xref: /vim-8.2.3635/src/eval.c (revision cb80aa2d)
1 /* vi:set ts=8 sts=4 sw=4 noet:
2  *
3  * VIM - Vi IMproved	by Bram Moolenaar
4  *
5  * Do ":help uganda"  in Vim to read copying and usage conditions.
6  * Do ":help credits" in Vim to see a list of people who contributed.
7  * See README.txt for an overview of the Vim source code.
8  */
9 
10 /*
11  * eval.c: Expression evaluation.
12  */
13 #define USING_FLOAT_STUFF
14 
15 #include "vim.h"
16 
17 #if defined(FEAT_EVAL) || defined(PROTO)
18 
19 #ifdef VMS
20 # include <float.h>
21 #endif
22 
23 #define NAMESPACE_CHAR	(char_u *)"abglstvw"
24 
25 /*
26  * When recursively copying lists and dicts we need to remember which ones we
27  * have done to avoid endless recursiveness.  This unique ID is used for that.
28  * The last bit is used for previous_funccal, ignored when comparing.
29  */
30 static int current_copyID = 0;
31 
32 /*
33  * Info used by a ":for" loop.
34  */
35 typedef struct
36 {
37     int		fi_semicolon;	// TRUE if ending in '; var]'
38     int		fi_varcount;	// nr of variables in the list
39     int		fi_break_count;	// nr of line breaks encountered
40     listwatch_T	fi_lw;		// keep an eye on the item used.
41     list_T	*fi_list;	// list being used
42     int		fi_bi;		// index of blob
43     blob_T	*fi_blob;	// blob being used
44 } forinfo_T;
45 
46 static int tv_op(typval_T *tv1, typval_T *tv2, char_u  *op);
47 static int eval2(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
48 static int eval3(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
49 static int eval4(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
50 static int eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
51 static int eval6(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
52 static int eval7(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
53 static int eval7_leader(typval_T *rettv, int numeric_only, char_u *start_leader, char_u **end_leaderp);
54 
55 static int free_unref_items(int copyID);
56 static char_u *make_expanded_name(char_u *in_start, char_u *expr_start, char_u *expr_end, char_u *in_end);
57 
58 /*
59  * Return "n1" divided by "n2", taking care of dividing by zero.
60  */
61 	varnumber_T
62 num_divide(varnumber_T n1, varnumber_T n2)
63 {
64     varnumber_T	result;
65 
66     if (n2 == 0)	// give an error message?
67     {
68 	if (n1 == 0)
69 	    result = VARNUM_MIN; // similar to NaN
70 	else if (n1 < 0)
71 	    result = -VARNUM_MAX;
72 	else
73 	    result = VARNUM_MAX;
74     }
75     else
76 	result = n1 / n2;
77 
78     return result;
79 }
80 
81 /*
82  * Return "n1" modulus "n2", taking care of dividing by zero.
83  */
84 	varnumber_T
85 num_modulus(varnumber_T n1, varnumber_T n2)
86 {
87     // Give an error when n2 is 0?
88     return (n2 == 0) ? 0 : (n1 % n2);
89 }
90 
91 #if defined(EBCDIC) || defined(PROTO)
92 /*
93  * Compare struct fst by function name.
94  */
95     static int
96 compare_func_name(const void *s1, const void *s2)
97 {
98     struct fst *p1 = (struct fst *)s1;
99     struct fst *p2 = (struct fst *)s2;
100 
101     return STRCMP(p1->f_name, p2->f_name);
102 }
103 
104 /*
105  * Sort the function table by function name.
106  * The sorting of the table above is ASCII dependent.
107  * On machines using EBCDIC we have to sort it.
108  */
109     static void
110 sortFunctions(void)
111 {
112     int		funcCnt = (int)(sizeof(functions) / sizeof(struct fst)) - 1;
113 
114     qsort(functions, (size_t)funcCnt, sizeof(struct fst), compare_func_name);
115 }
116 #endif
117 
118 /*
119  * Initialize the global and v: variables.
120  */
121     void
122 eval_init(void)
123 {
124     evalvars_init();
125     func_init();
126 
127 #ifdef EBCDIC
128     /*
129      * Sort the function table, to enable binary search.
130      */
131     sortFunctions();
132 #endif
133 }
134 
135 #if defined(EXITFREE) || defined(PROTO)
136     void
137 eval_clear(void)
138 {
139     evalvars_clear();
140     free_scriptnames();  // must come after evalvars_clear().
141     free_locales();
142 
143     // autoloaded script names
144     free_autoload_scriptnames();
145 
146     // unreferenced lists and dicts
147     (void)garbage_collect(FALSE);
148 
149     // functions not garbage collected
150     free_all_functions();
151 }
152 #endif
153 
154     void
155 fill_evalarg_from_eap(evalarg_T *evalarg, exarg_T *eap, int skip)
156 {
157     CLEAR_FIELD(*evalarg);
158     evalarg->eval_flags = skip ? 0 : EVAL_EVALUATE;
159     if (eap != NULL && getline_equal(eap->getline, eap->cookie, getsourceline))
160     {
161 	evalarg->eval_getline = eap->getline;
162 	evalarg->eval_cookie = eap->cookie;
163     }
164 }
165 
166 /*
167  * Top level evaluation function, returning a boolean.
168  * Sets "error" to TRUE if there was an error.
169  * Return TRUE or FALSE.
170  */
171     int
172 eval_to_bool(
173     char_u	*arg,
174     int		*error,
175     exarg_T	*eap,
176     int		skip)	    // only parse, don't execute
177 {
178     typval_T	tv;
179     varnumber_T	retval = FALSE;
180     evalarg_T	evalarg;
181 
182     fill_evalarg_from_eap(&evalarg, eap, skip);
183 
184     if (skip)
185 	++emsg_skip;
186     if (eval0(arg, &tv, eap, &evalarg) == FAIL)
187 	*error = TRUE;
188     else
189     {
190 	*error = FALSE;
191 	if (!skip)
192 	{
193 	    if (in_vim9script())
194 		retval = tv_get_bool_chk(&tv, error);
195 	    else
196 		retval = (tv_get_number_chk(&tv, error) != 0);
197 	    clear_tv(&tv);
198 	}
199     }
200     if (skip)
201 	--emsg_skip;
202     clear_evalarg(&evalarg, eap);
203 
204     return (int)retval;
205 }
206 
207 /*
208  * Call eval1() and give an error message if not done at a lower level.
209  */
210     static int
211 eval1_emsg(char_u **arg, typval_T *rettv, exarg_T *eap)
212 {
213     char_u	*start = *arg;
214     int		ret;
215     int		did_emsg_before = did_emsg;
216     int		called_emsg_before = called_emsg;
217     evalarg_T	evalarg;
218 
219     fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);
220 
221     ret = eval1(arg, rettv, &evalarg);
222     if (ret == FAIL)
223     {
224 	// Report the invalid expression unless the expression evaluation has
225 	// been cancelled due to an aborting error, an interrupt, or an
226 	// exception, or we already gave a more specific error.
227 	// Also check called_emsg for when using assert_fails().
228 	if (!aborting() && did_emsg == did_emsg_before
229 					  && called_emsg == called_emsg_before)
230 	    semsg(_(e_invexpr2), start);
231     }
232     clear_evalarg(&evalarg, eap);
233     return ret;
234 }
235 
236 /*
237  * Return whether a typval is a valid expression to pass to eval_expr_typval()
238  * or eval_expr_to_bool().  An empty string returns FALSE;
239  */
240     int
241 eval_expr_valid_arg(typval_T *tv)
242 {
243     return tv->v_type != VAR_UNKNOWN
244 	    && (tv->v_type != VAR_STRING
245 		  || (tv->vval.v_string != NULL && *tv->vval.v_string != NUL));
246 }
247 
248 /*
249  * Evaluate an expression, which can be a function, partial or string.
250  * Pass arguments "argv[argc]".
251  * Return the result in "rettv" and OK or FAIL.
252  */
253     int
254 eval_expr_typval(typval_T *expr, typval_T *argv, int argc, typval_T *rettv)
255 {
256     char_u	*s;
257     char_u	buf[NUMBUFLEN];
258     funcexe_T	funcexe;
259 
260     if (expr->v_type == VAR_FUNC)
261     {
262 	s = expr->vval.v_string;
263 	if (s == NULL || *s == NUL)
264 	    return FAIL;
265 	CLEAR_FIELD(funcexe);
266 	funcexe.evaluate = TRUE;
267 	if (call_func(s, -1, rettv, argc, argv, &funcexe) == FAIL)
268 	    return FAIL;
269     }
270     else if (expr->v_type == VAR_PARTIAL)
271     {
272 	partial_T   *partial = expr->vval.v_partial;
273 
274 	if (partial == NULL)
275 	    return FAIL;
276 
277 	if (partial->pt_func != NULL
278 			  && partial->pt_func->uf_def_status != UF_NOT_COMPILED)
279 	{
280 	    if (call_def_function(partial->pt_func, argc, argv,
281 						       partial, rettv) == FAIL)
282 		return FAIL;
283 	}
284 	else
285 	{
286 	    s = partial_name(partial);
287 	    if (s == NULL || *s == NUL)
288 		return FAIL;
289 	    CLEAR_FIELD(funcexe);
290 	    funcexe.evaluate = TRUE;
291 	    funcexe.partial = partial;
292 	    if (call_func(s, -1, rettv, argc, argv, &funcexe) == FAIL)
293 		return FAIL;
294 	}
295     }
296     else
297     {
298 	s = tv_get_string_buf_chk(expr, buf);
299 	if (s == NULL)
300 	    return FAIL;
301 	s = skipwhite(s);
302 	if (eval1_emsg(&s, rettv, NULL) == FAIL)
303 	    return FAIL;
304 	if (*skipwhite(s) != NUL)  // check for trailing chars after expr
305 	{
306 	    clear_tv(rettv);
307 	    semsg(_(e_invexpr2), s);
308 	    return FAIL;
309 	}
310     }
311     return OK;
312 }
313 
314 /*
315  * Like eval_to_bool() but using a typval_T instead of a string.
316  * Works for string, funcref and partial.
317  */
318     int
319 eval_expr_to_bool(typval_T *expr, int *error)
320 {
321     typval_T	rettv;
322     int		res;
323 
324     if (eval_expr_typval(expr, NULL, 0, &rettv) == FAIL)
325     {
326 	*error = TRUE;
327 	return FALSE;
328     }
329     res = (tv_get_bool_chk(&rettv, error) != 0);
330     clear_tv(&rettv);
331     return res;
332 }
333 
334 /*
335  * Top level evaluation function, returning a string.  If "skip" is TRUE,
336  * only parsing to "nextcmd" is done, without reporting errors.  Return
337  * pointer to allocated memory, or NULL for failure or when "skip" is TRUE.
338  */
339     char_u *
340 eval_to_string_skip(
341     char_u	*arg,
342     exarg_T	*eap,
343     int		skip)	    // only parse, don't execute
344 {
345     typval_T	tv;
346     char_u	*retval;
347     evalarg_T	evalarg;
348 
349     fill_evalarg_from_eap(&evalarg, eap, skip);
350     if (skip)
351 	++emsg_skip;
352     if (eval0(arg, &tv, eap, &evalarg) == FAIL || skip)
353 	retval = NULL;
354     else
355     {
356 	retval = vim_strsave(tv_get_string(&tv));
357 	clear_tv(&tv);
358     }
359     if (skip)
360 	--emsg_skip;
361     clear_evalarg(&evalarg, eap);
362 
363     return retval;
364 }
365 
366 /*
367  * Skip over an expression at "*pp".
368  * Return FAIL for an error, OK otherwise.
369  */
370     int
371 skip_expr(char_u **pp, evalarg_T *evalarg)
372 {
373     typval_T	rettv;
374 
375     *pp = skipwhite(*pp);
376     return eval1(pp, &rettv, evalarg);
377 }
378 
379 /*
380  * Skip over an expression at "*pp".
381  * If in Vim9 script and line breaks are encountered, the lines are
382  * concatenated.  "evalarg->eval_tofree" will be set accordingly.
383  * "arg" is advanced to just after the expression.
384  * "start" is set to the start of the expression, "end" to just after the end.
385  * Also when the expression is copied to allocated memory.
386  * Return FAIL for an error, OK otherwise.
387  */
388     int
389 skip_expr_concatenate(
390 	char_u	    **arg,
391 	char_u	    **start,
392 	char_u	    **end,
393 	evalarg_T   *evalarg)
394 {
395     typval_T	rettv;
396     int		res;
397     int		vim9script = in_vim9script();
398     garray_T    *gap = evalarg == NULL ? NULL : &evalarg->eval_ga;
399     int		save_flags = evalarg == NULL ? 0 : evalarg->eval_flags;
400     int		evaluate = evalarg == NULL
401 			       ? FALSE : (evalarg->eval_flags & EVAL_EVALUATE);
402 
403     if (vim9script && evaluate
404 	       && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL))
405     {
406 	ga_init2(gap, sizeof(char_u *), 10);
407 	// leave room for "start"
408 	if (ga_grow(gap, 1) == OK)
409 	    ++gap->ga_len;
410     }
411     *start = *arg;
412 
413     // Don't evaluate the expression.
414     if (evalarg != NULL)
415 	evalarg->eval_flags &= ~EVAL_EVALUATE;
416     *arg = skipwhite(*arg);
417     res = eval1(arg, &rettv, evalarg);
418     *end = *arg;
419     if (evalarg != NULL)
420 	evalarg->eval_flags = save_flags;
421 
422     if (vim9script && evaluate
423 	    && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL))
424     {
425 	if (evalarg->eval_ga.ga_len == 1)
426 	{
427 	    // just one line, no need to concatenate
428 	    ga_clear(gap);
429 	    gap->ga_itemsize = 0;
430 	}
431 	else
432 	{
433 	    char_u	    *p;
434 	    size_t	    endoff = STRLEN(*arg);
435 
436 	    // Line breaks encountered, concatenate all the lines.
437 	    *((char_u **)gap->ga_data) = *start;
438 	    p = ga_concat_strings(gap, "");
439 
440 	    // free the lines only when using getsourceline()
441 	    if (evalarg->eval_cookie != NULL)
442 	    {
443 		// Do not free the first line, the caller can still use it.
444 		*((char_u **)gap->ga_data) = NULL;
445 		// Do not free the last line, "arg" points into it, free it
446 		// later.
447 		vim_free(evalarg->eval_tofree);
448 		evalarg->eval_tofree =
449 				    ((char_u **)gap->ga_data)[gap->ga_len - 1];
450 		((char_u **)gap->ga_data)[gap->ga_len - 1] = NULL;
451 		ga_clear_strings(gap);
452 	    }
453 	    else
454 		ga_clear(gap);
455 	    gap->ga_itemsize = 0;
456 	    if (p == NULL)
457 		return FAIL;
458 	    *start = p;
459 	    vim_free(evalarg->eval_tofree_lambda);
460 	    evalarg->eval_tofree_lambda = p;
461 	    // Compute "end" relative to the end.
462 	    *end = *start + STRLEN(*start) - endoff;
463 	}
464     }
465 
466     return res;
467 }
468 
469 /*
470  * Top level evaluation function, returning a string.  Does not handle line
471  * breaks.
472  * When "convert" is TRUE convert a List into a sequence of lines and convert
473  * a Float to a String.
474  * Return pointer to allocated memory, or NULL for failure.
475  */
476     char_u *
477 eval_to_string(
478     char_u	*arg,
479     int		convert)
480 {
481     typval_T	tv;
482     char_u	*retval;
483     garray_T	ga;
484 #ifdef FEAT_FLOAT
485     char_u	numbuf[NUMBUFLEN];
486 #endif
487 
488     if (eval0(arg, &tv, NULL, &EVALARG_EVALUATE) == FAIL)
489 	retval = NULL;
490     else
491     {
492 	if (convert && tv.v_type == VAR_LIST)
493 	{
494 	    ga_init2(&ga, (int)sizeof(char), 80);
495 	    if (tv.vval.v_list != NULL)
496 	    {
497 		list_join(&ga, tv.vval.v_list, (char_u *)"\n", TRUE, FALSE, 0);
498 		if (tv.vval.v_list->lv_len > 0)
499 		    ga_append(&ga, NL);
500 	    }
501 	    ga_append(&ga, NUL);
502 	    retval = (char_u *)ga.ga_data;
503 	}
504 #ifdef FEAT_FLOAT
505 	else if (convert && tv.v_type == VAR_FLOAT)
506 	{
507 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv.vval.v_float);
508 	    retval = vim_strsave(numbuf);
509 	}
510 #endif
511 	else
512 	    retval = vim_strsave(tv_get_string(&tv));
513 	clear_tv(&tv);
514     }
515     clear_evalarg(&EVALARG_EVALUATE, NULL);
516 
517     return retval;
518 }
519 
520 /*
521  * Call eval_to_string() without using current local variables and using
522  * textwinlock.  When "use_sandbox" is TRUE use the sandbox.
523  * Use legacy Vim script syntax.
524  */
525     char_u *
526 eval_to_string_safe(
527     char_u	*arg,
528     int		use_sandbox)
529 {
530     char_u	*retval;
531     funccal_entry_T funccal_entry;
532     int		save_sc_version = current_sctx.sc_version;
533 
534     current_sctx.sc_version = 1;
535     save_funccal(&funccal_entry);
536     if (use_sandbox)
537 	++sandbox;
538     ++textwinlock;
539     retval = eval_to_string(arg, FALSE);
540     if (use_sandbox)
541 	--sandbox;
542     --textwinlock;
543     restore_funccal();
544     current_sctx.sc_version = save_sc_version;
545     return retval;
546 }
547 
548 /*
549  * Top level evaluation function, returning a number.
550  * Evaluates "expr" silently.
551  * Returns -1 for an error.
552  */
553     varnumber_T
554 eval_to_number(char_u *expr)
555 {
556     typval_T	rettv;
557     varnumber_T	retval;
558     char_u	*p = skipwhite(expr);
559 
560     ++emsg_off;
561 
562     if (eval1(&p, &rettv, &EVALARG_EVALUATE) == FAIL)
563 	retval = -1;
564     else
565     {
566 	retval = tv_get_number_chk(&rettv, NULL);
567 	clear_tv(&rettv);
568     }
569     --emsg_off;
570 
571     return retval;
572 }
573 
574 /*
575  * Top level evaluation function.
576  * Returns an allocated typval_T with the result.
577  * Returns NULL when there is an error.
578  */
579     typval_T *
580 eval_expr(char_u *arg, exarg_T *eap)
581 {
582     typval_T	*tv;
583     evalarg_T	evalarg;
584 
585     fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);
586 
587     tv = ALLOC_ONE(typval_T);
588     if (tv != NULL && eval0(arg, tv, eap, &evalarg) == FAIL)
589 	VIM_CLEAR(tv);
590 
591     clear_evalarg(&evalarg, eap);
592     return tv;
593 }
594 
595 /*
596  * Call some Vim script function and return the result in "*rettv".
597  * Uses argv[0] to argv[argc - 1] for the function arguments.  argv[argc]
598  * should have type VAR_UNKNOWN.
599  * Returns OK or FAIL.
600  */
601     int
602 call_vim_function(
603     char_u      *func,
604     int		argc,
605     typval_T	*argv,
606     typval_T	*rettv)
607 {
608     int		ret;
609     funcexe_T	funcexe;
610 
611     rettv->v_type = VAR_UNKNOWN;		// clear_tv() uses this
612     CLEAR_FIELD(funcexe);
613     funcexe.firstline = curwin->w_cursor.lnum;
614     funcexe.lastline = curwin->w_cursor.lnum;
615     funcexe.evaluate = TRUE;
616     ret = call_func(func, -1, rettv, argc, argv, &funcexe);
617     if (ret == FAIL)
618 	clear_tv(rettv);
619 
620     return ret;
621 }
622 
623 /*
624  * Call Vim script function "func" and return the result as a number.
625  * Returns -1 when calling the function fails.
626  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
627  * have type VAR_UNKNOWN.
628  */
629     varnumber_T
630 call_func_retnr(
631     char_u      *func,
632     int		argc,
633     typval_T	*argv)
634 {
635     typval_T	rettv;
636     varnumber_T	retval;
637 
638     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
639 	return -1;
640 
641     retval = tv_get_number_chk(&rettv, NULL);
642     clear_tv(&rettv);
643     return retval;
644 }
645 
646 /*
647  * Call Vim script function "func" and return the result as a string.
648  * Returns NULL when calling the function fails.
649  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
650  * have type VAR_UNKNOWN.
651  */
652     void *
653 call_func_retstr(
654     char_u      *func,
655     int		argc,
656     typval_T	*argv)
657 {
658     typval_T	rettv;
659     char_u	*retval;
660 
661     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
662 	return NULL;
663 
664     retval = vim_strsave(tv_get_string(&rettv));
665     clear_tv(&rettv);
666     return retval;
667 }
668 
669 /*
670  * Call Vim script function "func" and return the result as a List.
671  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
672  * have type VAR_UNKNOWN.
673  * Returns NULL when there is something wrong.
674  */
675     void *
676 call_func_retlist(
677     char_u      *func,
678     int		argc,
679     typval_T	*argv)
680 {
681     typval_T	rettv;
682 
683     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
684 	return NULL;
685 
686     if (rettv.v_type != VAR_LIST)
687     {
688 	clear_tv(&rettv);
689 	return NULL;
690     }
691 
692     return rettv.vval.v_list;
693 }
694 
695 #ifdef FEAT_FOLDING
696 /*
697  * Evaluate 'foldexpr'.  Returns the foldlevel, and any character preceding
698  * it in "*cp".  Doesn't give error messages.
699  */
700     int
701 eval_foldexpr(char_u *arg, int *cp)
702 {
703     typval_T	tv;
704     varnumber_T	retval;
705     char_u	*s;
706     int		use_sandbox = was_set_insecurely((char_u *)"foldexpr",
707 								   OPT_LOCAL);
708 
709     ++emsg_off;
710     if (use_sandbox)
711 	++sandbox;
712     ++textwinlock;
713     *cp = NUL;
714     if (eval0(arg, &tv, NULL, &EVALARG_EVALUATE) == FAIL)
715 	retval = 0;
716     else
717     {
718 	// If the result is a number, just return the number.
719 	if (tv.v_type == VAR_NUMBER)
720 	    retval = tv.vval.v_number;
721 	else if (tv.v_type != VAR_STRING || tv.vval.v_string == NULL)
722 	    retval = 0;
723 	else
724 	{
725 	    // If the result is a string, check if there is a non-digit before
726 	    // the number.
727 	    s = tv.vval.v_string;
728 	    if (!VIM_ISDIGIT(*s) && *s != '-')
729 		*cp = *s++;
730 	    retval = atol((char *)s);
731 	}
732 	clear_tv(&tv);
733     }
734     --emsg_off;
735     if (use_sandbox)
736 	--sandbox;
737     --textwinlock;
738     clear_evalarg(&EVALARG_EVALUATE, NULL);
739 
740     return (int)retval;
741 }
742 #endif
743 
744 /*
745  * Get an lval: variable, Dict item or List item that can be assigned a value
746  * to: "name", "na{me}", "name[expr]", "name[expr:expr]", "name[expr][expr]",
747  * "name.key", "name.key[expr]" etc.
748  * Indexing only works if "name" is an existing List or Dictionary.
749  * "name" points to the start of the name.
750  * If "rettv" is not NULL it points to the value to be assigned.
751  * "unlet" is TRUE for ":unlet": slightly different behavior when something is
752  * wrong; must end in space or cmd separator.
753  *
754  * flags:
755  *  GLV_QUIET:       do not give error messages
756  *  GLV_READ_ONLY:   will not change the variable
757  *  GLV_NO_AUTOLOAD: do not use script autoloading
758  *
759  * Returns a pointer to just after the name, including indexes.
760  * When an evaluation error occurs "lp->ll_name" is NULL;
761  * Returns NULL for a parsing error.  Still need to free items in "lp"!
762  */
763     char_u *
764 get_lval(
765     char_u	*name,
766     typval_T	*rettv,
767     lval_T	*lp,
768     int		unlet,
769     int		skip,
770     int		flags,	    // GLV_ values
771     int		fne_flags)  // flags for find_name_end()
772 {
773     char_u	*p;
774     char_u	*expr_start, *expr_end;
775     int		cc;
776     dictitem_T	*v;
777     typval_T	var1;
778     typval_T	var2;
779     int		empty1 = FALSE;
780     listitem_T	*ni;
781     char_u	*key = NULL;
782     int		len;
783     hashtab_T	*ht;
784     int		quiet = flags & GLV_QUIET;
785 
786     // Clear everything in "lp".
787     CLEAR_POINTER(lp);
788 
789     if (skip)
790     {
791 	// When skipping just find the end of the name.
792 	lp->ll_name = name;
793 	lp->ll_name_end = find_name_end(name, NULL, NULL,
794 						      FNE_INCL_BR | fne_flags);
795 	return lp->ll_name_end;
796     }
797 
798     // Find the end of the name.
799     p = find_name_end(name, &expr_start, &expr_end, fne_flags);
800     lp->ll_name_end = p;
801     if (expr_start != NULL)
802     {
803 	// Don't expand the name when we already know there is an error.
804 	if (unlet && !VIM_ISWHITE(*p) && !ends_excmd(*p)
805 						    && *p != '[' && *p != '.')
806 	{
807 	    semsg(_(e_trailing_arg), p);
808 	    return NULL;
809 	}
810 
811 	lp->ll_exp_name = make_expanded_name(name, expr_start, expr_end, p);
812 	if (lp->ll_exp_name == NULL)
813 	{
814 	    // Report an invalid expression in braces, unless the
815 	    // expression evaluation has been cancelled due to an
816 	    // aborting error, an interrupt, or an exception.
817 	    if (!aborting() && !quiet)
818 	    {
819 		emsg_severe = TRUE;
820 		semsg(_(e_invarg2), name);
821 		return NULL;
822 	    }
823 	}
824 	lp->ll_name = lp->ll_exp_name;
825     }
826     else
827     {
828 	lp->ll_name = name;
829 
830 	if (in_vim9script())
831 	{
832 	    // "a: type" is declaring variable "a" with a type, not "a:".
833 	    if (p == name + 2 && p[-1] == ':')
834 	    {
835 		--p;
836 		lp->ll_name_end = p;
837 	    }
838 	    if (*p == ':')
839 	    {
840 		scriptitem_T *si = SCRIPT_ITEM(current_sctx.sc_sid);
841 		char_u	 *tp = skipwhite(p + 1);
842 
843 		// parse the type after the name
844 		lp->ll_type = parse_type(&tp, &si->sn_type_list);
845 		lp->ll_name_end = tp;
846 	    }
847 	}
848     }
849 
850     // Without [idx] or .key we are done.
851     if ((*p != '[' && *p != '.') || lp->ll_name == NULL)
852 	return p;
853 
854     cc = *p;
855     *p = NUL;
856     // Only pass &ht when we would write to the variable, it prevents autoload
857     // as well.
858     v = find_var(lp->ll_name, (flags & GLV_READ_ONLY) ? NULL : &ht,
859 						      flags & GLV_NO_AUTOLOAD);
860     if (v == NULL && !quiet)
861 	semsg(_(e_undefined_variable_str), lp->ll_name);
862     *p = cc;
863     if (v == NULL)
864 	return NULL;
865 
866     /*
867      * Loop until no more [idx] or .key is following.
868      */
869     lp->ll_tv = &v->di_tv;
870     var1.v_type = VAR_UNKNOWN;
871     var2.v_type = VAR_UNKNOWN;
872     while (*p == '[' || (*p == '.' && lp->ll_tv->v_type == VAR_DICT))
873     {
874 	if (!(lp->ll_tv->v_type == VAR_LIST && lp->ll_tv->vval.v_list != NULL)
875 		&& !(lp->ll_tv->v_type == VAR_DICT)
876 		&& !(lp->ll_tv->v_type == VAR_BLOB
877 					   && lp->ll_tv->vval.v_blob != NULL))
878 	{
879 	    if (!quiet)
880 		emsg(_("E689: Can only index a List, Dictionary or Blob"));
881 	    return NULL;
882 	}
883 	if (lp->ll_range)
884 	{
885 	    if (!quiet)
886 		emsg(_("E708: [:] must come last"));
887 	    return NULL;
888 	}
889 
890 	if (in_vim9script() && lp->ll_valtype == NULL
891 		&& lp->ll_tv == &v->di_tv
892 		&& ht != NULL && ht == get_script_local_ht())
893 	{
894 	    svar_T  *sv = find_typval_in_script(lp->ll_tv);
895 
896 	    // Vim9 script local variable: get the type
897 	    if (sv != NULL)
898 		lp->ll_valtype = sv->sv_type;
899 	}
900 
901 	len = -1;
902 	if (*p == '.')
903 	{
904 	    key = p + 1;
905 	    for (len = 0; ASCII_ISALNUM(key[len]) || key[len] == '_'; ++len)
906 		;
907 	    if (len == 0)
908 	    {
909 		if (!quiet)
910 		    emsg(_(e_emptykey));
911 		return NULL;
912 	    }
913 	    p = key + len;
914 	}
915 	else
916 	{
917 	    // Get the index [expr] or the first index [expr: ].
918 	    p = skipwhite(p + 1);
919 	    if (*p == ':')
920 		empty1 = TRUE;
921 	    else
922 	    {
923 		empty1 = FALSE;
924 		if (eval1(&p, &var1, &EVALARG_EVALUATE) == FAIL)  // recursive!
925 		    return NULL;
926 		if (tv_get_string_chk(&var1) == NULL)
927 		{
928 		    // not a number or string
929 		    clear_tv(&var1);
930 		    return NULL;
931 		}
932 		p = skipwhite(p);
933 	    }
934 
935 	    // Optionally get the second index [ :expr].
936 	    if (*p == ':')
937 	    {
938 		if (lp->ll_tv->v_type == VAR_DICT)
939 		{
940 		    if (!quiet)
941 			emsg(_(e_cannot_slice_dictionary));
942 		    clear_tv(&var1);
943 		    return NULL;
944 		}
945 		if (rettv != NULL
946 			&& !(rettv->v_type == VAR_LIST
947 						 && rettv->vval.v_list != NULL)
948 			&& !(rettv->v_type == VAR_BLOB
949 						&& rettv->vval.v_blob != NULL))
950 		{
951 		    if (!quiet)
952 			emsg(_("E709: [:] requires a List or Blob value"));
953 		    clear_tv(&var1);
954 		    return NULL;
955 		}
956 		p = skipwhite(p + 1);
957 		if (*p == ']')
958 		    lp->ll_empty2 = TRUE;
959 		else
960 		{
961 		    lp->ll_empty2 = FALSE;
962 		    // recursive!
963 		    if (eval1(&p, &var2, &EVALARG_EVALUATE) == FAIL)
964 		    {
965 			clear_tv(&var1);
966 			return NULL;
967 		    }
968 		    if (tv_get_string_chk(&var2) == NULL)
969 		    {
970 			// not a number or string
971 			clear_tv(&var1);
972 			clear_tv(&var2);
973 			return NULL;
974 		    }
975 		}
976 		lp->ll_range = TRUE;
977 	    }
978 	    else
979 		lp->ll_range = FALSE;
980 
981 	    if (*p != ']')
982 	    {
983 		if (!quiet)
984 		    emsg(_(e_missbrac));
985 		clear_tv(&var1);
986 		clear_tv(&var2);
987 		return NULL;
988 	    }
989 
990 	    // Skip to past ']'.
991 	    ++p;
992 	}
993 
994 	if (lp->ll_tv->v_type == VAR_DICT)
995 	{
996 	    if (len == -1)
997 	    {
998 		// "[key]": get key from "var1"
999 		key = tv_get_string_chk(&var1);	// is number or string
1000 		if (key == NULL)
1001 		{
1002 		    clear_tv(&var1);
1003 		    return NULL;
1004 		}
1005 	    }
1006 	    lp->ll_list = NULL;
1007 
1008 	    // a NULL dict is equivalent with an empty dict
1009 	    if (lp->ll_tv->vval.v_dict == NULL)
1010 	    {
1011 		lp->ll_tv->vval.v_dict = dict_alloc();
1012 		if (lp->ll_tv->vval.v_dict == NULL)
1013 		{
1014 		    clear_tv(&var1);
1015 		    return NULL;
1016 		}
1017 		++lp->ll_tv->vval.v_dict->dv_refcount;
1018 	    }
1019 	    lp->ll_dict = lp->ll_tv->vval.v_dict;
1020 
1021 	    lp->ll_di = dict_find(lp->ll_dict, key, len);
1022 
1023 	    // When assigning to a scope dictionary check that a function and
1024 	    // variable name is valid (only variable name unless it is l: or
1025 	    // g: dictionary). Disallow overwriting a builtin function.
1026 	    if (rettv != NULL && lp->ll_dict->dv_scope != 0)
1027 	    {
1028 		int prevval;
1029 		int wrong;
1030 
1031 		if (len != -1)
1032 		{
1033 		    prevval = key[len];
1034 		    key[len] = NUL;
1035 		}
1036 		else
1037 		    prevval = 0; // avoid compiler warning
1038 		wrong = (lp->ll_dict->dv_scope == VAR_DEF_SCOPE
1039 			       && rettv->v_type == VAR_FUNC
1040 			       && var_wrong_func_name(key, lp->ll_di == NULL))
1041 			|| !valid_varname(key);
1042 		if (len != -1)
1043 		    key[len] = prevval;
1044 		if (wrong)
1045 		{
1046 		    clear_tv(&var1);
1047 		    return NULL;
1048 		}
1049 	    }
1050 
1051 	    if (lp->ll_valtype != NULL)
1052 		// use the type of the member
1053 		lp->ll_valtype = lp->ll_valtype->tt_member;
1054 
1055 	    if (lp->ll_di == NULL)
1056 	    {
1057 		// Can't add "v:" or "a:" variable.
1058 		if (lp->ll_dict == get_vimvar_dict()
1059 			 || &lp->ll_dict->dv_hashtab == get_funccal_args_ht())
1060 		{
1061 		    semsg(_(e_illvar), name);
1062 		    clear_tv(&var1);
1063 		    return NULL;
1064 		}
1065 
1066 		// Key does not exist in dict: may need to add it.
1067 		if (*p == '[' || *p == '.' || unlet)
1068 		{
1069 		    if (!quiet)
1070 			semsg(_(e_dictkey), key);
1071 		    clear_tv(&var1);
1072 		    return NULL;
1073 		}
1074 		if (len == -1)
1075 		    lp->ll_newkey = vim_strsave(key);
1076 		else
1077 		    lp->ll_newkey = vim_strnsave(key, len);
1078 		clear_tv(&var1);
1079 		if (lp->ll_newkey == NULL)
1080 		    p = NULL;
1081 		break;
1082 	    }
1083 	    // existing variable, need to check if it can be changed
1084 	    else if ((flags & GLV_READ_ONLY) == 0
1085 			&& (var_check_ro(lp->ll_di->di_flags, name, FALSE)
1086 			  || var_check_lock(lp->ll_di->di_flags, name, FALSE)))
1087 	    {
1088 		clear_tv(&var1);
1089 		return NULL;
1090 	    }
1091 
1092 	    clear_tv(&var1);
1093 	    lp->ll_tv = &lp->ll_di->di_tv;
1094 	}
1095 	else if (lp->ll_tv->v_type == VAR_BLOB)
1096 	{
1097 	    long bloblen = blob_len(lp->ll_tv->vval.v_blob);
1098 
1099 	    /*
1100 	     * Get the number and item for the only or first index of the List.
1101 	     */
1102 	    if (empty1)
1103 		lp->ll_n1 = 0;
1104 	    else
1105 		// is number or string
1106 		lp->ll_n1 = (long)tv_get_number(&var1);
1107 	    clear_tv(&var1);
1108 
1109 	    if (lp->ll_n1 < 0
1110 		    || lp->ll_n1 > bloblen
1111 		    || (lp->ll_range && lp->ll_n1 == bloblen))
1112 	    {
1113 		if (!quiet)
1114 		    semsg(_(e_blobidx), lp->ll_n1);
1115 		clear_tv(&var2);
1116 		return NULL;
1117 	    }
1118 	    if (lp->ll_range && !lp->ll_empty2)
1119 	    {
1120 		lp->ll_n2 = (long)tv_get_number(&var2);
1121 		clear_tv(&var2);
1122 		if (lp->ll_n2 < 0
1123 			|| lp->ll_n2 >= bloblen
1124 			|| lp->ll_n2 < lp->ll_n1)
1125 		{
1126 		    if (!quiet)
1127 			semsg(_(e_blobidx), lp->ll_n2);
1128 		    return NULL;
1129 		}
1130 	    }
1131 	    lp->ll_blob = lp->ll_tv->vval.v_blob;
1132 	    lp->ll_tv = NULL;
1133 	    break;
1134 	}
1135 	else
1136 	{
1137 	    /*
1138 	     * Get the number and item for the only or first index of the List.
1139 	     */
1140 	    if (empty1)
1141 		lp->ll_n1 = 0;
1142 	    else
1143 		// is number or string
1144 		lp->ll_n1 = (long)tv_get_number(&var1);
1145 	    clear_tv(&var1);
1146 
1147 	    lp->ll_dict = NULL;
1148 	    lp->ll_list = lp->ll_tv->vval.v_list;
1149 	    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
1150 	    if (lp->ll_li == NULL)
1151 	    {
1152 		if (lp->ll_n1 < 0)
1153 		{
1154 		    lp->ll_n1 = 0;
1155 		    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
1156 		}
1157 	    }
1158 	    if (lp->ll_li == NULL)
1159 	    {
1160 		clear_tv(&var2);
1161 		if (!quiet)
1162 		    semsg(_(e_listidx), lp->ll_n1);
1163 		return NULL;
1164 	    }
1165 
1166 	    if (lp->ll_valtype != NULL)
1167 		// use the type of the member
1168 		lp->ll_valtype = lp->ll_valtype->tt_member;
1169 
1170 	    /*
1171 	     * May need to find the item or absolute index for the second
1172 	     * index of a range.
1173 	     * When no index given: "lp->ll_empty2" is TRUE.
1174 	     * Otherwise "lp->ll_n2" is set to the second index.
1175 	     */
1176 	    if (lp->ll_range && !lp->ll_empty2)
1177 	    {
1178 		lp->ll_n2 = (long)tv_get_number(&var2);
1179 						    // is number or string
1180 		clear_tv(&var2);
1181 		if (lp->ll_n2 < 0)
1182 		{
1183 		    ni = list_find(lp->ll_list, lp->ll_n2);
1184 		    if (ni == NULL)
1185 		    {
1186 			if (!quiet)
1187 			    semsg(_(e_listidx), lp->ll_n2);
1188 			return NULL;
1189 		    }
1190 		    lp->ll_n2 = list_idx_of_item(lp->ll_list, ni);
1191 		}
1192 
1193 		// Check that lp->ll_n2 isn't before lp->ll_n1.
1194 		if (lp->ll_n1 < 0)
1195 		    lp->ll_n1 = list_idx_of_item(lp->ll_list, lp->ll_li);
1196 		if (lp->ll_n2 < lp->ll_n1)
1197 		{
1198 		    if (!quiet)
1199 			semsg(_(e_listidx), lp->ll_n2);
1200 		    return NULL;
1201 		}
1202 	    }
1203 
1204 	    lp->ll_tv = &lp->ll_li->li_tv;
1205 	}
1206     }
1207 
1208     clear_tv(&var1);
1209     lp->ll_name_end = p;
1210     return p;
1211 }
1212 
1213 /*
1214  * Clear lval "lp" that was filled by get_lval().
1215  */
1216     void
1217 clear_lval(lval_T *lp)
1218 {
1219     vim_free(lp->ll_exp_name);
1220     vim_free(lp->ll_newkey);
1221 }
1222 
1223 /*
1224  * Set a variable that was parsed by get_lval() to "rettv".
1225  * "endp" points to just after the parsed name.
1226  * "op" is NULL, "+" for "+=", "-" for "-=", "*" for "*=", "/" for "/=",
1227  * "%" for "%=", "." for ".=" or "=" for "=".
1228  */
1229     void
1230 set_var_lval(
1231     lval_T	*lp,
1232     char_u	*endp,
1233     typval_T	*rettv,
1234     int		copy,
1235     int		flags,    // ASSIGN_CONST, ASSIGN_NO_DECL
1236     char_u	*op)
1237 {
1238     int		cc;
1239     listitem_T	*ri;
1240     dictitem_T	*di;
1241 
1242     if (lp->ll_tv == NULL)
1243     {
1244 	cc = *endp;
1245 	*endp = NUL;
1246 	if (lp->ll_blob != NULL)
1247 	{
1248 	    int	    error = FALSE, val;
1249 
1250 	    if (op != NULL && *op != '=')
1251 	    {
1252 		semsg(_(e_letwrong), op);
1253 		return;
1254 	    }
1255 	    if (value_check_lock(lp->ll_blob->bv_lock, lp->ll_name, FALSE))
1256 		return;
1257 
1258 	    if (lp->ll_range && rettv->v_type == VAR_BLOB)
1259 	    {
1260 		int	il, ir;
1261 
1262 		if (lp->ll_empty2)
1263 		    lp->ll_n2 = blob_len(lp->ll_blob) - 1;
1264 
1265 		if (lp->ll_n2 - lp->ll_n1 + 1 != blob_len(rettv->vval.v_blob))
1266 		{
1267 		    emsg(_("E972: Blob value does not have the right number of bytes"));
1268 		    return;
1269 		}
1270 		if (lp->ll_empty2)
1271 		    lp->ll_n2 = blob_len(lp->ll_blob);
1272 
1273 		ir = 0;
1274 		for (il = lp->ll_n1; il <= lp->ll_n2; il++)
1275 		    blob_set(lp->ll_blob, il,
1276 			    blob_get(rettv->vval.v_blob, ir++));
1277 	    }
1278 	    else
1279 	    {
1280 		val = (int)tv_get_number_chk(rettv, &error);
1281 		if (!error)
1282 		{
1283 		    garray_T *gap = &lp->ll_blob->bv_ga;
1284 
1285 		    // Allow for appending a byte.  Setting a byte beyond
1286 		    // the end is an error otherwise.
1287 		    if (lp->ll_n1 < gap->ga_len
1288 			    || (lp->ll_n1 == gap->ga_len
1289 				&& ga_grow(&lp->ll_blob->bv_ga, 1) == OK))
1290 		    {
1291 			blob_set(lp->ll_blob, lp->ll_n1, val);
1292 			if (lp->ll_n1 == gap->ga_len)
1293 			    ++gap->ga_len;
1294 		    }
1295 		    // error for invalid range was already given in get_lval()
1296 		}
1297 	    }
1298 	}
1299 	else if (op != NULL && *op != '=')
1300 	{
1301 	    typval_T tv;
1302 
1303 	    if (flags & ASSIGN_CONST)
1304 	    {
1305 		emsg(_(e_cannot_mod));
1306 		*endp = cc;
1307 		return;
1308 	    }
1309 
1310 	    // handle +=, -=, *=, /=, %= and .=
1311 	    di = NULL;
1312 	    if (eval_variable(lp->ll_name, (int)STRLEN(lp->ll_name),
1313 					     &tv, &di, TRUE, FALSE) == OK)
1314 	    {
1315 		if ((di == NULL
1316 			 || (!var_check_ro(di->di_flags, lp->ll_name, FALSE)
1317 			   && !tv_check_lock(&di->di_tv, lp->ll_name, FALSE)))
1318 			&& tv_op(&tv, rettv, op) == OK)
1319 		    set_var(lp->ll_name, &tv, FALSE);
1320 		clear_tv(&tv);
1321 	    }
1322 	}
1323 	else
1324 	{
1325 	    if (lp->ll_type != NULL
1326 			   && check_typval_type(lp->ll_type, rettv, 0) == FAIL)
1327 		return;
1328 	    set_var_const(lp->ll_name, lp->ll_type, rettv, copy, flags);
1329 	}
1330 	*endp = cc;
1331     }
1332     else if (value_check_lock(lp->ll_newkey == NULL
1333 		? lp->ll_tv->v_lock
1334 		: lp->ll_tv->vval.v_dict->dv_lock, lp->ll_name, FALSE))
1335 	;
1336     else if (lp->ll_range)
1337     {
1338 	listitem_T *ll_li = lp->ll_li;
1339 	int	    ll_n1 = lp->ll_n1;
1340 
1341 	if (flags & ASSIGN_CONST)
1342 	{
1343 	    emsg(_("E996: Cannot lock a range"));
1344 	    return;
1345 	}
1346 
1347 	/*
1348 	 * Check whether any of the list items is locked
1349 	 */
1350 	for (ri = rettv->vval.v_list->lv_first; ri != NULL && ll_li != NULL; )
1351 	{
1352 	    if (value_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
1353 		return;
1354 	    ri = ri->li_next;
1355 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == ll_n1))
1356 		break;
1357 	    ll_li = ll_li->li_next;
1358 	    ++ll_n1;
1359 	}
1360 
1361 	/*
1362 	 * Assign the List values to the list items.
1363 	 */
1364 	for (ri = rettv->vval.v_list->lv_first; ri != NULL; )
1365 	{
1366 	    if (op != NULL && *op != '=')
1367 		tv_op(&lp->ll_li->li_tv, &ri->li_tv, op);
1368 	    else
1369 	    {
1370 		clear_tv(&lp->ll_li->li_tv);
1371 		copy_tv(&ri->li_tv, &lp->ll_li->li_tv);
1372 	    }
1373 	    ri = ri->li_next;
1374 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == lp->ll_n1))
1375 		break;
1376 	    if (lp->ll_li->li_next == NULL)
1377 	    {
1378 		// Need to add an empty item.
1379 		if (list_append_number(lp->ll_list, 0) == FAIL)
1380 		{
1381 		    ri = NULL;
1382 		    break;
1383 		}
1384 	    }
1385 	    lp->ll_li = lp->ll_li->li_next;
1386 	    ++lp->ll_n1;
1387 	}
1388 	if (ri != NULL)
1389 	    emsg(_("E710: List value has more items than target"));
1390 	else if (lp->ll_empty2
1391 		? (lp->ll_li != NULL && lp->ll_li->li_next != NULL)
1392 		: lp->ll_n1 != lp->ll_n2)
1393 	    emsg(_("E711: List value has not enough items"));
1394     }
1395     else
1396     {
1397 	/*
1398 	 * Assign to a List or Dictionary item.
1399 	 */
1400 	if (flags & ASSIGN_CONST)
1401 	{
1402 	    emsg(_("E996: Cannot lock a list or dict"));
1403 	    return;
1404 	}
1405 
1406 	if (lp->ll_valtype != NULL
1407 			&& check_typval_type(lp->ll_valtype, rettv, 0) == FAIL)
1408 	    return;
1409 
1410 	if (lp->ll_newkey != NULL)
1411 	{
1412 	    if (op != NULL && *op != '=')
1413 	    {
1414 		semsg(_(e_letwrong), op);
1415 		return;
1416 	    }
1417 
1418 	    // Need to add an item to the Dictionary.
1419 	    di = dictitem_alloc(lp->ll_newkey);
1420 	    if (di == NULL)
1421 		return;
1422 	    if (dict_add(lp->ll_tv->vval.v_dict, di) == FAIL)
1423 	    {
1424 		vim_free(di);
1425 		return;
1426 	    }
1427 	    lp->ll_tv = &di->di_tv;
1428 	}
1429 	else if (op != NULL && *op != '=')
1430 	{
1431 	    tv_op(lp->ll_tv, rettv, op);
1432 	    return;
1433 	}
1434 	else
1435 	    clear_tv(lp->ll_tv);
1436 
1437 	/*
1438 	 * Assign the value to the variable or list item.
1439 	 */
1440 	if (copy)
1441 	    copy_tv(rettv, lp->ll_tv);
1442 	else
1443 	{
1444 	    *lp->ll_tv = *rettv;
1445 	    lp->ll_tv->v_lock = 0;
1446 	    init_tv(rettv);
1447 	}
1448     }
1449 }
1450 
1451 /*
1452  * Handle "tv1 += tv2", "tv1 -= tv2", "tv1 *= tv2", "tv1 /= tv2", "tv1 %= tv2"
1453  * and "tv1 .= tv2"
1454  * Returns OK or FAIL.
1455  */
1456     static int
1457 tv_op(typval_T *tv1, typval_T *tv2, char_u *op)
1458 {
1459     varnumber_T	n;
1460     char_u	numbuf[NUMBUFLEN];
1461     char_u	*s;
1462 
1463     // Can't do anything with a Funcref, Dict, v:true on the right.
1464     if (tv2->v_type != VAR_FUNC && tv2->v_type != VAR_DICT
1465 		      && tv2->v_type != VAR_BOOL && tv2->v_type != VAR_SPECIAL)
1466     {
1467 	switch (tv1->v_type)
1468 	{
1469 	    case VAR_UNKNOWN:
1470 	    case VAR_ANY:
1471 	    case VAR_VOID:
1472 	    case VAR_DICT:
1473 	    case VAR_FUNC:
1474 	    case VAR_PARTIAL:
1475 	    case VAR_BOOL:
1476 	    case VAR_SPECIAL:
1477 	    case VAR_JOB:
1478 	    case VAR_CHANNEL:
1479 		break;
1480 
1481 	    case VAR_BLOB:
1482 		if (*op != '+' || tv2->v_type != VAR_BLOB)
1483 		    break;
1484 		// BLOB += BLOB
1485 		if (tv1->vval.v_blob != NULL && tv2->vval.v_blob != NULL)
1486 		{
1487 		    blob_T  *b1 = tv1->vval.v_blob;
1488 		    blob_T  *b2 = tv2->vval.v_blob;
1489 		    int	i, len = blob_len(b2);
1490 		    for (i = 0; i < len; i++)
1491 			ga_append(&b1->bv_ga, blob_get(b2, i));
1492 		}
1493 		return OK;
1494 
1495 	    case VAR_LIST:
1496 		if (*op != '+' || tv2->v_type != VAR_LIST)
1497 		    break;
1498 		// List += List
1499 		if (tv2->vval.v_list != NULL)
1500 		{
1501 		    if (tv1->vval.v_list == NULL)
1502 		    {
1503 			tv1->vval.v_list = tv2->vval.v_list;
1504 			++tv1->vval.v_list->lv_refcount;
1505 		    }
1506 		    else
1507 			list_extend(tv1->vval.v_list, tv2->vval.v_list, NULL);
1508 		}
1509 		return OK;
1510 
1511 	    case VAR_NUMBER:
1512 	    case VAR_STRING:
1513 		if (tv2->v_type == VAR_LIST)
1514 		    break;
1515 		if (vim_strchr((char_u *)"+-*/%", *op) != NULL)
1516 		{
1517 		    // nr += nr , nr -= nr , nr *=nr , nr /= nr , nr %= nr
1518 		    n = tv_get_number(tv1);
1519 #ifdef FEAT_FLOAT
1520 		    if (tv2->v_type == VAR_FLOAT)
1521 		    {
1522 			float_T f = n;
1523 
1524 			if (*op == '%')
1525 			    break;
1526 			switch (*op)
1527 			{
1528 			    case '+': f += tv2->vval.v_float; break;
1529 			    case '-': f -= tv2->vval.v_float; break;
1530 			    case '*': f *= tv2->vval.v_float; break;
1531 			    case '/': f /= tv2->vval.v_float; break;
1532 			}
1533 			clear_tv(tv1);
1534 			tv1->v_type = VAR_FLOAT;
1535 			tv1->vval.v_float = f;
1536 		    }
1537 		    else
1538 #endif
1539 		    {
1540 			switch (*op)
1541 			{
1542 			    case '+': n += tv_get_number(tv2); break;
1543 			    case '-': n -= tv_get_number(tv2); break;
1544 			    case '*': n *= tv_get_number(tv2); break;
1545 			    case '/': n = num_divide(n, tv_get_number(tv2)); break;
1546 			    case '%': n = num_modulus(n, tv_get_number(tv2)); break;
1547 			}
1548 			clear_tv(tv1);
1549 			tv1->v_type = VAR_NUMBER;
1550 			tv1->vval.v_number = n;
1551 		    }
1552 		}
1553 		else
1554 		{
1555 		    if (tv2->v_type == VAR_FLOAT)
1556 			break;
1557 
1558 		    // str .= str
1559 		    s = tv_get_string(tv1);
1560 		    s = concat_str(s, tv_get_string_buf(tv2, numbuf));
1561 		    clear_tv(tv1);
1562 		    tv1->v_type = VAR_STRING;
1563 		    tv1->vval.v_string = s;
1564 		}
1565 		return OK;
1566 
1567 	    case VAR_FLOAT:
1568 #ifdef FEAT_FLOAT
1569 		{
1570 		    float_T f;
1571 
1572 		    if (*op == '%' || *op == '.'
1573 				   || (tv2->v_type != VAR_FLOAT
1574 				    && tv2->v_type != VAR_NUMBER
1575 				    && tv2->v_type != VAR_STRING))
1576 			break;
1577 		    if (tv2->v_type == VAR_FLOAT)
1578 			f = tv2->vval.v_float;
1579 		    else
1580 			f = tv_get_number(tv2);
1581 		    switch (*op)
1582 		    {
1583 			case '+': tv1->vval.v_float += f; break;
1584 			case '-': tv1->vval.v_float -= f; break;
1585 			case '*': tv1->vval.v_float *= f; break;
1586 			case '/': tv1->vval.v_float /= f; break;
1587 		    }
1588 		}
1589 #endif
1590 		return OK;
1591 	}
1592     }
1593 
1594     semsg(_(e_letwrong), op);
1595     return FAIL;
1596 }
1597 
1598 /*
1599  * Evaluate the expression used in a ":for var in expr" command.
1600  * "arg" points to "var".
1601  * Set "*errp" to TRUE for an error, FALSE otherwise;
1602  * Return a pointer that holds the info.  Null when there is an error.
1603  */
1604     void *
1605 eval_for_line(
1606     char_u	*arg,
1607     int		*errp,
1608     exarg_T	*eap,
1609     evalarg_T	*evalarg)
1610 {
1611     forinfo_T	*fi;
1612     char_u	*expr;
1613     typval_T	tv;
1614     list_T	*l;
1615     int		skip = !(evalarg->eval_flags & EVAL_EVALUATE);
1616 
1617     *errp = TRUE;	// default: there is an error
1618 
1619     fi = ALLOC_CLEAR_ONE(forinfo_T);
1620     if (fi == NULL)
1621 	return NULL;
1622 
1623     expr = skip_var_list(arg, TRUE, &fi->fi_varcount, &fi->fi_semicolon, FALSE);
1624     if (expr == NULL)
1625 	return fi;
1626 
1627     expr = skipwhite_and_linebreak(expr, evalarg);
1628     if (expr[0] != 'i' || expr[1] != 'n'
1629 				  || !(expr[2] == NUL || VIM_ISWHITE(expr[2])))
1630     {
1631 	emsg(_(e_missing_in));
1632 	return fi;
1633     }
1634 
1635     if (skip)
1636 	++emsg_skip;
1637     expr = skipwhite_and_linebreak(expr + 2, evalarg);
1638     if (eval0(expr, &tv, eap, evalarg) == OK)
1639     {
1640 	*errp = FALSE;
1641 	if (!skip)
1642 	{
1643 	    if (tv.v_type == VAR_LIST)
1644 	    {
1645 		l = tv.vval.v_list;
1646 		if (l == NULL)
1647 		{
1648 		    // a null list is like an empty list: do nothing
1649 		    clear_tv(&tv);
1650 		}
1651 		else
1652 		{
1653 		    // Need a real list here.
1654 		    CHECK_LIST_MATERIALIZE(l);
1655 
1656 		    // No need to increment the refcount, it's already set for
1657 		    // the list being used in "tv".
1658 		    fi->fi_list = l;
1659 		    list_add_watch(l, &fi->fi_lw);
1660 		    fi->fi_lw.lw_item = l->lv_first;
1661 		}
1662 	    }
1663 	    else if (tv.v_type == VAR_BLOB)
1664 	    {
1665 		fi->fi_bi = 0;
1666 		if (tv.vval.v_blob != NULL)
1667 		{
1668 		    typval_T btv;
1669 
1670 		    // Make a copy, so that the iteration still works when the
1671 		    // blob is changed.
1672 		    blob_copy(tv.vval.v_blob, &btv);
1673 		    fi->fi_blob = btv.vval.v_blob;
1674 		}
1675 		clear_tv(&tv);
1676 	    }
1677 	    else
1678 	    {
1679 		emsg(_(e_listreq));
1680 		clear_tv(&tv);
1681 	    }
1682 	}
1683     }
1684     if (skip)
1685 	--emsg_skip;
1686     fi->fi_break_count = evalarg->eval_break_count;
1687 
1688     return fi;
1689 }
1690 
1691 /*
1692  * Used when looping over a :for line, skip the "in expr" part.
1693  */
1694     void
1695 skip_for_lines(void *fi_void, evalarg_T *evalarg)
1696 {
1697     forinfo_T	*fi = (forinfo_T *)fi_void;
1698     int		i;
1699 
1700     for (i = 0; i < fi->fi_break_count; ++i)
1701 	eval_next_line(evalarg);
1702 }
1703 
1704 /*
1705  * Use the first item in a ":for" list.  Advance to the next.
1706  * Assign the values to the variable (list).  "arg" points to the first one.
1707  * Return TRUE when a valid item was found, FALSE when at end of list or
1708  * something wrong.
1709  */
1710     int
1711 next_for_item(void *fi_void, char_u *arg)
1712 {
1713     forinfo_T	*fi = (forinfo_T *)fi_void;
1714     int		result;
1715     int		flag = in_vim9script() ?  ASSIGN_NO_DECL : 0;
1716     listitem_T	*item;
1717 
1718     if (fi->fi_blob != NULL)
1719     {
1720 	typval_T	tv;
1721 
1722 	if (fi->fi_bi >= blob_len(fi->fi_blob))
1723 	    return FALSE;
1724 	tv.v_type = VAR_NUMBER;
1725 	tv.v_lock = VAR_FIXED;
1726 	tv.vval.v_number = blob_get(fi->fi_blob, fi->fi_bi);
1727 	++fi->fi_bi;
1728 	return ex_let_vars(arg, &tv, TRUE, fi->fi_semicolon,
1729 				       fi->fi_varcount, flag, NULL) == OK;
1730     }
1731 
1732     item = fi->fi_lw.lw_item;
1733     if (item == NULL)
1734 	result = FALSE;
1735     else
1736     {
1737 	fi->fi_lw.lw_item = item->li_next;
1738 	result = (ex_let_vars(arg, &item->li_tv, TRUE, fi->fi_semicolon,
1739 				      fi->fi_varcount, flag, NULL) == OK);
1740     }
1741     return result;
1742 }
1743 
1744 /*
1745  * Free the structure used to store info used by ":for".
1746  */
1747     void
1748 free_for_info(void *fi_void)
1749 {
1750     forinfo_T    *fi = (forinfo_T *)fi_void;
1751 
1752     if (fi != NULL && fi->fi_list != NULL)
1753     {
1754 	list_rem_watch(fi->fi_list, &fi->fi_lw);
1755 	list_unref(fi->fi_list);
1756     }
1757     if (fi != NULL && fi->fi_blob != NULL)
1758 	blob_unref(fi->fi_blob);
1759     vim_free(fi);
1760 }
1761 
1762     void
1763 set_context_for_expression(
1764     expand_T	*xp,
1765     char_u	*arg,
1766     cmdidx_T	cmdidx)
1767 {
1768     int		has_expr = cmdidx != CMD_let && cmdidx != CMD_var;
1769     int		c;
1770     char_u	*p;
1771 
1772     if (cmdidx == CMD_let || cmdidx == CMD_var
1773 				 || cmdidx == CMD_const || cmdidx == CMD_final)
1774     {
1775 	xp->xp_context = EXPAND_USER_VARS;
1776 	if (vim_strpbrk(arg, (char_u *)"\"'+-*/%.=!?~|&$([<>,#") == NULL)
1777 	{
1778 	    // ":let var1 var2 ...": find last space.
1779 	    for (p = arg + STRLEN(arg); p >= arg; )
1780 	    {
1781 		xp->xp_pattern = p;
1782 		MB_PTR_BACK(arg, p);
1783 		if (VIM_ISWHITE(*p))
1784 		    break;
1785 	    }
1786 	    return;
1787 	}
1788     }
1789     else
1790 	xp->xp_context = cmdidx == CMD_call ? EXPAND_FUNCTIONS
1791 							  : EXPAND_EXPRESSION;
1792     while ((xp->xp_pattern = vim_strpbrk(arg,
1793 				  (char_u *)"\"'+-*/%.=!?~|&$([<>,#")) != NULL)
1794     {
1795 	c = *xp->xp_pattern;
1796 	if (c == '&')
1797 	{
1798 	    c = xp->xp_pattern[1];
1799 	    if (c == '&')
1800 	    {
1801 		++xp->xp_pattern;
1802 		xp->xp_context = has_expr ? EXPAND_EXPRESSION : EXPAND_NOTHING;
1803 	    }
1804 	    else if (c != ' ')
1805 	    {
1806 		xp->xp_context = EXPAND_SETTINGS;
1807 		if ((c == 'l' || c == 'g') && xp->xp_pattern[2] == ':')
1808 		    xp->xp_pattern += 2;
1809 
1810 	    }
1811 	}
1812 	else if (c == '$')
1813 	{
1814 	    // environment variable
1815 	    xp->xp_context = EXPAND_ENV_VARS;
1816 	}
1817 	else if (c == '=')
1818 	{
1819 	    has_expr = TRUE;
1820 	    xp->xp_context = EXPAND_EXPRESSION;
1821 	}
1822 	else if (c == '#'
1823 		&& xp->xp_context == EXPAND_EXPRESSION)
1824 	{
1825 	    // Autoload function/variable contains '#'.
1826 	    break;
1827 	}
1828 	else if ((c == '<' || c == '#')
1829 		&& xp->xp_context == EXPAND_FUNCTIONS
1830 		&& vim_strchr(xp->xp_pattern, '(') == NULL)
1831 	{
1832 	    // Function name can start with "<SNR>" and contain '#'.
1833 	    break;
1834 	}
1835 	else if (has_expr)
1836 	{
1837 	    if (c == '"')	    // string
1838 	    {
1839 		while ((c = *++xp->xp_pattern) != NUL && c != '"')
1840 		    if (c == '\\' && xp->xp_pattern[1] != NUL)
1841 			++xp->xp_pattern;
1842 		xp->xp_context = EXPAND_NOTHING;
1843 	    }
1844 	    else if (c == '\'')	    // literal string
1845 	    {
1846 		// Trick: '' is like stopping and starting a literal string.
1847 		while ((c = *++xp->xp_pattern) != NUL && c != '\'')
1848 		    /* skip */ ;
1849 		xp->xp_context = EXPAND_NOTHING;
1850 	    }
1851 	    else if (c == '|')
1852 	    {
1853 		if (xp->xp_pattern[1] == '|')
1854 		{
1855 		    ++xp->xp_pattern;
1856 		    xp->xp_context = EXPAND_EXPRESSION;
1857 		}
1858 		else
1859 		    xp->xp_context = EXPAND_COMMANDS;
1860 	    }
1861 	    else
1862 		xp->xp_context = EXPAND_EXPRESSION;
1863 	}
1864 	else
1865 	    // Doesn't look like something valid, expand as an expression
1866 	    // anyway.
1867 	    xp->xp_context = EXPAND_EXPRESSION;
1868 	arg = xp->xp_pattern;
1869 	if (*arg != NUL)
1870 	    while ((c = *++arg) != NUL && (c == ' ' || c == '\t'))
1871 		/* skip */ ;
1872     }
1873     xp->xp_pattern = arg;
1874 }
1875 
1876 /*
1877  * Return TRUE if "pat" matches "text".
1878  * Does not use 'cpo' and always uses 'magic'.
1879  */
1880     int
1881 pattern_match(char_u *pat, char_u *text, int ic)
1882 {
1883     int		matches = FALSE;
1884     char_u	*save_cpo;
1885     regmatch_T	regmatch;
1886 
1887     // avoid 'l' flag in 'cpoptions'
1888     save_cpo = p_cpo;
1889     p_cpo = (char_u *)"";
1890     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
1891     if (regmatch.regprog != NULL)
1892     {
1893 	regmatch.rm_ic = ic;
1894 	matches = vim_regexec_nl(&regmatch, text, (colnr_T)0);
1895 	vim_regfree(regmatch.regprog);
1896     }
1897     p_cpo = save_cpo;
1898     return matches;
1899 }
1900 
1901 /*
1902  * Handle a name followed by "(".  Both for just "name(arg)" and for
1903  * "expr->name(arg)".
1904  * Returns OK or FAIL.
1905  */
1906     static int
1907 eval_func(
1908 	char_u	    **arg,	// points to "(", will be advanced
1909 	evalarg_T   *evalarg,
1910 	char_u	    *name,
1911 	int	    name_len,
1912 	typval_T    *rettv,
1913 	int	    flags,
1914 	typval_T    *basetv)	// "expr" for "expr->name(arg)"
1915 {
1916     int		evaluate = flags & EVAL_EVALUATE;
1917     char_u	*s = name;
1918     int		len = name_len;
1919     partial_T	*partial;
1920     int		ret = OK;
1921 
1922     if (!evaluate)
1923 	check_vars(s, len);
1924 
1925     // If "s" is the name of a variable of type VAR_FUNC
1926     // use its contents.
1927     s = deref_func_name(s, &len, &partial, !evaluate);
1928 
1929     // Need to make a copy, in case evaluating the arguments makes
1930     // the name invalid.
1931     s = vim_strsave(s);
1932     if (s == NULL || (flags & EVAL_CONSTANT))
1933 	ret = FAIL;
1934     else
1935     {
1936 	funcexe_T funcexe;
1937 
1938 	// Invoke the function.
1939 	CLEAR_FIELD(funcexe);
1940 	funcexe.firstline = curwin->w_cursor.lnum;
1941 	funcexe.lastline = curwin->w_cursor.lnum;
1942 	funcexe.evaluate = evaluate;
1943 	funcexe.partial = partial;
1944 	funcexe.basetv = basetv;
1945 	ret = get_func_tv(s, len, rettv, arg, evalarg, &funcexe);
1946     }
1947     vim_free(s);
1948 
1949     // If evaluate is FALSE rettv->v_type was not set in
1950     // get_func_tv, but it's needed in handle_subscript() to parse
1951     // what follows. So set it here.
1952     if (rettv->v_type == VAR_UNKNOWN && !evaluate && **arg == '(')
1953     {
1954 	rettv->vval.v_string = NULL;
1955 	rettv->v_type = VAR_FUNC;
1956     }
1957 
1958     // Stop the expression evaluation when immediately
1959     // aborting on error, or when an interrupt occurred or
1960     // an exception was thrown but not caught.
1961     if (evaluate && aborting())
1962     {
1963 	if (ret == OK)
1964 	    clear_tv(rettv);
1965 	ret = FAIL;
1966     }
1967     return ret;
1968 }
1969 
1970 /*
1971  * Get the next line source line without advancing.  But do skip over comment
1972  * lines.
1973  */
1974     static char_u *
1975 getline_peek_skip_comments(evalarg_T *evalarg)
1976 {
1977     for (;;)
1978     {
1979 	char_u *next = getline_peek(evalarg->eval_getline,
1980 							 evalarg->eval_cookie);
1981 	char_u *p;
1982 
1983 	if (next == NULL)
1984 	    break;
1985 	p = skipwhite(next);
1986 	if (*p != NUL && !vim9_comment_start(p))
1987 	    return next;
1988 	(void)eval_next_line(evalarg);
1989     }
1990     return NULL;
1991 }
1992 
1993 /*
1994  * If inside Vim9 script, "arg" points to the end of a line (ignoring a #
1995  * comment) and there is a next line, return the next line (skipping blanks)
1996  * and set "getnext".
1997  * Otherwise just return "arg" unmodified and set "getnext" to FALSE.
1998  * "arg" must point somewhere inside a line, not at the start.
1999  */
2000     char_u *
2001 eval_next_non_blank(char_u *arg, evalarg_T *evalarg, int *getnext)
2002 {
2003     char_u *p = skipwhite(arg);
2004 
2005     *getnext = FALSE;
2006     if (in_vim9script()
2007 	    && evalarg != NULL
2008 	    && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL)
2009 	    && (*p == NUL || (VIM_ISWHITE(p[-1]) && vim9_comment_start(p))))
2010     {
2011 	char_u *next;
2012 
2013 	if (evalarg->eval_cookie != NULL)
2014 	    next = getline_peek_skip_comments(evalarg);
2015 	else
2016 	    next = peek_next_line_from_context(evalarg->eval_cctx);
2017 
2018 	if (next != NULL)
2019 	{
2020 	    *getnext = TRUE;
2021 	    return skipwhite(next);
2022 	}
2023     }
2024     return p;
2025 }
2026 
2027 /*
2028  * To be called after eval_next_non_blank() sets "getnext" to TRUE.
2029  */
2030     char_u *
2031 eval_next_line(evalarg_T *evalarg)
2032 {
2033     garray_T	*gap = &evalarg->eval_ga;
2034     char_u	*line;
2035 
2036     if (evalarg->eval_cookie != NULL)
2037 	line = evalarg->eval_getline(0, evalarg->eval_cookie, 0,
2038 							   GETLINE_CONCAT_ALL);
2039     else
2040 	line = next_line_from_context(evalarg->eval_cctx, TRUE);
2041     ++evalarg->eval_break_count;
2042     if (gap->ga_itemsize > 0 && ga_grow(gap, 1) == OK)
2043     {
2044 	// Going to concatenate the lines after parsing.
2045 	((char_u **)gap->ga_data)[gap->ga_len] = line;
2046 	++gap->ga_len;
2047     }
2048     else if (evalarg->eval_cookie != NULL)
2049     {
2050 	vim_free(evalarg->eval_tofree);
2051 	evalarg->eval_tofree = line;
2052     }
2053     return skipwhite(line);
2054 }
2055 
2056 /*
2057  * Call eval_next_non_blank() and get the next line if needed.
2058  */
2059     char_u *
2060 skipwhite_and_linebreak(char_u *arg, evalarg_T *evalarg)
2061 {
2062     int	    getnext;
2063     char_u  *p = skipwhite(arg);
2064 
2065     if (evalarg == NULL)
2066 	return skipwhite(arg);
2067     eval_next_non_blank(p, evalarg, &getnext);
2068     if (getnext)
2069 	return eval_next_line(evalarg);
2070     return p;
2071 }
2072 
2073 /*
2074  * After using "evalarg" filled from "eap": free the memory.
2075  */
2076     void
2077 clear_evalarg(evalarg_T *evalarg, exarg_T *eap)
2078 {
2079     if (evalarg != NULL)
2080     {
2081 	if (evalarg->eval_tofree != NULL)
2082 	{
2083 	    if (eap != NULL)
2084 	    {
2085 		// We may need to keep the original command line, e.g. for
2086 		// ":let" it has the variable names.  But we may also need the
2087 		// new one, "nextcmd" points into it.  Keep both.
2088 		vim_free(eap->cmdline_tofree);
2089 		eap->cmdline_tofree = *eap->cmdlinep;
2090 		*eap->cmdlinep = evalarg->eval_tofree;
2091 	    }
2092 	    else
2093 		vim_free(evalarg->eval_tofree);
2094 	    evalarg->eval_tofree = NULL;
2095 	}
2096 
2097 	vim_free(evalarg->eval_tofree_lambda);
2098 	evalarg->eval_tofree_lambda = NULL;
2099     }
2100 }
2101 
2102 /*
2103  * The "evaluate" argument: When FALSE, the argument is only parsed but not
2104  * executed.  The function may return OK, but the rettv will be of type
2105  * VAR_UNKNOWN.  The function still returns FAIL for a syntax error.
2106  */
2107 
2108 /*
2109  * Handle zero level expression.
2110  * This calls eval1() and handles error message and nextcmd.
2111  * Put the result in "rettv" when returning OK and "evaluate" is TRUE.
2112  * Note: "rettv.v_lock" is not set.
2113  * "evalarg" can be NULL, EVALARG_EVALUATE or a pointer.
2114  * Return OK or FAIL.
2115  */
2116     int
2117 eval0(
2118     char_u	*arg,
2119     typval_T	*rettv,
2120     exarg_T	*eap,
2121     evalarg_T	*evalarg)
2122 {
2123     int		ret;
2124     char_u	*p;
2125     int		did_emsg_before = did_emsg;
2126     int		called_emsg_before = called_emsg;
2127     int		flags = evalarg == NULL ? 0 : evalarg->eval_flags;
2128 
2129     p = skipwhite(arg);
2130     ret = eval1(&p, rettv, evalarg);
2131     p = skipwhite(p);
2132 
2133     if (ret == FAIL || !ends_excmd2(arg, p))
2134     {
2135 	if (ret != FAIL)
2136 	    clear_tv(rettv);
2137 	/*
2138 	 * Report the invalid expression unless the expression evaluation has
2139 	 * been cancelled due to an aborting error, an interrupt, or an
2140 	 * exception, or we already gave a more specific error.
2141 	 * Also check called_emsg for when using assert_fails().
2142 	 */
2143 	if (!aborting()
2144 		&& did_emsg == did_emsg_before
2145 		&& called_emsg == called_emsg_before
2146 		&& (flags & EVAL_CONSTANT) == 0)
2147 	    semsg(_(e_invexpr2), arg);
2148 	ret = FAIL;
2149     }
2150 
2151     if (eap != NULL)
2152 	eap->nextcmd = check_nextcmd(p);
2153 
2154     return ret;
2155 }
2156 
2157 /*
2158  * Handle top level expression:
2159  *	expr2 ? expr1 : expr1
2160  *	expr2 ?? expr1
2161  *
2162  * "arg" must point to the first non-white of the expression.
2163  * "arg" is advanced to just after the recognized expression.
2164  *
2165  * Note: "rettv.v_lock" is not set.
2166  *
2167  * Return OK or FAIL.
2168  */
2169     int
2170 eval1(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2171 {
2172     char_u  *p;
2173     int	    getnext;
2174 
2175     CLEAR_POINTER(rettv);
2176 
2177     /*
2178      * Get the first variable.
2179      */
2180     if (eval2(arg, rettv, evalarg) == FAIL)
2181 	return FAIL;
2182 
2183     p = eval_next_non_blank(*arg, evalarg, &getnext);
2184     if (*p == '?')
2185     {
2186 	int		op_falsy = p[1] == '?';
2187 	int		result;
2188 	typval_T	var2;
2189 	evalarg_T	*evalarg_used = evalarg;
2190 	evalarg_T	local_evalarg;
2191 	int		orig_flags;
2192 	int		evaluate;
2193 	int		vim9script = in_vim9script();
2194 
2195 	if (evalarg == NULL)
2196 	{
2197 	    CLEAR_FIELD(local_evalarg);
2198 	    evalarg_used = &local_evalarg;
2199 	}
2200 	orig_flags = evalarg_used->eval_flags;
2201 	evaluate = evalarg_used->eval_flags & EVAL_EVALUATE;
2202 
2203 	if (getnext)
2204 	    *arg = eval_next_line(evalarg_used);
2205 	else
2206 	{
2207 	    if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
2208 	    {
2209 		error_white_both(p, 1);
2210 		clear_tv(rettv);
2211 		return FAIL;
2212 	    }
2213 	    *arg = p;
2214 	}
2215 
2216 	result = FALSE;
2217 	if (evaluate)
2218 	{
2219 	    int		error = FALSE;
2220 
2221 	    if (op_falsy)
2222 		result = tv2bool(rettv);
2223 	    else if (vim9script)
2224 		result = tv_get_bool_chk(rettv, &error);
2225 	    else if (tv_get_number_chk(rettv, &error) != 0)
2226 		result = TRUE;
2227 	    if (error || !op_falsy || !result)
2228 		clear_tv(rettv);
2229 	    if (error)
2230 		return FAIL;
2231 	}
2232 
2233 	/*
2234 	 * Get the second variable.  Recursive!
2235 	 */
2236 	if (op_falsy)
2237 	    ++*arg;
2238 	if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[1]))
2239 	{
2240 	    error_white_both(p, 1);
2241 	    clear_tv(rettv);
2242 	    return FAIL;
2243 	}
2244 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg_used);
2245 	evalarg_used->eval_flags = (op_falsy ? !result : result)
2246 				    ? orig_flags : orig_flags & ~EVAL_EVALUATE;
2247 	if (eval1(arg, &var2, evalarg_used) == FAIL)
2248 	{
2249 	    evalarg_used->eval_flags = orig_flags;
2250 	    return FAIL;
2251 	}
2252 	if (!op_falsy || !result)
2253 	    *rettv = var2;
2254 
2255 	if (!op_falsy)
2256 	{
2257 	    /*
2258 	     * Check for the ":".
2259 	     */
2260 	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
2261 	    if (*p != ':')
2262 	    {
2263 		emsg(_(e_missing_colon));
2264 		if (evaluate && result)
2265 		    clear_tv(rettv);
2266 		evalarg_used->eval_flags = orig_flags;
2267 		return FAIL;
2268 	    }
2269 	    if (getnext)
2270 		*arg = eval_next_line(evalarg_used);
2271 	    else
2272 	    {
2273 		if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
2274 		{
2275 		    error_white_both(p, 1);
2276 		    clear_tv(rettv);
2277 		    evalarg_used->eval_flags = orig_flags;
2278 		    return FAIL;
2279 		}
2280 		*arg = p;
2281 	    }
2282 
2283 	    /*
2284 	     * Get the third variable.  Recursive!
2285 	     */
2286 	    if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[1]))
2287 	    {
2288 		error_white_both(p, 1);
2289 		clear_tv(rettv);
2290 		evalarg_used->eval_flags = orig_flags;
2291 		return FAIL;
2292 	    }
2293 	    *arg = skipwhite_and_linebreak(*arg + 1, evalarg_used);
2294 	    evalarg_used->eval_flags = !result ? orig_flags
2295 						 : orig_flags & ~EVAL_EVALUATE;
2296 	    if (eval1(arg, &var2, evalarg_used) == FAIL)
2297 	    {
2298 		if (evaluate && result)
2299 		    clear_tv(rettv);
2300 		evalarg_used->eval_flags = orig_flags;
2301 		return FAIL;
2302 	    }
2303 	    if (evaluate && !result)
2304 		*rettv = var2;
2305 	}
2306 
2307 	if (evalarg == NULL)
2308 	    clear_evalarg(&local_evalarg, NULL);
2309 	else
2310 	    evalarg->eval_flags = orig_flags;
2311     }
2312 
2313     return OK;
2314 }
2315 
2316 /*
2317  * Handle first level expression:
2318  *	expr2 || expr2 || expr2	    logical OR
2319  *
2320  * "arg" must point to the first non-white of the expression.
2321  * "arg" is advanced to just after the recognized expression.
2322  *
2323  * Return OK or FAIL.
2324  */
2325     static int
2326 eval2(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2327 {
2328     char_u	*p;
2329     int		getnext;
2330 
2331     /*
2332      * Get the first variable.
2333      */
2334     if (eval3(arg, rettv, evalarg) == FAIL)
2335 	return FAIL;
2336 
2337     /*
2338      * Handle the  "||" operator.
2339      */
2340     p = eval_next_non_blank(*arg, evalarg, &getnext);
2341     if (p[0] == '|' && p[1] == '|')
2342     {
2343 	evalarg_T   *evalarg_used = evalarg;
2344 	evalarg_T   local_evalarg;
2345 	int	    evaluate;
2346 	int	    orig_flags;
2347 	long	    result = FALSE;
2348 	typval_T    var2;
2349 	int	    error = FALSE;
2350 	int	    vim9script = in_vim9script();
2351 
2352 	if (evalarg == NULL)
2353 	{
2354 	    CLEAR_FIELD(local_evalarg);
2355 	    evalarg_used = &local_evalarg;
2356 	}
2357 	orig_flags = evalarg_used->eval_flags;
2358 	evaluate = orig_flags & EVAL_EVALUATE;
2359 	if (evaluate)
2360 	{
2361 	    if (vim9script)
2362 		result = tv_get_bool_chk(rettv, &error);
2363 	    else if (tv_get_number_chk(rettv, &error) != 0)
2364 		result = TRUE;
2365 	    clear_tv(rettv);
2366 	    if (error)
2367 		return FAIL;
2368 	}
2369 
2370 	/*
2371 	 * Repeat until there is no following "||".
2372 	 */
2373 	while (p[0] == '|' && p[1] == '|')
2374 	{
2375 	    if (getnext)
2376 		*arg = eval_next_line(evalarg_used);
2377 	    else
2378 	    {
2379 		if (evaluate && in_vim9script() && !VIM_ISWHITE(p[-1]))
2380 		{
2381 		    error_white_both(p, 2);
2382 		    clear_tv(rettv);
2383 		    return FAIL;
2384 		}
2385 		*arg = p;
2386 	    }
2387 
2388 	    /*
2389 	     * Get the second variable.
2390 	     */
2391 	    if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[2]))
2392 	    {
2393 		error_white_both(p, 2);
2394 		clear_tv(rettv);
2395 		return FAIL;
2396 	    }
2397 	    *arg = skipwhite_and_linebreak(*arg + 2, evalarg_used);
2398 	    evalarg_used->eval_flags = !result ? orig_flags
2399 						 : orig_flags & ~EVAL_EVALUATE;
2400 	    if (eval3(arg, &var2, evalarg_used) == FAIL)
2401 		return FAIL;
2402 
2403 	    /*
2404 	     * Compute the result.
2405 	     */
2406 	    if (evaluate && !result)
2407 	    {
2408 		if (vim9script)
2409 		    result = tv_get_bool_chk(&var2, &error);
2410 		else if (tv_get_number_chk(&var2, &error) != 0)
2411 		    result = TRUE;
2412 		clear_tv(&var2);
2413 		if (error)
2414 		    return FAIL;
2415 	    }
2416 	    if (evaluate)
2417 	    {
2418 		if (vim9script)
2419 		{
2420 		    rettv->v_type = VAR_BOOL;
2421 		    rettv->vval.v_number = result ? VVAL_TRUE : VVAL_FALSE;
2422 		}
2423 		else
2424 		{
2425 		    rettv->v_type = VAR_NUMBER;
2426 		    rettv->vval.v_number = result;
2427 		}
2428 	    }
2429 
2430 	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
2431 	}
2432 
2433 	if (evalarg == NULL)
2434 	    clear_evalarg(&local_evalarg, NULL);
2435 	else
2436 	    evalarg->eval_flags = orig_flags;
2437     }
2438 
2439     return OK;
2440 }
2441 
2442 /*
2443  * Handle second level expression:
2444  *	expr3 && expr3 && expr3	    logical AND
2445  *
2446  * "arg" must point to the first non-white of the expression.
2447  * "arg" is advanced to just after the recognized expression.
2448  *
2449  * Return OK or FAIL.
2450  */
2451     static int
2452 eval3(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2453 {
2454     char_u	*p;
2455     int		getnext;
2456 
2457     /*
2458      * Get the first variable.
2459      */
2460     if (eval4(arg, rettv, evalarg) == FAIL)
2461 	return FAIL;
2462 
2463     /*
2464      * Handle the "&&" operator.
2465      */
2466     p = eval_next_non_blank(*arg, evalarg, &getnext);
2467     if (p[0] == '&' && p[1] == '&')
2468     {
2469 	evalarg_T   *evalarg_used = evalarg;
2470 	evalarg_T   local_evalarg;
2471 	int	    orig_flags;
2472 	int	    evaluate;
2473 	long	    result = TRUE;
2474 	typval_T    var2;
2475 	int	    error = FALSE;
2476 	int	    vim9script = in_vim9script();
2477 
2478 	if (evalarg == NULL)
2479 	{
2480 	    CLEAR_FIELD(local_evalarg);
2481 	    evalarg_used = &local_evalarg;
2482 	}
2483 	orig_flags = evalarg_used->eval_flags;
2484 	evaluate = orig_flags & EVAL_EVALUATE;
2485 	if (evaluate)
2486 	{
2487 	    if (vim9script)
2488 		result = tv_get_bool_chk(rettv, &error);
2489 	    else if (tv_get_number_chk(rettv, &error) == 0)
2490 		result = FALSE;
2491 	    clear_tv(rettv);
2492 	    if (error)
2493 		return FAIL;
2494 	}
2495 
2496 	/*
2497 	 * Repeat until there is no following "&&".
2498 	 */
2499 	while (p[0] == '&' && p[1] == '&')
2500 	{
2501 	    if (getnext)
2502 		*arg = eval_next_line(evalarg_used);
2503 	    else
2504 	    {
2505 		if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
2506 		{
2507 		    error_white_both(p, 2);
2508 		    clear_tv(rettv);
2509 		    return FAIL;
2510 		}
2511 		*arg = p;
2512 	    }
2513 
2514 	    /*
2515 	     * Get the second variable.
2516 	     */
2517 	    if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[2]))
2518 	    {
2519 		error_white_both(p, 2);
2520 		clear_tv(rettv);
2521 		return FAIL;
2522 	    }
2523 	    *arg = skipwhite_and_linebreak(*arg + 2, evalarg_used);
2524 	    evalarg_used->eval_flags = result ? orig_flags
2525 						 : orig_flags & ~EVAL_EVALUATE;
2526 	    CLEAR_FIELD(var2);
2527 	    if (eval4(arg, &var2, evalarg_used) == FAIL)
2528 		return FAIL;
2529 
2530 	    /*
2531 	     * Compute the result.
2532 	     */
2533 	    if (evaluate && result)
2534 	    {
2535 		if (vim9script)
2536 		    result = tv_get_bool_chk(&var2, &error);
2537 		else if (tv_get_number_chk(&var2, &error) == 0)
2538 		    result = FALSE;
2539 		clear_tv(&var2);
2540 		if (error)
2541 		    return FAIL;
2542 	    }
2543 	    if (evaluate)
2544 	    {
2545 		if (vim9script)
2546 		{
2547 		    rettv->v_type = VAR_BOOL;
2548 		    rettv->vval.v_number = result ? VVAL_TRUE : VVAL_FALSE;
2549 		}
2550 		else
2551 		{
2552 		    rettv->v_type = VAR_NUMBER;
2553 		    rettv->vval.v_number = result;
2554 		}
2555 	    }
2556 
2557 	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
2558 	}
2559 
2560 	if (evalarg == NULL)
2561 	    clear_evalarg(&local_evalarg, NULL);
2562 	else
2563 	    evalarg->eval_flags = orig_flags;
2564     }
2565 
2566     return OK;
2567 }
2568 
2569 /*
2570  * Handle third level expression:
2571  *	var1 == var2
2572  *	var1 =~ var2
2573  *	var1 != var2
2574  *	var1 !~ var2
2575  *	var1 > var2
2576  *	var1 >= var2
2577  *	var1 < var2
2578  *	var1 <= var2
2579  *	var1 is var2
2580  *	var1 isnot var2
2581  *
2582  * "arg" must point to the first non-white of the expression.
2583  * "arg" is advanced to just after the recognized expression.
2584  *
2585  * Return OK or FAIL.
2586  */
2587     static int
2588 eval4(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2589 {
2590     char_u	*p;
2591     int		getnext;
2592     exptype_T	type = EXPR_UNKNOWN;
2593     int		len = 2;
2594     int		type_is = FALSE;
2595 
2596     /*
2597      * Get the first variable.
2598      */
2599     if (eval5(arg, rettv, evalarg) == FAIL)
2600 	return FAIL;
2601 
2602     p = eval_next_non_blank(*arg, evalarg, &getnext);
2603     type = get_compare_type(p, &len, &type_is);
2604 
2605     /*
2606      * If there is a comparative operator, use it.
2607      */
2608     if (type != EXPR_UNKNOWN)
2609     {
2610 	typval_T    var2;
2611 	int	    ic;
2612 	int	    vim9script = in_vim9script();
2613 	int	    evaluate = evalarg == NULL
2614 				   ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
2615 
2616 	if (getnext)
2617 	    *arg = eval_next_line(evalarg);
2618 	else if (evaluate && vim9script && !VIM_ISWHITE(**arg))
2619 	{
2620 	    error_white_both(p, len);
2621 	    clear_tv(rettv);
2622 	    return FAIL;
2623 	}
2624 
2625 	if (vim9script && type_is && (p[len] == '?' || p[len] == '#'))
2626 	{
2627 	    semsg(_(e_invexpr2), p);
2628 	    clear_tv(rettv);
2629 	    return FAIL;
2630 	}
2631 
2632 	// extra question mark appended: ignore case
2633 	if (p[len] == '?')
2634 	{
2635 	    ic = TRUE;
2636 	    ++len;
2637 	}
2638 	// extra '#' appended: match case
2639 	else if (p[len] == '#')
2640 	{
2641 	    ic = FALSE;
2642 	    ++len;
2643 	}
2644 	// nothing appended: use 'ignorecase' if not in Vim script
2645 	else
2646 	    ic = vim9script ? FALSE : p_ic;
2647 
2648 	/*
2649 	 * Get the second variable.
2650 	 */
2651 	if (evaluate && vim9script && !IS_WHITE_OR_NUL(p[len]))
2652 	{
2653 	    error_white_both(p, 1);
2654 	    clear_tv(rettv);
2655 	    return FAIL;
2656 	}
2657 	*arg = skipwhite_and_linebreak(p + len, evalarg);
2658 	if (eval5(arg, &var2, evalarg) == FAIL)
2659 	{
2660 	    clear_tv(rettv);
2661 	    return FAIL;
2662 	}
2663 	if (evaluate)
2664 	{
2665 	    int ret;
2666 
2667 	    if (vim9script && check_compare_types(type, rettv, &var2) == FAIL)
2668 	    {
2669 		ret = FAIL;
2670 		clear_tv(rettv);
2671 	    }
2672 	    else
2673 		ret = typval_compare(rettv, &var2, type, ic);
2674 	    clear_tv(&var2);
2675 	    return ret;
2676 	}
2677     }
2678 
2679     return OK;
2680 }
2681 
2682 /*
2683  * Make a copy of blob "tv1" and append blob "tv2".
2684  */
2685     void
2686 eval_addblob(typval_T *tv1, typval_T *tv2)
2687 {
2688     blob_T  *b1 = tv1->vval.v_blob;
2689     blob_T  *b2 = tv2->vval.v_blob;
2690     blob_T  *b = blob_alloc();
2691     int	    i;
2692 
2693     if (b != NULL)
2694     {
2695 	for (i = 0; i < blob_len(b1); i++)
2696 	    ga_append(&b->bv_ga, blob_get(b1, i));
2697 	for (i = 0; i < blob_len(b2); i++)
2698 	    ga_append(&b->bv_ga, blob_get(b2, i));
2699 
2700 	clear_tv(tv1);
2701 	rettv_blob_set(tv1, b);
2702     }
2703 }
2704 
2705 /*
2706  * Make a copy of list "tv1" and append list "tv2".
2707  */
2708     int
2709 eval_addlist(typval_T *tv1, typval_T *tv2)
2710 {
2711     typval_T var3;
2712 
2713     // concatenate Lists
2714     if (list_concat(tv1->vval.v_list, tv2->vval.v_list, &var3) == FAIL)
2715     {
2716 	clear_tv(tv1);
2717 	clear_tv(tv2);
2718 	return FAIL;
2719     }
2720     clear_tv(tv1);
2721     *tv1 = var3;
2722     return OK;
2723 }
2724 
2725 /*
2726  * Handle fourth level expression:
2727  *	+	number addition
2728  *	-	number subtraction
2729  *	.	string concatenation (if script version is 1)
2730  *	..	string concatenation
2731  *
2732  * "arg" must point to the first non-white of the expression.
2733  * "arg" is advanced to just after the recognized expression.
2734  *
2735  * Return OK or FAIL.
2736  */
2737     static int
2738 eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
2739 {
2740     /*
2741      * Get the first variable.
2742      */
2743     if (eval6(arg, rettv, evalarg, FALSE) == FAIL)
2744 	return FAIL;
2745 
2746     /*
2747      * Repeat computing, until no '+', '-' or '.' is following.
2748      */
2749     for (;;)
2750     {
2751 	int	    evaluate;
2752 	int	    getnext;
2753 	char_u	    *p;
2754 	int	    op;
2755 	int	    oplen;
2756 	int	    concat;
2757 	typval_T    var2;
2758 	int	    vim9script = in_vim9script();
2759 
2760 	// "." is only string concatenation when scriptversion is 1
2761 	p = eval_next_non_blank(*arg, evalarg, &getnext);
2762 	op = *p;
2763 	concat = op == '.' && (*(p + 1) == '.' || current_sctx.sc_version < 2);
2764 	if (op != '+' && op != '-' && !concat)
2765 	    break;
2766 
2767 	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
2768 	oplen = (concat && p[1] == '.') ? 2 : 1;
2769 	if (getnext)
2770 	    *arg = eval_next_line(evalarg);
2771 	else
2772 	{
2773 	    if (evaluate && vim9script && !VIM_ISWHITE(**arg))
2774 	    {
2775 		error_white_both(p, oplen);
2776 		clear_tv(rettv);
2777 		return FAIL;
2778 	    }
2779 	    *arg = p;
2780 	}
2781 	if ((op != '+' || (rettv->v_type != VAR_LIST
2782 						 && rettv->v_type != VAR_BLOB))
2783 #ifdef FEAT_FLOAT
2784 		&& (op == '.' || rettv->v_type != VAR_FLOAT)
2785 #endif
2786 		&& evaluate)
2787 	{
2788 	    int		error = FALSE;
2789 
2790 	    // For "list + ...", an illegal use of the first operand as
2791 	    // a number cannot be determined before evaluating the 2nd
2792 	    // operand: if this is also a list, all is ok.
2793 	    // For "something . ...", "something - ..." or "non-list + ...",
2794 	    // we know that the first operand needs to be a string or number
2795 	    // without evaluating the 2nd operand.  So check before to avoid
2796 	    // side effects after an error.
2797 	    if (op != '.')
2798 		tv_get_number_chk(rettv, &error);
2799 	    if ((op == '.' && tv_get_string_chk(rettv) == NULL) || error)
2800 	    {
2801 		clear_tv(rettv);
2802 		return FAIL;
2803 	    }
2804 	}
2805 
2806 	/*
2807 	 * Get the second variable.
2808 	 */
2809 	if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[oplen]))
2810 	{
2811 	    error_white_both(p, oplen);
2812 	    clear_tv(rettv);
2813 	    return FAIL;
2814 	}
2815 	*arg = skipwhite_and_linebreak(*arg + oplen, evalarg);
2816 	if (eval6(arg, &var2, evalarg, !vim9script && op == '.') == FAIL)
2817 	{
2818 	    clear_tv(rettv);
2819 	    return FAIL;
2820 	}
2821 
2822 	if (evaluate)
2823 	{
2824 	    /*
2825 	     * Compute the result.
2826 	     */
2827 	    if (op == '.')
2828 	    {
2829 		char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
2830 		char_u	*s1 = tv_get_string_buf(rettv, buf1);
2831 		char_u	*s2 = NULL;
2832 
2833 		if (vim9script && (var2.v_type == VAR_VOID
2834 			|| var2.v_type == VAR_CHANNEL
2835 			|| var2.v_type == VAR_JOB))
2836 		    emsg(_(e_inval_string));
2837 #ifdef FEAT_FLOAT
2838 		else if (vim9script && var2.v_type == VAR_FLOAT)
2839 		{
2840 		    vim_snprintf((char *)buf2, NUMBUFLEN, "%g",
2841 							    var2.vval.v_float);
2842 		    s2 = buf2;
2843 		}
2844 #endif
2845 		else
2846 		    s2 = tv_get_string_buf_chk(&var2, buf2);
2847 		if (s2 == NULL)		// type error ?
2848 		{
2849 		    clear_tv(rettv);
2850 		    clear_tv(&var2);
2851 		    return FAIL;
2852 		}
2853 		p = concat_str(s1, s2);
2854 		clear_tv(rettv);
2855 		rettv->v_type = VAR_STRING;
2856 		rettv->vval.v_string = p;
2857 	    }
2858 	    else if (op == '+' && rettv->v_type == VAR_BLOB
2859 						   && var2.v_type == VAR_BLOB)
2860 		eval_addblob(rettv, &var2);
2861 	    else if (op == '+' && rettv->v_type == VAR_LIST
2862 						   && var2.v_type == VAR_LIST)
2863 	    {
2864 		if (eval_addlist(rettv, &var2) == FAIL)
2865 		    return FAIL;
2866 	    }
2867 	    else
2868 	    {
2869 		int		error = FALSE;
2870 		varnumber_T	n1, n2;
2871 #ifdef FEAT_FLOAT
2872 		float_T	    f1 = 0, f2 = 0;
2873 
2874 		if (rettv->v_type == VAR_FLOAT)
2875 		{
2876 		    f1 = rettv->vval.v_float;
2877 		    n1 = 0;
2878 		}
2879 		else
2880 #endif
2881 		{
2882 		    n1 = tv_get_number_chk(rettv, &error);
2883 		    if (error)
2884 		    {
2885 			// This can only happen for "list + non-list".  For
2886 			// "non-list + ..." or "something - ...", we returned
2887 			// before evaluating the 2nd operand.
2888 			clear_tv(rettv);
2889 			return FAIL;
2890 		    }
2891 #ifdef FEAT_FLOAT
2892 		    if (var2.v_type == VAR_FLOAT)
2893 			f1 = n1;
2894 #endif
2895 		}
2896 #ifdef FEAT_FLOAT
2897 		if (var2.v_type == VAR_FLOAT)
2898 		{
2899 		    f2 = var2.vval.v_float;
2900 		    n2 = 0;
2901 		}
2902 		else
2903 #endif
2904 		{
2905 		    n2 = tv_get_number_chk(&var2, &error);
2906 		    if (error)
2907 		    {
2908 			clear_tv(rettv);
2909 			clear_tv(&var2);
2910 			return FAIL;
2911 		    }
2912 #ifdef FEAT_FLOAT
2913 		    if (rettv->v_type == VAR_FLOAT)
2914 			f2 = n2;
2915 #endif
2916 		}
2917 		clear_tv(rettv);
2918 
2919 #ifdef FEAT_FLOAT
2920 		// If there is a float on either side the result is a float.
2921 		if (rettv->v_type == VAR_FLOAT || var2.v_type == VAR_FLOAT)
2922 		{
2923 		    if (op == '+')
2924 			f1 = f1 + f2;
2925 		    else
2926 			f1 = f1 - f2;
2927 		    rettv->v_type = VAR_FLOAT;
2928 		    rettv->vval.v_float = f1;
2929 		}
2930 		else
2931 #endif
2932 		{
2933 		    if (op == '+')
2934 			n1 = n1 + n2;
2935 		    else
2936 			n1 = n1 - n2;
2937 		    rettv->v_type = VAR_NUMBER;
2938 		    rettv->vval.v_number = n1;
2939 		}
2940 	    }
2941 	    clear_tv(&var2);
2942 	}
2943     }
2944     return OK;
2945 }
2946 
2947 /*
2948  * Handle fifth level expression:
2949  *	*	number multiplication
2950  *	/	number division
2951  *	%	number modulo
2952  *
2953  * "arg" must point to the first non-white of the expression.
2954  * "arg" is advanced to just after the recognized expression.
2955  *
2956  * Return OK or FAIL.
2957  */
2958     static int
2959 eval6(
2960     char_u	**arg,
2961     typval_T	*rettv,
2962     evalarg_T	*evalarg,
2963     int		want_string)  // after "." operator
2964 {
2965 #ifdef FEAT_FLOAT
2966     int	    use_float = FALSE;
2967 #endif
2968 
2969     /*
2970      * Get the first variable.
2971      */
2972     if (eval7(arg, rettv, evalarg, want_string) == FAIL)
2973 	return FAIL;
2974 
2975     /*
2976      * Repeat computing, until no '*', '/' or '%' is following.
2977      */
2978     for (;;)
2979     {
2980 	int	    evaluate;
2981 	int	    getnext;
2982 	typval_T    var2;
2983 	char_u	    *p;
2984 	int	    op;
2985 	varnumber_T n1, n2;
2986 #ifdef FEAT_FLOAT
2987 	float_T	    f1, f2;
2988 #endif
2989 	int	    error;
2990 
2991 	p = eval_next_non_blank(*arg, evalarg, &getnext);
2992 	op = *p;
2993 	if (op != '*' && op != '/' && op != '%')
2994 	    break;
2995 
2996 	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
2997 	if (getnext)
2998 	    *arg = eval_next_line(evalarg);
2999 	else
3000 	{
3001 	    if (evaluate && in_vim9script() && !VIM_ISWHITE(**arg))
3002 	    {
3003 		error_white_both(p, 1);
3004 		clear_tv(rettv);
3005 		return FAIL;
3006 	    }
3007 	    *arg = p;
3008 	}
3009 
3010 #ifdef FEAT_FLOAT
3011 	f1 = 0;
3012 	f2 = 0;
3013 #endif
3014 	error = FALSE;
3015 	if (evaluate)
3016 	{
3017 #ifdef FEAT_FLOAT
3018 	    if (rettv->v_type == VAR_FLOAT)
3019 	    {
3020 		f1 = rettv->vval.v_float;
3021 		use_float = TRUE;
3022 		n1 = 0;
3023 	    }
3024 	    else
3025 #endif
3026 		n1 = tv_get_number_chk(rettv, &error);
3027 	    clear_tv(rettv);
3028 	    if (error)
3029 		return FAIL;
3030 	}
3031 	else
3032 	    n1 = 0;
3033 
3034 	/*
3035 	 * Get the second variable.
3036 	 */
3037 	if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[1]))
3038 	{
3039 	    error_white_both(p, 1);
3040 	    clear_tv(rettv);
3041 	    return FAIL;
3042 	}
3043 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3044 	if (eval7(arg, &var2, evalarg, FALSE) == FAIL)
3045 	    return FAIL;
3046 
3047 	if (evaluate)
3048 	{
3049 #ifdef FEAT_FLOAT
3050 	    if (var2.v_type == VAR_FLOAT)
3051 	    {
3052 		if (!use_float)
3053 		{
3054 		    f1 = n1;
3055 		    use_float = TRUE;
3056 		}
3057 		f2 = var2.vval.v_float;
3058 		n2 = 0;
3059 	    }
3060 	    else
3061 #endif
3062 	    {
3063 		n2 = tv_get_number_chk(&var2, &error);
3064 		clear_tv(&var2);
3065 		if (error)
3066 		    return FAIL;
3067 #ifdef FEAT_FLOAT
3068 		if (use_float)
3069 		    f2 = n2;
3070 #endif
3071 	    }
3072 
3073 	    /*
3074 	     * Compute the result.
3075 	     * When either side is a float the result is a float.
3076 	     */
3077 #ifdef FEAT_FLOAT
3078 	    if (use_float)
3079 	    {
3080 		if (op == '*')
3081 		    f1 = f1 * f2;
3082 		else if (op == '/')
3083 		{
3084 # ifdef VMS
3085 		    // VMS crashes on divide by zero, work around it
3086 		    if (f2 == 0.0)
3087 		    {
3088 			if (f1 == 0)
3089 			    f1 = -1 * __F_FLT_MAX - 1L;   // similar to NaN
3090 			else if (f1 < 0)
3091 			    f1 = -1 * __F_FLT_MAX;
3092 			else
3093 			    f1 = __F_FLT_MAX;
3094 		    }
3095 		    else
3096 			f1 = f1 / f2;
3097 # else
3098 		    // We rely on the floating point library to handle divide
3099 		    // by zero to result in "inf" and not a crash.
3100 		    f1 = f1 / f2;
3101 # endif
3102 		}
3103 		else
3104 		{
3105 		    emsg(_(e_modulus));
3106 		    return FAIL;
3107 		}
3108 		rettv->v_type = VAR_FLOAT;
3109 		rettv->vval.v_float = f1;
3110 	    }
3111 	    else
3112 #endif
3113 	    {
3114 		if (op == '*')
3115 		    n1 = n1 * n2;
3116 		else if (op == '/')
3117 		    n1 = num_divide(n1, n2);
3118 		else
3119 		    n1 = num_modulus(n1, n2);
3120 
3121 		rettv->v_type = VAR_NUMBER;
3122 		rettv->vval.v_number = n1;
3123 	    }
3124 	}
3125     }
3126 
3127     return OK;
3128 }
3129 
3130 /*
3131  * Handle sixth level expression:
3132  *  number		number constant
3133  *  0zFFFFFFFF		Blob constant
3134  *  "string"		string constant
3135  *  'string'		literal string constant
3136  *  &option-name	option value
3137  *  @r			register contents
3138  *  identifier		variable value
3139  *  function()		function call
3140  *  $VAR		environment variable
3141  *  (expression)	nested expression
3142  *  [expr, expr]	List
3143  *  {arg, arg -> expr}	Lambda
3144  *  {key: val, key: val}   Dictionary
3145  *  #{key: val, key: val}  Dictionary with literal keys
3146  *
3147  *  Also handle:
3148  *  ! in front		logical NOT
3149  *  - in front		unary minus
3150  *  + in front		unary plus (ignored)
3151  *  trailing []		subscript in String or List
3152  *  trailing .name	entry in Dictionary
3153  *  trailing ->name()	method call
3154  *
3155  * "arg" must point to the first non-white of the expression.
3156  * "arg" is advanced to just after the recognized expression.
3157  *
3158  * Return OK or FAIL.
3159  */
3160     static int
3161 eval7(
3162     char_u	**arg,
3163     typval_T	*rettv,
3164     evalarg_T	*evalarg,
3165     int		want_string)	// after "." operator
3166 {
3167     int		evaluate = evalarg != NULL
3168 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3169     int		len;
3170     char_u	*s;
3171     char_u	*start_leader, *end_leader;
3172     int		ret = OK;
3173     char_u	*alias;
3174 
3175     /*
3176      * Initialise variable so that clear_tv() can't mistake this for a
3177      * string and free a string that isn't there.
3178      */
3179     rettv->v_type = VAR_UNKNOWN;
3180 
3181     /*
3182      * Skip '!', '-' and '+' characters.  They are handled later.
3183      */
3184     start_leader = *arg;
3185     while (**arg == '!' || **arg == '-' || **arg == '+')
3186 	*arg = skipwhite(*arg + 1);
3187     end_leader = *arg;
3188 
3189     if (**arg == '.' && (!isdigit(*(*arg + 1))
3190 #ifdef FEAT_FLOAT
3191 	    || current_sctx.sc_version < 2
3192 #endif
3193 	    ))
3194     {
3195 	semsg(_(e_invexpr2), *arg);
3196 	++*arg;
3197 	return FAIL;
3198     }
3199 
3200     switch (**arg)
3201     {
3202     /*
3203      * Number constant.
3204      */
3205     case '0':
3206     case '1':
3207     case '2':
3208     case '3':
3209     case '4':
3210     case '5':
3211     case '6':
3212     case '7':
3213     case '8':
3214     case '9':
3215     case '.':	ret = eval_number(arg, rettv, evaluate, want_string);
3216 
3217 		// Apply prefixed "-" and "+" now.  Matters especially when
3218 		// "->" follows.
3219 		if (ret == OK && evaluate && end_leader > start_leader
3220 						  && rettv->v_type != VAR_BLOB)
3221 		    ret = eval7_leader(rettv, TRUE, start_leader, &end_leader);
3222 		break;
3223 
3224     /*
3225      * String constant: "string".
3226      */
3227     case '"':	ret = eval_string(arg, rettv, evaluate);
3228 		break;
3229 
3230     /*
3231      * Literal string constant: 'str''ing'.
3232      */
3233     case '\'':	ret = eval_lit_string(arg, rettv, evaluate);
3234 		break;
3235 
3236     /*
3237      * List: [expr, expr]
3238      */
3239     case '[':	ret = eval_list(arg, rettv, evalarg, TRUE);
3240 		break;
3241 
3242     /*
3243      * Dictionary: #{key: val, key: val}
3244      */
3245     case '#':	if ((*arg)[1] == '{')
3246 		{
3247 		    ++*arg;
3248 		    ret = eval_dict(arg, rettv, evalarg, TRUE);
3249 		}
3250 		else
3251 		    ret = NOTDONE;
3252 		break;
3253 
3254     /*
3255      * Lambda: {arg, arg -> expr}
3256      * Dictionary: {'key': val, 'key': val}
3257      */
3258     case '{':	ret = get_lambda_tv(arg, rettv, evalarg);
3259 		if (ret == NOTDONE)
3260 		    ret = eval_dict(arg, rettv, evalarg, FALSE);
3261 		break;
3262 
3263     /*
3264      * Option value: &name
3265      */
3266     case '&':	ret = eval_option(arg, rettv, evaluate);
3267 		break;
3268 
3269     /*
3270      * Environment variable: $VAR.
3271      */
3272     case '$':	ret = eval_env_var(arg, rettv, evaluate);
3273 		break;
3274 
3275     /*
3276      * Register contents: @r.
3277      */
3278     case '@':	++*arg;
3279 		if (evaluate)
3280 		{
3281 		    rettv->v_type = VAR_STRING;
3282 		    rettv->vval.v_string = get_reg_contents(**arg,
3283 							    GREG_EXPR_SRC);
3284 		}
3285 		if (**arg != NUL)
3286 		    ++*arg;
3287 		break;
3288 
3289     /*
3290      * nested expression: (expression).
3291      */
3292     case '(':	{
3293 		    *arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3294 		    ret = eval1(arg, rettv, evalarg);	// recursive!
3295 
3296 		    *arg = skipwhite_and_linebreak(*arg, evalarg);
3297 		    if (**arg == ')')
3298 			++*arg;
3299 		    else if (ret == OK)
3300 		    {
3301 			emsg(_(e_missing_close));
3302 			clear_tv(rettv);
3303 			ret = FAIL;
3304 		    }
3305 		}
3306 		break;
3307 
3308     default:	ret = NOTDONE;
3309 		break;
3310     }
3311 
3312     if (ret == NOTDONE)
3313     {
3314 	/*
3315 	 * Must be a variable or function name.
3316 	 * Can also be a curly-braces kind of name: {expr}.
3317 	 */
3318 	s = *arg;
3319 	len = get_name_len(arg, &alias, evaluate, TRUE);
3320 	if (alias != NULL)
3321 	    s = alias;
3322 
3323 	if (len <= 0)
3324 	    ret = FAIL;
3325 	else
3326 	{
3327 	    int	    flags = evalarg == NULL ? 0 : evalarg->eval_flags;
3328 
3329 	    if ((in_vim9script() ? **arg : *skipwhite(*arg)) == '(')
3330 	    {
3331 		// "name(..."  recursive!
3332 		*arg = skipwhite(*arg);
3333 		ret = eval_func(arg, evalarg, s, len, rettv, flags, NULL);
3334 	    }
3335 	    else if (flags & EVAL_CONSTANT)
3336 		ret = FAIL;
3337 	    else if (evaluate)
3338 	    {
3339 		// get the value of "true", "false" or a variable
3340 		if (len == 4 && in_vim9script() && STRNCMP(s, "true", 4) == 0)
3341 		{
3342 		    rettv->v_type = VAR_BOOL;
3343 		    rettv->vval.v_number = VVAL_TRUE;
3344 		    ret = OK;
3345 		}
3346 		else if (len == 5 && in_vim9script()
3347 						&& STRNCMP(s, "false", 4) == 0)
3348 		{
3349 		    rettv->v_type = VAR_BOOL;
3350 		    rettv->vval.v_number = VVAL_FALSE;
3351 		    ret = OK;
3352 		}
3353 		else
3354 		    ret = eval_variable(s, len, rettv, NULL, TRUE, FALSE);
3355 	    }
3356 	    else
3357 	    {
3358 		// skip the name
3359 		check_vars(s, len);
3360 		ret = OK;
3361 	    }
3362 	}
3363 	vim_free(alias);
3364     }
3365 
3366     // Handle following '[', '(' and '.' for expr[expr], expr.name,
3367     // expr(expr), expr->name(expr)
3368     if (ret == OK)
3369 	ret = handle_subscript(arg, rettv, evalarg, TRUE);
3370 
3371     /*
3372      * Apply logical NOT and unary '-', from right to left, ignore '+'.
3373      */
3374     if (ret == OK && evaluate && end_leader > start_leader)
3375 	ret = eval7_leader(rettv, FALSE, start_leader, &end_leader);
3376     return ret;
3377 }
3378 
3379 /*
3380  * Apply the leading "!" and "-" before an eval7 expression to "rettv".
3381  * When "numeric_only" is TRUE only handle "+" and "-".
3382  * Adjusts "end_leaderp" until it is at "start_leader".
3383  */
3384     static int
3385 eval7_leader(
3386 	typval_T    *rettv,
3387 	int	    numeric_only,
3388 	char_u	    *start_leader,
3389 	char_u	    **end_leaderp)
3390 {
3391     char_u	*end_leader = *end_leaderp;
3392     int		ret = OK;
3393     int		error = FALSE;
3394     varnumber_T val = 0;
3395     vartype_T	type = rettv->v_type;
3396 #ifdef FEAT_FLOAT
3397     float_T	    f = 0.0;
3398 
3399     if (rettv->v_type == VAR_FLOAT)
3400 	f = rettv->vval.v_float;
3401     else
3402 #endif
3403     {
3404 	while (VIM_ISWHITE(end_leader[-1]))
3405 	    --end_leader;
3406 	if (in_vim9script() && end_leader[-1] == '!')
3407 	    val = tv2bool(rettv);
3408 	else
3409 	    val = tv_get_number_chk(rettv, &error);
3410     }
3411     if (error)
3412     {
3413 	clear_tv(rettv);
3414 	ret = FAIL;
3415     }
3416     else
3417     {
3418 	while (end_leader > start_leader)
3419 	{
3420 	    --end_leader;
3421 	    if (*end_leader == '!')
3422 	    {
3423 		if (numeric_only)
3424 		{
3425 		    ++end_leader;
3426 		    break;
3427 		}
3428 #ifdef FEAT_FLOAT
3429 		if (rettv->v_type == VAR_FLOAT)
3430 		    f = !f;
3431 		else
3432 #endif
3433 		{
3434 		    val = !val;
3435 		    type = VAR_BOOL;
3436 		}
3437 	    }
3438 	    else if (*end_leader == '-')
3439 	    {
3440 #ifdef FEAT_FLOAT
3441 		if (rettv->v_type == VAR_FLOAT)
3442 		    f = -f;
3443 		else
3444 #endif
3445 		{
3446 		    val = -val;
3447 		    type = VAR_NUMBER;
3448 		}
3449 	    }
3450 	}
3451 #ifdef FEAT_FLOAT
3452 	if (rettv->v_type == VAR_FLOAT)
3453 	{
3454 	    clear_tv(rettv);
3455 	    rettv->vval.v_float = f;
3456 	}
3457 	else
3458 #endif
3459 	{
3460 	    clear_tv(rettv);
3461 	    if (in_vim9script())
3462 		rettv->v_type = type;
3463 	    else
3464 		rettv->v_type = VAR_NUMBER;
3465 	    rettv->vval.v_number = val;
3466 	}
3467     }
3468     *end_leaderp = end_leader;
3469     return ret;
3470 }
3471 
3472 /*
3473  * Call the function referred to in "rettv".
3474  */
3475     static int
3476 call_func_rettv(
3477 	char_u	    **arg,
3478 	evalarg_T   *evalarg,
3479 	typval_T    *rettv,
3480 	int	    evaluate,
3481 	dict_T	    *selfdict,
3482 	typval_T    *basetv)
3483 {
3484     partial_T	*pt = NULL;
3485     funcexe_T	funcexe;
3486     typval_T	functv;
3487     char_u	*s;
3488     int		ret;
3489 
3490     // need to copy the funcref so that we can clear rettv
3491     if (evaluate)
3492     {
3493 	functv = *rettv;
3494 	rettv->v_type = VAR_UNKNOWN;
3495 
3496 	// Invoke the function.  Recursive!
3497 	if (functv.v_type == VAR_PARTIAL)
3498 	{
3499 	    pt = functv.vval.v_partial;
3500 	    s = partial_name(pt);
3501 	}
3502 	else
3503 	    s = functv.vval.v_string;
3504     }
3505     else
3506 	s = (char_u *)"";
3507 
3508     CLEAR_FIELD(funcexe);
3509     funcexe.firstline = curwin->w_cursor.lnum;
3510     funcexe.lastline = curwin->w_cursor.lnum;
3511     funcexe.evaluate = evaluate;
3512     funcexe.partial = pt;
3513     funcexe.selfdict = selfdict;
3514     funcexe.basetv = basetv;
3515     ret = get_func_tv(s, -1, rettv, arg, evalarg, &funcexe);
3516 
3517     // Clear the funcref afterwards, so that deleting it while
3518     // evaluating the arguments is possible (see test55).
3519     if (evaluate)
3520 	clear_tv(&functv);
3521 
3522     return ret;
3523 }
3524 
3525 /*
3526  * Evaluate "->method()".
3527  * "*arg" points to the '-'.
3528  * Returns FAIL or OK. "*arg" is advanced to after the ')'.
3529  */
3530     static int
3531 eval_lambda(
3532     char_u	**arg,
3533     typval_T	*rettv,
3534     evalarg_T	*evalarg,
3535     int		verbose)	// give error messages
3536 {
3537     int		evaluate = evalarg != NULL
3538 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3539     typval_T	base = *rettv;
3540     int		ret;
3541 
3542     // Skip over the ->.
3543     *arg += 2;
3544     rettv->v_type = VAR_UNKNOWN;
3545 
3546     ret = get_lambda_tv(arg, rettv, evalarg);
3547     if (ret != OK)
3548 	return FAIL;
3549     else if (**arg != '(')
3550     {
3551 	if (verbose)
3552 	{
3553 	    if (*skipwhite(*arg) == '(')
3554 		emsg(_(e_nowhitespace));
3555 	    else
3556 		semsg(_(e_missing_paren), "lambda");
3557 	}
3558 	clear_tv(rettv);
3559 	ret = FAIL;
3560     }
3561     else
3562 	ret = call_func_rettv(arg, evalarg, rettv, evaluate, NULL, &base);
3563 
3564     // Clear the funcref afterwards, so that deleting it while
3565     // evaluating the arguments is possible (see test55).
3566     if (evaluate)
3567 	clear_tv(&base);
3568 
3569     return ret;
3570 }
3571 
3572 /*
3573  * Evaluate "->method()".
3574  * "*arg" points to the '-'.
3575  * Returns FAIL or OK. "*arg" is advanced to after the ')'.
3576  */
3577     static int
3578 eval_method(
3579     char_u	**arg,
3580     typval_T	*rettv,
3581     evalarg_T	*evalarg,
3582     int		verbose)	// give error messages
3583 {
3584     char_u	*name;
3585     long	len;
3586     char_u	*alias;
3587     typval_T	base = *rettv;
3588     int		ret;
3589     int		evaluate = evalarg != NULL
3590 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3591 
3592     // Skip over the ->.
3593     *arg += 2;
3594     rettv->v_type = VAR_UNKNOWN;
3595 
3596     name = *arg;
3597     len = get_name_len(arg, &alias, evaluate, TRUE);
3598     if (alias != NULL)
3599 	name = alias;
3600 
3601     if (len <= 0)
3602     {
3603 	if (verbose)
3604 	    emsg(_("E260: Missing name after ->"));
3605 	ret = FAIL;
3606     }
3607     else
3608     {
3609 	*arg = skipwhite(*arg);
3610 	if (**arg != '(')
3611 	{
3612 	    if (verbose)
3613 		semsg(_(e_missing_paren), name);
3614 	    ret = FAIL;
3615 	}
3616 	else if (VIM_ISWHITE((*arg)[-1]))
3617 	{
3618 	    if (verbose)
3619 		emsg(_(e_nowhitespace));
3620 	    ret = FAIL;
3621 	}
3622 	else
3623 	    ret = eval_func(arg, evalarg, name, len, rettv,
3624 					  evaluate ? EVAL_EVALUATE : 0, &base);
3625     }
3626 
3627     // Clear the funcref afterwards, so that deleting it while
3628     // evaluating the arguments is possible (see test55).
3629     if (evaluate)
3630 	clear_tv(&base);
3631 
3632     return ret;
3633 }
3634 
3635 /*
3636  * Evaluate an "[expr]" or "[expr:expr]" index.  Also "dict.key".
3637  * "*arg" points to the '[' or '.'.
3638  * Returns FAIL or OK. "*arg" is advanced to after the ']'.
3639  */
3640     static int
3641 eval_index(
3642     char_u	**arg,
3643     typval_T	*rettv,
3644     evalarg_T	*evalarg,
3645     int		verbose)	// give error messages
3646 {
3647     int		evaluate = evalarg != NULL
3648 				      && (evalarg->eval_flags & EVAL_EVALUATE);
3649     int		empty1 = FALSE, empty2 = FALSE;
3650     typval_T	var1, var2;
3651     int		range = FALSE;
3652     char_u	*key = NULL;
3653     int		keylen = -1;
3654 
3655     if (check_can_index(rettv, evaluate, verbose) == FAIL)
3656 	return FAIL;
3657 
3658     init_tv(&var1);
3659     init_tv(&var2);
3660     if (**arg == '.')
3661     {
3662 	/*
3663 	 * dict.name
3664 	 */
3665 	key = *arg + 1;
3666 	for (keylen = 0; eval_isdictc(key[keylen]); ++keylen)
3667 	    ;
3668 	if (keylen == 0)
3669 	    return FAIL;
3670 	*arg = key + keylen;
3671     }
3672     else
3673     {
3674 	/*
3675 	 * something[idx]
3676 	 *
3677 	 * Get the (first) variable from inside the [].
3678 	 */
3679 	*arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3680 	if (**arg == ':')
3681 	    empty1 = TRUE;
3682 	else if (eval1(arg, &var1, evalarg) == FAIL)	// recursive!
3683 	    return FAIL;
3684 	else if (evaluate && tv_get_string_chk(&var1) == NULL)
3685 	{
3686 	    // not a number or string
3687 	    clear_tv(&var1);
3688 	    return FAIL;
3689 	}
3690 
3691 	/*
3692 	 * Get the second variable from inside the [:].
3693 	 */
3694 	*arg = skipwhite_and_linebreak(*arg, evalarg);
3695 	if (**arg == ':')
3696 	{
3697 	    range = TRUE;
3698 	    *arg = skipwhite_and_linebreak(*arg + 1, evalarg);
3699 	    if (**arg == ']')
3700 		empty2 = TRUE;
3701 	    else if (eval1(arg, &var2, evalarg) == FAIL)	// recursive!
3702 	    {
3703 		if (!empty1)
3704 		    clear_tv(&var1);
3705 		return FAIL;
3706 	    }
3707 	    else if (evaluate && tv_get_string_chk(&var2) == NULL)
3708 	    {
3709 		// not a number or string
3710 		if (!empty1)
3711 		    clear_tv(&var1);
3712 		clear_tv(&var2);
3713 		return FAIL;
3714 	    }
3715 	}
3716 
3717 	// Check for the ']'.
3718 	*arg = skipwhite_and_linebreak(*arg, evalarg);
3719 	if (**arg != ']')
3720 	{
3721 	    if (verbose)
3722 		emsg(_(e_missbrac));
3723 	    clear_tv(&var1);
3724 	    if (range)
3725 		clear_tv(&var2);
3726 	    return FAIL;
3727 	}
3728 	*arg = *arg + 1;	// skip over the ']'
3729     }
3730 
3731     if (evaluate)
3732     {
3733 	int res = eval_index_inner(rettv, range,
3734 		empty1 ? NULL : &var1, empty2 ? NULL : &var2,
3735 		key, keylen, verbose);
3736 	if (!empty1)
3737 	    clear_tv(&var1);
3738 	if (range)
3739 	    clear_tv(&var2);
3740 	return res;
3741     }
3742     return OK;
3743 }
3744 
3745 /*
3746  * Check if "rettv" can have an [index] or [sli:ce]
3747  */
3748     int
3749 check_can_index(typval_T *rettv, int evaluate, int verbose)
3750 {
3751     switch (rettv->v_type)
3752     {
3753 	case VAR_FUNC:
3754 	case VAR_PARTIAL:
3755 	    if (verbose)
3756 		emsg(_("E695: Cannot index a Funcref"));
3757 	    return FAIL;
3758 	case VAR_FLOAT:
3759 #ifdef FEAT_FLOAT
3760 	    if (verbose)
3761 		emsg(_(e_float_as_string));
3762 	    return FAIL;
3763 #endif
3764 	case VAR_BOOL:
3765 	case VAR_SPECIAL:
3766 	case VAR_JOB:
3767 	case VAR_CHANNEL:
3768 	    if (verbose)
3769 		emsg(_(e_cannot_index_special_variable));
3770 	    return FAIL;
3771 	case VAR_UNKNOWN:
3772 	case VAR_ANY:
3773 	case VAR_VOID:
3774 	    if (evaluate)
3775 	    {
3776 		emsg(_(e_cannot_index_special_variable));
3777 		return FAIL;
3778 	    }
3779 	    // FALLTHROUGH
3780 
3781 	case VAR_STRING:
3782 	case VAR_LIST:
3783 	case VAR_DICT:
3784 	case VAR_BLOB:
3785 	    break;
3786 	case VAR_NUMBER:
3787 	    if (in_vim9script())
3788 		emsg(_(e_cannot_index_number));
3789 	    break;
3790     }
3791     return OK;
3792 }
3793 
3794 /*
3795  * Apply index or range to "rettv".
3796  * "var1" is the first index, NULL for [:expr].
3797  * "var2" is the second index, NULL for [expr] and [expr: ]
3798  * Alternatively, "key" is not NULL, then key[keylen] is the dict index.
3799  */
3800     int
3801 eval_index_inner(
3802 	typval_T    *rettv,
3803 	int	    is_range,
3804 	typval_T    *var1,
3805 	typval_T    *var2,
3806 	char_u	    *key,
3807 	int	    keylen,
3808 	int	    verbose)
3809 {
3810     long	n1, n2 = 0;
3811     long	len;
3812 
3813     n1 = 0;
3814     if (var1 != NULL && rettv->v_type != VAR_DICT)
3815 	n1 = tv_get_number(var1);
3816 
3817     if (is_range)
3818     {
3819 	if (rettv->v_type == VAR_DICT)
3820 	{
3821 	    if (verbose)
3822 		emsg(_(e_cannot_slice_dictionary));
3823 	    return FAIL;
3824 	}
3825 	if (var2 == NULL)
3826 	    n2 = -1;
3827 	else
3828 	    n2 = tv_get_number(var2);
3829     }
3830 
3831     switch (rettv->v_type)
3832     {
3833 	case VAR_UNKNOWN:
3834 	case VAR_ANY:
3835 	case VAR_VOID:
3836 	case VAR_FUNC:
3837 	case VAR_PARTIAL:
3838 	case VAR_FLOAT:
3839 	case VAR_BOOL:
3840 	case VAR_SPECIAL:
3841 	case VAR_JOB:
3842 	case VAR_CHANNEL:
3843 	    break; // not evaluating, skipping over subscript
3844 
3845 	case VAR_NUMBER:
3846 	case VAR_STRING:
3847 	    {
3848 		char_u	*s = tv_get_string(rettv);
3849 
3850 		len = (long)STRLEN(s);
3851 		if (in_vim9script())
3852 		{
3853 		    if (is_range)
3854 			s = string_slice(s, n1, n2);
3855 		    else
3856 			s = char_from_string(s, n1);
3857 		}
3858 		else if (is_range)
3859 		{
3860 		    // The resulting variable is a substring.  If the indexes
3861 		    // are out of range the result is empty.
3862 		    if (n1 < 0)
3863 		    {
3864 			n1 = len + n1;
3865 			if (n1 < 0)
3866 			    n1 = 0;
3867 		    }
3868 		    if (n2 < 0)
3869 			n2 = len + n2;
3870 		    else if (n2 >= len)
3871 			n2 = len;
3872 		    if (n1 >= len || n2 < 0 || n1 > n2)
3873 			s = NULL;
3874 		    else
3875 			s = vim_strnsave(s + n1, n2 - n1 + 1);
3876 		}
3877 		else
3878 		{
3879 		    // The resulting variable is a string of a single
3880 		    // character.  If the index is too big or negative the
3881 		    // result is empty.
3882 		    if (n1 >= len || n1 < 0)
3883 			s = NULL;
3884 		    else
3885 			s = vim_strnsave(s + n1, 1);
3886 		}
3887 		clear_tv(rettv);
3888 		rettv->v_type = VAR_STRING;
3889 		rettv->vval.v_string = s;
3890 	    }
3891 	    break;
3892 
3893 	case VAR_BLOB:
3894 	    len = blob_len(rettv->vval.v_blob);
3895 	    if (is_range)
3896 	    {
3897 		// The resulting variable is a sub-blob.  If the indexes
3898 		// are out of range the result is empty.
3899 		if (n1 < 0)
3900 		{
3901 		    n1 = len + n1;
3902 		    if (n1 < 0)
3903 			n1 = 0;
3904 		}
3905 		if (n2 < 0)
3906 		    n2 = len + n2;
3907 		else if (n2 >= len)
3908 		    n2 = len - 1;
3909 		if (n1 >= len || n2 < 0 || n1 > n2)
3910 		{
3911 		    clear_tv(rettv);
3912 		    rettv->v_type = VAR_BLOB;
3913 		    rettv->vval.v_blob = NULL;
3914 		}
3915 		else
3916 		{
3917 		    blob_T  *blob = blob_alloc();
3918 		    long    i;
3919 
3920 		    if (blob != NULL)
3921 		    {
3922 			if (ga_grow(&blob->bv_ga, n2 - n1 + 1) == FAIL)
3923 			{
3924 			    blob_free(blob);
3925 			    return FAIL;
3926 			}
3927 			blob->bv_ga.ga_len = n2 - n1 + 1;
3928 			for (i = n1; i <= n2; i++)
3929 			    blob_set(blob, i - n1,
3930 					  blob_get(rettv->vval.v_blob, i));
3931 
3932 			clear_tv(rettv);
3933 			rettv_blob_set(rettv, blob);
3934 		    }
3935 		}
3936 	    }
3937 	    else
3938 	    {
3939 		// The resulting variable is a byte value.
3940 		// If the index is too big or negative that is an error.
3941 		if (n1 < 0)
3942 		    n1 = len + n1;
3943 		if (n1 < len && n1 >= 0)
3944 		{
3945 		    int v = blob_get(rettv->vval.v_blob, n1);
3946 
3947 		    clear_tv(rettv);
3948 		    rettv->v_type = VAR_NUMBER;
3949 		    rettv->vval.v_number = v;
3950 		}
3951 		else
3952 		    semsg(_(e_blobidx), n1);
3953 	    }
3954 	    break;
3955 
3956 	case VAR_LIST:
3957 	    if (var1 == NULL)
3958 		n1 = 0;
3959 	    if (var2 == NULL)
3960 		n2 = -1;
3961 	    if (list_slice_or_index(rettv->vval.v_list,
3962 				    is_range, n1, n2, rettv, verbose) == FAIL)
3963 		return FAIL;
3964 	    break;
3965 
3966 	case VAR_DICT:
3967 	    {
3968 		dictitem_T	*item;
3969 		typval_T	tmp;
3970 
3971 		if (key == NULL)
3972 		{
3973 		    key = tv_get_string_chk(var1);
3974 		    if (key == NULL)
3975 			return FAIL;
3976 		}
3977 
3978 		item = dict_find(rettv->vval.v_dict, key, (int)keylen);
3979 
3980 		if (item == NULL && verbose)
3981 		    semsg(_(e_dictkey), key);
3982 		if (item == NULL)
3983 		    return FAIL;
3984 
3985 		copy_tv(&item->di_tv, &tmp);
3986 		clear_tv(rettv);
3987 		*rettv = tmp;
3988 	    }
3989 	    break;
3990     }
3991     return OK;
3992 }
3993 
3994 /*
3995  * Return the function name of partial "pt".
3996  */
3997     char_u *
3998 partial_name(partial_T *pt)
3999 {
4000     if (pt->pt_name != NULL)
4001 	return pt->pt_name;
4002     if (pt->pt_func != NULL)
4003 	return pt->pt_func->uf_name;
4004     return (char_u *)"";
4005 }
4006 
4007     static void
4008 partial_free(partial_T *pt)
4009 {
4010     int i;
4011 
4012     for (i = 0; i < pt->pt_argc; ++i)
4013 	clear_tv(&pt->pt_argv[i]);
4014     vim_free(pt->pt_argv);
4015     dict_unref(pt->pt_dict);
4016     if (pt->pt_name != NULL)
4017     {
4018 	func_unref(pt->pt_name);
4019 	vim_free(pt->pt_name);
4020     }
4021     else
4022 	func_ptr_unref(pt->pt_func);
4023 
4024     // Decrease the reference count for the context of a closure.  If down
4025     // to the minimum it may be time to free it.
4026     if (pt->pt_funcstack != NULL)
4027     {
4028 	--pt->pt_funcstack->fs_refcount;
4029 	funcstack_check_refcount(pt->pt_funcstack);
4030     }
4031 
4032     vim_free(pt);
4033 }
4034 
4035 /*
4036  * Unreference a closure: decrement the reference count and free it when it
4037  * becomes zero.
4038  */
4039     void
4040 partial_unref(partial_T *pt)
4041 {
4042     if (pt != NULL)
4043     {
4044 	if (--pt->pt_refcount <= 0)
4045 	    partial_free(pt);
4046 
4047 	// If the reference count goes down to one, the funcstack may be the
4048 	// only reference and can be freed if no other partials reference it.
4049 	else if (pt->pt_refcount == 1 && pt->pt_funcstack != NULL)
4050 	    funcstack_check_refcount(pt->pt_funcstack);
4051     }
4052 }
4053 
4054 /*
4055  * Return the next (unique) copy ID.
4056  * Used for serializing nested structures.
4057  */
4058     int
4059 get_copyID(void)
4060 {
4061     current_copyID += COPYID_INC;
4062     return current_copyID;
4063 }
4064 
4065 /*
4066  * Garbage collection for lists and dictionaries.
4067  *
4068  * We use reference counts to be able to free most items right away when they
4069  * are no longer used.  But for composite items it's possible that it becomes
4070  * unused while the reference count is > 0: When there is a recursive
4071  * reference.  Example:
4072  *	:let l = [1, 2, 3]
4073  *	:let d = {9: l}
4074  *	:let l[1] = d
4075  *
4076  * Since this is quite unusual we handle this with garbage collection: every
4077  * once in a while find out which lists and dicts are not referenced from any
4078  * variable.
4079  *
4080  * Here is a good reference text about garbage collection (refers to Python
4081  * but it applies to all reference-counting mechanisms):
4082  *	http://python.ca/nas/python/gc/
4083  */
4084 
4085 /*
4086  * Do garbage collection for lists and dicts.
4087  * When "testing" is TRUE this is called from test_garbagecollect_now().
4088  * Return TRUE if some memory was freed.
4089  */
4090     int
4091 garbage_collect(int testing)
4092 {
4093     int		copyID;
4094     int		abort = FALSE;
4095     buf_T	*buf;
4096     win_T	*wp;
4097     int		did_free = FALSE;
4098     tabpage_T	*tp;
4099 
4100     if (!testing)
4101     {
4102 	// Only do this once.
4103 	want_garbage_collect = FALSE;
4104 	may_garbage_collect = FALSE;
4105 	garbage_collect_at_exit = FALSE;
4106     }
4107 
4108     // The execution stack can grow big, limit the size.
4109     if (exestack.ga_maxlen - exestack.ga_len > 500)
4110     {
4111 	size_t	new_len;
4112 	char_u	*pp;
4113 	int	n;
4114 
4115 	// Keep 150% of the current size, with a minimum of the growth size.
4116 	n = exestack.ga_len / 2;
4117 	if (n < exestack.ga_growsize)
4118 	    n = exestack.ga_growsize;
4119 
4120 	// Don't make it bigger though.
4121 	if (exestack.ga_len + n < exestack.ga_maxlen)
4122 	{
4123 	    new_len = exestack.ga_itemsize * (exestack.ga_len + n);
4124 	    pp = vim_realloc(exestack.ga_data, new_len);
4125 	    if (pp == NULL)
4126 		return FAIL;
4127 	    exestack.ga_maxlen = exestack.ga_len + n;
4128 	    exestack.ga_data = pp;
4129 	}
4130     }
4131 
4132     // We advance by two because we add one for items referenced through
4133     // previous_funccal.
4134     copyID = get_copyID();
4135 
4136     /*
4137      * 1. Go through all accessible variables and mark all lists and dicts
4138      *    with copyID.
4139      */
4140 
4141     // Don't free variables in the previous_funccal list unless they are only
4142     // referenced through previous_funccal.  This must be first, because if
4143     // the item is referenced elsewhere the funccal must not be freed.
4144     abort = abort || set_ref_in_previous_funccal(copyID);
4145 
4146     // script-local variables
4147     abort = abort || garbage_collect_scriptvars(copyID);
4148 
4149     // buffer-local variables
4150     FOR_ALL_BUFFERS(buf)
4151 	abort = abort || set_ref_in_item(&buf->b_bufvar.di_tv, copyID,
4152 								  NULL, NULL);
4153 
4154     // window-local variables
4155     FOR_ALL_TAB_WINDOWS(tp, wp)
4156 	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
4157 								  NULL, NULL);
4158     if (aucmd_win != NULL)
4159 	abort = abort || set_ref_in_item(&aucmd_win->w_winvar.di_tv, copyID,
4160 								  NULL, NULL);
4161 #ifdef FEAT_PROP_POPUP
4162     FOR_ALL_POPUPWINS(wp)
4163 	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
4164 								  NULL, NULL);
4165     FOR_ALL_TABPAGES(tp)
4166 	FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
4167 		abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
4168 								  NULL, NULL);
4169 #endif
4170 
4171     // tabpage-local variables
4172     FOR_ALL_TABPAGES(tp)
4173 	abort = abort || set_ref_in_item(&tp->tp_winvar.di_tv, copyID,
4174 								  NULL, NULL);
4175     // global variables
4176     abort = abort || garbage_collect_globvars(copyID);
4177 
4178     // function-local variables
4179     abort = abort || set_ref_in_call_stack(copyID);
4180 
4181     // named functions (matters for closures)
4182     abort = abort || set_ref_in_functions(copyID);
4183 
4184     // function call arguments, if v:testing is set.
4185     abort = abort || set_ref_in_func_args(copyID);
4186 
4187     // v: vars
4188     abort = abort || garbage_collect_vimvars(copyID);
4189 
4190     // callbacks in buffers
4191     abort = abort || set_ref_in_buffers(copyID);
4192 
4193 #ifdef FEAT_LUA
4194     abort = abort || set_ref_in_lua(copyID);
4195 #endif
4196 
4197 #ifdef FEAT_PYTHON
4198     abort = abort || set_ref_in_python(copyID);
4199 #endif
4200 
4201 #ifdef FEAT_PYTHON3
4202     abort = abort || set_ref_in_python3(copyID);
4203 #endif
4204 
4205 #ifdef FEAT_JOB_CHANNEL
4206     abort = abort || set_ref_in_channel(copyID);
4207     abort = abort || set_ref_in_job(copyID);
4208 #endif
4209 #ifdef FEAT_NETBEANS_INTG
4210     abort = abort || set_ref_in_nb_channel(copyID);
4211 #endif
4212 
4213 #ifdef FEAT_TIMERS
4214     abort = abort || set_ref_in_timer(copyID);
4215 #endif
4216 
4217 #ifdef FEAT_QUICKFIX
4218     abort = abort || set_ref_in_quickfix(copyID);
4219 #endif
4220 
4221 #ifdef FEAT_TERMINAL
4222     abort = abort || set_ref_in_term(copyID);
4223 #endif
4224 
4225 #ifdef FEAT_PROP_POPUP
4226     abort = abort || set_ref_in_popups(copyID);
4227 #endif
4228 
4229     if (!abort)
4230     {
4231 	/*
4232 	 * 2. Free lists and dictionaries that are not referenced.
4233 	 */
4234 	did_free = free_unref_items(copyID);
4235 
4236 	/*
4237 	 * 3. Check if any funccal can be freed now.
4238 	 *    This may call us back recursively.
4239 	 */
4240 	free_unref_funccal(copyID, testing);
4241     }
4242     else if (p_verbose > 0)
4243     {
4244 	verb_msg(_("Not enough memory to set references, garbage collection aborted!"));
4245     }
4246 
4247     return did_free;
4248 }
4249 
4250 /*
4251  * Free lists, dictionaries, channels and jobs that are no longer referenced.
4252  */
4253     static int
4254 free_unref_items(int copyID)
4255 {
4256     int		did_free = FALSE;
4257 
4258     // Let all "free" functions know that we are here.  This means no
4259     // dictionaries, lists, channels or jobs are to be freed, because we will
4260     // do that here.
4261     in_free_unref_items = TRUE;
4262 
4263     /*
4264      * PASS 1: free the contents of the items.  We don't free the items
4265      * themselves yet, so that it is possible to decrement refcount counters
4266      */
4267 
4268     // Go through the list of dicts and free items without the copyID.
4269     did_free |= dict_free_nonref(copyID);
4270 
4271     // Go through the list of lists and free items without the copyID.
4272     did_free |= list_free_nonref(copyID);
4273 
4274 #ifdef FEAT_JOB_CHANNEL
4275     // Go through the list of jobs and free items without the copyID. This
4276     // must happen before doing channels, because jobs refer to channels, but
4277     // the reference from the channel to the job isn't tracked.
4278     did_free |= free_unused_jobs_contents(copyID, COPYID_MASK);
4279 
4280     // Go through the list of channels and free items without the copyID.
4281     did_free |= free_unused_channels_contents(copyID, COPYID_MASK);
4282 #endif
4283 
4284     /*
4285      * PASS 2: free the items themselves.
4286      */
4287     dict_free_items(copyID);
4288     list_free_items(copyID);
4289 
4290 #ifdef FEAT_JOB_CHANNEL
4291     // Go through the list of jobs and free items without the copyID. This
4292     // must happen before doing channels, because jobs refer to channels, but
4293     // the reference from the channel to the job isn't tracked.
4294     free_unused_jobs(copyID, COPYID_MASK);
4295 
4296     // Go through the list of channels and free items without the copyID.
4297     free_unused_channels(copyID, COPYID_MASK);
4298 #endif
4299 
4300     in_free_unref_items = FALSE;
4301 
4302     return did_free;
4303 }
4304 
4305 /*
4306  * Mark all lists and dicts referenced through hashtab "ht" with "copyID".
4307  * "list_stack" is used to add lists to be marked.  Can be NULL.
4308  *
4309  * Returns TRUE if setting references failed somehow.
4310  */
4311     int
4312 set_ref_in_ht(hashtab_T *ht, int copyID, list_stack_T **list_stack)
4313 {
4314     int		todo;
4315     int		abort = FALSE;
4316     hashitem_T	*hi;
4317     hashtab_T	*cur_ht;
4318     ht_stack_T	*ht_stack = NULL;
4319     ht_stack_T	*tempitem;
4320 
4321     cur_ht = ht;
4322     for (;;)
4323     {
4324 	if (!abort)
4325 	{
4326 	    // Mark each item in the hashtab.  If the item contains a hashtab
4327 	    // it is added to ht_stack, if it contains a list it is added to
4328 	    // list_stack.
4329 	    todo = (int)cur_ht->ht_used;
4330 	    for (hi = cur_ht->ht_array; todo > 0; ++hi)
4331 		if (!HASHITEM_EMPTY(hi))
4332 		{
4333 		    --todo;
4334 		    abort = abort || set_ref_in_item(&HI2DI(hi)->di_tv, copyID,
4335 						       &ht_stack, list_stack);
4336 		}
4337 	}
4338 
4339 	if (ht_stack == NULL)
4340 	    break;
4341 
4342 	// take an item from the stack
4343 	cur_ht = ht_stack->ht;
4344 	tempitem = ht_stack;
4345 	ht_stack = ht_stack->prev;
4346 	free(tempitem);
4347     }
4348 
4349     return abort;
4350 }
4351 
4352 /*
4353  * Mark a dict and its items with "copyID".
4354  * Returns TRUE if setting references failed somehow.
4355  */
4356     int
4357 set_ref_in_dict(dict_T *d, int copyID)
4358 {
4359     if (d != NULL && d->dv_copyID != copyID)
4360     {
4361 	d->dv_copyID = copyID;
4362 	return set_ref_in_ht(&d->dv_hashtab, copyID, NULL);
4363     }
4364     return FALSE;
4365 }
4366 
4367 /*
4368  * Mark a list and its items with "copyID".
4369  * Returns TRUE if setting references failed somehow.
4370  */
4371     int
4372 set_ref_in_list(list_T *ll, int copyID)
4373 {
4374     if (ll != NULL && ll->lv_copyID != copyID)
4375     {
4376 	ll->lv_copyID = copyID;
4377 	return set_ref_in_list_items(ll, copyID, NULL);
4378     }
4379     return FALSE;
4380 }
4381 
4382 /*
4383  * Mark all lists and dicts referenced through list "l" with "copyID".
4384  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
4385  *
4386  * Returns TRUE if setting references failed somehow.
4387  */
4388     int
4389 set_ref_in_list_items(list_T *l, int copyID, ht_stack_T **ht_stack)
4390 {
4391     listitem_T	 *li;
4392     int		 abort = FALSE;
4393     list_T	 *cur_l;
4394     list_stack_T *list_stack = NULL;
4395     list_stack_T *tempitem;
4396 
4397     cur_l = l;
4398     for (;;)
4399     {
4400 	if (!abort && cur_l->lv_first != &range_list_item)
4401 	    // Mark each item in the list.  If the item contains a hashtab
4402 	    // it is added to ht_stack, if it contains a list it is added to
4403 	    // list_stack.
4404 	    for (li = cur_l->lv_first; !abort && li != NULL; li = li->li_next)
4405 		abort = abort || set_ref_in_item(&li->li_tv, copyID,
4406 						       ht_stack, &list_stack);
4407 	if (list_stack == NULL)
4408 	    break;
4409 
4410 	// take an item from the stack
4411 	cur_l = list_stack->list;
4412 	tempitem = list_stack;
4413 	list_stack = list_stack->prev;
4414 	free(tempitem);
4415     }
4416 
4417     return abort;
4418 }
4419 
4420 /*
4421  * Mark all lists and dicts referenced through typval "tv" with "copyID".
4422  * "list_stack" is used to add lists to be marked.  Can be NULL.
4423  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
4424  *
4425  * Returns TRUE if setting references failed somehow.
4426  */
4427     int
4428 set_ref_in_item(
4429     typval_T	    *tv,
4430     int		    copyID,
4431     ht_stack_T	    **ht_stack,
4432     list_stack_T    **list_stack)
4433 {
4434     int		abort = FALSE;
4435 
4436     if (tv->v_type == VAR_DICT)
4437     {
4438 	dict_T	*dd = tv->vval.v_dict;
4439 
4440 	if (dd != NULL && dd->dv_copyID != copyID)
4441 	{
4442 	    // Didn't see this dict yet.
4443 	    dd->dv_copyID = copyID;
4444 	    if (ht_stack == NULL)
4445 	    {
4446 		abort = set_ref_in_ht(&dd->dv_hashtab, copyID, list_stack);
4447 	    }
4448 	    else
4449 	    {
4450 		ht_stack_T *newitem = ALLOC_ONE(ht_stack_T);
4451 
4452 		if (newitem == NULL)
4453 		    abort = TRUE;
4454 		else
4455 		{
4456 		    newitem->ht = &dd->dv_hashtab;
4457 		    newitem->prev = *ht_stack;
4458 		    *ht_stack = newitem;
4459 		}
4460 	    }
4461 	}
4462     }
4463     else if (tv->v_type == VAR_LIST)
4464     {
4465 	list_T	*ll = tv->vval.v_list;
4466 
4467 	if (ll != NULL && ll->lv_copyID != copyID)
4468 	{
4469 	    // Didn't see this list yet.
4470 	    ll->lv_copyID = copyID;
4471 	    if (list_stack == NULL)
4472 	    {
4473 		abort = set_ref_in_list_items(ll, copyID, ht_stack);
4474 	    }
4475 	    else
4476 	    {
4477 		list_stack_T *newitem = ALLOC_ONE(list_stack_T);
4478 
4479 		if (newitem == NULL)
4480 		    abort = TRUE;
4481 		else
4482 		{
4483 		    newitem->list = ll;
4484 		    newitem->prev = *list_stack;
4485 		    *list_stack = newitem;
4486 		}
4487 	    }
4488 	}
4489     }
4490     else if (tv->v_type == VAR_FUNC)
4491     {
4492 	abort = set_ref_in_func(tv->vval.v_string, NULL, copyID);
4493     }
4494     else if (tv->v_type == VAR_PARTIAL)
4495     {
4496 	partial_T	*pt = tv->vval.v_partial;
4497 	int		i;
4498 
4499 	if (pt != NULL && pt->pt_copyID != copyID)
4500 	{
4501 	    // Didn't see this partial yet.
4502 	    pt->pt_copyID = copyID;
4503 
4504 	    abort = set_ref_in_func(pt->pt_name, pt->pt_func, copyID);
4505 
4506 	    if (pt->pt_dict != NULL)
4507 	    {
4508 		typval_T dtv;
4509 
4510 		dtv.v_type = VAR_DICT;
4511 		dtv.vval.v_dict = pt->pt_dict;
4512 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4513 	    }
4514 
4515 	    for (i = 0; i < pt->pt_argc; ++i)
4516 		abort = abort || set_ref_in_item(&pt->pt_argv[i], copyID,
4517 							ht_stack, list_stack);
4518 	    if (pt->pt_funcstack != NULL)
4519 	    {
4520 		typval_T    *stack = pt->pt_funcstack->fs_ga.ga_data;
4521 
4522 		for (i = 0; i < pt->pt_funcstack->fs_ga.ga_len; ++i)
4523 		    abort = abort || set_ref_in_item(stack + i, copyID,
4524 							 ht_stack, list_stack);
4525 	    }
4526 
4527 	}
4528     }
4529 #ifdef FEAT_JOB_CHANNEL
4530     else if (tv->v_type == VAR_JOB)
4531     {
4532 	job_T	    *job = tv->vval.v_job;
4533 	typval_T    dtv;
4534 
4535 	if (job != NULL && job->jv_copyID != copyID)
4536 	{
4537 	    job->jv_copyID = copyID;
4538 	    if (job->jv_channel != NULL)
4539 	    {
4540 		dtv.v_type = VAR_CHANNEL;
4541 		dtv.vval.v_channel = job->jv_channel;
4542 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4543 	    }
4544 	    if (job->jv_exit_cb.cb_partial != NULL)
4545 	    {
4546 		dtv.v_type = VAR_PARTIAL;
4547 		dtv.vval.v_partial = job->jv_exit_cb.cb_partial;
4548 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4549 	    }
4550 	}
4551     }
4552     else if (tv->v_type == VAR_CHANNEL)
4553     {
4554 	channel_T   *ch =tv->vval.v_channel;
4555 	ch_part_T   part;
4556 	typval_T    dtv;
4557 	jsonq_T	    *jq;
4558 	cbq_T	    *cq;
4559 
4560 	if (ch != NULL && ch->ch_copyID != copyID)
4561 	{
4562 	    ch->ch_copyID = copyID;
4563 	    for (part = PART_SOCK; part < PART_COUNT; ++part)
4564 	    {
4565 		for (jq = ch->ch_part[part].ch_json_head.jq_next; jq != NULL;
4566 							     jq = jq->jq_next)
4567 		    set_ref_in_item(jq->jq_value, copyID, ht_stack, list_stack);
4568 		for (cq = ch->ch_part[part].ch_cb_head.cq_next; cq != NULL;
4569 							     cq = cq->cq_next)
4570 		    if (cq->cq_callback.cb_partial != NULL)
4571 		    {
4572 			dtv.v_type = VAR_PARTIAL;
4573 			dtv.vval.v_partial = cq->cq_callback.cb_partial;
4574 			set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4575 		    }
4576 		if (ch->ch_part[part].ch_callback.cb_partial != NULL)
4577 		{
4578 		    dtv.v_type = VAR_PARTIAL;
4579 		    dtv.vval.v_partial =
4580 				      ch->ch_part[part].ch_callback.cb_partial;
4581 		    set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4582 		}
4583 	    }
4584 	    if (ch->ch_callback.cb_partial != NULL)
4585 	    {
4586 		dtv.v_type = VAR_PARTIAL;
4587 		dtv.vval.v_partial = ch->ch_callback.cb_partial;
4588 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4589 	    }
4590 	    if (ch->ch_close_cb.cb_partial != NULL)
4591 	    {
4592 		dtv.v_type = VAR_PARTIAL;
4593 		dtv.vval.v_partial = ch->ch_close_cb.cb_partial;
4594 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
4595 	    }
4596 	}
4597     }
4598 #endif
4599     return abort;
4600 }
4601 
4602 /*
4603  * Return a string with the string representation of a variable.
4604  * If the memory is allocated "tofree" is set to it, otherwise NULL.
4605  * "numbuf" is used for a number.
4606  * When "copyID" is not NULL replace recursive lists and dicts with "...".
4607  * When both "echo_style" and "composite_val" are FALSE, put quotes around
4608  * stings as "string()", otherwise does not put quotes around strings, as
4609  * ":echo" displays values.
4610  * When "restore_copyID" is FALSE, repeated items in dictionaries and lists
4611  * are replaced with "...".
4612  * May return NULL.
4613  */
4614     char_u *
4615 echo_string_core(
4616     typval_T	*tv,
4617     char_u	**tofree,
4618     char_u	*numbuf,
4619     int		copyID,
4620     int		echo_style,
4621     int		restore_copyID,
4622     int		composite_val)
4623 {
4624     static int	recurse = 0;
4625     char_u	*r = NULL;
4626 
4627     if (recurse >= DICT_MAXNEST)
4628     {
4629 	if (!did_echo_string_emsg)
4630 	{
4631 	    // Only give this message once for a recursive call to avoid
4632 	    // flooding the user with errors.  And stop iterating over lists
4633 	    // and dicts.
4634 	    did_echo_string_emsg = TRUE;
4635 	    emsg(_("E724: variable nested too deep for displaying"));
4636 	}
4637 	*tofree = NULL;
4638 	return (char_u *)"{E724}";
4639     }
4640     ++recurse;
4641 
4642     switch (tv->v_type)
4643     {
4644 	case VAR_STRING:
4645 	    if (echo_style && !composite_val)
4646 	    {
4647 		*tofree = NULL;
4648 		r = tv->vval.v_string;
4649 		if (r == NULL)
4650 		    r = (char_u *)"";
4651 	    }
4652 	    else
4653 	    {
4654 		*tofree = string_quote(tv->vval.v_string, FALSE);
4655 		r = *tofree;
4656 	    }
4657 	    break;
4658 
4659 	case VAR_FUNC:
4660 	    if (echo_style)
4661 	    {
4662 		*tofree = NULL;
4663 		r = tv->vval.v_string;
4664 	    }
4665 	    else
4666 	    {
4667 		*tofree = string_quote(tv->vval.v_string, TRUE);
4668 		r = *tofree;
4669 	    }
4670 	    break;
4671 
4672 	case VAR_PARTIAL:
4673 	    {
4674 		partial_T   *pt = tv->vval.v_partial;
4675 		char_u	    *fname = string_quote(pt == NULL ? NULL
4676 						    : partial_name(pt), FALSE);
4677 		garray_T    ga;
4678 		int	    i;
4679 		char_u	    *tf;
4680 
4681 		ga_init2(&ga, 1, 100);
4682 		ga_concat(&ga, (char_u *)"function(");
4683 		if (fname != NULL)
4684 		{
4685 		    ga_concat(&ga, fname);
4686 		    vim_free(fname);
4687 		}
4688 		if (pt != NULL && pt->pt_argc > 0)
4689 		{
4690 		    ga_concat(&ga, (char_u *)", [");
4691 		    for (i = 0; i < pt->pt_argc; ++i)
4692 		    {
4693 			if (i > 0)
4694 			    ga_concat(&ga, (char_u *)", ");
4695 			ga_concat(&ga,
4696 			     tv2string(&pt->pt_argv[i], &tf, numbuf, copyID));
4697 			vim_free(tf);
4698 		    }
4699 		    ga_concat(&ga, (char_u *)"]");
4700 		}
4701 		if (pt != NULL && pt->pt_dict != NULL)
4702 		{
4703 		    typval_T dtv;
4704 
4705 		    ga_concat(&ga, (char_u *)", ");
4706 		    dtv.v_type = VAR_DICT;
4707 		    dtv.vval.v_dict = pt->pt_dict;
4708 		    ga_concat(&ga, tv2string(&dtv, &tf, numbuf, copyID));
4709 		    vim_free(tf);
4710 		}
4711 		ga_concat(&ga, (char_u *)")");
4712 
4713 		*tofree = ga.ga_data;
4714 		r = *tofree;
4715 		break;
4716 	    }
4717 
4718 	case VAR_BLOB:
4719 	    r = blob2string(tv->vval.v_blob, tofree, numbuf);
4720 	    break;
4721 
4722 	case VAR_LIST:
4723 	    if (tv->vval.v_list == NULL)
4724 	    {
4725 		// NULL list is equivalent to empty list.
4726 		*tofree = NULL;
4727 		r = (char_u *)"[]";
4728 	    }
4729 	    else if (copyID != 0 && tv->vval.v_list->lv_copyID == copyID
4730 		    && tv->vval.v_list->lv_len > 0)
4731 	    {
4732 		*tofree = NULL;
4733 		r = (char_u *)"[...]";
4734 	    }
4735 	    else
4736 	    {
4737 		int old_copyID = tv->vval.v_list->lv_copyID;
4738 
4739 		tv->vval.v_list->lv_copyID = copyID;
4740 		*tofree = list2string(tv, copyID, restore_copyID);
4741 		if (restore_copyID)
4742 		    tv->vval.v_list->lv_copyID = old_copyID;
4743 		r = *tofree;
4744 	    }
4745 	    break;
4746 
4747 	case VAR_DICT:
4748 	    if (tv->vval.v_dict == NULL)
4749 	    {
4750 		// NULL dict is equivalent to empty dict.
4751 		*tofree = NULL;
4752 		r = (char_u *)"{}";
4753 	    }
4754 	    else if (copyID != 0 && tv->vval.v_dict->dv_copyID == copyID
4755 		    && tv->vval.v_dict->dv_hashtab.ht_used != 0)
4756 	    {
4757 		*tofree = NULL;
4758 		r = (char_u *)"{...}";
4759 	    }
4760 	    else
4761 	    {
4762 		int old_copyID = tv->vval.v_dict->dv_copyID;
4763 
4764 		tv->vval.v_dict->dv_copyID = copyID;
4765 		*tofree = dict2string(tv, copyID, restore_copyID);
4766 		if (restore_copyID)
4767 		    tv->vval.v_dict->dv_copyID = old_copyID;
4768 		r = *tofree;
4769 	    }
4770 	    break;
4771 
4772 	case VAR_NUMBER:
4773 	case VAR_UNKNOWN:
4774 	case VAR_ANY:
4775 	case VAR_VOID:
4776 	    *tofree = NULL;
4777 	    r = tv_get_string_buf(tv, numbuf);
4778 	    break;
4779 
4780 	case VAR_JOB:
4781 	case VAR_CHANNEL:
4782 	    *tofree = NULL;
4783 	    r = tv_get_string_buf(tv, numbuf);
4784 	    if (composite_val)
4785 	    {
4786 		*tofree = string_quote(r, FALSE);
4787 		r = *tofree;
4788 	    }
4789 	    break;
4790 
4791 	case VAR_FLOAT:
4792 #ifdef FEAT_FLOAT
4793 	    *tofree = NULL;
4794 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv->vval.v_float);
4795 	    r = numbuf;
4796 	    break;
4797 #endif
4798 
4799 	case VAR_BOOL:
4800 	case VAR_SPECIAL:
4801 	    *tofree = NULL;
4802 	    r = (char_u *)get_var_special_name(tv->vval.v_number);
4803 	    break;
4804     }
4805 
4806     if (--recurse == 0)
4807 	did_echo_string_emsg = FALSE;
4808     return r;
4809 }
4810 
4811 /*
4812  * Return a string with the string representation of a variable.
4813  * If the memory is allocated "tofree" is set to it, otherwise NULL.
4814  * "numbuf" is used for a number.
4815  * Does not put quotes around strings, as ":echo" displays values.
4816  * When "copyID" is not NULL replace recursive lists and dicts with "...".
4817  * May return NULL.
4818  */
4819     char_u *
4820 echo_string(
4821     typval_T	*tv,
4822     char_u	**tofree,
4823     char_u	*numbuf,
4824     int		copyID)
4825 {
4826     return echo_string_core(tv, tofree, numbuf, copyID, TRUE, FALSE, FALSE);
4827 }
4828 
4829 /*
4830  * Return string "str" in ' quotes, doubling ' characters.
4831  * If "str" is NULL an empty string is assumed.
4832  * If "function" is TRUE make it function('string').
4833  */
4834     char_u *
4835 string_quote(char_u *str, int function)
4836 {
4837     unsigned	len;
4838     char_u	*p, *r, *s;
4839 
4840     len = (function ? 13 : 3);
4841     if (str != NULL)
4842     {
4843 	len += (unsigned)STRLEN(str);
4844 	for (p = str; *p != NUL; MB_PTR_ADV(p))
4845 	    if (*p == '\'')
4846 		++len;
4847     }
4848     s = r = alloc(len);
4849     if (r != NULL)
4850     {
4851 	if (function)
4852 	{
4853 	    STRCPY(r, "function('");
4854 	    r += 10;
4855 	}
4856 	else
4857 	    *r++ = '\'';
4858 	if (str != NULL)
4859 	    for (p = str; *p != NUL; )
4860 	    {
4861 		if (*p == '\'')
4862 		    *r++ = '\'';
4863 		MB_COPY_CHAR(p, r);
4864 	    }
4865 	*r++ = '\'';
4866 	if (function)
4867 	    *r++ = ')';
4868 	*r++ = NUL;
4869     }
4870     return s;
4871 }
4872 
4873 #if defined(FEAT_FLOAT) || defined(PROTO)
4874 /*
4875  * Convert the string "text" to a floating point number.
4876  * This uses strtod().  setlocale(LC_NUMERIC, "C") has been used to make sure
4877  * this always uses a decimal point.
4878  * Returns the length of the text that was consumed.
4879  */
4880     int
4881 string2float(
4882     char_u	*text,
4883     float_T	*value)	    // result stored here
4884 {
4885     char	*s = (char *)text;
4886     float_T	f;
4887 
4888     // MS-Windows does not deal with "inf" and "nan" properly.
4889     if (STRNICMP(text, "inf", 3) == 0)
4890     {
4891 	*value = INFINITY;
4892 	return 3;
4893     }
4894     if (STRNICMP(text, "-inf", 3) == 0)
4895     {
4896 	*value = -INFINITY;
4897 	return 4;
4898     }
4899     if (STRNICMP(text, "nan", 3) == 0)
4900     {
4901 	*value = NAN;
4902 	return 3;
4903     }
4904     f = strtod(s, &s);
4905     *value = f;
4906     return (int)((char_u *)s - text);
4907 }
4908 #endif
4909 
4910 /*
4911  * Translate a String variable into a position.
4912  * Returns NULL when there is an error.
4913  */
4914     pos_T *
4915 var2fpos(
4916     typval_T	*varp,
4917     int		dollar_lnum,	// TRUE when $ is last line
4918     int		*fnum)		// set to fnum for '0, 'A, etc.
4919 {
4920     char_u		*name;
4921     static pos_T	pos;
4922     pos_T		*pp;
4923 
4924     // Argument can be [lnum, col, coladd].
4925     if (varp->v_type == VAR_LIST)
4926     {
4927 	list_T		*l;
4928 	int		len;
4929 	int		error = FALSE;
4930 	listitem_T	*li;
4931 
4932 	l = varp->vval.v_list;
4933 	if (l == NULL)
4934 	    return NULL;
4935 
4936 	// Get the line number
4937 	pos.lnum = list_find_nr(l, 0L, &error);
4938 	if (error || pos.lnum <= 0 || pos.lnum > curbuf->b_ml.ml_line_count)
4939 	    return NULL;	// invalid line number
4940 	len = (long)STRLEN(ml_get(pos.lnum));
4941 
4942 	// Get the column number
4943 	// We accept "$" for the column number: last column.
4944 	li = list_find(l, 1L);
4945 	if (li != NULL && li->li_tv.v_type == VAR_STRING
4946 		&& li->li_tv.vval.v_string != NULL
4947 		&& STRCMP(li->li_tv.vval.v_string, "$") == 0)
4948 	{
4949 	    pos.col = len + 1;
4950 	}
4951 	else
4952 	{
4953 	    pos.col = list_find_nr(l, 1L, &error);
4954 	    if (error)
4955 		return NULL;
4956 	}
4957 
4958 	// Accept a position up to the NUL after the line.
4959 	if (pos.col == 0 || (int)pos.col > len + 1)
4960 	    return NULL;	// invalid column number
4961 	--pos.col;
4962 
4963 	// Get the virtual offset.  Defaults to zero.
4964 	pos.coladd = list_find_nr(l, 2L, &error);
4965 	if (error)
4966 	    pos.coladd = 0;
4967 
4968 	return &pos;
4969     }
4970 
4971     name = tv_get_string_chk(varp);
4972     if (name == NULL)
4973 	return NULL;
4974     if (name[0] == '.')				// cursor
4975 	return &curwin->w_cursor;
4976     if (name[0] == 'v' && name[1] == NUL)	// Visual start
4977     {
4978 	if (VIsual_active)
4979 	    return &VIsual;
4980 	return &curwin->w_cursor;
4981     }
4982     if (name[0] == '\'')			// mark
4983     {
4984 	pp = getmark_buf_fnum(curbuf, name[1], FALSE, fnum);
4985 	if (pp == NULL || pp == (pos_T *)-1 || pp->lnum <= 0)
4986 	    return NULL;
4987 	return pp;
4988     }
4989 
4990     pos.coladd = 0;
4991 
4992     if (name[0] == 'w' && dollar_lnum)
4993     {
4994 	pos.col = 0;
4995 	if (name[1] == '0')		// "w0": first visible line
4996 	{
4997 	    update_topline();
4998 	    // In silent Ex mode topline is zero, but that's not a valid line
4999 	    // number; use one instead.
5000 	    pos.lnum = curwin->w_topline > 0 ? curwin->w_topline : 1;
5001 	    return &pos;
5002 	}
5003 	else if (name[1] == '$')	// "w$": last visible line
5004 	{
5005 	    validate_botline();
5006 	    // In silent Ex mode botline is zero, return zero then.
5007 	    pos.lnum = curwin->w_botline > 0 ? curwin->w_botline - 1 : 0;
5008 	    return &pos;
5009 	}
5010     }
5011     else if (name[0] == '$')		// last column or line
5012     {
5013 	if (dollar_lnum)
5014 	{
5015 	    pos.lnum = curbuf->b_ml.ml_line_count;
5016 	    pos.col = 0;
5017 	}
5018 	else
5019 	{
5020 	    pos.lnum = curwin->w_cursor.lnum;
5021 	    pos.col = (colnr_T)STRLEN(ml_get_curline());
5022 	}
5023 	return &pos;
5024     }
5025     return NULL;
5026 }
5027 
5028 /*
5029  * Convert list in "arg" into a position and optional file number.
5030  * When "fnump" is NULL there is no file number, only 3 items.
5031  * Note that the column is passed on as-is, the caller may want to decrement
5032  * it to use 1 for the first column.
5033  * Return FAIL when conversion is not possible, doesn't check the position for
5034  * validity.
5035  */
5036     int
5037 list2fpos(
5038     typval_T	*arg,
5039     pos_T	*posp,
5040     int		*fnump,
5041     colnr_T	*curswantp)
5042 {
5043     list_T	*l = arg->vval.v_list;
5044     long	i = 0;
5045     long	n;
5046 
5047     // List must be: [fnum, lnum, col, coladd, curswant], where "fnum" is only
5048     // there when "fnump" isn't NULL; "coladd" and "curswant" are optional.
5049     if (arg->v_type != VAR_LIST
5050 	    || l == NULL
5051 	    || l->lv_len < (fnump == NULL ? 2 : 3)
5052 	    || l->lv_len > (fnump == NULL ? 4 : 5))
5053 	return FAIL;
5054 
5055     if (fnump != NULL)
5056     {
5057 	n = list_find_nr(l, i++, NULL);	// fnum
5058 	if (n < 0)
5059 	    return FAIL;
5060 	if (n == 0)
5061 	    n = curbuf->b_fnum;		// current buffer
5062 	*fnump = n;
5063     }
5064 
5065     n = list_find_nr(l, i++, NULL);	// lnum
5066     if (n < 0)
5067 	return FAIL;
5068     posp->lnum = n;
5069 
5070     n = list_find_nr(l, i++, NULL);	// col
5071     if (n < 0)
5072 	return FAIL;
5073     posp->col = n;
5074 
5075     n = list_find_nr(l, i, NULL);	// off
5076     if (n < 0)
5077 	posp->coladd = 0;
5078     else
5079 	posp->coladd = n;
5080 
5081     if (curswantp != NULL)
5082 	*curswantp = list_find_nr(l, i + 1, NULL);  // curswant
5083 
5084     return OK;
5085 }
5086 
5087 /*
5088  * Get the length of an environment variable name.
5089  * Advance "arg" to the first character after the name.
5090  * Return 0 for error.
5091  */
5092     int
5093 get_env_len(char_u **arg)
5094 {
5095     char_u	*p;
5096     int		len;
5097 
5098     for (p = *arg; vim_isIDc(*p); ++p)
5099 	;
5100     if (p == *arg)	    // no name found
5101 	return 0;
5102 
5103     len = (int)(p - *arg);
5104     *arg = p;
5105     return len;
5106 }
5107 
5108 /*
5109  * Get the length of the name of a function or internal variable.
5110  * "arg" is advanced to after the name.
5111  * Return 0 if something is wrong.
5112  */
5113     int
5114 get_id_len(char_u **arg)
5115 {
5116     char_u	*p;
5117     int		len;
5118 
5119     // Find the end of the name.
5120     for (p = *arg; eval_isnamec(*p); ++p)
5121     {
5122 	if (*p == ':')
5123 	{
5124 	    // "s:" is start of "s:var", but "n:" is not and can be used in
5125 	    // slice "[n:]".  Also "xx:" is not a namespace.
5126 	    len = (int)(p - *arg);
5127 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, **arg) == NULL)
5128 		    || len > 1)
5129 		break;
5130 	}
5131     }
5132     if (p == *arg)	    // no name found
5133 	return 0;
5134 
5135     len = (int)(p - *arg);
5136     *arg = p;
5137 
5138     return len;
5139 }
5140 
5141 /*
5142  * Get the length of the name of a variable or function.
5143  * Only the name is recognized, does not handle ".key" or "[idx]".
5144  * "arg" is advanced to the first non-white character after the name.
5145  * Return -1 if curly braces expansion failed.
5146  * Return 0 if something else is wrong.
5147  * If the name contains 'magic' {}'s, expand them and return the
5148  * expanded name in an allocated string via 'alias' - caller must free.
5149  */
5150     int
5151 get_name_len(
5152     char_u	**arg,
5153     char_u	**alias,
5154     int		evaluate,
5155     int		verbose)
5156 {
5157     int		len;
5158     char_u	*p;
5159     char_u	*expr_start;
5160     char_u	*expr_end;
5161 
5162     *alias = NULL;  // default to no alias
5163 
5164     if ((*arg)[0] == K_SPECIAL && (*arg)[1] == KS_EXTRA
5165 						  && (*arg)[2] == (int)KE_SNR)
5166     {
5167 	// hard coded <SNR>, already translated
5168 	*arg += 3;
5169 	return get_id_len(arg) + 3;
5170     }
5171     len = eval_fname_script(*arg);
5172     if (len > 0)
5173     {
5174 	// literal "<SID>", "s:" or "<SNR>"
5175 	*arg += len;
5176     }
5177 
5178     /*
5179      * Find the end of the name; check for {} construction.
5180      */
5181     p = find_name_end(*arg, &expr_start, &expr_end,
5182 					       len > 0 ? 0 : FNE_CHECK_START);
5183     if (expr_start != NULL)
5184     {
5185 	char_u	*temp_string;
5186 
5187 	if (!evaluate)
5188 	{
5189 	    len += (int)(p - *arg);
5190 	    *arg = skipwhite(p);
5191 	    return len;
5192 	}
5193 
5194 	/*
5195 	 * Include any <SID> etc in the expanded string:
5196 	 * Thus the -len here.
5197 	 */
5198 	temp_string = make_expanded_name(*arg - len, expr_start, expr_end, p);
5199 	if (temp_string == NULL)
5200 	    return -1;
5201 	*alias = temp_string;
5202 	*arg = skipwhite(p);
5203 	return (int)STRLEN(temp_string);
5204     }
5205 
5206     len += get_id_len(arg);
5207     // Only give an error when there is something, otherwise it will be
5208     // reported at a higher level.
5209     if (len == 0 && verbose && **arg != NUL)
5210 	semsg(_(e_invexpr2), *arg);
5211 
5212     return len;
5213 }
5214 
5215 /*
5216  * Find the end of a variable or function name, taking care of magic braces.
5217  * If "expr_start" is not NULL then "expr_start" and "expr_end" are set to the
5218  * start and end of the first magic braces item.
5219  * "flags" can have FNE_INCL_BR and FNE_CHECK_START.
5220  * Return a pointer to just after the name.  Equal to "arg" if there is no
5221  * valid name.
5222  */
5223     char_u *
5224 find_name_end(
5225     char_u	*arg,
5226     char_u	**expr_start,
5227     char_u	**expr_end,
5228     int		flags)
5229 {
5230     int		mb_nest = 0;
5231     int		br_nest = 0;
5232     char_u	*p;
5233     int		len;
5234     int		vim9script = in_vim9script();
5235 
5236     if (expr_start != NULL)
5237     {
5238 	*expr_start = NULL;
5239 	*expr_end = NULL;
5240     }
5241 
5242     // Quick check for valid starting character.
5243     if ((flags & FNE_CHECK_START) && !eval_isnamec1(*arg)
5244 						&& (*arg != '{' || vim9script))
5245 	return arg;
5246 
5247     for (p = arg; *p != NUL
5248 		    && (eval_isnamec(*p)
5249 			|| (*p == '{' && !vim9script)
5250 			|| ((flags & FNE_INCL_BR) && (*p == '['
5251 					 || (*p == '.' && eval_isdictc(p[1]))))
5252 			|| mb_nest != 0
5253 			|| br_nest != 0); MB_PTR_ADV(p))
5254     {
5255 	if (*p == '\'')
5256 	{
5257 	    // skip over 'string' to avoid counting [ and ] inside it.
5258 	    for (p = p + 1; *p != NUL && *p != '\''; MB_PTR_ADV(p))
5259 		;
5260 	    if (*p == NUL)
5261 		break;
5262 	}
5263 	else if (*p == '"')
5264 	{
5265 	    // skip over "str\"ing" to avoid counting [ and ] inside it.
5266 	    for (p = p + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
5267 		if (*p == '\\' && p[1] != NUL)
5268 		    ++p;
5269 	    if (*p == NUL)
5270 		break;
5271 	}
5272 	else if (br_nest == 0 && mb_nest == 0 && *p == ':')
5273 	{
5274 	    // "s:" is start of "s:var", but "n:" is not and can be used in
5275 	    // slice "[n:]".  Also "xx:" is not a namespace. But {ns}: is.
5276 	    len = (int)(p - arg);
5277 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, *arg) == NULL)
5278 		    || (len > 1 && p[-1] != '}'))
5279 		break;
5280 	}
5281 
5282 	if (mb_nest == 0)
5283 	{
5284 	    if (*p == '[')
5285 		++br_nest;
5286 	    else if (*p == ']')
5287 		--br_nest;
5288 	}
5289 
5290 	if (br_nest == 0 && !vim9script)
5291 	{
5292 	    if (*p == '{')
5293 	    {
5294 		mb_nest++;
5295 		if (expr_start != NULL && *expr_start == NULL)
5296 		    *expr_start = p;
5297 	    }
5298 	    else if (*p == '}')
5299 	    {
5300 		mb_nest--;
5301 		if (expr_start != NULL && mb_nest == 0 && *expr_end == NULL)
5302 		    *expr_end = p;
5303 	    }
5304 	}
5305     }
5306 
5307     return p;
5308 }
5309 
5310 /*
5311  * Expands out the 'magic' {}'s in a variable/function name.
5312  * Note that this can call itself recursively, to deal with
5313  * constructs like foo{bar}{baz}{bam}
5314  * The four pointer arguments point to "foo{expre}ss{ion}bar"
5315  *			"in_start"      ^
5316  *			"expr_start"	   ^
5317  *			"expr_end"		 ^
5318  *			"in_end"			    ^
5319  *
5320  * Returns a new allocated string, which the caller must free.
5321  * Returns NULL for failure.
5322  */
5323     static char_u *
5324 make_expanded_name(
5325     char_u	*in_start,
5326     char_u	*expr_start,
5327     char_u	*expr_end,
5328     char_u	*in_end)
5329 {
5330     char_u	c1;
5331     char_u	*retval = NULL;
5332     char_u	*temp_result;
5333 
5334     if (expr_end == NULL || in_end == NULL)
5335 	return NULL;
5336     *expr_start	= NUL;
5337     *expr_end = NUL;
5338     c1 = *in_end;
5339     *in_end = NUL;
5340 
5341     temp_result = eval_to_string(expr_start + 1, FALSE);
5342     if (temp_result != NULL)
5343     {
5344 	retval = alloc(STRLEN(temp_result) + (expr_start - in_start)
5345 						   + (in_end - expr_end) + 1);
5346 	if (retval != NULL)
5347 	{
5348 	    STRCPY(retval, in_start);
5349 	    STRCAT(retval, temp_result);
5350 	    STRCAT(retval, expr_end + 1);
5351 	}
5352     }
5353     vim_free(temp_result);
5354 
5355     *in_end = c1;		// put char back for error messages
5356     *expr_start = '{';
5357     *expr_end = '}';
5358 
5359     if (retval != NULL)
5360     {
5361 	temp_result = find_name_end(retval, &expr_start, &expr_end, 0);
5362 	if (expr_start != NULL)
5363 	{
5364 	    // Further expansion!
5365 	    temp_result = make_expanded_name(retval, expr_start,
5366 						       expr_end, temp_result);
5367 	    vim_free(retval);
5368 	    retval = temp_result;
5369 	}
5370     }
5371 
5372     return retval;
5373 }
5374 
5375 /*
5376  * Return TRUE if character "c" can be used in a variable or function name.
5377  * Does not include '{' or '}' for magic braces.
5378  */
5379     int
5380 eval_isnamec(int c)
5381 {
5382     return ASCII_ISALNUM(c) || c == '_' || c == ':' || c == AUTOLOAD_CHAR;
5383 }
5384 
5385 /*
5386  * Return TRUE if character "c" can be used as the first character in a
5387  * variable or function name (excluding '{' and '}').
5388  */
5389     int
5390 eval_isnamec1(int c)
5391 {
5392     return ASCII_ISALPHA(c) || c == '_';
5393 }
5394 
5395 /*
5396  * Return TRUE if character "c" can be used as the first character of a
5397  * dictionary key.
5398  */
5399     int
5400 eval_isdictc(int c)
5401 {
5402     return ASCII_ISALNUM(c) || c == '_';
5403 }
5404 
5405 /*
5406  * Return the character "str[index]" where "index" is the character index.  If
5407  * "index" is out of range NULL is returned.
5408  */
5409     char_u *
5410 char_from_string(char_u *str, varnumber_T index)
5411 {
5412     size_t	    nbyte = 0;
5413     varnumber_T	    nchar = index;
5414     size_t	    slen;
5415 
5416     if (str == NULL || index < 0)
5417 	return NULL;
5418     slen = STRLEN(str);
5419     while (nchar > 0 && nbyte < slen)
5420     {
5421 	nbyte += MB_CPTR2LEN(str + nbyte);
5422 	--nchar;
5423     }
5424     if (nbyte >= slen)
5425 	return NULL;
5426     return vim_strnsave(str + nbyte, MB_CPTR2LEN(str + nbyte));
5427 }
5428 
5429 /*
5430  * Get the byte index for character index "idx" in string "str" with length
5431  * "str_len".
5432  * If going over the end return "str_len".
5433  * If "idx" is negative count from the end, -1 is the last character.
5434  * When going over the start return -1.
5435  */
5436     static long
5437 char_idx2byte(char_u *str, size_t str_len, varnumber_T idx)
5438 {
5439     varnumber_T nchar = idx;
5440     size_t	nbyte = 0;
5441 
5442     if (nchar >= 0)
5443     {
5444 	while (nchar > 0 && nbyte < str_len)
5445 	{
5446 	    nbyte += MB_CPTR2LEN(str + nbyte);
5447 	    --nchar;
5448 	}
5449     }
5450     else
5451     {
5452 	nbyte = str_len;
5453 	while (nchar < 0 && nbyte > 0)
5454 	{
5455 	    --nbyte;
5456 	    nbyte -= mb_head_off(str, str + nbyte);
5457 	    ++nchar;
5458 	}
5459 	if (nchar < 0)
5460 	    return -1;
5461     }
5462     return (long)nbyte;
5463 }
5464 
5465 /*
5466  * Return the slice "str[first:last]" using character indexes.
5467  * Return NULL when the result is empty.
5468  */
5469     char_u *
5470 string_slice(char_u *str, varnumber_T first, varnumber_T last)
5471 {
5472     long	start_byte, end_byte;
5473     size_t	slen;
5474 
5475     if (str == NULL)
5476 	return NULL;
5477     slen = STRLEN(str);
5478     start_byte = char_idx2byte(str, slen, first);
5479     if (start_byte < 0)
5480 	start_byte = 0; // first index very negative: use zero
5481     if (last == -1)
5482 	end_byte = (long)slen;
5483     else
5484     {
5485 	end_byte = char_idx2byte(str, slen, last);
5486 	if (end_byte >= 0 && end_byte < (long)slen)
5487 	    // end index is inclusive
5488 	    end_byte += MB_CPTR2LEN(str + end_byte);
5489     }
5490 
5491     if (start_byte >= (long)slen || end_byte <= start_byte)
5492 	return NULL;
5493     return vim_strnsave(str + start_byte, end_byte - start_byte);
5494 }
5495 
5496 /*
5497  * Handle:
5498  * - expr[expr], expr[expr:expr] subscript
5499  * - ".name" lookup
5500  * - function call with Funcref variable: func(expr)
5501  * - method call: var->method()
5502  *
5503  * Can all be combined in any order: dict.func(expr)[idx]['func'](expr)->len()
5504  */
5505     int
5506 handle_subscript(
5507     char_u	**arg,
5508     typval_T	*rettv,
5509     evalarg_T	*evalarg,
5510     int		verbose)	// give error messages
5511 {
5512     int		evaluate = evalarg != NULL
5513 				      && (evalarg->eval_flags & EVAL_EVALUATE);
5514     int		ret = OK;
5515     dict_T	*selfdict = NULL;
5516     int		check_white = TRUE;
5517     int		getnext;
5518     char_u	*p;
5519 
5520     while (ret == OK)
5521     {
5522 	// When at the end of the line and ".name" or "->{" or "->X" follows in
5523 	// the next line then consume the line break.
5524 	p = eval_next_non_blank(*arg, evalarg, &getnext);
5525 	if (getnext
5526 	    && ((rettv->v_type == VAR_DICT && *p == '.' && eval_isdictc(p[1]))
5527 		|| (p[0] == '-' && p[1] == '>'
5528 				     && (p[2] == '{' || ASCII_ISALPHA(p[2])))))
5529 	{
5530 	    *arg = eval_next_line(evalarg);
5531 	    p = *arg;
5532 	    check_white = FALSE;
5533 	}
5534 
5535 	if ((**arg == '(' && (!evaluate || rettv->v_type == VAR_FUNC
5536 			    || rettv->v_type == VAR_PARTIAL))
5537 		    && (!check_white || !VIM_ISWHITE(*(*arg - 1))))
5538 	{
5539 	    ret = call_func_rettv(arg, evalarg, rettv, evaluate,
5540 							       selfdict, NULL);
5541 
5542 	    // Stop the expression evaluation when immediately aborting on
5543 	    // error, or when an interrupt occurred or an exception was thrown
5544 	    // but not caught.
5545 	    if (aborting())
5546 	    {
5547 		if (ret == OK)
5548 		    clear_tv(rettv);
5549 		ret = FAIL;
5550 	    }
5551 	    dict_unref(selfdict);
5552 	    selfdict = NULL;
5553 	}
5554 	else if (p[0] == '-' && p[1] == '>')
5555 	{
5556 	    *arg = p;
5557 	    if (ret == OK)
5558 	    {
5559 		if ((*arg)[2] == '{')
5560 		    // expr->{lambda}()
5561 		    ret = eval_lambda(arg, rettv, evalarg, verbose);
5562 		else
5563 		    // expr->name()
5564 		    ret = eval_method(arg, rettv, evalarg, verbose);
5565 	    }
5566 	}
5567 	// "." is ".name" lookup when we found a dict or when evaluating and
5568 	// scriptversion is at least 2, where string concatenation is "..".
5569 	else if (**arg == '['
5570 		|| (**arg == '.' && (rettv->v_type == VAR_DICT
5571 			|| (!evaluate
5572 			    && (*arg)[1] != '.'
5573 			    && current_sctx.sc_version >= 2))))
5574 	{
5575 	    dict_unref(selfdict);
5576 	    if (rettv->v_type == VAR_DICT)
5577 	    {
5578 		selfdict = rettv->vval.v_dict;
5579 		if (selfdict != NULL)
5580 		    ++selfdict->dv_refcount;
5581 	    }
5582 	    else
5583 		selfdict = NULL;
5584 	    if (eval_index(arg, rettv, evalarg, verbose) == FAIL)
5585 	    {
5586 		clear_tv(rettv);
5587 		ret = FAIL;
5588 	    }
5589 	}
5590 	else
5591 	    break;
5592     }
5593 
5594     // Turn "dict.Func" into a partial for "Func" bound to "dict".
5595     // Don't do this when "Func" is already a partial that was bound
5596     // explicitly (pt_auto is FALSE).
5597     if (selfdict != NULL
5598 	    && (rettv->v_type == VAR_FUNC
5599 		|| (rettv->v_type == VAR_PARTIAL
5600 		    && (rettv->vval.v_partial->pt_auto
5601 			|| rettv->vval.v_partial->pt_dict == NULL))))
5602 	selfdict = make_partial(selfdict, rettv);
5603 
5604     dict_unref(selfdict);
5605     return ret;
5606 }
5607 
5608 /*
5609  * Make a copy of an item.
5610  * Lists and Dictionaries are also copied.  A deep copy if "deep" is set.
5611  * For deepcopy() "copyID" is zero for a full copy or the ID for when a
5612  * reference to an already copied list/dict can be used.
5613  * Returns FAIL or OK.
5614  */
5615     int
5616 item_copy(
5617     typval_T	*from,
5618     typval_T	*to,
5619     int		deep,
5620     int		copyID)
5621 {
5622     static int	recurse = 0;
5623     int		ret = OK;
5624 
5625     if (recurse >= DICT_MAXNEST)
5626     {
5627 	emsg(_("E698: variable nested too deep for making a copy"));
5628 	return FAIL;
5629     }
5630     ++recurse;
5631 
5632     switch (from->v_type)
5633     {
5634 	case VAR_NUMBER:
5635 	case VAR_FLOAT:
5636 	case VAR_STRING:
5637 	case VAR_FUNC:
5638 	case VAR_PARTIAL:
5639 	case VAR_BOOL:
5640 	case VAR_SPECIAL:
5641 	case VAR_JOB:
5642 	case VAR_CHANNEL:
5643 	    copy_tv(from, to);
5644 	    break;
5645 	case VAR_LIST:
5646 	    to->v_type = VAR_LIST;
5647 	    to->v_lock = 0;
5648 	    if (from->vval.v_list == NULL)
5649 		to->vval.v_list = NULL;
5650 	    else if (copyID != 0 && from->vval.v_list->lv_copyID == copyID)
5651 	    {
5652 		// use the copy made earlier
5653 		to->vval.v_list = from->vval.v_list->lv_copylist;
5654 		++to->vval.v_list->lv_refcount;
5655 	    }
5656 	    else
5657 		to->vval.v_list = list_copy(from->vval.v_list, deep, copyID);
5658 	    if (to->vval.v_list == NULL)
5659 		ret = FAIL;
5660 	    break;
5661 	case VAR_BLOB:
5662 	    ret = blob_copy(from->vval.v_blob, to);
5663 	    break;
5664 	case VAR_DICT:
5665 	    to->v_type = VAR_DICT;
5666 	    to->v_lock = 0;
5667 	    if (from->vval.v_dict == NULL)
5668 		to->vval.v_dict = NULL;
5669 	    else if (copyID != 0 && from->vval.v_dict->dv_copyID == copyID)
5670 	    {
5671 		// use the copy made earlier
5672 		to->vval.v_dict = from->vval.v_dict->dv_copydict;
5673 		++to->vval.v_dict->dv_refcount;
5674 	    }
5675 	    else
5676 		to->vval.v_dict = dict_copy(from->vval.v_dict, deep, copyID);
5677 	    if (to->vval.v_dict == NULL)
5678 		ret = FAIL;
5679 	    break;
5680 	case VAR_UNKNOWN:
5681 	case VAR_ANY:
5682 	case VAR_VOID:
5683 	    internal_error_no_abort("item_copy(UNKNOWN)");
5684 	    ret = FAIL;
5685     }
5686     --recurse;
5687     return ret;
5688 }
5689 
5690     void
5691 echo_one(typval_T *rettv, int with_space, int *atstart, int *needclr)
5692 {
5693     char_u	*tofree;
5694     char_u	numbuf[NUMBUFLEN];
5695     char_u	*p = echo_string(rettv, &tofree, numbuf, get_copyID());
5696 
5697     if (*atstart)
5698     {
5699 	*atstart = FALSE;
5700 	// Call msg_start() after eval1(), evaluating the expression
5701 	// may cause a message to appear.
5702 	if (with_space)
5703 	{
5704 	    // Mark the saved text as finishing the line, so that what
5705 	    // follows is displayed on a new line when scrolling back
5706 	    // at the more prompt.
5707 	    msg_sb_eol();
5708 	    msg_start();
5709 	}
5710     }
5711     else if (with_space)
5712 	msg_puts_attr(" ", echo_attr);
5713 
5714     if (p != NULL)
5715 	for ( ; *p != NUL && !got_int; ++p)
5716 	{
5717 	    if (*p == '\n' || *p == '\r' || *p == TAB)
5718 	    {
5719 		if (*p != TAB && *needclr)
5720 		{
5721 		    // remove any text still there from the command
5722 		    msg_clr_eos();
5723 		    *needclr = FALSE;
5724 		}
5725 		msg_putchar_attr(*p, echo_attr);
5726 	    }
5727 	    else
5728 	    {
5729 		if (has_mbyte)
5730 		{
5731 		    int i = (*mb_ptr2len)(p);
5732 
5733 		    (void)msg_outtrans_len_attr(p, i, echo_attr);
5734 		    p += i - 1;
5735 		}
5736 		else
5737 		    (void)msg_outtrans_len_attr(p, 1, echo_attr);
5738 	    }
5739 	}
5740     vim_free(tofree);
5741 }
5742 
5743 /*
5744  * ":echo expr1 ..."	print each argument separated with a space, add a
5745  *			newline at the end.
5746  * ":echon expr1 ..."	print each argument plain.
5747  */
5748     void
5749 ex_echo(exarg_T *eap)
5750 {
5751     char_u	*arg = eap->arg;
5752     typval_T	rettv;
5753     char_u	*p;
5754     int		needclr = TRUE;
5755     int		atstart = TRUE;
5756     int		did_emsg_before = did_emsg;
5757     int		called_emsg_before = called_emsg;
5758     evalarg_T	evalarg;
5759 
5760     fill_evalarg_from_eap(&evalarg, eap, eap->skip);
5761 
5762     if (eap->skip)
5763 	++emsg_skip;
5764     while ((!ends_excmd2(eap->cmd, arg) || *arg == '"') && !got_int)
5765     {
5766 	// If eval1() causes an error message the text from the command may
5767 	// still need to be cleared. E.g., "echo 22,44".
5768 	need_clr_eos = needclr;
5769 
5770 	p = arg;
5771 	if (eval1(&arg, &rettv, &evalarg) == FAIL)
5772 	{
5773 	    /*
5774 	     * Report the invalid expression unless the expression evaluation
5775 	     * has been cancelled due to an aborting error, an interrupt, or an
5776 	     * exception.
5777 	     */
5778 	    if (!aborting() && did_emsg == did_emsg_before
5779 					  && called_emsg == called_emsg_before)
5780 		semsg(_(e_invexpr2), p);
5781 	    need_clr_eos = FALSE;
5782 	    break;
5783 	}
5784 	need_clr_eos = FALSE;
5785 
5786 	if (!eap->skip)
5787 	    echo_one(&rettv, eap->cmdidx == CMD_echo, &atstart, &needclr);
5788 
5789 	clear_tv(&rettv);
5790 	arg = skipwhite(arg);
5791     }
5792     eap->nextcmd = check_nextcmd(arg);
5793     clear_evalarg(&evalarg, eap);
5794 
5795     if (eap->skip)
5796 	--emsg_skip;
5797     else
5798     {
5799 	// remove text that may still be there from the command
5800 	if (needclr)
5801 	    msg_clr_eos();
5802 	if (eap->cmdidx == CMD_echo)
5803 	    msg_end();
5804     }
5805 }
5806 
5807 /*
5808  * ":echohl {name}".
5809  */
5810     void
5811 ex_echohl(exarg_T *eap)
5812 {
5813     echo_attr = syn_name2attr(eap->arg);
5814 }
5815 
5816 /*
5817  * Returns the :echo attribute
5818  */
5819     int
5820 get_echo_attr(void)
5821 {
5822     return echo_attr;
5823 }
5824 
5825 /*
5826  * ":execute expr1 ..."	execute the result of an expression.
5827  * ":echomsg expr1 ..."	Print a message
5828  * ":echoerr expr1 ..."	Print an error
5829  * Each gets spaces around each argument and a newline at the end for
5830  * echo commands
5831  */
5832     void
5833 ex_execute(exarg_T *eap)
5834 {
5835     char_u	*arg = eap->arg;
5836     typval_T	rettv;
5837     int		ret = OK;
5838     char_u	*p;
5839     garray_T	ga;
5840     int		len;
5841 
5842     ga_init2(&ga, 1, 80);
5843 
5844     if (eap->skip)
5845 	++emsg_skip;
5846     while (!ends_excmd2(eap->cmd, arg) || *arg == '"')
5847     {
5848 	ret = eval1_emsg(&arg, &rettv, eap);
5849 	if (ret == FAIL)
5850 	    break;
5851 
5852 	if (!eap->skip)
5853 	{
5854 	    char_u   buf[NUMBUFLEN];
5855 
5856 	    if (eap->cmdidx == CMD_execute)
5857 	    {
5858 		if (rettv.v_type == VAR_CHANNEL || rettv.v_type == VAR_JOB)
5859 		{
5860 		    emsg(_(e_inval_string));
5861 		    p = NULL;
5862 		}
5863 		else
5864 		    p = tv_get_string_buf(&rettv, buf);
5865 	    }
5866 	    else
5867 		p = tv_stringify(&rettv, buf);
5868 	    if (p == NULL)
5869 	    {
5870 		clear_tv(&rettv);
5871 		ret = FAIL;
5872 		break;
5873 	    }
5874 	    len = (int)STRLEN(p);
5875 	    if (ga_grow(&ga, len + 2) == FAIL)
5876 	    {
5877 		clear_tv(&rettv);
5878 		ret = FAIL;
5879 		break;
5880 	    }
5881 	    if (ga.ga_len)
5882 		((char_u *)(ga.ga_data))[ga.ga_len++] = ' ';
5883 	    STRCPY((char_u *)(ga.ga_data) + ga.ga_len, p);
5884 	    ga.ga_len += len;
5885 	}
5886 
5887 	clear_tv(&rettv);
5888 	arg = skipwhite(arg);
5889     }
5890 
5891     if (ret != FAIL && ga.ga_data != NULL)
5892     {
5893 	if (eap->cmdidx == CMD_echomsg || eap->cmdidx == CMD_echoerr)
5894 	{
5895 	    // Mark the already saved text as finishing the line, so that what
5896 	    // follows is displayed on a new line when scrolling back at the
5897 	    // more prompt.
5898 	    msg_sb_eol();
5899 	}
5900 
5901 	if (eap->cmdidx == CMD_echomsg)
5902 	{
5903 	    msg_attr(ga.ga_data, echo_attr);
5904 	    out_flush();
5905 	}
5906 	else if (eap->cmdidx == CMD_echoerr)
5907 	{
5908 	    int		save_did_emsg = did_emsg;
5909 
5910 	    // We don't want to abort following commands, restore did_emsg.
5911 	    emsg(ga.ga_data);
5912 	    if (!force_abort)
5913 		did_emsg = save_did_emsg;
5914 	}
5915 	else if (eap->cmdidx == CMD_execute)
5916 	    do_cmdline((char_u *)ga.ga_data,
5917 		       eap->getline, eap->cookie, DOCMD_NOWAIT|DOCMD_VERBOSE);
5918     }
5919 
5920     ga_clear(&ga);
5921 
5922     if (eap->skip)
5923 	--emsg_skip;
5924 
5925     eap->nextcmd = check_nextcmd(arg);
5926 }
5927 
5928 /*
5929  * Skip over the name of an option: "&option", "&g:option" or "&l:option".
5930  * "arg" points to the "&" or '+' when called, to "option" when returning.
5931  * Returns NULL when no option name found.  Otherwise pointer to the char
5932  * after the option name.
5933  */
5934     char_u *
5935 find_option_end(char_u **arg, int *opt_flags)
5936 {
5937     char_u	*p = *arg;
5938 
5939     ++p;
5940     if (*p == 'g' && p[1] == ':')
5941     {
5942 	*opt_flags = OPT_GLOBAL;
5943 	p += 2;
5944     }
5945     else if (*p == 'l' && p[1] == ':')
5946     {
5947 	*opt_flags = OPT_LOCAL;
5948 	p += 2;
5949     }
5950     else
5951 	*opt_flags = 0;
5952 
5953     if (!ASCII_ISALPHA(*p))
5954 	return NULL;
5955     *arg = p;
5956 
5957     if (p[0] == 't' && p[1] == '_' && p[2] != NUL && p[3] != NUL)
5958 	p += 4;	    // termcap option
5959     else
5960 	while (ASCII_ISALPHA(*p))
5961 	    ++p;
5962     return p;
5963 }
5964 
5965 /*
5966  * Display script name where an item was last set.
5967  * Should only be invoked when 'verbose' is non-zero.
5968  */
5969     void
5970 last_set_msg(sctx_T script_ctx)
5971 {
5972     char_u *p;
5973 
5974     if (script_ctx.sc_sid != 0)
5975     {
5976 	p = home_replace_save(NULL, get_scriptname(script_ctx.sc_sid));
5977 	if (p != NULL)
5978 	{
5979 	    verbose_enter();
5980 	    msg_puts(_("\n\tLast set from "));
5981 	    msg_puts((char *)p);
5982 	    if (script_ctx.sc_lnum > 0)
5983 	    {
5984 		msg_puts(_(line_msg));
5985 		msg_outnum((long)script_ctx.sc_lnum);
5986 	    }
5987 	    verbose_leave();
5988 	    vim_free(p);
5989 	}
5990     }
5991 }
5992 
5993 #endif // FEAT_EVAL
5994 
5995 /*
5996  * Perform a substitution on "str" with pattern "pat" and substitute "sub".
5997  * When "sub" is NULL "expr" is used, must be a VAR_FUNC or VAR_PARTIAL.
5998  * "flags" can be "g" to do a global substitute.
5999  * Returns an allocated string, NULL for error.
6000  */
6001     char_u *
6002 do_string_sub(
6003     char_u	*str,
6004     char_u	*pat,
6005     char_u	*sub,
6006     typval_T	*expr,
6007     char_u	*flags)
6008 {
6009     int		sublen;
6010     regmatch_T	regmatch;
6011     int		i;
6012     int		do_all;
6013     char_u	*tail;
6014     char_u	*end;
6015     garray_T	ga;
6016     char_u	*ret;
6017     char_u	*save_cpo;
6018     char_u	*zero_width = NULL;
6019 
6020     // Make 'cpoptions' empty, so that the 'l' flag doesn't work here
6021     save_cpo = p_cpo;
6022     p_cpo = empty_option;
6023 
6024     ga_init2(&ga, 1, 200);
6025 
6026     do_all = (flags[0] == 'g');
6027 
6028     regmatch.rm_ic = p_ic;
6029     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
6030     if (regmatch.regprog != NULL)
6031     {
6032 	tail = str;
6033 	end = str + STRLEN(str);
6034 	while (vim_regexec_nl(&regmatch, str, (colnr_T)(tail - str)))
6035 	{
6036 	    // Skip empty match except for first match.
6037 	    if (regmatch.startp[0] == regmatch.endp[0])
6038 	    {
6039 		if (zero_width == regmatch.startp[0])
6040 		{
6041 		    // avoid getting stuck on a match with an empty string
6042 		    i = mb_ptr2len(tail);
6043 		    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail,
6044 								   (size_t)i);
6045 		    ga.ga_len += i;
6046 		    tail += i;
6047 		    continue;
6048 		}
6049 		zero_width = regmatch.startp[0];
6050 	    }
6051 
6052 	    /*
6053 	     * Get some space for a temporary buffer to do the substitution
6054 	     * into.  It will contain:
6055 	     * - The text up to where the match is.
6056 	     * - The substituted text.
6057 	     * - The text after the match.
6058 	     */
6059 	    sublen = vim_regsub(&regmatch, sub, expr, tail, FALSE, TRUE, FALSE);
6060 	    if (ga_grow(&ga, (int)((end - tail) + sublen -
6061 			    (regmatch.endp[0] - regmatch.startp[0]))) == FAIL)
6062 	    {
6063 		ga_clear(&ga);
6064 		break;
6065 	    }
6066 
6067 	    // copy the text up to where the match is
6068 	    i = (int)(regmatch.startp[0] - tail);
6069 	    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail, (size_t)i);
6070 	    // add the substituted text
6071 	    (void)vim_regsub(&regmatch, sub, expr, (char_u *)ga.ga_data
6072 					  + ga.ga_len + i, TRUE, TRUE, FALSE);
6073 	    ga.ga_len += i + sublen - 1;
6074 	    tail = regmatch.endp[0];
6075 	    if (*tail == NUL)
6076 		break;
6077 	    if (!do_all)
6078 		break;
6079 	}
6080 
6081 	if (ga.ga_data != NULL)
6082 	    STRCPY((char *)ga.ga_data + ga.ga_len, tail);
6083 
6084 	vim_regfree(regmatch.regprog);
6085     }
6086 
6087     ret = vim_strsave(ga.ga_data == NULL ? str : (char_u *)ga.ga_data);
6088     ga_clear(&ga);
6089     if (p_cpo == empty_option)
6090 	p_cpo = save_cpo;
6091     else
6092 	// Darn, evaluating {sub} expression or {expr} changed the value.
6093 	free_string_option(save_cpo);
6094 
6095     return ret;
6096 }
6097