xref: /vim-8.2.3635/src/eval.c (revision 147e7d0c)
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 DICT_MAXNEST 100	/* maximum nesting of lists and dicts */
24 
25 static char *e_letunexp	= N_("E18: Unexpected characters in :let");
26 static char *e_undefvar = N_("E121: Undefined variable: %s");
27 static char *e_missbrac = N_("E111: Missing ']'");
28 static char *e_dictrange = N_("E719: Cannot use [:] with a Dictionary");
29 static char *e_letwrong = N_("E734: Wrong variable type for %s=");
30 static char *e_illvar = N_("E461: Illegal variable name: %s");
31 #ifdef FEAT_FLOAT
32 static char *e_float_as_string = N_("E806: using Float as a String");
33 #endif
34 
35 #define NAMESPACE_CHAR	(char_u *)"abglstvw"
36 
37 static dictitem_T	globvars_var;		/* variable used for g: */
38 #define globvarht globvardict.dv_hashtab
39 
40 /*
41  * Old Vim variables such as "v:version" are also available without the "v:".
42  * Also in functions.  We need a special hashtable for them.
43  */
44 static hashtab_T	compat_hashtab;
45 
46 /*
47  * When recursively copying lists and dicts we need to remember which ones we
48  * have done to avoid endless recursiveness.  This unique ID is used for that.
49  * The last bit is used for previous_funccal, ignored when comparing.
50  */
51 static int current_copyID = 0;
52 
53 /*
54  * Array to hold the hashtab with variables local to each sourced script.
55  * Each item holds a variable (nameless) that points to the dict_T.
56  */
57 typedef struct
58 {
59     dictitem_T	sv_var;
60     dict_T	sv_dict;
61 } scriptvar_T;
62 
63 static garray_T	    ga_scripts = {0, 0, sizeof(scriptvar_T *), 4, NULL};
64 #define SCRIPT_SV(id) (((scriptvar_T **)ga_scripts.ga_data)[(id) - 1])
65 #define SCRIPT_VARS(id) (SCRIPT_SV(id)->sv_dict.dv_hashtab)
66 
67 static int echo_attr = 0;   /* attributes used for ":echo" */
68 
69 /* The names of packages that once were loaded are remembered. */
70 static garray_T		ga_loaded = {0, 0, sizeof(char_u *), 4, NULL};
71 
72 /*
73  * Info used by a ":for" loop.
74  */
75 typedef struct
76 {
77     int		fi_semicolon;	/* TRUE if ending in '; var]' */
78     int		fi_varcount;	/* nr of variables in the list */
79     listwatch_T	fi_lw;		/* keep an eye on the item used. */
80     list_T	*fi_list;	/* list being used */
81     int		fi_bi;		/* index of blob */
82     blob_T	*fi_blob;	/* blob being used */
83 } forinfo_T;
84 
85 
86 /*
87  * Array to hold the value of v: variables.
88  * The value is in a dictitem, so that it can also be used in the v: scope.
89  * The reason to use this table anyway is for very quick access to the
90  * variables with the VV_ defines.
91  */
92 
93 /* values for vv_flags: */
94 #define VV_COMPAT	1	/* compatible, also used without "v:" */
95 #define VV_RO		2	/* read-only */
96 #define VV_RO_SBX	4	/* read-only in the sandbox */
97 
98 #define VV_NAME(s, t)	s, {{t, 0, {0}}, 0, {0}}
99 
100 static struct vimvar
101 {
102     char	*vv_name;	/* name of variable, without v: */
103     dictitem16_T vv_di;		/* value and name for key (max 16 chars!) */
104     char	vv_flags;	/* VV_COMPAT, VV_RO, VV_RO_SBX */
105 } vimvars[VV_LEN] =
106 {
107     /*
108      * The order here must match the VV_ defines in vim.h!
109      * Initializing a union does not work, leave tv.vval empty to get zero's.
110      */
111     {VV_NAME("count",		 VAR_NUMBER), VV_COMPAT+VV_RO},
112     {VV_NAME("count1",		 VAR_NUMBER), VV_RO},
113     {VV_NAME("prevcount",	 VAR_NUMBER), VV_RO},
114     {VV_NAME("errmsg",		 VAR_STRING), VV_COMPAT},
115     {VV_NAME("warningmsg",	 VAR_STRING), 0},
116     {VV_NAME("statusmsg",	 VAR_STRING), 0},
117     {VV_NAME("shell_error",	 VAR_NUMBER), VV_COMPAT+VV_RO},
118     {VV_NAME("this_session",	 VAR_STRING), VV_COMPAT},
119     {VV_NAME("version",		 VAR_NUMBER), VV_COMPAT+VV_RO},
120     {VV_NAME("lnum",		 VAR_NUMBER), VV_RO_SBX},
121     {VV_NAME("termresponse",	 VAR_STRING), VV_RO},
122     {VV_NAME("fname",		 VAR_STRING), VV_RO},
123     {VV_NAME("lang",		 VAR_STRING), VV_RO},
124     {VV_NAME("lc_time",		 VAR_STRING), VV_RO},
125     {VV_NAME("ctype",		 VAR_STRING), VV_RO},
126     {VV_NAME("charconvert_from", VAR_STRING), VV_RO},
127     {VV_NAME("charconvert_to",	 VAR_STRING), VV_RO},
128     {VV_NAME("fname_in",	 VAR_STRING), VV_RO},
129     {VV_NAME("fname_out",	 VAR_STRING), VV_RO},
130     {VV_NAME("fname_new",	 VAR_STRING), VV_RO},
131     {VV_NAME("fname_diff",	 VAR_STRING), VV_RO},
132     {VV_NAME("cmdarg",		 VAR_STRING), VV_RO},
133     {VV_NAME("foldstart",	 VAR_NUMBER), VV_RO_SBX},
134     {VV_NAME("foldend",		 VAR_NUMBER), VV_RO_SBX},
135     {VV_NAME("folddashes",	 VAR_STRING), VV_RO_SBX},
136     {VV_NAME("foldlevel",	 VAR_NUMBER), VV_RO_SBX},
137     {VV_NAME("progname",	 VAR_STRING), VV_RO},
138     {VV_NAME("servername",	 VAR_STRING), VV_RO},
139     {VV_NAME("dying",		 VAR_NUMBER), VV_RO},
140     {VV_NAME("exception",	 VAR_STRING), VV_RO},
141     {VV_NAME("throwpoint",	 VAR_STRING), VV_RO},
142     {VV_NAME("register",	 VAR_STRING), VV_RO},
143     {VV_NAME("cmdbang",		 VAR_NUMBER), VV_RO},
144     {VV_NAME("insertmode",	 VAR_STRING), VV_RO},
145     {VV_NAME("val",		 VAR_UNKNOWN), VV_RO},
146     {VV_NAME("key",		 VAR_UNKNOWN), VV_RO},
147     {VV_NAME("profiling",	 VAR_NUMBER), VV_RO},
148     {VV_NAME("fcs_reason",	 VAR_STRING), VV_RO},
149     {VV_NAME("fcs_choice",	 VAR_STRING), 0},
150     {VV_NAME("beval_bufnr",	 VAR_NUMBER), VV_RO},
151     {VV_NAME("beval_winnr",	 VAR_NUMBER), VV_RO},
152     {VV_NAME("beval_winid",	 VAR_NUMBER), VV_RO},
153     {VV_NAME("beval_lnum",	 VAR_NUMBER), VV_RO},
154     {VV_NAME("beval_col",	 VAR_NUMBER), VV_RO},
155     {VV_NAME("beval_text",	 VAR_STRING), VV_RO},
156     {VV_NAME("scrollstart",	 VAR_STRING), 0},
157     {VV_NAME("swapname",	 VAR_STRING), VV_RO},
158     {VV_NAME("swapchoice",	 VAR_STRING), 0},
159     {VV_NAME("swapcommand",	 VAR_STRING), VV_RO},
160     {VV_NAME("char",		 VAR_STRING), 0},
161     {VV_NAME("mouse_win",	 VAR_NUMBER), 0},
162     {VV_NAME("mouse_winid",	 VAR_NUMBER), 0},
163     {VV_NAME("mouse_lnum",	 VAR_NUMBER), 0},
164     {VV_NAME("mouse_col",	 VAR_NUMBER), 0},
165     {VV_NAME("operator",	 VAR_STRING), VV_RO},
166     {VV_NAME("searchforward",	 VAR_NUMBER), 0},
167     {VV_NAME("hlsearch",	 VAR_NUMBER), 0},
168     {VV_NAME("oldfiles",	 VAR_LIST), 0},
169     {VV_NAME("windowid",	 VAR_NUMBER), VV_RO},
170     {VV_NAME("progpath",	 VAR_STRING), VV_RO},
171     {VV_NAME("completed_item",	 VAR_DICT), VV_RO},
172     {VV_NAME("option_new",	 VAR_STRING), VV_RO},
173     {VV_NAME("option_old",	 VAR_STRING), VV_RO},
174     {VV_NAME("option_type",	 VAR_STRING), VV_RO},
175     {VV_NAME("errors",		 VAR_LIST), 0},
176     {VV_NAME("false",		 VAR_SPECIAL), VV_RO},
177     {VV_NAME("true",		 VAR_SPECIAL), VV_RO},
178     {VV_NAME("null",		 VAR_SPECIAL), VV_RO},
179     {VV_NAME("none",		 VAR_SPECIAL), VV_RO},
180     {VV_NAME("vim_did_enter",	 VAR_NUMBER), VV_RO},
181     {VV_NAME("testing",		 VAR_NUMBER), 0},
182     {VV_NAME("t_number",	 VAR_NUMBER), VV_RO},
183     {VV_NAME("t_string",	 VAR_NUMBER), VV_RO},
184     {VV_NAME("t_func",		 VAR_NUMBER), VV_RO},
185     {VV_NAME("t_list",		 VAR_NUMBER), VV_RO},
186     {VV_NAME("t_dict",		 VAR_NUMBER), VV_RO},
187     {VV_NAME("t_float",		 VAR_NUMBER), VV_RO},
188     {VV_NAME("t_bool",		 VAR_NUMBER), VV_RO},
189     {VV_NAME("t_none",		 VAR_NUMBER), VV_RO},
190     {VV_NAME("t_job",		 VAR_NUMBER), VV_RO},
191     {VV_NAME("t_channel",	 VAR_NUMBER), VV_RO},
192     {VV_NAME("t_blob",		 VAR_NUMBER), VV_RO},
193     {VV_NAME("termrfgresp",	 VAR_STRING), VV_RO},
194     {VV_NAME("termrbgresp",	 VAR_STRING), VV_RO},
195     {VV_NAME("termu7resp",	 VAR_STRING), VV_RO},
196     {VV_NAME("termstyleresp",	VAR_STRING), VV_RO},
197     {VV_NAME("termblinkresp",	VAR_STRING), VV_RO},
198     {VV_NAME("event",		VAR_DICT), VV_RO},
199 };
200 
201 /* shorthand */
202 #define vv_type		vv_di.di_tv.v_type
203 #define vv_nr		vv_di.di_tv.vval.v_number
204 #define vv_float	vv_di.di_tv.vval.v_float
205 #define vv_str		vv_di.di_tv.vval.v_string
206 #define vv_list		vv_di.di_tv.vval.v_list
207 #define vv_dict		vv_di.di_tv.vval.v_dict
208 #define vv_blob		vv_di.di_tv.vval.v_blob
209 #define vv_tv		vv_di.di_tv
210 
211 static dictitem_T	vimvars_var;		/* variable used for v: */
212 #define vimvarht  vimvardict.dv_hashtab
213 
214 static int ex_let_vars(char_u *arg, typval_T *tv, int copy, int semicolon, int var_count, char_u *nextchars);
215 static char_u *skip_var_list(char_u *arg, int *var_count, int *semicolon);
216 static char_u *skip_var_one(char_u *arg);
217 static void list_glob_vars(int *first);
218 static void list_buf_vars(int *first);
219 static void list_win_vars(int *first);
220 static void list_tab_vars(int *first);
221 static void list_vim_vars(int *first);
222 static void list_script_vars(int *first);
223 static char_u *list_arg_vars(exarg_T *eap, char_u *arg, int *first);
224 static char_u *ex_let_one(char_u *arg, typval_T *tv, int copy, char_u *endchars, char_u *op);
225 static void set_var_lval(lval_T *lp, char_u *endp, typval_T *rettv, int copy, char_u *op);
226 static int tv_op(typval_T *tv1, typval_T *tv2, char_u  *op);
227 static void ex_unletlock(exarg_T *eap, char_u *argstart, int deep);
228 static int do_unlet_var(lval_T *lp, char_u *name_end, int forceit);
229 static int do_lock_var(lval_T *lp, char_u *name_end, int deep, int lock);
230 static void item_lock(typval_T *tv, int deep, int lock);
231 
232 static int eval2(char_u **arg, typval_T *rettv, int evaluate);
233 static int eval3(char_u **arg, typval_T *rettv, int evaluate);
234 static int eval4(char_u **arg, typval_T *rettv, int evaluate);
235 static int eval5(char_u **arg, typval_T *rettv, int evaluate);
236 static int eval6(char_u **arg, typval_T *rettv, int evaluate, int want_string);
237 static int eval7(char_u **arg, typval_T *rettv, int evaluate, int want_string);
238 
239 static int get_string_tv(char_u **arg, typval_T *rettv, int evaluate);
240 static int get_lit_string_tv(char_u **arg, typval_T *rettv, int evaluate);
241 static int free_unref_items(int copyID);
242 static int get_env_tv(char_u **arg, typval_T *rettv, int evaluate);
243 static int get_env_len(char_u **arg);
244 static char_u * make_expanded_name(char_u *in_start, char_u *expr_start, char_u *expr_end, char_u *in_end);
245 static void check_vars(char_u *name, int len);
246 static typval_T *alloc_string_tv(char_u *string);
247 static void delete_var(hashtab_T *ht, hashitem_T *hi);
248 static void list_one_var(dictitem_T *v, char_u *prefix, int *first);
249 static void list_one_var_a(char_u *prefix, char_u *name, int type, char_u *string, int *first);
250 static char_u *find_option_end(char_u **arg, int *opt_flags);
251 
252 /* for VIM_VERSION_ defines */
253 #include "version.h"
254 
255 
256 #if defined(EBCDIC) || defined(PROTO)
257 /*
258  * Compare struct fst by function name.
259  */
260     static int
261 compare_func_name(const void *s1, const void *s2)
262 {
263     struct fst *p1 = (struct fst *)s1;
264     struct fst *p2 = (struct fst *)s2;
265 
266     return STRCMP(p1->f_name, p2->f_name);
267 }
268 
269 /*
270  * Sort the function table by function name.
271  * The sorting of the table above is ASCII dependent.
272  * On machines using EBCDIC we have to sort it.
273  */
274     static void
275 sortFunctions(void)
276 {
277     int		funcCnt = (int)(sizeof(functions) / sizeof(struct fst)) - 1;
278 
279     qsort(functions, (size_t)funcCnt, sizeof(struct fst), compare_func_name);
280 }
281 #endif
282 
283 
284 /*
285  * Initialize the global and v: variables.
286  */
287     void
288 eval_init(void)
289 {
290     int		    i;
291     struct vimvar   *p;
292 
293     init_var_dict(&globvardict, &globvars_var, VAR_DEF_SCOPE);
294     init_var_dict(&vimvardict, &vimvars_var, VAR_SCOPE);
295     vimvardict.dv_lock = VAR_FIXED;
296     hash_init(&compat_hashtab);
297     func_init();
298 
299     for (i = 0; i < VV_LEN; ++i)
300     {
301 	p = &vimvars[i];
302 	if (STRLEN(p->vv_name) > 16)
303 	{
304 	    iemsg("INTERNAL: name too long, increase size of dictitem16_T");
305 	    getout(1);
306 	}
307 	STRCPY(p->vv_di.di_key, p->vv_name);
308 	if (p->vv_flags & VV_RO)
309 	    p->vv_di.di_flags = DI_FLAGS_RO | DI_FLAGS_FIX;
310 	else if (p->vv_flags & VV_RO_SBX)
311 	    p->vv_di.di_flags = DI_FLAGS_RO_SBX | DI_FLAGS_FIX;
312 	else
313 	    p->vv_di.di_flags = DI_FLAGS_FIX;
314 
315 	/* add to v: scope dict, unless the value is not always available */
316 	if (p->vv_type != VAR_UNKNOWN)
317 	    hash_add(&vimvarht, p->vv_di.di_key);
318 	if (p->vv_flags & VV_COMPAT)
319 	    /* add to compat scope dict */
320 	    hash_add(&compat_hashtab, p->vv_di.di_key);
321     }
322     vimvars[VV_VERSION].vv_nr = VIM_VERSION_100;
323 
324     set_vim_var_nr(VV_SEARCHFORWARD, 1L);
325     set_vim_var_nr(VV_HLSEARCH, 1L);
326     set_vim_var_dict(VV_COMPLETED_ITEM, dict_alloc_lock(VAR_FIXED));
327     set_vim_var_list(VV_ERRORS, list_alloc());
328     set_vim_var_dict(VV_EVENT, dict_alloc_lock(VAR_FIXED));
329 
330     set_vim_var_nr(VV_FALSE, VVAL_FALSE);
331     set_vim_var_nr(VV_TRUE, VVAL_TRUE);
332     set_vim_var_nr(VV_NONE, VVAL_NONE);
333     set_vim_var_nr(VV_NULL, VVAL_NULL);
334 
335     set_vim_var_nr(VV_TYPE_NUMBER,  VAR_TYPE_NUMBER);
336     set_vim_var_nr(VV_TYPE_STRING,  VAR_TYPE_STRING);
337     set_vim_var_nr(VV_TYPE_FUNC,    VAR_TYPE_FUNC);
338     set_vim_var_nr(VV_TYPE_LIST,    VAR_TYPE_LIST);
339     set_vim_var_nr(VV_TYPE_DICT,    VAR_TYPE_DICT);
340     set_vim_var_nr(VV_TYPE_FLOAT,   VAR_TYPE_FLOAT);
341     set_vim_var_nr(VV_TYPE_BOOL,    VAR_TYPE_BOOL);
342     set_vim_var_nr(VV_TYPE_NONE,    VAR_TYPE_NONE);
343     set_vim_var_nr(VV_TYPE_JOB,     VAR_TYPE_JOB);
344     set_vim_var_nr(VV_TYPE_CHANNEL, VAR_TYPE_CHANNEL);
345     set_vim_var_nr(VV_TYPE_BLOB,    VAR_TYPE_BLOB);
346 
347     set_reg_var(0);  /* default for v:register is not 0 but '"' */
348 
349 #ifdef EBCDIC
350     /*
351      * Sort the function table, to enable binary search.
352      */
353     sortFunctions();
354 #endif
355 }
356 
357 #if defined(EXITFREE) || defined(PROTO)
358     void
359 eval_clear(void)
360 {
361     int		    i;
362     struct vimvar   *p;
363 
364     for (i = 0; i < VV_LEN; ++i)
365     {
366 	p = &vimvars[i];
367 	if (p->vv_di.di_tv.v_type == VAR_STRING)
368 	    VIM_CLEAR(p->vv_str);
369 	else if (p->vv_di.di_tv.v_type == VAR_LIST)
370 	{
371 	    list_unref(p->vv_list);
372 	    p->vv_list = NULL;
373 	}
374     }
375     hash_clear(&vimvarht);
376     hash_init(&vimvarht);  /* garbage_collect() will access it */
377     hash_clear(&compat_hashtab);
378 
379     free_scriptnames();
380 # if defined(FEAT_CMDL_COMPL)
381     free_locales();
382 # endif
383 
384     /* global variables */
385     vars_clear(&globvarht);
386 
387     /* autoloaded script names */
388     ga_clear_strings(&ga_loaded);
389 
390     /* Script-local variables. First clear all the variables and in a second
391      * loop free the scriptvar_T, because a variable in one script might hold
392      * a reference to the whole scope of another script. */
393     for (i = 1; i <= ga_scripts.ga_len; ++i)
394 	vars_clear(&SCRIPT_VARS(i));
395     for (i = 1; i <= ga_scripts.ga_len; ++i)
396 	vim_free(SCRIPT_SV(i));
397     ga_clear(&ga_scripts);
398 
399     /* unreferenced lists and dicts */
400     (void)garbage_collect(FALSE);
401 
402     /* functions */
403     free_all_functions();
404 }
405 #endif
406 
407 
408 /*
409  * Set an internal variable to a string value. Creates the variable if it does
410  * not already exist.
411  */
412     void
413 set_internal_string_var(char_u *name, char_u *value)
414 {
415     char_u	*val;
416     typval_T	*tvp;
417 
418     val = vim_strsave(value);
419     if (val != NULL)
420     {
421 	tvp = alloc_string_tv(val);
422 	if (tvp != NULL)
423 	{
424 	    set_var(name, tvp, FALSE);
425 	    free_tv(tvp);
426 	}
427     }
428 }
429 
430 static lval_T	*redir_lval = NULL;
431 #define EVALCMD_BUSY (redir_lval == (lval_T *)&redir_lval)
432 static garray_T redir_ga;	/* only valid when redir_lval is not NULL */
433 static char_u	*redir_endp = NULL;
434 static char_u	*redir_varname = NULL;
435 
436 /*
437  * Start recording command output to a variable
438  * When "append" is TRUE append to an existing variable.
439  * Returns OK if successfully completed the setup.  FAIL otherwise.
440  */
441     int
442 var_redir_start(char_u *name, int append)
443 {
444     int		save_emsg;
445     int		err;
446     typval_T	tv;
447 
448     /* Catch a bad name early. */
449     if (!eval_isnamec1(*name))
450     {
451 	emsg(_(e_invarg));
452 	return FAIL;
453     }
454 
455     /* Make a copy of the name, it is used in redir_lval until redir ends. */
456     redir_varname = vim_strsave(name);
457     if (redir_varname == NULL)
458 	return FAIL;
459 
460     redir_lval = (lval_T *)alloc_clear((unsigned)sizeof(lval_T));
461     if (redir_lval == NULL)
462     {
463 	var_redir_stop();
464 	return FAIL;
465     }
466 
467     /* The output is stored in growarray "redir_ga" until redirection ends. */
468     ga_init2(&redir_ga, (int)sizeof(char), 500);
469 
470     /* Parse the variable name (can be a dict or list entry). */
471     redir_endp = get_lval(redir_varname, NULL, redir_lval, FALSE, FALSE, 0,
472 							     FNE_CHECK_START);
473     if (redir_endp == NULL || redir_lval->ll_name == NULL || *redir_endp != NUL)
474     {
475 	clear_lval(redir_lval);
476 	if (redir_endp != NULL && *redir_endp != NUL)
477 	    /* Trailing characters are present after the variable name */
478 	    emsg(_(e_trailing));
479 	else
480 	    emsg(_(e_invarg));
481 	redir_endp = NULL;  /* don't store a value, only cleanup */
482 	var_redir_stop();
483 	return FAIL;
484     }
485 
486     /* check if we can write to the variable: set it to or append an empty
487      * string */
488     save_emsg = did_emsg;
489     did_emsg = FALSE;
490     tv.v_type = VAR_STRING;
491     tv.vval.v_string = (char_u *)"";
492     if (append)
493 	set_var_lval(redir_lval, redir_endp, &tv, TRUE, (char_u *)".");
494     else
495 	set_var_lval(redir_lval, redir_endp, &tv, TRUE, (char_u *)"=");
496     clear_lval(redir_lval);
497     err = did_emsg;
498     did_emsg |= save_emsg;
499     if (err)
500     {
501 	redir_endp = NULL;  /* don't store a value, only cleanup */
502 	var_redir_stop();
503 	return FAIL;
504     }
505 
506     return OK;
507 }
508 
509 /*
510  * Append "value[value_len]" to the variable set by var_redir_start().
511  * The actual appending is postponed until redirection ends, because the value
512  * appended may in fact be the string we write to, changing it may cause freed
513  * memory to be used:
514  *   :redir => foo
515  *   :let foo
516  *   :redir END
517  */
518     void
519 var_redir_str(char_u *value, int value_len)
520 {
521     int		len;
522 
523     if (redir_lval == NULL)
524 	return;
525 
526     if (value_len == -1)
527 	len = (int)STRLEN(value);	/* Append the entire string */
528     else
529 	len = value_len;		/* Append only "value_len" characters */
530 
531     if (ga_grow(&redir_ga, len) == OK)
532     {
533 	mch_memmove((char *)redir_ga.ga_data + redir_ga.ga_len, value, len);
534 	redir_ga.ga_len += len;
535     }
536     else
537 	var_redir_stop();
538 }
539 
540 /*
541  * Stop redirecting command output to a variable.
542  * Frees the allocated memory.
543  */
544     void
545 var_redir_stop(void)
546 {
547     typval_T	tv;
548 
549     if (EVALCMD_BUSY)
550     {
551 	redir_lval = NULL;
552 	return;
553     }
554 
555     if (redir_lval != NULL)
556     {
557 	/* If there was no error: assign the text to the variable. */
558 	if (redir_endp != NULL)
559 	{
560 	    ga_append(&redir_ga, NUL);  /* Append the trailing NUL. */
561 	    tv.v_type = VAR_STRING;
562 	    tv.vval.v_string = redir_ga.ga_data;
563 	    /* Call get_lval() again, if it's inside a Dict or List it may
564 	     * have changed. */
565 	    redir_endp = get_lval(redir_varname, NULL, redir_lval,
566 					FALSE, FALSE, 0, FNE_CHECK_START);
567 	    if (redir_endp != NULL && redir_lval->ll_name != NULL)
568 		set_var_lval(redir_lval, redir_endp, &tv, FALSE, (char_u *)".");
569 	    clear_lval(redir_lval);
570 	}
571 
572 	/* free the collected output */
573 	VIM_CLEAR(redir_ga.ga_data);
574 
575 	VIM_CLEAR(redir_lval);
576     }
577     VIM_CLEAR(redir_varname);
578 }
579 
580 # if defined(FEAT_MBYTE) || defined(PROTO)
581     int
582 eval_charconvert(
583     char_u	*enc_from,
584     char_u	*enc_to,
585     char_u	*fname_from,
586     char_u	*fname_to)
587 {
588     int		err = FALSE;
589 
590     set_vim_var_string(VV_CC_FROM, enc_from, -1);
591     set_vim_var_string(VV_CC_TO, enc_to, -1);
592     set_vim_var_string(VV_FNAME_IN, fname_from, -1);
593     set_vim_var_string(VV_FNAME_OUT, fname_to, -1);
594     if (eval_to_bool(p_ccv, &err, NULL, FALSE))
595 	err = TRUE;
596     set_vim_var_string(VV_CC_FROM, NULL, -1);
597     set_vim_var_string(VV_CC_TO, NULL, -1);
598     set_vim_var_string(VV_FNAME_IN, NULL, -1);
599     set_vim_var_string(VV_FNAME_OUT, NULL, -1);
600 
601     if (err)
602 	return FAIL;
603     return OK;
604 }
605 # endif
606 
607 # if defined(FEAT_POSTSCRIPT) || defined(PROTO)
608     int
609 eval_printexpr(char_u *fname, char_u *args)
610 {
611     int		err = FALSE;
612 
613     set_vim_var_string(VV_FNAME_IN, fname, -1);
614     set_vim_var_string(VV_CMDARG, args, -1);
615     if (eval_to_bool(p_pexpr, &err, NULL, FALSE))
616 	err = TRUE;
617     set_vim_var_string(VV_FNAME_IN, NULL, -1);
618     set_vim_var_string(VV_CMDARG, NULL, -1);
619 
620     if (err)
621     {
622 	mch_remove(fname);
623 	return FAIL;
624     }
625     return OK;
626 }
627 # endif
628 
629 # if defined(FEAT_DIFF) || defined(PROTO)
630     void
631 eval_diff(
632     char_u	*origfile,
633     char_u	*newfile,
634     char_u	*outfile)
635 {
636     int		err = FALSE;
637 
638     set_vim_var_string(VV_FNAME_IN, origfile, -1);
639     set_vim_var_string(VV_FNAME_NEW, newfile, -1);
640     set_vim_var_string(VV_FNAME_OUT, outfile, -1);
641     (void)eval_to_bool(p_dex, &err, NULL, FALSE);
642     set_vim_var_string(VV_FNAME_IN, NULL, -1);
643     set_vim_var_string(VV_FNAME_NEW, NULL, -1);
644     set_vim_var_string(VV_FNAME_OUT, NULL, -1);
645 }
646 
647     void
648 eval_patch(
649     char_u	*origfile,
650     char_u	*difffile,
651     char_u	*outfile)
652 {
653     int		err;
654 
655     set_vim_var_string(VV_FNAME_IN, origfile, -1);
656     set_vim_var_string(VV_FNAME_DIFF, difffile, -1);
657     set_vim_var_string(VV_FNAME_OUT, outfile, -1);
658     (void)eval_to_bool(p_pex, &err, NULL, FALSE);
659     set_vim_var_string(VV_FNAME_IN, NULL, -1);
660     set_vim_var_string(VV_FNAME_DIFF, NULL, -1);
661     set_vim_var_string(VV_FNAME_OUT, NULL, -1);
662 }
663 # endif
664 
665 /*
666  * Top level evaluation function, returning a boolean.
667  * Sets "error" to TRUE if there was an error.
668  * Return TRUE or FALSE.
669  */
670     int
671 eval_to_bool(
672     char_u	*arg,
673     int		*error,
674     char_u	**nextcmd,
675     int		skip)	    /* only parse, don't execute */
676 {
677     typval_T	tv;
678     varnumber_T	retval = FALSE;
679 
680     if (skip)
681 	++emsg_skip;
682     if (eval0(arg, &tv, nextcmd, !skip) == FAIL)
683 	*error = TRUE;
684     else
685     {
686 	*error = FALSE;
687 	if (!skip)
688 	{
689 	    retval = (tv_get_number_chk(&tv, error) != 0);
690 	    clear_tv(&tv);
691 	}
692     }
693     if (skip)
694 	--emsg_skip;
695 
696     return (int)retval;
697 }
698 
699 /*
700  * Call eval1() and give an error message if not done at a lower level.
701  */
702     static int
703 eval1_emsg(char_u **arg, typval_T *rettv, int evaluate)
704 {
705     char_u	*start = *arg;
706     int		ret;
707     int		did_emsg_before = did_emsg;
708     int		called_emsg_before = called_emsg;
709 
710     ret = eval1(arg, rettv, evaluate);
711     if (ret == FAIL)
712     {
713 	// Report the invalid expression unless the expression evaluation has
714 	// been cancelled due to an aborting error, an interrupt, or an
715 	// exception, or we already gave a more specific error.
716 	// Also check called_emsg for when using assert_fails().
717 	if (!aborting() && did_emsg == did_emsg_before
718 					  && called_emsg == called_emsg_before)
719 	    semsg(_(e_invexpr2), start);
720     }
721     return ret;
722 }
723 
724     static int
725 eval_expr_typval(typval_T *expr, typval_T *argv, int argc, typval_T *rettv)
726 {
727     char_u	*s;
728     int		dummy;
729     char_u	buf[NUMBUFLEN];
730 
731     if (expr->v_type == VAR_FUNC)
732     {
733 	s = expr->vval.v_string;
734 	if (s == NULL || *s == NUL)
735 	    return FAIL;
736 	if (call_func(s, (int)STRLEN(s), rettv, argc, argv, NULL,
737 				     0L, 0L, &dummy, TRUE, NULL, NULL) == FAIL)
738 	    return FAIL;
739     }
740     else if (expr->v_type == VAR_PARTIAL)
741     {
742 	partial_T   *partial = expr->vval.v_partial;
743 
744 	s = partial_name(partial);
745 	if (s == NULL || *s == NUL)
746 	    return FAIL;
747 	if (call_func(s, (int)STRLEN(s), rettv, argc, argv, NULL,
748 				  0L, 0L, &dummy, TRUE, partial, NULL) == FAIL)
749 	    return FAIL;
750     }
751     else
752     {
753 	s = tv_get_string_buf_chk(expr, buf);
754 	if (s == NULL)
755 	    return FAIL;
756 	s = skipwhite(s);
757 	if (eval1_emsg(&s, rettv, TRUE) == FAIL)
758 	    return FAIL;
759 	if (*s != NUL)  /* check for trailing chars after expr */
760 	{
761 	    clear_tv(rettv);
762 	    semsg(_(e_invexpr2), s);
763 	    return FAIL;
764 	}
765     }
766     return OK;
767 }
768 
769 /*
770  * Like eval_to_bool() but using a typval_T instead of a string.
771  * Works for string, funcref and partial.
772  */
773     int
774 eval_expr_to_bool(typval_T *expr, int *error)
775 {
776     typval_T	rettv;
777     int		res;
778 
779     if (eval_expr_typval(expr, NULL, 0, &rettv) == FAIL)
780     {
781 	*error = TRUE;
782 	return FALSE;
783     }
784     res = (tv_get_number_chk(&rettv, error) != 0);
785     clear_tv(&rettv);
786     return res;
787 }
788 
789 /*
790  * Top level evaluation function, returning a string.  If "skip" is TRUE,
791  * only parsing to "nextcmd" is done, without reporting errors.  Return
792  * pointer to allocated memory, or NULL for failure or when "skip" is TRUE.
793  */
794     char_u *
795 eval_to_string_skip(
796     char_u	*arg,
797     char_u	**nextcmd,
798     int		skip)	    /* only parse, don't execute */
799 {
800     typval_T	tv;
801     char_u	*retval;
802 
803     if (skip)
804 	++emsg_skip;
805     if (eval0(arg, &tv, nextcmd, !skip) == FAIL || skip)
806 	retval = NULL;
807     else
808     {
809 	retval = vim_strsave(tv_get_string(&tv));
810 	clear_tv(&tv);
811     }
812     if (skip)
813 	--emsg_skip;
814 
815     return retval;
816 }
817 
818 /*
819  * Skip over an expression at "*pp".
820  * Return FAIL for an error, OK otherwise.
821  */
822     int
823 skip_expr(char_u **pp)
824 {
825     typval_T	rettv;
826 
827     *pp = skipwhite(*pp);
828     return eval1(pp, &rettv, FALSE);
829 }
830 
831 /*
832  * Top level evaluation function, returning a string.
833  * When "convert" is TRUE convert a List into a sequence of lines and convert
834  * a Float to a String.
835  * Return pointer to allocated memory, or NULL for failure.
836  */
837     char_u *
838 eval_to_string(
839     char_u	*arg,
840     char_u	**nextcmd,
841     int		convert)
842 {
843     typval_T	tv;
844     char_u	*retval;
845     garray_T	ga;
846 #ifdef FEAT_FLOAT
847     char_u	numbuf[NUMBUFLEN];
848 #endif
849 
850     if (eval0(arg, &tv, nextcmd, TRUE) == FAIL)
851 	retval = NULL;
852     else
853     {
854 	if (convert && tv.v_type == VAR_LIST)
855 	{
856 	    ga_init2(&ga, (int)sizeof(char), 80);
857 	    if (tv.vval.v_list != NULL)
858 	    {
859 		list_join(&ga, tv.vval.v_list, (char_u *)"\n", TRUE, FALSE, 0);
860 		if (tv.vval.v_list->lv_len > 0)
861 		    ga_append(&ga, NL);
862 	    }
863 	    ga_append(&ga, NUL);
864 	    retval = (char_u *)ga.ga_data;
865 	}
866 #ifdef FEAT_FLOAT
867 	else if (convert && tv.v_type == VAR_FLOAT)
868 	{
869 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv.vval.v_float);
870 	    retval = vim_strsave(numbuf);
871 	}
872 #endif
873 	else
874 	    retval = vim_strsave(tv_get_string(&tv));
875 	clear_tv(&tv);
876     }
877 
878     return retval;
879 }
880 
881 /*
882  * Call eval_to_string() without using current local variables and using
883  * textlock.  When "use_sandbox" is TRUE use the sandbox.
884  */
885     char_u *
886 eval_to_string_safe(
887     char_u	*arg,
888     char_u	**nextcmd,
889     int		use_sandbox)
890 {
891     char_u	*retval;
892     funccal_entry_T funccal_entry;
893 
894     save_funccal(&funccal_entry);
895     if (use_sandbox)
896 	++sandbox;
897     ++textlock;
898     retval = eval_to_string(arg, nextcmd, FALSE);
899     if (use_sandbox)
900 	--sandbox;
901     --textlock;
902     restore_funccal();
903     return retval;
904 }
905 
906 /*
907  * Top level evaluation function, returning a number.
908  * Evaluates "expr" silently.
909  * Returns -1 for an error.
910  */
911     varnumber_T
912 eval_to_number(char_u *expr)
913 {
914     typval_T	rettv;
915     varnumber_T	retval;
916     char_u	*p = skipwhite(expr);
917 
918     ++emsg_off;
919 
920     if (eval1(&p, &rettv, TRUE) == FAIL)
921 	retval = -1;
922     else
923     {
924 	retval = tv_get_number_chk(&rettv, NULL);
925 	clear_tv(&rettv);
926     }
927     --emsg_off;
928 
929     return retval;
930 }
931 
932 /*
933  * Prepare v: variable "idx" to be used.
934  * Save the current typeval in "save_tv".
935  * When not used yet add the variable to the v: hashtable.
936  */
937     static void
938 prepare_vimvar(int idx, typval_T *save_tv)
939 {
940     *save_tv = vimvars[idx].vv_tv;
941     if (vimvars[idx].vv_type == VAR_UNKNOWN)
942 	hash_add(&vimvarht, vimvars[idx].vv_di.di_key);
943 }
944 
945 /*
946  * Restore v: variable "idx" to typeval "save_tv".
947  * When no longer defined, remove the variable from the v: hashtable.
948  */
949     static void
950 restore_vimvar(int idx, typval_T *save_tv)
951 {
952     hashitem_T	*hi;
953 
954     vimvars[idx].vv_tv = *save_tv;
955     if (vimvars[idx].vv_type == VAR_UNKNOWN)
956     {
957 	hi = hash_find(&vimvarht, vimvars[idx].vv_di.di_key);
958 	if (HASHITEM_EMPTY(hi))
959 	    internal_error("restore_vimvar()");
960 	else
961 	    hash_remove(&vimvarht, hi);
962     }
963 }
964 
965 #if defined(FEAT_SPELL) || defined(PROTO)
966 /*
967  * Evaluate an expression to a list with suggestions.
968  * For the "expr:" part of 'spellsuggest'.
969  * Returns NULL when there is an error.
970  */
971     list_T *
972 eval_spell_expr(char_u *badword, char_u *expr)
973 {
974     typval_T	save_val;
975     typval_T	rettv;
976     list_T	*list = NULL;
977     char_u	*p = skipwhite(expr);
978 
979     /* Set "v:val" to the bad word. */
980     prepare_vimvar(VV_VAL, &save_val);
981     vimvars[VV_VAL].vv_type = VAR_STRING;
982     vimvars[VV_VAL].vv_str = badword;
983     if (p_verbose == 0)
984 	++emsg_off;
985 
986     if (eval1(&p, &rettv, TRUE) == OK)
987     {
988 	if (rettv.v_type != VAR_LIST)
989 	    clear_tv(&rettv);
990 	else
991 	    list = rettv.vval.v_list;
992     }
993 
994     if (p_verbose == 0)
995 	--emsg_off;
996     restore_vimvar(VV_VAL, &save_val);
997 
998     return list;
999 }
1000 
1001 /*
1002  * "list" is supposed to contain two items: a word and a number.  Return the
1003  * word in "pp" and the number as the return value.
1004  * Return -1 if anything isn't right.
1005  * Used to get the good word and score from the eval_spell_expr() result.
1006  */
1007     int
1008 get_spellword(list_T *list, char_u **pp)
1009 {
1010     listitem_T	*li;
1011 
1012     li = list->lv_first;
1013     if (li == NULL)
1014 	return -1;
1015     *pp = tv_get_string(&li->li_tv);
1016 
1017     li = li->li_next;
1018     if (li == NULL)
1019 	return -1;
1020     return (int)tv_get_number(&li->li_tv);
1021 }
1022 #endif
1023 
1024 /*
1025  * Top level evaluation function.
1026  * Returns an allocated typval_T with the result.
1027  * Returns NULL when there is an error.
1028  */
1029     typval_T *
1030 eval_expr(char_u *arg, char_u **nextcmd)
1031 {
1032     typval_T	*tv;
1033 
1034     tv = (typval_T *)alloc(sizeof(typval_T));
1035     if (tv != NULL && eval0(arg, tv, nextcmd, TRUE) == FAIL)
1036 	VIM_CLEAR(tv);
1037 
1038     return tv;
1039 }
1040 
1041 
1042 /*
1043  * Call some Vim script function and return the result in "*rettv".
1044  * Uses argv[0] to argv[argc - 1] for the function arguments.  argv[argc]
1045  * should have type VAR_UNKNOWN.
1046  * Returns OK or FAIL.
1047  */
1048     int
1049 call_vim_function(
1050     char_u      *func,
1051     int		argc,
1052     typval_T	*argv,
1053     typval_T	*rettv)
1054 {
1055     int		doesrange;
1056     int		ret;
1057 
1058     rettv->v_type = VAR_UNKNOWN;		/* clear_tv() uses this */
1059     ret = call_func(func, (int)STRLEN(func), rettv, argc, argv, NULL,
1060 		    curwin->w_cursor.lnum, curwin->w_cursor.lnum,
1061 		    &doesrange, TRUE, NULL, NULL);
1062     if (ret == FAIL)
1063 	clear_tv(rettv);
1064 
1065     return ret;
1066 }
1067 
1068 /*
1069  * Call Vim script function "func" and return the result as a number.
1070  * Returns -1 when calling the function fails.
1071  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
1072  * have type VAR_UNKNOWN.
1073  */
1074     varnumber_T
1075 call_func_retnr(
1076     char_u      *func,
1077     int		argc,
1078     typval_T	*argv)
1079 {
1080     typval_T	rettv;
1081     varnumber_T	retval;
1082 
1083     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
1084 	return -1;
1085 
1086     retval = tv_get_number_chk(&rettv, NULL);
1087     clear_tv(&rettv);
1088     return retval;
1089 }
1090 
1091 #if (defined(FEAT_USR_CMDS) && defined(FEAT_CMDL_COMPL)) \
1092 	|| defined(FEAT_COMPL_FUNC) || defined(PROTO)
1093 
1094 # if (defined(FEAT_USR_CMDS) && defined(FEAT_CMDL_COMPL)) || defined(PROTO)
1095 /*
1096  * Call Vim script function "func" and return the result as a string.
1097  * Returns NULL when calling the function fails.
1098  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
1099  * have type VAR_UNKNOWN.
1100  */
1101     void *
1102 call_func_retstr(
1103     char_u      *func,
1104     int		argc,
1105     typval_T	*argv)
1106 {
1107     typval_T	rettv;
1108     char_u	*retval;
1109 
1110     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
1111 	return NULL;
1112 
1113     retval = vim_strsave(tv_get_string(&rettv));
1114     clear_tv(&rettv);
1115     return retval;
1116 }
1117 # endif
1118 
1119 /*
1120  * Call Vim script function "func" and return the result as a List.
1121  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
1122  * have type VAR_UNKNOWN.
1123  * Returns NULL when there is something wrong.
1124  */
1125     void *
1126 call_func_retlist(
1127     char_u      *func,
1128     int		argc,
1129     typval_T	*argv)
1130 {
1131     typval_T	rettv;
1132 
1133     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
1134 	return NULL;
1135 
1136     if (rettv.v_type != VAR_LIST)
1137     {
1138 	clear_tv(&rettv);
1139 	return NULL;
1140     }
1141 
1142     return rettv.vval.v_list;
1143 }
1144 #endif
1145 
1146 
1147 #ifdef FEAT_FOLDING
1148 /*
1149  * Evaluate 'foldexpr'.  Returns the foldlevel, and any character preceding
1150  * it in "*cp".  Doesn't give error messages.
1151  */
1152     int
1153 eval_foldexpr(char_u *arg, int *cp)
1154 {
1155     typval_T	tv;
1156     varnumber_T	retval;
1157     char_u	*s;
1158     int		use_sandbox = was_set_insecurely((char_u *)"foldexpr",
1159 								   OPT_LOCAL);
1160 
1161     ++emsg_off;
1162     if (use_sandbox)
1163 	++sandbox;
1164     ++textlock;
1165     *cp = NUL;
1166     if (eval0(arg, &tv, NULL, TRUE) == FAIL)
1167 	retval = 0;
1168     else
1169     {
1170 	/* If the result is a number, just return the number. */
1171 	if (tv.v_type == VAR_NUMBER)
1172 	    retval = tv.vval.v_number;
1173 	else if (tv.v_type != VAR_STRING || tv.vval.v_string == NULL)
1174 	    retval = 0;
1175 	else
1176 	{
1177 	    /* If the result is a string, check if there is a non-digit before
1178 	     * the number. */
1179 	    s = tv.vval.v_string;
1180 	    if (!VIM_ISDIGIT(*s) && *s != '-')
1181 		*cp = *s++;
1182 	    retval = atol((char *)s);
1183 	}
1184 	clear_tv(&tv);
1185     }
1186     --emsg_off;
1187     if (use_sandbox)
1188 	--sandbox;
1189     --textlock;
1190 
1191     return (int)retval;
1192 }
1193 #endif
1194 
1195 /*
1196  * ":let"			list all variable values
1197  * ":let var1 var2"		list variable values
1198  * ":let var = expr"		assignment command.
1199  * ":let var += expr"		assignment command.
1200  * ":let var -= expr"		assignment command.
1201  * ":let var .= expr"		assignment command.
1202  * ":let [var1, var2] = expr"	unpack list.
1203  */
1204     void
1205 ex_let(exarg_T *eap)
1206 {
1207     char_u	*arg = eap->arg;
1208     char_u	*expr = NULL;
1209     typval_T	rettv;
1210     int		i;
1211     int		var_count = 0;
1212     int		semicolon = 0;
1213     char_u	op[2];
1214     char_u	*argend;
1215     int		first = TRUE;
1216 
1217     argend = skip_var_list(arg, &var_count, &semicolon);
1218     if (argend == NULL)
1219 	return;
1220     if (argend > arg && argend[-1] == '.')  /* for var.='str' */
1221 	--argend;
1222     expr = skipwhite(argend);
1223     if (*expr != '=' && !(vim_strchr((char_u *)"+-.", *expr) != NULL
1224 			  && expr[1] == '='))
1225     {
1226 	/*
1227 	 * ":let" without "=": list variables
1228 	 */
1229 	if (*arg == '[')
1230 	    emsg(_(e_invarg));
1231 	else if (!ends_excmd(*arg))
1232 	    /* ":let var1 var2" */
1233 	    arg = list_arg_vars(eap, arg, &first);
1234 	else if (!eap->skip)
1235 	{
1236 	    /* ":let" */
1237 	    list_glob_vars(&first);
1238 	    list_buf_vars(&first);
1239 	    list_win_vars(&first);
1240 	    list_tab_vars(&first);
1241 	    list_script_vars(&first);
1242 	    list_func_vars(&first);
1243 	    list_vim_vars(&first);
1244 	}
1245 	eap->nextcmd = check_nextcmd(arg);
1246     }
1247     else
1248     {
1249 	op[0] = '=';
1250 	op[1] = NUL;
1251 	if (*expr != '=')
1252 	{
1253 	    if (vim_strchr((char_u *)"+-.", *expr) != NULL)
1254 		op[0] = *expr;   /* +=, -= or .= */
1255 	    expr = skipwhite(expr + 2);
1256 	}
1257 	else
1258 	    expr = skipwhite(expr + 1);
1259 
1260 	if (eap->skip)
1261 	    ++emsg_skip;
1262 	i = eval0(expr, &rettv, &eap->nextcmd, !eap->skip);
1263 	if (eap->skip)
1264 	{
1265 	    if (i != FAIL)
1266 		clear_tv(&rettv);
1267 	    --emsg_skip;
1268 	}
1269 	else if (i != FAIL)
1270 	{
1271 	    (void)ex_let_vars(eap->arg, &rettv, FALSE, semicolon, var_count,
1272 									  op);
1273 	    clear_tv(&rettv);
1274 	}
1275     }
1276 }
1277 
1278 /*
1279  * Assign the typevalue "tv" to the variable or variables at "arg_start".
1280  * Handles both "var" with any type and "[var, var; var]" with a list type.
1281  * When "nextchars" is not NULL it points to a string with characters that
1282  * must appear after the variable(s).  Use "+", "-" or "." for add, subtract
1283  * or concatenate.
1284  * Returns OK or FAIL;
1285  */
1286     static int
1287 ex_let_vars(
1288     char_u	*arg_start,
1289     typval_T	*tv,
1290     int		copy,		/* copy values from "tv", don't move */
1291     int		semicolon,	/* from skip_var_list() */
1292     int		var_count,	/* from skip_var_list() */
1293     char_u	*nextchars)
1294 {
1295     char_u	*arg = arg_start;
1296     list_T	*l;
1297     int		i;
1298     listitem_T	*item;
1299     typval_T	ltv;
1300 
1301     if (*arg != '[')
1302     {
1303 	/*
1304 	 * ":let var = expr" or ":for var in list"
1305 	 */
1306 	if (ex_let_one(arg, tv, copy, nextchars, nextchars) == NULL)
1307 	    return FAIL;
1308 	return OK;
1309     }
1310 
1311     /*
1312      * ":let [v1, v2] = list" or ":for [v1, v2] in listlist"
1313      */
1314     if (tv->v_type != VAR_LIST || (l = tv->vval.v_list) == NULL)
1315     {
1316 	emsg(_(e_listreq));
1317 	return FAIL;
1318     }
1319 
1320     i = list_len(l);
1321     if (semicolon == 0 && var_count < i)
1322     {
1323 	emsg(_("E687: Less targets than List items"));
1324 	return FAIL;
1325     }
1326     if (var_count - semicolon > i)
1327     {
1328 	emsg(_("E688: More targets than List items"));
1329 	return FAIL;
1330     }
1331 
1332     item = l->lv_first;
1333     while (*arg != ']')
1334     {
1335 	arg = skipwhite(arg + 1);
1336 	arg = ex_let_one(arg, &item->li_tv, TRUE, (char_u *)",;]", nextchars);
1337 	item = item->li_next;
1338 	if (arg == NULL)
1339 	    return FAIL;
1340 
1341 	arg = skipwhite(arg);
1342 	if (*arg == ';')
1343 	{
1344 	    /* Put the rest of the list (may be empty) in the var after ';'.
1345 	     * Create a new list for this. */
1346 	    l = list_alloc();
1347 	    if (l == NULL)
1348 		return FAIL;
1349 	    while (item != NULL)
1350 	    {
1351 		list_append_tv(l, &item->li_tv);
1352 		item = item->li_next;
1353 	    }
1354 
1355 	    ltv.v_type = VAR_LIST;
1356 	    ltv.v_lock = 0;
1357 	    ltv.vval.v_list = l;
1358 	    l->lv_refcount = 1;
1359 
1360 	    arg = ex_let_one(skipwhite(arg + 1), &ltv, FALSE,
1361 						    (char_u *)"]", nextchars);
1362 	    clear_tv(&ltv);
1363 	    if (arg == NULL)
1364 		return FAIL;
1365 	    break;
1366 	}
1367 	else if (*arg != ',' && *arg != ']')
1368 	{
1369 	    internal_error("ex_let_vars()");
1370 	    return FAIL;
1371 	}
1372     }
1373 
1374     return OK;
1375 }
1376 
1377 /*
1378  * Skip over assignable variable "var" or list of variables "[var, var]".
1379  * Used for ":let varvar = expr" and ":for varvar in expr".
1380  * For "[var, var]" increment "*var_count" for each variable.
1381  * for "[var, var; var]" set "semicolon".
1382  * Return NULL for an error.
1383  */
1384     static char_u *
1385 skip_var_list(
1386     char_u	*arg,
1387     int		*var_count,
1388     int		*semicolon)
1389 {
1390     char_u	*p, *s;
1391 
1392     if (*arg == '[')
1393     {
1394 	/* "[var, var]": find the matching ']'. */
1395 	p = arg;
1396 	for (;;)
1397 	{
1398 	    p = skipwhite(p + 1);	/* skip whites after '[', ';' or ',' */
1399 	    s = skip_var_one(p);
1400 	    if (s == p)
1401 	    {
1402 		semsg(_(e_invarg2), p);
1403 		return NULL;
1404 	    }
1405 	    ++*var_count;
1406 
1407 	    p = skipwhite(s);
1408 	    if (*p == ']')
1409 		break;
1410 	    else if (*p == ';')
1411 	    {
1412 		if (*semicolon == 1)
1413 		{
1414 		    emsg(_("Double ; in list of variables"));
1415 		    return NULL;
1416 		}
1417 		*semicolon = 1;
1418 	    }
1419 	    else if (*p != ',')
1420 	    {
1421 		semsg(_(e_invarg2), p);
1422 		return NULL;
1423 	    }
1424 	}
1425 	return p + 1;
1426     }
1427     else
1428 	return skip_var_one(arg);
1429 }
1430 
1431 /*
1432  * Skip one (assignable) variable name, including @r, $VAR, &option, d.key,
1433  * l[idx].
1434  */
1435     static char_u *
1436 skip_var_one(char_u *arg)
1437 {
1438     if (*arg == '@' && arg[1] != NUL)
1439 	return arg + 2;
1440     return find_name_end(*arg == '$' || *arg == '&' ? arg + 1 : arg,
1441 				   NULL, NULL, FNE_INCL_BR | FNE_CHECK_START);
1442 }
1443 
1444 /*
1445  * List variables for hashtab "ht" with prefix "prefix".
1446  * If "empty" is TRUE also list NULL strings as empty strings.
1447  */
1448     void
1449 list_hashtable_vars(
1450     hashtab_T	*ht,
1451     char_u	*prefix,
1452     int		empty,
1453     int		*first)
1454 {
1455     hashitem_T	*hi;
1456     dictitem_T	*di;
1457     int		todo;
1458     char_u	buf[IOSIZE];
1459 
1460     todo = (int)ht->ht_used;
1461     for (hi = ht->ht_array; todo > 0 && !got_int; ++hi)
1462     {
1463 	if (!HASHITEM_EMPTY(hi))
1464 	{
1465 	    --todo;
1466 	    di = HI2DI(hi);
1467 
1468 	    // apply :filter /pat/ to variable name
1469 	    vim_strncpy((char_u *) buf, prefix, IOSIZE - 1);
1470 	    vim_strcat((char_u *) buf, di->di_key, IOSIZE);
1471 	    if (message_filtered(buf))
1472 		continue;
1473 
1474 	    if (empty || di->di_tv.v_type != VAR_STRING
1475 					   || di->di_tv.vval.v_string != NULL)
1476 		list_one_var(di, prefix, first);
1477 	}
1478     }
1479 }
1480 
1481 /*
1482  * List global variables.
1483  */
1484     static void
1485 list_glob_vars(int *first)
1486 {
1487     list_hashtable_vars(&globvarht, (char_u *)"", TRUE, first);
1488 }
1489 
1490 /*
1491  * List buffer variables.
1492  */
1493     static void
1494 list_buf_vars(int *first)
1495 {
1496     list_hashtable_vars(&curbuf->b_vars->dv_hashtab, (char_u *)"b:",
1497 								 TRUE, first);
1498 }
1499 
1500 /*
1501  * List window variables.
1502  */
1503     static void
1504 list_win_vars(int *first)
1505 {
1506     list_hashtable_vars(&curwin->w_vars->dv_hashtab,
1507 						 (char_u *)"w:", TRUE, first);
1508 }
1509 
1510 /*
1511  * List tab page variables.
1512  */
1513     static void
1514 list_tab_vars(int *first)
1515 {
1516     list_hashtable_vars(&curtab->tp_vars->dv_hashtab,
1517 						 (char_u *)"t:", TRUE, first);
1518 }
1519 
1520 /*
1521  * List Vim variables.
1522  */
1523     static void
1524 list_vim_vars(int *first)
1525 {
1526     list_hashtable_vars(&vimvarht, (char_u *)"v:", FALSE, first);
1527 }
1528 
1529 /*
1530  * List script-local variables, if there is a script.
1531  */
1532     static void
1533 list_script_vars(int *first)
1534 {
1535     if (current_sctx.sc_sid > 0 && current_sctx.sc_sid <= ga_scripts.ga_len)
1536 	list_hashtable_vars(&SCRIPT_VARS(current_sctx.sc_sid),
1537 						(char_u *)"s:", FALSE, first);
1538 }
1539 
1540 /*
1541  * List variables in "arg".
1542  */
1543     static char_u *
1544 list_arg_vars(exarg_T *eap, char_u *arg, int *first)
1545 {
1546     int		error = FALSE;
1547     int		len;
1548     char_u	*name;
1549     char_u	*name_start;
1550     char_u	*arg_subsc;
1551     char_u	*tofree;
1552     typval_T    tv;
1553 
1554     while (!ends_excmd(*arg) && !got_int)
1555     {
1556 	if (error || eap->skip)
1557 	{
1558 	    arg = find_name_end(arg, NULL, NULL, FNE_INCL_BR | FNE_CHECK_START);
1559 	    if (!VIM_ISWHITE(*arg) && !ends_excmd(*arg))
1560 	    {
1561 		emsg_severe = TRUE;
1562 		emsg(_(e_trailing));
1563 		break;
1564 	    }
1565 	}
1566 	else
1567 	{
1568 	    /* get_name_len() takes care of expanding curly braces */
1569 	    name_start = name = arg;
1570 	    len = get_name_len(&arg, &tofree, TRUE, TRUE);
1571 	    if (len <= 0)
1572 	    {
1573 		/* This is mainly to keep test 49 working: when expanding
1574 		 * curly braces fails overrule the exception error message. */
1575 		if (len < 0 && !aborting())
1576 		{
1577 		    emsg_severe = TRUE;
1578 		    semsg(_(e_invarg2), arg);
1579 		    break;
1580 		}
1581 		error = TRUE;
1582 	    }
1583 	    else
1584 	    {
1585 		if (tofree != NULL)
1586 		    name = tofree;
1587 		if (get_var_tv(name, len, &tv, NULL, TRUE, FALSE) == FAIL)
1588 		    error = TRUE;
1589 		else
1590 		{
1591 		    /* handle d.key, l[idx], f(expr) */
1592 		    arg_subsc = arg;
1593 		    if (handle_subscript(&arg, &tv, TRUE, TRUE) == FAIL)
1594 			error = TRUE;
1595 		    else
1596 		    {
1597 			if (arg == arg_subsc && len == 2 && name[1] == ':')
1598 			{
1599 			    switch (*name)
1600 			    {
1601 				case 'g': list_glob_vars(first); break;
1602 				case 'b': list_buf_vars(first); break;
1603 				case 'w': list_win_vars(first); break;
1604 				case 't': list_tab_vars(first); break;
1605 				case 'v': list_vim_vars(first); break;
1606 				case 's': list_script_vars(first); break;
1607 				case 'l': list_func_vars(first); break;
1608 				default:
1609 					  semsg(_("E738: Can't list variables for %s"), name);
1610 			    }
1611 			}
1612 			else
1613 			{
1614 			    char_u	numbuf[NUMBUFLEN];
1615 			    char_u	*tf;
1616 			    int		c;
1617 			    char_u	*s;
1618 
1619 			    s = echo_string(&tv, &tf, numbuf, 0);
1620 			    c = *arg;
1621 			    *arg = NUL;
1622 			    list_one_var_a((char_u *)"",
1623 				    arg == arg_subsc ? name : name_start,
1624 				    tv.v_type,
1625 				    s == NULL ? (char_u *)"" : s,
1626 				    first);
1627 			    *arg = c;
1628 			    vim_free(tf);
1629 			}
1630 			clear_tv(&tv);
1631 		    }
1632 		}
1633 	    }
1634 
1635 	    vim_free(tofree);
1636 	}
1637 
1638 	arg = skipwhite(arg);
1639     }
1640 
1641     return arg;
1642 }
1643 
1644 /*
1645  * Set one item of ":let var = expr" or ":let [v1, v2] = list" to its value.
1646  * Returns a pointer to the char just after the var name.
1647  * Returns NULL if there is an error.
1648  */
1649     static char_u *
1650 ex_let_one(
1651     char_u	*arg,		/* points to variable name */
1652     typval_T	*tv,		/* value to assign to variable */
1653     int		copy,		/* copy value from "tv" */
1654     char_u	*endchars,	/* valid chars after variable name  or NULL */
1655     char_u	*op)		/* "+", "-", "."  or NULL*/
1656 {
1657     int		c1;
1658     char_u	*name;
1659     char_u	*p;
1660     char_u	*arg_end = NULL;
1661     int		len;
1662     int		opt_flags;
1663     char_u	*tofree = NULL;
1664 
1665     /*
1666      * ":let $VAR = expr": Set environment variable.
1667      */
1668     if (*arg == '$')
1669     {
1670 	/* Find the end of the name. */
1671 	++arg;
1672 	name = arg;
1673 	len = get_env_len(&arg);
1674 	if (len == 0)
1675 	    semsg(_(e_invarg2), name - 1);
1676 	else
1677 	{
1678 	    if (op != NULL && (*op == '+' || *op == '-'))
1679 		semsg(_(e_letwrong), op);
1680 	    else if (endchars != NULL
1681 			     && vim_strchr(endchars, *skipwhite(arg)) == NULL)
1682 		emsg(_(e_letunexp));
1683 	    else if (!check_secure())
1684 	    {
1685 		c1 = name[len];
1686 		name[len] = NUL;
1687 		p = tv_get_string_chk(tv);
1688 		if (p != NULL && op != NULL && *op == '.')
1689 		{
1690 		    int	    mustfree = FALSE;
1691 		    char_u  *s = vim_getenv(name, &mustfree);
1692 
1693 		    if (s != NULL)
1694 		    {
1695 			p = tofree = concat_str(s, p);
1696 			if (mustfree)
1697 			    vim_free(s);
1698 		    }
1699 		}
1700 		if (p != NULL)
1701 		{
1702 		    vim_setenv(name, p);
1703 		    if (STRICMP(name, "HOME") == 0)
1704 			init_homedir();
1705 		    else if (didset_vim && STRICMP(name, "VIM") == 0)
1706 			didset_vim = FALSE;
1707 		    else if (didset_vimruntime
1708 					&& STRICMP(name, "VIMRUNTIME") == 0)
1709 			didset_vimruntime = FALSE;
1710 		    arg_end = arg;
1711 		}
1712 		name[len] = c1;
1713 		vim_free(tofree);
1714 	    }
1715 	}
1716     }
1717 
1718     /*
1719      * ":let &option = expr": Set option value.
1720      * ":let &l:option = expr": Set local option value.
1721      * ":let &g:option = expr": Set global option value.
1722      */
1723     else if (*arg == '&')
1724     {
1725 	/* Find the end of the name. */
1726 	p = find_option_end(&arg, &opt_flags);
1727 	if (p == NULL || (endchars != NULL
1728 			      && vim_strchr(endchars, *skipwhite(p)) == NULL))
1729 	    emsg(_(e_letunexp));
1730 	else
1731 	{
1732 	    long	n;
1733 	    int		opt_type;
1734 	    long	numval;
1735 	    char_u	*stringval = NULL;
1736 	    char_u	*s;
1737 
1738 	    c1 = *p;
1739 	    *p = NUL;
1740 
1741 	    n = (long)tv_get_number(tv);
1742 	    s = tv_get_string_chk(tv);	    /* != NULL if number or string */
1743 	    if (s != NULL && op != NULL && *op != '=')
1744 	    {
1745 		opt_type = get_option_value(arg, &numval,
1746 						       &stringval, opt_flags);
1747 		if ((opt_type == 1 && *op == '.')
1748 			|| (opt_type == 0 && *op != '.'))
1749 		{
1750 		    semsg(_(e_letwrong), op);
1751 		    s = NULL;  /* don't set the value */
1752 		}
1753 		else
1754 		{
1755 		    if (opt_type == 1)  /* number */
1756 		    {
1757 			if (*op == '+')
1758 			    n = numval + n;
1759 			else
1760 			    n = numval - n;
1761 		    }
1762 		    else if (opt_type == 0 && stringval != NULL) /* string */
1763 		    {
1764 			s = concat_str(stringval, s);
1765 			vim_free(stringval);
1766 			stringval = s;
1767 		    }
1768 		}
1769 	    }
1770 	    if (s != NULL)
1771 	    {
1772 		set_option_value(arg, n, s, opt_flags);
1773 		arg_end = p;
1774 	    }
1775 	    *p = c1;
1776 	    vim_free(stringval);
1777 	}
1778     }
1779 
1780     /*
1781      * ":let @r = expr": Set register contents.
1782      */
1783     else if (*arg == '@')
1784     {
1785 	++arg;
1786 	if (op != NULL && (*op == '+' || *op == '-'))
1787 	    semsg(_(e_letwrong), op);
1788 	else if (endchars != NULL
1789 			 && vim_strchr(endchars, *skipwhite(arg + 1)) == NULL)
1790 	    emsg(_(e_letunexp));
1791 	else
1792 	{
1793 	    char_u	*ptofree = NULL;
1794 	    char_u	*s;
1795 
1796 	    p = tv_get_string_chk(tv);
1797 	    if (p != NULL && op != NULL && *op == '.')
1798 	    {
1799 		s = get_reg_contents(*arg == '@' ? '"' : *arg, GREG_EXPR_SRC);
1800 		if (s != NULL)
1801 		{
1802 		    p = ptofree = concat_str(s, p);
1803 		    vim_free(s);
1804 		}
1805 	    }
1806 	    if (p != NULL)
1807 	    {
1808 		write_reg_contents(*arg == '@' ? '"' : *arg, p, -1, FALSE);
1809 		arg_end = arg + 1;
1810 	    }
1811 	    vim_free(ptofree);
1812 	}
1813     }
1814 
1815     /*
1816      * ":let var = expr": Set internal variable.
1817      * ":let {expr} = expr": Idem, name made with curly braces
1818      */
1819     else if (eval_isnamec1(*arg) || *arg == '{')
1820     {
1821 	lval_T	lv;
1822 
1823 	p = get_lval(arg, tv, &lv, FALSE, FALSE, 0, FNE_CHECK_START);
1824 	if (p != NULL && lv.ll_name != NULL)
1825 	{
1826 	    if (endchars != NULL && vim_strchr(endchars, *skipwhite(p)) == NULL)
1827 		emsg(_(e_letunexp));
1828 	    else
1829 	    {
1830 		set_var_lval(&lv, p, tv, copy, op);
1831 		arg_end = p;
1832 	    }
1833 	}
1834 	clear_lval(&lv);
1835     }
1836 
1837     else
1838 	semsg(_(e_invarg2), arg);
1839 
1840     return arg_end;
1841 }
1842 
1843 /*
1844  * Get an lval: variable, Dict item or List item that can be assigned a value
1845  * to: "name", "na{me}", "name[expr]", "name[expr:expr]", "name[expr][expr]",
1846  * "name.key", "name.key[expr]" etc.
1847  * Indexing only works if "name" is an existing List or Dictionary.
1848  * "name" points to the start of the name.
1849  * If "rettv" is not NULL it points to the value to be assigned.
1850  * "unlet" is TRUE for ":unlet": slightly different behavior when something is
1851  * wrong; must end in space or cmd separator.
1852  *
1853  * flags:
1854  *  GLV_QUIET:       do not give error messages
1855  *  GLV_READ_ONLY:   will not change the variable
1856  *  GLV_NO_AUTOLOAD: do not use script autoloading
1857  *
1858  * Returns a pointer to just after the name, including indexes.
1859  * When an evaluation error occurs "lp->ll_name" is NULL;
1860  * Returns NULL for a parsing error.  Still need to free items in "lp"!
1861  */
1862     char_u *
1863 get_lval(
1864     char_u	*name,
1865     typval_T	*rettv,
1866     lval_T	*lp,
1867     int		unlet,
1868     int		skip,
1869     int		flags,	    /* GLV_ values */
1870     int		fne_flags)  /* flags for find_name_end() */
1871 {
1872     char_u	*p;
1873     char_u	*expr_start, *expr_end;
1874     int		cc;
1875     dictitem_T	*v;
1876     typval_T	var1;
1877     typval_T	var2;
1878     int		empty1 = FALSE;
1879     listitem_T	*ni;
1880     char_u	*key = NULL;
1881     int		len;
1882     hashtab_T	*ht;
1883     int		quiet = flags & GLV_QUIET;
1884 
1885     /* Clear everything in "lp". */
1886     vim_memset(lp, 0, sizeof(lval_T));
1887 
1888     if (skip)
1889     {
1890 	/* When skipping just find the end of the name. */
1891 	lp->ll_name = name;
1892 	return find_name_end(name, NULL, NULL, FNE_INCL_BR | fne_flags);
1893     }
1894 
1895     /* Find the end of the name. */
1896     p = find_name_end(name, &expr_start, &expr_end, fne_flags);
1897     if (expr_start != NULL)
1898     {
1899 	/* Don't expand the name when we already know there is an error. */
1900 	if (unlet && !VIM_ISWHITE(*p) && !ends_excmd(*p)
1901 						    && *p != '[' && *p != '.')
1902 	{
1903 	    emsg(_(e_trailing));
1904 	    return NULL;
1905 	}
1906 
1907 	lp->ll_exp_name = make_expanded_name(name, expr_start, expr_end, p);
1908 	if (lp->ll_exp_name == NULL)
1909 	{
1910 	    /* Report an invalid expression in braces, unless the
1911 	     * expression evaluation has been cancelled due to an
1912 	     * aborting error, an interrupt, or an exception. */
1913 	    if (!aborting() && !quiet)
1914 	    {
1915 		emsg_severe = TRUE;
1916 		semsg(_(e_invarg2), name);
1917 		return NULL;
1918 	    }
1919 	}
1920 	lp->ll_name = lp->ll_exp_name;
1921     }
1922     else
1923 	lp->ll_name = name;
1924 
1925     /* Without [idx] or .key we are done. */
1926     if ((*p != '[' && *p != '.') || lp->ll_name == NULL)
1927 	return p;
1928 
1929     cc = *p;
1930     *p = NUL;
1931     /* Only pass &ht when we would write to the variable, it prevents autoload
1932      * as well. */
1933     v = find_var(lp->ll_name, (flags & GLV_READ_ONLY) ? NULL : &ht,
1934 						      flags & GLV_NO_AUTOLOAD);
1935     if (v == NULL && !quiet)
1936 	semsg(_(e_undefvar), lp->ll_name);
1937     *p = cc;
1938     if (v == NULL)
1939 	return NULL;
1940 
1941     /*
1942      * Loop until no more [idx] or .key is following.
1943      */
1944     lp->ll_tv = &v->di_tv;
1945     var1.v_type = VAR_UNKNOWN;
1946     var2.v_type = VAR_UNKNOWN;
1947     while (*p == '[' || (*p == '.' && lp->ll_tv->v_type == VAR_DICT))
1948     {
1949 	if (!(lp->ll_tv->v_type == VAR_LIST && lp->ll_tv->vval.v_list != NULL)
1950 		&& !(lp->ll_tv->v_type == VAR_DICT
1951 					   && lp->ll_tv->vval.v_dict != NULL)
1952 		&& !(lp->ll_tv->v_type == VAR_BLOB
1953 					   && lp->ll_tv->vval.v_blob != NULL))
1954 	{
1955 	    if (!quiet)
1956 		emsg(_("E689: Can only index a List, Dictionary or Blob"));
1957 	    return NULL;
1958 	}
1959 	if (lp->ll_range)
1960 	{
1961 	    if (!quiet)
1962 		emsg(_("E708: [:] must come last"));
1963 	    return NULL;
1964 	}
1965 
1966 	len = -1;
1967 	if (*p == '.')
1968 	{
1969 	    key = p + 1;
1970 	    for (len = 0; ASCII_ISALNUM(key[len]) || key[len] == '_'; ++len)
1971 		;
1972 	    if (len == 0)
1973 	    {
1974 		if (!quiet)
1975 		    emsg(_(e_emptykey));
1976 		return NULL;
1977 	    }
1978 	    p = key + len;
1979 	}
1980 	else
1981 	{
1982 	    /* Get the index [expr] or the first index [expr: ]. */
1983 	    p = skipwhite(p + 1);
1984 	    if (*p == ':')
1985 		empty1 = TRUE;
1986 	    else
1987 	    {
1988 		empty1 = FALSE;
1989 		if (eval1(&p, &var1, TRUE) == FAIL)	/* recursive! */
1990 		    return NULL;
1991 		if (tv_get_string_chk(&var1) == NULL)
1992 		{
1993 		    /* not a number or string */
1994 		    clear_tv(&var1);
1995 		    return NULL;
1996 		}
1997 	    }
1998 
1999 	    /* Optionally get the second index [ :expr]. */
2000 	    if (*p == ':')
2001 	    {
2002 		if (lp->ll_tv->v_type == VAR_DICT)
2003 		{
2004 		    if (!quiet)
2005 			emsg(_(e_dictrange));
2006 		    clear_tv(&var1);
2007 		    return NULL;
2008 		}
2009 		if (rettv != NULL
2010 			&& !(rettv->v_type == VAR_LIST
2011 						 && rettv->vval.v_list != NULL)
2012 			&& !(rettv->v_type == VAR_BLOB
2013 						&& rettv->vval.v_blob != NULL))
2014 		{
2015 		    if (!quiet)
2016 			emsg(_("E709: [:] requires a List or Blob value"));
2017 		    clear_tv(&var1);
2018 		    return NULL;
2019 		}
2020 		p = skipwhite(p + 1);
2021 		if (*p == ']')
2022 		    lp->ll_empty2 = TRUE;
2023 		else
2024 		{
2025 		    lp->ll_empty2 = FALSE;
2026 		    if (eval1(&p, &var2, TRUE) == FAIL)	/* recursive! */
2027 		    {
2028 			clear_tv(&var1);
2029 			return NULL;
2030 		    }
2031 		    if (tv_get_string_chk(&var2) == NULL)
2032 		    {
2033 			/* not a number or string */
2034 			clear_tv(&var1);
2035 			clear_tv(&var2);
2036 			return NULL;
2037 		    }
2038 		}
2039 		lp->ll_range = TRUE;
2040 	    }
2041 	    else
2042 		lp->ll_range = FALSE;
2043 
2044 	    if (*p != ']')
2045 	    {
2046 		if (!quiet)
2047 		    emsg(_(e_missbrac));
2048 		clear_tv(&var1);
2049 		clear_tv(&var2);
2050 		return NULL;
2051 	    }
2052 
2053 	    /* Skip to past ']'. */
2054 	    ++p;
2055 	}
2056 
2057 	if (lp->ll_tv->v_type == VAR_DICT)
2058 	{
2059 	    if (len == -1)
2060 	    {
2061 		/* "[key]": get key from "var1" */
2062 		key = tv_get_string_chk(&var1);	/* is number or string */
2063 		if (key == NULL)
2064 		{
2065 		    clear_tv(&var1);
2066 		    return NULL;
2067 		}
2068 	    }
2069 	    lp->ll_list = NULL;
2070 	    lp->ll_dict = lp->ll_tv->vval.v_dict;
2071 	    lp->ll_di = dict_find(lp->ll_dict, key, len);
2072 
2073 	    /* When assigning to a scope dictionary check that a function and
2074 	     * variable name is valid (only variable name unless it is l: or
2075 	     * g: dictionary). Disallow overwriting a builtin function. */
2076 	    if (rettv != NULL && lp->ll_dict->dv_scope != 0)
2077 	    {
2078 		int prevval;
2079 		int wrong;
2080 
2081 		if (len != -1)
2082 		{
2083 		    prevval = key[len];
2084 		    key[len] = NUL;
2085 		}
2086 		else
2087 		    prevval = 0; /* avoid compiler warning */
2088 		wrong = (lp->ll_dict->dv_scope == VAR_DEF_SCOPE
2089 			       && rettv->v_type == VAR_FUNC
2090 			       && var_check_func_name(key, lp->ll_di == NULL))
2091 			|| !valid_varname(key);
2092 		if (len != -1)
2093 		    key[len] = prevval;
2094 		if (wrong)
2095 		    return NULL;
2096 	    }
2097 
2098 	    if (lp->ll_di == NULL)
2099 	    {
2100 		/* Can't add "v:" variable. */
2101 		if (lp->ll_dict == &vimvardict)
2102 		{
2103 		    semsg(_(e_illvar), name);
2104 		    return NULL;
2105 		}
2106 
2107 		/* Key does not exist in dict: may need to add it. */
2108 		if (*p == '[' || *p == '.' || unlet)
2109 		{
2110 		    if (!quiet)
2111 			semsg(_(e_dictkey), key);
2112 		    clear_tv(&var1);
2113 		    return NULL;
2114 		}
2115 		if (len == -1)
2116 		    lp->ll_newkey = vim_strsave(key);
2117 		else
2118 		    lp->ll_newkey = vim_strnsave(key, len);
2119 		clear_tv(&var1);
2120 		if (lp->ll_newkey == NULL)
2121 		    p = NULL;
2122 		break;
2123 	    }
2124 	    /* existing variable, need to check if it can be changed */
2125 	    else if ((flags & GLV_READ_ONLY) == 0
2126 			     && var_check_ro(lp->ll_di->di_flags, name, FALSE))
2127 	    {
2128 		clear_tv(&var1);
2129 		return NULL;
2130 	    }
2131 
2132 	    clear_tv(&var1);
2133 	    lp->ll_tv = &lp->ll_di->di_tv;
2134 	}
2135 	else if (lp->ll_tv->v_type == VAR_BLOB)
2136 	{
2137 	    long bloblen = blob_len(lp->ll_tv->vval.v_blob);
2138 
2139 	    /*
2140 	     * Get the number and item for the only or first index of the List.
2141 	     */
2142 	    if (empty1)
2143 		lp->ll_n1 = 0;
2144 	    else
2145 		// is number or string
2146 		lp->ll_n1 = (long)tv_get_number(&var1);
2147 	    clear_tv(&var1);
2148 
2149 	    if (lp->ll_n1 < 0
2150 		    || lp->ll_n1 > bloblen
2151 		    || (lp->ll_range && lp->ll_n1 == bloblen))
2152 	    {
2153 		if (!quiet)
2154 		    semsg(_(e_blobidx), lp->ll_n1);
2155 		clear_tv(&var2);
2156 		return NULL;
2157 	    }
2158 	    if (lp->ll_range && !lp->ll_empty2)
2159 	    {
2160 		lp->ll_n2 = (long)tv_get_number(&var2);
2161 		clear_tv(&var2);
2162 		if (lp->ll_n2 < 0
2163 			|| lp->ll_n2 >= bloblen
2164 			|| lp->ll_n2 < lp->ll_n1)
2165 		{
2166 		    if (!quiet)
2167 			semsg(_(e_blobidx), lp->ll_n2);
2168 		    return NULL;
2169 		}
2170 	    }
2171 	    lp->ll_blob = lp->ll_tv->vval.v_blob;
2172 	    lp->ll_tv = NULL;
2173 	}
2174 	else
2175 	{
2176 	    /*
2177 	     * Get the number and item for the only or first index of the List.
2178 	     */
2179 	    if (empty1)
2180 		lp->ll_n1 = 0;
2181 	    else
2182 		/* is number or string */
2183 		lp->ll_n1 = (long)tv_get_number(&var1);
2184 	    clear_tv(&var1);
2185 
2186 	    lp->ll_dict = NULL;
2187 	    lp->ll_list = lp->ll_tv->vval.v_list;
2188 	    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
2189 	    if (lp->ll_li == NULL)
2190 	    {
2191 		if (lp->ll_n1 < 0)
2192 		{
2193 		    lp->ll_n1 = 0;
2194 		    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
2195 		}
2196 	    }
2197 	    if (lp->ll_li == NULL)
2198 	    {
2199 		clear_tv(&var2);
2200 		if (!quiet)
2201 		    semsg(_(e_listidx), lp->ll_n1);
2202 		return NULL;
2203 	    }
2204 
2205 	    /*
2206 	     * May need to find the item or absolute index for the second
2207 	     * index of a range.
2208 	     * When no index given: "lp->ll_empty2" is TRUE.
2209 	     * Otherwise "lp->ll_n2" is set to the second index.
2210 	     */
2211 	    if (lp->ll_range && !lp->ll_empty2)
2212 	    {
2213 		lp->ll_n2 = (long)tv_get_number(&var2);
2214 						    /* is number or string */
2215 		clear_tv(&var2);
2216 		if (lp->ll_n2 < 0)
2217 		{
2218 		    ni = list_find(lp->ll_list, lp->ll_n2);
2219 		    if (ni == NULL)
2220 		    {
2221 			if (!quiet)
2222 			    semsg(_(e_listidx), lp->ll_n2);
2223 			return NULL;
2224 		    }
2225 		    lp->ll_n2 = list_idx_of_item(lp->ll_list, ni);
2226 		}
2227 
2228 		/* Check that lp->ll_n2 isn't before lp->ll_n1. */
2229 		if (lp->ll_n1 < 0)
2230 		    lp->ll_n1 = list_idx_of_item(lp->ll_list, lp->ll_li);
2231 		if (lp->ll_n2 < lp->ll_n1)
2232 		{
2233 		    if (!quiet)
2234 			semsg(_(e_listidx), lp->ll_n2);
2235 		    return NULL;
2236 		}
2237 	    }
2238 
2239 	    lp->ll_tv = &lp->ll_li->li_tv;
2240 	}
2241     }
2242 
2243     clear_tv(&var1);
2244     return p;
2245 }
2246 
2247 /*
2248  * Clear lval "lp" that was filled by get_lval().
2249  */
2250     void
2251 clear_lval(lval_T *lp)
2252 {
2253     vim_free(lp->ll_exp_name);
2254     vim_free(lp->ll_newkey);
2255 }
2256 
2257 /*
2258  * Set a variable that was parsed by get_lval() to "rettv".
2259  * "endp" points to just after the parsed name.
2260  * "op" is NULL, "+" for "+=", "-" for "-=", "." for ".=" or "=" for "=".
2261  */
2262     static void
2263 set_var_lval(
2264     lval_T	*lp,
2265     char_u	*endp,
2266     typval_T	*rettv,
2267     int		copy,
2268     char_u	*op)
2269 {
2270     int		cc;
2271     listitem_T	*ri;
2272     dictitem_T	*di;
2273 
2274     if (lp->ll_tv == NULL)
2275     {
2276 	cc = *endp;
2277 	*endp = NUL;
2278 	if (lp->ll_blob != NULL)
2279 	{
2280 	    int	    error = FALSE, val;
2281 
2282 	    if (op != NULL && *op != '=')
2283 	    {
2284 		semsg(_(e_letwrong), op);
2285 		return;
2286 	    }
2287 
2288 	    if (lp->ll_range && rettv->v_type == VAR_BLOB)
2289 	    {
2290 		int	il, ir;
2291 
2292 		if (lp->ll_empty2)
2293 		    lp->ll_n2 = blob_len(lp->ll_blob) - 1;
2294 
2295 		if (lp->ll_n2 - lp->ll_n1 + 1 != blob_len(rettv->vval.v_blob))
2296 		{
2297 		    emsg(_("E972: Blob value does not have the right number of bytes"));
2298 		    return;
2299 		}
2300 		if (lp->ll_empty2)
2301 		    lp->ll_n2 = blob_len(lp->ll_blob);
2302 
2303 		ir = 0;
2304 		for (il = lp->ll_n1; il <= lp->ll_n2; il++)
2305 		    blob_set(lp->ll_blob, il,
2306 			    blob_get(rettv->vval.v_blob, ir++));
2307 	    }
2308 	    else
2309 	    {
2310 		val = (int)tv_get_number_chk(rettv, &error);
2311 		if (!error)
2312 		{
2313 		    garray_T *gap = &lp->ll_blob->bv_ga;
2314 
2315 		    // Allow for appending a byte.  Setting a byte beyond
2316 		    // the end is an error otherwise.
2317 		    if (lp->ll_n1 < gap->ga_len
2318 			    || (lp->ll_n1 == gap->ga_len
2319 				&& ga_grow(&lp->ll_blob->bv_ga, 1) == OK))
2320 		    {
2321 			blob_set(lp->ll_blob, lp->ll_n1, val);
2322 			if (lp->ll_n1 == gap->ga_len)
2323 			    ++gap->ga_len;
2324 		    }
2325 		    // error for invalid range was already given in get_lval()
2326 		}
2327 	    }
2328 	}
2329 	else if (op != NULL && *op != '=')
2330 	{
2331 	    typval_T tv;
2332 
2333 	    /* handle +=, -= and .= */
2334 	    di = NULL;
2335 	    if (get_var_tv(lp->ll_name, (int)STRLEN(lp->ll_name),
2336 					     &tv, &di, TRUE, FALSE) == OK)
2337 	    {
2338 		if ((di == NULL
2339 		       || (!var_check_ro(di->di_flags, lp->ll_name, FALSE)
2340 			  && !tv_check_lock(di->di_tv.v_lock, lp->ll_name,
2341 								  FALSE)))
2342 			&& tv_op(&tv, rettv, op) == OK)
2343 		    set_var(lp->ll_name, &tv, FALSE);
2344 		clear_tv(&tv);
2345 	    }
2346 	}
2347 	else
2348 	    set_var(lp->ll_name, rettv, copy);
2349 	*endp = cc;
2350     }
2351     else if (tv_check_lock(lp->ll_newkey == NULL
2352 		? lp->ll_tv->v_lock
2353 		: lp->ll_tv->vval.v_dict->dv_lock, lp->ll_name, FALSE))
2354 	;
2355     else if (lp->ll_range)
2356     {
2357 	listitem_T *ll_li = lp->ll_li;
2358 	int	    ll_n1 = lp->ll_n1;
2359 
2360 	/*
2361 	 * Check whether any of the list items is locked
2362 	 */
2363 	for (ri = rettv->vval.v_list->lv_first; ri != NULL && ll_li != NULL; )
2364 	{
2365 	    if (tv_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
2366 		return;
2367 	    ri = ri->li_next;
2368 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == ll_n1))
2369 		break;
2370 	    ll_li = ll_li->li_next;
2371 	    ++ll_n1;
2372 	}
2373 
2374 	/*
2375 	 * Assign the List values to the list items.
2376 	 */
2377 	for (ri = rettv->vval.v_list->lv_first; ri != NULL; )
2378 	{
2379 	    if (op != NULL && *op != '=')
2380 		tv_op(&lp->ll_li->li_tv, &ri->li_tv, op);
2381 	    else
2382 	    {
2383 		clear_tv(&lp->ll_li->li_tv);
2384 		copy_tv(&ri->li_tv, &lp->ll_li->li_tv);
2385 	    }
2386 	    ri = ri->li_next;
2387 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == lp->ll_n1))
2388 		break;
2389 	    if (lp->ll_li->li_next == NULL)
2390 	    {
2391 		/* Need to add an empty item. */
2392 		if (list_append_number(lp->ll_list, 0) == FAIL)
2393 		{
2394 		    ri = NULL;
2395 		    break;
2396 		}
2397 	    }
2398 	    lp->ll_li = lp->ll_li->li_next;
2399 	    ++lp->ll_n1;
2400 	}
2401 	if (ri != NULL)
2402 	    emsg(_("E710: List value has more items than target"));
2403 	else if (lp->ll_empty2
2404 		? (lp->ll_li != NULL && lp->ll_li->li_next != NULL)
2405 		: lp->ll_n1 != lp->ll_n2)
2406 	    emsg(_("E711: List value has not enough items"));
2407     }
2408     else
2409     {
2410 	/*
2411 	 * Assign to a List or Dictionary item.
2412 	 */
2413 	if (lp->ll_newkey != NULL)
2414 	{
2415 	    if (op != NULL && *op != '=')
2416 	    {
2417 		semsg(_(e_letwrong), op);
2418 		return;
2419 	    }
2420 
2421 	    /* Need to add an item to the Dictionary. */
2422 	    di = dictitem_alloc(lp->ll_newkey);
2423 	    if (di == NULL)
2424 		return;
2425 	    if (dict_add(lp->ll_tv->vval.v_dict, di) == FAIL)
2426 	    {
2427 		vim_free(di);
2428 		return;
2429 	    }
2430 	    lp->ll_tv = &di->di_tv;
2431 	}
2432 	else if (op != NULL && *op != '=')
2433 	{
2434 	    tv_op(lp->ll_tv, rettv, op);
2435 	    return;
2436 	}
2437 	else
2438 	    clear_tv(lp->ll_tv);
2439 
2440 	/*
2441 	 * Assign the value to the variable or list item.
2442 	 */
2443 	if (copy)
2444 	    copy_tv(rettv, lp->ll_tv);
2445 	else
2446 	{
2447 	    *lp->ll_tv = *rettv;
2448 	    lp->ll_tv->v_lock = 0;
2449 	    init_tv(rettv);
2450 	}
2451     }
2452 }
2453 
2454 /*
2455  * Handle "tv1 += tv2", "tv1 -= tv2" and "tv1 .= tv2"
2456  * Returns OK or FAIL.
2457  */
2458     static int
2459 tv_op(typval_T *tv1, typval_T *tv2, char_u *op)
2460 {
2461     varnumber_T	n;
2462     char_u	numbuf[NUMBUFLEN];
2463     char_u	*s;
2464 
2465     /* Can't do anything with a Funcref, Dict, v:true on the right. */
2466     if (tv2->v_type != VAR_FUNC && tv2->v_type != VAR_DICT
2467 						&& tv2->v_type != VAR_SPECIAL)
2468     {
2469 	switch (tv1->v_type)
2470 	{
2471 	    case VAR_UNKNOWN:
2472 	    case VAR_DICT:
2473 	    case VAR_FUNC:
2474 	    case VAR_PARTIAL:
2475 	    case VAR_SPECIAL:
2476 	    case VAR_JOB:
2477 	    case VAR_CHANNEL:
2478 		break;
2479 
2480 	    case VAR_BLOB:
2481 		if (*op != '+' || tv2->v_type != VAR_BLOB)
2482 		    break;
2483 		// BLOB += BLOB
2484 		if (tv1->vval.v_blob != NULL && tv2->vval.v_blob != NULL)
2485 		{
2486 		    blob_T  *b1 = tv1->vval.v_blob;
2487 		    blob_T  *b2 = tv2->vval.v_blob;
2488 		    int	i, len = blob_len(b2);
2489 		    for (i = 0; i < len; i++)
2490 			ga_append(&b1->bv_ga, blob_get(b2, i));
2491 		}
2492 		return OK;
2493 
2494 	    case VAR_LIST:
2495 		if (*op != '+' || tv2->v_type != VAR_LIST)
2496 		    break;
2497 		/* List += List */
2498 		if (tv1->vval.v_list != NULL && tv2->vval.v_list != NULL)
2499 		    list_extend(tv1->vval.v_list, tv2->vval.v_list, NULL);
2500 		return OK;
2501 
2502 	    case VAR_NUMBER:
2503 	    case VAR_STRING:
2504 		if (tv2->v_type == VAR_LIST)
2505 		    break;
2506 		if (*op == '+' || *op == '-')
2507 		{
2508 		    /* nr += nr  or  nr -= nr*/
2509 		    n = tv_get_number(tv1);
2510 #ifdef FEAT_FLOAT
2511 		    if (tv2->v_type == VAR_FLOAT)
2512 		    {
2513 			float_T f = n;
2514 
2515 			if (*op == '+')
2516 			    f += tv2->vval.v_float;
2517 			else
2518 			    f -= tv2->vval.v_float;
2519 			clear_tv(tv1);
2520 			tv1->v_type = VAR_FLOAT;
2521 			tv1->vval.v_float = f;
2522 		    }
2523 		    else
2524 #endif
2525 		    {
2526 			if (*op == '+')
2527 			    n += tv_get_number(tv2);
2528 			else
2529 			    n -= tv_get_number(tv2);
2530 			clear_tv(tv1);
2531 			tv1->v_type = VAR_NUMBER;
2532 			tv1->vval.v_number = n;
2533 		    }
2534 		}
2535 		else
2536 		{
2537 		    if (tv2->v_type == VAR_FLOAT)
2538 			break;
2539 
2540 		    /* str .= str */
2541 		    s = tv_get_string(tv1);
2542 		    s = concat_str(s, tv_get_string_buf(tv2, numbuf));
2543 		    clear_tv(tv1);
2544 		    tv1->v_type = VAR_STRING;
2545 		    tv1->vval.v_string = s;
2546 		}
2547 		return OK;
2548 
2549 	    case VAR_FLOAT:
2550 #ifdef FEAT_FLOAT
2551 		{
2552 		    float_T f;
2553 
2554 		    if (*op == '.' || (tv2->v_type != VAR_FLOAT
2555 				    && tv2->v_type != VAR_NUMBER
2556 				    && tv2->v_type != VAR_STRING))
2557 			break;
2558 		    if (tv2->v_type == VAR_FLOAT)
2559 			f = tv2->vval.v_float;
2560 		    else
2561 			f = tv_get_number(tv2);
2562 		    if (*op == '+')
2563 			tv1->vval.v_float += f;
2564 		    else
2565 			tv1->vval.v_float -= f;
2566 		}
2567 #endif
2568 		return OK;
2569 	}
2570     }
2571 
2572     semsg(_(e_letwrong), op);
2573     return FAIL;
2574 }
2575 
2576 /*
2577  * Evaluate the expression used in a ":for var in expr" command.
2578  * "arg" points to "var".
2579  * Set "*errp" to TRUE for an error, FALSE otherwise;
2580  * Return a pointer that holds the info.  Null when there is an error.
2581  */
2582     void *
2583 eval_for_line(
2584     char_u	*arg,
2585     int		*errp,
2586     char_u	**nextcmdp,
2587     int		skip)
2588 {
2589     forinfo_T	*fi;
2590     char_u	*expr;
2591     typval_T	tv;
2592     list_T	*l;
2593     blob_T	*b;
2594 
2595     *errp = TRUE;	/* default: there is an error */
2596 
2597     fi = (forinfo_T *)alloc_clear(sizeof(forinfo_T));
2598     if (fi == NULL)
2599 	return NULL;
2600 
2601     expr = skip_var_list(arg, &fi->fi_varcount, &fi->fi_semicolon);
2602     if (expr == NULL)
2603 	return fi;
2604 
2605     expr = skipwhite(expr);
2606     if (expr[0] != 'i' || expr[1] != 'n' || !VIM_ISWHITE(expr[2]))
2607     {
2608 	emsg(_("E690: Missing \"in\" after :for"));
2609 	return fi;
2610     }
2611 
2612     if (skip)
2613 	++emsg_skip;
2614     if (eval0(skipwhite(expr + 2), &tv, nextcmdp, !skip) == OK)
2615     {
2616 	*errp = FALSE;
2617 	if (!skip)
2618 	{
2619 	    if (tv.v_type == VAR_LIST)
2620 	    {
2621 		l = tv.vval.v_list;
2622 		if (l == NULL)
2623 		{
2624 		    // a null list is like an empty list: do nothing
2625 		    clear_tv(&tv);
2626 		}
2627 		else
2628 		{
2629 		    // No need to increment the refcount, it's already set for
2630 		    // the list being used in "tv".
2631 		    fi->fi_list = l;
2632 		    list_add_watch(l, &fi->fi_lw);
2633 		    fi->fi_lw.lw_item = l->lv_first;
2634 		}
2635 	    }
2636 	    else if (tv.v_type == VAR_BLOB)
2637 	    {
2638 		b = tv.vval.v_blob;
2639 		if (b == NULL)
2640 		    clear_tv(&tv);
2641 		else
2642 		{
2643 		    // No need to increment the refcount, it's already set for
2644 		    // the blob being used in "tv".
2645 		    fi->fi_blob = b;
2646 		    fi->fi_bi = 0;
2647 		}
2648 	    }
2649 	    else
2650 	    {
2651 		emsg(_(e_listreq));
2652 		clear_tv(&tv);
2653 	    }
2654 	}
2655     }
2656     if (skip)
2657 	--emsg_skip;
2658 
2659     return fi;
2660 }
2661 
2662 /*
2663  * Use the first item in a ":for" list.  Advance to the next.
2664  * Assign the values to the variable (list).  "arg" points to the first one.
2665  * Return TRUE when a valid item was found, FALSE when at end of list or
2666  * something wrong.
2667  */
2668     int
2669 next_for_item(void *fi_void, char_u *arg)
2670 {
2671     forinfo_T	*fi = (forinfo_T *)fi_void;
2672     int		result;
2673     listitem_T	*item;
2674 
2675     if (fi->fi_blob != NULL)
2676     {
2677 	typval_T	tv;
2678 
2679 	if (fi->fi_bi >= blob_len(fi->fi_blob))
2680 	    return FALSE;
2681 	tv.v_type = VAR_NUMBER;
2682 	tv.v_lock = VAR_FIXED;
2683 	tv.vval.v_number = blob_get(fi->fi_blob, fi->fi_bi);
2684 	++fi->fi_bi;
2685 	return ex_let_vars(arg, &tv, TRUE,
2686 			      fi->fi_semicolon, fi->fi_varcount, NULL) == OK;
2687     }
2688 
2689     item = fi->fi_lw.lw_item;
2690     if (item == NULL)
2691 	result = FALSE;
2692     else
2693     {
2694 	fi->fi_lw.lw_item = item->li_next;
2695 	result = (ex_let_vars(arg, &item->li_tv, TRUE,
2696 			      fi->fi_semicolon, fi->fi_varcount, NULL) == OK);
2697     }
2698     return result;
2699 }
2700 
2701 /*
2702  * Free the structure used to store info used by ":for".
2703  */
2704     void
2705 free_for_info(void *fi_void)
2706 {
2707     forinfo_T    *fi = (forinfo_T *)fi_void;
2708 
2709     if (fi != NULL && fi->fi_list != NULL)
2710     {
2711 	list_rem_watch(fi->fi_list, &fi->fi_lw);
2712 	list_unref(fi->fi_list);
2713     }
2714     if (fi != NULL && fi->fi_blob != NULL)
2715 	blob_unref(fi->fi_blob);
2716     vim_free(fi);
2717 }
2718 
2719 #if defined(FEAT_CMDL_COMPL) || defined(PROTO)
2720 
2721     void
2722 set_context_for_expression(
2723     expand_T	*xp,
2724     char_u	*arg,
2725     cmdidx_T	cmdidx)
2726 {
2727     int		got_eq = FALSE;
2728     int		c;
2729     char_u	*p;
2730 
2731     if (cmdidx == CMD_let)
2732     {
2733 	xp->xp_context = EXPAND_USER_VARS;
2734 	if (vim_strpbrk(arg, (char_u *)"\"'+-*/%.=!?~|&$([<>,#") == NULL)
2735 	{
2736 	    /* ":let var1 var2 ...": find last space. */
2737 	    for (p = arg + STRLEN(arg); p >= arg; )
2738 	    {
2739 		xp->xp_pattern = p;
2740 		MB_PTR_BACK(arg, p);
2741 		if (VIM_ISWHITE(*p))
2742 		    break;
2743 	    }
2744 	    return;
2745 	}
2746     }
2747     else
2748 	xp->xp_context = cmdidx == CMD_call ? EXPAND_FUNCTIONS
2749 							  : EXPAND_EXPRESSION;
2750     while ((xp->xp_pattern = vim_strpbrk(arg,
2751 				  (char_u *)"\"'+-*/%.=!?~|&$([<>,#")) != NULL)
2752     {
2753 	c = *xp->xp_pattern;
2754 	if (c == '&')
2755 	{
2756 	    c = xp->xp_pattern[1];
2757 	    if (c == '&')
2758 	    {
2759 		++xp->xp_pattern;
2760 		xp->xp_context = cmdidx != CMD_let || got_eq
2761 					 ? EXPAND_EXPRESSION : EXPAND_NOTHING;
2762 	    }
2763 	    else if (c != ' ')
2764 	    {
2765 		xp->xp_context = EXPAND_SETTINGS;
2766 		if ((c == 'l' || c == 'g') && xp->xp_pattern[2] == ':')
2767 		    xp->xp_pattern += 2;
2768 
2769 	    }
2770 	}
2771 	else if (c == '$')
2772 	{
2773 	    /* environment variable */
2774 	    xp->xp_context = EXPAND_ENV_VARS;
2775 	}
2776 	else if (c == '=')
2777 	{
2778 	    got_eq = TRUE;
2779 	    xp->xp_context = EXPAND_EXPRESSION;
2780 	}
2781 	else if (c == '#'
2782 		&& xp->xp_context == EXPAND_EXPRESSION)
2783 	{
2784 	    /* Autoload function/variable contains '#'. */
2785 	    break;
2786 	}
2787 	else if ((c == '<' || c == '#')
2788 		&& xp->xp_context == EXPAND_FUNCTIONS
2789 		&& vim_strchr(xp->xp_pattern, '(') == NULL)
2790 	{
2791 	    /* Function name can start with "<SNR>" and contain '#'. */
2792 	    break;
2793 	}
2794 	else if (cmdidx != CMD_let || got_eq)
2795 	{
2796 	    if (c == '"')	    /* string */
2797 	    {
2798 		while ((c = *++xp->xp_pattern) != NUL && c != '"')
2799 		    if (c == '\\' && xp->xp_pattern[1] != NUL)
2800 			++xp->xp_pattern;
2801 		xp->xp_context = EXPAND_NOTHING;
2802 	    }
2803 	    else if (c == '\'')	    /* literal string */
2804 	    {
2805 		/* Trick: '' is like stopping and starting a literal string. */
2806 		while ((c = *++xp->xp_pattern) != NUL && c != '\'')
2807 		    /* skip */ ;
2808 		xp->xp_context = EXPAND_NOTHING;
2809 	    }
2810 	    else if (c == '|')
2811 	    {
2812 		if (xp->xp_pattern[1] == '|')
2813 		{
2814 		    ++xp->xp_pattern;
2815 		    xp->xp_context = EXPAND_EXPRESSION;
2816 		}
2817 		else
2818 		    xp->xp_context = EXPAND_COMMANDS;
2819 	    }
2820 	    else
2821 		xp->xp_context = EXPAND_EXPRESSION;
2822 	}
2823 	else
2824 	    /* Doesn't look like something valid, expand as an expression
2825 	     * anyway. */
2826 	    xp->xp_context = EXPAND_EXPRESSION;
2827 	arg = xp->xp_pattern;
2828 	if (*arg != NUL)
2829 	    while ((c = *++arg) != NUL && (c == ' ' || c == '\t'))
2830 		/* skip */ ;
2831     }
2832     xp->xp_pattern = arg;
2833 }
2834 
2835 #endif /* FEAT_CMDL_COMPL */
2836 
2837 /*
2838  * ":unlet[!] var1 ... " command.
2839  */
2840     void
2841 ex_unlet(exarg_T *eap)
2842 {
2843     ex_unletlock(eap, eap->arg, 0);
2844 }
2845 
2846 /*
2847  * ":lockvar" and ":unlockvar" commands
2848  */
2849     void
2850 ex_lockvar(exarg_T *eap)
2851 {
2852     char_u	*arg = eap->arg;
2853     int		deep = 2;
2854 
2855     if (eap->forceit)
2856 	deep = -1;
2857     else if (vim_isdigit(*arg))
2858     {
2859 	deep = getdigits(&arg);
2860 	arg = skipwhite(arg);
2861     }
2862 
2863     ex_unletlock(eap, arg, deep);
2864 }
2865 
2866 /*
2867  * ":unlet", ":lockvar" and ":unlockvar" are quite similar.
2868  */
2869     static void
2870 ex_unletlock(
2871     exarg_T	*eap,
2872     char_u	*argstart,
2873     int		deep)
2874 {
2875     char_u	*arg = argstart;
2876     char_u	*name_end;
2877     int		error = FALSE;
2878     lval_T	lv;
2879 
2880     do
2881     {
2882 	if (*arg == '$')
2883 	{
2884 	    char_u    *name = ++arg;
2885 
2886 	    if (get_env_len(&arg) == 0)
2887 	    {
2888 		semsg(_(e_invarg2), name - 1);
2889 		return;
2890 	    }
2891 	    vim_unsetenv(name);
2892 	    arg = skipwhite(arg);
2893 	    continue;
2894 	}
2895 
2896 	/* Parse the name and find the end. */
2897 	name_end = get_lval(arg, NULL, &lv, TRUE, eap->skip || error, 0,
2898 							     FNE_CHECK_START);
2899 	if (lv.ll_name == NULL)
2900 	    error = TRUE;	    /* error but continue parsing */
2901 	if (name_end == NULL || (!VIM_ISWHITE(*name_end)
2902 						   && !ends_excmd(*name_end)))
2903 	{
2904 	    if (name_end != NULL)
2905 	    {
2906 		emsg_severe = TRUE;
2907 		emsg(_(e_trailing));
2908 	    }
2909 	    if (!(eap->skip || error))
2910 		clear_lval(&lv);
2911 	    break;
2912 	}
2913 
2914 	if (!error && !eap->skip)
2915 	{
2916 	    if (eap->cmdidx == CMD_unlet)
2917 	    {
2918 		if (do_unlet_var(&lv, name_end, eap->forceit) == FAIL)
2919 		    error = TRUE;
2920 	    }
2921 	    else
2922 	    {
2923 		if (do_lock_var(&lv, name_end, deep,
2924 					  eap->cmdidx == CMD_lockvar) == FAIL)
2925 		    error = TRUE;
2926 	    }
2927 	}
2928 
2929 	if (!eap->skip)
2930 	    clear_lval(&lv);
2931 
2932 	arg = skipwhite(name_end);
2933     } while (!ends_excmd(*arg));
2934 
2935     eap->nextcmd = check_nextcmd(arg);
2936 }
2937 
2938     static int
2939 do_unlet_var(
2940     lval_T	*lp,
2941     char_u	*name_end,
2942     int		forceit)
2943 {
2944     int		ret = OK;
2945     int		cc;
2946 
2947     if (lp->ll_tv == NULL)
2948     {
2949 	cc = *name_end;
2950 	*name_end = NUL;
2951 
2952 	/* Normal name or expanded name. */
2953 	if (do_unlet(lp->ll_name, forceit) == FAIL)
2954 	    ret = FAIL;
2955 	*name_end = cc;
2956     }
2957     else if ((lp->ll_list != NULL
2958 		   && tv_check_lock(lp->ll_list->lv_lock, lp->ll_name, FALSE))
2959 	    || (lp->ll_dict != NULL
2960 		  && tv_check_lock(lp->ll_dict->dv_lock, lp->ll_name, FALSE)))
2961 	return FAIL;
2962     else if (lp->ll_range)
2963     {
2964 	listitem_T    *li;
2965 	listitem_T    *ll_li = lp->ll_li;
2966 	int	      ll_n1 = lp->ll_n1;
2967 
2968 	while (ll_li != NULL && (lp->ll_empty2 || lp->ll_n2 >= ll_n1))
2969 	{
2970 	    li = ll_li->li_next;
2971 	    if (tv_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
2972 		return FAIL;
2973 	    ll_li = li;
2974 	    ++ll_n1;
2975 	}
2976 
2977 	/* Delete a range of List items. */
2978 	while (lp->ll_li != NULL && (lp->ll_empty2 || lp->ll_n2 >= lp->ll_n1))
2979 	{
2980 	    li = lp->ll_li->li_next;
2981 	    listitem_remove(lp->ll_list, lp->ll_li);
2982 	    lp->ll_li = li;
2983 	    ++lp->ll_n1;
2984 	}
2985     }
2986     else
2987     {
2988 	if (lp->ll_list != NULL)
2989 	    /* unlet a List item. */
2990 	    listitem_remove(lp->ll_list, lp->ll_li);
2991 	else
2992 	    /* unlet a Dictionary item. */
2993 	    dictitem_remove(lp->ll_dict, lp->ll_di);
2994     }
2995 
2996     return ret;
2997 }
2998 
2999 /*
3000  * "unlet" a variable.  Return OK if it existed, FAIL if not.
3001  * When "forceit" is TRUE don't complain if the variable doesn't exist.
3002  */
3003     int
3004 do_unlet(char_u *name, int forceit)
3005 {
3006     hashtab_T	*ht;
3007     hashitem_T	*hi;
3008     char_u	*varname;
3009     dict_T	*d;
3010     dictitem_T	*di;
3011 
3012     ht = find_var_ht(name, &varname);
3013     if (ht != NULL && *varname != NUL)
3014     {
3015 	d = get_current_funccal_dict(ht);
3016 	if (d == NULL)
3017 	{
3018 	    if (ht == &globvarht)
3019 		d = &globvardict;
3020 	    else if (ht == &compat_hashtab)
3021 		d = &vimvardict;
3022 	    else
3023 	    {
3024 		di = find_var_in_ht(ht, *name, (char_u *)"", FALSE);
3025 		d = di == NULL ? NULL : di->di_tv.vval.v_dict;
3026 	    }
3027 	    if (d == NULL)
3028 	    {
3029 		internal_error("do_unlet()");
3030 		return FAIL;
3031 	    }
3032 	}
3033 	hi = hash_find(ht, varname);
3034 	if (HASHITEM_EMPTY(hi))
3035 	    hi = find_hi_in_scoped_ht(name, &ht);
3036 	if (hi != NULL && !HASHITEM_EMPTY(hi))
3037 	{
3038 	    di = HI2DI(hi);
3039 	    if (var_check_fixed(di->di_flags, name, FALSE)
3040 		    || var_check_ro(di->di_flags, name, FALSE)
3041 		    || tv_check_lock(d->dv_lock, name, FALSE))
3042 		return FAIL;
3043 
3044 	    delete_var(ht, hi);
3045 	    return OK;
3046 	}
3047     }
3048     if (forceit)
3049 	return OK;
3050     semsg(_("E108: No such variable: \"%s\""), name);
3051     return FAIL;
3052 }
3053 
3054 /*
3055  * Lock or unlock variable indicated by "lp".
3056  * "deep" is the levels to go (-1 for unlimited);
3057  * "lock" is TRUE for ":lockvar", FALSE for ":unlockvar".
3058  */
3059     static int
3060 do_lock_var(
3061     lval_T	*lp,
3062     char_u	*name_end,
3063     int		deep,
3064     int		lock)
3065 {
3066     int		ret = OK;
3067     int		cc;
3068     dictitem_T	*di;
3069 
3070     if (deep == 0)	/* nothing to do */
3071 	return OK;
3072 
3073     if (lp->ll_tv == NULL)
3074     {
3075 	cc = *name_end;
3076 	*name_end = NUL;
3077 
3078 	/* Normal name or expanded name. */
3079 	di = find_var(lp->ll_name, NULL, TRUE);
3080 	if (di == NULL)
3081 	    ret = FAIL;
3082 	else if ((di->di_flags & DI_FLAGS_FIX)
3083 			&& di->di_tv.v_type != VAR_DICT
3084 			&& di->di_tv.v_type != VAR_LIST)
3085 	    /* For historic reasons this error is not given for a list or dict.
3086 	     * E.g., the b: dict could be locked/unlocked. */
3087 	    semsg(_("E940: Cannot lock or unlock variable %s"), lp->ll_name);
3088 	else
3089 	{
3090 	    if (lock)
3091 		di->di_flags |= DI_FLAGS_LOCK;
3092 	    else
3093 		di->di_flags &= ~DI_FLAGS_LOCK;
3094 	    item_lock(&di->di_tv, deep, lock);
3095 	}
3096 	*name_end = cc;
3097     }
3098     else if (lp->ll_range)
3099     {
3100 	listitem_T    *li = lp->ll_li;
3101 
3102 	/* (un)lock a range of List items. */
3103 	while (li != NULL && (lp->ll_empty2 || lp->ll_n2 >= lp->ll_n1))
3104 	{
3105 	    item_lock(&li->li_tv, deep, lock);
3106 	    li = li->li_next;
3107 	    ++lp->ll_n1;
3108 	}
3109     }
3110     else if (lp->ll_list != NULL)
3111 	/* (un)lock a List item. */
3112 	item_lock(&lp->ll_li->li_tv, deep, lock);
3113     else
3114 	/* (un)lock a Dictionary item. */
3115 	item_lock(&lp->ll_di->di_tv, deep, lock);
3116 
3117     return ret;
3118 }
3119 
3120 /*
3121  * Lock or unlock an item.  "deep" is nr of levels to go.
3122  */
3123     static void
3124 item_lock(typval_T *tv, int deep, int lock)
3125 {
3126     static int	recurse = 0;
3127     list_T	*l;
3128     listitem_T	*li;
3129     dict_T	*d;
3130     blob_T	*b;
3131     hashitem_T	*hi;
3132     int		todo;
3133 
3134     if (recurse >= DICT_MAXNEST)
3135     {
3136 	emsg(_("E743: variable nested too deep for (un)lock"));
3137 	return;
3138     }
3139     if (deep == 0)
3140 	return;
3141     ++recurse;
3142 
3143     /* lock/unlock the item itself */
3144     if (lock)
3145 	tv->v_lock |= VAR_LOCKED;
3146     else
3147 	tv->v_lock &= ~VAR_LOCKED;
3148 
3149     switch (tv->v_type)
3150     {
3151 	case VAR_UNKNOWN:
3152 	case VAR_NUMBER:
3153 	case VAR_STRING:
3154 	case VAR_FUNC:
3155 	case VAR_PARTIAL:
3156 	case VAR_FLOAT:
3157 	case VAR_SPECIAL:
3158 	case VAR_JOB:
3159 	case VAR_CHANNEL:
3160 	    break;
3161 
3162 	case VAR_BLOB:
3163 	    if ((b = tv->vval.v_blob) != NULL)
3164 	    {
3165 		if (lock)
3166 		    b->bv_lock |= VAR_LOCKED;
3167 		else
3168 		    b->bv_lock &= ~VAR_LOCKED;
3169 	    }
3170 	    break;
3171 	case VAR_LIST:
3172 	    if ((l = tv->vval.v_list) != NULL)
3173 	    {
3174 		if (lock)
3175 		    l->lv_lock |= VAR_LOCKED;
3176 		else
3177 		    l->lv_lock &= ~VAR_LOCKED;
3178 		if (deep < 0 || deep > 1)
3179 		    /* recursive: lock/unlock the items the List contains */
3180 		    for (li = l->lv_first; li != NULL; li = li->li_next)
3181 			item_lock(&li->li_tv, deep - 1, lock);
3182 	    }
3183 	    break;
3184 	case VAR_DICT:
3185 	    if ((d = tv->vval.v_dict) != NULL)
3186 	    {
3187 		if (lock)
3188 		    d->dv_lock |= VAR_LOCKED;
3189 		else
3190 		    d->dv_lock &= ~VAR_LOCKED;
3191 		if (deep < 0 || deep > 1)
3192 		{
3193 		    /* recursive: lock/unlock the items the List contains */
3194 		    todo = (int)d->dv_hashtab.ht_used;
3195 		    for (hi = d->dv_hashtab.ht_array; todo > 0; ++hi)
3196 		    {
3197 			if (!HASHITEM_EMPTY(hi))
3198 			{
3199 			    --todo;
3200 			    item_lock(&HI2DI(hi)->di_tv, deep - 1, lock);
3201 			}
3202 		    }
3203 		}
3204 	    }
3205     }
3206     --recurse;
3207 }
3208 
3209 #if (defined(FEAT_MENU) && defined(FEAT_MULTI_LANG)) || defined(PROTO)
3210 /*
3211  * Delete all "menutrans_" variables.
3212  */
3213     void
3214 del_menutrans_vars(void)
3215 {
3216     hashitem_T	*hi;
3217     int		todo;
3218 
3219     hash_lock(&globvarht);
3220     todo = (int)globvarht.ht_used;
3221     for (hi = globvarht.ht_array; todo > 0 && !got_int; ++hi)
3222     {
3223 	if (!HASHITEM_EMPTY(hi))
3224 	{
3225 	    --todo;
3226 	    if (STRNCMP(HI2DI(hi)->di_key, "menutrans_", 10) == 0)
3227 		delete_var(&globvarht, hi);
3228 	}
3229     }
3230     hash_unlock(&globvarht);
3231 }
3232 #endif
3233 
3234 #if defined(FEAT_CMDL_COMPL) || defined(PROTO)
3235 
3236 /*
3237  * Local string buffer for the next two functions to store a variable name
3238  * with its prefix. Allocated in cat_prefix_varname(), freed later in
3239  * get_user_var_name().
3240  */
3241 
3242 static char_u	*varnamebuf = NULL;
3243 static int	varnamebuflen = 0;
3244 
3245 /*
3246  * Function to concatenate a prefix and a variable name.
3247  */
3248     static char_u *
3249 cat_prefix_varname(int prefix, char_u *name)
3250 {
3251     int		len;
3252 
3253     len = (int)STRLEN(name) + 3;
3254     if (len > varnamebuflen)
3255     {
3256 	vim_free(varnamebuf);
3257 	len += 10;			/* some additional space */
3258 	varnamebuf = alloc(len);
3259 	if (varnamebuf == NULL)
3260 	{
3261 	    varnamebuflen = 0;
3262 	    return NULL;
3263 	}
3264 	varnamebuflen = len;
3265     }
3266     *varnamebuf = prefix;
3267     varnamebuf[1] = ':';
3268     STRCPY(varnamebuf + 2, name);
3269     return varnamebuf;
3270 }
3271 
3272 /*
3273  * Function given to ExpandGeneric() to obtain the list of user defined
3274  * (global/buffer/window/built-in) variable names.
3275  */
3276     char_u *
3277 get_user_var_name(expand_T *xp, int idx)
3278 {
3279     static long_u	gdone;
3280     static long_u	bdone;
3281     static long_u	wdone;
3282     static long_u	tdone;
3283     static int		vidx;
3284     static hashitem_T	*hi;
3285     hashtab_T		*ht;
3286 
3287     if (idx == 0)
3288     {
3289 	gdone = bdone = wdone = vidx = 0;
3290 	tdone = 0;
3291     }
3292 
3293     /* Global variables */
3294     if (gdone < globvarht.ht_used)
3295     {
3296 	if (gdone++ == 0)
3297 	    hi = globvarht.ht_array;
3298 	else
3299 	    ++hi;
3300 	while (HASHITEM_EMPTY(hi))
3301 	    ++hi;
3302 	if (STRNCMP("g:", xp->xp_pattern, 2) == 0)
3303 	    return cat_prefix_varname('g', hi->hi_key);
3304 	return hi->hi_key;
3305     }
3306 
3307     /* b: variables */
3308     ht = &curbuf->b_vars->dv_hashtab;
3309     if (bdone < ht->ht_used)
3310     {
3311 	if (bdone++ == 0)
3312 	    hi = ht->ht_array;
3313 	else
3314 	    ++hi;
3315 	while (HASHITEM_EMPTY(hi))
3316 	    ++hi;
3317 	return cat_prefix_varname('b', hi->hi_key);
3318     }
3319 
3320     /* w: variables */
3321     ht = &curwin->w_vars->dv_hashtab;
3322     if (wdone < ht->ht_used)
3323     {
3324 	if (wdone++ == 0)
3325 	    hi = ht->ht_array;
3326 	else
3327 	    ++hi;
3328 	while (HASHITEM_EMPTY(hi))
3329 	    ++hi;
3330 	return cat_prefix_varname('w', hi->hi_key);
3331     }
3332 
3333     /* t: variables */
3334     ht = &curtab->tp_vars->dv_hashtab;
3335     if (tdone < ht->ht_used)
3336     {
3337 	if (tdone++ == 0)
3338 	    hi = ht->ht_array;
3339 	else
3340 	    ++hi;
3341 	while (HASHITEM_EMPTY(hi))
3342 	    ++hi;
3343 	return cat_prefix_varname('t', hi->hi_key);
3344     }
3345 
3346     /* v: variables */
3347     if (vidx < VV_LEN)
3348 	return cat_prefix_varname('v', (char_u *)vimvars[vidx++].vv_name);
3349 
3350     VIM_CLEAR(varnamebuf);
3351     varnamebuflen = 0;
3352     return NULL;
3353 }
3354 
3355 #endif /* FEAT_CMDL_COMPL */
3356 
3357 /*
3358  * Return TRUE if "pat" matches "text".
3359  * Does not use 'cpo' and always uses 'magic'.
3360  */
3361     static int
3362 pattern_match(char_u *pat, char_u *text, int ic)
3363 {
3364     int		matches = FALSE;
3365     char_u	*save_cpo;
3366     regmatch_T	regmatch;
3367 
3368     /* avoid 'l' flag in 'cpoptions' */
3369     save_cpo = p_cpo;
3370     p_cpo = (char_u *)"";
3371     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
3372     if (regmatch.regprog != NULL)
3373     {
3374 	regmatch.rm_ic = ic;
3375 	matches = vim_regexec_nl(&regmatch, text, (colnr_T)0);
3376 	vim_regfree(regmatch.regprog);
3377     }
3378     p_cpo = save_cpo;
3379     return matches;
3380 }
3381 
3382 /*
3383  * The "evaluate" argument: When FALSE, the argument is only parsed but not
3384  * executed.  The function may return OK, but the rettv will be of type
3385  * VAR_UNKNOWN.  The function still returns FAIL for a syntax error.
3386  */
3387 
3388 /*
3389  * Handle zero level expression.
3390  * This calls eval1() and handles error message and nextcmd.
3391  * Put the result in "rettv" when returning OK and "evaluate" is TRUE.
3392  * Note: "rettv.v_lock" is not set.
3393  * Return OK or FAIL.
3394  */
3395     int
3396 eval0(
3397     char_u	*arg,
3398     typval_T	*rettv,
3399     char_u	**nextcmd,
3400     int		evaluate)
3401 {
3402     int		ret;
3403     char_u	*p;
3404     int		did_emsg_before = did_emsg;
3405     int		called_emsg_before = called_emsg;
3406 
3407     p = skipwhite(arg);
3408     ret = eval1(&p, rettv, evaluate);
3409     if (ret == FAIL || !ends_excmd(*p))
3410     {
3411 	if (ret != FAIL)
3412 	    clear_tv(rettv);
3413 	/*
3414 	 * Report the invalid expression unless the expression evaluation has
3415 	 * been cancelled due to an aborting error, an interrupt, or an
3416 	 * exception, or we already gave a more specific error.
3417 	 * Also check called_emsg for when using assert_fails().
3418 	 */
3419 	if (!aborting() && did_emsg == did_emsg_before
3420 					  && called_emsg == called_emsg_before)
3421 	    semsg(_(e_invexpr2), arg);
3422 	ret = FAIL;
3423     }
3424     if (nextcmd != NULL)
3425 	*nextcmd = check_nextcmd(p);
3426 
3427     return ret;
3428 }
3429 
3430 /*
3431  * Handle top level expression:
3432  *	expr2 ? expr1 : expr1
3433  *
3434  * "arg" must point to the first non-white of the expression.
3435  * "arg" is advanced to the next non-white after the recognized expression.
3436  *
3437  * Note: "rettv.v_lock" is not set.
3438  *
3439  * Return OK or FAIL.
3440  */
3441     int
3442 eval1(char_u **arg, typval_T *rettv, int evaluate)
3443 {
3444     int		result;
3445     typval_T	var2;
3446 
3447     /*
3448      * Get the first variable.
3449      */
3450     if (eval2(arg, rettv, evaluate) == FAIL)
3451 	return FAIL;
3452 
3453     if ((*arg)[0] == '?')
3454     {
3455 	result = FALSE;
3456 	if (evaluate)
3457 	{
3458 	    int		error = FALSE;
3459 
3460 	    if (tv_get_number_chk(rettv, &error) != 0)
3461 		result = TRUE;
3462 	    clear_tv(rettv);
3463 	    if (error)
3464 		return FAIL;
3465 	}
3466 
3467 	/*
3468 	 * Get the second variable.
3469 	 */
3470 	*arg = skipwhite(*arg + 1);
3471 	if (eval1(arg, rettv, evaluate && result) == FAIL) /* recursive! */
3472 	    return FAIL;
3473 
3474 	/*
3475 	 * Check for the ":".
3476 	 */
3477 	if ((*arg)[0] != ':')
3478 	{
3479 	    emsg(_("E109: Missing ':' after '?'"));
3480 	    if (evaluate && result)
3481 		clear_tv(rettv);
3482 	    return FAIL;
3483 	}
3484 
3485 	/*
3486 	 * Get the third variable.
3487 	 */
3488 	*arg = skipwhite(*arg + 1);
3489 	if (eval1(arg, &var2, evaluate && !result) == FAIL) /* recursive! */
3490 	{
3491 	    if (evaluate && result)
3492 		clear_tv(rettv);
3493 	    return FAIL;
3494 	}
3495 	if (evaluate && !result)
3496 	    *rettv = var2;
3497     }
3498 
3499     return OK;
3500 }
3501 
3502 /*
3503  * Handle first level expression:
3504  *	expr2 || expr2 || expr2	    logical OR
3505  *
3506  * "arg" must point to the first non-white of the expression.
3507  * "arg" is advanced to the next non-white after the recognized expression.
3508  *
3509  * Return OK or FAIL.
3510  */
3511     static int
3512 eval2(char_u **arg, typval_T *rettv, int evaluate)
3513 {
3514     typval_T	var2;
3515     long	result;
3516     int		first;
3517     int		error = FALSE;
3518 
3519     /*
3520      * Get the first variable.
3521      */
3522     if (eval3(arg, rettv, evaluate) == FAIL)
3523 	return FAIL;
3524 
3525     /*
3526      * Repeat until there is no following "||".
3527      */
3528     first = TRUE;
3529     result = FALSE;
3530     while ((*arg)[0] == '|' && (*arg)[1] == '|')
3531     {
3532 	if (evaluate && first)
3533 	{
3534 	    if (tv_get_number_chk(rettv, &error) != 0)
3535 		result = TRUE;
3536 	    clear_tv(rettv);
3537 	    if (error)
3538 		return FAIL;
3539 	    first = FALSE;
3540 	}
3541 
3542 	/*
3543 	 * Get the second variable.
3544 	 */
3545 	*arg = skipwhite(*arg + 2);
3546 	if (eval3(arg, &var2, evaluate && !result) == FAIL)
3547 	    return FAIL;
3548 
3549 	/*
3550 	 * Compute the result.
3551 	 */
3552 	if (evaluate && !result)
3553 	{
3554 	    if (tv_get_number_chk(&var2, &error) != 0)
3555 		result = TRUE;
3556 	    clear_tv(&var2);
3557 	    if (error)
3558 		return FAIL;
3559 	}
3560 	if (evaluate)
3561 	{
3562 	    rettv->v_type = VAR_NUMBER;
3563 	    rettv->vval.v_number = result;
3564 	}
3565     }
3566 
3567     return OK;
3568 }
3569 
3570 /*
3571  * Handle second level expression:
3572  *	expr3 && expr3 && expr3	    logical AND
3573  *
3574  * "arg" must point to the first non-white of the expression.
3575  * "arg" is advanced to the next non-white after the recognized expression.
3576  *
3577  * Return OK or FAIL.
3578  */
3579     static int
3580 eval3(char_u **arg, typval_T *rettv, int evaluate)
3581 {
3582     typval_T	var2;
3583     long	result;
3584     int		first;
3585     int		error = FALSE;
3586 
3587     /*
3588      * Get the first variable.
3589      */
3590     if (eval4(arg, rettv, evaluate) == FAIL)
3591 	return FAIL;
3592 
3593     /*
3594      * Repeat until there is no following "&&".
3595      */
3596     first = TRUE;
3597     result = TRUE;
3598     while ((*arg)[0] == '&' && (*arg)[1] == '&')
3599     {
3600 	if (evaluate && first)
3601 	{
3602 	    if (tv_get_number_chk(rettv, &error) == 0)
3603 		result = FALSE;
3604 	    clear_tv(rettv);
3605 	    if (error)
3606 		return FAIL;
3607 	    first = FALSE;
3608 	}
3609 
3610 	/*
3611 	 * Get the second variable.
3612 	 */
3613 	*arg = skipwhite(*arg + 2);
3614 	if (eval4(arg, &var2, evaluate && result) == FAIL)
3615 	    return FAIL;
3616 
3617 	/*
3618 	 * Compute the result.
3619 	 */
3620 	if (evaluate && result)
3621 	{
3622 	    if (tv_get_number_chk(&var2, &error) == 0)
3623 		result = FALSE;
3624 	    clear_tv(&var2);
3625 	    if (error)
3626 		return FAIL;
3627 	}
3628 	if (evaluate)
3629 	{
3630 	    rettv->v_type = VAR_NUMBER;
3631 	    rettv->vval.v_number = result;
3632 	}
3633     }
3634 
3635     return OK;
3636 }
3637 
3638 /*
3639  * Handle third level expression:
3640  *	var1 == var2
3641  *	var1 =~ var2
3642  *	var1 != var2
3643  *	var1 !~ var2
3644  *	var1 > var2
3645  *	var1 >= var2
3646  *	var1 < var2
3647  *	var1 <= var2
3648  *	var1 is var2
3649  *	var1 isnot var2
3650  *
3651  * "arg" must point to the first non-white of the expression.
3652  * "arg" is advanced to the next non-white after the recognized expression.
3653  *
3654  * Return OK or FAIL.
3655  */
3656     static int
3657 eval4(char_u **arg, typval_T *rettv, int evaluate)
3658 {
3659     typval_T	var2;
3660     char_u	*p;
3661     int		i;
3662     exptype_T	type = TYPE_UNKNOWN;
3663     int		type_is = FALSE;    /* TRUE for "is" and "isnot" */
3664     int		len = 2;
3665     int		ic;
3666 
3667     /*
3668      * Get the first variable.
3669      */
3670     if (eval5(arg, rettv, evaluate) == FAIL)
3671 	return FAIL;
3672 
3673     p = *arg;
3674     switch (p[0])
3675     {
3676 	case '=':   if (p[1] == '=')
3677 			type = TYPE_EQUAL;
3678 		    else if (p[1] == '~')
3679 			type = TYPE_MATCH;
3680 		    break;
3681 	case '!':   if (p[1] == '=')
3682 			type = TYPE_NEQUAL;
3683 		    else if (p[1] == '~')
3684 			type = TYPE_NOMATCH;
3685 		    break;
3686 	case '>':   if (p[1] != '=')
3687 		    {
3688 			type = TYPE_GREATER;
3689 			len = 1;
3690 		    }
3691 		    else
3692 			type = TYPE_GEQUAL;
3693 		    break;
3694 	case '<':   if (p[1] != '=')
3695 		    {
3696 			type = TYPE_SMALLER;
3697 			len = 1;
3698 		    }
3699 		    else
3700 			type = TYPE_SEQUAL;
3701 		    break;
3702 	case 'i':   if (p[1] == 's')
3703 		    {
3704 			if (p[2] == 'n' && p[3] == 'o' && p[4] == 't')
3705 			    len = 5;
3706 			i = p[len];
3707 			if (!isalnum(i) && i != '_')
3708 			{
3709 			    type = len == 2 ? TYPE_EQUAL : TYPE_NEQUAL;
3710 			    type_is = TRUE;
3711 			}
3712 		    }
3713 		    break;
3714     }
3715 
3716     /*
3717      * If there is a comparative operator, use it.
3718      */
3719     if (type != TYPE_UNKNOWN)
3720     {
3721 	/* extra question mark appended: ignore case */
3722 	if (p[len] == '?')
3723 	{
3724 	    ic = TRUE;
3725 	    ++len;
3726 	}
3727 	/* extra '#' appended: match case */
3728 	else if (p[len] == '#')
3729 	{
3730 	    ic = FALSE;
3731 	    ++len;
3732 	}
3733 	/* nothing appended: use 'ignorecase' */
3734 	else
3735 	    ic = p_ic;
3736 
3737 	/*
3738 	 * Get the second variable.
3739 	 */
3740 	*arg = skipwhite(p + len);
3741 	if (eval5(arg, &var2, evaluate) == FAIL)
3742 	{
3743 	    clear_tv(rettv);
3744 	    return FAIL;
3745 	}
3746 	if (evaluate)
3747 	{
3748 	    int ret = typval_compare(rettv, &var2, type, type_is, ic);
3749 
3750 	    clear_tv(&var2);
3751 	    return ret;
3752 	}
3753     }
3754 
3755     return OK;
3756 }
3757 
3758 /*
3759  * Handle fourth level expression:
3760  *	+	number addition
3761  *	-	number subtraction
3762  *	.	string concatenation
3763  *
3764  * "arg" must point to the first non-white of the expression.
3765  * "arg" is advanced to the next non-white after the recognized expression.
3766  *
3767  * Return OK or FAIL.
3768  */
3769     static int
3770 eval5(char_u **arg, typval_T *rettv, int evaluate)
3771 {
3772     typval_T	var2;
3773     typval_T	var3;
3774     int		op;
3775     varnumber_T	n1, n2;
3776 #ifdef FEAT_FLOAT
3777     float_T	f1 = 0, f2 = 0;
3778 #endif
3779     char_u	*s1, *s2;
3780     char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
3781     char_u	*p;
3782 
3783     /*
3784      * Get the first variable.
3785      */
3786     if (eval6(arg, rettv, evaluate, FALSE) == FAIL)
3787 	return FAIL;
3788 
3789     /*
3790      * Repeat computing, until no '+', '-' or '.' is following.
3791      */
3792     for (;;)
3793     {
3794 	op = **arg;
3795 	if (op != '+' && op != '-' && op != '.')
3796 	    break;
3797 
3798 	if ((op != '+' || (rettv->v_type != VAR_LIST
3799 						 && rettv->v_type != VAR_BLOB))
3800 #ifdef FEAT_FLOAT
3801 		&& (op == '.' || rettv->v_type != VAR_FLOAT)
3802 #endif
3803 		)
3804 	{
3805 	    /* For "list + ...", an illegal use of the first operand as
3806 	     * a number cannot be determined before evaluating the 2nd
3807 	     * operand: if this is also a list, all is ok.
3808 	     * For "something . ...", "something - ..." or "non-list + ...",
3809 	     * we know that the first operand needs to be a string or number
3810 	     * without evaluating the 2nd operand.  So check before to avoid
3811 	     * side effects after an error. */
3812 	    if (evaluate && tv_get_string_chk(rettv) == NULL)
3813 	    {
3814 		clear_tv(rettv);
3815 		return FAIL;
3816 	    }
3817 	}
3818 
3819 	/*
3820 	 * Get the second variable.
3821 	 */
3822 	*arg = skipwhite(*arg + 1);
3823 	if (eval6(arg, &var2, evaluate, op == '.') == FAIL)
3824 	{
3825 	    clear_tv(rettv);
3826 	    return FAIL;
3827 	}
3828 
3829 	if (evaluate)
3830 	{
3831 	    /*
3832 	     * Compute the result.
3833 	     */
3834 	    if (op == '.')
3835 	    {
3836 		s1 = tv_get_string_buf(rettv, buf1);	/* already checked */
3837 		s2 = tv_get_string_buf_chk(&var2, buf2);
3838 		if (s2 == NULL)		/* type error ? */
3839 		{
3840 		    clear_tv(rettv);
3841 		    clear_tv(&var2);
3842 		    return FAIL;
3843 		}
3844 		p = concat_str(s1, s2);
3845 		clear_tv(rettv);
3846 		rettv->v_type = VAR_STRING;
3847 		rettv->vval.v_string = p;
3848 	    }
3849 	    else if (op == '+' && rettv->v_type == VAR_BLOB
3850 						   && var2.v_type == VAR_BLOB)
3851 	    {
3852 		blob_T  *b1 = rettv->vval.v_blob;
3853 		blob_T  *b2 = var2.vval.v_blob;
3854 		blob_T	*b = blob_alloc();
3855 		int	i;
3856 
3857 		if (b != NULL)
3858 		{
3859 		    for (i = 0; i < blob_len(b1); i++)
3860 			ga_append(&b->bv_ga, blob_get(b1, i));
3861 		    for (i = 0; i < blob_len(b2); i++)
3862 			ga_append(&b->bv_ga, blob_get(b2, i));
3863 
3864 		    clear_tv(rettv);
3865 		    rettv_blob_set(rettv, b);
3866 		}
3867 	    }
3868 	    else if (op == '+' && rettv->v_type == VAR_LIST
3869 						   && var2.v_type == VAR_LIST)
3870 	    {
3871 		/* concatenate Lists */
3872 		if (list_concat(rettv->vval.v_list, var2.vval.v_list,
3873 							       &var3) == FAIL)
3874 		{
3875 		    clear_tv(rettv);
3876 		    clear_tv(&var2);
3877 		    return FAIL;
3878 		}
3879 		clear_tv(rettv);
3880 		*rettv = var3;
3881 	    }
3882 	    else
3883 	    {
3884 		int	    error = FALSE;
3885 
3886 #ifdef FEAT_FLOAT
3887 		if (rettv->v_type == VAR_FLOAT)
3888 		{
3889 		    f1 = rettv->vval.v_float;
3890 		    n1 = 0;
3891 		}
3892 		else
3893 #endif
3894 		{
3895 		    n1 = tv_get_number_chk(rettv, &error);
3896 		    if (error)
3897 		    {
3898 			/* This can only happen for "list + non-list".  For
3899 			 * "non-list + ..." or "something - ...", we returned
3900 			 * before evaluating the 2nd operand. */
3901 			clear_tv(rettv);
3902 			return FAIL;
3903 		    }
3904 #ifdef FEAT_FLOAT
3905 		    if (var2.v_type == VAR_FLOAT)
3906 			f1 = n1;
3907 #endif
3908 		}
3909 #ifdef FEAT_FLOAT
3910 		if (var2.v_type == VAR_FLOAT)
3911 		{
3912 		    f2 = var2.vval.v_float;
3913 		    n2 = 0;
3914 		}
3915 		else
3916 #endif
3917 		{
3918 		    n2 = tv_get_number_chk(&var2, &error);
3919 		    if (error)
3920 		    {
3921 			clear_tv(rettv);
3922 			clear_tv(&var2);
3923 			return FAIL;
3924 		    }
3925 #ifdef FEAT_FLOAT
3926 		    if (rettv->v_type == VAR_FLOAT)
3927 			f2 = n2;
3928 #endif
3929 		}
3930 		clear_tv(rettv);
3931 
3932 #ifdef FEAT_FLOAT
3933 		/* If there is a float on either side the result is a float. */
3934 		if (rettv->v_type == VAR_FLOAT || var2.v_type == VAR_FLOAT)
3935 		{
3936 		    if (op == '+')
3937 			f1 = f1 + f2;
3938 		    else
3939 			f1 = f1 - f2;
3940 		    rettv->v_type = VAR_FLOAT;
3941 		    rettv->vval.v_float = f1;
3942 		}
3943 		else
3944 #endif
3945 		{
3946 		    if (op == '+')
3947 			n1 = n1 + n2;
3948 		    else
3949 			n1 = n1 - n2;
3950 		    rettv->v_type = VAR_NUMBER;
3951 		    rettv->vval.v_number = n1;
3952 		}
3953 	    }
3954 	    clear_tv(&var2);
3955 	}
3956     }
3957     return OK;
3958 }
3959 
3960 /*
3961  * Handle fifth level expression:
3962  *	*	number multiplication
3963  *	/	number division
3964  *	%	number modulo
3965  *
3966  * "arg" must point to the first non-white of the expression.
3967  * "arg" is advanced to the next non-white after the recognized expression.
3968  *
3969  * Return OK or FAIL.
3970  */
3971     static int
3972 eval6(
3973     char_u	**arg,
3974     typval_T	*rettv,
3975     int		evaluate,
3976     int		want_string)  /* after "." operator */
3977 {
3978     typval_T	var2;
3979     int		op;
3980     varnumber_T	n1, n2;
3981 #ifdef FEAT_FLOAT
3982     int		use_float = FALSE;
3983     float_T	f1 = 0, f2;
3984 #endif
3985     int		error = FALSE;
3986 
3987     /*
3988      * Get the first variable.
3989      */
3990     if (eval7(arg, rettv, evaluate, want_string) == FAIL)
3991 	return FAIL;
3992 
3993     /*
3994      * Repeat computing, until no '*', '/' or '%' is following.
3995      */
3996     for (;;)
3997     {
3998 	op = **arg;
3999 	if (op != '*' && op != '/' && op != '%')
4000 	    break;
4001 
4002 	if (evaluate)
4003 	{
4004 #ifdef FEAT_FLOAT
4005 	    if (rettv->v_type == VAR_FLOAT)
4006 	    {
4007 		f1 = rettv->vval.v_float;
4008 		use_float = TRUE;
4009 		n1 = 0;
4010 	    }
4011 	    else
4012 #endif
4013 		n1 = tv_get_number_chk(rettv, &error);
4014 	    clear_tv(rettv);
4015 	    if (error)
4016 		return FAIL;
4017 	}
4018 	else
4019 	    n1 = 0;
4020 
4021 	/*
4022 	 * Get the second variable.
4023 	 */
4024 	*arg = skipwhite(*arg + 1);
4025 	if (eval7(arg, &var2, evaluate, FALSE) == FAIL)
4026 	    return FAIL;
4027 
4028 	if (evaluate)
4029 	{
4030 #ifdef FEAT_FLOAT
4031 	    if (var2.v_type == VAR_FLOAT)
4032 	    {
4033 		if (!use_float)
4034 		{
4035 		    f1 = n1;
4036 		    use_float = TRUE;
4037 		}
4038 		f2 = var2.vval.v_float;
4039 		n2 = 0;
4040 	    }
4041 	    else
4042 #endif
4043 	    {
4044 		n2 = tv_get_number_chk(&var2, &error);
4045 		clear_tv(&var2);
4046 		if (error)
4047 		    return FAIL;
4048 #ifdef FEAT_FLOAT
4049 		if (use_float)
4050 		    f2 = n2;
4051 #endif
4052 	    }
4053 
4054 	    /*
4055 	     * Compute the result.
4056 	     * When either side is a float the result is a float.
4057 	     */
4058 #ifdef FEAT_FLOAT
4059 	    if (use_float)
4060 	    {
4061 		if (op == '*')
4062 		    f1 = f1 * f2;
4063 		else if (op == '/')
4064 		{
4065 # ifdef VMS
4066 		    /* VMS crashes on divide by zero, work around it */
4067 		    if (f2 == 0.0)
4068 		    {
4069 			if (f1 == 0)
4070 			    f1 = -1 * __F_FLT_MAX - 1L;   /* similar to NaN */
4071 			else if (f1 < 0)
4072 			    f1 = -1 * __F_FLT_MAX;
4073 			else
4074 			    f1 = __F_FLT_MAX;
4075 		    }
4076 		    else
4077 			f1 = f1 / f2;
4078 # else
4079 		    /* We rely on the floating point library to handle divide
4080 		     * by zero to result in "inf" and not a crash. */
4081 		    f1 = f1 / f2;
4082 # endif
4083 		}
4084 		else
4085 		{
4086 		    emsg(_("E804: Cannot use '%' with Float"));
4087 		    return FAIL;
4088 		}
4089 		rettv->v_type = VAR_FLOAT;
4090 		rettv->vval.v_float = f1;
4091 	    }
4092 	    else
4093 #endif
4094 	    {
4095 		if (op == '*')
4096 		    n1 = n1 * n2;
4097 		else if (op == '/')
4098 		{
4099 		    if (n2 == 0)	/* give an error message? */
4100 		    {
4101 			if (n1 == 0)
4102 			    n1 = VARNUM_MIN; /* similar to NaN */
4103 			else if (n1 < 0)
4104 			    n1 = -VARNUM_MAX;
4105 			else
4106 			    n1 = VARNUM_MAX;
4107 		    }
4108 		    else
4109 			n1 = n1 / n2;
4110 		}
4111 		else
4112 		{
4113 		    if (n2 == 0)	/* give an error message? */
4114 			n1 = 0;
4115 		    else
4116 			n1 = n1 % n2;
4117 		}
4118 		rettv->v_type = VAR_NUMBER;
4119 		rettv->vval.v_number = n1;
4120 	    }
4121 	}
4122     }
4123 
4124     return OK;
4125 }
4126 
4127 /*
4128  * Handle sixth level expression:
4129  *  number		number constant
4130  *  0zFFFFFFFF		Blob constant
4131  *  "string"		string constant
4132  *  'string'		literal string constant
4133  *  &option-name	option value
4134  *  @r			register contents
4135  *  identifier		variable value
4136  *  function()		function call
4137  *  $VAR		environment variable
4138  *  (expression)	nested expression
4139  *  [expr, expr]	List
4140  *  {key: val, key: val}  Dictionary
4141  *
4142  *  Also handle:
4143  *  ! in front		logical NOT
4144  *  - in front		unary minus
4145  *  + in front		unary plus (ignored)
4146  *  trailing []		subscript in String or List
4147  *  trailing .name	entry in Dictionary
4148  *
4149  * "arg" must point to the first non-white of the expression.
4150  * "arg" is advanced to the next non-white after the recognized expression.
4151  *
4152  * Return OK or FAIL.
4153  */
4154     static int
4155 eval7(
4156     char_u	**arg,
4157     typval_T	*rettv,
4158     int		evaluate,
4159     int		want_string UNUSED)	/* after "." operator */
4160 {
4161     varnumber_T	n;
4162     int		len;
4163     char_u	*s;
4164     char_u	*start_leader, *end_leader;
4165     int		ret = OK;
4166     char_u	*alias;
4167 
4168     /*
4169      * Initialise variable so that clear_tv() can't mistake this for a
4170      * string and free a string that isn't there.
4171      */
4172     rettv->v_type = VAR_UNKNOWN;
4173 
4174     /*
4175      * Skip '!', '-' and '+' characters.  They are handled later.
4176      */
4177     start_leader = *arg;
4178     while (**arg == '!' || **arg == '-' || **arg == '+')
4179 	*arg = skipwhite(*arg + 1);
4180     end_leader = *arg;
4181 
4182     switch (**arg)
4183     {
4184     /*
4185      * Number constant.
4186      */
4187     case '0':
4188     case '1':
4189     case '2':
4190     case '3':
4191     case '4':
4192     case '5':
4193     case '6':
4194     case '7':
4195     case '8':
4196     case '9':
4197 	{
4198 #ifdef FEAT_FLOAT
4199 		char_u *p = skipdigits(*arg + 1);
4200 		int    get_float = FALSE;
4201 
4202 		/* We accept a float when the format matches
4203 		 * "[0-9]\+\.[0-9]\+\([eE][+-]\?[0-9]\+\)\?".  This is very
4204 		 * strict to avoid backwards compatibility problems.
4205 		 * Don't look for a float after the "." operator, so that
4206 		 * ":let vers = 1.2.3" doesn't fail. */
4207 		if (!want_string && p[0] == '.' && vim_isdigit(p[1]))
4208 		{
4209 		    get_float = TRUE;
4210 		    p = skipdigits(p + 2);
4211 		    if (*p == 'e' || *p == 'E')
4212 		    {
4213 			++p;
4214 			if (*p == '-' || *p == '+')
4215 			    ++p;
4216 			if (!vim_isdigit(*p))
4217 			    get_float = FALSE;
4218 			else
4219 			    p = skipdigits(p + 1);
4220 		    }
4221 		    if (ASCII_ISALPHA(*p) || *p == '.')
4222 			get_float = FALSE;
4223 		}
4224 		if (get_float)
4225 		{
4226 		    float_T	f;
4227 
4228 		    *arg += string2float(*arg, &f);
4229 		    if (evaluate)
4230 		    {
4231 			rettv->v_type = VAR_FLOAT;
4232 			rettv->vval.v_float = f;
4233 		    }
4234 		}
4235 		else
4236 #endif
4237 		if (**arg == '0' && ((*arg)[1] == 'z' || (*arg)[1] == 'Z'))
4238 		{
4239 		    char_u  *bp;
4240 		    blob_T  *blob = NULL;  // init for gcc
4241 
4242 		    // Blob constant: 0z0123456789abcdef
4243 		    if (evaluate)
4244 			blob = blob_alloc();
4245 		    for (bp = *arg + 2; vim_isxdigit(bp[0]); bp += 2)
4246 		    {
4247 			if (!vim_isxdigit(bp[1]))
4248 			{
4249 			    if (blob != NULL)
4250 			    {
4251 				emsg(_("E973: Blob literal should have an even number of hex characters"));
4252 				ga_clear(&blob->bv_ga);
4253 				VIM_CLEAR(blob);
4254 			    }
4255 			    ret = FAIL;
4256 			    break;
4257 			}
4258 			if (blob != NULL)
4259 			    ga_append(&blob->bv_ga,
4260 					 (hex2nr(*bp) << 4) + hex2nr(*(bp+1)));
4261 			if (bp[2] == '.' && vim_isxdigit(bp[3]))
4262 			    ++bp;
4263 		    }
4264 		    if (blob != NULL)
4265 			rettv_blob_set(rettv, blob);
4266 		    *arg = bp;
4267 		}
4268 		else
4269 		{
4270 		    // decimal, hex or octal number
4271 		    vim_str2nr(*arg, NULL, &len, STR2NR_ALL, &n, NULL, 0);
4272 		    *arg += len;
4273 		    if (evaluate)
4274 		    {
4275 			rettv->v_type = VAR_NUMBER;
4276 			rettv->vval.v_number = n;
4277 		    }
4278 		}
4279 		break;
4280 	}
4281 
4282     /*
4283      * String constant: "string".
4284      */
4285     case '"':	ret = get_string_tv(arg, rettv, evaluate);
4286 		break;
4287 
4288     /*
4289      * Literal string constant: 'str''ing'.
4290      */
4291     case '\'':	ret = get_lit_string_tv(arg, rettv, evaluate);
4292 		break;
4293 
4294     /*
4295      * List: [expr, expr]
4296      */
4297     case '[':	ret = get_list_tv(arg, rettv, evaluate);
4298 		break;
4299 
4300     /*
4301      * Lambda: {arg, arg -> expr}
4302      * Dictionary: {key: val, key: val}
4303      */
4304     case '{':	ret = get_lambda_tv(arg, rettv, evaluate);
4305 		if (ret == NOTDONE)
4306 		    ret = dict_get_tv(arg, rettv, evaluate);
4307 		break;
4308 
4309     /*
4310      * Option value: &name
4311      */
4312     case '&':	ret = get_option_tv(arg, rettv, evaluate);
4313 		break;
4314 
4315     /*
4316      * Environment variable: $VAR.
4317      */
4318     case '$':	ret = get_env_tv(arg, rettv, evaluate);
4319 		break;
4320 
4321     /*
4322      * Register contents: @r.
4323      */
4324     case '@':	++*arg;
4325 		if (evaluate)
4326 		{
4327 		    rettv->v_type = VAR_STRING;
4328 		    rettv->vval.v_string = get_reg_contents(**arg,
4329 							    GREG_EXPR_SRC);
4330 		}
4331 		if (**arg != NUL)
4332 		    ++*arg;
4333 		break;
4334 
4335     /*
4336      * nested expression: (expression).
4337      */
4338     case '(':	*arg = skipwhite(*arg + 1);
4339 		ret = eval1(arg, rettv, evaluate);	/* recursive! */
4340 		if (**arg == ')')
4341 		    ++*arg;
4342 		else if (ret == OK)
4343 		{
4344 		    emsg(_("E110: Missing ')'"));
4345 		    clear_tv(rettv);
4346 		    ret = FAIL;
4347 		}
4348 		break;
4349 
4350     default:	ret = NOTDONE;
4351 		break;
4352     }
4353 
4354     if (ret == NOTDONE)
4355     {
4356 	/*
4357 	 * Must be a variable or function name.
4358 	 * Can also be a curly-braces kind of name: {expr}.
4359 	 */
4360 	s = *arg;
4361 	len = get_name_len(arg, &alias, evaluate, TRUE);
4362 	if (alias != NULL)
4363 	    s = alias;
4364 
4365 	if (len <= 0)
4366 	    ret = FAIL;
4367 	else
4368 	{
4369 	    if (**arg == '(')		/* recursive! */
4370 	    {
4371 		partial_T *partial;
4372 
4373 		if (!evaluate)
4374 		    check_vars(s, len);
4375 
4376 		/* If "s" is the name of a variable of type VAR_FUNC
4377 		 * use its contents. */
4378 		s = deref_func_name(s, &len, &partial, !evaluate);
4379 
4380 		/* Need to make a copy, in case evaluating the arguments makes
4381 		 * the name invalid. */
4382 		s = vim_strsave(s);
4383 		if (s == NULL)
4384 		    ret = FAIL;
4385 		else
4386 		    /* Invoke the function. */
4387 		    ret = get_func_tv(s, len, rettv, arg,
4388 			      curwin->w_cursor.lnum, curwin->w_cursor.lnum,
4389 			      &len, evaluate, partial, NULL);
4390 		vim_free(s);
4391 
4392 		/* If evaluate is FALSE rettv->v_type was not set in
4393 		 * get_func_tv, but it's needed in handle_subscript() to parse
4394 		 * what follows. So set it here. */
4395 		if (rettv->v_type == VAR_UNKNOWN && !evaluate && **arg == '(')
4396 		{
4397 		    rettv->vval.v_string = NULL;
4398 		    rettv->v_type = VAR_FUNC;
4399 		}
4400 
4401 		/* Stop the expression evaluation when immediately
4402 		 * aborting on error, or when an interrupt occurred or
4403 		 * an exception was thrown but not caught. */
4404 		if (aborting())
4405 		{
4406 		    if (ret == OK)
4407 			clear_tv(rettv);
4408 		    ret = FAIL;
4409 		}
4410 	    }
4411 	    else if (evaluate)
4412 		ret = get_var_tv(s, len, rettv, NULL, TRUE, FALSE);
4413 	    else
4414 	    {
4415 		check_vars(s, len);
4416 		ret = OK;
4417 	    }
4418 	}
4419 	vim_free(alias);
4420     }
4421 
4422     *arg = skipwhite(*arg);
4423 
4424     /* Handle following '[', '(' and '.' for expr[expr], expr.name,
4425      * expr(expr). */
4426     if (ret == OK)
4427 	ret = handle_subscript(arg, rettv, evaluate, TRUE);
4428 
4429     /*
4430      * Apply logical NOT and unary '-', from right to left, ignore '+'.
4431      */
4432     if (ret == OK && evaluate && end_leader > start_leader)
4433     {
4434 	int	    error = FALSE;
4435 	varnumber_T val = 0;
4436 #ifdef FEAT_FLOAT
4437 	float_T	    f = 0.0;
4438 
4439 	if (rettv->v_type == VAR_FLOAT)
4440 	    f = rettv->vval.v_float;
4441 	else
4442 #endif
4443 	    val = tv_get_number_chk(rettv, &error);
4444 	if (error)
4445 	{
4446 	    clear_tv(rettv);
4447 	    ret = FAIL;
4448 	}
4449 	else
4450 	{
4451 	    while (end_leader > start_leader)
4452 	    {
4453 		--end_leader;
4454 		if (*end_leader == '!')
4455 		{
4456 #ifdef FEAT_FLOAT
4457 		    if (rettv->v_type == VAR_FLOAT)
4458 			f = !f;
4459 		    else
4460 #endif
4461 			val = !val;
4462 		}
4463 		else if (*end_leader == '-')
4464 		{
4465 #ifdef FEAT_FLOAT
4466 		    if (rettv->v_type == VAR_FLOAT)
4467 			f = -f;
4468 		    else
4469 #endif
4470 			val = -val;
4471 		}
4472 	    }
4473 #ifdef FEAT_FLOAT
4474 	    if (rettv->v_type == VAR_FLOAT)
4475 	    {
4476 		clear_tv(rettv);
4477 		rettv->vval.v_float = f;
4478 	    }
4479 	    else
4480 #endif
4481 	    {
4482 		clear_tv(rettv);
4483 		rettv->v_type = VAR_NUMBER;
4484 		rettv->vval.v_number = val;
4485 	    }
4486 	}
4487     }
4488 
4489     return ret;
4490 }
4491 
4492 /*
4493  * Evaluate an "[expr]" or "[expr:expr]" index.  Also "dict.key".
4494  * "*arg" points to the '[' or '.'.
4495  * Returns FAIL or OK. "*arg" is advanced to after the ']'.
4496  */
4497     static int
4498 eval_index(
4499     char_u	**arg,
4500     typval_T	*rettv,
4501     int		evaluate,
4502     int		verbose)	/* give error messages */
4503 {
4504     int		empty1 = FALSE, empty2 = FALSE;
4505     typval_T	var1, var2;
4506     long	i;
4507     long	n1, n2 = 0;
4508     long	len = -1;
4509     int		range = FALSE;
4510     char_u	*s;
4511     char_u	*key = NULL;
4512 
4513     switch (rettv->v_type)
4514     {
4515 	case VAR_FUNC:
4516 	case VAR_PARTIAL:
4517 	    if (verbose)
4518 		emsg(_("E695: Cannot index a Funcref"));
4519 	    return FAIL;
4520 	case VAR_FLOAT:
4521 #ifdef FEAT_FLOAT
4522 	    if (verbose)
4523 		emsg(_(e_float_as_string));
4524 	    return FAIL;
4525 #endif
4526 	case VAR_SPECIAL:
4527 	case VAR_JOB:
4528 	case VAR_CHANNEL:
4529 	    if (verbose)
4530 		emsg(_("E909: Cannot index a special variable"));
4531 	    return FAIL;
4532 	case VAR_UNKNOWN:
4533 	    if (evaluate)
4534 		return FAIL;
4535 	    /* FALLTHROUGH */
4536 
4537 	case VAR_STRING:
4538 	case VAR_NUMBER:
4539 	case VAR_LIST:
4540 	case VAR_DICT:
4541 	case VAR_BLOB:
4542 	    break;
4543     }
4544 
4545     init_tv(&var1);
4546     init_tv(&var2);
4547     if (**arg == '.')
4548     {
4549 	/*
4550 	 * dict.name
4551 	 */
4552 	key = *arg + 1;
4553 	for (len = 0; ASCII_ISALNUM(key[len]) || key[len] == '_'; ++len)
4554 	    ;
4555 	if (len == 0)
4556 	    return FAIL;
4557 	*arg = skipwhite(key + len);
4558     }
4559     else
4560     {
4561 	/*
4562 	 * something[idx]
4563 	 *
4564 	 * Get the (first) variable from inside the [].
4565 	 */
4566 	*arg = skipwhite(*arg + 1);
4567 	if (**arg == ':')
4568 	    empty1 = TRUE;
4569 	else if (eval1(arg, &var1, evaluate) == FAIL)	/* recursive! */
4570 	    return FAIL;
4571 	else if (evaluate && tv_get_string_chk(&var1) == NULL)
4572 	{
4573 	    /* not a number or string */
4574 	    clear_tv(&var1);
4575 	    return FAIL;
4576 	}
4577 
4578 	/*
4579 	 * Get the second variable from inside the [:].
4580 	 */
4581 	if (**arg == ':')
4582 	{
4583 	    range = TRUE;
4584 	    *arg = skipwhite(*arg + 1);
4585 	    if (**arg == ']')
4586 		empty2 = TRUE;
4587 	    else if (eval1(arg, &var2, evaluate) == FAIL)	/* recursive! */
4588 	    {
4589 		if (!empty1)
4590 		    clear_tv(&var1);
4591 		return FAIL;
4592 	    }
4593 	    else if (evaluate && tv_get_string_chk(&var2) == NULL)
4594 	    {
4595 		/* not a number or string */
4596 		if (!empty1)
4597 		    clear_tv(&var1);
4598 		clear_tv(&var2);
4599 		return FAIL;
4600 	    }
4601 	}
4602 
4603 	/* Check for the ']'. */
4604 	if (**arg != ']')
4605 	{
4606 	    if (verbose)
4607 		emsg(_(e_missbrac));
4608 	    clear_tv(&var1);
4609 	    if (range)
4610 		clear_tv(&var2);
4611 	    return FAIL;
4612 	}
4613 	*arg = skipwhite(*arg + 1);	/* skip the ']' */
4614     }
4615 
4616     if (evaluate)
4617     {
4618 	n1 = 0;
4619 	if (!empty1 && rettv->v_type != VAR_DICT)
4620 	{
4621 	    n1 = tv_get_number(&var1);
4622 	    clear_tv(&var1);
4623 	}
4624 	if (range)
4625 	{
4626 	    if (empty2)
4627 		n2 = -1;
4628 	    else
4629 	    {
4630 		n2 = tv_get_number(&var2);
4631 		clear_tv(&var2);
4632 	    }
4633 	}
4634 
4635 	switch (rettv->v_type)
4636 	{
4637 	    case VAR_UNKNOWN:
4638 	    case VAR_FUNC:
4639 	    case VAR_PARTIAL:
4640 	    case VAR_FLOAT:
4641 	    case VAR_SPECIAL:
4642 	    case VAR_JOB:
4643 	    case VAR_CHANNEL:
4644 		break; /* not evaluating, skipping over subscript */
4645 
4646 	    case VAR_NUMBER:
4647 	    case VAR_STRING:
4648 		s = tv_get_string(rettv);
4649 		len = (long)STRLEN(s);
4650 		if (range)
4651 		{
4652 		    /* The resulting variable is a substring.  If the indexes
4653 		     * are out of range the result is empty. */
4654 		    if (n1 < 0)
4655 		    {
4656 			n1 = len + n1;
4657 			if (n1 < 0)
4658 			    n1 = 0;
4659 		    }
4660 		    if (n2 < 0)
4661 			n2 = len + n2;
4662 		    else if (n2 >= len)
4663 			n2 = len;
4664 		    if (n1 >= len || n2 < 0 || n1 > n2)
4665 			s = NULL;
4666 		    else
4667 			s = vim_strnsave(s + n1, (int)(n2 - n1 + 1));
4668 		}
4669 		else
4670 		{
4671 		    /* The resulting variable is a string of a single
4672 		     * character.  If the index is too big or negative the
4673 		     * result is empty. */
4674 		    if (n1 >= len || n1 < 0)
4675 			s = NULL;
4676 		    else
4677 			s = vim_strnsave(s + n1, 1);
4678 		}
4679 		clear_tv(rettv);
4680 		rettv->v_type = VAR_STRING;
4681 		rettv->vval.v_string = s;
4682 		break;
4683 
4684 	    case VAR_BLOB:
4685 		len = blob_len(rettv->vval.v_blob);
4686 		if (range)
4687 		{
4688 		    // The resulting variable is a sub-blob.  If the indexes
4689 		    // are out of range the result is empty.
4690 		    if (n1 < 0)
4691 		    {
4692 			n1 = len + n1;
4693 			if (n1 < 0)
4694 			    n1 = 0;
4695 		    }
4696 		    if (n2 < 0)
4697 			n2 = len + n2;
4698 		    else if (n2 >= len)
4699 			n2 = len - 1;
4700 		    if (n1 >= len || n2 < 0 || n1 > n2)
4701 		    {
4702 			clear_tv(rettv);
4703 			rettv->v_type = VAR_BLOB;
4704 			rettv->vval.v_blob = NULL;
4705 		    }
4706 		    else
4707 		    {
4708 			blob_T  *blob = blob_alloc();
4709 
4710 			if (blob != NULL)
4711 			{
4712 			    if (ga_grow(&blob->bv_ga, n2 - n1 + 1) == FAIL)
4713 			    {
4714 				blob_free(blob);
4715 				return FAIL;
4716 			    }
4717 			    blob->bv_ga.ga_len = n2 - n1 + 1;
4718 			    for (i = n1; i <= n2; i++)
4719 				blob_set(blob, i - n1,
4720 					      blob_get(rettv->vval.v_blob, i));
4721 
4722 			    clear_tv(rettv);
4723 			    rettv_blob_set(rettv, blob);
4724 			}
4725 		    }
4726 		}
4727 		else
4728 		{
4729 		    // The resulting variable is a string of a single
4730 		    // character.  If the index is too big or negative the
4731 		    // result is empty.
4732 		    if (n1 < len && n1 >= 0)
4733 		    {
4734 			int v = (int)blob_get(rettv->vval.v_blob, n1);
4735 
4736 			clear_tv(rettv);
4737 			rettv->v_type = VAR_NUMBER;
4738 			rettv->vval.v_number = v;
4739 		    }
4740 		    else
4741 			semsg(_(e_blobidx), n1);
4742 		}
4743 		break;
4744 
4745 	    case VAR_LIST:
4746 		len = list_len(rettv->vval.v_list);
4747 		if (n1 < 0)
4748 		    n1 = len + n1;
4749 		if (!empty1 && (n1 < 0 || n1 >= len))
4750 		{
4751 		    /* For a range we allow invalid values and return an empty
4752 		     * list.  A list index out of range is an error. */
4753 		    if (!range)
4754 		    {
4755 			if (verbose)
4756 			    semsg(_(e_listidx), n1);
4757 			return FAIL;
4758 		    }
4759 		    n1 = len;
4760 		}
4761 		if (range)
4762 		{
4763 		    list_T	*l;
4764 		    listitem_T	*item;
4765 
4766 		    if (n2 < 0)
4767 			n2 = len + n2;
4768 		    else if (n2 >= len)
4769 			n2 = len - 1;
4770 		    if (!empty2 && (n2 < 0 || n2 + 1 < n1))
4771 			n2 = -1;
4772 		    l = list_alloc();
4773 		    if (l == NULL)
4774 			return FAIL;
4775 		    for (item = list_find(rettv->vval.v_list, n1);
4776 							       n1 <= n2; ++n1)
4777 		    {
4778 			if (list_append_tv(l, &item->li_tv) == FAIL)
4779 			{
4780 			    list_free(l);
4781 			    return FAIL;
4782 			}
4783 			item = item->li_next;
4784 		    }
4785 		    clear_tv(rettv);
4786 		    rettv_list_set(rettv, l);
4787 		}
4788 		else
4789 		{
4790 		    copy_tv(&list_find(rettv->vval.v_list, n1)->li_tv, &var1);
4791 		    clear_tv(rettv);
4792 		    *rettv = var1;
4793 		}
4794 		break;
4795 
4796 	    case VAR_DICT:
4797 		if (range)
4798 		{
4799 		    if (verbose)
4800 			emsg(_(e_dictrange));
4801 		    if (len == -1)
4802 			clear_tv(&var1);
4803 		    return FAIL;
4804 		}
4805 		{
4806 		    dictitem_T	*item;
4807 
4808 		    if (len == -1)
4809 		    {
4810 			key = tv_get_string_chk(&var1);
4811 			if (key == NULL)
4812 			{
4813 			    clear_tv(&var1);
4814 			    return FAIL;
4815 			}
4816 		    }
4817 
4818 		    item = dict_find(rettv->vval.v_dict, key, (int)len);
4819 
4820 		    if (item == NULL && verbose)
4821 			semsg(_(e_dictkey), key);
4822 		    if (len == -1)
4823 			clear_tv(&var1);
4824 		    if (item == NULL)
4825 			return FAIL;
4826 
4827 		    copy_tv(&item->di_tv, &var1);
4828 		    clear_tv(rettv);
4829 		    *rettv = var1;
4830 		}
4831 		break;
4832 	}
4833     }
4834 
4835     return OK;
4836 }
4837 
4838 /*
4839  * Get an option value.
4840  * "arg" points to the '&' or '+' before the option name.
4841  * "arg" is advanced to character after the option name.
4842  * Return OK or FAIL.
4843  */
4844     int
4845 get_option_tv(
4846     char_u	**arg,
4847     typval_T	*rettv,	/* when NULL, only check if option exists */
4848     int		evaluate)
4849 {
4850     char_u	*option_end;
4851     long	numval;
4852     char_u	*stringval;
4853     int		opt_type;
4854     int		c;
4855     int		working = (**arg == '+');    /* has("+option") */
4856     int		ret = OK;
4857     int		opt_flags;
4858 
4859     /*
4860      * Isolate the option name and find its value.
4861      */
4862     option_end = find_option_end(arg, &opt_flags);
4863     if (option_end == NULL)
4864     {
4865 	if (rettv != NULL)
4866 	    semsg(_("E112: Option name missing: %s"), *arg);
4867 	return FAIL;
4868     }
4869 
4870     if (!evaluate)
4871     {
4872 	*arg = option_end;
4873 	return OK;
4874     }
4875 
4876     c = *option_end;
4877     *option_end = NUL;
4878     opt_type = get_option_value(*arg, &numval,
4879 			       rettv == NULL ? NULL : &stringval, opt_flags);
4880 
4881     if (opt_type == -3)			/* invalid name */
4882     {
4883 	if (rettv != NULL)
4884 	    semsg(_("E113: Unknown option: %s"), *arg);
4885 	ret = FAIL;
4886     }
4887     else if (rettv != NULL)
4888     {
4889 	if (opt_type == -2)		/* hidden string option */
4890 	{
4891 	    rettv->v_type = VAR_STRING;
4892 	    rettv->vval.v_string = NULL;
4893 	}
4894 	else if (opt_type == -1)	/* hidden number option */
4895 	{
4896 	    rettv->v_type = VAR_NUMBER;
4897 	    rettv->vval.v_number = 0;
4898 	}
4899 	else if (opt_type == 1)		/* number option */
4900 	{
4901 	    rettv->v_type = VAR_NUMBER;
4902 	    rettv->vval.v_number = numval;
4903 	}
4904 	else				/* string option */
4905 	{
4906 	    rettv->v_type = VAR_STRING;
4907 	    rettv->vval.v_string = stringval;
4908 	}
4909     }
4910     else if (working && (opt_type == -2 || opt_type == -1))
4911 	ret = FAIL;
4912 
4913     *option_end = c;		    /* put back for error messages */
4914     *arg = option_end;
4915 
4916     return ret;
4917 }
4918 
4919 /*
4920  * Allocate a variable for a string constant.
4921  * Return OK or FAIL.
4922  */
4923     static int
4924 get_string_tv(char_u **arg, typval_T *rettv, int evaluate)
4925 {
4926     char_u	*p;
4927     char_u	*name;
4928     int		extra = 0;
4929 
4930     /*
4931      * Find the end of the string, skipping backslashed characters.
4932      */
4933     for (p = *arg + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
4934     {
4935 	if (*p == '\\' && p[1] != NUL)
4936 	{
4937 	    ++p;
4938 	    /* A "\<x>" form occupies at least 4 characters, and produces up
4939 	     * to 6 characters: reserve space for 2 extra */
4940 	    if (*p == '<')
4941 		extra += 2;
4942 	}
4943     }
4944 
4945     if (*p != '"')
4946     {
4947 	semsg(_("E114: Missing quote: %s"), *arg);
4948 	return FAIL;
4949     }
4950 
4951     /* If only parsing, set *arg and return here */
4952     if (!evaluate)
4953     {
4954 	*arg = p + 1;
4955 	return OK;
4956     }
4957 
4958     /*
4959      * Copy the string into allocated memory, handling backslashed
4960      * characters.
4961      */
4962     name = alloc((unsigned)(p - *arg + extra));
4963     if (name == NULL)
4964 	return FAIL;
4965     rettv->v_type = VAR_STRING;
4966     rettv->vval.v_string = name;
4967 
4968     for (p = *arg + 1; *p != NUL && *p != '"'; )
4969     {
4970 	if (*p == '\\')
4971 	{
4972 	    switch (*++p)
4973 	    {
4974 		case 'b': *name++ = BS; ++p; break;
4975 		case 'e': *name++ = ESC; ++p; break;
4976 		case 'f': *name++ = FF; ++p; break;
4977 		case 'n': *name++ = NL; ++p; break;
4978 		case 'r': *name++ = CAR; ++p; break;
4979 		case 't': *name++ = TAB; ++p; break;
4980 
4981 		case 'X': /* hex: "\x1", "\x12" */
4982 		case 'x':
4983 		case 'u': /* Unicode: "\u0023" */
4984 		case 'U':
4985 			  if (vim_isxdigit(p[1]))
4986 			  {
4987 			      int	n, nr;
4988 			      int	c = toupper(*p);
4989 
4990 			      if (c == 'X')
4991 				  n = 2;
4992 			      else if (*p == 'u')
4993 				  n = 4;
4994 			      else
4995 				  n = 8;
4996 			      nr = 0;
4997 			      while (--n >= 0 && vim_isxdigit(p[1]))
4998 			      {
4999 				  ++p;
5000 				  nr = (nr << 4) + hex2nr(*p);
5001 			      }
5002 			      ++p;
5003 #ifdef FEAT_MBYTE
5004 			      /* For "\u" store the number according to
5005 			       * 'encoding'. */
5006 			      if (c != 'X')
5007 				  name += (*mb_char2bytes)(nr, name);
5008 			      else
5009 #endif
5010 				  *name++ = nr;
5011 			  }
5012 			  break;
5013 
5014 			  /* octal: "\1", "\12", "\123" */
5015 		case '0':
5016 		case '1':
5017 		case '2':
5018 		case '3':
5019 		case '4':
5020 		case '5':
5021 		case '6':
5022 		case '7': *name = *p++ - '0';
5023 			  if (*p >= '0' && *p <= '7')
5024 			  {
5025 			      *name = (*name << 3) + *p++ - '0';
5026 			      if (*p >= '0' && *p <= '7')
5027 				  *name = (*name << 3) + *p++ - '0';
5028 			  }
5029 			  ++name;
5030 			  break;
5031 
5032 			    /* Special key, e.g.: "\<C-W>" */
5033 		case '<': extra = trans_special(&p, name, TRUE, TRUE);
5034 			  if (extra != 0)
5035 			  {
5036 			      name += extra;
5037 			      break;
5038 			  }
5039 			  /* FALLTHROUGH */
5040 
5041 		default:  MB_COPY_CHAR(p, name);
5042 			  break;
5043 	    }
5044 	}
5045 	else
5046 	    MB_COPY_CHAR(p, name);
5047 
5048     }
5049     *name = NUL;
5050     if (*p != NUL) /* just in case */
5051 	++p;
5052     *arg = p;
5053 
5054     return OK;
5055 }
5056 
5057 /*
5058  * Allocate a variable for a 'str''ing' constant.
5059  * Return OK or FAIL.
5060  */
5061     static int
5062 get_lit_string_tv(char_u **arg, typval_T *rettv, int evaluate)
5063 {
5064     char_u	*p;
5065     char_u	*str;
5066     int		reduce = 0;
5067 
5068     /*
5069      * Find the end of the string, skipping ''.
5070      */
5071     for (p = *arg + 1; *p != NUL; MB_PTR_ADV(p))
5072     {
5073 	if (*p == '\'')
5074 	{
5075 	    if (p[1] != '\'')
5076 		break;
5077 	    ++reduce;
5078 	    ++p;
5079 	}
5080     }
5081 
5082     if (*p != '\'')
5083     {
5084 	semsg(_("E115: Missing quote: %s"), *arg);
5085 	return FAIL;
5086     }
5087 
5088     /* If only parsing return after setting "*arg" */
5089     if (!evaluate)
5090     {
5091 	*arg = p + 1;
5092 	return OK;
5093     }
5094 
5095     /*
5096      * Copy the string into allocated memory, handling '' to ' reduction.
5097      */
5098     str = alloc((unsigned)((p - *arg) - reduce));
5099     if (str == NULL)
5100 	return FAIL;
5101     rettv->v_type = VAR_STRING;
5102     rettv->vval.v_string = str;
5103 
5104     for (p = *arg + 1; *p != NUL; )
5105     {
5106 	if (*p == '\'')
5107 	{
5108 	    if (p[1] != '\'')
5109 		break;
5110 	    ++p;
5111 	}
5112 	MB_COPY_CHAR(p, str);
5113     }
5114     *str = NUL;
5115     *arg = p + 1;
5116 
5117     return OK;
5118 }
5119 
5120 /*
5121  * Return the function name of the partial.
5122  */
5123     char_u *
5124 partial_name(partial_T *pt)
5125 {
5126     if (pt->pt_name != NULL)
5127 	return pt->pt_name;
5128     return pt->pt_func->uf_name;
5129 }
5130 
5131     static void
5132 partial_free(partial_T *pt)
5133 {
5134     int i;
5135 
5136     for (i = 0; i < pt->pt_argc; ++i)
5137 	clear_tv(&pt->pt_argv[i]);
5138     vim_free(pt->pt_argv);
5139     dict_unref(pt->pt_dict);
5140     if (pt->pt_name != NULL)
5141     {
5142 	func_unref(pt->pt_name);
5143 	vim_free(pt->pt_name);
5144     }
5145     else
5146 	func_ptr_unref(pt->pt_func);
5147     vim_free(pt);
5148 }
5149 
5150 /*
5151  * Unreference a closure: decrement the reference count and free it when it
5152  * becomes zero.
5153  */
5154     void
5155 partial_unref(partial_T *pt)
5156 {
5157     if (pt != NULL && --pt->pt_refcount <= 0)
5158 	partial_free(pt);
5159 }
5160 
5161 static int tv_equal_recurse_limit;
5162 
5163     static int
5164 func_equal(
5165     typval_T *tv1,
5166     typval_T *tv2,
5167     int	     ic)	    /* ignore case */
5168 {
5169     char_u	*s1, *s2;
5170     dict_T	*d1, *d2;
5171     int		a1, a2;
5172     int		i;
5173 
5174     /* empty and NULL function name considered the same */
5175     s1 = tv1->v_type == VAR_FUNC ? tv1->vval.v_string
5176 					   : partial_name(tv1->vval.v_partial);
5177     if (s1 != NULL && *s1 == NUL)
5178 	s1 = NULL;
5179     s2 = tv2->v_type == VAR_FUNC ? tv2->vval.v_string
5180 					   : partial_name(tv2->vval.v_partial);
5181     if (s2 != NULL && *s2 == NUL)
5182 	s2 = NULL;
5183     if (s1 == NULL || s2 == NULL)
5184     {
5185 	if (s1 != s2)
5186 	    return FALSE;
5187     }
5188     else if (STRCMP(s1, s2) != 0)
5189 	return FALSE;
5190 
5191     /* empty dict and NULL dict is different */
5192     d1 = tv1->v_type == VAR_FUNC ? NULL : tv1->vval.v_partial->pt_dict;
5193     d2 = tv2->v_type == VAR_FUNC ? NULL : tv2->vval.v_partial->pt_dict;
5194     if (d1 == NULL || d2 == NULL)
5195     {
5196 	if (d1 != d2)
5197 	    return FALSE;
5198     }
5199     else if (!dict_equal(d1, d2, ic, TRUE))
5200 	return FALSE;
5201 
5202     /* empty list and no list considered the same */
5203     a1 = tv1->v_type == VAR_FUNC ? 0 : tv1->vval.v_partial->pt_argc;
5204     a2 = tv2->v_type == VAR_FUNC ? 0 : tv2->vval.v_partial->pt_argc;
5205     if (a1 != a2)
5206 	return FALSE;
5207     for (i = 0; i < a1; ++i)
5208 	if (!tv_equal(tv1->vval.v_partial->pt_argv + i,
5209 		      tv2->vval.v_partial->pt_argv + i, ic, TRUE))
5210 	    return FALSE;
5211 
5212     return TRUE;
5213 }
5214 
5215 /*
5216  * Return TRUE if "tv1" and "tv2" have the same value.
5217  * Compares the items just like "==" would compare them, but strings and
5218  * numbers are different.  Floats and numbers are also different.
5219  */
5220     int
5221 tv_equal(
5222     typval_T *tv1,
5223     typval_T *tv2,
5224     int	     ic,	    /* ignore case */
5225     int	     recursive)	    /* TRUE when used recursively */
5226 {
5227     char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
5228     char_u	*s1, *s2;
5229     static int  recursive_cnt = 0;	    /* catch recursive loops */
5230     int		r;
5231 
5232     /* Catch lists and dicts that have an endless loop by limiting
5233      * recursiveness to a limit.  We guess they are equal then.
5234      * A fixed limit has the problem of still taking an awful long time.
5235      * Reduce the limit every time running into it. That should work fine for
5236      * deeply linked structures that are not recursively linked and catch
5237      * recursiveness quickly. */
5238     if (!recursive)
5239 	tv_equal_recurse_limit = 1000;
5240     if (recursive_cnt >= tv_equal_recurse_limit)
5241     {
5242 	--tv_equal_recurse_limit;
5243 	return TRUE;
5244     }
5245 
5246     /* For VAR_FUNC and VAR_PARTIAL compare the function name, bound dict and
5247      * arguments. */
5248     if ((tv1->v_type == VAR_FUNC
5249 		|| (tv1->v_type == VAR_PARTIAL && tv1->vval.v_partial != NULL))
5250 	    && (tv2->v_type == VAR_FUNC
5251 		|| (tv2->v_type == VAR_PARTIAL && tv2->vval.v_partial != NULL)))
5252     {
5253 	++recursive_cnt;
5254 	r = func_equal(tv1, tv2, ic);
5255 	--recursive_cnt;
5256 	return r;
5257     }
5258 
5259     if (tv1->v_type != tv2->v_type)
5260 	return FALSE;
5261 
5262     switch (tv1->v_type)
5263     {
5264 	case VAR_LIST:
5265 	    ++recursive_cnt;
5266 	    r = list_equal(tv1->vval.v_list, tv2->vval.v_list, ic, TRUE);
5267 	    --recursive_cnt;
5268 	    return r;
5269 
5270 	case VAR_DICT:
5271 	    ++recursive_cnt;
5272 	    r = dict_equal(tv1->vval.v_dict, tv2->vval.v_dict, ic, TRUE);
5273 	    --recursive_cnt;
5274 	    return r;
5275 
5276 	case VAR_BLOB:
5277 	    return blob_equal(tv1->vval.v_blob, tv2->vval.v_blob);
5278 
5279 	case VAR_NUMBER:
5280 	    return tv1->vval.v_number == tv2->vval.v_number;
5281 
5282 	case VAR_STRING:
5283 	    s1 = tv_get_string_buf(tv1, buf1);
5284 	    s2 = tv_get_string_buf(tv2, buf2);
5285 	    return ((ic ? MB_STRICMP(s1, s2) : STRCMP(s1, s2)) == 0);
5286 
5287 	case VAR_SPECIAL:
5288 	    return tv1->vval.v_number == tv2->vval.v_number;
5289 
5290 	case VAR_FLOAT:
5291 #ifdef FEAT_FLOAT
5292 	    return tv1->vval.v_float == tv2->vval.v_float;
5293 #endif
5294 	case VAR_JOB:
5295 #ifdef FEAT_JOB_CHANNEL
5296 	    return tv1->vval.v_job == tv2->vval.v_job;
5297 #endif
5298 	case VAR_CHANNEL:
5299 #ifdef FEAT_JOB_CHANNEL
5300 	    return tv1->vval.v_channel == tv2->vval.v_channel;
5301 #endif
5302 	case VAR_FUNC:
5303 	case VAR_PARTIAL:
5304 	case VAR_UNKNOWN:
5305 	    break;
5306     }
5307 
5308     /* VAR_UNKNOWN can be the result of a invalid expression, let's say it
5309      * does not equal anything, not even itself. */
5310     return FALSE;
5311 }
5312 
5313 /*
5314  * Return the next (unique) copy ID.
5315  * Used for serializing nested structures.
5316  */
5317     int
5318 get_copyID(void)
5319 {
5320     current_copyID += COPYID_INC;
5321     return current_copyID;
5322 }
5323 
5324 /*
5325  * Garbage collection for lists and dictionaries.
5326  *
5327  * We use reference counts to be able to free most items right away when they
5328  * are no longer used.  But for composite items it's possible that it becomes
5329  * unused while the reference count is > 0: When there is a recursive
5330  * reference.  Example:
5331  *	:let l = [1, 2, 3]
5332  *	:let d = {9: l}
5333  *	:let l[1] = d
5334  *
5335  * Since this is quite unusual we handle this with garbage collection: every
5336  * once in a while find out which lists and dicts are not referenced from any
5337  * variable.
5338  *
5339  * Here is a good reference text about garbage collection (refers to Python
5340  * but it applies to all reference-counting mechanisms):
5341  *	http://python.ca/nas/python/gc/
5342  */
5343 
5344 /*
5345  * Do garbage collection for lists and dicts.
5346  * When "testing" is TRUE this is called from test_garbagecollect_now().
5347  * Return TRUE if some memory was freed.
5348  */
5349     int
5350 garbage_collect(int testing)
5351 {
5352     int		copyID;
5353     int		abort = FALSE;
5354     buf_T	*buf;
5355     win_T	*wp;
5356     int		i;
5357     int		did_free = FALSE;
5358     tabpage_T	*tp;
5359 
5360     if (!testing)
5361     {
5362 	/* Only do this once. */
5363 	want_garbage_collect = FALSE;
5364 	may_garbage_collect = FALSE;
5365 	garbage_collect_at_exit = FALSE;
5366     }
5367 
5368     /* We advance by two because we add one for items referenced through
5369      * previous_funccal. */
5370     copyID = get_copyID();
5371 
5372     /*
5373      * 1. Go through all accessible variables and mark all lists and dicts
5374      *    with copyID.
5375      */
5376 
5377     /* Don't free variables in the previous_funccal list unless they are only
5378      * referenced through previous_funccal.  This must be first, because if
5379      * the item is referenced elsewhere the funccal must not be freed. */
5380     abort = abort || set_ref_in_previous_funccal(copyID);
5381 
5382     /* script-local variables */
5383     for (i = 1; i <= ga_scripts.ga_len; ++i)
5384 	abort = abort || set_ref_in_ht(&SCRIPT_VARS(i), copyID, NULL);
5385 
5386     /* buffer-local variables */
5387     FOR_ALL_BUFFERS(buf)
5388 	abort = abort || set_ref_in_item(&buf->b_bufvar.di_tv, copyID,
5389 								  NULL, NULL);
5390 
5391     /* window-local variables */
5392     FOR_ALL_TAB_WINDOWS(tp, wp)
5393 	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
5394 								  NULL, NULL);
5395     if (aucmd_win != NULL)
5396 	abort = abort || set_ref_in_item(&aucmd_win->w_winvar.di_tv, copyID,
5397 								  NULL, NULL);
5398 
5399     /* tabpage-local variables */
5400     FOR_ALL_TABPAGES(tp)
5401 	abort = abort || set_ref_in_item(&tp->tp_winvar.di_tv, copyID,
5402 								  NULL, NULL);
5403     /* global variables */
5404     abort = abort || set_ref_in_ht(&globvarht, copyID, NULL);
5405 
5406     /* function-local variables */
5407     abort = abort || set_ref_in_call_stack(copyID);
5408 
5409     /* named functions (matters for closures) */
5410     abort = abort || set_ref_in_functions(copyID);
5411 
5412     /* function call arguments, if v:testing is set. */
5413     abort = abort || set_ref_in_func_args(copyID);
5414 
5415     /* v: vars */
5416     abort = abort || set_ref_in_ht(&vimvarht, copyID, NULL);
5417 
5418 #ifdef FEAT_LUA
5419     abort = abort || set_ref_in_lua(copyID);
5420 #endif
5421 
5422 #ifdef FEAT_PYTHON
5423     abort = abort || set_ref_in_python(copyID);
5424 #endif
5425 
5426 #ifdef FEAT_PYTHON3
5427     abort = abort || set_ref_in_python3(copyID);
5428 #endif
5429 
5430 #ifdef FEAT_JOB_CHANNEL
5431     abort = abort || set_ref_in_channel(copyID);
5432     abort = abort || set_ref_in_job(copyID);
5433 #endif
5434 #ifdef FEAT_NETBEANS_INTG
5435     abort = abort || set_ref_in_nb_channel(copyID);
5436 #endif
5437 
5438 #ifdef FEAT_TIMERS
5439     abort = abort || set_ref_in_timer(copyID);
5440 #endif
5441 
5442 #ifdef FEAT_QUICKFIX
5443     abort = abort || set_ref_in_quickfix(copyID);
5444 #endif
5445 
5446 #ifdef FEAT_TERMINAL
5447     abort = abort || set_ref_in_term(copyID);
5448 #endif
5449 
5450     if (!abort)
5451     {
5452 	/*
5453 	 * 2. Free lists and dictionaries that are not referenced.
5454 	 */
5455 	did_free = free_unref_items(copyID);
5456 
5457 	/*
5458 	 * 3. Check if any funccal can be freed now.
5459 	 *    This may call us back recursively.
5460 	 */
5461 	free_unref_funccal(copyID, testing);
5462     }
5463     else if (p_verbose > 0)
5464     {
5465 	verb_msg((char_u *)_("Not enough memory to set references, garbage collection aborted!"));
5466     }
5467 
5468     return did_free;
5469 }
5470 
5471 /*
5472  * Free lists, dictionaries, channels and jobs that are no longer referenced.
5473  */
5474     static int
5475 free_unref_items(int copyID)
5476 {
5477     int		did_free = FALSE;
5478 
5479     /* Let all "free" functions know that we are here.  This means no
5480      * dictionaries, lists, channels or jobs are to be freed, because we will
5481      * do that here. */
5482     in_free_unref_items = TRUE;
5483 
5484     /*
5485      * PASS 1: free the contents of the items.  We don't free the items
5486      * themselves yet, so that it is possible to decrement refcount counters
5487      */
5488 
5489     /* Go through the list of dicts and free items without the copyID. */
5490     did_free |= dict_free_nonref(copyID);
5491 
5492     /* Go through the list of lists and free items without the copyID. */
5493     did_free |= list_free_nonref(copyID);
5494 
5495 #ifdef FEAT_JOB_CHANNEL
5496     /* Go through the list of jobs and free items without the copyID. This
5497      * must happen before doing channels, because jobs refer to channels, but
5498      * the reference from the channel to the job isn't tracked. */
5499     did_free |= free_unused_jobs_contents(copyID, COPYID_MASK);
5500 
5501     /* Go through the list of channels and free items without the copyID.  */
5502     did_free |= free_unused_channels_contents(copyID, COPYID_MASK);
5503 #endif
5504 
5505     /*
5506      * PASS 2: free the items themselves.
5507      */
5508     dict_free_items(copyID);
5509     list_free_items(copyID);
5510 
5511 #ifdef FEAT_JOB_CHANNEL
5512     /* Go through the list of jobs and free items without the copyID. This
5513      * must happen before doing channels, because jobs refer to channels, but
5514      * the reference from the channel to the job isn't tracked. */
5515     free_unused_jobs(copyID, COPYID_MASK);
5516 
5517     /* Go through the list of channels and free items without the copyID.  */
5518     free_unused_channels(copyID, COPYID_MASK);
5519 #endif
5520 
5521     in_free_unref_items = FALSE;
5522 
5523     return did_free;
5524 }
5525 
5526 /*
5527  * Mark all lists and dicts referenced through hashtab "ht" with "copyID".
5528  * "list_stack" is used to add lists to be marked.  Can be NULL.
5529  *
5530  * Returns TRUE if setting references failed somehow.
5531  */
5532     int
5533 set_ref_in_ht(hashtab_T *ht, int copyID, list_stack_T **list_stack)
5534 {
5535     int		todo;
5536     int		abort = FALSE;
5537     hashitem_T	*hi;
5538     hashtab_T	*cur_ht;
5539     ht_stack_T	*ht_stack = NULL;
5540     ht_stack_T	*tempitem;
5541 
5542     cur_ht = ht;
5543     for (;;)
5544     {
5545 	if (!abort)
5546 	{
5547 	    /* Mark each item in the hashtab.  If the item contains a hashtab
5548 	     * it is added to ht_stack, if it contains a list it is added to
5549 	     * list_stack. */
5550 	    todo = (int)cur_ht->ht_used;
5551 	    for (hi = cur_ht->ht_array; todo > 0; ++hi)
5552 		if (!HASHITEM_EMPTY(hi))
5553 		{
5554 		    --todo;
5555 		    abort = abort || set_ref_in_item(&HI2DI(hi)->di_tv, copyID,
5556 						       &ht_stack, list_stack);
5557 		}
5558 	}
5559 
5560 	if (ht_stack == NULL)
5561 	    break;
5562 
5563 	/* take an item from the stack */
5564 	cur_ht = ht_stack->ht;
5565 	tempitem = ht_stack;
5566 	ht_stack = ht_stack->prev;
5567 	free(tempitem);
5568     }
5569 
5570     return abort;
5571 }
5572 
5573 /*
5574  * Mark all lists and dicts referenced through list "l" with "copyID".
5575  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
5576  *
5577  * Returns TRUE if setting references failed somehow.
5578  */
5579     int
5580 set_ref_in_list(list_T *l, int copyID, ht_stack_T **ht_stack)
5581 {
5582     listitem_T	 *li;
5583     int		 abort = FALSE;
5584     list_T	 *cur_l;
5585     list_stack_T *list_stack = NULL;
5586     list_stack_T *tempitem;
5587 
5588     cur_l = l;
5589     for (;;)
5590     {
5591 	if (!abort)
5592 	    /* Mark each item in the list.  If the item contains a hashtab
5593 	     * it is added to ht_stack, if it contains a list it is added to
5594 	     * list_stack. */
5595 	    for (li = cur_l->lv_first; !abort && li != NULL; li = li->li_next)
5596 		abort = abort || set_ref_in_item(&li->li_tv, copyID,
5597 						       ht_stack, &list_stack);
5598 	if (list_stack == NULL)
5599 	    break;
5600 
5601 	/* take an item from the stack */
5602 	cur_l = list_stack->list;
5603 	tempitem = list_stack;
5604 	list_stack = list_stack->prev;
5605 	free(tempitem);
5606     }
5607 
5608     return abort;
5609 }
5610 
5611 /*
5612  * Mark all lists and dicts referenced through typval "tv" with "copyID".
5613  * "list_stack" is used to add lists to be marked.  Can be NULL.
5614  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
5615  *
5616  * Returns TRUE if setting references failed somehow.
5617  */
5618     int
5619 set_ref_in_item(
5620     typval_T	    *tv,
5621     int		    copyID,
5622     ht_stack_T	    **ht_stack,
5623     list_stack_T    **list_stack)
5624 {
5625     int		abort = FALSE;
5626 
5627     if (tv->v_type == VAR_DICT)
5628     {
5629 	dict_T	*dd = tv->vval.v_dict;
5630 
5631 	if (dd != NULL && dd->dv_copyID != copyID)
5632 	{
5633 	    /* Didn't see this dict yet. */
5634 	    dd->dv_copyID = copyID;
5635 	    if (ht_stack == NULL)
5636 	    {
5637 		abort = set_ref_in_ht(&dd->dv_hashtab, copyID, list_stack);
5638 	    }
5639 	    else
5640 	    {
5641 		ht_stack_T *newitem = (ht_stack_T*)malloc(sizeof(ht_stack_T));
5642 		if (newitem == NULL)
5643 		    abort = TRUE;
5644 		else
5645 		{
5646 		    newitem->ht = &dd->dv_hashtab;
5647 		    newitem->prev = *ht_stack;
5648 		    *ht_stack = newitem;
5649 		}
5650 	    }
5651 	}
5652     }
5653     else if (tv->v_type == VAR_LIST)
5654     {
5655 	list_T	*ll = tv->vval.v_list;
5656 
5657 	if (ll != NULL && ll->lv_copyID != copyID)
5658 	{
5659 	    /* Didn't see this list yet. */
5660 	    ll->lv_copyID = copyID;
5661 	    if (list_stack == NULL)
5662 	    {
5663 		abort = set_ref_in_list(ll, copyID, ht_stack);
5664 	    }
5665 	    else
5666 	    {
5667 		list_stack_T *newitem = (list_stack_T*)malloc(
5668 							sizeof(list_stack_T));
5669 		if (newitem == NULL)
5670 		    abort = TRUE;
5671 		else
5672 		{
5673 		    newitem->list = ll;
5674 		    newitem->prev = *list_stack;
5675 		    *list_stack = newitem;
5676 		}
5677 	    }
5678 	}
5679     }
5680     else if (tv->v_type == VAR_FUNC)
5681     {
5682 	abort = set_ref_in_func(tv->vval.v_string, NULL, copyID);
5683     }
5684     else if (tv->v_type == VAR_PARTIAL)
5685     {
5686 	partial_T	*pt = tv->vval.v_partial;
5687 	int		i;
5688 
5689 	/* A partial does not have a copyID, because it cannot contain itself.
5690 	 */
5691 	if (pt != NULL)
5692 	{
5693 	    abort = set_ref_in_func(pt->pt_name, pt->pt_func, copyID);
5694 
5695 	    if (pt->pt_dict != NULL)
5696 	    {
5697 		typval_T dtv;
5698 
5699 		dtv.v_type = VAR_DICT;
5700 		dtv.vval.v_dict = pt->pt_dict;
5701 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5702 	    }
5703 
5704 	    for (i = 0; i < pt->pt_argc; ++i)
5705 		abort = abort || set_ref_in_item(&pt->pt_argv[i], copyID,
5706 							ht_stack, list_stack);
5707 	}
5708     }
5709 #ifdef FEAT_JOB_CHANNEL
5710     else if (tv->v_type == VAR_JOB)
5711     {
5712 	job_T	    *job = tv->vval.v_job;
5713 	typval_T    dtv;
5714 
5715 	if (job != NULL && job->jv_copyID != copyID)
5716 	{
5717 	    job->jv_copyID = copyID;
5718 	    if (job->jv_channel != NULL)
5719 	    {
5720 		dtv.v_type = VAR_CHANNEL;
5721 		dtv.vval.v_channel = job->jv_channel;
5722 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5723 	    }
5724 	    if (job->jv_exit_partial != NULL)
5725 	    {
5726 		dtv.v_type = VAR_PARTIAL;
5727 		dtv.vval.v_partial = job->jv_exit_partial;
5728 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5729 	    }
5730 	}
5731     }
5732     else if (tv->v_type == VAR_CHANNEL)
5733     {
5734 	channel_T   *ch =tv->vval.v_channel;
5735 	ch_part_T   part;
5736 	typval_T    dtv;
5737 	jsonq_T	    *jq;
5738 	cbq_T	    *cq;
5739 
5740 	if (ch != NULL && ch->ch_copyID != copyID)
5741 	{
5742 	    ch->ch_copyID = copyID;
5743 	    for (part = PART_SOCK; part < PART_COUNT; ++part)
5744 	    {
5745 		for (jq = ch->ch_part[part].ch_json_head.jq_next; jq != NULL;
5746 							     jq = jq->jq_next)
5747 		    set_ref_in_item(jq->jq_value, copyID, ht_stack, list_stack);
5748 		for (cq = ch->ch_part[part].ch_cb_head.cq_next; cq != NULL;
5749 							     cq = cq->cq_next)
5750 		    if (cq->cq_partial != NULL)
5751 		    {
5752 			dtv.v_type = VAR_PARTIAL;
5753 			dtv.vval.v_partial = cq->cq_partial;
5754 			set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5755 		    }
5756 		if (ch->ch_part[part].ch_partial != NULL)
5757 		{
5758 		    dtv.v_type = VAR_PARTIAL;
5759 		    dtv.vval.v_partial = ch->ch_part[part].ch_partial;
5760 		    set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5761 		}
5762 	    }
5763 	    if (ch->ch_partial != NULL)
5764 	    {
5765 		dtv.v_type = VAR_PARTIAL;
5766 		dtv.vval.v_partial = ch->ch_partial;
5767 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5768 	    }
5769 	    if (ch->ch_close_partial != NULL)
5770 	    {
5771 		dtv.v_type = VAR_PARTIAL;
5772 		dtv.vval.v_partial = ch->ch_close_partial;
5773 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5774 	    }
5775 	}
5776     }
5777 #endif
5778     return abort;
5779 }
5780 
5781     static char *
5782 get_var_special_name(int nr)
5783 {
5784     switch (nr)
5785     {
5786 	case VVAL_FALSE: return "v:false";
5787 	case VVAL_TRUE:  return "v:true";
5788 	case VVAL_NONE:  return "v:none";
5789 	case VVAL_NULL:  return "v:null";
5790     }
5791     internal_error("get_var_special_name()");
5792     return "42";
5793 }
5794 
5795 /*
5796  * Return a string with the string representation of a variable.
5797  * If the memory is allocated "tofree" is set to it, otherwise NULL.
5798  * "numbuf" is used for a number.
5799  * When "copyID" is not NULL replace recursive lists and dicts with "...".
5800  * When both "echo_style" and "composite_val" are FALSE, put quotes around
5801  * stings as "string()", otherwise does not put quotes around strings, as
5802  * ":echo" displays values.
5803  * When "restore_copyID" is FALSE, repeated items in dictionaries and lists
5804  * are replaced with "...".
5805  * May return NULL.
5806  */
5807     char_u *
5808 echo_string_core(
5809     typval_T	*tv,
5810     char_u	**tofree,
5811     char_u	*numbuf,
5812     int		copyID,
5813     int		echo_style,
5814     int		restore_copyID,
5815     int		composite_val)
5816 {
5817     static int	recurse = 0;
5818     char_u	*r = NULL;
5819 
5820     if (recurse >= DICT_MAXNEST)
5821     {
5822 	if (!did_echo_string_emsg)
5823 	{
5824 	    /* Only give this message once for a recursive call to avoid
5825 	     * flooding the user with errors.  And stop iterating over lists
5826 	     * and dicts. */
5827 	    did_echo_string_emsg = TRUE;
5828 	    emsg(_("E724: variable nested too deep for displaying"));
5829 	}
5830 	*tofree = NULL;
5831 	return (char_u *)"{E724}";
5832     }
5833     ++recurse;
5834 
5835     switch (tv->v_type)
5836     {
5837 	case VAR_STRING:
5838 	    if (echo_style && !composite_val)
5839 	    {
5840 		*tofree = NULL;
5841 		r = tv->vval.v_string;
5842 		if (r == NULL)
5843 		    r = (char_u *)"";
5844 	    }
5845 	    else
5846 	    {
5847 		*tofree = string_quote(tv->vval.v_string, FALSE);
5848 		r = *tofree;
5849 	    }
5850 	    break;
5851 
5852 	case VAR_FUNC:
5853 	    if (echo_style)
5854 	    {
5855 		*tofree = NULL;
5856 		r = tv->vval.v_string;
5857 	    }
5858 	    else
5859 	    {
5860 		*tofree = string_quote(tv->vval.v_string, TRUE);
5861 		r = *tofree;
5862 	    }
5863 	    break;
5864 
5865 	case VAR_PARTIAL:
5866 	    {
5867 		partial_T   *pt = tv->vval.v_partial;
5868 		char_u	    *fname = string_quote(pt == NULL ? NULL
5869 						    : partial_name(pt), FALSE);
5870 		garray_T    ga;
5871 		int	    i;
5872 		char_u	    *tf;
5873 
5874 		ga_init2(&ga, 1, 100);
5875 		ga_concat(&ga, (char_u *)"function(");
5876 		if (fname != NULL)
5877 		{
5878 		    ga_concat(&ga, fname);
5879 		    vim_free(fname);
5880 		}
5881 		if (pt != NULL && pt->pt_argc > 0)
5882 		{
5883 		    ga_concat(&ga, (char_u *)", [");
5884 		    for (i = 0; i < pt->pt_argc; ++i)
5885 		    {
5886 			if (i > 0)
5887 			    ga_concat(&ga, (char_u *)", ");
5888 			ga_concat(&ga,
5889 			     tv2string(&pt->pt_argv[i], &tf, numbuf, copyID));
5890 			vim_free(tf);
5891 		    }
5892 		    ga_concat(&ga, (char_u *)"]");
5893 		}
5894 		if (pt != NULL && pt->pt_dict != NULL)
5895 		{
5896 		    typval_T dtv;
5897 
5898 		    ga_concat(&ga, (char_u *)", ");
5899 		    dtv.v_type = VAR_DICT;
5900 		    dtv.vval.v_dict = pt->pt_dict;
5901 		    ga_concat(&ga, tv2string(&dtv, &tf, numbuf, copyID));
5902 		    vim_free(tf);
5903 		}
5904 		ga_concat(&ga, (char_u *)")");
5905 
5906 		*tofree = ga.ga_data;
5907 		r = *tofree;
5908 		break;
5909 	    }
5910 
5911 	case VAR_BLOB:
5912 	    r = blob2string(tv->vval.v_blob, tofree, numbuf);
5913 	    break;
5914 
5915 	case VAR_LIST:
5916 	    if (tv->vval.v_list == NULL)
5917 	    {
5918 		*tofree = NULL;
5919 		r = NULL;
5920 	    }
5921 	    else if (copyID != 0 && tv->vval.v_list->lv_copyID == copyID
5922 		    && tv->vval.v_list->lv_len > 0)
5923 	    {
5924 		*tofree = NULL;
5925 		r = (char_u *)"[...]";
5926 	    }
5927 	    else
5928 	    {
5929 		int old_copyID = tv->vval.v_list->lv_copyID;
5930 
5931 		tv->vval.v_list->lv_copyID = copyID;
5932 		*tofree = list2string(tv, copyID, restore_copyID);
5933 		if (restore_copyID)
5934 		    tv->vval.v_list->lv_copyID = old_copyID;
5935 		r = *tofree;
5936 	    }
5937 	    break;
5938 
5939 	case VAR_DICT:
5940 	    if (tv->vval.v_dict == NULL)
5941 	    {
5942 		*tofree = NULL;
5943 		r = NULL;
5944 	    }
5945 	    else if (copyID != 0 && tv->vval.v_dict->dv_copyID == copyID
5946 		    && tv->vval.v_dict->dv_hashtab.ht_used != 0)
5947 	    {
5948 		*tofree = NULL;
5949 		r = (char_u *)"{...}";
5950 	    }
5951 	    else
5952 	    {
5953 		int old_copyID = tv->vval.v_dict->dv_copyID;
5954 		tv->vval.v_dict->dv_copyID = copyID;
5955 		*tofree = dict2string(tv, copyID, restore_copyID);
5956 		if (restore_copyID)
5957 		    tv->vval.v_dict->dv_copyID = old_copyID;
5958 		r = *tofree;
5959 	    }
5960 	    break;
5961 
5962 	case VAR_NUMBER:
5963 	case VAR_UNKNOWN:
5964 	    *tofree = NULL;
5965 	    r = tv_get_string_buf(tv, numbuf);
5966 	    break;
5967 
5968 	case VAR_JOB:
5969 	case VAR_CHANNEL:
5970 	    *tofree = NULL;
5971 	    r = tv_get_string_buf(tv, numbuf);
5972 	    if (composite_val)
5973 	    {
5974 		*tofree = string_quote(r, FALSE);
5975 		r = *tofree;
5976 	    }
5977 	    break;
5978 
5979 	case VAR_FLOAT:
5980 #ifdef FEAT_FLOAT
5981 	    *tofree = NULL;
5982 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv->vval.v_float);
5983 	    r = numbuf;
5984 	    break;
5985 #endif
5986 
5987 	case VAR_SPECIAL:
5988 	    *tofree = NULL;
5989 	    r = (char_u *)get_var_special_name(tv->vval.v_number);
5990 	    break;
5991     }
5992 
5993     if (--recurse == 0)
5994 	did_echo_string_emsg = FALSE;
5995     return r;
5996 }
5997 
5998 /*
5999  * Return a string with the string representation of a variable.
6000  * If the memory is allocated "tofree" is set to it, otherwise NULL.
6001  * "numbuf" is used for a number.
6002  * Does not put quotes around strings, as ":echo" displays values.
6003  * When "copyID" is not NULL replace recursive lists and dicts with "...".
6004  * May return NULL.
6005  */
6006     char_u *
6007 echo_string(
6008     typval_T	*tv,
6009     char_u	**tofree,
6010     char_u	*numbuf,
6011     int		copyID)
6012 {
6013     return echo_string_core(tv, tofree, numbuf, copyID, TRUE, FALSE, FALSE);
6014 }
6015 
6016 /*
6017  * Return a string with the string representation of a variable.
6018  * If the memory is allocated "tofree" is set to it, otherwise NULL.
6019  * "numbuf" is used for a number.
6020  * Puts quotes around strings, so that they can be parsed back by eval().
6021  * May return NULL.
6022  */
6023     char_u *
6024 tv2string(
6025     typval_T	*tv,
6026     char_u	**tofree,
6027     char_u	*numbuf,
6028     int		copyID)
6029 {
6030     return echo_string_core(tv, tofree, numbuf, copyID, FALSE, TRUE, FALSE);
6031 }
6032 
6033 /*
6034  * Return string "str" in ' quotes, doubling ' characters.
6035  * If "str" is NULL an empty string is assumed.
6036  * If "function" is TRUE make it function('string').
6037  */
6038     char_u *
6039 string_quote(char_u *str, int function)
6040 {
6041     unsigned	len;
6042     char_u	*p, *r, *s;
6043 
6044     len = (function ? 13 : 3);
6045     if (str != NULL)
6046     {
6047 	len += (unsigned)STRLEN(str);
6048 	for (p = str; *p != NUL; MB_PTR_ADV(p))
6049 	    if (*p == '\'')
6050 		++len;
6051     }
6052     s = r = alloc(len);
6053     if (r != NULL)
6054     {
6055 	if (function)
6056 	{
6057 	    STRCPY(r, "function('");
6058 	    r += 10;
6059 	}
6060 	else
6061 	    *r++ = '\'';
6062 	if (str != NULL)
6063 	    for (p = str; *p != NUL; )
6064 	    {
6065 		if (*p == '\'')
6066 		    *r++ = '\'';
6067 		MB_COPY_CHAR(p, r);
6068 	    }
6069 	*r++ = '\'';
6070 	if (function)
6071 	    *r++ = ')';
6072 	*r++ = NUL;
6073     }
6074     return s;
6075 }
6076 
6077 #if defined(FEAT_FLOAT) || defined(PROTO)
6078 /*
6079  * Convert the string "text" to a floating point number.
6080  * This uses strtod().  setlocale(LC_NUMERIC, "C") has been used to make sure
6081  * this always uses a decimal point.
6082  * Returns the length of the text that was consumed.
6083  */
6084     int
6085 string2float(
6086     char_u	*text,
6087     float_T	*value)	    /* result stored here */
6088 {
6089     char	*s = (char *)text;
6090     float_T	f;
6091 
6092     /* MS-Windows does not deal with "inf" and "nan" properly. */
6093     if (STRNICMP(text, "inf", 3) == 0)
6094     {
6095 	*value = INFINITY;
6096 	return 3;
6097     }
6098     if (STRNICMP(text, "-inf", 3) == 0)
6099     {
6100 	*value = -INFINITY;
6101 	return 4;
6102     }
6103     if (STRNICMP(text, "nan", 3) == 0)
6104     {
6105 	*value = NAN;
6106 	return 3;
6107     }
6108     f = strtod(s, &s);
6109     *value = f;
6110     return (int)((char_u *)s - text);
6111 }
6112 #endif
6113 
6114 /*
6115  * Get the value of an environment variable.
6116  * "arg" is pointing to the '$'.  It is advanced to after the name.
6117  * If the environment variable was not set, silently assume it is empty.
6118  * Return FAIL if the name is invalid.
6119  */
6120     static int
6121 get_env_tv(char_u **arg, typval_T *rettv, int evaluate)
6122 {
6123     char_u	*string = NULL;
6124     int		len;
6125     int		cc;
6126     char_u	*name;
6127     int		mustfree = FALSE;
6128 
6129     ++*arg;
6130     name = *arg;
6131     len = get_env_len(arg);
6132     if (evaluate)
6133     {
6134 	if (len == 0)
6135 	    return FAIL; /* invalid empty name */
6136 
6137 	cc = name[len];
6138 	name[len] = NUL;
6139 	/* first try vim_getenv(), fast for normal environment vars */
6140 	string = vim_getenv(name, &mustfree);
6141 	if (string != NULL && *string != NUL)
6142 	{
6143 	    if (!mustfree)
6144 		string = vim_strsave(string);
6145 	}
6146 	else
6147 	{
6148 	    if (mustfree)
6149 		vim_free(string);
6150 
6151 	    /* next try expanding things like $VIM and ${HOME} */
6152 	    string = expand_env_save(name - 1);
6153 	    if (string != NULL && *string == '$')
6154 		VIM_CLEAR(string);
6155 	}
6156 	name[len] = cc;
6157 
6158 	rettv->v_type = VAR_STRING;
6159 	rettv->vval.v_string = string;
6160     }
6161 
6162     return OK;
6163 }
6164 
6165 
6166 
6167 /*
6168  * Translate a String variable into a position.
6169  * Returns NULL when there is an error.
6170  */
6171     pos_T *
6172 var2fpos(
6173     typval_T	*varp,
6174     int		dollar_lnum,	/* TRUE when $ is last line */
6175     int		*fnum)		/* set to fnum for '0, 'A, etc. */
6176 {
6177     char_u		*name;
6178     static pos_T	pos;
6179     pos_T		*pp;
6180 
6181     /* Argument can be [lnum, col, coladd]. */
6182     if (varp->v_type == VAR_LIST)
6183     {
6184 	list_T		*l;
6185 	int		len;
6186 	int		error = FALSE;
6187 	listitem_T	*li;
6188 
6189 	l = varp->vval.v_list;
6190 	if (l == NULL)
6191 	    return NULL;
6192 
6193 	/* Get the line number */
6194 	pos.lnum = list_find_nr(l, 0L, &error);
6195 	if (error || pos.lnum <= 0 || pos.lnum > curbuf->b_ml.ml_line_count)
6196 	    return NULL;	/* invalid line number */
6197 
6198 	/* Get the column number */
6199 	pos.col = list_find_nr(l, 1L, &error);
6200 	if (error)
6201 	    return NULL;
6202 	len = (long)STRLEN(ml_get(pos.lnum));
6203 
6204 	/* We accept "$" for the column number: last column. */
6205 	li = list_find(l, 1L);
6206 	if (li != NULL && li->li_tv.v_type == VAR_STRING
6207 		&& li->li_tv.vval.v_string != NULL
6208 		&& STRCMP(li->li_tv.vval.v_string, "$") == 0)
6209 	    pos.col = len + 1;
6210 
6211 	/* Accept a position up to the NUL after the line. */
6212 	if (pos.col == 0 || (int)pos.col > len + 1)
6213 	    return NULL;	/* invalid column number */
6214 	--pos.col;
6215 
6216 #ifdef FEAT_VIRTUALEDIT
6217 	/* Get the virtual offset.  Defaults to zero. */
6218 	pos.coladd = list_find_nr(l, 2L, &error);
6219 	if (error)
6220 	    pos.coladd = 0;
6221 #endif
6222 
6223 	return &pos;
6224     }
6225 
6226     name = tv_get_string_chk(varp);
6227     if (name == NULL)
6228 	return NULL;
6229     if (name[0] == '.')				/* cursor */
6230 	return &curwin->w_cursor;
6231     if (name[0] == 'v' && name[1] == NUL)	/* Visual start */
6232     {
6233 	if (VIsual_active)
6234 	    return &VIsual;
6235 	return &curwin->w_cursor;
6236     }
6237     if (name[0] == '\'')			/* mark */
6238     {
6239 	pp = getmark_buf_fnum(curbuf, name[1], FALSE, fnum);
6240 	if (pp == NULL || pp == (pos_T *)-1 || pp->lnum <= 0)
6241 	    return NULL;
6242 	return pp;
6243     }
6244 
6245 #ifdef FEAT_VIRTUALEDIT
6246     pos.coladd = 0;
6247 #endif
6248 
6249     if (name[0] == 'w' && dollar_lnum)
6250     {
6251 	pos.col = 0;
6252 	if (name[1] == '0')		/* "w0": first visible line */
6253 	{
6254 	    update_topline();
6255 	    /* In silent Ex mode topline is zero, but that's not a valid line
6256 	     * number; use one instead. */
6257 	    pos.lnum = curwin->w_topline > 0 ? curwin->w_topline : 1;
6258 	    return &pos;
6259 	}
6260 	else if (name[1] == '$')	/* "w$": last visible line */
6261 	{
6262 	    validate_botline();
6263 	    /* In silent Ex mode botline is zero, return zero then. */
6264 	    pos.lnum = curwin->w_botline > 0 ? curwin->w_botline - 1 : 0;
6265 	    return &pos;
6266 	}
6267     }
6268     else if (name[0] == '$')		/* last column or line */
6269     {
6270 	if (dollar_lnum)
6271 	{
6272 	    pos.lnum = curbuf->b_ml.ml_line_count;
6273 	    pos.col = 0;
6274 	}
6275 	else
6276 	{
6277 	    pos.lnum = curwin->w_cursor.lnum;
6278 	    pos.col = (colnr_T)STRLEN(ml_get_curline());
6279 	}
6280 	return &pos;
6281     }
6282     return NULL;
6283 }
6284 
6285 /*
6286  * Convert list in "arg" into a position and optional file number.
6287  * When "fnump" is NULL there is no file number, only 3 items.
6288  * Note that the column is passed on as-is, the caller may want to decrement
6289  * it to use 1 for the first column.
6290  * Return FAIL when conversion is not possible, doesn't check the position for
6291  * validity.
6292  */
6293     int
6294 list2fpos(
6295     typval_T	*arg,
6296     pos_T	*posp,
6297     int		*fnump,
6298     colnr_T	*curswantp)
6299 {
6300     list_T	*l = arg->vval.v_list;
6301     long	i = 0;
6302     long	n;
6303 
6304     /* List must be: [fnum, lnum, col, coladd, curswant], where "fnum" is only
6305      * there when "fnump" isn't NULL; "coladd" and "curswant" are optional. */
6306     if (arg->v_type != VAR_LIST
6307 	    || l == NULL
6308 	    || l->lv_len < (fnump == NULL ? 2 : 3)
6309 	    || l->lv_len > (fnump == NULL ? 4 : 5))
6310 	return FAIL;
6311 
6312     if (fnump != NULL)
6313     {
6314 	n = list_find_nr(l, i++, NULL);	/* fnum */
6315 	if (n < 0)
6316 	    return FAIL;
6317 	if (n == 0)
6318 	    n = curbuf->b_fnum;		/* current buffer */
6319 	*fnump = n;
6320     }
6321 
6322     n = list_find_nr(l, i++, NULL);	/* lnum */
6323     if (n < 0)
6324 	return FAIL;
6325     posp->lnum = n;
6326 
6327     n = list_find_nr(l, i++, NULL);	/* col */
6328     if (n < 0)
6329 	return FAIL;
6330     posp->col = n;
6331 
6332 #ifdef FEAT_VIRTUALEDIT
6333     n = list_find_nr(l, i, NULL);	/* off */
6334     if (n < 0)
6335 	posp->coladd = 0;
6336     else
6337 	posp->coladd = n;
6338 #endif
6339 
6340     if (curswantp != NULL)
6341 	*curswantp = list_find_nr(l, i + 1, NULL);  /* curswant */
6342 
6343     return OK;
6344 }
6345 
6346 /*
6347  * Get the length of an environment variable name.
6348  * Advance "arg" to the first character after the name.
6349  * Return 0 for error.
6350  */
6351     static int
6352 get_env_len(char_u **arg)
6353 {
6354     char_u	*p;
6355     int		len;
6356 
6357     for (p = *arg; vim_isIDc(*p); ++p)
6358 	;
6359     if (p == *arg)	    /* no name found */
6360 	return 0;
6361 
6362     len = (int)(p - *arg);
6363     *arg = p;
6364     return len;
6365 }
6366 
6367 /*
6368  * Get the length of the name of a function or internal variable.
6369  * "arg" is advanced to the first non-white character after the name.
6370  * Return 0 if something is wrong.
6371  */
6372     int
6373 get_id_len(char_u **arg)
6374 {
6375     char_u	*p;
6376     int		len;
6377 
6378     /* Find the end of the name. */
6379     for (p = *arg; eval_isnamec(*p); ++p)
6380     {
6381 	if (*p == ':')
6382 	{
6383 	    /* "s:" is start of "s:var", but "n:" is not and can be used in
6384 	     * slice "[n:]".  Also "xx:" is not a namespace. */
6385 	    len = (int)(p - *arg);
6386 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, **arg) == NULL)
6387 		    || len > 1)
6388 		break;
6389 	}
6390     }
6391     if (p == *arg)	    /* no name found */
6392 	return 0;
6393 
6394     len = (int)(p - *arg);
6395     *arg = skipwhite(p);
6396 
6397     return len;
6398 }
6399 
6400 /*
6401  * Get the length of the name of a variable or function.
6402  * Only the name is recognized, does not handle ".key" or "[idx]".
6403  * "arg" is advanced to the first non-white character after the name.
6404  * Return -1 if curly braces expansion failed.
6405  * Return 0 if something else is wrong.
6406  * If the name contains 'magic' {}'s, expand them and return the
6407  * expanded name in an allocated string via 'alias' - caller must free.
6408  */
6409     int
6410 get_name_len(
6411     char_u	**arg,
6412     char_u	**alias,
6413     int		evaluate,
6414     int		verbose)
6415 {
6416     int		len;
6417     char_u	*p;
6418     char_u	*expr_start;
6419     char_u	*expr_end;
6420 
6421     *alias = NULL;  /* default to no alias */
6422 
6423     if ((*arg)[0] == K_SPECIAL && (*arg)[1] == KS_EXTRA
6424 						  && (*arg)[2] == (int)KE_SNR)
6425     {
6426 	/* hard coded <SNR>, already translated */
6427 	*arg += 3;
6428 	return get_id_len(arg) + 3;
6429     }
6430     len = eval_fname_script(*arg);
6431     if (len > 0)
6432     {
6433 	/* literal "<SID>", "s:" or "<SNR>" */
6434 	*arg += len;
6435     }
6436 
6437     /*
6438      * Find the end of the name; check for {} construction.
6439      */
6440     p = find_name_end(*arg, &expr_start, &expr_end,
6441 					       len > 0 ? 0 : FNE_CHECK_START);
6442     if (expr_start != NULL)
6443     {
6444 	char_u	*temp_string;
6445 
6446 	if (!evaluate)
6447 	{
6448 	    len += (int)(p - *arg);
6449 	    *arg = skipwhite(p);
6450 	    return len;
6451 	}
6452 
6453 	/*
6454 	 * Include any <SID> etc in the expanded string:
6455 	 * Thus the -len here.
6456 	 */
6457 	temp_string = make_expanded_name(*arg - len, expr_start, expr_end, p);
6458 	if (temp_string == NULL)
6459 	    return -1;
6460 	*alias = temp_string;
6461 	*arg = skipwhite(p);
6462 	return (int)STRLEN(temp_string);
6463     }
6464 
6465     len += get_id_len(arg);
6466     // Only give an error when there is something, otherwise it will be
6467     // reported at a higher level.
6468     if (len == 0 && verbose && **arg != NUL)
6469 	semsg(_(e_invexpr2), *arg);
6470 
6471     return len;
6472 }
6473 
6474 /*
6475  * Find the end of a variable or function name, taking care of magic braces.
6476  * If "expr_start" is not NULL then "expr_start" and "expr_end" are set to the
6477  * start and end of the first magic braces item.
6478  * "flags" can have FNE_INCL_BR and FNE_CHECK_START.
6479  * Return a pointer to just after the name.  Equal to "arg" if there is no
6480  * valid name.
6481  */
6482     char_u *
6483 find_name_end(
6484     char_u	*arg,
6485     char_u	**expr_start,
6486     char_u	**expr_end,
6487     int		flags)
6488 {
6489     int		mb_nest = 0;
6490     int		br_nest = 0;
6491     char_u	*p;
6492     int		len;
6493 
6494     if (expr_start != NULL)
6495     {
6496 	*expr_start = NULL;
6497 	*expr_end = NULL;
6498     }
6499 
6500     /* Quick check for valid starting character. */
6501     if ((flags & FNE_CHECK_START) && !eval_isnamec1(*arg) && *arg != '{')
6502 	return arg;
6503 
6504     for (p = arg; *p != NUL
6505 		    && (eval_isnamec(*p)
6506 			|| *p == '{'
6507 			|| ((flags & FNE_INCL_BR) && (*p == '[' || *p == '.'))
6508 			|| mb_nest != 0
6509 			|| br_nest != 0); MB_PTR_ADV(p))
6510     {
6511 	if (*p == '\'')
6512 	{
6513 	    /* skip over 'string' to avoid counting [ and ] inside it. */
6514 	    for (p = p + 1; *p != NUL && *p != '\''; MB_PTR_ADV(p))
6515 		;
6516 	    if (*p == NUL)
6517 		break;
6518 	}
6519 	else if (*p == '"')
6520 	{
6521 	    /* skip over "str\"ing" to avoid counting [ and ] inside it. */
6522 	    for (p = p + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
6523 		if (*p == '\\' && p[1] != NUL)
6524 		    ++p;
6525 	    if (*p == NUL)
6526 		break;
6527 	}
6528 	else if (br_nest == 0 && mb_nest == 0 && *p == ':')
6529 	{
6530 	    /* "s:" is start of "s:var", but "n:" is not and can be used in
6531 	     * slice "[n:]".  Also "xx:" is not a namespace. But {ns}: is. */
6532 	    len = (int)(p - arg);
6533 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, *arg) == NULL)
6534 		    || (len > 1 && p[-1] != '}'))
6535 		break;
6536 	}
6537 
6538 	if (mb_nest == 0)
6539 	{
6540 	    if (*p == '[')
6541 		++br_nest;
6542 	    else if (*p == ']')
6543 		--br_nest;
6544 	}
6545 
6546 	if (br_nest == 0)
6547 	{
6548 	    if (*p == '{')
6549 	    {
6550 		mb_nest++;
6551 		if (expr_start != NULL && *expr_start == NULL)
6552 		    *expr_start = p;
6553 	    }
6554 	    else if (*p == '}')
6555 	    {
6556 		mb_nest--;
6557 		if (expr_start != NULL && mb_nest == 0 && *expr_end == NULL)
6558 		    *expr_end = p;
6559 	    }
6560 	}
6561     }
6562 
6563     return p;
6564 }
6565 
6566 /*
6567  * Expands out the 'magic' {}'s in a variable/function name.
6568  * Note that this can call itself recursively, to deal with
6569  * constructs like foo{bar}{baz}{bam}
6570  * The four pointer arguments point to "foo{expre}ss{ion}bar"
6571  *			"in_start"      ^
6572  *			"expr_start"	   ^
6573  *			"expr_end"		 ^
6574  *			"in_end"			    ^
6575  *
6576  * Returns a new allocated string, which the caller must free.
6577  * Returns NULL for failure.
6578  */
6579     static char_u *
6580 make_expanded_name(
6581     char_u	*in_start,
6582     char_u	*expr_start,
6583     char_u	*expr_end,
6584     char_u	*in_end)
6585 {
6586     char_u	c1;
6587     char_u	*retval = NULL;
6588     char_u	*temp_result;
6589     char_u	*nextcmd = NULL;
6590 
6591     if (expr_end == NULL || in_end == NULL)
6592 	return NULL;
6593     *expr_start	= NUL;
6594     *expr_end = NUL;
6595     c1 = *in_end;
6596     *in_end = NUL;
6597 
6598     temp_result = eval_to_string(expr_start + 1, &nextcmd, FALSE);
6599     if (temp_result != NULL && nextcmd == NULL)
6600     {
6601 	retval = alloc((unsigned)(STRLEN(temp_result) + (expr_start - in_start)
6602 						   + (in_end - expr_end) + 1));
6603 	if (retval != NULL)
6604 	{
6605 	    STRCPY(retval, in_start);
6606 	    STRCAT(retval, temp_result);
6607 	    STRCAT(retval, expr_end + 1);
6608 	}
6609     }
6610     vim_free(temp_result);
6611 
6612     *in_end = c1;		/* put char back for error messages */
6613     *expr_start = '{';
6614     *expr_end = '}';
6615 
6616     if (retval != NULL)
6617     {
6618 	temp_result = find_name_end(retval, &expr_start, &expr_end, 0);
6619 	if (expr_start != NULL)
6620 	{
6621 	    /* Further expansion! */
6622 	    temp_result = make_expanded_name(retval, expr_start,
6623 						       expr_end, temp_result);
6624 	    vim_free(retval);
6625 	    retval = temp_result;
6626 	}
6627     }
6628 
6629     return retval;
6630 }
6631 
6632 /*
6633  * Return TRUE if character "c" can be used in a variable or function name.
6634  * Does not include '{' or '}' for magic braces.
6635  */
6636     int
6637 eval_isnamec(int c)
6638 {
6639     return (ASCII_ISALNUM(c) || c == '_' || c == ':' || c == AUTOLOAD_CHAR);
6640 }
6641 
6642 /*
6643  * Return TRUE if character "c" can be used as the first character in a
6644  * variable or function name (excluding '{' and '}').
6645  */
6646     int
6647 eval_isnamec1(int c)
6648 {
6649     return (ASCII_ISALPHA(c) || c == '_');
6650 }
6651 
6652 /*
6653  * Set number v: variable to "val".
6654  */
6655     void
6656 set_vim_var_nr(int idx, varnumber_T val)
6657 {
6658     vimvars[idx].vv_nr = val;
6659 }
6660 
6661 /*
6662  * Get number v: variable value.
6663  */
6664     varnumber_T
6665 get_vim_var_nr(int idx)
6666 {
6667     return vimvars[idx].vv_nr;
6668 }
6669 
6670 /*
6671  * Get string v: variable value.  Uses a static buffer, can only be used once.
6672  * If the String variable has never been set, return an empty string.
6673  * Never returns NULL;
6674  */
6675     char_u *
6676 get_vim_var_str(int idx)
6677 {
6678     return tv_get_string(&vimvars[idx].vv_tv);
6679 }
6680 
6681 /*
6682  * Get List v: variable value.  Caller must take care of reference count when
6683  * needed.
6684  */
6685     list_T *
6686 get_vim_var_list(int idx)
6687 {
6688     return vimvars[idx].vv_list;
6689 }
6690 
6691 /*
6692  * Get Dict v: variable value.  Caller must take care of reference count when
6693  * needed.
6694  */
6695     dict_T *
6696 get_vim_var_dict(int idx)
6697 {
6698     return vimvars[idx].vv_dict;
6699 }
6700 
6701 /*
6702  * Set v:char to character "c".
6703  */
6704     void
6705 set_vim_var_char(int c)
6706 {
6707     char_u	buf[MB_MAXBYTES + 1];
6708 
6709 #ifdef FEAT_MBYTE
6710     if (has_mbyte)
6711 	buf[(*mb_char2bytes)(c, buf)] = NUL;
6712     else
6713 #endif
6714     {
6715 	buf[0] = c;
6716 	buf[1] = NUL;
6717     }
6718     set_vim_var_string(VV_CHAR, buf, -1);
6719 }
6720 
6721 /*
6722  * Set v:count to "count" and v:count1 to "count1".
6723  * When "set_prevcount" is TRUE first set v:prevcount from v:count.
6724  */
6725     void
6726 set_vcount(
6727     long	count,
6728     long	count1,
6729     int		set_prevcount)
6730 {
6731     if (set_prevcount)
6732 	vimvars[VV_PREVCOUNT].vv_nr = vimvars[VV_COUNT].vv_nr;
6733     vimvars[VV_COUNT].vv_nr = count;
6734     vimvars[VV_COUNT1].vv_nr = count1;
6735 }
6736 
6737 /*
6738  * Save variables that might be changed as a side effect.  Used when executing
6739  * a timer callback.
6740  */
6741     void
6742 save_vimvars(vimvars_save_T *vvsave)
6743 {
6744     vvsave->vv_prevcount = vimvars[VV_PREVCOUNT].vv_nr;
6745     vvsave->vv_count = vimvars[VV_COUNT].vv_nr;
6746     vvsave->vv_count1 = vimvars[VV_COUNT1].vv_nr;
6747 }
6748 
6749 /*
6750  * Restore variables saved by save_vimvars().
6751  */
6752     void
6753 restore_vimvars(vimvars_save_T *vvsave)
6754 {
6755     vimvars[VV_PREVCOUNT].vv_nr = vvsave->vv_prevcount;
6756     vimvars[VV_COUNT].vv_nr = vvsave->vv_count;
6757     vimvars[VV_COUNT1].vv_nr = vvsave->vv_count1;
6758 }
6759 
6760 /*
6761  * Set string v: variable to a copy of "val".
6762  */
6763     void
6764 set_vim_var_string(
6765     int		idx,
6766     char_u	*val,
6767     int		len)	    /* length of "val" to use or -1 (whole string) */
6768 {
6769     clear_tv(&vimvars[idx].vv_di.di_tv);
6770     vimvars[idx].vv_type = VAR_STRING;
6771     if (val == NULL)
6772 	vimvars[idx].vv_str = NULL;
6773     else if (len == -1)
6774 	vimvars[idx].vv_str = vim_strsave(val);
6775     else
6776 	vimvars[idx].vv_str = vim_strnsave(val, len);
6777 }
6778 
6779 /*
6780  * Set List v: variable to "val".
6781  */
6782     void
6783 set_vim_var_list(int idx, list_T *val)
6784 {
6785     clear_tv(&vimvars[idx].vv_di.di_tv);
6786     vimvars[idx].vv_type = VAR_LIST;
6787     vimvars[idx].vv_list = val;
6788     if (val != NULL)
6789 	++val->lv_refcount;
6790 }
6791 
6792 /*
6793  * Set Dictionary v: variable to "val".
6794  */
6795     void
6796 set_vim_var_dict(int idx, dict_T *val)
6797 {
6798     clear_tv(&vimvars[idx].vv_di.di_tv);
6799     vimvars[idx].vv_type = VAR_DICT;
6800     vimvars[idx].vv_dict = val;
6801     if (val != NULL)
6802     {
6803 	++val->dv_refcount;
6804 	dict_set_items_ro(val);
6805     }
6806 }
6807 
6808 /*
6809  * Set v:register if needed.
6810  */
6811     void
6812 set_reg_var(int c)
6813 {
6814     char_u	regname;
6815 
6816     if (c == 0 || c == ' ')
6817 	regname = '"';
6818     else
6819 	regname = c;
6820     /* Avoid free/alloc when the value is already right. */
6821     if (vimvars[VV_REG].vv_str == NULL || vimvars[VV_REG].vv_str[0] != c)
6822 	set_vim_var_string(VV_REG, &regname, 1);
6823 }
6824 
6825 /*
6826  * Get or set v:exception.  If "oldval" == NULL, return the current value.
6827  * Otherwise, restore the value to "oldval" and return NULL.
6828  * Must always be called in pairs to save and restore v:exception!  Does not
6829  * take care of memory allocations.
6830  */
6831     char_u *
6832 v_exception(char_u *oldval)
6833 {
6834     if (oldval == NULL)
6835 	return vimvars[VV_EXCEPTION].vv_str;
6836 
6837     vimvars[VV_EXCEPTION].vv_str = oldval;
6838     return NULL;
6839 }
6840 
6841 /*
6842  * Get or set v:throwpoint.  If "oldval" == NULL, return the current value.
6843  * Otherwise, restore the value to "oldval" and return NULL.
6844  * Must always be called in pairs to save and restore v:throwpoint!  Does not
6845  * take care of memory allocations.
6846  */
6847     char_u *
6848 v_throwpoint(char_u *oldval)
6849 {
6850     if (oldval == NULL)
6851 	return vimvars[VV_THROWPOINT].vv_str;
6852 
6853     vimvars[VV_THROWPOINT].vv_str = oldval;
6854     return NULL;
6855 }
6856 
6857 /*
6858  * Set v:cmdarg.
6859  * If "eap" != NULL, use "eap" to generate the value and return the old value.
6860  * If "oldarg" != NULL, restore the value to "oldarg" and return NULL.
6861  * Must always be called in pairs!
6862  */
6863     char_u *
6864 set_cmdarg(exarg_T *eap, char_u *oldarg)
6865 {
6866     char_u	*oldval;
6867     char_u	*newval;
6868     unsigned	len;
6869 
6870     oldval = vimvars[VV_CMDARG].vv_str;
6871     if (eap == NULL)
6872     {
6873 	vim_free(oldval);
6874 	vimvars[VV_CMDARG].vv_str = oldarg;
6875 	return NULL;
6876     }
6877 
6878     if (eap->force_bin == FORCE_BIN)
6879 	len = 6;
6880     else if (eap->force_bin == FORCE_NOBIN)
6881 	len = 8;
6882     else
6883 	len = 0;
6884 
6885     if (eap->read_edit)
6886 	len += 7;
6887 
6888     if (eap->force_ff != 0)
6889 	len += 10; /* " ++ff=unix" */
6890 # ifdef FEAT_MBYTE
6891     if (eap->force_enc != 0)
6892 	len += (unsigned)STRLEN(eap->cmd + eap->force_enc) + 7;
6893     if (eap->bad_char != 0)
6894 	len += 7 + 4;  /* " ++bad=" + "keep" or "drop" */
6895 # endif
6896 
6897     newval = alloc(len + 1);
6898     if (newval == NULL)
6899 	return NULL;
6900 
6901     if (eap->force_bin == FORCE_BIN)
6902 	sprintf((char *)newval, " ++bin");
6903     else if (eap->force_bin == FORCE_NOBIN)
6904 	sprintf((char *)newval, " ++nobin");
6905     else
6906 	*newval = NUL;
6907 
6908     if (eap->read_edit)
6909 	STRCAT(newval, " ++edit");
6910 
6911     if (eap->force_ff != 0)
6912 	sprintf((char *)newval + STRLEN(newval), " ++ff=%s",
6913 						eap->force_ff == 'u' ? "unix"
6914 						: eap->force_ff == 'd' ? "dos"
6915 						: "mac");
6916 #ifdef FEAT_MBYTE
6917     if (eap->force_enc != 0)
6918 	sprintf((char *)newval + STRLEN(newval), " ++enc=%s",
6919 					       eap->cmd + eap->force_enc);
6920     if (eap->bad_char == BAD_KEEP)
6921 	STRCPY(newval + STRLEN(newval), " ++bad=keep");
6922     else if (eap->bad_char == BAD_DROP)
6923 	STRCPY(newval + STRLEN(newval), " ++bad=drop");
6924     else if (eap->bad_char != 0)
6925 	sprintf((char *)newval + STRLEN(newval), " ++bad=%c", eap->bad_char);
6926 #endif
6927     vimvars[VV_CMDARG].vv_str = newval;
6928     return oldval;
6929 }
6930 
6931 /*
6932  * Get the value of internal variable "name".
6933  * Return OK or FAIL.  If OK is returned "rettv" must be cleared.
6934  */
6935     int
6936 get_var_tv(
6937     char_u	*name,
6938     int		len,		/* length of "name" */
6939     typval_T	*rettv,		/* NULL when only checking existence */
6940     dictitem_T	**dip,		/* non-NULL when typval's dict item is needed */
6941     int		verbose,	/* may give error message */
6942     int		no_autoload)	/* do not use script autoloading */
6943 {
6944     int		ret = OK;
6945     typval_T	*tv = NULL;
6946     dictitem_T	*v;
6947     int		cc;
6948 
6949     /* truncate the name, so that we can use strcmp() */
6950     cc = name[len];
6951     name[len] = NUL;
6952 
6953     /*
6954      * Check for user-defined variables.
6955      */
6956     v = find_var(name, NULL, no_autoload);
6957     if (v != NULL)
6958     {
6959 	tv = &v->di_tv;
6960 	if (dip != NULL)
6961 	    *dip = v;
6962     }
6963 
6964     if (tv == NULL)
6965     {
6966 	if (rettv != NULL && verbose)
6967 	    semsg(_(e_undefvar), name);
6968 	ret = FAIL;
6969     }
6970     else if (rettv != NULL)
6971 	copy_tv(tv, rettv);
6972 
6973     name[len] = cc;
6974 
6975     return ret;
6976 }
6977 
6978 /*
6979  * Check if variable "name[len]" is a local variable or an argument.
6980  * If so, "*eval_lavars_used" is set to TRUE.
6981  */
6982     static void
6983 check_vars(char_u *name, int len)
6984 {
6985     int		cc;
6986     char_u	*varname;
6987     hashtab_T	*ht;
6988 
6989     if (eval_lavars_used == NULL)
6990 	return;
6991 
6992     /* truncate the name, so that we can use strcmp() */
6993     cc = name[len];
6994     name[len] = NUL;
6995 
6996     ht = find_var_ht(name, &varname);
6997     if (ht == get_funccal_local_ht() || ht == get_funccal_args_ht())
6998     {
6999 	if (find_var(name, NULL, TRUE) != NULL)
7000 	    *eval_lavars_used = TRUE;
7001     }
7002 
7003     name[len] = cc;
7004 }
7005 
7006 /*
7007  * Handle expr[expr], expr[expr:expr] subscript and .name lookup.
7008  * Also handle function call with Funcref variable: func(expr)
7009  * Can all be combined: dict.func(expr)[idx]['func'](expr)
7010  */
7011     int
7012 handle_subscript(
7013     char_u	**arg,
7014     typval_T	*rettv,
7015     int		evaluate,	/* do more than finding the end */
7016     int		verbose)	/* give error messages */
7017 {
7018     int		ret = OK;
7019     dict_T	*selfdict = NULL;
7020     char_u	*s;
7021     int		len;
7022     typval_T	functv;
7023 
7024     while (ret == OK
7025 	    && (**arg == '['
7026 		|| (**arg == '.' && rettv->v_type == VAR_DICT)
7027 		|| (**arg == '(' && (!evaluate || rettv->v_type == VAR_FUNC
7028 					    || rettv->v_type == VAR_PARTIAL)))
7029 	    && !VIM_ISWHITE(*(*arg - 1)))
7030     {
7031 	if (**arg == '(')
7032 	{
7033 	    partial_T	*pt = NULL;
7034 
7035 	    /* need to copy the funcref so that we can clear rettv */
7036 	    if (evaluate)
7037 	    {
7038 		functv = *rettv;
7039 		rettv->v_type = VAR_UNKNOWN;
7040 
7041 		/* Invoke the function.  Recursive! */
7042 		if (functv.v_type == VAR_PARTIAL)
7043 		{
7044 		    pt = functv.vval.v_partial;
7045 		    s = partial_name(pt);
7046 		}
7047 		else
7048 		    s = functv.vval.v_string;
7049 	    }
7050 	    else
7051 		s = (char_u *)"";
7052 	    ret = get_func_tv(s, (int)STRLEN(s), rettv, arg,
7053 			curwin->w_cursor.lnum, curwin->w_cursor.lnum,
7054 			&len, evaluate, pt, selfdict);
7055 
7056 	    /* Clear the funcref afterwards, so that deleting it while
7057 	     * evaluating the arguments is possible (see test55). */
7058 	    if (evaluate)
7059 		clear_tv(&functv);
7060 
7061 	    /* Stop the expression evaluation when immediately aborting on
7062 	     * error, or when an interrupt occurred or an exception was thrown
7063 	     * but not caught. */
7064 	    if (aborting())
7065 	    {
7066 		if (ret == OK)
7067 		    clear_tv(rettv);
7068 		ret = FAIL;
7069 	    }
7070 	    dict_unref(selfdict);
7071 	    selfdict = NULL;
7072 	}
7073 	else /* **arg == '[' || **arg == '.' */
7074 	{
7075 	    dict_unref(selfdict);
7076 	    if (rettv->v_type == VAR_DICT)
7077 	    {
7078 		selfdict = rettv->vval.v_dict;
7079 		if (selfdict != NULL)
7080 		    ++selfdict->dv_refcount;
7081 	    }
7082 	    else
7083 		selfdict = NULL;
7084 	    if (eval_index(arg, rettv, evaluate, verbose) == FAIL)
7085 	    {
7086 		clear_tv(rettv);
7087 		ret = FAIL;
7088 	    }
7089 	}
7090     }
7091 
7092     /* Turn "dict.Func" into a partial for "Func" bound to "dict".
7093      * Don't do this when "Func" is already a partial that was bound
7094      * explicitly (pt_auto is FALSE). */
7095     if (selfdict != NULL
7096 	    && (rettv->v_type == VAR_FUNC
7097 		|| (rettv->v_type == VAR_PARTIAL
7098 		    && (rettv->vval.v_partial->pt_auto
7099 			|| rettv->vval.v_partial->pt_dict == NULL))))
7100 	selfdict = make_partial(selfdict, rettv);
7101 
7102     dict_unref(selfdict);
7103     return ret;
7104 }
7105 
7106 /*
7107  * Allocate memory for a variable type-value, and make it empty (0 or NULL
7108  * value).
7109  */
7110     typval_T *
7111 alloc_tv(void)
7112 {
7113     return (typval_T *)alloc_clear((unsigned)sizeof(typval_T));
7114 }
7115 
7116 /*
7117  * Allocate memory for a variable type-value, and assign a string to it.
7118  * The string "s" must have been allocated, it is consumed.
7119  * Return NULL for out of memory, the variable otherwise.
7120  */
7121     static typval_T *
7122 alloc_string_tv(char_u *s)
7123 {
7124     typval_T	*rettv;
7125 
7126     rettv = alloc_tv();
7127     if (rettv != NULL)
7128     {
7129 	rettv->v_type = VAR_STRING;
7130 	rettv->vval.v_string = s;
7131     }
7132     else
7133 	vim_free(s);
7134     return rettv;
7135 }
7136 
7137 /*
7138  * Free the memory for a variable type-value.
7139  */
7140     void
7141 free_tv(typval_T *varp)
7142 {
7143     if (varp != NULL)
7144     {
7145 	switch (varp->v_type)
7146 	{
7147 	    case VAR_FUNC:
7148 		func_unref(varp->vval.v_string);
7149 		/* FALLTHROUGH */
7150 	    case VAR_STRING:
7151 		vim_free(varp->vval.v_string);
7152 		break;
7153 	    case VAR_PARTIAL:
7154 		partial_unref(varp->vval.v_partial);
7155 		break;
7156 	    case VAR_BLOB:
7157 		blob_unref(varp->vval.v_blob);
7158 		break;
7159 	    case VAR_LIST:
7160 		list_unref(varp->vval.v_list);
7161 		break;
7162 	    case VAR_DICT:
7163 		dict_unref(varp->vval.v_dict);
7164 		break;
7165 	    case VAR_JOB:
7166 #ifdef FEAT_JOB_CHANNEL
7167 		job_unref(varp->vval.v_job);
7168 		break;
7169 #endif
7170 	    case VAR_CHANNEL:
7171 #ifdef FEAT_JOB_CHANNEL
7172 		channel_unref(varp->vval.v_channel);
7173 		break;
7174 #endif
7175 	    case VAR_NUMBER:
7176 	    case VAR_FLOAT:
7177 	    case VAR_UNKNOWN:
7178 	    case VAR_SPECIAL:
7179 		break;
7180 	}
7181 	vim_free(varp);
7182     }
7183 }
7184 
7185 /*
7186  * Free the memory for a variable value and set the value to NULL or 0.
7187  */
7188     void
7189 clear_tv(typval_T *varp)
7190 {
7191     if (varp != NULL)
7192     {
7193 	switch (varp->v_type)
7194 	{
7195 	    case VAR_FUNC:
7196 		func_unref(varp->vval.v_string);
7197 		/* FALLTHROUGH */
7198 	    case VAR_STRING:
7199 		VIM_CLEAR(varp->vval.v_string);
7200 		break;
7201 	    case VAR_PARTIAL:
7202 		partial_unref(varp->vval.v_partial);
7203 		varp->vval.v_partial = NULL;
7204 		break;
7205 	    case VAR_BLOB:
7206 		blob_unref(varp->vval.v_blob);
7207 		varp->vval.v_blob = NULL;
7208 		break;
7209 	    case VAR_LIST:
7210 		list_unref(varp->vval.v_list);
7211 		varp->vval.v_list = NULL;
7212 		break;
7213 	    case VAR_DICT:
7214 		dict_unref(varp->vval.v_dict);
7215 		varp->vval.v_dict = NULL;
7216 		break;
7217 	    case VAR_NUMBER:
7218 	    case VAR_SPECIAL:
7219 		varp->vval.v_number = 0;
7220 		break;
7221 	    case VAR_FLOAT:
7222 #ifdef FEAT_FLOAT
7223 		varp->vval.v_float = 0.0;
7224 		break;
7225 #endif
7226 	    case VAR_JOB:
7227 #ifdef FEAT_JOB_CHANNEL
7228 		job_unref(varp->vval.v_job);
7229 		varp->vval.v_job = NULL;
7230 #endif
7231 		break;
7232 	    case VAR_CHANNEL:
7233 #ifdef FEAT_JOB_CHANNEL
7234 		channel_unref(varp->vval.v_channel);
7235 		varp->vval.v_channel = NULL;
7236 #endif
7237 	    case VAR_UNKNOWN:
7238 		break;
7239 	}
7240 	varp->v_lock = 0;
7241     }
7242 }
7243 
7244 /*
7245  * Set the value of a variable to NULL without freeing items.
7246  */
7247     void
7248 init_tv(typval_T *varp)
7249 {
7250     if (varp != NULL)
7251 	vim_memset(varp, 0, sizeof(typval_T));
7252 }
7253 
7254 /*
7255  * Get the number value of a variable.
7256  * If it is a String variable, uses vim_str2nr().
7257  * For incompatible types, return 0.
7258  * tv_get_number_chk() is similar to tv_get_number(), but informs the
7259  * caller of incompatible types: it sets *denote to TRUE if "denote"
7260  * is not NULL or returns -1 otherwise.
7261  */
7262     varnumber_T
7263 tv_get_number(typval_T *varp)
7264 {
7265     int		error = FALSE;
7266 
7267     return tv_get_number_chk(varp, &error);	/* return 0L on error */
7268 }
7269 
7270     varnumber_T
7271 tv_get_number_chk(typval_T *varp, int *denote)
7272 {
7273     varnumber_T	n = 0L;
7274 
7275     switch (varp->v_type)
7276     {
7277 	case VAR_NUMBER:
7278 	    return varp->vval.v_number;
7279 	case VAR_FLOAT:
7280 #ifdef FEAT_FLOAT
7281 	    emsg(_("E805: Using a Float as a Number"));
7282 	    break;
7283 #endif
7284 	case VAR_FUNC:
7285 	case VAR_PARTIAL:
7286 	    emsg(_("E703: Using a Funcref as a Number"));
7287 	    break;
7288 	case VAR_STRING:
7289 	    if (varp->vval.v_string != NULL)
7290 		vim_str2nr(varp->vval.v_string, NULL, NULL,
7291 						    STR2NR_ALL, &n, NULL, 0);
7292 	    return n;
7293 	case VAR_LIST:
7294 	    emsg(_("E745: Using a List as a Number"));
7295 	    break;
7296 	case VAR_DICT:
7297 	    emsg(_("E728: Using a Dictionary as a Number"));
7298 	    break;
7299 	case VAR_SPECIAL:
7300 	    return varp->vval.v_number == VVAL_TRUE ? 1 : 0;
7301 	    break;
7302 	case VAR_JOB:
7303 #ifdef FEAT_JOB_CHANNEL
7304 	    emsg(_("E910: Using a Job as a Number"));
7305 	    break;
7306 #endif
7307 	case VAR_CHANNEL:
7308 #ifdef FEAT_JOB_CHANNEL
7309 	    emsg(_("E913: Using a Channel as a Number"));
7310 	    break;
7311 #endif
7312 	case VAR_BLOB:
7313 	    emsg(_("E974: Using a Blob as a Number"));
7314 	    break;
7315 	case VAR_UNKNOWN:
7316 	    internal_error("tv_get_number(UNKNOWN)");
7317 	    break;
7318     }
7319     if (denote == NULL)		/* useful for values that must be unsigned */
7320 	n = -1;
7321     else
7322 	*denote = TRUE;
7323     return n;
7324 }
7325 
7326 #ifdef FEAT_FLOAT
7327     float_T
7328 tv_get_float(typval_T *varp)
7329 {
7330     switch (varp->v_type)
7331     {
7332 	case VAR_NUMBER:
7333 	    return (float_T)(varp->vval.v_number);
7334 	case VAR_FLOAT:
7335 	    return varp->vval.v_float;
7336 	case VAR_FUNC:
7337 	case VAR_PARTIAL:
7338 	    emsg(_("E891: Using a Funcref as a Float"));
7339 	    break;
7340 	case VAR_STRING:
7341 	    emsg(_("E892: Using a String as a Float"));
7342 	    break;
7343 	case VAR_LIST:
7344 	    emsg(_("E893: Using a List as a Float"));
7345 	    break;
7346 	case VAR_DICT:
7347 	    emsg(_("E894: Using a Dictionary as a Float"));
7348 	    break;
7349 	case VAR_SPECIAL:
7350 	    emsg(_("E907: Using a special value as a Float"));
7351 	    break;
7352 	case VAR_JOB:
7353 # ifdef FEAT_JOB_CHANNEL
7354 	    emsg(_("E911: Using a Job as a Float"));
7355 	    break;
7356 # endif
7357 	case VAR_CHANNEL:
7358 # ifdef FEAT_JOB_CHANNEL
7359 	    emsg(_("E914: Using a Channel as a Float"));
7360 	    break;
7361 # endif
7362 	case VAR_BLOB:
7363 	    emsg(_("E975: Using a Blob as a Float"));
7364 	    break;
7365 	case VAR_UNKNOWN:
7366 	    internal_error("tv_get_float(UNKNOWN)");
7367 	    break;
7368     }
7369     return 0;
7370 }
7371 #endif
7372 
7373 /*
7374  * Get the string value of a variable.
7375  * If it is a Number variable, the number is converted into a string.
7376  * tv_get_string() uses a single, static buffer.  YOU CAN ONLY USE IT ONCE!
7377  * tv_get_string_buf() uses a given buffer.
7378  * If the String variable has never been set, return an empty string.
7379  * Never returns NULL;
7380  * tv_get_string_chk() and tv_get_string_buf_chk() are similar, but return
7381  * NULL on error.
7382  */
7383     char_u *
7384 tv_get_string(typval_T *varp)
7385 {
7386     static char_u   mybuf[NUMBUFLEN];
7387 
7388     return tv_get_string_buf(varp, mybuf);
7389 }
7390 
7391     char_u *
7392 tv_get_string_buf(typval_T *varp, char_u *buf)
7393 {
7394     char_u	*res =  tv_get_string_buf_chk(varp, buf);
7395 
7396     return res != NULL ? res : (char_u *)"";
7397 }
7398 
7399 /*
7400  * Careful: This uses a single, static buffer.  YOU CAN ONLY USE IT ONCE!
7401  */
7402     char_u *
7403 tv_get_string_chk(typval_T *varp)
7404 {
7405     static char_u   mybuf[NUMBUFLEN];
7406 
7407     return tv_get_string_buf_chk(varp, mybuf);
7408 }
7409 
7410     char_u *
7411 tv_get_string_buf_chk(typval_T *varp, char_u *buf)
7412 {
7413     switch (varp->v_type)
7414     {
7415 	case VAR_NUMBER:
7416 	    vim_snprintf((char *)buf, NUMBUFLEN, "%lld",
7417 					    (long_long_T)varp->vval.v_number);
7418 	    return buf;
7419 	case VAR_FUNC:
7420 	case VAR_PARTIAL:
7421 	    emsg(_("E729: using Funcref as a String"));
7422 	    break;
7423 	case VAR_LIST:
7424 	    emsg(_("E730: using List as a String"));
7425 	    break;
7426 	case VAR_DICT:
7427 	    emsg(_("E731: using Dictionary as a String"));
7428 	    break;
7429 	case VAR_FLOAT:
7430 #ifdef FEAT_FLOAT
7431 	    emsg(_(e_float_as_string));
7432 	    break;
7433 #endif
7434 	case VAR_STRING:
7435 	    if (varp->vval.v_string != NULL)
7436 		return varp->vval.v_string;
7437 	    return (char_u *)"";
7438 	case VAR_SPECIAL:
7439 	    STRCPY(buf, get_var_special_name(varp->vval.v_number));
7440 	    return buf;
7441         case VAR_BLOB:
7442 	    emsg(_("E976: using Blob as a String"));
7443 	    break;
7444 	case VAR_JOB:
7445 #ifdef FEAT_JOB_CHANNEL
7446 	    {
7447 		job_T *job = varp->vval.v_job;
7448 		char  *status;
7449 
7450 		if (job == NULL)
7451 		    return (char_u *)"no process";
7452 		status = job->jv_status == JOB_FAILED ? "fail"
7453 				: job->jv_status >= JOB_ENDED ? "dead"
7454 				: "run";
7455 # ifdef UNIX
7456 		vim_snprintf((char *)buf, NUMBUFLEN,
7457 			    "process %ld %s", (long)job->jv_pid, status);
7458 # elif defined(WIN32)
7459 		vim_snprintf((char *)buf, NUMBUFLEN,
7460 			    "process %ld %s",
7461 			    (long)job->jv_proc_info.dwProcessId,
7462 			    status);
7463 # else
7464 		/* fall-back */
7465 		vim_snprintf((char *)buf, NUMBUFLEN, "process ? %s", status);
7466 # endif
7467 		return buf;
7468 	    }
7469 #endif
7470 	    break;
7471 	case VAR_CHANNEL:
7472 #ifdef FEAT_JOB_CHANNEL
7473 	    {
7474 		channel_T *channel = varp->vval.v_channel;
7475 		char      *status = channel_status(channel, -1);
7476 
7477 		if (channel == NULL)
7478 		    vim_snprintf((char *)buf, NUMBUFLEN, "channel %s", status);
7479 		else
7480 		    vim_snprintf((char *)buf, NUMBUFLEN,
7481 				     "channel %d %s", channel->ch_id, status);
7482 		return buf;
7483 	    }
7484 #endif
7485 	    break;
7486 	case VAR_UNKNOWN:
7487 	    emsg(_("E908: using an invalid value as a String"));
7488 	    break;
7489     }
7490     return NULL;
7491 }
7492 
7493 /*
7494  * Turn a typeval into a string.  Similar to tv_get_string_buf() but uses
7495  * string() on Dict, List, etc.
7496  */
7497     char_u *
7498 tv_stringify(typval_T *varp, char_u *buf)
7499 {
7500     if (varp->v_type == VAR_LIST
7501 	    || varp->v_type == VAR_DICT
7502 	    || varp->v_type == VAR_FUNC
7503 	    || varp->v_type == VAR_PARTIAL
7504 	    || varp->v_type == VAR_FLOAT)
7505     {
7506 	typval_T tmp;
7507 
7508 	f_string(varp, &tmp);
7509 	tv_get_string_buf(&tmp, buf);
7510 	clear_tv(varp);
7511 	*varp = tmp;
7512 	return tmp.vval.v_string;
7513     }
7514     return tv_get_string_buf(varp, buf);
7515 }
7516 
7517 /*
7518  * Find variable "name" in the list of variables.
7519  * Return a pointer to it if found, NULL if not found.
7520  * Careful: "a:0" variables don't have a name.
7521  * When "htp" is not NULL we are writing to the variable, set "htp" to the
7522  * hashtab_T used.
7523  */
7524     dictitem_T *
7525 find_var(char_u *name, hashtab_T **htp, int no_autoload)
7526 {
7527     char_u	*varname;
7528     hashtab_T	*ht;
7529     dictitem_T	*ret = NULL;
7530 
7531     ht = find_var_ht(name, &varname);
7532     if (htp != NULL)
7533 	*htp = ht;
7534     if (ht == NULL)
7535 	return NULL;
7536     ret = find_var_in_ht(ht, *name, varname, no_autoload || htp != NULL);
7537     if (ret != NULL)
7538 	return ret;
7539 
7540     /* Search in parent scope for lambda */
7541     return find_var_in_scoped_ht(name, no_autoload || htp != NULL);
7542 }
7543 
7544 /*
7545  * Find variable "varname" in hashtab "ht" with name "htname".
7546  * Returns NULL if not found.
7547  */
7548     dictitem_T *
7549 find_var_in_ht(
7550     hashtab_T	*ht,
7551     int		htname,
7552     char_u	*varname,
7553     int		no_autoload)
7554 {
7555     hashitem_T	*hi;
7556 
7557     if (*varname == NUL)
7558     {
7559 	/* Must be something like "s:", otherwise "ht" would be NULL. */
7560 	switch (htname)
7561 	{
7562 	    case 's': return &SCRIPT_SV(current_sctx.sc_sid)->sv_var;
7563 	    case 'g': return &globvars_var;
7564 	    case 'v': return &vimvars_var;
7565 	    case 'b': return &curbuf->b_bufvar;
7566 	    case 'w': return &curwin->w_winvar;
7567 	    case 't': return &curtab->tp_winvar;
7568 	    case 'l': return get_funccal_local_var();
7569 	    case 'a': return get_funccal_args_var();
7570 	}
7571 	return NULL;
7572     }
7573 
7574     hi = hash_find(ht, varname);
7575     if (HASHITEM_EMPTY(hi))
7576     {
7577 	/* For global variables we may try auto-loading the script.  If it
7578 	 * worked find the variable again.  Don't auto-load a script if it was
7579 	 * loaded already, otherwise it would be loaded every time when
7580 	 * checking if a function name is a Funcref variable. */
7581 	if (ht == &globvarht && !no_autoload)
7582 	{
7583 	    /* Note: script_autoload() may make "hi" invalid. It must either
7584 	     * be obtained again or not used. */
7585 	    if (!script_autoload(varname, FALSE) || aborting())
7586 		return NULL;
7587 	    hi = hash_find(ht, varname);
7588 	}
7589 	if (HASHITEM_EMPTY(hi))
7590 	    return NULL;
7591     }
7592     return HI2DI(hi);
7593 }
7594 
7595 /*
7596  * Find the hashtab used for a variable name.
7597  * Return NULL if the name is not valid.
7598  * Set "varname" to the start of name without ':'.
7599  */
7600     hashtab_T *
7601 find_var_ht(char_u *name, char_u **varname)
7602 {
7603     hashitem_T	*hi;
7604     hashtab_T	*ht;
7605 
7606     if (name[0] == NUL)
7607 	return NULL;
7608     if (name[1] != ':')
7609     {
7610 	/* The name must not start with a colon or #. */
7611 	if (name[0] == ':' || name[0] == AUTOLOAD_CHAR)
7612 	    return NULL;
7613 	*varname = name;
7614 
7615 	/* "version" is "v:version" in all scopes */
7616 	hi = hash_find(&compat_hashtab, name);
7617 	if (!HASHITEM_EMPTY(hi))
7618 	    return &compat_hashtab;
7619 
7620 	ht = get_funccal_local_ht();
7621 	if (ht == NULL)
7622 	    return &globvarht;			/* global variable */
7623 	return ht;				/* local variable */
7624     }
7625     *varname = name + 2;
7626     if (*name == 'g')				/* global variable */
7627 	return &globvarht;
7628     /* There must be no ':' or '#' in the rest of the name, unless g: is used
7629      */
7630     if (vim_strchr(name + 2, ':') != NULL
7631 			       || vim_strchr(name + 2, AUTOLOAD_CHAR) != NULL)
7632 	return NULL;
7633     if (*name == 'b')				/* buffer variable */
7634 	return &curbuf->b_vars->dv_hashtab;
7635     if (*name == 'w')				/* window variable */
7636 	return &curwin->w_vars->dv_hashtab;
7637     if (*name == 't')				/* tab page variable */
7638 	return &curtab->tp_vars->dv_hashtab;
7639     if (*name == 'v')				/* v: variable */
7640 	return &vimvarht;
7641     if (*name == 'a')				/* a: function argument */
7642 	return get_funccal_args_ht();
7643     if (*name == 'l')				/* l: local function variable */
7644 	return get_funccal_local_ht();
7645     if (*name == 's'				/* script variable */
7646 	    && current_sctx.sc_sid > 0 && current_sctx.sc_sid <= ga_scripts.ga_len)
7647 	return &SCRIPT_VARS(current_sctx.sc_sid);
7648     return NULL;
7649 }
7650 
7651 /*
7652  * Get the string value of a (global/local) variable.
7653  * Note: see tv_get_string() for how long the pointer remains valid.
7654  * Returns NULL when it doesn't exist.
7655  */
7656     char_u *
7657 get_var_value(char_u *name)
7658 {
7659     dictitem_T	*v;
7660 
7661     v = find_var(name, NULL, FALSE);
7662     if (v == NULL)
7663 	return NULL;
7664     return tv_get_string(&v->di_tv);
7665 }
7666 
7667 /*
7668  * Allocate a new hashtab for a sourced script.  It will be used while
7669  * sourcing this script and when executing functions defined in the script.
7670  */
7671     void
7672 new_script_vars(scid_T id)
7673 {
7674     int		i;
7675     hashtab_T	*ht;
7676     scriptvar_T *sv;
7677 
7678     if (ga_grow(&ga_scripts, (int)(id - ga_scripts.ga_len)) == OK)
7679     {
7680 	/* Re-allocating ga_data means that an ht_array pointing to
7681 	 * ht_smallarray becomes invalid.  We can recognize this: ht_mask is
7682 	 * at its init value.  Also reset "v_dict", it's always the same. */
7683 	for (i = 1; i <= ga_scripts.ga_len; ++i)
7684 	{
7685 	    ht = &SCRIPT_VARS(i);
7686 	    if (ht->ht_mask == HT_INIT_SIZE - 1)
7687 		ht->ht_array = ht->ht_smallarray;
7688 	    sv = SCRIPT_SV(i);
7689 	    sv->sv_var.di_tv.vval.v_dict = &sv->sv_dict;
7690 	}
7691 
7692 	while (ga_scripts.ga_len < id)
7693 	{
7694 	    sv = SCRIPT_SV(ga_scripts.ga_len + 1) =
7695 		(scriptvar_T *)alloc_clear(sizeof(scriptvar_T));
7696 	    init_var_dict(&sv->sv_dict, &sv->sv_var, VAR_SCOPE);
7697 	    ++ga_scripts.ga_len;
7698 	}
7699     }
7700 }
7701 
7702 /*
7703  * Initialize dictionary "dict" as a scope and set variable "dict_var" to
7704  * point to it.
7705  */
7706     void
7707 init_var_dict(dict_T *dict, dictitem_T *dict_var, int scope)
7708 {
7709     hash_init(&dict->dv_hashtab);
7710     dict->dv_lock = 0;
7711     dict->dv_scope = scope;
7712     dict->dv_refcount = DO_NOT_FREE_CNT;
7713     dict->dv_copyID = 0;
7714     dict_var->di_tv.vval.v_dict = dict;
7715     dict_var->di_tv.v_type = VAR_DICT;
7716     dict_var->di_tv.v_lock = VAR_FIXED;
7717     dict_var->di_flags = DI_FLAGS_RO | DI_FLAGS_FIX;
7718     dict_var->di_key[0] = NUL;
7719 }
7720 
7721 /*
7722  * Unreference a dictionary initialized by init_var_dict().
7723  */
7724     void
7725 unref_var_dict(dict_T *dict)
7726 {
7727     /* Now the dict needs to be freed if no one else is using it, go back to
7728      * normal reference counting. */
7729     dict->dv_refcount -= DO_NOT_FREE_CNT - 1;
7730     dict_unref(dict);
7731 }
7732 
7733 /*
7734  * Clean up a list of internal variables.
7735  * Frees all allocated variables and the value they contain.
7736  * Clears hashtab "ht", does not free it.
7737  */
7738     void
7739 vars_clear(hashtab_T *ht)
7740 {
7741     vars_clear_ext(ht, TRUE);
7742 }
7743 
7744 /*
7745  * Like vars_clear(), but only free the value if "free_val" is TRUE.
7746  */
7747     void
7748 vars_clear_ext(hashtab_T *ht, int free_val)
7749 {
7750     int		todo;
7751     hashitem_T	*hi;
7752     dictitem_T	*v;
7753 
7754     hash_lock(ht);
7755     todo = (int)ht->ht_used;
7756     for (hi = ht->ht_array; todo > 0; ++hi)
7757     {
7758 	if (!HASHITEM_EMPTY(hi))
7759 	{
7760 	    --todo;
7761 
7762 	    /* Free the variable.  Don't remove it from the hashtab,
7763 	     * ht_array might change then.  hash_clear() takes care of it
7764 	     * later. */
7765 	    v = HI2DI(hi);
7766 	    if (free_val)
7767 		clear_tv(&v->di_tv);
7768 	    if (v->di_flags & DI_FLAGS_ALLOC)
7769 		vim_free(v);
7770 	}
7771     }
7772     hash_clear(ht);
7773     ht->ht_used = 0;
7774 }
7775 
7776 /*
7777  * Delete a variable from hashtab "ht" at item "hi".
7778  * Clear the variable value and free the dictitem.
7779  */
7780     static void
7781 delete_var(hashtab_T *ht, hashitem_T *hi)
7782 {
7783     dictitem_T	*di = HI2DI(hi);
7784 
7785     hash_remove(ht, hi);
7786     clear_tv(&di->di_tv);
7787     vim_free(di);
7788 }
7789 
7790 /*
7791  * List the value of one internal variable.
7792  */
7793     static void
7794 list_one_var(dictitem_T *v, char_u *prefix, int *first)
7795 {
7796     char_u	*tofree;
7797     char_u	*s;
7798     char_u	numbuf[NUMBUFLEN];
7799 
7800     s = echo_string(&v->di_tv, &tofree, numbuf, get_copyID());
7801     list_one_var_a(prefix, v->di_key, v->di_tv.v_type,
7802 					 s == NULL ? (char_u *)"" : s, first);
7803     vim_free(tofree);
7804 }
7805 
7806     static void
7807 list_one_var_a(
7808     char_u	*prefix,
7809     char_u	*name,
7810     int		type,
7811     char_u	*string,
7812     int		*first)  /* when TRUE clear rest of screen and set to FALSE */
7813 {
7814     /* don't use msg() or msg_attr() to avoid overwriting "v:statusmsg" */
7815     msg_start();
7816     msg_puts(prefix);
7817     if (name != NULL)	/* "a:" vars don't have a name stored */
7818 	msg_puts(name);
7819     msg_putchar(' ');
7820     msg_advance(22);
7821     if (type == VAR_NUMBER)
7822 	msg_putchar('#');
7823     else if (type == VAR_FUNC || type == VAR_PARTIAL)
7824 	msg_putchar('*');
7825     else if (type == VAR_LIST)
7826     {
7827 	msg_putchar('[');
7828 	if (*string == '[')
7829 	    ++string;
7830     }
7831     else if (type == VAR_DICT)
7832     {
7833 	msg_putchar('{');
7834 	if (*string == '{')
7835 	    ++string;
7836     }
7837     else
7838 	msg_putchar(' ');
7839 
7840     msg_outtrans(string);
7841 
7842     if (type == VAR_FUNC || type == VAR_PARTIAL)
7843 	msg_puts((char_u *)"()");
7844     if (*first)
7845     {
7846 	msg_clr_eos();
7847 	*first = FALSE;
7848     }
7849 }
7850 
7851 /*
7852  * Set variable "name" to value in "tv".
7853  * If the variable already exists, the value is updated.
7854  * Otherwise the variable is created.
7855  */
7856     void
7857 set_var(
7858     char_u	*name,
7859     typval_T	*tv,
7860     int		copy)	    /* make copy of value in "tv" */
7861 {
7862     dictitem_T	*v;
7863     char_u	*varname;
7864     hashtab_T	*ht;
7865 
7866     ht = find_var_ht(name, &varname);
7867     if (ht == NULL || *varname == NUL)
7868     {
7869 	semsg(_(e_illvar), name);
7870 	return;
7871     }
7872     v = find_var_in_ht(ht, 0, varname, TRUE);
7873 
7874     /* Search in parent scope which is possible to reference from lambda */
7875     if (v == NULL)
7876 	v = find_var_in_scoped_ht(name, TRUE);
7877 
7878     if ((tv->v_type == VAR_FUNC || tv->v_type == VAR_PARTIAL)
7879 				      && var_check_func_name(name, v == NULL))
7880 	return;
7881 
7882     if (v != NULL)
7883     {
7884 	/* existing variable, need to clear the value */
7885 	if (var_check_ro(v->di_flags, name, FALSE)
7886 			       || tv_check_lock(v->di_tv.v_lock, name, FALSE))
7887 	    return;
7888 
7889 	/*
7890 	 * Handle setting internal v: variables separately where needed to
7891 	 * prevent changing the type.
7892 	 */
7893 	if (ht == &vimvarht)
7894 	{
7895 	    if (v->di_tv.v_type == VAR_STRING)
7896 	    {
7897 		vim_free(v->di_tv.vval.v_string);
7898 		if (copy || tv->v_type != VAR_STRING)
7899 		    v->di_tv.vval.v_string = vim_strsave(tv_get_string(tv));
7900 		else
7901 		{
7902 		    /* Take over the string to avoid an extra alloc/free. */
7903 		    v->di_tv.vval.v_string = tv->vval.v_string;
7904 		    tv->vval.v_string = NULL;
7905 		}
7906 		return;
7907 	    }
7908 	    else if (v->di_tv.v_type == VAR_NUMBER)
7909 	    {
7910 		v->di_tv.vval.v_number = tv_get_number(tv);
7911 		if (STRCMP(varname, "searchforward") == 0)
7912 		    set_search_direction(v->di_tv.vval.v_number ? '/' : '?');
7913 #ifdef FEAT_SEARCH_EXTRA
7914 		else if (STRCMP(varname, "hlsearch") == 0)
7915 		{
7916 		    no_hlsearch = !v->di_tv.vval.v_number;
7917 		    redraw_all_later(SOME_VALID);
7918 		}
7919 #endif
7920 		return;
7921 	    }
7922 	    else if (v->di_tv.v_type != tv->v_type)
7923 	    {
7924 		semsg(_("E963: setting %s to value with wrong type"), name);
7925 		return;
7926 	    }
7927 	}
7928 
7929 	clear_tv(&v->di_tv);
7930     }
7931     else		    /* add a new variable */
7932     {
7933 	/* Can't add "v:" variable. */
7934 	if (ht == &vimvarht)
7935 	{
7936 	    semsg(_(e_illvar), name);
7937 	    return;
7938 	}
7939 
7940 	/* Make sure the variable name is valid. */
7941 	if (!valid_varname(varname))
7942 	    return;
7943 
7944 	v = (dictitem_T *)alloc((unsigned)(sizeof(dictitem_T)
7945 							  + STRLEN(varname)));
7946 	if (v == NULL)
7947 	    return;
7948 	STRCPY(v->di_key, varname);
7949 	if (hash_add(ht, DI2HIKEY(v)) == FAIL)
7950 	{
7951 	    vim_free(v);
7952 	    return;
7953 	}
7954 	v->di_flags = DI_FLAGS_ALLOC;
7955     }
7956 
7957     if (copy || tv->v_type == VAR_NUMBER || tv->v_type == VAR_FLOAT)
7958 	copy_tv(tv, &v->di_tv);
7959     else
7960     {
7961 	v->di_tv = *tv;
7962 	v->di_tv.v_lock = 0;
7963 	init_tv(tv);
7964     }
7965 }
7966 
7967 /*
7968  * Return TRUE if di_flags "flags" indicates variable "name" is read-only.
7969  * Also give an error message.
7970  */
7971     int
7972 var_check_ro(int flags, char_u *name, int use_gettext)
7973 {
7974     if (flags & DI_FLAGS_RO)
7975     {
7976 	semsg(_(e_readonlyvar), use_gettext ? (char_u *)_(name) : name);
7977 	return TRUE;
7978     }
7979     if ((flags & DI_FLAGS_RO_SBX) && sandbox)
7980     {
7981 	semsg(_(e_readonlysbx), use_gettext ? (char_u *)_(name) : name);
7982 	return TRUE;
7983     }
7984     return FALSE;
7985 }
7986 
7987 /*
7988  * Return TRUE if di_flags "flags" indicates variable "name" is fixed.
7989  * Also give an error message.
7990  */
7991     int
7992 var_check_fixed(int flags, char_u *name, int use_gettext)
7993 {
7994     if (flags & DI_FLAGS_FIX)
7995     {
7996 	semsg(_("E795: Cannot delete variable %s"),
7997 				      use_gettext ? (char_u *)_(name) : name);
7998 	return TRUE;
7999     }
8000     return FALSE;
8001 }
8002 
8003 /*
8004  * Check if a funcref is assigned to a valid variable name.
8005  * Return TRUE and give an error if not.
8006  */
8007     int
8008 var_check_func_name(
8009     char_u *name,    /* points to start of variable name */
8010     int    new_var)  /* TRUE when creating the variable */
8011 {
8012     /* Allow for w: b: s: and t:. */
8013     if (!(vim_strchr((char_u *)"wbst", name[0]) != NULL && name[1] == ':')
8014 	    && !ASCII_ISUPPER((name[0] != NUL && name[1] == ':')
8015 						     ? name[2] : name[0]))
8016     {
8017 	semsg(_("E704: Funcref variable name must start with a capital: %s"),
8018 									name);
8019 	return TRUE;
8020     }
8021     /* Don't allow hiding a function.  When "v" is not NULL we might be
8022      * assigning another function to the same var, the type is checked
8023      * below. */
8024     if (new_var && function_exists(name, FALSE))
8025     {
8026 	semsg(_("E705: Variable name conflicts with existing function: %s"),
8027 								    name);
8028 	return TRUE;
8029     }
8030     return FALSE;
8031 }
8032 
8033 /*
8034  * Check if a variable name is valid.
8035  * Return FALSE and give an error if not.
8036  */
8037     int
8038 valid_varname(char_u *varname)
8039 {
8040     char_u *p;
8041 
8042     for (p = varname; *p != NUL; ++p)
8043 	if (!eval_isnamec1(*p) && (p == varname || !VIM_ISDIGIT(*p))
8044 						   && *p != AUTOLOAD_CHAR)
8045 	{
8046 	    semsg(_(e_illvar), varname);
8047 	    return FALSE;
8048 	}
8049     return TRUE;
8050 }
8051 
8052 /*
8053  * Return TRUE if typeval "tv" is set to be locked (immutable).
8054  * Also give an error message, using "name" or _("name") when use_gettext is
8055  * TRUE.
8056  */
8057     int
8058 tv_check_lock(int lock, char_u *name, int use_gettext)
8059 {
8060     if (lock & VAR_LOCKED)
8061     {
8062 	semsg(_("E741: Value is locked: %s"),
8063 				name == NULL ? (char_u *)_("Unknown")
8064 					     : use_gettext ? (char_u *)_(name)
8065 					     : name);
8066 	return TRUE;
8067     }
8068     if (lock & VAR_FIXED)
8069     {
8070 	semsg(_("E742: Cannot change value of %s"),
8071 				name == NULL ? (char_u *)_("Unknown")
8072 					     : use_gettext ? (char_u *)_(name)
8073 					     : name);
8074 	return TRUE;
8075     }
8076     return FALSE;
8077 }
8078 
8079 /*
8080  * Copy the values from typval_T "from" to typval_T "to".
8081  * When needed allocates string or increases reference count.
8082  * Does not make a copy of a list or dict but copies the reference!
8083  * It is OK for "from" and "to" to point to the same item.  This is used to
8084  * make a copy later.
8085  */
8086     void
8087 copy_tv(typval_T *from, typval_T *to)
8088 {
8089     to->v_type = from->v_type;
8090     to->v_lock = 0;
8091     switch (from->v_type)
8092     {
8093 	case VAR_NUMBER:
8094 	case VAR_SPECIAL:
8095 	    to->vval.v_number = from->vval.v_number;
8096 	    break;
8097 	case VAR_FLOAT:
8098 #ifdef FEAT_FLOAT
8099 	    to->vval.v_float = from->vval.v_float;
8100 	    break;
8101 #endif
8102 	case VAR_JOB:
8103 #ifdef FEAT_JOB_CHANNEL
8104 	    to->vval.v_job = from->vval.v_job;
8105 	    if (to->vval.v_job != NULL)
8106 		++to->vval.v_job->jv_refcount;
8107 	    break;
8108 #endif
8109 	case VAR_CHANNEL:
8110 #ifdef FEAT_JOB_CHANNEL
8111 	    to->vval.v_channel = from->vval.v_channel;
8112 	    if (to->vval.v_channel != NULL)
8113 		++to->vval.v_channel->ch_refcount;
8114 	    break;
8115 #endif
8116 	case VAR_STRING:
8117 	case VAR_FUNC:
8118 	    if (from->vval.v_string == NULL)
8119 		to->vval.v_string = NULL;
8120 	    else
8121 	    {
8122 		to->vval.v_string = vim_strsave(from->vval.v_string);
8123 		if (from->v_type == VAR_FUNC)
8124 		    func_ref(to->vval.v_string);
8125 	    }
8126 	    break;
8127 	case VAR_PARTIAL:
8128 	    if (from->vval.v_partial == NULL)
8129 		to->vval.v_partial = NULL;
8130 	    else
8131 	    {
8132 		to->vval.v_partial = from->vval.v_partial;
8133 		++to->vval.v_partial->pt_refcount;
8134 	    }
8135 	    break;
8136 	case VAR_BLOB:
8137 	    if (from->vval.v_blob == NULL)
8138 		to->vval.v_blob = NULL;
8139 	    else
8140 	    {
8141 		to->vval.v_blob = from->vval.v_blob;
8142 		++to->vval.v_blob->bv_refcount;
8143 	    }
8144 	    break;
8145 	case VAR_LIST:
8146 	    if (from->vval.v_list == NULL)
8147 		to->vval.v_list = NULL;
8148 	    else
8149 	    {
8150 		to->vval.v_list = from->vval.v_list;
8151 		++to->vval.v_list->lv_refcount;
8152 	    }
8153 	    break;
8154 	case VAR_DICT:
8155 	    if (from->vval.v_dict == NULL)
8156 		to->vval.v_dict = NULL;
8157 	    else
8158 	    {
8159 		to->vval.v_dict = from->vval.v_dict;
8160 		++to->vval.v_dict->dv_refcount;
8161 	    }
8162 	    break;
8163 	case VAR_UNKNOWN:
8164 	    internal_error("copy_tv(UNKNOWN)");
8165 	    break;
8166     }
8167 }
8168 
8169 /*
8170  * Make a copy of an item.
8171  * Lists and Dictionaries are also copied.  A deep copy if "deep" is set.
8172  * For deepcopy() "copyID" is zero for a full copy or the ID for when a
8173  * reference to an already copied list/dict can be used.
8174  * Returns FAIL or OK.
8175  */
8176     int
8177 item_copy(
8178     typval_T	*from,
8179     typval_T	*to,
8180     int		deep,
8181     int		copyID)
8182 {
8183     static int	recurse = 0;
8184     int		ret = OK;
8185 
8186     if (recurse >= DICT_MAXNEST)
8187     {
8188 	emsg(_("E698: variable nested too deep for making a copy"));
8189 	return FAIL;
8190     }
8191     ++recurse;
8192 
8193     switch (from->v_type)
8194     {
8195 	case VAR_NUMBER:
8196 	case VAR_FLOAT:
8197 	case VAR_STRING:
8198 	case VAR_FUNC:
8199 	case VAR_PARTIAL:
8200 	case VAR_SPECIAL:
8201 	case VAR_JOB:
8202 	case VAR_CHANNEL:
8203 	    copy_tv(from, to);
8204 	    break;
8205 	case VAR_LIST:
8206 	    to->v_type = VAR_LIST;
8207 	    to->v_lock = 0;
8208 	    if (from->vval.v_list == NULL)
8209 		to->vval.v_list = NULL;
8210 	    else if (copyID != 0 && from->vval.v_list->lv_copyID == copyID)
8211 	    {
8212 		/* use the copy made earlier */
8213 		to->vval.v_list = from->vval.v_list->lv_copylist;
8214 		++to->vval.v_list->lv_refcount;
8215 	    }
8216 	    else
8217 		to->vval.v_list = list_copy(from->vval.v_list, deep, copyID);
8218 	    if (to->vval.v_list == NULL)
8219 		ret = FAIL;
8220 	    break;
8221 	case VAR_BLOB:
8222 	    to->v_type = VAR_BLOB;
8223 	    if (from->vval.v_blob == NULL)
8224 		to->vval.v_blob = NULL;
8225 	    else if (rettv_blob_alloc(to) == FAIL)
8226 		ret = FAIL;
8227 	    else
8228 	    {
8229 		int  len = from->vval.v_blob->bv_ga.ga_len;
8230 
8231 		to->vval.v_blob->bv_ga.ga_data =
8232 			    vim_memsave(from->vval.v_blob->bv_ga.ga_data, len);
8233 		to->vval.v_blob->bv_ga.ga_len = len;
8234 	    }
8235 	    break;
8236 	case VAR_DICT:
8237 	    to->v_type = VAR_DICT;
8238 	    to->v_lock = 0;
8239 	    if (from->vval.v_dict == NULL)
8240 		to->vval.v_dict = NULL;
8241 	    else if (copyID != 0 && from->vval.v_dict->dv_copyID == copyID)
8242 	    {
8243 		/* use the copy made earlier */
8244 		to->vval.v_dict = from->vval.v_dict->dv_copydict;
8245 		++to->vval.v_dict->dv_refcount;
8246 	    }
8247 	    else
8248 		to->vval.v_dict = dict_copy(from->vval.v_dict, deep, copyID);
8249 	    if (to->vval.v_dict == NULL)
8250 		ret = FAIL;
8251 	    break;
8252 	case VAR_UNKNOWN:
8253 	    internal_error("item_copy(UNKNOWN)");
8254 	    ret = FAIL;
8255     }
8256     --recurse;
8257     return ret;
8258 }
8259 
8260 /*
8261  * This function is used by f_input() and f_inputdialog() functions. The third
8262  * argument to f_input() specifies the type of completion to use at the
8263  * prompt. The third argument to f_inputdialog() specifies the value to return
8264  * when the user cancels the prompt.
8265  */
8266     void
8267 get_user_input(
8268     typval_T	*argvars,
8269     typval_T	*rettv,
8270     int		inputdialog,
8271     int		secret)
8272 {
8273     char_u	*prompt = tv_get_string_chk(&argvars[0]);
8274     char_u	*p = NULL;
8275     int		c;
8276     char_u	buf[NUMBUFLEN];
8277     int		cmd_silent_save = cmd_silent;
8278     char_u	*defstr = (char_u *)"";
8279     int		xp_type = EXPAND_NOTHING;
8280     char_u	*xp_arg = NULL;
8281 
8282     rettv->v_type = VAR_STRING;
8283     rettv->vval.v_string = NULL;
8284 
8285 #ifdef NO_CONSOLE_INPUT
8286     /* While starting up, there is no place to enter text. When running tests
8287      * with --not-a-term we assume feedkeys() will be used. */
8288     if (no_console_input() && !is_not_a_term())
8289 	return;
8290 #endif
8291 
8292     cmd_silent = FALSE;		/* Want to see the prompt. */
8293     if (prompt != NULL)
8294     {
8295 	/* Only the part of the message after the last NL is considered as
8296 	 * prompt for the command line */
8297 	p = vim_strrchr(prompt, '\n');
8298 	if (p == NULL)
8299 	    p = prompt;
8300 	else
8301 	{
8302 	    ++p;
8303 	    c = *p;
8304 	    *p = NUL;
8305 	    msg_start();
8306 	    msg_clr_eos();
8307 	    msg_puts_attr(prompt, echo_attr);
8308 	    msg_didout = FALSE;
8309 	    msg_starthere();
8310 	    *p = c;
8311 	}
8312 	cmdline_row = msg_row;
8313 
8314 	if (argvars[1].v_type != VAR_UNKNOWN)
8315 	{
8316 	    defstr = tv_get_string_buf_chk(&argvars[1], buf);
8317 	    if (defstr != NULL)
8318 		stuffReadbuffSpec(defstr);
8319 
8320 	    if (!inputdialog && argvars[2].v_type != VAR_UNKNOWN)
8321 	    {
8322 		char_u	*xp_name;
8323 		int	xp_namelen;
8324 		long	argt;
8325 
8326 		/* input() with a third argument: completion */
8327 		rettv->vval.v_string = NULL;
8328 
8329 		xp_name = tv_get_string_buf_chk(&argvars[2], buf);
8330 		if (xp_name == NULL)
8331 		    return;
8332 
8333 		xp_namelen = (int)STRLEN(xp_name);
8334 
8335 		if (parse_compl_arg(xp_name, xp_namelen, &xp_type, &argt,
8336 							     &xp_arg) == FAIL)
8337 		    return;
8338 	    }
8339 	}
8340 
8341 	if (defstr != NULL)
8342 	{
8343 	    int save_ex_normal_busy = ex_normal_busy;
8344 
8345 	    ex_normal_busy = 0;
8346 	    rettv->vval.v_string =
8347 		getcmdline_prompt(secret ? NUL : '@', p, echo_attr,
8348 							      xp_type, xp_arg);
8349 	    ex_normal_busy = save_ex_normal_busy;
8350 	}
8351 	if (inputdialog && rettv->vval.v_string == NULL
8352 		&& argvars[1].v_type != VAR_UNKNOWN
8353 		&& argvars[2].v_type != VAR_UNKNOWN)
8354 	    rettv->vval.v_string = vim_strsave(tv_get_string_buf(
8355 							   &argvars[2], buf));
8356 
8357 	vim_free(xp_arg);
8358 
8359 	/* since the user typed this, no need to wait for return */
8360 	need_wait_return = FALSE;
8361 	msg_didout = FALSE;
8362     }
8363     cmd_silent = cmd_silent_save;
8364 }
8365 
8366 /*
8367  * ":echo expr1 ..."	print each argument separated with a space, add a
8368  *			newline at the end.
8369  * ":echon expr1 ..."	print each argument plain.
8370  */
8371     void
8372 ex_echo(exarg_T *eap)
8373 {
8374     char_u	*arg = eap->arg;
8375     typval_T	rettv;
8376     char_u	*tofree;
8377     char_u	*p;
8378     int		needclr = TRUE;
8379     int		atstart = TRUE;
8380     char_u	numbuf[NUMBUFLEN];
8381     int		did_emsg_before = did_emsg;
8382     int		called_emsg_before = called_emsg;
8383 
8384     if (eap->skip)
8385 	++emsg_skip;
8386     while (*arg != NUL && *arg != '|' && *arg != '\n' && !got_int)
8387     {
8388 	/* If eval1() causes an error message the text from the command may
8389 	 * still need to be cleared. E.g., "echo 22,44". */
8390 	need_clr_eos = needclr;
8391 
8392 	p = arg;
8393 	if (eval1(&arg, &rettv, !eap->skip) == FAIL)
8394 	{
8395 	    /*
8396 	     * Report the invalid expression unless the expression evaluation
8397 	     * has been cancelled due to an aborting error, an interrupt, or an
8398 	     * exception.
8399 	     */
8400 	    if (!aborting() && did_emsg == did_emsg_before
8401 					  && called_emsg == called_emsg_before)
8402 		semsg(_(e_invexpr2), p);
8403 	    need_clr_eos = FALSE;
8404 	    break;
8405 	}
8406 	need_clr_eos = FALSE;
8407 
8408 	if (!eap->skip)
8409 	{
8410 	    if (atstart)
8411 	    {
8412 		atstart = FALSE;
8413 		/* Call msg_start() after eval1(), evaluating the expression
8414 		 * may cause a message to appear. */
8415 		if (eap->cmdidx == CMD_echo)
8416 		{
8417 		    /* Mark the saved text as finishing the line, so that what
8418 		     * follows is displayed on a new line when scrolling back
8419 		     * at the more prompt. */
8420 		    msg_sb_eol();
8421 		    msg_start();
8422 		}
8423 	    }
8424 	    else if (eap->cmdidx == CMD_echo)
8425 		msg_puts_attr((char_u *)" ", echo_attr);
8426 	    p = echo_string(&rettv, &tofree, numbuf, get_copyID());
8427 	    if (p != NULL)
8428 		for ( ; *p != NUL && !got_int; ++p)
8429 		{
8430 		    if (*p == '\n' || *p == '\r' || *p == TAB)
8431 		    {
8432 			if (*p != TAB && needclr)
8433 			{
8434 			    /* remove any text still there from the command */
8435 			    msg_clr_eos();
8436 			    needclr = FALSE;
8437 			}
8438 			msg_putchar_attr(*p, echo_attr);
8439 		    }
8440 		    else
8441 		    {
8442 #ifdef FEAT_MBYTE
8443 			if (has_mbyte)
8444 			{
8445 			    int i = (*mb_ptr2len)(p);
8446 
8447 			    (void)msg_outtrans_len_attr(p, i, echo_attr);
8448 			    p += i - 1;
8449 			}
8450 			else
8451 #endif
8452 			    (void)msg_outtrans_len_attr(p, 1, echo_attr);
8453 		    }
8454 		}
8455 	    vim_free(tofree);
8456 	}
8457 	clear_tv(&rettv);
8458 	arg = skipwhite(arg);
8459     }
8460     eap->nextcmd = check_nextcmd(arg);
8461 
8462     if (eap->skip)
8463 	--emsg_skip;
8464     else
8465     {
8466 	/* remove text that may still be there from the command */
8467 	if (needclr)
8468 	    msg_clr_eos();
8469 	if (eap->cmdidx == CMD_echo)
8470 	    msg_end();
8471     }
8472 }
8473 
8474 /*
8475  * ":echohl {name}".
8476  */
8477     void
8478 ex_echohl(exarg_T *eap)
8479 {
8480     echo_attr = syn_name2attr(eap->arg);
8481 }
8482 
8483 /*
8484  * ":execute expr1 ..."	execute the result of an expression.
8485  * ":echomsg expr1 ..."	Print a message
8486  * ":echoerr expr1 ..."	Print an error
8487  * Each gets spaces around each argument and a newline at the end for
8488  * echo commands
8489  */
8490     void
8491 ex_execute(exarg_T *eap)
8492 {
8493     char_u	*arg = eap->arg;
8494     typval_T	rettv;
8495     int		ret = OK;
8496     char_u	*p;
8497     garray_T	ga;
8498     int		len;
8499     int		save_did_emsg = did_emsg;
8500 
8501     ga_init2(&ga, 1, 80);
8502 
8503     if (eap->skip)
8504 	++emsg_skip;
8505     while (*arg != NUL && *arg != '|' && *arg != '\n')
8506     {
8507 	p = arg;
8508 	ret = eval1_emsg(&arg, &rettv, !eap->skip);
8509 	if (ret == FAIL)
8510 	    break;
8511 
8512 	if (!eap->skip)
8513 	{
8514 	    char_u   buf[NUMBUFLEN];
8515 
8516 	    if (eap->cmdidx == CMD_execute)
8517 		p = tv_get_string_buf(&rettv, buf);
8518 	    else
8519 		p = tv_stringify(&rettv, buf);
8520 	    len = (int)STRLEN(p);
8521 	    if (ga_grow(&ga, len + 2) == FAIL)
8522 	    {
8523 		clear_tv(&rettv);
8524 		ret = FAIL;
8525 		break;
8526 	    }
8527 	    if (ga.ga_len)
8528 		((char_u *)(ga.ga_data))[ga.ga_len++] = ' ';
8529 	    STRCPY((char_u *)(ga.ga_data) + ga.ga_len, p);
8530 	    ga.ga_len += len;
8531 	}
8532 
8533 	clear_tv(&rettv);
8534 	arg = skipwhite(arg);
8535     }
8536 
8537     if (ret != FAIL && ga.ga_data != NULL)
8538     {
8539 	if (eap->cmdidx == CMD_echomsg || eap->cmdidx == CMD_echoerr)
8540 	{
8541 	    /* Mark the already saved text as finishing the line, so that what
8542 	     * follows is displayed on a new line when scrolling back at the
8543 	     * more prompt. */
8544 	    msg_sb_eol();
8545 	}
8546 
8547 	if (eap->cmdidx == CMD_echomsg)
8548 	{
8549 	    MSG_ATTR(ga.ga_data, echo_attr);
8550 	    out_flush();
8551 	}
8552 	else if (eap->cmdidx == CMD_echoerr)
8553 	{
8554 	    /* We don't want to abort following commands, restore did_emsg. */
8555 	    save_did_emsg = did_emsg;
8556 	    emsg(ga.ga_data);
8557 	    if (!force_abort)
8558 		did_emsg = save_did_emsg;
8559 	}
8560 	else if (eap->cmdidx == CMD_execute)
8561 	    do_cmdline((char_u *)ga.ga_data,
8562 		       eap->getline, eap->cookie, DOCMD_NOWAIT|DOCMD_VERBOSE);
8563     }
8564 
8565     ga_clear(&ga);
8566 
8567     if (eap->skip)
8568 	--emsg_skip;
8569 
8570     eap->nextcmd = check_nextcmd(arg);
8571 }
8572 
8573 /*
8574  * Find window specified by "vp" in tabpage "tp".
8575  */
8576     win_T *
8577 find_win_by_nr(
8578     typval_T	*vp,
8579     tabpage_T	*tp)	/* NULL for current tab page */
8580 {
8581     win_T	*wp;
8582     int		nr = (int)tv_get_number_chk(vp, NULL);
8583 
8584     if (nr < 0)
8585 	return NULL;
8586     if (nr == 0)
8587 	return curwin;
8588 
8589     FOR_ALL_WINDOWS_IN_TAB(tp, wp)
8590     {
8591 	if (nr >= LOWEST_WIN_ID)
8592 	{
8593 	    if (wp->w_id == nr)
8594 		return wp;
8595 	}
8596 	else if (--nr <= 0)
8597 	    break;
8598     }
8599     if (nr >= LOWEST_WIN_ID)
8600 	return NULL;
8601     return wp;
8602 }
8603 
8604 /*
8605  * Find a window: When using a Window ID in any tab page, when using a number
8606  * in the current tab page.
8607  */
8608     win_T *
8609 find_win_by_nr_or_id(typval_T *vp)
8610 {
8611     int	nr = (int)tv_get_number_chk(vp, NULL);
8612 
8613     if (nr >= LOWEST_WIN_ID)
8614 	return win_id2wp(vp);
8615     return find_win_by_nr(vp, NULL);
8616 }
8617 
8618 /*
8619  * Find window specified by "wvp" in tabpage "tvp".
8620  */
8621     win_T *
8622 find_tabwin(
8623     typval_T	*wvp,	/* VAR_UNKNOWN for current window */
8624     typval_T	*tvp)	/* VAR_UNKNOWN for current tab page */
8625 {
8626     win_T	*wp = NULL;
8627     tabpage_T	*tp = NULL;
8628     long	n;
8629 
8630     if (wvp->v_type != VAR_UNKNOWN)
8631     {
8632 	if (tvp->v_type != VAR_UNKNOWN)
8633 	{
8634 	    n = (long)tv_get_number(tvp);
8635 	    if (n >= 0)
8636 		tp = find_tabpage(n);
8637 	}
8638 	else
8639 	    tp = curtab;
8640 
8641 	if (tp != NULL)
8642 	    wp = find_win_by_nr(wvp, tp);
8643     }
8644     else
8645 	wp = curwin;
8646 
8647     return wp;
8648 }
8649 
8650 /*
8651  * getwinvar() and gettabwinvar()
8652  */
8653     void
8654 getwinvar(
8655     typval_T	*argvars,
8656     typval_T	*rettv,
8657     int		off)	    /* 1 for gettabwinvar() */
8658 {
8659     win_T	*win;
8660     char_u	*varname;
8661     dictitem_T	*v;
8662     tabpage_T	*tp = NULL;
8663     int		done = FALSE;
8664     win_T	*oldcurwin;
8665     tabpage_T	*oldtabpage;
8666     int		need_switch_win;
8667 
8668     if (off == 1)
8669 	tp = find_tabpage((int)tv_get_number_chk(&argvars[0], NULL));
8670     else
8671 	tp = curtab;
8672     win = find_win_by_nr(&argvars[off], tp);
8673     varname = tv_get_string_chk(&argvars[off + 1]);
8674     ++emsg_off;
8675 
8676     rettv->v_type = VAR_STRING;
8677     rettv->vval.v_string = NULL;
8678 
8679     if (win != NULL && varname != NULL)
8680     {
8681 	/* Set curwin to be our win, temporarily.  Also set the tabpage,
8682 	 * otherwise the window is not valid. Only do this when needed,
8683 	 * autocommands get blocked. */
8684 	need_switch_win = !(tp == curtab && win == curwin);
8685 	if (!need_switch_win
8686 		  || switch_win(&oldcurwin, &oldtabpage, win, tp, TRUE) == OK)
8687 	{
8688 	    if (*varname == '&')
8689 	    {
8690 		if (varname[1] == NUL)
8691 		{
8692 		    /* get all window-local options in a dict */
8693 		    dict_T	*opts = get_winbuf_options(FALSE);
8694 
8695 		    if (opts != NULL)
8696 		    {
8697 			rettv_dict_set(rettv, opts);
8698 			done = TRUE;
8699 		    }
8700 		}
8701 		else if (get_option_tv(&varname, rettv, 1) == OK)
8702 		    /* window-local-option */
8703 		    done = TRUE;
8704 	    }
8705 	    else
8706 	    {
8707 		/* Look up the variable. */
8708 		/* Let getwinvar({nr}, "") return the "w:" dictionary. */
8709 		v = find_var_in_ht(&win->w_vars->dv_hashtab, 'w',
8710 							      varname, FALSE);
8711 		if (v != NULL)
8712 		{
8713 		    copy_tv(&v->di_tv, rettv);
8714 		    done = TRUE;
8715 		}
8716 	    }
8717 	}
8718 
8719 	if (need_switch_win)
8720 	    /* restore previous notion of curwin */
8721 	    restore_win(oldcurwin, oldtabpage, TRUE);
8722     }
8723 
8724     if (!done && argvars[off + 2].v_type != VAR_UNKNOWN)
8725 	/* use the default return value */
8726 	copy_tv(&argvars[off + 2], rettv);
8727 
8728     --emsg_off;
8729 }
8730 
8731 /*
8732  * "setwinvar()" and "settabwinvar()" functions
8733  */
8734     void
8735 setwinvar(typval_T *argvars, typval_T *rettv UNUSED, int off)
8736 {
8737     win_T	*win;
8738     win_T	*save_curwin;
8739     tabpage_T	*save_curtab;
8740     int		need_switch_win;
8741     char_u	*varname, *winvarname;
8742     typval_T	*varp;
8743     char_u	nbuf[NUMBUFLEN];
8744     tabpage_T	*tp = NULL;
8745 
8746     if (check_restricted() || check_secure())
8747 	return;
8748 
8749     if (off == 1)
8750 	tp = find_tabpage((int)tv_get_number_chk(&argvars[0], NULL));
8751     else
8752 	tp = curtab;
8753     win = find_win_by_nr(&argvars[off], tp);
8754     varname = tv_get_string_chk(&argvars[off + 1]);
8755     varp = &argvars[off + 2];
8756 
8757     if (win != NULL && varname != NULL && varp != NULL)
8758     {
8759 	need_switch_win = !(tp == curtab && win == curwin);
8760 	if (!need_switch_win
8761 	       || switch_win(&save_curwin, &save_curtab, win, tp, TRUE) == OK)
8762 	{
8763 	    if (*varname == '&')
8764 	    {
8765 		long	numval;
8766 		char_u	*strval;
8767 		int		error = FALSE;
8768 
8769 		++varname;
8770 		numval = (long)tv_get_number_chk(varp, &error);
8771 		strval = tv_get_string_buf_chk(varp, nbuf);
8772 		if (!error && strval != NULL)
8773 		    set_option_value(varname, numval, strval, OPT_LOCAL);
8774 	    }
8775 	    else
8776 	    {
8777 		winvarname = alloc((unsigned)STRLEN(varname) + 3);
8778 		if (winvarname != NULL)
8779 		{
8780 		    STRCPY(winvarname, "w:");
8781 		    STRCPY(winvarname + 2, varname);
8782 		    set_var(winvarname, varp, TRUE);
8783 		    vim_free(winvarname);
8784 		}
8785 	    }
8786 	}
8787 	if (need_switch_win)
8788 	    restore_win(save_curwin, save_curtab, TRUE);
8789     }
8790 }
8791 
8792 /*
8793  * Skip over the name of an option: "&option", "&g:option" or "&l:option".
8794  * "arg" points to the "&" or '+' when called, to "option" when returning.
8795  * Returns NULL when no option name found.  Otherwise pointer to the char
8796  * after the option name.
8797  */
8798     static char_u *
8799 find_option_end(char_u **arg, int *opt_flags)
8800 {
8801     char_u	*p = *arg;
8802 
8803     ++p;
8804     if (*p == 'g' && p[1] == ':')
8805     {
8806 	*opt_flags = OPT_GLOBAL;
8807 	p += 2;
8808     }
8809     else if (*p == 'l' && p[1] == ':')
8810     {
8811 	*opt_flags = OPT_LOCAL;
8812 	p += 2;
8813     }
8814     else
8815 	*opt_flags = 0;
8816 
8817     if (!ASCII_ISALPHA(*p))
8818 	return NULL;
8819     *arg = p;
8820 
8821     if (p[0] == 't' && p[1] == '_' && p[2] != NUL && p[3] != NUL)
8822 	p += 4;	    /* termcap option */
8823     else
8824 	while (ASCII_ISALPHA(*p))
8825 	    ++p;
8826     return p;
8827 }
8828 
8829 /*
8830  * Return the autoload script name for a function or variable name.
8831  * Returns NULL when out of memory.
8832  */
8833     char_u *
8834 autoload_name(char_u *name)
8835 {
8836     char_u	*p;
8837     char_u	*scriptname;
8838 
8839     /* Get the script file name: replace '#' with '/', append ".vim". */
8840     scriptname = alloc((unsigned)(STRLEN(name) + 14));
8841     if (scriptname == NULL)
8842 	return FALSE;
8843     STRCPY(scriptname, "autoload/");
8844     STRCAT(scriptname, name);
8845     *vim_strrchr(scriptname, AUTOLOAD_CHAR) = NUL;
8846     STRCAT(scriptname, ".vim");
8847     while ((p = vim_strchr(scriptname, AUTOLOAD_CHAR)) != NULL)
8848 	*p = '/';
8849     return scriptname;
8850 }
8851 
8852 /*
8853  * If "name" has a package name try autoloading the script for it.
8854  * Return TRUE if a package was loaded.
8855  */
8856     int
8857 script_autoload(
8858     char_u	*name,
8859     int		reload)	    /* load script again when already loaded */
8860 {
8861     char_u	*p;
8862     char_u	*scriptname, *tofree;
8863     int		ret = FALSE;
8864     int		i;
8865 
8866     /* If there is no '#' after name[0] there is no package name. */
8867     p = vim_strchr(name, AUTOLOAD_CHAR);
8868     if (p == NULL || p == name)
8869 	return FALSE;
8870 
8871     tofree = scriptname = autoload_name(name);
8872 
8873     /* Find the name in the list of previously loaded package names.  Skip
8874      * "autoload/", it's always the same. */
8875     for (i = 0; i < ga_loaded.ga_len; ++i)
8876 	if (STRCMP(((char_u **)ga_loaded.ga_data)[i] + 9, scriptname + 9) == 0)
8877 	    break;
8878     if (!reload && i < ga_loaded.ga_len)
8879 	ret = FALSE;	    /* was loaded already */
8880     else
8881     {
8882 	/* Remember the name if it wasn't loaded already. */
8883 	if (i == ga_loaded.ga_len && ga_grow(&ga_loaded, 1) == OK)
8884 	{
8885 	    ((char_u **)ga_loaded.ga_data)[ga_loaded.ga_len++] = scriptname;
8886 	    tofree = NULL;
8887 	}
8888 
8889 	/* Try loading the package from $VIMRUNTIME/autoload/<name>.vim */
8890 	if (source_runtime(scriptname, 0) == OK)
8891 	    ret = TRUE;
8892     }
8893 
8894     vim_free(tofree);
8895     return ret;
8896 }
8897 
8898 #if defined(FEAT_VIMINFO) || defined(FEAT_SESSION)
8899 typedef enum
8900 {
8901     VAR_FLAVOUR_DEFAULT,	/* doesn't start with uppercase */
8902     VAR_FLAVOUR_SESSION,	/* starts with uppercase, some lower */
8903     VAR_FLAVOUR_VIMINFO		/* all uppercase */
8904 } var_flavour_T;
8905 
8906     static var_flavour_T
8907 var_flavour(char_u *varname)
8908 {
8909     char_u *p = varname;
8910 
8911     if (ASCII_ISUPPER(*p))
8912     {
8913 	while (*(++p))
8914 	    if (ASCII_ISLOWER(*p))
8915 		return VAR_FLAVOUR_SESSION;
8916 	return VAR_FLAVOUR_VIMINFO;
8917     }
8918     else
8919 	return VAR_FLAVOUR_DEFAULT;
8920 }
8921 #endif
8922 
8923 #if defined(FEAT_VIMINFO) || defined(PROTO)
8924 /*
8925  * Restore global vars that start with a capital from the viminfo file
8926  */
8927     int
8928 read_viminfo_varlist(vir_T *virp, int writing)
8929 {
8930     char_u	*tab;
8931     int		type = VAR_NUMBER;
8932     typval_T	tv;
8933     funccal_entry_T funccal_entry;
8934 
8935     if (!writing && (find_viminfo_parameter('!') != NULL))
8936     {
8937 	tab = vim_strchr(virp->vir_line + 1, '\t');
8938 	if (tab != NULL)
8939 	{
8940 	    *tab++ = '\0';	/* isolate the variable name */
8941 	    switch (*tab)
8942 	    {
8943 		case 'S': type = VAR_STRING; break;
8944 #ifdef FEAT_FLOAT
8945 		case 'F': type = VAR_FLOAT; break;
8946 #endif
8947 		case 'D': type = VAR_DICT; break;
8948 		case 'L': type = VAR_LIST; break;
8949 		case 'B': type = VAR_BLOB; break;
8950 		case 'X': type = VAR_SPECIAL; break;
8951 	    }
8952 
8953 	    tab = vim_strchr(tab, '\t');
8954 	    if (tab != NULL)
8955 	    {
8956 		tv.v_type = type;
8957 		if (type == VAR_STRING || type == VAR_DICT
8958 			|| type == VAR_LIST || type == VAR_BLOB)
8959 		    tv.vval.v_string = viminfo_readstring(virp,
8960 				       (int)(tab - virp->vir_line + 1), TRUE);
8961 #ifdef FEAT_FLOAT
8962 		else if (type == VAR_FLOAT)
8963 		    (void)string2float(tab + 1, &tv.vval.v_float);
8964 #endif
8965 		else
8966 		    tv.vval.v_number = atol((char *)tab + 1);
8967 		if (type == VAR_DICT || type == VAR_LIST)
8968 		{
8969 		    typval_T *etv = eval_expr(tv.vval.v_string, NULL);
8970 
8971 		    if (etv == NULL)
8972 			/* Failed to parse back the dict or list, use it as a
8973 			 * string. */
8974 			tv.v_type = VAR_STRING;
8975 		    else
8976 		    {
8977 			vim_free(tv.vval.v_string);
8978 			tv = *etv;
8979 			vim_free(etv);
8980 		    }
8981 		}
8982 		else if (type == VAR_BLOB)
8983 		{
8984 		    blob_T *blob = string2blob(tv.vval.v_string);
8985 
8986 		    if (blob == NULL)
8987 			// Failed to parse back the blob, use it as a string.
8988 			tv.v_type = VAR_STRING;
8989 		    else
8990 		    {
8991 			vim_free(tv.vval.v_string);
8992 			tv.v_type = VAR_BLOB;
8993 			tv.vval.v_blob = blob;
8994 		    }
8995 		}
8996 
8997 		/* when in a function use global variables */
8998 		save_funccal(&funccal_entry);
8999 		set_var(virp->vir_line + 1, &tv, FALSE);
9000 		restore_funccal();
9001 
9002 		if (tv.v_type == VAR_STRING)
9003 		    vim_free(tv.vval.v_string);
9004 		else if (tv.v_type == VAR_DICT || tv.v_type == VAR_LIST ||
9005 			tv.v_type == VAR_BLOB)
9006 		    clear_tv(&tv);
9007 	    }
9008 	}
9009     }
9010 
9011     return viminfo_readline(virp);
9012 }
9013 
9014 /*
9015  * Write global vars that start with a capital to the viminfo file
9016  */
9017     void
9018 write_viminfo_varlist(FILE *fp)
9019 {
9020     hashitem_T	*hi;
9021     dictitem_T	*this_var;
9022     int		todo;
9023     char	*s = "";
9024     char_u	*p;
9025     char_u	*tofree;
9026     char_u	numbuf[NUMBUFLEN];
9027 
9028     if (find_viminfo_parameter('!') == NULL)
9029 	return;
9030 
9031     fputs(_("\n# global variables:\n"), fp);
9032 
9033     todo = (int)globvarht.ht_used;
9034     for (hi = globvarht.ht_array; todo > 0; ++hi)
9035     {
9036 	if (!HASHITEM_EMPTY(hi))
9037 	{
9038 	    --todo;
9039 	    this_var = HI2DI(hi);
9040 	    if (var_flavour(this_var->di_key) == VAR_FLAVOUR_VIMINFO)
9041 	    {
9042 		switch (this_var->di_tv.v_type)
9043 		{
9044 		    case VAR_STRING: s = "STR"; break;
9045 		    case VAR_NUMBER: s = "NUM"; break;
9046 		    case VAR_FLOAT:  s = "FLO"; break;
9047 		    case VAR_DICT:   s = "DIC"; break;
9048 		    case VAR_LIST:   s = "LIS"; break;
9049 		    case VAR_BLOB:   s = "BLO"; break;
9050 		    case VAR_SPECIAL: s = "XPL"; break;
9051 
9052 		    case VAR_UNKNOWN:
9053 		    case VAR_FUNC:
9054 		    case VAR_PARTIAL:
9055 		    case VAR_JOB:
9056 		    case VAR_CHANNEL:
9057 				     continue;
9058 		}
9059 		fprintf(fp, "!%s\t%s\t", this_var->di_key, s);
9060 		if (this_var->di_tv.v_type == VAR_SPECIAL)
9061 		{
9062 		    sprintf((char *)numbuf, "%ld",
9063 					  (long)this_var->di_tv.vval.v_number);
9064 		    p = numbuf;
9065 		    tofree = NULL;
9066 		}
9067 		else
9068 		    p = echo_string(&this_var->di_tv, &tofree, numbuf, 0);
9069 		if (p != NULL)
9070 		    viminfo_writestring(fp, p);
9071 		vim_free(tofree);
9072 	    }
9073 	}
9074     }
9075 }
9076 #endif
9077 
9078 #if defined(FEAT_SESSION) || defined(PROTO)
9079     int
9080 store_session_globals(FILE *fd)
9081 {
9082     hashitem_T	*hi;
9083     dictitem_T	*this_var;
9084     int		todo;
9085     char_u	*p, *t;
9086 
9087     todo = (int)globvarht.ht_used;
9088     for (hi = globvarht.ht_array; todo > 0; ++hi)
9089     {
9090 	if (!HASHITEM_EMPTY(hi))
9091 	{
9092 	    --todo;
9093 	    this_var = HI2DI(hi);
9094 	    if ((this_var->di_tv.v_type == VAR_NUMBER
9095 			|| this_var->di_tv.v_type == VAR_STRING)
9096 		    && var_flavour(this_var->di_key) == VAR_FLAVOUR_SESSION)
9097 	    {
9098 		/* Escape special characters with a backslash.  Turn a LF and
9099 		 * CR into \n and \r. */
9100 		p = vim_strsave_escaped(tv_get_string(&this_var->di_tv),
9101 							(char_u *)"\\\"\n\r");
9102 		if (p == NULL)	    /* out of memory */
9103 		    break;
9104 		for (t = p; *t != NUL; ++t)
9105 		    if (*t == '\n')
9106 			*t = 'n';
9107 		    else if (*t == '\r')
9108 			*t = 'r';
9109 		if ((fprintf(fd, "let %s = %c%s%c",
9110 				this_var->di_key,
9111 				(this_var->di_tv.v_type == VAR_STRING) ? '"'
9112 									: ' ',
9113 				p,
9114 				(this_var->di_tv.v_type == VAR_STRING) ? '"'
9115 								   : ' ') < 0)
9116 			|| put_eol(fd) == FAIL)
9117 		{
9118 		    vim_free(p);
9119 		    return FAIL;
9120 		}
9121 		vim_free(p);
9122 	    }
9123 #ifdef FEAT_FLOAT
9124 	    else if (this_var->di_tv.v_type == VAR_FLOAT
9125 		    && var_flavour(this_var->di_key) == VAR_FLAVOUR_SESSION)
9126 	    {
9127 		float_T f = this_var->di_tv.vval.v_float;
9128 		int sign = ' ';
9129 
9130 		if (f < 0)
9131 		{
9132 		    f = -f;
9133 		    sign = '-';
9134 		}
9135 		if ((fprintf(fd, "let %s = %c%f",
9136 					       this_var->di_key, sign, f) < 0)
9137 			|| put_eol(fd) == FAIL)
9138 		    return FAIL;
9139 	    }
9140 #endif
9141 	}
9142     }
9143     return OK;
9144 }
9145 #endif
9146 
9147 /*
9148  * Display script name where an item was last set.
9149  * Should only be invoked when 'verbose' is non-zero.
9150  */
9151     void
9152 last_set_msg(sctx_T script_ctx)
9153 {
9154     char_u *p;
9155 
9156     if (script_ctx.sc_sid != 0)
9157     {
9158 	p = home_replace_save(NULL, get_scriptname(script_ctx.sc_sid));
9159 	if (p != NULL)
9160 	{
9161 	    verbose_enter();
9162 	    MSG_PUTS(_("\n\tLast set from "));
9163 	    MSG_PUTS(p);
9164 	    if (script_ctx.sc_lnum > 0)
9165 	    {
9166 		MSG_PUTS(_(" line "));
9167 		msg_outnum((long)script_ctx.sc_lnum);
9168 	    }
9169 	    verbose_leave();
9170 	    vim_free(p);
9171 	}
9172     }
9173 }
9174 
9175 /* reset v:option_new, v:option_old and v:option_type */
9176     void
9177 reset_v_option_vars(void)
9178 {
9179     set_vim_var_string(VV_OPTION_NEW,  NULL, -1);
9180     set_vim_var_string(VV_OPTION_OLD,  NULL, -1);
9181     set_vim_var_string(VV_OPTION_TYPE, NULL, -1);
9182 }
9183 
9184 /*
9185  * Prepare "gap" for an assert error and add the sourcing position.
9186  */
9187     void
9188 prepare_assert_error(garray_T *gap)
9189 {
9190     char buf[NUMBUFLEN];
9191 
9192     ga_init2(gap, 1, 100);
9193     if (sourcing_name != NULL)
9194     {
9195 	ga_concat(gap, sourcing_name);
9196 	if (sourcing_lnum > 0)
9197 	    ga_concat(gap, (char_u *)" ");
9198     }
9199     if (sourcing_lnum > 0)
9200     {
9201 	sprintf(buf, "line %ld", (long)sourcing_lnum);
9202 	ga_concat(gap, (char_u *)buf);
9203     }
9204     if (sourcing_name != NULL || sourcing_lnum > 0)
9205 	ga_concat(gap, (char_u *)": ");
9206 }
9207 
9208 /*
9209  * Add an assert error to v:errors.
9210  */
9211     void
9212 assert_error(garray_T *gap)
9213 {
9214     struct vimvar   *vp = &vimvars[VV_ERRORS];
9215 
9216     if (vp->vv_type != VAR_LIST || vimvars[VV_ERRORS].vv_list == NULL)
9217 	/* Make sure v:errors is a list. */
9218 	set_vim_var_list(VV_ERRORS, list_alloc());
9219     list_append_string(vimvars[VV_ERRORS].vv_list, gap->ga_data, gap->ga_len);
9220 }
9221 
9222     int
9223 assert_equal_common(typval_T *argvars, assert_type_T atype)
9224 {
9225     garray_T	ga;
9226 
9227     if (tv_equal(&argvars[0], &argvars[1], FALSE, FALSE)
9228 						   != (atype == ASSERT_EQUAL))
9229     {
9230 	prepare_assert_error(&ga);
9231 	fill_assert_error(&ga, &argvars[2], NULL, &argvars[0], &argvars[1],
9232 								       atype);
9233 	assert_error(&ga);
9234 	ga_clear(&ga);
9235 	return 1;
9236     }
9237     return 0;
9238 }
9239 
9240     int
9241 assert_equalfile(typval_T *argvars)
9242 {
9243     char_u	buf1[NUMBUFLEN];
9244     char_u	buf2[NUMBUFLEN];
9245     char_u	*fname1 = tv_get_string_buf_chk(&argvars[0], buf1);
9246     char_u	*fname2 = tv_get_string_buf_chk(&argvars[1], buf2);
9247     garray_T	ga;
9248     FILE	*fd1;
9249     FILE	*fd2;
9250 
9251     if (fname1 == NULL || fname2 == NULL)
9252 	return 0;
9253 
9254     IObuff[0] = NUL;
9255     fd1 = mch_fopen((char *)fname1, READBIN);
9256     if (fd1 == NULL)
9257     {
9258 	vim_snprintf((char *)IObuff, IOSIZE, (char *)e_notread, fname1);
9259     }
9260     else
9261     {
9262 	fd2 = mch_fopen((char *)fname2, READBIN);
9263 	if (fd2 == NULL)
9264 	{
9265 	    fclose(fd1);
9266 	    vim_snprintf((char *)IObuff, IOSIZE, (char *)e_notread, fname2);
9267 	}
9268 	else
9269 	{
9270 	    int c1, c2;
9271 	    long count = 0;
9272 
9273 	    for (;;)
9274 	    {
9275 		c1 = fgetc(fd1);
9276 		c2 = fgetc(fd2);
9277 		if (c1 == EOF)
9278 		{
9279 		    if (c2 != EOF)
9280 			STRCPY(IObuff, "first file is shorter");
9281 		    break;
9282 		}
9283 		else if (c2 == EOF)
9284 		{
9285 		    STRCPY(IObuff, "second file is shorter");
9286 		    break;
9287 		}
9288 		else if (c1 != c2)
9289 		{
9290 		    vim_snprintf((char *)IObuff, IOSIZE,
9291 					      "difference at byte %ld", count);
9292 		    break;
9293 		}
9294 		++count;
9295 	    }
9296 	    fclose(fd1);
9297 	    fclose(fd2);
9298 	}
9299     }
9300     if (IObuff[0] != NUL)
9301     {
9302 	prepare_assert_error(&ga);
9303 	ga_concat(&ga, IObuff);
9304 	assert_error(&ga);
9305 	ga_clear(&ga);
9306 	return 1;
9307     }
9308     return 0;
9309 }
9310 
9311     int
9312 assert_match_common(typval_T *argvars, assert_type_T atype)
9313 {
9314     garray_T	ga;
9315     char_u	buf1[NUMBUFLEN];
9316     char_u	buf2[NUMBUFLEN];
9317     char_u	*pat = tv_get_string_buf_chk(&argvars[0], buf1);
9318     char_u	*text = tv_get_string_buf_chk(&argvars[1], buf2);
9319 
9320     if (pat == NULL || text == NULL)
9321 	emsg(_(e_invarg));
9322     else if (pattern_match(pat, text, FALSE) != (atype == ASSERT_MATCH))
9323     {
9324 	prepare_assert_error(&ga);
9325 	fill_assert_error(&ga, &argvars[2], NULL, &argvars[0], &argvars[1],
9326 									atype);
9327 	assert_error(&ga);
9328 	ga_clear(&ga);
9329 	return 1;
9330     }
9331     return 0;
9332 }
9333 
9334     int
9335 assert_inrange(typval_T *argvars)
9336 {
9337     garray_T	ga;
9338     int		error = FALSE;
9339     varnumber_T	lower = tv_get_number_chk(&argvars[0], &error);
9340     varnumber_T	upper = tv_get_number_chk(&argvars[1], &error);
9341     varnumber_T	actual = tv_get_number_chk(&argvars[2], &error);
9342     char_u	*tofree;
9343     char	msg[200];
9344     char_u	numbuf[NUMBUFLEN];
9345 
9346     if (error)
9347 	return 0;
9348     if (actual < lower || actual > upper)
9349     {
9350 	prepare_assert_error(&ga);
9351 	if (argvars[3].v_type != VAR_UNKNOWN)
9352 	{
9353 	    ga_concat(&ga, tv2string(&argvars[3], &tofree, numbuf, 0));
9354 	    vim_free(tofree);
9355 	}
9356 	else
9357 	{
9358 	    vim_snprintf(msg, 200, "Expected range %ld - %ld, but got %ld",
9359 				       (long)lower, (long)upper, (long)actual);
9360 	    ga_concat(&ga, (char_u *)msg);
9361 	}
9362 	assert_error(&ga);
9363 	ga_clear(&ga);
9364 	return 1;
9365     }
9366     return 0;
9367 }
9368 
9369 /*
9370  * Common for assert_true() and assert_false().
9371  * Return non-zero for failure.
9372  */
9373     int
9374 assert_bool(typval_T *argvars, int isTrue)
9375 {
9376     int		error = FALSE;
9377     garray_T	ga;
9378 
9379     if (argvars[0].v_type == VAR_SPECIAL
9380 	    && argvars[0].vval.v_number == (isTrue ? VVAL_TRUE : VVAL_FALSE))
9381 	return 0;
9382     if (argvars[0].v_type != VAR_NUMBER
9383 	    || (tv_get_number_chk(&argvars[0], &error) == 0) == isTrue
9384 	    || error)
9385     {
9386 	prepare_assert_error(&ga);
9387 	fill_assert_error(&ga, &argvars[1],
9388 		(char_u *)(isTrue ? "True" : "False"),
9389 		NULL, &argvars[0], ASSERT_OTHER);
9390 	assert_error(&ga);
9391 	ga_clear(&ga);
9392 	return 1;
9393     }
9394     return 0;
9395 }
9396 
9397     int
9398 assert_report(typval_T *argvars)
9399 {
9400     garray_T	ga;
9401 
9402     prepare_assert_error(&ga);
9403     ga_concat(&ga, tv_get_string(&argvars[0]));
9404     assert_error(&ga);
9405     ga_clear(&ga);
9406     return 1;
9407 }
9408 
9409     int
9410 assert_exception(typval_T *argvars)
9411 {
9412     garray_T	ga;
9413     char_u	*error = tv_get_string_chk(&argvars[0]);
9414 
9415     if (vimvars[VV_EXCEPTION].vv_str == NULL)
9416     {
9417 	prepare_assert_error(&ga);
9418 	ga_concat(&ga, (char_u *)"v:exception is not set");
9419 	assert_error(&ga);
9420 	ga_clear(&ga);
9421 	return 1;
9422     }
9423     else if (error != NULL
9424 	&& strstr((char *)vimvars[VV_EXCEPTION].vv_str, (char *)error) == NULL)
9425     {
9426 	prepare_assert_error(&ga);
9427 	fill_assert_error(&ga, &argvars[1], NULL, &argvars[0],
9428 				  &vimvars[VV_EXCEPTION].vv_tv, ASSERT_OTHER);
9429 	assert_error(&ga);
9430 	ga_clear(&ga);
9431 	return 1;
9432     }
9433     return 0;
9434 }
9435 
9436     int
9437 assert_beeps(typval_T *argvars)
9438 {
9439     char_u	*cmd = tv_get_string_chk(&argvars[0]);
9440     garray_T	ga;
9441     int		ret = 0;
9442 
9443     called_vim_beep = FALSE;
9444     suppress_errthrow = TRUE;
9445     emsg_silent = FALSE;
9446     do_cmdline_cmd(cmd);
9447     if (!called_vim_beep)
9448     {
9449 	prepare_assert_error(&ga);
9450 	ga_concat(&ga, (char_u *)"command did not beep: ");
9451 	ga_concat(&ga, cmd);
9452 	assert_error(&ga);
9453 	ga_clear(&ga);
9454 	ret = 1;
9455     }
9456 
9457     suppress_errthrow = FALSE;
9458     emsg_on_display = FALSE;
9459     return ret;
9460 }
9461 
9462     int
9463 assert_fails(typval_T *argvars)
9464 {
9465     char_u	*cmd = tv_get_string_chk(&argvars[0]);
9466     garray_T	ga;
9467     int		ret = 0;
9468     char_u	numbuf[NUMBUFLEN];
9469     char_u	*tofree;
9470 
9471     called_emsg = FALSE;
9472     suppress_errthrow = TRUE;
9473     emsg_silent = TRUE;
9474     do_cmdline_cmd(cmd);
9475     if (!called_emsg)
9476     {
9477 	prepare_assert_error(&ga);
9478 	ga_concat(&ga, (char_u *)"command did not fail: ");
9479 	if (argvars[1].v_type != VAR_UNKNOWN
9480 					   && argvars[2].v_type != VAR_UNKNOWN)
9481 	{
9482 	    ga_concat(&ga, echo_string(&argvars[2], &tofree, numbuf, 0));
9483 	    vim_free(tofree);
9484 	}
9485 	else
9486 	    ga_concat(&ga, cmd);
9487 	assert_error(&ga);
9488 	ga_clear(&ga);
9489 	ret = 1;
9490     }
9491     else if (argvars[1].v_type != VAR_UNKNOWN)
9492     {
9493 	char_u	buf[NUMBUFLEN];
9494 	char	*error = (char *)tv_get_string_buf_chk(&argvars[1], buf);
9495 
9496 	if (error == NULL
9497 		  || strstr((char *)vimvars[VV_ERRMSG].vv_str, error) == NULL)
9498 	{
9499 	    prepare_assert_error(&ga);
9500 	    fill_assert_error(&ga, &argvars[2], NULL, &argvars[1],
9501 				     &vimvars[VV_ERRMSG].vv_tv, ASSERT_OTHER);
9502 	    assert_error(&ga);
9503 	    ga_clear(&ga);
9504 	ret = 1;
9505 	}
9506     }
9507 
9508     called_emsg = FALSE;
9509     suppress_errthrow = FALSE;
9510     emsg_silent = FALSE;
9511     emsg_on_display = FALSE;
9512     set_vim_var_string(VV_ERRMSG, NULL, 0);
9513     return ret;
9514 }
9515 
9516 /*
9517  * Append "str" to "gap", escaping unprintable characters.
9518  * Changes NL to \n, CR to \r, etc.
9519  */
9520     static void
9521 ga_concat_esc(garray_T *gap, char_u *str)
9522 {
9523     char_u  *p;
9524     char_u  buf[NUMBUFLEN];
9525 
9526     if (str == NULL)
9527     {
9528 	ga_concat(gap, (char_u *)"NULL");
9529 	return;
9530     }
9531 
9532     for (p = str; *p != NUL; ++p)
9533 	switch (*p)
9534 	{
9535 	    case BS: ga_concat(gap, (char_u *)"\\b"); break;
9536 	    case ESC: ga_concat(gap, (char_u *)"\\e"); break;
9537 	    case FF: ga_concat(gap, (char_u *)"\\f"); break;
9538 	    case NL: ga_concat(gap, (char_u *)"\\n"); break;
9539 	    case TAB: ga_concat(gap, (char_u *)"\\t"); break;
9540 	    case CAR: ga_concat(gap, (char_u *)"\\r"); break;
9541 	    case '\\': ga_concat(gap, (char_u *)"\\\\"); break;
9542 	    default:
9543 		if (*p < ' ')
9544 		{
9545 		    vim_snprintf((char *)buf, NUMBUFLEN, "\\x%02x", *p);
9546 		    ga_concat(gap, buf);
9547 		}
9548 		else
9549 		    ga_append(gap, *p);
9550 		break;
9551 	}
9552 }
9553 
9554 /*
9555  * Fill "gap" with information about an assert error.
9556  */
9557     void
9558 fill_assert_error(
9559     garray_T	*gap,
9560     typval_T	*opt_msg_tv,
9561     char_u      *exp_str,
9562     typval_T	*exp_tv,
9563     typval_T	*got_tv,
9564     assert_type_T atype)
9565 {
9566     char_u	numbuf[NUMBUFLEN];
9567     char_u	*tofree;
9568 
9569     if (opt_msg_tv->v_type != VAR_UNKNOWN)
9570     {
9571 	ga_concat(gap, echo_string(opt_msg_tv, &tofree, numbuf, 0));
9572 	vim_free(tofree);
9573 	ga_concat(gap, (char_u *)": ");
9574     }
9575 
9576     if (atype == ASSERT_MATCH || atype == ASSERT_NOTMATCH)
9577 	ga_concat(gap, (char_u *)"Pattern ");
9578     else if (atype == ASSERT_NOTEQUAL)
9579 	ga_concat(gap, (char_u *)"Expected not equal to ");
9580     else
9581 	ga_concat(gap, (char_u *)"Expected ");
9582     if (exp_str == NULL)
9583     {
9584 	ga_concat_esc(gap, tv2string(exp_tv, &tofree, numbuf, 0));
9585 	vim_free(tofree);
9586     }
9587     else
9588 	ga_concat_esc(gap, exp_str);
9589     if (atype != ASSERT_NOTEQUAL)
9590     {
9591 	if (atype == ASSERT_MATCH)
9592 	    ga_concat(gap, (char_u *)" does not match ");
9593 	else if (atype == ASSERT_NOTMATCH)
9594 	    ga_concat(gap, (char_u *)" does match ");
9595 	else
9596 	    ga_concat(gap, (char_u *)" but got ");
9597 	ga_concat_esc(gap, tv2string(got_tv, &tofree, numbuf, 0));
9598 	vim_free(tofree);
9599     }
9600 }
9601 
9602 /*
9603  * Compare "typ1" and "typ2".  Put the result in "typ1".
9604  */
9605     int
9606 typval_compare(
9607     typval_T	*typ1,   /* first operand */
9608     typval_T	*typ2,   /* second operand */
9609     exptype_T	type,    /* operator */
9610     int		type_is, /* TRUE for "is" and "isnot" */
9611     int		ic)      /* ignore case */
9612 {
9613     int		i;
9614     varnumber_T	n1, n2;
9615     char_u	*s1, *s2;
9616     char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
9617 
9618     if (type_is && typ1->v_type != typ2->v_type)
9619     {
9620 	/* For "is" a different type always means FALSE, for "notis"
9621 	    * it means TRUE. */
9622 	n1 = (type == TYPE_NEQUAL);
9623     }
9624     else if (typ1->v_type == VAR_BLOB || typ2->v_type == VAR_BLOB)
9625     {
9626 	if (type_is)
9627 	{
9628 	    n1 = (typ1->v_type == typ2->v_type
9629 			    && typ1->vval.v_blob == typ2->vval.v_blob);
9630 	    if (type == TYPE_NEQUAL)
9631 		n1 = !n1;
9632 	}
9633 	else if (typ1->v_type != typ2->v_type
9634 		|| (type != TYPE_EQUAL && type != TYPE_NEQUAL))
9635 	{
9636 	    if (typ1->v_type != typ2->v_type)
9637 		emsg(_("E977: Can only compare Blob with Blob"));
9638 	    else
9639 		emsg(_(e_invalblob));
9640 	    clear_tv(typ1);
9641 	    return FAIL;
9642 	}
9643 	else
9644 	{
9645 	    // Compare two Blobs for being equal or unequal.
9646 	    n1 = blob_equal(typ1->vval.v_blob, typ2->vval.v_blob);
9647 	    if (type == TYPE_NEQUAL)
9648 		n1 = !n1;
9649 	}
9650     }
9651     else if (typ1->v_type == VAR_LIST || typ2->v_type == VAR_LIST)
9652     {
9653 	if (type_is)
9654 	{
9655 	    n1 = (typ1->v_type == typ2->v_type
9656 			    && typ1->vval.v_list == typ2->vval.v_list);
9657 	    if (type == TYPE_NEQUAL)
9658 		n1 = !n1;
9659 	}
9660 	else if (typ1->v_type != typ2->v_type
9661 		|| (type != TYPE_EQUAL && type != TYPE_NEQUAL))
9662 	{
9663 	    if (typ1->v_type != typ2->v_type)
9664 		emsg(_("E691: Can only compare List with List"));
9665 	    else
9666 		emsg(_("E692: Invalid operation for List"));
9667 	    clear_tv(typ1);
9668 	    return FAIL;
9669 	}
9670 	else
9671 	{
9672 	    /* Compare two Lists for being equal or unequal. */
9673 	    n1 = list_equal(typ1->vval.v_list, typ2->vval.v_list,
9674 							    ic, FALSE);
9675 	    if (type == TYPE_NEQUAL)
9676 		n1 = !n1;
9677 	}
9678     }
9679 
9680     else if (typ1->v_type == VAR_DICT || typ2->v_type == VAR_DICT)
9681     {
9682 	if (type_is)
9683 	{
9684 	    n1 = (typ1->v_type == typ2->v_type
9685 			    && typ1->vval.v_dict == typ2->vval.v_dict);
9686 	    if (type == TYPE_NEQUAL)
9687 		n1 = !n1;
9688 	}
9689 	else if (typ1->v_type != typ2->v_type
9690 		|| (type != TYPE_EQUAL && type != TYPE_NEQUAL))
9691 	{
9692 	    if (typ1->v_type != typ2->v_type)
9693 		emsg(_("E735: Can only compare Dictionary with Dictionary"));
9694 	    else
9695 		emsg(_("E736: Invalid operation for Dictionary"));
9696 	    clear_tv(typ1);
9697 	    return FAIL;
9698 	}
9699 	else
9700 	{
9701 	    /* Compare two Dictionaries for being equal or unequal. */
9702 	    n1 = dict_equal(typ1->vval.v_dict, typ2->vval.v_dict,
9703 							    ic, FALSE);
9704 	    if (type == TYPE_NEQUAL)
9705 		n1 = !n1;
9706 	}
9707     }
9708 
9709     else if (typ1->v_type == VAR_FUNC || typ2->v_type == VAR_FUNC
9710 	|| typ1->v_type == VAR_PARTIAL || typ2->v_type == VAR_PARTIAL)
9711     {
9712 	if (type != TYPE_EQUAL && type != TYPE_NEQUAL)
9713 	{
9714 	    emsg(_("E694: Invalid operation for Funcrefs"));
9715 	    clear_tv(typ1);
9716 	    return FAIL;
9717 	}
9718 	if ((typ1->v_type == VAR_PARTIAL
9719 					&& typ1->vval.v_partial == NULL)
9720 		|| (typ2->v_type == VAR_PARTIAL
9721 					&& typ2->vval.v_partial == NULL))
9722 	    /* when a partial is NULL assume not equal */
9723 	    n1 = FALSE;
9724 	else if (type_is)
9725 	{
9726 	    if (typ1->v_type == VAR_FUNC && typ2->v_type == VAR_FUNC)
9727 		/* strings are considered the same if their value is
9728 		    * the same */
9729 		n1 = tv_equal(typ1, typ2, ic, FALSE);
9730 	    else if (typ1->v_type == VAR_PARTIAL
9731 					&& typ2->v_type == VAR_PARTIAL)
9732 		n1 = (typ1->vval.v_partial == typ2->vval.v_partial);
9733 	    else
9734 		n1 = FALSE;
9735 	}
9736 	else
9737 	    n1 = tv_equal(typ1, typ2, ic, FALSE);
9738 	if (type == TYPE_NEQUAL)
9739 	    n1 = !n1;
9740     }
9741 
9742 #ifdef FEAT_FLOAT
9743     /*
9744 	* If one of the two variables is a float, compare as a float.
9745 	* When using "=~" or "!~", always compare as string.
9746 	*/
9747     else if ((typ1->v_type == VAR_FLOAT || typ2->v_type == VAR_FLOAT)
9748 	    && type != TYPE_MATCH && type != TYPE_NOMATCH)
9749     {
9750 	float_T f1, f2;
9751 
9752 	if (typ1->v_type == VAR_FLOAT)
9753 	    f1 = typ1->vval.v_float;
9754 	else
9755 	    f1 = tv_get_number(typ1);
9756 	if (typ2->v_type == VAR_FLOAT)
9757 	    f2 = typ2->vval.v_float;
9758 	else
9759 	    f2 = tv_get_number(typ2);
9760 	n1 = FALSE;
9761 	switch (type)
9762 	{
9763 	    case TYPE_EQUAL:    n1 = (f1 == f2); break;
9764 	    case TYPE_NEQUAL:   n1 = (f1 != f2); break;
9765 	    case TYPE_GREATER:  n1 = (f1 > f2); break;
9766 	    case TYPE_GEQUAL:   n1 = (f1 >= f2); break;
9767 	    case TYPE_SMALLER:  n1 = (f1 < f2); break;
9768 	    case TYPE_SEQUAL:   n1 = (f1 <= f2); break;
9769 	    case TYPE_UNKNOWN:
9770 	    case TYPE_MATCH:
9771 	    case TYPE_NOMATCH:  break;  /* avoid gcc warning */
9772 	}
9773     }
9774 #endif
9775 
9776     /*
9777 	* If one of the two variables is a number, compare as a number.
9778 	* When using "=~" or "!~", always compare as string.
9779 	*/
9780     else if ((typ1->v_type == VAR_NUMBER || typ2->v_type == VAR_NUMBER)
9781 	    && type != TYPE_MATCH && type != TYPE_NOMATCH)
9782     {
9783 	n1 = tv_get_number(typ1);
9784 	n2 = tv_get_number(typ2);
9785 	switch (type)
9786 	{
9787 	    case TYPE_EQUAL:    n1 = (n1 == n2); break;
9788 	    case TYPE_NEQUAL:   n1 = (n1 != n2); break;
9789 	    case TYPE_GREATER:  n1 = (n1 > n2); break;
9790 	    case TYPE_GEQUAL:   n1 = (n1 >= n2); break;
9791 	    case TYPE_SMALLER:  n1 = (n1 < n2); break;
9792 	    case TYPE_SEQUAL:   n1 = (n1 <= n2); break;
9793 	    case TYPE_UNKNOWN:
9794 	    case TYPE_MATCH:
9795 	    case TYPE_NOMATCH:  break;  /* avoid gcc warning */
9796 	}
9797     }
9798     else
9799     {
9800 	s1 = tv_get_string_buf(typ1, buf1);
9801 	s2 = tv_get_string_buf(typ2, buf2);
9802 	if (type != TYPE_MATCH && type != TYPE_NOMATCH)
9803 	    i = ic ? MB_STRICMP(s1, s2) : STRCMP(s1, s2);
9804 	else
9805 	    i = 0;
9806 	n1 = FALSE;
9807 	switch (type)
9808 	{
9809 	    case TYPE_EQUAL:    n1 = (i == 0); break;
9810 	    case TYPE_NEQUAL:   n1 = (i != 0); break;
9811 	    case TYPE_GREATER:  n1 = (i > 0); break;
9812 	    case TYPE_GEQUAL:   n1 = (i >= 0); break;
9813 	    case TYPE_SMALLER:  n1 = (i < 0); break;
9814 	    case TYPE_SEQUAL:   n1 = (i <= 0); break;
9815 
9816 	    case TYPE_MATCH:
9817 	    case TYPE_NOMATCH:
9818 		    n1 = pattern_match(s2, s1, ic);
9819 		    if (type == TYPE_NOMATCH)
9820 			n1 = !n1;
9821 		    break;
9822 
9823 	    case TYPE_UNKNOWN:  break;  /* avoid gcc warning */
9824 	}
9825     }
9826     clear_tv(typ1);
9827     typ1->v_type = VAR_NUMBER;
9828     typ1->vval.v_number = n1;
9829 
9830     return OK;
9831 }
9832 
9833     char_u *
9834 typval_tostring(typval_T *arg)
9835 {
9836     char_u	*tofree;
9837     char_u	numbuf[NUMBUFLEN];
9838     char_u	*ret = NULL;
9839 
9840     if (arg == NULL)
9841 	return vim_strsave((char_u *)"(does not exist)");
9842     ret = tv2string(arg, &tofree, numbuf, 0);
9843     /* Make a copy if we have a value but it's not in allocated memory. */
9844     if (ret != NULL && tofree == NULL)
9845 	ret = vim_strsave(ret);
9846     return ret;
9847 }
9848 
9849     int
9850 var_exists(char_u *var)
9851 {
9852     char_u	*name;
9853     char_u	*tofree;
9854     typval_T    tv;
9855     int		len = 0;
9856     int		n = FALSE;
9857 
9858     /* get_name_len() takes care of expanding curly braces */
9859     name = var;
9860     len = get_name_len(&var, &tofree, TRUE, FALSE);
9861     if (len > 0)
9862     {
9863 	if (tofree != NULL)
9864 	    name = tofree;
9865 	n = (get_var_tv(name, len, &tv, NULL, FALSE, TRUE) == OK);
9866 	if (n)
9867 	{
9868 	    /* handle d.key, l[idx], f(expr) */
9869 	    n = (handle_subscript(&var, &tv, TRUE, FALSE) == OK);
9870 	    if (n)
9871 		clear_tv(&tv);
9872 	}
9873     }
9874     if (*var != NUL)
9875 	n = FALSE;
9876 
9877     vim_free(tofree);
9878     return n;
9879 }
9880 
9881 #endif /* FEAT_EVAL */
9882 
9883 
9884 #if defined(FEAT_MODIFY_FNAME) || defined(FEAT_EVAL) || defined(PROTO)
9885 
9886 #ifdef WIN3264
9887 /*
9888  * Functions for ":8" filename modifier: get 8.3 version of a filename.
9889  */
9890 
9891 /*
9892  * Get the short path (8.3) for the filename in "fnamep".
9893  * Only works for a valid file name.
9894  * When the path gets longer "fnamep" is changed and the allocated buffer
9895  * is put in "bufp".
9896  * *fnamelen is the length of "fnamep" and set to 0 for a nonexistent path.
9897  * Returns OK on success, FAIL on failure.
9898  */
9899     static int
9900 get_short_pathname(char_u **fnamep, char_u **bufp, int *fnamelen)
9901 {
9902     int		l, len;
9903     char_u	*newbuf;
9904 
9905     len = *fnamelen;
9906     l = GetShortPathName((LPSTR)*fnamep, (LPSTR)*fnamep, len);
9907     if (l > len - 1)
9908     {
9909 	/* If that doesn't work (not enough space), then save the string
9910 	 * and try again with a new buffer big enough. */
9911 	newbuf = vim_strnsave(*fnamep, l);
9912 	if (newbuf == NULL)
9913 	    return FAIL;
9914 
9915 	vim_free(*bufp);
9916 	*fnamep = *bufp = newbuf;
9917 
9918 	/* Really should always succeed, as the buffer is big enough. */
9919 	l = GetShortPathName((LPSTR)*fnamep, (LPSTR)*fnamep, l+1);
9920     }
9921 
9922     *fnamelen = l;
9923     return OK;
9924 }
9925 
9926 /*
9927  * Get the short path (8.3) for the filename in "fname". The converted
9928  * path is returned in "bufp".
9929  *
9930  * Some of the directories specified in "fname" may not exist. This function
9931  * will shorten the existing directories at the beginning of the path and then
9932  * append the remaining non-existing path.
9933  *
9934  * fname - Pointer to the filename to shorten.  On return, contains the
9935  *	   pointer to the shortened pathname
9936  * bufp -  Pointer to an allocated buffer for the filename.
9937  * fnamelen - Length of the filename pointed to by fname
9938  *
9939  * Returns OK on success (or nothing done) and FAIL on failure (out of memory).
9940  */
9941     static int
9942 shortpath_for_invalid_fname(
9943     char_u	**fname,
9944     char_u	**bufp,
9945     int		*fnamelen)
9946 {
9947     char_u	*short_fname, *save_fname, *pbuf_unused;
9948     char_u	*endp, *save_endp;
9949     char_u	ch;
9950     int		old_len, len;
9951     int		new_len, sfx_len;
9952     int		retval = OK;
9953 
9954     /* Make a copy */
9955     old_len = *fnamelen;
9956     save_fname = vim_strnsave(*fname, old_len);
9957     pbuf_unused = NULL;
9958     short_fname = NULL;
9959 
9960     endp = save_fname + old_len - 1; /* Find the end of the copy */
9961     save_endp = endp;
9962 
9963     /*
9964      * Try shortening the supplied path till it succeeds by removing one
9965      * directory at a time from the tail of the path.
9966      */
9967     len = 0;
9968     for (;;)
9969     {
9970 	/* go back one path-separator */
9971 	while (endp > save_fname && !after_pathsep(save_fname, endp + 1))
9972 	    --endp;
9973 	if (endp <= save_fname)
9974 	    break;		/* processed the complete path */
9975 
9976 	/*
9977 	 * Replace the path separator with a NUL and try to shorten the
9978 	 * resulting path.
9979 	 */
9980 	ch = *endp;
9981 	*endp = 0;
9982 	short_fname = save_fname;
9983 	len = (int)STRLEN(short_fname) + 1;
9984 	if (get_short_pathname(&short_fname, &pbuf_unused, &len) == FAIL)
9985 	{
9986 	    retval = FAIL;
9987 	    goto theend;
9988 	}
9989 	*endp = ch;	/* preserve the string */
9990 
9991 	if (len > 0)
9992 	    break;	/* successfully shortened the path */
9993 
9994 	/* failed to shorten the path. Skip the path separator */
9995 	--endp;
9996     }
9997 
9998     if (len > 0)
9999     {
10000 	/*
10001 	 * Succeeded in shortening the path. Now concatenate the shortened
10002 	 * path with the remaining path at the tail.
10003 	 */
10004 
10005 	/* Compute the length of the new path. */
10006 	sfx_len = (int)(save_endp - endp) + 1;
10007 	new_len = len + sfx_len;
10008 
10009 	*fnamelen = new_len;
10010 	vim_free(*bufp);
10011 	if (new_len > old_len)
10012 	{
10013 	    /* There is not enough space in the currently allocated string,
10014 	     * copy it to a buffer big enough. */
10015 	    *fname = *bufp = vim_strnsave(short_fname, new_len);
10016 	    if (*fname == NULL)
10017 	    {
10018 		retval = FAIL;
10019 		goto theend;
10020 	    }
10021 	}
10022 	else
10023 	{
10024 	    /* Transfer short_fname to the main buffer (it's big enough),
10025 	     * unless get_short_pathname() did its work in-place. */
10026 	    *fname = *bufp = save_fname;
10027 	    if (short_fname != save_fname)
10028 		vim_strncpy(save_fname, short_fname, len);
10029 	    save_fname = NULL;
10030 	}
10031 
10032 	/* concat the not-shortened part of the path */
10033 	vim_strncpy(*fname + len, endp, sfx_len);
10034 	(*fname)[new_len] = NUL;
10035     }
10036 
10037 theend:
10038     vim_free(pbuf_unused);
10039     vim_free(save_fname);
10040 
10041     return retval;
10042 }
10043 
10044 /*
10045  * Get a pathname for a partial path.
10046  * Returns OK for success, FAIL for failure.
10047  */
10048     static int
10049 shortpath_for_partial(
10050     char_u	**fnamep,
10051     char_u	**bufp,
10052     int		*fnamelen)
10053 {
10054     int		sepcount, len, tflen;
10055     char_u	*p;
10056     char_u	*pbuf, *tfname;
10057     int		hasTilde;
10058 
10059     /* Count up the path separators from the RHS.. so we know which part
10060      * of the path to return. */
10061     sepcount = 0;
10062     for (p = *fnamep; p < *fnamep + *fnamelen; MB_PTR_ADV(p))
10063 	if (vim_ispathsep(*p))
10064 	    ++sepcount;
10065 
10066     /* Need full path first (use expand_env() to remove a "~/") */
10067     hasTilde = (**fnamep == '~');
10068     if (hasTilde)
10069 	pbuf = tfname = expand_env_save(*fnamep);
10070     else
10071 	pbuf = tfname = FullName_save(*fnamep, FALSE);
10072 
10073     len = tflen = (int)STRLEN(tfname);
10074 
10075     if (get_short_pathname(&tfname, &pbuf, &len) == FAIL)
10076 	return FAIL;
10077 
10078     if (len == 0)
10079     {
10080 	/* Don't have a valid filename, so shorten the rest of the
10081 	 * path if we can. This CAN give us invalid 8.3 filenames, but
10082 	 * there's not a lot of point in guessing what it might be.
10083 	 */
10084 	len = tflen;
10085 	if (shortpath_for_invalid_fname(&tfname, &pbuf, &len) == FAIL)
10086 	    return FAIL;
10087     }
10088 
10089     /* Count the paths backward to find the beginning of the desired string. */
10090     for (p = tfname + len - 1; p >= tfname; --p)
10091     {
10092 #ifdef FEAT_MBYTE
10093 	if (has_mbyte)
10094 	    p -= mb_head_off(tfname, p);
10095 #endif
10096 	if (vim_ispathsep(*p))
10097 	{
10098 	    if (sepcount == 0 || (hasTilde && sepcount == 1))
10099 		break;
10100 	    else
10101 		sepcount --;
10102 	}
10103     }
10104     if (hasTilde)
10105     {
10106 	--p;
10107 	if (p >= tfname)
10108 	    *p = '~';
10109 	else
10110 	    return FAIL;
10111     }
10112     else
10113 	++p;
10114 
10115     /* Copy in the string - p indexes into tfname - allocated at pbuf */
10116     vim_free(*bufp);
10117     *fnamelen = (int)STRLEN(p);
10118     *bufp = pbuf;
10119     *fnamep = p;
10120 
10121     return OK;
10122 }
10123 #endif /* WIN3264 */
10124 
10125 /*
10126  * Adjust a filename, according to a string of modifiers.
10127  * *fnamep must be NUL terminated when called.  When returning, the length is
10128  * determined by *fnamelen.
10129  * Returns VALID_ flags or -1 for failure.
10130  * When there is an error, *fnamep is set to NULL.
10131  */
10132     int
10133 modify_fname(
10134     char_u	*src,		// string with modifiers
10135     int		tilde_file,	// "~" is a file name, not $HOME
10136     int		*usedlen,	// characters after src that are used
10137     char_u	**fnamep,	// file name so far
10138     char_u	**bufp,		// buffer for allocated file name or NULL
10139     int		*fnamelen)	// length of fnamep
10140 {
10141     int		valid = 0;
10142     char_u	*tail;
10143     char_u	*s, *p, *pbuf;
10144     char_u	dirname[MAXPATHL];
10145     int		c;
10146     int		has_fullname = 0;
10147 #ifdef WIN3264
10148     char_u	*fname_start = *fnamep;
10149     int		has_shortname = 0;
10150 #endif
10151 
10152 repeat:
10153     /* ":p" - full path/file_name */
10154     if (src[*usedlen] == ':' && src[*usedlen + 1] == 'p')
10155     {
10156 	has_fullname = 1;
10157 
10158 	valid |= VALID_PATH;
10159 	*usedlen += 2;
10160 
10161 	/* Expand "~/path" for all systems and "~user/path" for Unix and VMS */
10162 	if ((*fnamep)[0] == '~'
10163 #if !defined(UNIX) && !(defined(VMS) && defined(USER_HOME))
10164 		&& ((*fnamep)[1] == '/'
10165 # ifdef BACKSLASH_IN_FILENAME
10166 		    || (*fnamep)[1] == '\\'
10167 # endif
10168 		    || (*fnamep)[1] == NUL)
10169 #endif
10170 		&& !(tilde_file && (*fnamep)[1] == NUL)
10171 	   )
10172 	{
10173 	    *fnamep = expand_env_save(*fnamep);
10174 	    vim_free(*bufp);	/* free any allocated file name */
10175 	    *bufp = *fnamep;
10176 	    if (*fnamep == NULL)
10177 		return -1;
10178 	}
10179 
10180 	/* When "/." or "/.." is used: force expansion to get rid of it. */
10181 	for (p = *fnamep; *p != NUL; MB_PTR_ADV(p))
10182 	{
10183 	    if (vim_ispathsep(*p)
10184 		    && p[1] == '.'
10185 		    && (p[2] == NUL
10186 			|| vim_ispathsep(p[2])
10187 			|| (p[2] == '.'
10188 			    && (p[3] == NUL || vim_ispathsep(p[3])))))
10189 		break;
10190 	}
10191 
10192 	/* FullName_save() is slow, don't use it when not needed. */
10193 	if (*p != NUL || !vim_isAbsName(*fnamep))
10194 	{
10195 	    *fnamep = FullName_save(*fnamep, *p != NUL);
10196 	    vim_free(*bufp);	/* free any allocated file name */
10197 	    *bufp = *fnamep;
10198 	    if (*fnamep == NULL)
10199 		return -1;
10200 	}
10201 
10202 #ifdef WIN3264
10203 # if _WIN32_WINNT >= 0x0500
10204 	if (vim_strchr(*fnamep, '~') != NULL)
10205 	{
10206 	    /* Expand 8.3 filename to full path.  Needed to make sure the same
10207 	     * file does not have two different names.
10208 	     * Note: problem does not occur if _WIN32_WINNT < 0x0500. */
10209 	    p = alloc(_MAX_PATH + 1);
10210 	    if (p != NULL)
10211 	    {
10212 		if (GetLongPathName((LPSTR)*fnamep, (LPSTR)p, _MAX_PATH))
10213 		{
10214 		    vim_free(*bufp);
10215 		    *bufp = *fnamep = p;
10216 		}
10217 		else
10218 		    vim_free(p);
10219 	    }
10220 	}
10221 # endif
10222 #endif
10223 	/* Append a path separator to a directory. */
10224 	if (mch_isdir(*fnamep))
10225 	{
10226 	    /* Make room for one or two extra characters. */
10227 	    *fnamep = vim_strnsave(*fnamep, (int)STRLEN(*fnamep) + 2);
10228 	    vim_free(*bufp);	/* free any allocated file name */
10229 	    *bufp = *fnamep;
10230 	    if (*fnamep == NULL)
10231 		return -1;
10232 	    add_pathsep(*fnamep);
10233 	}
10234     }
10235 
10236     /* ":." - path relative to the current directory */
10237     /* ":~" - path relative to the home directory */
10238     /* ":8" - shortname path - postponed till after */
10239     while (src[*usedlen] == ':'
10240 		  && ((c = src[*usedlen + 1]) == '.' || c == '~' || c == '8'))
10241     {
10242 	*usedlen += 2;
10243 	if (c == '8')
10244 	{
10245 #ifdef WIN3264
10246 	    has_shortname = 1; /* Postpone this. */
10247 #endif
10248 	    continue;
10249 	}
10250 	pbuf = NULL;
10251 	/* Need full path first (use expand_env() to remove a "~/") */
10252 	if (!has_fullname)
10253 	{
10254 	    if (c == '.' && **fnamep == '~')
10255 		p = pbuf = expand_env_save(*fnamep);
10256 	    else
10257 		p = pbuf = FullName_save(*fnamep, FALSE);
10258 	}
10259 	else
10260 	    p = *fnamep;
10261 
10262 	has_fullname = 0;
10263 
10264 	if (p != NULL)
10265 	{
10266 	    if (c == '.')
10267 	    {
10268 		mch_dirname(dirname, MAXPATHL);
10269 		s = shorten_fname(p, dirname);
10270 		if (s != NULL)
10271 		{
10272 		    *fnamep = s;
10273 		    if (pbuf != NULL)
10274 		    {
10275 			vim_free(*bufp);   /* free any allocated file name */
10276 			*bufp = pbuf;
10277 			pbuf = NULL;
10278 		    }
10279 		}
10280 	    }
10281 	    else
10282 	    {
10283 		home_replace(NULL, p, dirname, MAXPATHL, TRUE);
10284 		/* Only replace it when it starts with '~' */
10285 		if (*dirname == '~')
10286 		{
10287 		    s = vim_strsave(dirname);
10288 		    if (s != NULL)
10289 		    {
10290 			*fnamep = s;
10291 			vim_free(*bufp);
10292 			*bufp = s;
10293 		    }
10294 		}
10295 	    }
10296 	    vim_free(pbuf);
10297 	}
10298     }
10299 
10300     tail = gettail(*fnamep);
10301     *fnamelen = (int)STRLEN(*fnamep);
10302 
10303     /* ":h" - head, remove "/file_name", can be repeated  */
10304     /* Don't remove the first "/" or "c:\" */
10305     while (src[*usedlen] == ':' && src[*usedlen + 1] == 'h')
10306     {
10307 	valid |= VALID_HEAD;
10308 	*usedlen += 2;
10309 	s = get_past_head(*fnamep);
10310 	while (tail > s && after_pathsep(s, tail))
10311 	    MB_PTR_BACK(*fnamep, tail);
10312 	*fnamelen = (int)(tail - *fnamep);
10313 #ifdef VMS
10314 	if (*fnamelen > 0)
10315 	    *fnamelen += 1; /* the path separator is part of the path */
10316 #endif
10317 	if (*fnamelen == 0)
10318 	{
10319 	    /* Result is empty.  Turn it into "." to make ":cd %:h" work. */
10320 	    p = vim_strsave((char_u *)".");
10321 	    if (p == NULL)
10322 		return -1;
10323 	    vim_free(*bufp);
10324 	    *bufp = *fnamep = tail = p;
10325 	    *fnamelen = 1;
10326 	}
10327 	else
10328 	{
10329 	    while (tail > s && !after_pathsep(s, tail))
10330 		MB_PTR_BACK(*fnamep, tail);
10331 	}
10332     }
10333 
10334     /* ":8" - shortname  */
10335     if (src[*usedlen] == ':' && src[*usedlen + 1] == '8')
10336     {
10337 	*usedlen += 2;
10338 #ifdef WIN3264
10339 	has_shortname = 1;
10340 #endif
10341     }
10342 
10343 #ifdef WIN3264
10344     /*
10345      * Handle ":8" after we have done 'heads' and before we do 'tails'.
10346      */
10347     if (has_shortname)
10348     {
10349 	/* Copy the string if it is shortened by :h and when it wasn't copied
10350 	 * yet, because we are going to change it in place.  Avoids changing
10351 	 * the buffer name for "%:8". */
10352 	if (*fnamelen < (int)STRLEN(*fnamep) || *fnamep == fname_start)
10353 	{
10354 	    p = vim_strnsave(*fnamep, *fnamelen);
10355 	    if (p == NULL)
10356 		return -1;
10357 	    vim_free(*bufp);
10358 	    *bufp = *fnamep = p;
10359 	}
10360 
10361 	/* Split into two implementations - makes it easier.  First is where
10362 	 * there isn't a full name already, second is where there is. */
10363 	if (!has_fullname && !vim_isAbsName(*fnamep))
10364 	{
10365 	    if (shortpath_for_partial(fnamep, bufp, fnamelen) == FAIL)
10366 		return -1;
10367 	}
10368 	else
10369 	{
10370 	    int		l = *fnamelen;
10371 
10372 	    /* Simple case, already have the full-name.
10373 	     * Nearly always shorter, so try first time. */
10374 	    if (get_short_pathname(fnamep, bufp, &l) == FAIL)
10375 		return -1;
10376 
10377 	    if (l == 0)
10378 	    {
10379 		/* Couldn't find the filename, search the paths. */
10380 		l = *fnamelen;
10381 		if (shortpath_for_invalid_fname(fnamep, bufp, &l) == FAIL)
10382 		    return -1;
10383 	    }
10384 	    *fnamelen = l;
10385 	}
10386     }
10387 #endif /* WIN3264 */
10388 
10389     /* ":t" - tail, just the basename */
10390     if (src[*usedlen] == ':' && src[*usedlen + 1] == 't')
10391     {
10392 	*usedlen += 2;
10393 	*fnamelen -= (int)(tail - *fnamep);
10394 	*fnamep = tail;
10395     }
10396 
10397     /* ":e" - extension, can be repeated */
10398     /* ":r" - root, without extension, can be repeated */
10399     while (src[*usedlen] == ':'
10400 	    && (src[*usedlen + 1] == 'e' || src[*usedlen + 1] == 'r'))
10401     {
10402 	/* find a '.' in the tail:
10403 	 * - for second :e: before the current fname
10404 	 * - otherwise: The last '.'
10405 	 */
10406 	if (src[*usedlen + 1] == 'e' && *fnamep > tail)
10407 	    s = *fnamep - 2;
10408 	else
10409 	    s = *fnamep + *fnamelen - 1;
10410 	for ( ; s > tail; --s)
10411 	    if (s[0] == '.')
10412 		break;
10413 	if (src[*usedlen + 1] == 'e')		/* :e */
10414 	{
10415 	    if (s > tail)
10416 	    {
10417 		*fnamelen += (int)(*fnamep - (s + 1));
10418 		*fnamep = s + 1;
10419 #ifdef VMS
10420 		/* cut version from the extension */
10421 		s = *fnamep + *fnamelen - 1;
10422 		for ( ; s > *fnamep; --s)
10423 		    if (s[0] == ';')
10424 			break;
10425 		if (s > *fnamep)
10426 		    *fnamelen = s - *fnamep;
10427 #endif
10428 	    }
10429 	    else if (*fnamep <= tail)
10430 		*fnamelen = 0;
10431 	}
10432 	else				/* :r */
10433 	{
10434 	    if (s > tail)	/* remove one extension */
10435 		*fnamelen = (int)(s - *fnamep);
10436 	}
10437 	*usedlen += 2;
10438     }
10439 
10440     /* ":s?pat?foo?" - substitute */
10441     /* ":gs?pat?foo?" - global substitute */
10442     if (src[*usedlen] == ':'
10443 	    && (src[*usedlen + 1] == 's'
10444 		|| (src[*usedlen + 1] == 'g' && src[*usedlen + 2] == 's')))
10445     {
10446 	char_u	    *str;
10447 	char_u	    *pat;
10448 	char_u	    *sub;
10449 	int	    sep;
10450 	char_u	    *flags;
10451 	int	    didit = FALSE;
10452 
10453 	flags = (char_u *)"";
10454 	s = src + *usedlen + 2;
10455 	if (src[*usedlen + 1] == 'g')
10456 	{
10457 	    flags = (char_u *)"g";
10458 	    ++s;
10459 	}
10460 
10461 	sep = *s++;
10462 	if (sep)
10463 	{
10464 	    /* find end of pattern */
10465 	    p = vim_strchr(s, sep);
10466 	    if (p != NULL)
10467 	    {
10468 		pat = vim_strnsave(s, (int)(p - s));
10469 		if (pat != NULL)
10470 		{
10471 		    s = p + 1;
10472 		    /* find end of substitution */
10473 		    p = vim_strchr(s, sep);
10474 		    if (p != NULL)
10475 		    {
10476 			sub = vim_strnsave(s, (int)(p - s));
10477 			str = vim_strnsave(*fnamep, *fnamelen);
10478 			if (sub != NULL && str != NULL)
10479 			{
10480 			    *usedlen = (int)(p + 1 - src);
10481 			    s = do_string_sub(str, pat, sub, NULL, flags);
10482 			    if (s != NULL)
10483 			    {
10484 				*fnamep = s;
10485 				*fnamelen = (int)STRLEN(s);
10486 				vim_free(*bufp);
10487 				*bufp = s;
10488 				didit = TRUE;
10489 			    }
10490 			}
10491 			vim_free(sub);
10492 			vim_free(str);
10493 		    }
10494 		    vim_free(pat);
10495 		}
10496 	    }
10497 	    /* after using ":s", repeat all the modifiers */
10498 	    if (didit)
10499 		goto repeat;
10500 	}
10501     }
10502 
10503     if (src[*usedlen] == ':' && src[*usedlen + 1] == 'S')
10504     {
10505 	/* vim_strsave_shellescape() needs a NUL terminated string. */
10506 	c = (*fnamep)[*fnamelen];
10507 	if (c != NUL)
10508 	    (*fnamep)[*fnamelen] = NUL;
10509 	p = vim_strsave_shellescape(*fnamep, FALSE, FALSE);
10510 	if (c != NUL)
10511 	    (*fnamep)[*fnamelen] = c;
10512 	if (p == NULL)
10513 	    return -1;
10514 	vim_free(*bufp);
10515 	*bufp = *fnamep = p;
10516 	*fnamelen = (int)STRLEN(p);
10517 	*usedlen += 2;
10518     }
10519 
10520     return valid;
10521 }
10522 
10523 /*
10524  * Perform a substitution on "str" with pattern "pat" and substitute "sub".
10525  * When "sub" is NULL "expr" is used, must be a VAR_FUNC or VAR_PARTIAL.
10526  * "flags" can be "g" to do a global substitute.
10527  * Returns an allocated string, NULL for error.
10528  */
10529     char_u *
10530 do_string_sub(
10531     char_u	*str,
10532     char_u	*pat,
10533     char_u	*sub,
10534     typval_T	*expr,
10535     char_u	*flags)
10536 {
10537     int		sublen;
10538     regmatch_T	regmatch;
10539     int		i;
10540     int		do_all;
10541     char_u	*tail;
10542     char_u	*end;
10543     garray_T	ga;
10544     char_u	*ret;
10545     char_u	*save_cpo;
10546     char_u	*zero_width = NULL;
10547 
10548     /* Make 'cpoptions' empty, so that the 'l' flag doesn't work here */
10549     save_cpo = p_cpo;
10550     p_cpo = empty_option;
10551 
10552     ga_init2(&ga, 1, 200);
10553 
10554     do_all = (flags[0] == 'g');
10555 
10556     regmatch.rm_ic = p_ic;
10557     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
10558     if (regmatch.regprog != NULL)
10559     {
10560 	tail = str;
10561 	end = str + STRLEN(str);
10562 	while (vim_regexec_nl(&regmatch, str, (colnr_T)(tail - str)))
10563 	{
10564 	    /* Skip empty match except for first match. */
10565 	    if (regmatch.startp[0] == regmatch.endp[0])
10566 	    {
10567 		if (zero_width == regmatch.startp[0])
10568 		{
10569 		    /* avoid getting stuck on a match with an empty string */
10570 		    i = MB_PTR2LEN(tail);
10571 		    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail,
10572 								   (size_t)i);
10573 		    ga.ga_len += i;
10574 		    tail += i;
10575 		    continue;
10576 		}
10577 		zero_width = regmatch.startp[0];
10578 	    }
10579 
10580 	    /*
10581 	     * Get some space for a temporary buffer to do the substitution
10582 	     * into.  It will contain:
10583 	     * - The text up to where the match is.
10584 	     * - The substituted text.
10585 	     * - The text after the match.
10586 	     */
10587 	    sublen = vim_regsub(&regmatch, sub, expr, tail, FALSE, TRUE, FALSE);
10588 	    if (ga_grow(&ga, (int)((end - tail) + sublen -
10589 			    (regmatch.endp[0] - regmatch.startp[0]))) == FAIL)
10590 	    {
10591 		ga_clear(&ga);
10592 		break;
10593 	    }
10594 
10595 	    /* copy the text up to where the match is */
10596 	    i = (int)(regmatch.startp[0] - tail);
10597 	    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail, (size_t)i);
10598 	    /* add the substituted text */
10599 	    (void)vim_regsub(&regmatch, sub, expr, (char_u *)ga.ga_data
10600 					  + ga.ga_len + i, TRUE, TRUE, FALSE);
10601 	    ga.ga_len += i + sublen - 1;
10602 	    tail = regmatch.endp[0];
10603 	    if (*tail == NUL)
10604 		break;
10605 	    if (!do_all)
10606 		break;
10607 	}
10608 
10609 	if (ga.ga_data != NULL)
10610 	    STRCPY((char *)ga.ga_data + ga.ga_len, tail);
10611 
10612 	vim_regfree(regmatch.regprog);
10613     }
10614 
10615     ret = vim_strsave(ga.ga_data == NULL ? str : (char_u *)ga.ga_data);
10616     ga_clear(&ga);
10617     if (p_cpo == empty_option)
10618 	p_cpo = save_cpo;
10619     else
10620 	/* Darn, evaluating {sub} expression or {expr} changed the value. */
10621 	free_string_option(save_cpo);
10622 
10623     return ret;
10624 }
10625 
10626     static int
10627 filter_map_one(typval_T *tv, typval_T *expr, int map, int *remp)
10628 {
10629     typval_T	rettv;
10630     typval_T	argv[3];
10631     int		retval = FAIL;
10632 
10633     copy_tv(tv, &vimvars[VV_VAL].vv_tv);
10634     argv[0] = vimvars[VV_KEY].vv_tv;
10635     argv[1] = vimvars[VV_VAL].vv_tv;
10636     if (eval_expr_typval(expr, argv, 2, &rettv) == FAIL)
10637 	goto theend;
10638     if (map)
10639     {
10640 	/* map(): replace the list item value */
10641 	clear_tv(tv);
10642 	rettv.v_lock = 0;
10643 	*tv = rettv;
10644     }
10645     else
10646     {
10647 	int	    error = FALSE;
10648 
10649 	/* filter(): when expr is zero remove the item */
10650 	*remp = (tv_get_number_chk(&rettv, &error) == 0);
10651 	clear_tv(&rettv);
10652 	/* On type error, nothing has been removed; return FAIL to stop the
10653 	 * loop.  The error message was given by tv_get_number_chk(). */
10654 	if (error)
10655 	    goto theend;
10656     }
10657     retval = OK;
10658 theend:
10659     clear_tv(&vimvars[VV_VAL].vv_tv);
10660     return retval;
10661 }
10662 
10663 
10664 /*
10665  * Implementation of map() and filter().
10666  */
10667     void
10668 filter_map(typval_T *argvars, typval_T *rettv, int map)
10669 {
10670     typval_T	*expr;
10671     listitem_T	*li, *nli;
10672     list_T	*l = NULL;
10673     dictitem_T	*di;
10674     hashtab_T	*ht;
10675     hashitem_T	*hi;
10676     dict_T	*d = NULL;
10677     typval_T	save_val;
10678     typval_T	save_key;
10679     blob_T	*b = NULL;
10680     int		rem;
10681     int		todo;
10682     char_u	*ermsg = (char_u *)(map ? "map()" : "filter()");
10683     char_u	*arg_errmsg = (char_u *)(map ? N_("map() argument")
10684 				   : N_("filter() argument"));
10685     int		save_did_emsg;
10686     int		idx = 0;
10687 
10688     if (argvars[0].v_type == VAR_BLOB)
10689     {
10690 	if ((b = argvars[0].vval.v_blob) == NULL)
10691 	    return;
10692     }
10693     else if (argvars[0].v_type == VAR_LIST)
10694     {
10695 	if ((l = argvars[0].vval.v_list) == NULL
10696 	      || (!map && tv_check_lock(l->lv_lock, arg_errmsg, TRUE)))
10697 	    return;
10698     }
10699     else if (argvars[0].v_type == VAR_DICT)
10700     {
10701 	if ((d = argvars[0].vval.v_dict) == NULL
10702 	      || (!map && tv_check_lock(d->dv_lock, arg_errmsg, TRUE)))
10703 	    return;
10704     }
10705     else
10706     {
10707 	semsg(_(e_listdictarg), ermsg);
10708 	return;
10709     }
10710 
10711     expr = &argvars[1];
10712     /* On type errors, the preceding call has already displayed an error
10713      * message.  Avoid a misleading error message for an empty string that
10714      * was not passed as argument. */
10715     if (expr->v_type != VAR_UNKNOWN)
10716     {
10717 	prepare_vimvar(VV_VAL, &save_val);
10718 
10719 	/* We reset "did_emsg" to be able to detect whether an error
10720 	 * occurred during evaluation of the expression. */
10721 	save_did_emsg = did_emsg;
10722 	did_emsg = FALSE;
10723 
10724 	prepare_vimvar(VV_KEY, &save_key);
10725 	if (argvars[0].v_type == VAR_DICT)
10726 	{
10727 	    vimvars[VV_KEY].vv_type = VAR_STRING;
10728 
10729 	    ht = &d->dv_hashtab;
10730 	    hash_lock(ht);
10731 	    todo = (int)ht->ht_used;
10732 	    for (hi = ht->ht_array; todo > 0; ++hi)
10733 	    {
10734 		if (!HASHITEM_EMPTY(hi))
10735 		{
10736 		    int r;
10737 
10738 		    --todo;
10739 		    di = HI2DI(hi);
10740 		    if (map &&
10741 			    (tv_check_lock(di->di_tv.v_lock, arg_errmsg, TRUE)
10742 			    || var_check_ro(di->di_flags, arg_errmsg, TRUE)))
10743 			break;
10744 		    vimvars[VV_KEY].vv_str = vim_strsave(di->di_key);
10745 		    r = filter_map_one(&di->di_tv, expr, map, &rem);
10746 		    clear_tv(&vimvars[VV_KEY].vv_tv);
10747 		    if (r == FAIL || did_emsg)
10748 			break;
10749 		    if (!map && rem)
10750 		    {
10751 			if (var_check_fixed(di->di_flags, arg_errmsg, TRUE)
10752 			    || var_check_ro(di->di_flags, arg_errmsg, TRUE))
10753 			    break;
10754 			dictitem_remove(d, di);
10755 		    }
10756 		}
10757 	    }
10758 	    hash_unlock(ht);
10759 	}
10760 	else if (argvars[0].v_type == VAR_BLOB)
10761 	{
10762 	    int		i;
10763 	    typval_T	tv;
10764 
10765 	    vimvars[VV_KEY].vv_type = VAR_NUMBER;
10766 	    for (i = 0; i < b->bv_ga.ga_len; i++)
10767 	    {
10768 		tv.v_type = VAR_NUMBER;
10769 		tv.vval.v_number = blob_get(b, i);
10770 		vimvars[VV_KEY].vv_nr = idx;
10771 		if (filter_map_one(&tv, expr, map, &rem) == FAIL || did_emsg)
10772 		    break;
10773 		if (tv.v_type != VAR_NUMBER)
10774 		{
10775 		    emsg(_(e_invalblob));
10776 		    return;
10777 		}
10778 		tv.v_type = VAR_NUMBER;
10779 		blob_set(b, i, tv.vval.v_number);
10780 		if (!map && rem)
10781 		{
10782 		    char_u *p = (char_u *)argvars[0].vval.v_blob->bv_ga.ga_data;
10783 
10784 		    mch_memmove(p + idx, p + i + 1,
10785 					      (size_t)b->bv_ga.ga_len - i - 1);
10786 		    --b->bv_ga.ga_len;
10787 		    --i;
10788 		}
10789 	    }
10790 	}
10791 	else
10792 	{
10793 	    // argvars[0].v_type == VAR_LIST
10794 	    vimvars[VV_KEY].vv_type = VAR_NUMBER;
10795 
10796 	    for (li = l->lv_first; li != NULL; li = nli)
10797 	    {
10798 		if (map && tv_check_lock(li->li_tv.v_lock, arg_errmsg, TRUE))
10799 		    break;
10800 		nli = li->li_next;
10801 		vimvars[VV_KEY].vv_nr = idx;
10802 		if (filter_map_one(&li->li_tv, expr, map, &rem) == FAIL
10803 								  || did_emsg)
10804 		    break;
10805 		if (!map && rem)
10806 		    listitem_remove(l, li);
10807 		++idx;
10808 	    }
10809 	}
10810 
10811 	restore_vimvar(VV_KEY, &save_key);
10812 	restore_vimvar(VV_VAL, &save_val);
10813 
10814 	did_emsg |= save_did_emsg;
10815     }
10816 
10817     copy_tv(&argvars[0], rettv);
10818 }
10819 
10820 #endif /* defined(FEAT_MODIFY_FNAME) || defined(FEAT_EVAL) */
10821