
2217  *
2218  * "arg" must point to the first non-white of the expression.
2219  * "arg" is advanced to just after the recognized expression.
2220  *
2221  * Return OK or FAIL.
2222  */
2223     static int
2224 eval2(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2225 {
2226     char_u	*p;
2227     int		getnext;
2228 
2229     /*
2230      * Get the first variable.
2231      */
2232     if (eval3(arg, rettv, evalarg) == FAIL)
2233 	return FAIL;
2234 
2235     /*
2236      * Handle the  "||" operator.
2237      */
2238     p = eval_next_non_blank(*arg, evalarg, &getnext);
2239     if (p[0] == '|' && p[1] == '|')
2240     {
2241 	evalarg_T   *evalarg_used = evalarg;
2242 	evalarg_T   local_evalarg;
2243 	int	    evaluate;
2244 	int	    orig_flags;
2245 	long	    result = FALSE;
2246 	typval_T    var2;
2247 	int	    error;
2248 	int	    vim9script = in_vim9script();
2249 
2250 	if (evalarg == NULL)
2251 	{
2252 	    CLEAR_FIELD(local_evalarg);
2253 	    evalarg_used = &local_evalarg;
2254 	}
2255 	orig_flags = evalarg_used->eval_flags;
2256 	evaluate = orig_flags & EVAL_EVALUATE;
2257 	if (evaluate)
2258 	{
2259 	    if (vim9script)
2260 	    {
2261 		result = tv2bool(rettv);
2262 	    }
2263 	    else
2264 	    {
2265 		error = FALSE;
2266 		if (tv_get_number_chk(rettv, &error) != 0)
2267 		    result = TRUE;
2268 		clear_tv(rettv);
2269 		if (error)
2270 		    return FAIL;
2271 	    }
2272 	}
2273 
2274 	/*
2275 	 * Repeat until there is no following "||".
2276 	 */
2277 	while (p[0] == '|' && p[1] == '|')
2278 	{
2279 	    if (getnext)
2280 		*arg = eval_next_line(evalarg_used);
2281 	    else
2282 	    {
2283 		if (evaluate && in_vim9script() && !VIM_ISWHITE(p[-1]))
2284 		{
2285 		    error_white_both(p, 2);
2286 		    clear_tv(rettv);
2287 		    return FAIL;
2288 		}
2289 		*arg = p;
2290 	    }
2291 
2292 	    /*
2293 	     * Get the second variable.
2294 	     */
2295 	    if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[2]))
2296 	    {
2297 		error_white_both(p, 2);
2298 		clear_tv(rettv);
2299 		return FAIL;
2300 	    }
2301 	    *arg = skipwhite_and_linebreak(*arg + 2, evalarg_used);
2302 	    evalarg_used->eval_flags = !result ? orig_flags
2303 						 : orig_flags & ~EVAL_EVALUATE;
2304 	    if (eval3(arg, &var2, evalarg_used) == FAIL)
2305 		return FAIL;
2306 
2307 	    /*
2308 	     * Compute the result.
2309 	     */
2310 	    if (evaluate && !result)
2311 	    {
2312 		if (vim9script)
2313 		{
2314 		    clear_tv(rettv);
2315 		    *rettv = var2;
2316 		    result = tv2bool(rettv);
2317 		}
2318 		else
2319 		{
2320 		    if (tv_get_number_chk(&var2, &error) != 0)
2321 			result = TRUE;
2322 		    clear_tv(&var2);
2323 		    if (error)
2324 			return FAIL;
2325 		}
2326 	    }
2327 	    if (evaluate && !vim9script)
2328 	    {
2329 		rettv->v_type = VAR_NUMBER;
2330 		rettv->vval.v_number = result;
2331 	    }
2332 
2333 	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
2334 	}
2335 
2336 	if (evalarg == NULL)
2337 	    clear_evalarg(&local_evalarg, NULL);
2338 	else
2339 	    evalarg->eval_flags = orig_flags;
2340     }
2341 
2342     return OK;
2343 }
2344 
2345 /*
2346  * Handle second level expression:
2347  *	expr3 && expr3 && expr3	    logical AND
2348  *
2349  * "arg" must point to the first non-white of the expression.
2350  * "arg" is advanced to just after the recognized expression.
2351  *
2352  * Return OK or FAIL.
2353  */
2354     static int
2355 eval3(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2356 {
2357     char_u	*p;
2358     int		getnext;
2359 
2360     /*
2361      * Get the first variable.
2362      */
2363     if (eval4(arg, rettv, evalarg) == FAIL)
2364 	return FAIL;
2365 
2366     /*
2367      * Handle the "&&" operator.
2368      */
2369     p = eval_next_non_blank(*arg, evalarg, &getnext);
2370     if (p[0] == '&' && p[1] == '&')
2371     {
2372 	evalarg_T   *evalarg_used = evalarg;
2373 	evalarg_T   local_evalarg;
2374 	int	    orig_flags;
2375 	int	    evaluate;
2376 	long	    result = TRUE;
2377 	typval_T    var2;
2378 	int	    error;
2379 	int	    vim9script = in_vim9script();
2380 
2381 	if (evalarg == NULL)
2382 	{
2383 	    CLEAR_FIELD(local_evalarg);
2384 	    evalarg_used = &local_evalarg;
2385 	}
2386 	orig_flags = evalarg_used->eval_flags;
2387 	evaluate = orig_flags & EVAL_EVALUATE;
2388 	if (evaluate)
2389 	{
2390 	    if (vim9script)
2391 	    {
2392 		result = tv2bool(rettv);
2393 	    }
2394 	    else
2395 	    {
2396 		error = FALSE;
2397 		if (tv_get_number_chk(rettv, &error) == 0)
2398 		    result = FALSE;
2399 		clear_tv(rettv);
2400 		if (error)
2401 		    return FAIL;
2402 	    }
2403 	}
2404 
2405 	/*
2406 	 * Repeat until there is no following "&&".
2407 	 */
2408 	while (p[0] == '&' && p[1] == '&')
2409 	{
2410 	    if (getnext)
2411 		*arg = eval_next_line(evalarg_used);
2412 	    else
2413 	    {
2414 		if (evaluate && in_vim9script() && !VIM_ISWHITE(p[-1]))
2415 		{
2416 		    error_white_both(p, 2);
2417 		    clear_tv(rettv);
2418 		    return FAIL;
2419 		}
2420 		*arg = p;
2421 	    }
2422 
2423 	    /*
2424 	     * Get the second variable.
2425 	     */
2426 	    if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[2]))
2427 	    {
2428 		error_white_both(p, 2);
2429 		clear_tv(rettv);
2430 		return FAIL;
2431 	    }
2432 	    *arg = skipwhite_and_linebreak(*arg + 2, evalarg_used);
2433 	    evalarg_used->eval_flags = result ? orig_flags
2434 						 : orig_flags & ~EVAL_EVALUATE;
2435 	    if (eval4(arg, &var2, evalarg_used) == FAIL)
2436 		return FAIL;
2437 
2438 	    /*
2439 	     * Compute the result.
2440 	     */
2441 	    if (evaluate && result)
2442 	    {
2443 		if (vim9script)
2444 		{
2445 		    clear_tv(rettv);
2446 		    *rettv = var2;
2447 		    result = tv2bool(rettv);
2448 		}
2449 		else
2450 		{
2451 		    if (tv_get_number_chk(&var2, &error) == 0)
2452 			result = FALSE;
2453 		    clear_tv(&var2);
2454 		    if (error)
2455 			return FAIL;
2456 		}
2457 	    }
2458 	    if (evaluate && !vim9script)
2459 	    {
2460 		rettv->v_type = VAR_NUMBER;
2461 		rettv->vval.v_number = result;
2462 	    }
2463 
2464 	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
2465 	}
2466 
2467 	if (evalarg == NULL)
2468 	    clear_evalarg(&local_evalarg, NULL);
2469 	else
2470 	    evalarg->eval_flags = orig_flags;
2471     }
2472 
2473     return OK;
2474 }
2475 
2476 /*
2477  * Handle third level expression:
2478  *	var1 == var2
2479  *	var1 =~ var2
2480  *	var1 != var2
2481  *	var1 !~ var2
2482  *	var1 > var2
2483  *	var1 >= var2
2484  *	var1 < var2
2485  *	var1 <= var2
2486  *	var1 is var2
2487  *	var1 isnot var2
2488  *
2489  * "arg" must point to the first non-white of the expression.
2490  * "arg" is advanced to just after the recognized expression.
2491  *
2492  * Return OK or FAIL.
2493  */
2494     static int
2495 eval4(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2496 {
2497     char_u	*p;
2498     int		getnext;
2499     exptype_T	type = EXPR_UNKNOWN;
2500     int		len = 2;
2501     int		type_is = FALSE;
2502 
2503     /*
2504      * Get the first variable.
2505      */
2506     if (eval5(arg, rettv, evalarg) == FAIL)
2507 	return FAIL;
2508 
2509     p = eval_next_non_blank(*arg, evalarg, &getnext);
2510     type = get_compare_type(p, &len, &type_is);
2511 
2512     /*
2513      * If there is a comparative operator, use it.
2514      */
2515     if (type != EXPR_UNKNOWN)
2516     {
2517 	typval_T    var2;
2518 	int	    ic;
2519 	int	    vim9script = in_vim9script();
2520 	int	    evaluate = evalarg == NULL
2521 				   ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
2522 
2523 	if (getnext)
2524 	    *arg = eval_next_line(evalarg);
2525 	else if (evaluate && vim9script && !VIM_ISWHITE(**arg))
2526 	{
2527 	    error_white_both(p, len);
2528 	    clear_tv(rettv);
2529 	    return FAIL;
2530 	}
2531 
2532 	if (vim9script && type_is && (p[len] == '?' || p[len] == '#'))
2533 	{
2534 	    semsg(_(e_invexpr2), p);
2535 	    clear_tv(rettv);
2536 	    return FAIL;
2537 	}
2538 
2539 	// extra question mark appended: ignore case
2540 	if (p[len] == '?')
2541 	{
2542 	    ic = TRUE;
2543 	    ++len;
2544 	}
2545 	// extra '#' appended: match case
2546 	else if (p[len] == '#')
2547 	{
2548 	    ic = FALSE;
2549 	    ++len;
2550 	}
2551 	// nothing appended: use 'ignorecase' if not in Vim script
2552 	else
2553 	    ic = vim9script ? FALSE : p_ic;
2554 
2555 	/*
2556 	 * Get the second variable.
2557 	 */
2558 	if (evaluate && vim9script && !IS_WHITE_OR_NUL(p[len]))
2559 	{
2560 	    error_white_both(p, 1);
2561 	    clear_tv(rettv);
2562 	    return FAIL;
2563 	}
2564 	*arg = skipwhite_and_linebreak(p + len, evalarg);
2565 	if (eval5(arg, &var2, evalarg) == FAIL)
2566 	{
2567 	    clear_tv(rettv);
2568 	    return FAIL;
2569 	}
2570 	if (evaluate)
2571 	{
2572 	    int ret;
2573 
2574 	    if (vim9script && check_compare_types(type, rettv, &var2) == FAIL)
2575 	    {
2576 		ret = FAIL;
2577 		clear_tv(rettv);
2578 	    }
2579 	    else
2580 		ret = typval_compare(rettv, &var2, type, ic);
2581 	    clear_tv(&var2);
2582 	    return ret;
2583 	}
2584     }
2585 
2586     return OK;
2587 }
2588 
2589     void
2590 eval_addblob(typval_T *tv1, typval_T *tv2)
2591 {
2592     blob_T  *b1 = tv1->vval.v_blob;
2593     blob_T  *b2 = tv2->vval.v_blob;
2594     blob_T  *b = blob_alloc();
2595     int	    i;
2596 
2597     if (b != NULL)
2598     {
2599 	for (i = 0; i < blob_len(b1); i++)
2600 	    ga_append(&b->bv_ga, blob_get(b1, i));
2601 	for (i = 0; i < blob_len(b2); i++)
2602 	    ga_append(&b->bv_ga, blob_get(b2, i));
2603 
2604 	clear_tv(tv1);
2605 	rettv_blob_set(tv1, b);
2606     }
2607 }
2608 
2609     int
2610 eval_addlist(typval_T *tv1, typval_T *tv2)
2611 {
2612     typval_T var3;
2613 
2614     // concatenate Lists
2615     if (list_concat(tv1->vval.v_list, tv2->vval.v_list, &var3) == FAIL)
2616     {
2617 	clear_tv(tv1);
2618 	clear_tv(tv2);
2619 	return FAIL;
2620     }
2621     clear_tv(tv1);
2622     *tv1 = var3;
2623     return OK;
2624 }
2625 
2626 /*
2627  * Handle fourth level expression:
2628  *	+	number addition
2629  *	-	number subtraction
2630  *	.	string concatenation (if script version is 1)
2631  *	..	string concatenation
2632  *
2633  * "arg" must point to the first non-white of the expression.
2634  * "arg" is advanced to just after the recognized expression.
2635  *
2636  * Return OK or FAIL.
2637  */
2638     static int
2639 eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2640 {
2641     /*
2642      * Get the first variable.
2643      */
2644     if (eval6(arg, rettv, evalarg, FALSE) == FAIL)
2645 	return FAIL;
2646 
2647     /*
2648      * Repeat computing, until no '+', '-' or '.' is following.
2649      */
2650     for (;;)
2651     {
2652 	int	    evaluate;
2653 	int	    getnext;
2654 	char_u	    *p;
2655 	int	    op;
2656 	int	    oplen;
2657 	int	    concat;
2658 	typval_T    var2;
2659 
2660 	// "." is only string concatenation when scriptversion is 1
2661 	p = eval_next_non_blank(*arg, evalarg, &getnext);
2662 	op = *p;
2663 	concat = op == '.' && (*(p + 1) == '.' || current_sctx.sc_version < 2);
2664 	if (op != '+' && op != '-' && !concat)
2665 	    break;
2666 
2667 	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
2668 	oplen = (concat && p[1] == '.') ? 2 : 1;
2669 	if (getnext)
2670 	    *arg = eval_next_line(evalarg);
2671 	else
2672 	{
2673 	    if (evaluate && in_vim9script() && !VIM_ISWHITE(**arg))
2674 	    {
2675 		error_white_both(p, oplen);
2676 		clear_tv(rettv);
2677 		return FAIL;
2678 	    }
2679 	    *arg = p;
2680 	}
2681 	if ((op != '+' || (rettv->v_type != VAR_LIST
2682 						 && rettv->v_type != VAR_BLOB))
2683 #ifdef FEAT_FLOAT
2684 		&& (op == '.' || rettv->v_type != VAR_FLOAT)
2685 #endif
2686 		)
2687 	{
2688 	    // For "list + ...", an illegal use of the first operand as
2689 	    // a number cannot be determined before evaluating the 2nd
2690 	    // operand: if this is also a list, all is ok.
2691 	    // For "something . ...", "something - ..." or "non-list + ...",
2692 	    // we know that the first operand needs to be a string or number
2693 	    // without evaluating the 2nd operand.  So check before to avoid
2694 	    // side effects after an error.
2695 	    if (evaluate && tv_get_string_chk(rettv) == NULL)
2696 	    {
2697 		clear_tv(rettv);
2698 		return FAIL;
2699 	    }
2700 	}
2701 
2702 	/*
2703 	 * Get the second variable.
2704 	 */
2705 	if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[oplen]))
2706 	{
2707 	    error_white_both(p, oplen);
2708 	    clear_tv(rettv);
2709 	    return FAIL;
2710 	}
2711 	*arg = skipwhite_and_linebreak(*arg + oplen, evalarg);
2712 	if (eval6(arg, &var2, evalarg, op == '.') == FAIL)
2713 	{
2714 	    clear_tv(rettv);
2715 	    return FAIL;
2716 	}
2717 
2718 	if (evaluate)
2719 	{
2720 	    /*
2721 	     * Compute the result.
2722 	     */
2723 	    if (op == '.')
2724 	    {
2725 		char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
2726 		char_u	*s1 = tv_get_string_buf(rettv, buf1);
2727 		char_u	*s2 = tv_get_string_buf_chk(&var2, buf2);
2728 
2729 		if (s2 == NULL)		// type error ?
2730 		{
2731 		    clear_tv(rettv);
2732 		    clear_tv(&var2);
2733 		    return FAIL;
2734 		}
2735 		p = concat_str(s1, s2);
2736 		clear_tv(rettv);
2737 		rettv->v_type = VAR_STRING;
2738 		rettv->vval.v_string = p;
2739 	    }
2740 	    else if (op == '+' && rettv->v_type == VAR_BLOB
2741 						   && var2.v_type == VAR_BLOB)
2742 		eval_addblob(rettv, &var2);
2743 	    else if (op == '+' && rettv->v_type == VAR_LIST
2744 						   && var2.v_type == VAR_LIST)
2745 	    {
2746 		if (eval_addlist(rettv, &var2) == FAIL)
2747 		    return FAIL;
2748 	    }
2749 	    else
2750 	    {
2751 		int		error = FALSE;
2752 		varnumber_T	n1, n2;
2753 #ifdef FEAT_FLOAT
2754 		float_T	    f1 = 0, f2 = 0;
2755 
2756 		if (rettv->v_type == VAR_FLOAT)
2757 		{
2758 		    f1 = rettv->vval.v_float;
2759 		    n1 = 0;
2760 		}
2761 		else
2762 #endif
2763 		{
2764 		    n1 = tv_get_number_chk(rettv, &error);
2765 		    if (error)
2766 		    {
2767 			// This can only happen for "list + non-list".  For
2768 			// "non-list + ..." or "something - ...", we returned
2769 			// before evaluating the 2nd operand.
2770 			clear_tv(rettv);
2771 			return FAIL;
2772 		    }
2773 #ifdef FEAT_FLOAT
2774 		    if (var2.v_type == VAR_FLOAT)
2775 			f1 = n1;
2776 #endif
2777 		}
2778 #ifdef FEAT_FLOAT
2779 		if (var2.v_type == VAR_FLOAT)
2780 		{
2781 		    f2 = var2.vval.v_float;
2782 		    n2 = 0;
2783 		}
2784 		else
2785 #endif
2786 		{
2787 		    n2 = tv_get_number_chk(&var2, &error);
2788 		    if (error)
2789 		    {
2790 			clear_tv(rettv);
2791 			clear_tv(&var2);
2792 			return FAIL;
2793 		    }
2794 #ifdef FEAT_FLOAT
2795 		    if (rettv->v_type == VAR_FLOAT)
2796 			f2 = n2;
2797 #endif
2798 		}
2799 		clear_tv(rettv);
2800 
2801 #ifdef FEAT_FLOAT
2802 		// If there is a float on either side the result is a float.
2803 		if (rettv->v_type == VAR_FLOAT || var2.v_type == VAR_FLOAT)
2804 		{
2805 		    if (op == '+')
2806 			f1 = f1 + f2;
2807 		    else
2808 			f1 = f1 - f2;
2809 		    rettv->v_type = VAR_FLOAT;
2810 		    rettv->vval.v_float = f1;
2811 		}
2812 		else
2813 #endif
2814 		{
2815 		    if (op == '+')
2816 			n1 = n1 + n2;
2817 		    else
2818 			n1 = n1 - n2;
2819 		    rettv->v_type = VAR_NUMBER;
2820 		    rettv->vval.v_number = n1;
2821 		}
2822 	    }
2823 	    clear_tv(&var2);
2824 	}
2825     }
2826     return OK;
2827 }
2828 
2829 /*
2830  * Handle fifth level expression:
2831  *	*	number multiplication
2832  *	/	number division
2833  *	%	number modulo
2834  *
2835  * "arg" must point to the first non-white of the expression.
2836  * "arg" is advanced to just after the recognized expression.
2837  *
2838  * Return OK or FAIL.
2839  */
2840     static int
2841 eval6(
2842     char_u	**arg,
2843     typval_T	*rettv,
2844     evalarg_T	*evalarg,
2845     int		want_string)  // after "." operator
2846 {
2847 #ifdef FEAT_FLOAT
2848     int	    use_float = FALSE;
2849 #endif
2850 
2851     /*
2852      * Get the first variable.
2853      */
2854     if (eval7(arg, rettv, evalarg, want_string) == FAIL)
2855 	return FAIL;
2856 
2857     /*
2858      * Repeat computing, until no '*', '/' or '%' is following.
2859      */
2860     for (;;)
2861     {
2862 	int	    evaluate;
2863 	int	    getnext;
2864 	typval_T    var2;
2865 	char_u	    *p;
2866 	int	    op;
2867 	varnumber_T n1, n2;
2868 #ifdef FEAT_FLOAT
2869 	float_T	    f1, f2;
2870 #endif
2871 	int	    error;
2872 
2873 	p = eval_next_non_blank(*arg, evalarg, &getnext);
2874 	op = *p;
2875 	if (op != '*' && op != '/' && op != '%')
2876 	    break;
2877 
2878 	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
2879 	if (getnext)
2880 	    *arg = eval_next_line(evalarg);
2881 	else
2882 	{
2883 	    if (evaluate && in_vim9script() && !VIM_ISWHITE(**arg))
2884 	    {
2885 		error_white_both(p, 1);
2886 		clear_tv(rettv);
2887 		return FAIL;
2888 	    }
2889 	    *arg = p;
2890 	}
2891 
2892 #ifdef FEAT_FLOAT
2893 	f1 = 0;
2894 	f2 = 0;
2895 #endif
2896 	error = FALSE;
2897 	if (evaluate)
2898 	{
2899 #ifdef FEAT_FLOAT
2900 	    if (rettv->v_type == VAR_FLOAT)
2901 	    {
2902 		f1 = rettv->vval.v_float;
2903 		use_float = TRUE;
2904 		n1 = 0;
2905 	    }
2906 	    else
2907 #endif
2908 		n1 = tv_get_number_chk(rettv, &error);
2909 	    clear_tv(rettv);
2910 	    if (error)
2911 		return FAIL;
2912 	}
2913 	else
2914 	    n1 = 0;
2915 
2916 	/*
2917 	 * Get the second variable.
2918 	 */
2919 	if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[1]))
2920 	{
2921 	    error_white_both(p, 1);
2922 	    clear_tv(rettv);
2923 	    return FAIL;
2924 	}
2925 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg);
2926 	if (eval7(arg, &var2, evalarg, FALSE) == FAIL)
2927 	    return FAIL;
2928 
2929 	if (evaluate)
2930 	{
2931 #ifdef FEAT_FLOAT
2932 	    if (var2.v_type == VAR_FLOAT)
2933 	    {
2934 		if (!use_float)
2935 		{
2936 		    f1 = n1;
2937 		    use_float = TRUE;
2938 		}
2939 		f2 = var2.vval.v_float;
2940 		n2 = 0;
2941 	    }
2942 	    else
2943 #endif
2944 	    {
2945 		n2 = tv_get_number_chk(&var2, &error);
2946 		clear_tv(&var2);
2947 		if (error)
2948 		    return FAIL;
2949 #ifdef FEAT_FLOAT
2950 		if (use_float)
2951 		    f2 = n2;
2952 #endif
2953 	    }
2954 
2955 	    /*
2956 	     * Compute the result.
2957 	     * When either side is a float the result is a float.
2958 	     */
2959 #ifdef FEAT_FLOAT
2960 	    if (use_float)
2961 	    {
2962 		if (op == '*')
2963 		    f1 = f1 * f2;
2964 		else if (op == '/')
2965 		{
2966 # ifdef VMS
2967 		    // VMS crashes on divide by zero, work around it
2968 		    if (f2 == 0.0)
2969 		    {
2970 			if (f1 == 0)
2971 			    f1 = -1 * __F_FLT_MAX - 1L;   // similar to NaN
2972 			else if (f1 < 0)
2973 			    f1 = -1 * __F_FLT_MAX;
2974 			else
2975 			    f1 = __F_FLT_MAX;
2976 		    }
2977 		    else
2978 			f1 = f1 / f2;
2979 # else
2980 		    // We rely on the floating point library to handle divide
2981 		    // by zero to result in "inf" and not a crash.
2982 		    f1 = f1 / f2;
2983 # endif
2984 		}
2985 		else
2986 		{
2987 		    emsg(_(e_modulus));
2988 		    return FAIL;
2989 		}
2990 		rettv->v_type = VAR_FLOAT;
2991 		rettv->vval.v_float = f1;
2992 	    }
2993 	    else
2994 #endif
2995 	    {
2996 		if (op == '*')
2997 		    n1 = n1 * n2;
2998 		else if (op == '/')
2999 		    n1 = num_divide(n1, n2);
3000 		else
3001 		    n1 = num_modulus(n1, n2);
3002 
3003 		rettv->v_type = VAR_NUMBER;
3004 		rettv->vval.v_number = n1;
3005 	    }
3006 	}
3007     }
3008 
3009     return OK;
3010 }
3011 
3012 /*
3013  * Handle sixth level expression:
3014  *  number		number constant
3015  *  0zFFFFFFFF		Blob constant
3016  *  "string"		string constant
3017  *  'string'		literal string constant
3018  *  &option-name	option value
3019  *  @r			register contents
3020  *  identifier		variable value
3021  *  function()		function call
3022  *  $VAR		environment variable
3023  *  (expression)	nested expression
3024  *  [expr, expr]	List
3025  *  {arg, arg -> expr}	Lambda
3026  *  {key: val, key: val}   Dictionary
3027  *  #{key: val, key: val}  Dictionary with literal keys
3028  *
3029  *  Also handle:
3030  *  ! in front		logical NOT
3031  *  - in front		unary minus
3032  *  + in front		unary plus (ignored)
3033  *  trailing []		subscript in String or List
3034  *  trailing .name	entry in Dictionary
3035  *  trailing ->name()	method call
3036  *
3037  * "arg" must point to the first non-white of the expression.
3038  * "arg" is advanced to just after the recognized expression.
3039  *
3040  * Return OK or FAIL.
3041  */
3042     static int
3043 eval7(
3044     char_u	**arg,
3045     typval_T	*rettv,
3046     evalarg_T	*evalarg,
3047     int		want_string)	// after "." operator
3048 {
3049     int		evaluate = evalarg != NULL
3050 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3051     int		len;
3052     char_u	*s;
3053     char_u	*start_leader, *end_leader;
3054     int		ret = OK;
3055     char_u	*alias;
3056 
3057     /*
3058      * Initialise variable so that clear_tv() can't mistake this for a
3059      * string and free a string that isn't there.
3060      */
3061     rettv->v_type = VAR_UNKNOWN;
3062 
3063     /*
3064      * Skip '!', '-' and '+' characters.  They are handled later.
3065      */
3066     start_leader = *arg;
3067     while (**arg == '!' || **arg == '-' || **arg == '+')
3068 	*arg = skipwhite(*arg + 1);
3069     end_leader = *arg;
3070 
3071     if (**arg == '.' && (!isdigit(*(*arg + 1))
3072 #ifdef FEAT_FLOAT
3073 	    || current_sctx.sc_version < 2
3074 #endif
3075 	    ))
3076     {
3077 	semsg(_(e_invexpr2), *arg);
3078 	++*arg;
3079 	return FAIL;
3080     }
3081 
3082     switch (**arg)
3083     {
3084     /*
3085      * Number constant.
3086      */
3087     case '0':
3088     case '1':
3089     case '2':
3090     case '3':
3091     case '4':
3092     case '5':
3093     case '6':
3094     case '7':
3095     case '8':
3096     case '9':
3097     case '.':	ret = eval_number(arg, rettv, evaluate, want_string);
3098 
3099 		// Apply prefixed "-" and "+" now.  Matters especially when
3100 		// "->" follows.
3101 		if (ret == OK && evaluate && end_leader > start_leader)
3102 		    ret = eval7_leader(rettv, TRUE, start_leader, &end_leader);
3103 		break;
3104 
3105     /*
3106      * String constant: "string".
3107      */
3108     case '"':	ret = eval_string(arg, rettv, evaluate);
3109 		break;
3110 
3111     /*
3112      * Literal string constant: 'str''ing'.
3113      */
3114     case '\'':	ret = eval_lit_string(arg, rettv, evaluate);
3115 		break;
3116 
3117     /*
3118      * List: [expr, expr]
3119      */
3120     case '[':	ret = eval_list(arg, rettv, evalarg, TRUE);
3121 		break;
3122 
3123     /*
3124      * Dictionary: #{key: val, key: val}
3125      */
3126     case '#':	if ((*arg)[1] == '{')
3127 		{
3128 		    ++*arg;
3129 		    ret = eval_dict(arg, rettv, evalarg, TRUE);
3130 		}
3131 		else
3132 		    ret = NOTDONE;
3133 		break;
3134 
3135     /*
3136      * Lambda: {arg, arg -> expr}
3137      * Dictionary: {'key': val, 'key': val}
3138      */
3139     case '{':	ret = get_lambda_tv(arg, rettv, evalarg);
3140 		if (ret == NOTDONE)
3141 		    ret = eval_dict(arg, rettv, evalarg, FALSE);
3142 		break;
3143 
3144     /*
3145      * Option value: &name
3146      */
3147     case '&':	ret = eval_option(arg, rettv, evaluate);
3148 		break;
3149 
3150     /*
3151      * Environment variable: $VAR.
3152      */
3153     case '$':	ret = eval_env_var(arg, rettv, evaluate);
3154 		break;
3155 
3156     /*
3157      * Register contents: @r.
3158      */
3159     case '@':	++*arg;
3160 		if (evaluate)
3161 		{
3162 		    rettv->v_type = VAR_STRING;
3163 		    rettv->vval.v_string = get_reg_contents(**arg,
3164 							    GREG_EXPR_SRC);
3165 		}
3166 		if (**arg != NUL)
3167 		    ++*arg;
3168 		break;
3169 
3170     /*
3171      * nested expression: (expression).
3172      */
3173     case '(':	{
3174 		    *arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3175 		    ret = eval1(arg, rettv, evalarg);	// recursive!
3176 
3177 		    *arg = skipwhite_and_linebreak(*arg, evalarg);
3178 		    if (**arg == ')')
3179 			++*arg;
3180 		    else if (ret == OK)
3181 		    {
3182 			emsg(_(e_missing_close));
3183 			clear_tv(rettv);
3184 			ret = FAIL;
3185 		    }
3186 		}
3187 		break;
3188 
3189     default:	ret = NOTDONE;
3190 		break;
3191     }
3192 
3193     if (ret == NOTDONE)
3194     {
3195 	/*
3196 	 * Must be a variable or function name.
3197 	 * Can also be a curly-braces kind of name: {expr}.
3198 	 */
3199 	s = *arg;
3200 	len = get_name_len(arg, &alias, evaluate, TRUE);
3201 	if (alias != NULL)
3202 	    s = alias;
3203 
3204 	if (len <= 0)
3205 	    ret = FAIL;
3206 	else
3207 	{
3208 	    int	    flags = evalarg == NULL ? 0 : evalarg->eval_flags;
3209 
3210 	    if ((in_vim9script() ? **arg : *skipwhite(*arg)) == '(')
3211 	    {
3212 		// "name(..."  recursive!
3213 		*arg = skipwhite(*arg);
3214 		ret = eval_func(arg, evalarg, s, len, rettv, flags, NULL);
3215 	    }
3216 	    else if (flags & EVAL_CONSTANT)
3217 		ret = FAIL;
3218 	    else if (evaluate)
3219 	    {
3220 		// get the value of "true", "false" or a variable
3221 		if (len == 4 && in_vim9script() && STRNCMP(s, "true", 4) == 0)
3222 		{
3223 		    rettv->v_type = VAR_BOOL;
3224 		    rettv->vval.v_number = VVAL_TRUE;
3225 		}
3226 		else if (len == 5 && in_vim9script()
3227 						&& STRNCMP(s, "false", 4) == 0)
3228 		{
3229 		    rettv->v_type = VAR_BOOL;
3230 		    rettv->vval.v_number = VVAL_FALSE;
3231 		}
3232 		else
3233 		    ret = eval_variable(s, len, rettv, NULL, TRUE, FALSE);
3234 	    }
3235 	    else
3236 	    {
3237 		// skip the name
3238 		check_vars(s, len);
3239 		ret = OK;
3240 	    }
3241 	}
3242 	vim_free(alias);
3243     }
3244 
3245     // Handle following '[', '(' and '.' for expr[expr], expr.name,
3246     // expr(expr), expr->name(expr)
3247     if (ret == OK)
3248 	ret = handle_subscript(arg, rettv, evalarg, TRUE);
3249 
3250     /*
3251      * Apply logical NOT and unary '-', from right to left, ignore '+'.
3252      */
3253     if (ret == OK && evaluate && end_leader > start_leader)
3254 	ret = eval7_leader(rettv, FALSE, start_leader, &end_leader);
3255     return ret;
3256 }
3257 
3258 /*
3259  * Apply the leading "!" and "-" before an eval7 expression to "rettv".
3260  * When "numeric_only" is TRUE only handle "+" and "-".
3261  * Adjusts "end_leaderp" until it is at "start_leader".
3262  */
3263     static int
3264 eval7_leader(
3265 	typval_T    *rettv,
3266 	int	    numeric_only,
3267 	char_u	    *start_leader,
3268 	char_u	    **end_leaderp)
3269 {
3270     char_u	*end_leader = *end_leaderp;
3271     int		ret = OK;
3272     int		error = FALSE;
3273     varnumber_T val = 0;
3274 #ifdef FEAT_FLOAT
3275     float_T	    f = 0.0;
3276 
3277     if (rettv->v_type == VAR_FLOAT)
3278 	f = rettv->vval.v_float;
3279     else
3280 #endif
3281 	val = tv_get_number_chk(rettv, &error);
3282     if (error)
3283     {
3284 	clear_tv(rettv);
3285 	ret = FAIL;
3286     }
3287     else
3288     {
3289 	while (end_leader > start_leader)
3290 	{
3291 	    --end_leader;
3292 	    if (*end_leader == '!')
3293 	    {
3294 		if (numeric_only)
3295 		{
3296 		    ++end_leader;
3297 		    break;
3298 		}
3299 #ifdef FEAT_FLOAT
3300 		if (rettv->v_type == VAR_FLOAT)
3301 		    f = !f;
3302 		else
3303 #endif
3304 		    val = !val;
3305 	    }
3306 	    else if (*end_leader == '-')
3307 	    {
3308 #ifdef FEAT_FLOAT
3309 		if (rettv->v_type == VAR_FLOAT)
3310 		    f = -f;
3311 		else
3312 #endif
3313 		    val = -val;
3314 	    }
3315 	}
3316 #ifdef FEAT_FLOAT
3317 	if (rettv->v_type == VAR_FLOAT)
3318 	{
3319 	    clear_tv(rettv);
3320 	    rettv->vval.v_float = f;
3321 	}
3322 	else
3323 #endif
3324 	{
3325 	    clear_tv(rettv);
3326 	    rettv->v_type = VAR_NUMBER;
3327 	    rettv->vval.v_number = val;
3328 	}
3329     }
3330     *end_leaderp = end_leader;
3331     return ret;
3332 }
3333 
3334 /*
3335  * Call the function referred to in "rettv".
3336  */
3337     static int
3338 call_func_rettv(
3339 	char_u	    **arg,
3340 	evalarg_T   *evalarg,
3341 	typval_T    *rettv,
3342 	int	    evaluate,
3343 	dict_T	    *selfdict,
3344 	typval_T    *basetv)
3345 {
3346     partial_T	*pt = NULL;
3347     funcexe_T	funcexe;
3348     typval_T	functv;
3349     char_u	*s;
3350     int		ret;
3351 
3352     // need to copy the funcref so that we can clear rettv
3353     if (evaluate)
3354     {
3355 	functv = *rettv;
3356 	rettv->v_type = VAR_UNKNOWN;
3357 
3358 	// Invoke the function.  Recursive!
3359 	if (functv.v_type == VAR_PARTIAL)
3360 	{
3361 	    pt = functv.vval.v_partial;
3362 	    s = partial_name(pt);
3363 	}
3364 	else
3365 	    s = functv.vval.v_string;
3366     }
3367     else
3368 	s = (char_u *)"";
3369 
3370     CLEAR_FIELD(funcexe);
3371     funcexe.firstline = curwin->w_cursor.lnum;
3372     funcexe.lastline = curwin->w_cursor.lnum;
3373     funcexe.evaluate = evaluate;
3374     funcexe.partial = pt;
3375     funcexe.selfdict = selfdict;
3376     funcexe.basetv = basetv;
3377     ret = get_func_tv(s, -1, rettv, arg, evalarg, &funcexe);
3378 
3379     // Clear the funcref afterwards, so that deleting it while
3380     // evaluating the arguments is possible (see test55).
3381     if (evaluate)
3382 	clear_tv(&functv);
3383 
3384     return ret;
3385 }
3386 
3387 /*
3388  * Evaluate "->method()".
3389  * "*arg" points to the '-'.
3390  * Returns FAIL or OK. "*arg" is advanced to after the ')'.
3391  */
3392     static int
3393 eval_lambda(
3394     char_u	**arg,
3395     typval_T	*rettv,
3396     evalarg_T	*evalarg,
3397     int		verbose)	// give error messages
3398 {
3399     int		evaluate = evalarg != NULL
3400 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3401     typval_T	base = *rettv;
3402     int		ret;
3403 
3404     // Skip over the ->.
3405     *arg += 2;
3406     rettv->v_type = VAR_UNKNOWN;
3407 
3408     ret = get_lambda_tv(arg, rettv, evalarg);
3409     if (ret != OK)
3410 	return FAIL;
3411     else if (**arg != '(')
3412     {
3413 	if (verbose)
3414 	{
3415 	    if (*skipwhite(*arg) == '(')
3416 		emsg(_(e_nowhitespace));
3417 	    else
3418 		semsg(_(e_missing_paren), "lambda");
3419 	}
3420 	clear_tv(rettv);
3421 	ret = FAIL;
3422     }
3423     else
3424 	ret = call_func_rettv(arg, evalarg, rettv, evaluate, NULL, &base);
3425 
3426     // Clear the funcref afterwards, so that deleting it while
3427     // evaluating the arguments is possible (see test55).
3428     if (evaluate)
3429 	clear_tv(&base);
3430 
3431     return ret;
3432 }
3433 
3434 /*
3435  * Evaluate "->method()".
3436  * "*arg" points to the '-'.
3437  * Returns FAIL or OK. "*arg" is advanced to after the ')'.
3438  */
3439     static int
3440 eval_method(
3441     char_u	**arg,
3442     typval_T	*rettv,
3443     evalarg_T	*evalarg,
3444     int		verbose)	// give error messages
3445 {
3446     char_u	*name;
3447     long	len;
3448     char_u	*alias;
3449     typval_T	base = *rettv;
3450     int		ret;
3451     int		evaluate = evalarg != NULL
3452 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3453 
3454     // Skip over the ->.
3455     *arg += 2;
3456     rettv->v_type = VAR_UNKNOWN;
3457 
3458     name = *arg;
3459     len = get_name_len(arg, &alias, evaluate, TRUE);
3460     if (alias != NULL)
3461 	name = alias;
3462 
3463     if (len <= 0)
3464     {
3465 	if (verbose)
3466 	    emsg(_("E260: Missing name after ->"));
3467 	ret = FAIL;
3468     }
3469     else
3470     {
3471 	*arg = skipwhite(*arg);
3472 	if (**arg != '(')
3473 	{
3474 	    if (verbose)
3475 		semsg(_(e_missing_paren), name);
3476 	    ret = FAIL;
3477 	}
3478 	else if (VIM_ISWHITE((*arg)[-1]))
3479 	{
3480 	    if (verbose)
3481 		emsg(_(e_nowhitespace));
3482 	    ret = FAIL;
3483 	}
3484 	else
3485 	    ret = eval_func(arg, evalarg, name, len, rettv,
3486 					  evaluate ? EVAL_EVALUATE : 0, &base);
3487     }
3488 
3489     // Clear the funcref afterwards, so that deleting it while
3490     // evaluating the arguments is possible (see test55).
3491     if (evaluate)
3492 	clear_tv(&base);
3493 
3494     return ret;
3495 }
3496 
3497 /*
3498  * Evaluate an "[expr]" or "[expr:expr]" index.  Also "dict.key".
3499  * "*arg" points to the '[' or '.'.
3500  * Returns FAIL or OK. "*arg" is advanced to after the ']'.
3501  */
3502     static int
3503 eval_index(
3504     char_u	**arg,
3505     typval_T	*rettv,
3506     evalarg_T	*evalarg,
3507     int		verbose)	// give error messages
3508 {
3509     int		evaluate = evalarg != NULL
3510 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3511     int		empty1 = FALSE, empty2 = FALSE;
3512     typval_T	var1, var2;
3513     long	i;
3514     long	n1, n2 = 0;
3515     long	len = -1;
3516     int		range = FALSE;
3517     char_u	*s;
3518     char_u	*key = NULL;
3519 
3520     switch (rettv->v_type)
3521     {
3522 	case VAR_FUNC:
3523 	case VAR_PARTIAL:
3524 	    if (verbose)
3525 		emsg(_("E695: Cannot index a Funcref"));
3526 	    return FAIL;
3527 	case VAR_FLOAT:
3528 #ifdef FEAT_FLOAT
3529 	    if (verbose)
3530 		emsg(_(e_float_as_string));
3531 	    return FAIL;
3532 #endif
3533 	case VAR_BOOL:
3534 	case VAR_SPECIAL:
3535 	case VAR_JOB:
3536 	case VAR_CHANNEL:
3537 	    if (verbose)
3538 		emsg(_("E909: Cannot index a special variable"));
3539 	    return FAIL;
3540 	case VAR_UNKNOWN:
3541 	case VAR_ANY:
3542 	case VAR_VOID:
3543 	    if (evaluate)
3544 		return FAIL;
3545 	    // FALLTHROUGH
3546 
3547 	case VAR_STRING:
3548 	case VAR_NUMBER:
3549 	case VAR_LIST:
3550 	case VAR_DICT:
3551 	case VAR_BLOB:
3552 	    break;
3553     }
3554 
3555     init_tv(&var1);
3556     init_tv(&var2);
3557     if (**arg == '.')
3558     {
3559 	/*
3560 	 * dict.name
3561 	 */
3562 	key = *arg + 1;
3563 	for (len = 0; eval_isdictc(key[len]); ++len)
3564 	    ;
3565 	if (len == 0)
3566 	    return FAIL;
3567 	*arg = skipwhite(key + len);
3568     }
3569     else
3570     {
3571 	/*
3572 	 * something[idx]
3573 	 *
3574 	 * Get the (first) variable from inside the [].
3575 	 */
3576 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3577 	if (**arg == ':')
3578 	    empty1 = TRUE;
3579 	else if (eval1(arg, &var1, evalarg) == FAIL)	// recursive!
3580 	    return FAIL;
3581 	else if (evaluate && tv_get_string_chk(&var1) == NULL)
3582 	{
3583 	    // not a number or string
3584 	    clear_tv(&var1);
3585 	    return FAIL;
3586 	}
3587 
3588 	/*
3589 	 * Get the second variable from inside the [:].
3590 	 */
3591 	*arg = skipwhite_and_linebreak(*arg, evalarg);
3592 	if (**arg == ':')
3593 	{
3594 	    range = TRUE;
3595 	    *arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3596 	    if (**arg == ']')
3597 		empty2 = TRUE;
3598 	    else if (eval1(arg, &var2, evalarg) == FAIL)	// recursive!
3599 	    {
3600 		if (!empty1)
3601 		    clear_tv(&var1);
3602 		return FAIL;
3603 	    }
3604 	    else if (evaluate && tv_get_string_chk(&var2) == NULL)
3605 	    {
3606 		// not a number or string
3607 		if (!empty1)
3608 		    clear_tv(&var1);
3609 		clear_tv(&var2);
3610 		return FAIL;
3611 	    }
3612 	}
3613 
3614 	// Check for the ']'.
3615 	*arg = skipwhite_and_linebreak(*arg, evalarg);
3616 	if (**arg != ']')
3617 	{
3618 	    if (verbose)
3619 		emsg(_(e_missbrac));
3620 	    clear_tv(&var1);
3621 	    if (range)
3622 		clear_tv(&var2);
3623 	    return FAIL;
3624 	}
3625 	*arg = skipwhite(*arg + 1);	// skip the ']'
3626     }
3627 
3628     if (evaluate)
3629     {
3630 	n1 = 0;
3631 	if (!empty1 && rettv->v_type != VAR_DICT)
3632 	{
3633 	    n1 = tv_get_number(&var1);
3634 	    clear_tv(&var1);
3635 	}
3636 	if (range)
3637 	{
3638 	    if (empty2)
3639 		n2 = -1;
3640 	    else
3641 	    {
3642 		n2 = tv_get_number(&var2);
3643 		clear_tv(&var2);
3644 	    }
3645 	}
3646 
3647 	switch (rettv->v_type)
3648 	{
3649 	    case VAR_UNKNOWN:
3650 	    case VAR_ANY:
3651 	    case VAR_VOID:
3652 	    case VAR_FUNC:
3653 	    case VAR_PARTIAL:
3654 	    case VAR_FLOAT:
3655 	    case VAR_BOOL:
3656 	    case VAR_SPECIAL:
3657 	    case VAR_JOB:
3658 	    case VAR_CHANNEL:
3659 		break; // not evaluating, skipping over subscript
3660 
3661 	    case VAR_NUMBER:
3662 	    case VAR_STRING:
3663 		s = tv_get_string(rettv);
3664 		len = (long)STRLEN(s);
3665 		if (range)
3666 		{
3667 		    // The resulting variable is a substring.  If the indexes
3668 		    // are out of range the result is empty.
3669 		    if (n1 < 0)
3670 		    {
3671 			n1 = len + n1;
3672 			if (n1 < 0)
3673 			    n1 = 0;
3674 		    }
3675 		    if (n2 < 0)
3676 			n2 = len + n2;
3677 		    else if (n2 >= len)
3678 			n2 = len;
3679 		    if (n1 >= len || n2 < 0 || n1 > n2)
3680 			s = NULL;
3681 		    else
3682 			s = vim_strnsave(s + n1, n2 - n1 + 1);
3683 		}
3684 		else
3685 		{
3686 		    // The resulting variable is a string of a single
3687 		    // character.  If the index is too big or negative the
3688 		    // result is empty.
3689 		    if (n1 >= len || n1 < 0)
3690 			s = NULL;
3691 		    else
3692 			s = vim_strnsave(s + n1, 1);
3693 		}
3694 		clear_tv(rettv);
3695 		rettv->v_type = VAR_STRING;
3696 		rettv->vval.v_string = s;
3697 		break;
3698 
3699 	    case VAR_BLOB:
3700 		len = blob_len(rettv->vval.v_blob);
3701 		if (range)
3702 		{
3703 		    // The resulting variable is a sub-blob.  If the indexes
3704 		    // are out of range the result is empty.
3705 		    if (n1 < 0)
3706 		    {
3707 			n1 = len + n1;
3708 			if (n1 < 0)
3709 			    n1 = 0;
3710 		    }
3711 		    if (n2 < 0)
3712 			n2 = len + n2;
3713 		    else if (n2 >= len)
3714 			n2 = len - 1;
3715 		    if (n1 >= len || n2 < 0 || n1 > n2)
3716 		    {
3717 			clear_tv(rettv);
3718 			rettv->v_type = VAR_BLOB;
3719 			rettv->vval.v_blob = NULL;
3720 		    }
3721 		    else
3722 		    {
3723 			blob_T  *blob = blob_alloc();
3724 
3725 			if (blob != NULL)
3726 			{
3727 			    if (ga_grow(&blob->bv_ga, n2 - n1 + 1) == FAIL)
3728 			    {
3729 				blob_free(blob);
3730 				return FAIL;
3731 			    }
3732 			    blob->bv_ga.ga_len = n2 - n1 + 1;
3733 			    for (i = n1; i <= n2; i++)
3734 				blob_set(blob, i - n1,
3735 					      blob_get(rettv->vval.v_blob, i));
3736 
3737 			    clear_tv(rettv);
3738 			    rettv_blob_set(rettv, blob);
3739 			}
3740 		    }
3741 		}
3742 		else
3743 		{
3744 		    // The resulting variable is a byte value.
3745 		    // If the index is too big or negative that is an error.
3746 		    if (n1 < 0)
3747 			n1 = len + n1;
3748 		    if (n1 < len && n1 >= 0)
3749 		    {
3750 			int v = blob_get(rettv->vval.v_blob, n1);
3751 
3752 			clear_tv(rettv);
3753 			rettv->v_type = VAR_NUMBER;
3754 			rettv->vval.v_number = v;
3755 		    }
3756 		    else
3757 			semsg(_(e_blobidx), n1);
3758 		}
3759 		break;
3760 
3761 	    case VAR_LIST:
3762 		len = list_len(rettv->vval.v_list);
3763 		if (n1 < 0)
3764 		    n1 = len + n1;
3765 		if (!empty1 && (n1 < 0 || n1 >= len))
3766 		{
3767 		    // For a range we allow invalid values and return an empty
3768 		    // list.  A list index out of range is an error.
3769 		    if (!range)
3770 		    {
3771 			if (verbose)
3772 			    semsg(_(e_listidx), n1);
3773 			return FAIL;
3774 		    }
3775 		    n1 = len;
3776 		}
3777 		if (range)
3778 		{
3779 		    list_T	*l;
3780 
3781 		    if (n2 < 0)
3782 			n2 = len + n2;
3783 		    else if (n2 >= len)
3784 			n2 = len - 1;
3785 		    if (!empty2 && (n2 < 0 || n2 + 1 < n1))
3786 			n2 = -1;
3787 		    l = list_slice(rettv->vval.v_list, n1, n2);
3788 		    if (l == NULL)
3789 			return FAIL;
3790 		    clear_tv(rettv);
3791 		    rettv_list_set(rettv, l);
3792 		}
3793 		else
3794 		{
3795 		    copy_tv(&list_find(rettv->vval.v_list, n1)->li_tv, &var1);
3796 		    clear_tv(rettv);
3797 		    *rettv = var1;
3798 		}
3799 		break;
3800 
3801 	    case VAR_DICT:
3802 		if (range)
3803 		{
3804 		    if (verbose)
3805 			emsg(_(e_dictrange));
3806 		    if (len == -1)
3807 			clear_tv(&var1);
3808 		    return FAIL;
3809 		}
3810 		{
3811 		    dictitem_T	*item;
3812 
3813 		    if (len == -1)
3814 		    {
3815 			key = tv_get_string_chk(&var1);
3816 			if (key == NULL)
3817 			{
3818 			    clear_tv(&var1);
3819 			    return FAIL;
3820 			}
3821 		    }
3822 
3823 		    item = dict_find(rettv->vval.v_dict, key, (int)len);
3824 
3825 		    if (item == NULL && verbose)
3826 			semsg(_(e_dictkey), key);
3827 		    if (len == -1)
3828 			clear_tv(&var1);
3829 		    if (item == NULL)
3830 			return FAIL;
3831 
3832 		    copy_tv(&item->di_tv, &var1);
3833 		    clear_tv(rettv);
3834 		    *rettv = var1;
3835 		}
3836 		break;
3837 	}
3838     }
3839 
3840     return OK;
3841 }
3842 
3843 /*
3844  * Return the function name of partial "pt".
3845  */
3846     char_u *
3847 partial_name(partial_T *pt)
3848 {
3849     if (pt->pt_name != NULL)
3850 	return pt->pt_name;
3851     if (pt->pt_func != NULL)
3852 	return pt->pt_func->uf_name;
3853     return (char_u *)"";
3854 }
3855 
3856     static void
3857 partial_free(partial_T *pt)
3858 {
3859     int i;
3860 
3861     for (i = 0; i < pt->pt_argc; ++i)
3862 	clear_tv(&pt->pt_argv[i]);
3863     vim_free(pt->pt_argv);
3864     dict_unref(pt->pt_dict);
3865     if (pt->pt_name != NULL)
3866     {
3867 	func_unref(pt->pt_name);
3868 	vim_free(pt->pt_name);
3869     }
3870     else
3871 	func_ptr_unref(pt->pt_func);
3872 
3873     if (pt->pt_funcstack != NULL)
3874     {
3875 	// Decrease the reference count for the context of a closure.  If down
3876 	// to zero free it and clear the variables on the stack.
3877 	if (--pt->pt_funcstack->fs_refcount == 0)
3878 	{
3879 	    garray_T	*gap = &pt->pt_funcstack->fs_ga;
3880 	    typval_T	*stack = gap->ga_data;
3881 
3882 	    for (i = 0; i < gap->ga_len; ++i)
3883 		clear_tv(stack + i);
3884 	    ga_clear(gap);
3885 	    vim_free(pt->pt_funcstack);
3886 	}
3887 	pt->pt_funcstack = NULL;
3888     }
3889 
3890     vim_free(pt);
3891 }
3892 
3893 /*
3894  * Unreference a closure: decrement the reference count and free it when it
3895  * becomes zero.
3896  */
3897     void
3898 partial_unref(partial_T *pt)
3899 {
3900     if (pt != NULL && --pt->pt_refcount <= 0)
3901 	partial_free(pt);
3902 }
3903 
3904 /*
3905  * Return the next (unique) copy ID.
3906  * Used for serializing nested structures.
3907  */
3908     int
3909 get_copyID(void)
3910 {
3911     current_copyID += COPYID_INC;
3912     return current_copyID;
3913 }
3914 
3915 /*
3916  * Garbage collection for lists and dictionaries.
3917  *
3918  * We use reference counts to be able to free most items right away when they
3919  * are no longer used.  But for composite items it's possible that it becomes
3920  * unused while the reference count is > 0: When there is a recursive
3921  * reference.  Example:
3922  *	:let l = [1, 2, 3]
3923  *	:let d = {9: l}
3924  *	:let l[1] = d
3925  *
3926  * Since this is quite unusual we handle this with garbage collection: every
3927  * once in a while find out which lists and dicts are not referenced from any
3928  * variable.
3929  *
3930  * Here is a good reference text about garbage collection (refers to Python
3931  * but it applies to all reference-counting mechanisms):
3932  *	http://python.ca/nas/python/gc/
3933  */
3934 
3935 /*
3936  * Do garbage collection for lists and dicts.
3937  * When "testing" is TRUE this is called from test_garbagecollect_now().
3938  * Return TRUE if some memory was freed.
3939  */
3940     int
3941 garbage_collect(int testing)
3942 {
3943     int		copyID;
3944     int		abort = FALSE;
3945     buf_T	*buf;
3946     win_T	*wp;
3947     int		did_free = FALSE;
3948     tabpage_T	*tp;
3949 
3950     if (!testing)
3951     {
3952 	// Only do this once.
3953 	want_garbage_collect = FALSE;
3954 	may_garbage_collect = FALSE;
3955 	garbage_collect_at_exit = FALSE;
3956     }
3957 
3958     // The execution stack can grow big, limit the size.
3959     if (exestack.ga_maxlen - exestack.ga_len > 500)
3960     {
3961 	size_t	new_len;
3962 	char_u	*pp;
3963 	int	n;
3964 
3965 	// Keep 150% of the current size, with a minimum of the growth size.
3966 	n = exestack.ga_len / 2;
3967 	if (n < exestack.ga_growsize)
3968 	    n = exestack.ga_growsize;
3969 
3970 	// Don't make it bigger though.
3971 	if (exestack.ga_len + n < exestack.ga_maxlen)
3972 	{
3973 	    new_len = exestack.ga_itemsize * (exestack.ga_len + n);
3974 	    pp = vim_realloc(exestack.ga_data, new_len);
3975 	    if (pp == NULL)
3976 		return FAIL;
3977 	    exestack.ga_maxlen = exestack.ga_len + n;
3978 	    exestack.ga_data = pp;
3979 	}
3980     }
3981 
3982     // We advance by two because we add one for items referenced through
3983     // previous_funccal.
3984     copyID = get_copyID();
3985 
3986     /*
3987      * 1. Go through all accessible variables and mark all lists and dicts
3988      *    with copyID.
3989      */
3990 
3991     // Don't free variables in the previous_funccal list unless they are only
3992     // referenced through previous_funccal.  This must be first, because if
3993     // the item is referenced elsewhere the funccal must not be freed.
3994     abort = abort || set_ref_in_previous_funccal(copyID);
3995 
3996     // script-local variables
3997     abort = abort || garbage_collect_scriptvars(copyID);
3998 
3999     // buffer-local variables
4000     FOR_ALL_BUFFERS(buf)
4001 	abort = abort || set_ref_in_item(&buf->b_bufvar.di_tv, copyID,
4002 								  NULL, NULL);
4003 
4004     // window-local variables
4005     FOR_ALL_TAB_WINDOWS(tp, wp)
4006 	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
4007 								  NULL, NULL);
4008     if (aucmd_win != NULL)
4009 	abort = abort || set_ref_in_item(&aucmd_win->w_winvar.di_tv, copyID,
4010 								  NULL, NULL);
4011 #ifdef FEAT_PROP_POPUP
4012     FOR_ALL_POPUPWINS(wp)
4013 	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
4014 								  NULL, NULL);
4015     FOR_ALL_TABPAGES(tp)
4016 	FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
4017 		abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
4018 								  NULL, NULL);
4019 #endif
4020 
4021     // tabpage-local variables
4022     FOR_ALL_TABPAGES(tp)
4023 	abort = abort || set_ref_in_item(&tp->tp_winvar.di_tv, copyID,
4024 								  NULL, NULL);
4025     // global variables
4026     abort = abort || garbage_collect_globvars(copyID);
4027 
4028     // function-local variables
4029     abort = abort || set_ref_in_call_stack(copyID);
4030 
4031     // named functions (matters for closures)
4032     abort = abort || set_ref_in_functions(copyID);
4033 
4034     // function call arguments, if v:testing is set.
4035     abort = abort || set_ref_in_func_args(copyID);
4036 
4037     // v: vars
4038     abort = abort || garbage_collect_vimvars(copyID);
4039 
4040     // callbacks in buffers
4041     abort = abort || set_ref_in_buffers(copyID);
4042 
4043 #ifdef FEAT_LUA
4044     abort = abort || set_ref_in_lua(copyID);
4045 #endif
4046 
4047 #ifdef FEAT_PYTHON
4048     abort = abort || set_ref_in_python(copyID);
4049 #endif
4050 
4051 #ifdef FEAT_PYTHON3
4052     abort = abort || set_ref_in_python3(copyID);
4053 #endif
4054 
4055 #ifdef FEAT_JOB_CHANNEL
4056     abort = abort || set_ref_in_channel(copyID);
4057     abort = abort || set_ref_in_job(copyID);
4058 #endif
4059 #ifdef FEAT_NETBEANS_INTG
4060     abort = abort || set_ref_in_nb_channel(copyID);
4061 #endif
4062 
4063 #ifdef FEAT_TIMERS
4064     abort = abort || set_ref_in_timer(copyID);
4065 #endif
4066 
4067 #ifdef FEAT_QUICKFIX
4068     abort = abort || set_ref_in_quickfix(copyID);
4069 #endif
4070 
4071 #ifdef FEAT_TERMINAL
4072     abort = abort || set_ref_in_term(copyID);
4073 #endif
4074 
4075 #ifdef FEAT_PROP_POPUP
4076     abort = abort || set_ref_in_popups(copyID);
4077 #endif
4078 
4079     if (!abort)
4080     {
4081 	/*
4082 	 * 2. Free lists and dictionaries that are not referenced.
4083 	 */
4084 	did_free = free_unref_items(copyID);
4085 
4086 	/*
4087 	 * 3. Check if any funccal can be freed now.
4088 	 *    This may call us back recursively.
4089 	 */
4090 	free_unref_funccal(copyID, testing);
4091     }
4092     else if (p_verbose > 0)
4093     {
4094 	verb_msg(_("Not enough memory to set references, garbage collection aborted!"));
4095     }
4096 
4097     return did_free;
4098 }
4099 
4100 /*
4101  * Free lists, dictionaries, channels and jobs that are no longer referenced.
4102  */
4103     static int
4104 free_unref_items(int copyID)
4105 {
4106     int		did_free = FALSE;
4107 
4108     // Let all "free" functions know that we are here.  This means no
4109     // dictionaries, lists, channels or jobs are to be freed, because we will
4110     // do that here.
4111     in_free_unref_items = TRUE;
4112 
4113     /*
4114      * PASS 1: free the contents of the items.  We don't free the items
4115      * themselves yet, so that it is possible to decrement refcount counters
4116      */
4117 
4118     // Go through the list of dicts and free items without the copyID.
4119     did_free |= dict_free_nonref(copyID);
4120 
4121     // Go through the list of lists and free items without the copyID.
4122     did_free |= list_free_nonref(copyID);
4123 
4124 #ifdef FEAT_JOB_CHANNEL
4125     // Go through the list of jobs and free items without the copyID. This
4126     // must happen before doing channels, because jobs refer to channels, but
4127     // the reference from the channel to the job isn't tracked.
4128     did_free |= free_unused_jobs_contents(copyID, COPYID_MASK);
4129 
4130     // Go through the list of channels and free items without the copyID.
4131     did_free |= free_unused_channels_contents(copyID, COPYID_MASK);
4132 #endif
4133 
4134     /*
4135      * PASS 2: free the items themselves.
4136      */
4137     dict_free_items(copyID);
4138     list_free_items(copyID);
4139 
4140 #ifdef FEAT_JOB_CHANNEL
4141     // Go through the list of jobs and free items without the copyID. This
4142     // must happen before doing channels, because jobs refer to channels, but
4143     // the reference from the channel to the job isn't tracked.
4144     free_unused_jobs(copyID, COPYID_MASK);
4145 
4146     // Go through the list of channels and free items without the copyID.
4147     free_unused_channels(copyID, COPYID_MASK);
4148 #endif
4149 
4150     in_free_unref_items = FALSE;
4151 
4152     return did_free;
4153 }
4154 
4155 /*
4156  * Mark all lists and dicts referenced through hashtab "ht" with "copyID".
4157  * "list_stack" is used to add lists to be marked.  Can be NULL.
4158  *
4159  * Returns TRUE if setting references failed somehow.
4160  */
4161     int
4162 set_ref_in_ht(hashtab_T *ht, int copyID, list_stack_T **list_stack)
4163 {
4164     int		todo;
4165     int		abort = FALSE;
4166     hashitem_T	*hi;
4167     hashtab_T	*cur_ht;
4168     ht_stack_T	*ht_stack = NULL;
4169     ht_stack_T	*tempitem;
4170 
4171     cur_ht = ht;
4172     for (;;)
4173     {
4174 	if (!abort)
4175 	{
4176 	    // Mark each item in the hashtab.  If the item contains a hashtab
4177 	    // it is added to ht_stack, if it contains a list it is added to
4178 	    // list_stack.
4179 	    todo = (int)cur_ht->ht_used;
4180 	    for (hi = cur_ht->ht_array; todo > 0; ++hi)
4181 		if (!HASHITEM_EMPTY(hi))
4182 		{
4183 		    --todo;
4184 		    abort = abort || set_ref_in_item(&HI2DI(hi)->di_tv, copyID,
4185 						       &ht_stack, list_stack);
4186 		}
4187 	}
4188 
4189 	if (ht_stack == NULL)
4190 	    break;
4191 
4192 	// take an item from the stack
4193 	cur_ht = ht_stack->ht;
4194 	tempitem = ht_stack;
4195 	ht_stack = ht_stack->prev;
4196 	free(tempitem);
4197     }
4198 
4199     return abort;
4200 }
4201 
4202 /*
4203  * Mark a dict and its items with "copyID".
4204  * Returns TRUE if setting references failed somehow.
4205  */
4206     int
4207 set_ref_in_dict(dict_T *d, int copyID)
4208 {
4209     if (d != NULL && d->dv_copyID != copyID)
4210     {
4211 	d->dv_copyID = copyID;
4212 	return set_ref_in_ht(&d->dv_hashtab, copyID, NULL);
4213     }
4214     return FALSE;
4215 }
4216 
4217 /*
4218  * Mark a list and its items with "copyID".
4219  * Returns TRUE if setting references failed somehow.
4220  */
4221     int
4222 set_ref_in_list(list_T *ll, int copyID)
4223 {
4224     if (ll != NULL && ll->lv_copyID != copyID)
4225     {
4226 	ll->lv_copyID = copyID;
4227 	return set_ref_in_list_items(ll, copyID, NULL);
4228     }
4229     return FALSE;
4230 }
4231 
4232 /*
4233  * Mark all lists and dicts referenced through list "l" with "copyID".
4234  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
4235  *
4236  * Returns TRUE if setting references failed somehow.
4237  */
4238     int
4239 set_ref_in_list_items(list_T *l, int copyID, ht_stack_T **ht_stack)
4240 {
4241     listitem_T	 *li;
4242     int		 abort = FALSE;
4243     list_T	 *cur_l;
4244     list_stack_T *list_stack = NULL;
4245     list_stack_T *tempitem;
4246 
4247     cur_l = l;
4248     for (;;)
4249     {
4250 	if (!abort && cur_l->lv_first != &range_list_item)
4251 	    // Mark each item in the list.  If the item contains a hashtab
4252 	    // it is added to ht_stack, if it contains a list it is added to
4253 	    // list_stack.
4254 	    for (li = cur_l->lv_first; !abort && li != NULL; li = li->li_next)
4255 		abort = abort || set_ref_in_item(&li->li_tv, copyID,
4256 						       ht_stack, &list_stack);
4257 	if (list_stack == NULL)
4258 	    break;
4259 
4260 	// take an item from the stack
4261 	cur_l = list_stack->list;
4262 	tempitem = list_stack;
4263 	list_stack = list_stack->prev;
4264 	free(tempitem);
4265     }
4266 
4267     return abort;
4268 }
4269 
4270 /*
4271  * Mark all lists and dicts referenced through typval "tv" with "copyID".
4272  * "list_stack" is used to add lists to be marked.  Can be NULL.
4273  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
4274  *
4275  * Returns TRUE if setting references failed somehow.
4276  */
4277     int
4278 set_ref_in_item(
4279     typval_T	    *tv,
4280     int		    copyID,
4281     ht_stack_T	    **ht_stack,
4282     list_stack_T    **list_stack)
4283 {
4284     int		abort = FALSE;
4285 
4286     if (tv->v_type == VAR_DICT)
4287     {
4288 	dict_T	*dd = tv->vval.v_dict;
4289 
4290 	if (dd != NULL && dd->dv_copyID != copyID)
4291 	{
4292 	    // Didn't see this dict yet.
4293 	    dd->dv_copyID = copyID;
4294 	    if (ht_stack == NULL)
4295 	    {
4296 		abort = set_ref_in_ht(&dd->dv_hashtab, copyID, list_stack);
4297 	    }
4298 	    else
4299 	    {
4300 		ht_stack_T *newitem = (ht_stack_T*)malloc(sizeof(ht_stack_T));
4301 		if (newitem == NULL)
4302 		    abort = TRUE;
4303 		else
4304 		{
4305 		    newitem->ht = &dd->dv_hashtab;
4306 		    newitem->prev = *ht_stack;
4307 		    *ht_stack = newitem;
4308 		}
4309 	    }
4310 	}
4311     }
4312     else if (tv->v_type == VAR_LIST)
4313     {
4314 	list_T	*ll = tv->vval.v_list;
4315 
4316 	if (ll != NULL && ll->lv_copyID != copyID)
4317 	{
4318 	    // Didn't see this list yet.
4319 	    ll->lv_copyID = copyID;
4320 	    if (list_stack == NULL)
4321 	    {
4322 		abort = set_ref_in_list_items(ll, copyID, ht_stack);
4323 	    }
4324 	    else
4325 	    {
4326 		list_stack_T *newitem = (list_stack_T*)malloc(
4327 							sizeof(list_stack_T));
4328 		if (newitem == NULL)
4329 		    abort = TRUE;
4330 		else
4331 		{
4332 		    newitem->list = ll;
4333 		    newitem->prev = *list_stack;
4334 		    *list_stack = newitem;
4335 		}
4336 	    }
4337 	}
4338     }
4339     else if (tv->v_type == VAR_FUNC)
4340     {
4341 	abort = set_ref_in_func(tv->vval.v_string, NULL, copyID);
4342     }
4343     else if (tv->v_type == VAR_PARTIAL)
4344     {
4345 	partial_T	*pt = tv->vval.v_partial;
4346 	int		i;
4347 
4348 	if (pt != NULL && pt->pt_copyID != copyID)
4349 	{
4350 	    // Didn't see this partial yet.
4351 	    pt->pt_copyID = copyID;
4352 
4353 	    abort = set_ref_in_func(pt->pt_name, pt->pt_func, copyID);
4354 
4355 	    if (pt->pt_dict != NULL)
4356 	    {
4357 		typval_T dtv;
4358 
4359 		dtv.v_type = VAR_DICT;
4360 		dtv.vval.v_dict = pt->pt_dict;
4361 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4362 	    }
4363 
4364 	    for (i = 0; i < pt->pt_argc; ++i)
4365 		abort = abort || set_ref_in_item(&pt->pt_argv[i], copyID,
4366 							ht_stack, list_stack);
4367 	    if (pt->pt_funcstack != NULL)
4368 	    {
4369 		typval_T    *stack = pt->pt_funcstack->fs_ga.ga_data;
4370 
4371 		for (i = 0; i < pt->pt_funcstack->fs_ga.ga_len; ++i)
4372 		    abort = abort || set_ref_in_item(stack + i, copyID,
4373 							 ht_stack, list_stack);
4374 	    }
4375 
4376 	}
4377     }
4378 #ifdef FEAT_JOB_CHANNEL
4379     else if (tv->v_type == VAR_JOB)
4380     {
4381 	job_T	    *job = tv->vval.v_job;
4382 	typval_T    dtv;
4383 
4384 	if (job != NULL && job->jv_copyID != copyID)
4385 	{
4386 	    job->jv_copyID = copyID;
4387 	    if (job->jv_channel != NULL)
4388 	    {
4389 		dtv.v_type = VAR_CHANNEL;
4390 		dtv.vval.v_channel = job->jv_channel;
4391 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4392 	    }
4393 	    if (job->jv_exit_cb.cb_partial != NULL)
4394 	    {
4395 		dtv.v_type = VAR_PARTIAL;
4396 		dtv.vval.v_partial = job->jv_exit_cb.cb_partial;
4397 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4398 	    }
4399 	}
4400     }
4401     else if (tv->v_type == VAR_CHANNEL)
4402     {
4403 	channel_T   *ch =tv->vval.v_channel;
4404 	ch_part_T   part;
4405 	typval_T    dtv;
4406 	jsonq_T	    *jq;
4407 	cbq_T	    *cq;
4408 
4409 	if (ch != NULL && ch->ch_copyID != copyID)
4410 	{
4411 	    ch->ch_copyID = copyID;
4412 	    for (part = PART_SOCK; part < PART_COUNT; ++part)
4413 	    {
4414 		for (jq = ch->ch_part[part].ch_json_head.jq_next; jq != NULL;
4415 							     jq = jq->jq_next)
4416 		    set_ref_in_item(jq->jq_value, copyID, ht_stack, list_stack);
4417 		for (cq = ch->ch_part[part].ch_cb_head.cq_next; cq != NULL;
4418 							     cq = cq->cq_next)
4419 		    if (cq->cq_callback.cb_partial != NULL)
4420 		    {
4421 			dtv.v_type = VAR_PARTIAL;
4422 			dtv.vval.v_partial = cq->cq_callback.cb_partial;
4423 			set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4424 		    }
4425 		if (ch->ch_part[part].ch_callback.cb_partial != NULL)
4426 		{
4427 		    dtv.v_type = VAR_PARTIAL;
4428 		    dtv.vval.v_partial =
4429 				      ch->ch_part[part].ch_callback.cb_partial;
4430 		    set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4431 		}
4432 	    }
4433 	    if (ch->ch_callback.cb_partial != NULL)
4434 	    {
4435 		dtv.v_type = VAR_PARTIAL;
4436 		dtv.vval.v_partial = ch->ch_callback.cb_partial;
4437 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4438 	    }
4439 	    if (ch->ch_close_cb.cb_partial != NULL)
4440 	    {
4441 		dtv.v_type = VAR_PARTIAL;
4442 		dtv.vval.v_partial = ch->ch_close_cb.cb_partial;
4443 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4444 	    }
4445 	}
4446     }
4447 #endif
4448     return abort;
4449 }
4450 
4451 /*
4452  * Return a string with the string representation of a variable.
4453  * If the memory is allocated "tofree" is set to it, otherwise NULL.
4454  * "numbuf" is used for a number.
4455  * When "copyID" is not NULL replace recursive lists and dicts with "...".
4456  * When both "echo_style" and "composite_val" are FALSE, put quotes around
4457  * stings as "string()", otherwise does not put quotes around strings, as
4458  * ":echo" displays values.
4459  * When "restore_copyID" is FALSE, repeated items in dictionaries and lists
4460  * are replaced with "...".
4461  * May return NULL.
4462  */
4463     char_u *
4464 echo_string_core(
4465     typval_T	*tv,
4466     char_u	**tofree,
4467     char_u	*numbuf,
4468     int		copyID,
4469     int		echo_style,
4470     int		restore_copyID,
4471     int		composite_val)
4472 {
4473     static int	recurse = 0;
4474     char_u	*r = NULL;
4475 
4476     if (recurse >= DICT_MAXNEST)
4477     {
4478 	if (!did_echo_string_emsg)
4479 	{
4480 	    // Only give this message once for a recursive call to avoid
4481 	    // flooding the user with errors.  And stop iterating over lists
4482 	    // and dicts.
4483 	    did_echo_string_emsg = TRUE;
4484 	    emsg(_("E724: variable nested too deep for displaying"));
4485 	}
4486 	*tofree = NULL;
4487 	return (char_u *)"{E724}";
4488     }
4489     ++recurse;
4490 
4491     switch (tv->v_type)
4492     {
4493 	case VAR_STRING:
4494 	    if (echo_style && !composite_val)
4495 	    {
4496 		*tofree = NULL;
4497 		r = tv->vval.v_string;
4498 		if (r == NULL)
4499 		    r = (char_u *)"";
4500 	    }
4501 	    else
4502 	    {
4503 		*tofree = string_quote(tv->vval.v_string, FALSE);
4504 		r = *tofree;
4505 	    }
4506 	    break;
4507 
4508 	case VAR_FUNC:
4509 	    if (echo_style)
4510 	    {
4511 		*tofree = NULL;
4512 		r = tv->vval.v_string;
4513 	    }
4514 	    else
4515 	    {
4516 		*tofree = string_quote(tv->vval.v_string, TRUE);
4517 		r = *tofree;
4518 	    }
4519 	    break;
4520 
4521 	case VAR_PARTIAL:
4522 	    {
4523 		partial_T   *pt = tv->vval.v_partial;
4524 		char_u	    *fname = string_quote(pt == NULL ? NULL
4525 						    : partial_name(pt), FALSE);
4526 		garray_T    ga;
4527 		int	    i;
4528 		char_u	    *tf;
4529 
4530 		ga_init2(&ga, 1, 100);
4531 		ga_concat(&ga, (char_u *)"function(");
4532 		if (fname != NULL)
4533 		{
4534 		    ga_concat(&ga, fname);
4535 		    vim_free(fname);
4536 		}
4537 		if (pt != NULL && pt->pt_argc > 0)
4538 		{
4539 		    ga_concat(&ga, (char_u *)", [");
4540 		    for (i = 0; i < pt->pt_argc; ++i)
4541 		    {
4542 			if (i > 0)
4543 			    ga_concat(&ga, (char_u *)", ");
4544 			ga_concat(&ga,
4545 			     tv2string(&pt->pt_argv[i], &tf, numbuf, copyID));
4546 			vim_free(tf);
4547 		    }
4548 		    ga_concat(&ga, (char_u *)"]");
4549 		}
4550 		if (pt != NULL && pt->pt_dict != NULL)
4551 		{
4552 		    typval_T dtv;
4553 
4554 		    ga_concat(&ga, (char_u *)", ");
4555 		    dtv.v_type = VAR_DICT;
4556 		    dtv.vval.v_dict = pt->pt_dict;
4557 		    ga_concat(&ga, tv2string(&dtv, &tf, numbuf, copyID));
4558 		    vim_free(tf);
4559 		}
4560 		ga_concat(&ga, (char_u *)")");
4561 
4562 		*tofree = ga.ga_data;
4563 		r = *tofree;
4564 		break;
4565 	    }
4566 
4567 	case VAR_BLOB:
4568 	    r = blob2string(tv->vval.v_blob, tofree, numbuf);
4569 	    break;
4570 
4571 	case VAR_LIST:
4572 	    if (tv->vval.v_list == NULL)
4573 	    {
4574 		// NULL list is equivalent to empty list.
4575 		*tofree = NULL;
4576 		r = (char_u *)"[]";
4577 	    }
4578 	    else if (copyID != 0 && tv->vval.v_list->lv_copyID == copyID
4579 		    && tv->vval.v_list->lv_len > 0)
4580 	    {
4581 		*tofree = NULL;
4582 		r = (char_u *)"[...]";
4583 	    }
4584 	    else
4585 	    {
4586 		int old_copyID = tv->vval.v_list->lv_copyID;
4587 
4588 		tv->vval.v_list->lv_copyID = copyID;
4589 		*tofree = list2string(tv, copyID, restore_copyID);
4590 		if (restore_copyID)
4591 		    tv->vval.v_list->lv_copyID = old_copyID;
4592 		r = *tofree;
4593 	    }
4594 	    break;
4595 
4596 	case VAR_DICT:
4597 	    if (tv->vval.v_dict == NULL)
4598 	    {
4599 		// NULL dict is equivalent to empty dict.
4600 		*tofree = NULL;
4601 		r = (char_u *)"{}";
4602 	    }
4603 	    else if (copyID != 0 && tv->vval.v_dict->dv_copyID == copyID
4604 		    && tv->vval.v_dict->dv_hashtab.ht_used != 0)
4605 	    {
4606 		*tofree = NULL;
4607 		r = (char_u *)"{...}";
4608 	    }
4609 	    else
4610 	    {
4611 		int old_copyID = tv->vval.v_dict->dv_copyID;
4612 
4613 		tv->vval.v_dict->dv_copyID = copyID;
4614 		*tofree = dict2string(tv, copyID, restore_copyID);
4615 		if (restore_copyID)
4616 		    tv->vval.v_dict->dv_copyID = old_copyID;
4617 		r = *tofree;
4618 	    }
4619 	    break;
4620 
4621 	case VAR_NUMBER:
4622 	case VAR_UNKNOWN:
4623 	case VAR_ANY:
4624 	case VAR_VOID:
4625 	    *tofree = NULL;
4626 	    r = tv_get_string_buf(tv, numbuf);
4627 	    break;
4628 
4629 	case VAR_JOB:
4630 	case VAR_CHANNEL:
4631 	    *tofree = NULL;
4632 	    r = tv_get_string_buf(tv, numbuf);
4633 	    if (composite_val)
4634 	    {
4635 		*tofree = string_quote(r, FALSE);
4636 		r = *tofree;
4637 	    }
4638 	    break;
4639 
4640 	case VAR_FLOAT:
4641 #ifdef FEAT_FLOAT
4642 	    *tofree = NULL;
4643 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv->vval.v_float);
4644 	    r = numbuf;
4645 	    break;
4646 #endif
4647 
4648 	case VAR_BOOL:
4649 	case VAR_SPECIAL:
4650 	    *tofree = NULL;
4651 	    r = (char_u *)get_var_special_name(tv->vval.v_number);
4652 	    break;
4653     }
4654 
4655     if (--recurse == 0)
4656 	did_echo_string_emsg = FALSE;
4657     return r;
4658 }
4659 
4660 /*
4661  * Return a string with the string representation of a variable.
4662  * If the memory is allocated "tofree" is set to it, otherwise NULL.
4663  * "numbuf" is used for a number.
4664  * Does not put quotes around strings, as ":echo" displays values.
4665  * When "copyID" is not NULL replace recursive lists and dicts with "...".
4666  * May return NULL.
4667  */
4668     char_u *
4669 echo_string(
4670     typval_T	*tv,
4671     char_u	**tofree,
4672     char_u	*numbuf,
4673     int		copyID)
4674 {
4675     return echo_string_core(tv, tofree, numbuf, copyID, TRUE, FALSE, FALSE);
4676 }
4677 
4678 /*
4679  * Return string "str" in ' quotes, doubling ' characters.
4680  * If "str" is NULL an empty string is assumed.
4681  * If "function" is TRUE make it function('string').
4682  */
4683     char_u *
4684 string_quote(char_u *str, int function)
4685 {
4686     unsigned	len;
4687     char_u	*p, *r, *s;
4688 
4689     len = (function ? 13 : 3);
4690     if (str != NULL)
4691     {
4692 	len += (unsigned)STRLEN(str);
4693 	for (p = str; *p != NUL; MB_PTR_ADV(p))
4694 	    if (*p == '\'')
4695 		++len;
4696     }
4697     s = r = alloc(len);
4698     if (r != NULL)
4699     {
4700 	if (function)
4701 	{
4702 	    STRCPY(r, "function('");
4703 	    r += 10;
4704 	}
4705 	else
4706 	    *r++ = '\'';
4707 	if (str != NULL)
4708 	    for (p = str; *p != NUL; )
4709 	    {
4710 		if (*p == '\'')
4711 		    *r++ = '\'';
4712 		MB_COPY_CHAR(p, r);
4713 	    }
4714 	*r++ = '\'';
4715 	if (function)
4716 	    *r++ = ')';
4717 	*r++ = NUL;
4718     }
4719     return s;
4720 }
4721 
4722 #if defined(FEAT_FLOAT) || defined(PROTO)
4723 /*
4724  * Convert the string "text" to a floating point number.
4725  * This uses strtod().  setlocale(LC_NUMERIC, "C") has been used to make sure
4726  * this always uses a decimal point.
4727  * Returns the length of the text that was consumed.
4728  */
4729     int
4730 string2float(
4731     char_u	*text,
4732     float_T	*value)	    // result stored here
4733 {
4734     char	*s = (char *)text;
4735     float_T	f;
4736 
4737     // MS-Windows does not deal with "inf" and "nan" properly.
4738     if (STRNICMP(text, "inf", 3) == 0)
4739     {
4740 	*value = INFINITY;
4741 	return 3;
4742     }
4743     if (STRNICMP(text, "-inf", 3) == 0)
4744     {
4745 	*value = -INFINITY;
4746 	return 4;
4747     }
4748     if (STRNICMP(text, "nan", 3) == 0)
4749     {
4750 	*value = NAN;
4751 	return 3;
4752     }
4753     f = strtod(s, &s);
4754     *value = f;
4755     return (int)((char_u *)s - text);
4756 }
4757 #endif
4758 
4759 /*
4760  * Translate a String variable into a position.
4761  * Returns NULL when there is an error.
4762  */
4763     pos_T *
4764 var2fpos(
4765     typval_T	*varp,
4766     int		dollar_lnum,	// TRUE when $ is last line
4767     int		*fnum)		// set to fnum for '0, 'A, etc.
4768 {
4769     char_u		*name;
4770     static pos_T	pos;
4771     pos_T		*pp;
4772 
4773     // Argument can be [lnum, col, coladd].
4774     if (varp->v_type == VAR_LIST)
4775     {
4776 	list_T		*l;
4777 	int		len;
4778 	int		error = FALSE;
4779 	listitem_T	*li;
4780 
4781 	l = varp->vval.v_list;
4782 	if (l == NULL)
4783 	    return NULL;
4784 
4785 	// Get the line number
4786 	pos.lnum = list_find_nr(l, 0L, &error);
4787 	if (error || pos.lnum <= 0 || pos.lnum > curbuf->b_ml.ml_line_count)
4788 	    return NULL;	// invalid line number
4789 
4790 	// Get the column number
4791 	pos.col = list_find_nr(l, 1L, &error);
4792 	if (error)
4793 	    return NULL;
4794 	len = (long)STRLEN(ml_get(pos.lnum));
4795 
4796 	// We accept "$" for the column number: last column.
4797 	li = list_find(l, 1L);
4798 	if (li != NULL && li->li_tv.v_type == VAR_STRING
4799 		&& li->li_tv.vval.v_string != NULL
4800 		&& STRCMP(li->li_tv.vval.v_string, "$") == 0)
4801 	    pos.col = len + 1;
4802 
4803 	// Accept a position up to the NUL after the line.
4804 	if (pos.col == 0 || (int)pos.col > len + 1)
4805 	    return NULL;	// invalid column number
4806 	--pos.col;
4807 
4808 	// Get the virtual offset.  Defaults to zero.
4809 	pos.coladd = list_find_nr(l, 2L, &error);
4810 	if (error)
4811 	    pos.coladd = 0;
4812 
4813 	return &pos;
4814     }
4815 
4816     name = tv_get_string_chk(varp);
4817     if (name == NULL)
4818 	return NULL;
4819     if (name[0] == '.')				// cursor
4820 	return &curwin->w_cursor;
4821     if (name[0] == 'v' && name[1] == NUL)	// Visual start
4822     {
4823 	if (VIsual_active)
4824 	    return &VIsual;
4825 	return &curwin->w_cursor;
4826     }
4827     if (name[0] == '\'')			// mark
4828     {
4829 	pp = getmark_buf_fnum(curbuf, name[1], FALSE, fnum);
4830 	if (pp == NULL || pp == (pos_T *)-1 || pp->lnum <= 0)
4831 	    return NULL;
4832 	return pp;
4833     }
4834 
4835     pos.coladd = 0;
4836 
4837     if (name[0] == 'w' && dollar_lnum)
4838     {
4839 	pos.col = 0;
4840 	if (name[1] == '0')		// "w0": first visible line
4841 	{
4842 	    update_topline();
4843 	    // In silent Ex mode topline is zero, but that's not a valid line
4844 	    // number; use one instead.
4845 	    pos.lnum = curwin->w_topline > 0 ? curwin->w_topline : 1;
4846 	    return &pos;
4847 	}
4848 	else if (name[1] == '$')	// "w$": last visible line
4849 	{
4850 	    validate_botline();
4851 	    // In silent Ex mode botline is zero, return zero then.
4852 	    pos.lnum = curwin->w_botline > 0 ? curwin->w_botline - 1 : 0;
4853 	    return &pos;
4854 	}
4855     }
4856     else if (name[0] == '$')		// last column or line
4857     {
4858 	if (dollar_lnum)
4859 	{
4860 	    pos.lnum = curbuf->b_ml.ml_line_count;
4861 	    pos.col = 0;
4862 	}
4863 	else
4864 	{
4865 	    pos.lnum = curwin->w_cursor.lnum;
4866 	    pos.col = (colnr_T)STRLEN(ml_get_curline());
4867 	}
4868 	return &pos;
4869     }
4870     return NULL;
4871 }
4872 
4873 /*
4874  * Convert list in "arg" into a position and optional file number.
4875  * When "fnump" is NULL there is no file number, only 3 items.
4876  * Note that the column is passed on as-is, the caller may want to decrement
4877  * it to use 1 for the first column.
4878  * Return FAIL when conversion is not possible, doesn't check the position for
4879  * validity.
4880  */
4881     int
4882 list2fpos(
4883     typval_T	*arg,
4884     pos_T	*posp,
4885     int		*fnump,
4886     colnr_T	*curswantp)
4887 {
4888     list_T	*l = arg->vval.v_list;
4889     long	i = 0;
4890     long	n;
4891 
4892     // List must be: [fnum, lnum, col, coladd, curswant], where "fnum" is only
4893     // there when "fnump" isn't NULL; "coladd" and "curswant" are optional.
4894     if (arg->v_type != VAR_LIST
4895 	    || l == NULL
4896 	    || l->lv_len < (fnump == NULL ? 2 : 3)
4897 	    || l->lv_len > (fnump == NULL ? 4 : 5))
4898 	return FAIL;
4899 
4900     if (fnump != NULL)
4901     {
4902 	n = list_find_nr(l, i++, NULL);	// fnum
4903 	if (n < 0)
4904 	    return FAIL;
4905 	if (n == 0)
4906 	    n = curbuf->b_fnum;		// current buffer
4907 	*fnump = n;
4908     }
4909 
4910     n = list_find_nr(l, i++, NULL);	// lnum
4911     if (n < 0)
4912 	return FAIL;
4913     posp->lnum = n;
4914 
4915     n = list_find_nr(l, i++, NULL);	// col
4916     if (n < 0)
4917 	return FAIL;
4918     posp->col = n;
4919 
4920     n = list_find_nr(l, i, NULL);	// off
4921     if (n < 0)
4922 	posp->coladd = 0;
4923     else
4924 	posp->coladd = n;
4925 
4926     if (curswantp != NULL)
4927 	*curswantp = list_find_nr(l, i + 1, NULL);  // curswant
4928 
4929     return OK;
4930 }
4931 
4932 /*
4933  * Get the length of an environment variable name.
4934  * Advance "arg" to the first character after the name.
4935  * Return 0 for error.
4936  */
4937     int
4938 get_env_len(char_u **arg)
4939 {
4940     char_u	*p;
4941     int		len;
4942 
4943     for (p = *arg; vim_isIDc(*p); ++p)
4944 	;
4945     if (p == *arg)	    // no name found
4946 	return 0;
4947 
4948     len = (int)(p - *arg);
4949     *arg = p;
4950     return len;
4951 }
4952 
4953 /*
4954  * Get the length of the name of a function or internal variable.
4955  * "arg" is advanced to after the name.
4956  * Return 0 if something is wrong.
4957  */
4958     int
4959 get_id_len(char_u **arg)
4960 {
4961     char_u	*p;
4962     int		len;
4963 
4964     // Find the end of the name.
4965     for (p = *arg; eval_isnamec(*p); ++p)
4966     {
4967 	if (*p == ':')
4968 	{
4969 	    // "s:" is start of "s:var", but "n:" is not and can be used in
4970 	    // slice "[n:]".  Also "xx:" is not a namespace.
4971 	    len = (int)(p - *arg);
4972 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, **arg) == NULL)
4973 		    || len > 1)
4974 		break;
4975 	}
4976     }
4977     if (p == *arg)	    // no name found
4978 	return 0;
4979 
4980     len = (int)(p - *arg);
4981     *arg = p;
4982 
4983     return len;
4984 }
4985 
4986 /*
4987  * Get the length of the name of a variable or function.
4988  * Only the name is recognized, does not handle ".key" or "[idx]".
4989  * "arg" is advanced to the first non-white character after the name.
4990  * Return -1 if curly braces expansion failed.
4991  * Return 0 if something else is wrong.
4992  * If the name contains 'magic' {}'s, expand them and return the
4993  * expanded name in an allocated string via 'alias' - caller must free.
4994  */
4995     int
4996 get_name_len(
4997     char_u	**arg,
4998     char_u	**alias,
4999     int		evaluate,
5000     int		verbose)
5001 {
5002     int		len;
5003     char_u	*p;
5004     char_u	*expr_start;
5005     char_u	*expr_end;
5006 
5007     *alias = NULL;  // default to no alias
5008 
5009     if ((*arg)[0] == K_SPECIAL && (*arg)[1] == KS_EXTRA
5010 						  && (*arg)[2] == (int)KE_SNR)
5011     {
5012 	// hard coded <SNR>, already translated
5013 	*arg += 3;
5014 	return get_id_len(arg) + 3;
5015     }
5016     len = eval_fname_script(*arg);
5017     if (len > 0)
5018     {
5019 	// literal "<SID>", "s:" or "<SNR>"
5020 	*arg += len;
5021     }
5022 
5023     /*
5024      * Find the end of the name; check for {} construction.
5025      */
5026     p = find_name_end(*arg, &expr_start, &expr_end,
5027 					       len > 0 ? 0 : FNE_CHECK_START);
5028     if (expr_start != NULL)
5029     {
5030 	char_u	*temp_string;
5031 
5032 	if (!evaluate)
5033 	{
5034 	    len += (int)(p - *arg);
5035 	    *arg = skipwhite(p);
5036 	    return len;
5037 	}
5038 
5039 	/*
5040 	 * Include any <SID> etc in the expanded string:
5041 	 * Thus the -len here.
5042 	 */
5043 	temp_string = make_expanded_name(*arg - len, expr_start, expr_end, p);
5044 	if (temp_string == NULL)
5045 	    return -1;
5046 	*alias = temp_string;
5047 	*arg = skipwhite(p);
5048 	return (int)STRLEN(temp_string);
5049     }
5050 
5051     len += get_id_len(arg);
5052     // Only give an error when there is something, otherwise it will be
5053     // reported at a higher level.
5054     if (len == 0 && verbose && **arg != NUL)
5055 	semsg(_(e_invexpr2), *arg);
5056 
5057     return len;
5058 }
5059 
5060 /*
5061  * Find the end of a variable or function name, taking care of magic braces.
5062  * If "expr_start" is not NULL then "expr_start" and "expr_end" are set to the
5063  * start and end of the first magic braces item.
5064  * "flags" can have FNE_INCL_BR and FNE_CHECK_START.
5065  * Return a pointer to just after the name.  Equal to "arg" if there is no
5066  * valid name.
5067  */
5068     char_u *
5069 find_name_end(
5070     char_u	*arg,
5071     char_u	**expr_start,
5072     char_u	**expr_end,
5073     int		flags)
5074 {
5075     int		mb_nest = 0;
5076     int		br_nest = 0;
5077     char_u	*p;
5078     int		len;
5079     int		vim9script = in_vim9script();
5080 
5081     if (expr_start != NULL)
5082     {
5083 	*expr_start = NULL;
5084 	*expr_end = NULL;
5085     }
5086 
5087     // Quick check for valid starting character.
5088     if ((flags & FNE_CHECK_START) && !eval_isnamec1(*arg)
5089 						&& (*arg != '{' || vim9script))
5090 	return arg;
5091 
5092     for (p = arg; *p != NUL
5093 		    && (eval_isnamec(*p)
5094 			|| (*p == '{' && !vim9script)
5095 			|| ((flags & FNE_INCL_BR) && (*p == '['
5096 					 || (*p == '.' && eval_isdictc(p[1]))))
5097 			|| mb_nest != 0
5098 			|| br_nest != 0); MB_PTR_ADV(p))
5099     {
5100 	if (*p == '\'')
5101 	{
5102 	    // skip over 'string' to avoid counting [ and ] inside it.
5103 	    for (p = p + 1; *p != NUL && *p != '\''; MB_PTR_ADV(p))
5104 		;
5105 	    if (*p == NUL)
5106 		break;
5107 	}
5108 	else if (*p == '"')
5109 	{
5110 	    // skip over "str\"ing" to avoid counting [ and ] inside it.
5111 	    for (p = p + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
5112 		if (*p == '\\' && p[1] != NUL)
5113 		    ++p;
5114 	    if (*p == NUL)
5115 		break;
5116 	}
5117 	else if (br_nest == 0 && mb_nest == 0 && *p == ':')
5118 	{
5119 	    // "s:" is start of "s:var", but "n:" is not and can be used in
5120 	    // slice "[n:]".  Also "xx:" is not a namespace. But {ns}: is.
5121 	    len = (int)(p - arg);
5122 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, *arg) == NULL)
5123 		    || (len > 1 && p[-1] != '}'))
5124 		break;
5125 	}
5126 
5127 	if (mb_nest == 0)
5128 	{
5129 	    if (*p == '[')
5130 		++br_nest;
5131 	    else if (*p == ']')
5132 		--br_nest;
5133 	}
5134 
5135 	if (br_nest == 0 && !vim9script)
5136 	{
5137 	    if (*p == '{')
5138 	    {
5139 		mb_nest++;
5140 		if (expr_start != NULL && *expr_start == NULL)
5141 		    *expr_start = p;
5142 	    }
5143 	    else if (*p == '}')
5144 	    {
5145 		mb_nest--;
5146 		if (expr_start != NULL && mb_nest == 0 && *expr_end == NULL)
5147 		    *expr_end = p;
5148 	    }
5149 	}
5150     }
5151 
5152     return p;
5153 }
5154 
5155 /*
5156  * Expands out the 'magic' {}'s in a variable/function name.
5157  * Note that this can call itself recursively, to deal with
5158  * constructs like foo{bar}{baz}{bam}
5159  * The four pointer arguments point to "foo{expre}ss{ion}bar"
5160  *			"in_start"      ^
5161  *			"expr_start"	   ^
5162  *			"expr_end"		 ^
5163  *			"in_end"			    ^
5164  *
5165  * Returns a new allocated string, which the caller must free.
5166  * Returns NULL for failure.
5167  */
5168     static char_u *
5169 make_expanded_name(
5170     char_u	*in_start,
5171     char_u	*expr_start,
5172     char_u	*expr_end,
5173     char_u	*in_end)
5174 {
5175     char_u	c1;
5176     char_u	*retval = NULL;
5177     char_u	*temp_result;
5178 
5179     if (expr_end == NULL || in_end == NULL)
5180 	return NULL;
5181     *expr_start	= NUL;
5182     *expr_end = NUL;
5183     c1 = *in_end;
5184     *in_end = NUL;
5185 
5186     temp_result = eval_to_string(expr_start + 1, FALSE);
5187     if (temp_result != NULL)
5188     {
5189 	retval = alloc(STRLEN(temp_result) + (expr_start - in_start)
5190 						   + (in_end - expr_end) + 1);
5191 	if (retval != NULL)
5192 	{
5193 	    STRCPY(retval, in_start);
5194 	    STRCAT(retval, temp_result);
5195 	    STRCAT(retval, expr_end + 1);
5196 	}
5197     }
5198     vim_free(temp_result);
5199 
5200     *in_end = c1;		// put char back for error messages
5201     *expr_start = '{';
5202     *expr_end = '}';
5203 
5204     if (retval != NULL)
5205     {
5206 	temp_result = find_name_end(retval, &expr_start, &expr_end, 0);
5207 	if (expr_start != NULL)
5208 	{
5209 	    // Further expansion!
5210 	    temp_result = make_expanded_name(retval, expr_start,
5211 						       expr_end, temp_result);
5212 	    vim_free(retval);
5213 	    retval = temp_result;
5214 	}
5215     }
5216 
5217     return retval;
5218 }
5219 
5220 /*
5221  * Return TRUE if character "c" can be used in a variable or function name.
5222  * Does not include '{' or '}' for magic braces.
5223  */
5224     int
5225 eval_isnamec(int c)
5226 {
5227     return ASCII_ISALNUM(c) || c == '_' || c == ':' || c == AUTOLOAD_CHAR;
5228 }
5229 
5230 /*
5231  * Return TRUE if character "c" can be used as the first character in a
5232  * variable or function name (excluding '{' and '}').
5233  */
5234     int
5235 eval_isnamec1(int c)
5236 {
5237     return ASCII_ISALPHA(c) || c == '_';
5238 }
5239 
5240 /*
5241  * Return TRUE if character "c" can be used as the first character of a
5242  * dictionary key.
5243  */
5244     int
5245 eval_isdictc(int c)
5246 {
5247     return ASCII_ISALNUM(c) || c == '_';
5248 }
5249 
5250 /*
5251  * Handle:
5252  * - expr[expr], expr[expr:expr] subscript
5253  * - ".name" lookup
5254  * - function call with Funcref variable: func(expr)
5255  * - method call: var->method()
5256  *
5257  * Can all be combined in any order: dict.func(expr)[idx]['func'](expr)->len()
5258  */
5259     int
5260 handle_subscript(
5261     char_u	**arg,
5262     typval_T	*rettv,
5263     evalarg_T	*evalarg,
5264     int		verbose)	// give error messages
5265 {
5266     int		evaluate = evalarg != NULL
5267 				      && (evalarg->eval_flags & EVAL_EVALUATE);
5268     int		ret = OK;
5269     dict_T	*selfdict = NULL;
5270     int		check_white = TRUE;
5271     int		getnext;
5272     char_u	*p;
5273 
5274     while (ret == OK)
5275     {
5276 	// When at the end of the line and ".name" or "->{" or "->X" follows in
5277 	// the next line then consume the line break.
5278 	p = eval_next_non_blank(*arg, evalarg, &getnext);
5279 	if (getnext
5280 	    && ((rettv->v_type == VAR_DICT && *p == '.' && eval_isdictc(p[1]))
5281 		|| (p[0] == '-' && p[1] == '>'
5282 				     && (p[2] == '{' || ASCII_ISALPHA(p[2])))))
5283 	{
5284 	    *arg = eval_next_line(evalarg);
5285 	    check_white = FALSE;
5286 	}
5287 
5288 	if ((**arg == '(' && (!evaluate || rettv->v_type == VAR_FUNC
5289 			    || rettv->v_type == VAR_PARTIAL))
5290 		    && (!check_white || !VIM_ISWHITE(*(*arg - 1))))
5291 	{
5292 	    ret = call_func_rettv(arg, evalarg, rettv, evaluate,
5293 							       selfdict, NULL);
5294 
5295 	    // Stop the expression evaluation when immediately aborting on
5296 	    // error, or when an interrupt occurred or an exception was thrown
5297 	    // but not caught.
5298 	    if (aborting())
5299 	    {
5300 		if (ret == OK)
5301 		    clear_tv(rettv);
5302 		ret = FAIL;
5303 	    }
5304 	    dict_unref(selfdict);
5305 	    selfdict = NULL;
5306 	}
5307 	else if (p[0] == '-' && p[1] == '>')
5308 	{
5309 	    *arg = p;
5310 	    if (ret == OK)
5311 	    {
5312 		if ((*arg)[2] == '{')
5313 		    // expr->{lambda}()
5314 		    ret = eval_lambda(arg, rettv, evalarg, verbose);
5315 		else
5316 		    // expr->name()
5317 		    ret = eval_method(arg, rettv, evalarg, verbose);
5318 	    }
5319 	}
5320 	// "." is ".name" lookup when we found a dict or when evaluating and
5321 	// scriptversion is at least 2, where string concatenation is "..".
5322 	else if (**arg == '['
5323 		|| (**arg == '.' && (rettv->v_type == VAR_DICT
5324 			|| (!evaluate
5325 			    && (*arg)[1] != '.'
5326 			    && current_sctx.sc_version >= 2))))
5327 	{
5328 	    dict_unref(selfdict);
5329 	    if (rettv->v_type == VAR_DICT)
5330 	    {
5331 		selfdict = rettv->vval.v_dict;
5332 		if (selfdict != NULL)
5333 		    ++selfdict->dv_refcount;
5334 	    }
5335 	    else
5336 		selfdict = NULL;
5337 	    if (eval_index(arg, rettv, evalarg, verbose) == FAIL)
5338 	    {
5339 		clear_tv(rettv);
5340 		ret = FAIL;
5341 	    }
5342 	}
5343 	else
5344 	    break;
5345     }
5346 
5347     // Turn "dict.Func" into a partial for "Func" bound to "dict".
5348     // Don't do this when "Func" is already a partial that was bound
5349     // explicitly (pt_auto is FALSE).
5350     if (selfdict != NULL
5351 	    && (rettv->v_type == VAR_FUNC
5352 		|| (rettv->v_type == VAR_PARTIAL
5353 		    && (rettv->vval.v_partial->pt_auto
5354 			|| rettv->vval.v_partial->pt_dict == NULL))))
5355 	selfdict = make_partial(selfdict, rettv);
5356 
5357     dict_unref(selfdict);
5358     return ret;
5359 }
5360 
5361 /*
5362  * Make a copy of an item.
5363  * Lists and Dictionaries are also copied.  A deep copy if "deep" is set.
5364  * For deepcopy() "copyID" is zero for a full copy or the ID for when a
5365  * reference to an already copied list/dict can be used.
5366  * Returns FAIL or OK.
5367  */
5368     int
5369 item_copy(
5370     typval_T	*from,
5371     typval_T	*to,
5372     int		deep,
5373     int		copyID)
5374 {
5375     static int	recurse = 0;
5376     int		ret = OK;
5377 
5378     if (recurse >= DICT_MAXNEST)
5379     {
5380 	emsg(_("E698: variable nested too deep for making a copy"));
5381 	return FAIL;
5382     }
5383     ++recurse;
5384 
5385     switch (from->v_type)
5386     {
5387 	case VAR_NUMBER:
5388 	case VAR_FLOAT:
5389 	case VAR_STRING:
5390 	case VAR_FUNC:
5391 	case VAR_PARTIAL:
5392 	case VAR_BOOL:
5393 	case VAR_SPECIAL:
5394 	case VAR_JOB:
5395 	case VAR_CHANNEL:
5396 	    copy_tv(from, to);
5397 	    break;
5398 	case VAR_LIST:
5399 	    to->v_type = VAR_LIST;
5400 	    to->v_lock = 0;
5401 	    if (from->vval.v_list == NULL)
5402 		to->vval.v_list = NULL;
5403 	    else if (copyID != 0 && from->vval.v_list->lv_copyID == copyID)
5404 	    {
5405 		// use the copy made earlier
5406 		to->vval.v_list = from->vval.v_list->lv_copylist;
5407 		++to->vval.v_list->lv_refcount;
5408 	    }
5409 	    else
5410 		to->vval.v_list = list_copy(from->vval.v_list, deep, copyID);
5411 	    if (to->vval.v_list == NULL)
5412 		ret = FAIL;
5413 	    break;
5414 	case VAR_BLOB:
5415 	    ret = blob_copy(from->vval.v_blob, to);
5416 	    break;
5417 	case VAR_DICT:
5418 	    to->v_type = VAR_DICT;
5419 	    to->v_lock = 0;
5420 	    if (from->vval.v_dict == NULL)
5421 		to->vval.v_dict = NULL;
5422 	    else if (copyID != 0 && from->vval.v_dict->dv_copyID == copyID)
5423 	    {
5424 		// use the copy made earlier
5425 		to->vval.v_dict = from->vval.v_dict->dv_copydict;
5426 		++to->vval.v_dict->dv_refcount;
5427 	    }
5428 	    else
5429 		to->vval.v_dict = dict_copy(from->vval.v_dict, deep, copyID);
5430 	    if (to->vval.v_dict == NULL)
5431 		ret = FAIL;
5432 	    break;
5433 	case VAR_UNKNOWN:
5434 	case VAR_ANY:
5435 	case VAR_VOID:
5436 	    internal_error_no_abort("item_copy(UNKNOWN)");
5437 	    ret = FAIL;
5438     }
5439     --recurse;
5440     return ret;
5441 }
5442 
5443     void
5444 echo_one(typval_T *rettv, int with_space, int *atstart, int *needclr)
5445 {
5446     char_u	*tofree;
5447     char_u	numbuf[NUMBUFLEN];
5448     char_u	*p = echo_string(rettv, &tofree, numbuf, get_copyID());
5449 
5450     if (*atstart)
5451     {
5452 	*atstart = FALSE;
5453 	// Call msg_start() after eval1(), evaluating the expression
5454 	// may cause a message to appear.
5455 	if (with_space)
5456 	{
5457 	    // Mark the saved text as finishing the line, so that what
5458 	    // follows is displayed on a new line when scrolling back
5459 	    // at the more prompt.
5460 	    msg_sb_eol();
5461 	    msg_start();
5462 	}
5463     }
5464     else if (with_space)
5465 	msg_puts_attr(" ", echo_attr);
5466 
5467     if (p != NULL)
5468 	for ( ; *p != NUL && !got_int; ++p)
5469 	{
5470 	    if (*p == '\n' || *p == '\r' || *p == TAB)
5471 	    {
5472 		if (*p != TAB && *needclr)
5473 		{
5474 		    // remove any text still there from the command
5475 		    msg_clr_eos();
5476 		    *needclr = FALSE;
5477 		}
5478 		msg_putchar_attr(*p, echo_attr);
5479 	    }
5480 	    else
5481 	    {
5482 		if (has_mbyte)
5483 		{
5484 		    int i = (*mb_ptr2len)(p);
5485 
5486 		    (void)msg_outtrans_len_attr(p, i, echo_attr);
5487 		    p += i - 1;
5488 		}
5489 		else
5490 		    (void)msg_outtrans_len_attr(p, 1, echo_attr);
5491 	    }
5492 	}
5493     vim_free(tofree);
5494 }
5495 
5496 /*
5497  * ":echo expr1 ..."	print each argument separated with a space, add a
5498  *			newline at the end.
5499  * ":echon expr1 ..."	print each argument plain.
5500  */
5501     void
5502 ex_echo(exarg_T *eap)
5503 {
5504     char_u	*arg = eap->arg;
5505     typval_T	rettv;
5506     char_u	*p;
5507     int		needclr = TRUE;
5508     int		atstart = TRUE;
5509     int		did_emsg_before = did_emsg;
5510     int		called_emsg_before = called_emsg;
5511     evalarg_T	evalarg;
5512 
5513     fill_evalarg_from_eap(&evalarg, eap, eap->skip);
5514 
5515     if (eap->skip)
5516 	++emsg_skip;
5517     while ((!ends_excmd2(eap->cmd, arg) || *arg == '"') && !got_int)
5518     {
5519 	// If eval1() causes an error message the text from the command may
5520 	// still need to be cleared. E.g., "echo 22,44".
5521 	need_clr_eos = needclr;
5522 
5523 	p = arg;
5524 	if (eval1(&arg, &rettv, &evalarg) == FAIL)
5525 	{
5526 	    /*
5527 	     * Report the invalid expression unless the expression evaluation
5528 	     * has been cancelled due to an aborting error, an interrupt, or an
5529 	     * exception.
5530 	     */
5531 	    if (!aborting() && did_emsg == did_emsg_before
5532 					  && called_emsg == called_emsg_before)
5533 		semsg(_(e_invexpr2), p);
5534 	    need_clr_eos = FALSE;
5535 	    break;
5536 	}
5537 	need_clr_eos = FALSE;
5538 
5539 	if (!eap->skip)
5540 	    echo_one(&rettv, eap->cmdidx == CMD_echo, &atstart, &needclr);
5541 
5542 	clear_tv(&rettv);
5543 	arg = skipwhite(arg);
5544     }
5545     eap->nextcmd = check_nextcmd(arg);
5546     clear_evalarg(&evalarg, eap);
5547 
5548     if (eap->skip)
5549 	--emsg_skip;
5550     else
5551     {
5552 	// remove text that may still be there from the command
5553 	if (needclr)
5554 	    msg_clr_eos();
5555 	if (eap->cmdidx == CMD_echo)
5556 	    msg_end();
5557     }
5558 }
5559 
5560 /*
5561  * ":echohl {name}".
5562  */
5563     void
5564 ex_echohl(exarg_T *eap)
5565 {
5566     echo_attr = syn_name2attr(eap->arg);
5567 }
5568 
5569 /*
5570  * Returns the :echo attribute
5571  */
5572     int
5573 get_echo_attr(void)
5574 {
5575     return echo_attr;
5576 }
5577 
5578 /*
5579  * ":execute expr1 ..."	execute the result of an expression.
5580  * ":echomsg expr1 ..."	Print a message
5581  * ":echoerr expr1 ..."	Print an error
5582  * Each gets spaces around each argument and a newline at the end for
5583  * echo commands
5584  */
5585     void
5586 ex_execute(exarg_T *eap)
5587 {
5588     char_u	*arg = eap->arg;
5589     typval_T	rettv;
5590     int		ret = OK;
5591     char_u	*p;
5592     garray_T	ga;
5593     int		len;
5594 
5595     ga_init2(&ga, 1, 80);
5596 
5597     if (eap->skip)
5598 	++emsg_skip;
5599     while (!ends_excmd2(eap->cmd, arg) || *arg == '"')
5600     {
5601 	ret = eval1_emsg(&arg, &rettv, eap);
5602 	if (ret == FAIL)
5603 	    break;
5604 
5605 	if (!eap->skip)
5606 	{
5607 	    char_u   buf[NUMBUFLEN];
5608 
5609 	    if (eap->cmdidx == CMD_execute)
5610 	    {
5611 		if (rettv.v_type == VAR_CHANNEL || rettv.v_type == VAR_JOB)
5612 		{
5613 		    emsg(_(e_inval_string));
5614 		    p = NULL;
5615 		}
5616 		else
5617 		    p = tv_get_string_buf(&rettv, buf);
5618 	    }
5619 	    else
5620 		p = tv_stringify(&rettv, buf);
5621 	    if (p == NULL)
5622 	    {
5623 		clear_tv(&rettv);
5624 		ret = FAIL;
5625 		break;
5626 	    }
5627 	    len = (int)STRLEN(p);
5628 	    if (ga_grow(&ga, len + 2) == FAIL)
5629 	    {
5630 		clear_tv(&rettv);
5631 		ret = FAIL;
5632 		break;
5633 	    }
5634 	    if (ga.ga_len)
5635 		((char_u *)(ga.ga_data))[ga.ga_len++] = ' ';
5636 	    STRCPY((char_u *)(ga.ga_data) + ga.ga_len, p);
5637 	    ga.ga_len += len;
5638 	}
5639 
5640 	clear_tv(&rettv);
5641 	arg = skipwhite(arg);
5642     }
5643 
5644     if (ret != FAIL && ga.ga_data != NULL)
5645     {
5646 	if (eap->cmdidx == CMD_echomsg || eap->cmdidx == CMD_echoerr)
5647 	{
5648 	    // Mark the already saved text as finishing the line, so that what
5649 	    // follows is displayed on a new line when scrolling back at the
5650 	    // more prompt.
5651 	    msg_sb_eol();
5652 	}
5653 
5654 	if (eap->cmdidx == CMD_echomsg)
5655 	{
5656 	    msg_attr(ga.ga_data, echo_attr);
5657 	    out_flush();
5658 	}
5659 	else if (eap->cmdidx == CMD_echoerr)
5660 	{
5661 	    int		save_did_emsg = did_emsg;
5662 
5663 	    // We don't want to abort following commands, restore did_emsg.
5664 	    emsg(ga.ga_data);
5665 	    if (!force_abort)
5666 		did_emsg = save_did_emsg;
5667 	}
5668 	else if (eap->cmdidx == CMD_execute)
5669 	    do_cmdline((char_u *)ga.ga_data,
5670 		       eap->getline, eap->cookie, DOCMD_NOWAIT|DOCMD_VERBOSE);
5671     }
5672 
5673     ga_clear(&ga);
5674 
5675     if (eap->skip)
5676 	--emsg_skip;
5677 
5678     eap->nextcmd = check_nextcmd(arg);
5679 }
5680 
5681 /*
5682  * Skip over the name of an option: "&option", "&g:option" or "&l:option".
5683  * "arg" points to the "&" or '+' when called, to "option" when returning.
5684  * Returns NULL when no option name found.  Otherwise pointer to the char
5685  * after the option name.
5686  */
5687     char_u *
5688 find_option_end(char_u **arg, int *opt_flags)
5689 {
5690     char_u	*p = *arg;
5691 
5692     ++p;
5693     if (*p == 'g' && p[1] == ':')
5694     {
5695 	*opt_flags = OPT_GLOBAL;
5696 	p += 2;
5697     }
5698     else if (*p == 'l' && p[1] == ':')
5699     {
5700 	*opt_flags = OPT_LOCAL;
5701 	p += 2;
5702     }
5703     else
5704 	*opt_flags = 0;
5705 
5706     if (!ASCII_ISALPHA(*p))
5707 	return NULL;
5708     *arg = p;
5709 
5710     if (p[0] == 't' && p[1] == '_' && p[2] != NUL && p[3] != NUL)
5711 	p += 4;	    // termcap option
5712     else
5713 	while (ASCII_ISALPHA(*p))
5714 	    ++p;
5715     return p;
5716 }
5717 
5718 /*
5719  * Display script name where an item was last set.
5720  * Should only be invoked when 'verbose' is non-zero.
5721  */
5722     void
5723 last_set_msg(sctx_T script_ctx)
5724 {
5725     char_u *p;
5726 
5727     if (script_ctx.sc_sid != 0)
5728     {
5729 	p = home_replace_save(NULL, get_scriptname(script_ctx.sc_sid));
5730 	if (p != NULL)
5731 	{
5732 	    verbose_enter();
5733 	    msg_puts(_("\n\tLast set from "));
5734 	    msg_puts((char *)p);
5735 	    if (script_ctx.sc_lnum > 0)
5736 	    {
5737 		msg_puts(_(line_msg));
5738 		msg_outnum((long)script_ctx.sc_lnum);
5739 	    }
5740 	    verbose_leave();
5741 	    vim_free(p);
5742 	}
5743     }
5744 }
5745 
5746 #endif // FEAT_EVAL
5747 
5748 /*
5749  * Perform a substitution on "str" with pattern "pat" and substitute "sub".
5750  * When "sub" is NULL "expr" is used, must be a VAR_FUNC or VAR_PARTIAL.
5751  * "flags" can be "g" to do a global substitute.
5752  * Returns an allocated string, NULL for error.
5753  */
5754     char_u *
5755 do_string_sub(
5756     char_u	*str,
5757     char_u	*pat,
5758     char_u	*sub,
5759     typval_T	*expr,
5760     char_u	*flags)
5761 {
5762     int		sublen;
5763     regmatch_T	regmatch;
5764     int		i;
5765     int		do_all;
5766     char_u	*tail;
5767     char_u	*end;
5768     garray_T	ga;
5769     char_u	*ret;
5770     char_u	*save_cpo;
5771     char_u	*zero_width = NULL;
5772 
5773     // Make 'cpoptions' empty, so that the 'l' flag doesn't work here
5774     save_cpo = p_cpo;
5775     p_cpo = empty_option;
5776 
5777     ga_init2(&ga, 1, 200);
5778 
5779     do_all = (flags[0] == 'g');
5780 
5781     regmatch.rm_ic = p_ic;
5782     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
5783     if (regmatch.regprog != NULL)
5784     {
5785 	tail = str;
5786 	end = str + STRLEN(str);
5787 	while (vim_regexec_nl(&regmatch, str, (colnr_T)(tail - str)))
5788 	{
5789 	    // Skip empty match except for first match.
5790 	    if (regmatch.startp[0] == regmatch.endp[0])
5791 	    {
5792 		if (zero_width == regmatch.startp[0])
5793 		{
5794 		    // avoid getting stuck on a match with an empty string
5795 		    i = mb_ptr2len(tail);
5796 		    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail,
5797 								   (size_t)i);
5798 		    ga.ga_len += i;
5799 		    tail += i;
5800 		    continue;
5801 		}
5802 		zero_width = regmatch.startp[0];
5803 	    }
5804 
5805 	    /*
5806 	     * Get some space for a temporary buffer to do the substitution
5807 	     * into.  It will contain:
5808 	     * - The text up to where the match is.
5809 	     * - The substituted text.
5810 	     * - The text after the match.
5811 	     */
5812 	    sublen = vim_regsub(&regmatch, sub, expr, tail, FALSE, TRUE, FALSE);
5813 	    if (ga_grow(&ga, (int)((end - tail) + sublen -
5814 			    (regmatch.endp[0] - regmatch.startp[0]))) == FAIL)
5815 	    {
5816 		ga_clear(&ga);
5817 		break;
5818 	    }
5819 
5820 	    // copy the text up to where the match is
5821 	    i = (int)(regmatch.startp[0] - tail);
5822 	    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail, (size_t)i);
5823 	    // add the substituted text
5824 	    (void)vim_regsub(&regmatch, sub, expr, (char_u *)ga.ga_data
5825 					  + ga.ga_len + i, TRUE, TRUE, FALSE);
5826 	    ga.ga_len += i + sublen - 1;
5827 	    tail = regmatch.endp[0];
5828 	    if (*tail == NUL)
5829 		break;
5830 	    if (!do_all)
5831 		break;
5832 	}
5833 
5834 	if (ga.ga_data != NULL)
5835 	    STRCPY((char *)ga.ga_data + ga.ga_len, tail);
5836 
5837 	vim_regfree(regmatch.regprog);
5838     }
5839 
5840     ret = vim_strsave(ga.ga_data == NULL ? str : (char_u *)ga.ga_data);
5841     ga_clear(&ga);
5842     if (p_cpo == empty_option)
5843 	p_cpo = save_cpo;
5844     else
5845 	// Darn, evaluating {sub} expression or {expr} changed the value.
5846 	free_string_option(save_cpo);
5847 
5848     return ret;
5849 }
5850