xref: /vim-8.2.3635/src/eval.c (revision 723d165c)
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 *prefix, int *first);
249 static void list_one_var_a(char *prefix, char_u *name, int type, char_u *string, int *first);
250 static int tv_check_lock(typval_T *tv, char_u *name, int use_gettext);
251 static char_u *find_option_end(char_u **arg, int *opt_flags);
252 
253 /* for VIM_VERSION_ defines */
254 #include "version.h"
255 
256 /*
257  * Return "n1" divided by "n2", taking care of dividing by zero.
258  */
259 	static varnumber_T
260 num_divide(varnumber_T n1, varnumber_T n2)
261 {
262     varnumber_T	result;
263 
264     if (n2 == 0)	// give an error message?
265     {
266 	if (n1 == 0)
267 	    result = VARNUM_MIN; // similar to NaN
268 	else if (n1 < 0)
269 	    result = -VARNUM_MAX;
270 	else
271 	    result = VARNUM_MAX;
272     }
273     else
274 	result = n1 / n2;
275 
276     return result;
277 }
278 
279 /*
280  * Return "n1" modulus "n2", taking care of dividing by zero.
281  */
282 	static varnumber_T
283 num_modulus(varnumber_T n1, varnumber_T n2)
284 {
285     // Give an error when n2 is 0?
286     return (n2 == 0) ? 0 : (n1 % n2);
287 }
288 
289 
290 #if defined(EBCDIC) || defined(PROTO)
291 /*
292  * Compare struct fst by function name.
293  */
294     static int
295 compare_func_name(const void *s1, const void *s2)
296 {
297     struct fst *p1 = (struct fst *)s1;
298     struct fst *p2 = (struct fst *)s2;
299 
300     return STRCMP(p1->f_name, p2->f_name);
301 }
302 
303 /*
304  * Sort the function table by function name.
305  * The sorting of the table above is ASCII dependent.
306  * On machines using EBCDIC we have to sort it.
307  */
308     static void
309 sortFunctions(void)
310 {
311     int		funcCnt = (int)(sizeof(functions) / sizeof(struct fst)) - 1;
312 
313     qsort(functions, (size_t)funcCnt, sizeof(struct fst), compare_func_name);
314 }
315 #endif
316 
317 
318 /*
319  * Initialize the global and v: variables.
320  */
321     void
322 eval_init(void)
323 {
324     int		    i;
325     struct vimvar   *p;
326 
327     init_var_dict(&globvardict, &globvars_var, VAR_DEF_SCOPE);
328     init_var_dict(&vimvardict, &vimvars_var, VAR_SCOPE);
329     vimvardict.dv_lock = VAR_FIXED;
330     hash_init(&compat_hashtab);
331     func_init();
332 
333     for (i = 0; i < VV_LEN; ++i)
334     {
335 	p = &vimvars[i];
336 	if (STRLEN(p->vv_name) > 16)
337 	{
338 	    iemsg("INTERNAL: name too long, increase size of dictitem16_T");
339 	    getout(1);
340 	}
341 	STRCPY(p->vv_di.di_key, p->vv_name);
342 	if (p->vv_flags & VV_RO)
343 	    p->vv_di.di_flags = DI_FLAGS_RO | DI_FLAGS_FIX;
344 	else if (p->vv_flags & VV_RO_SBX)
345 	    p->vv_di.di_flags = DI_FLAGS_RO_SBX | DI_FLAGS_FIX;
346 	else
347 	    p->vv_di.di_flags = DI_FLAGS_FIX;
348 
349 	/* add to v: scope dict, unless the value is not always available */
350 	if (p->vv_type != VAR_UNKNOWN)
351 	    hash_add(&vimvarht, p->vv_di.di_key);
352 	if (p->vv_flags & VV_COMPAT)
353 	    /* add to compat scope dict */
354 	    hash_add(&compat_hashtab, p->vv_di.di_key);
355     }
356     vimvars[VV_VERSION].vv_nr = VIM_VERSION_100;
357 
358     set_vim_var_nr(VV_SEARCHFORWARD, 1L);
359     set_vim_var_nr(VV_HLSEARCH, 1L);
360     set_vim_var_dict(VV_COMPLETED_ITEM, dict_alloc_lock(VAR_FIXED));
361     set_vim_var_list(VV_ERRORS, list_alloc());
362     set_vim_var_dict(VV_EVENT, dict_alloc_lock(VAR_FIXED));
363 
364     set_vim_var_nr(VV_FALSE, VVAL_FALSE);
365     set_vim_var_nr(VV_TRUE, VVAL_TRUE);
366     set_vim_var_nr(VV_NONE, VVAL_NONE);
367     set_vim_var_nr(VV_NULL, VVAL_NULL);
368 
369     set_vim_var_nr(VV_TYPE_NUMBER,  VAR_TYPE_NUMBER);
370     set_vim_var_nr(VV_TYPE_STRING,  VAR_TYPE_STRING);
371     set_vim_var_nr(VV_TYPE_FUNC,    VAR_TYPE_FUNC);
372     set_vim_var_nr(VV_TYPE_LIST,    VAR_TYPE_LIST);
373     set_vim_var_nr(VV_TYPE_DICT,    VAR_TYPE_DICT);
374     set_vim_var_nr(VV_TYPE_FLOAT,   VAR_TYPE_FLOAT);
375     set_vim_var_nr(VV_TYPE_BOOL,    VAR_TYPE_BOOL);
376     set_vim_var_nr(VV_TYPE_NONE,    VAR_TYPE_NONE);
377     set_vim_var_nr(VV_TYPE_JOB,     VAR_TYPE_JOB);
378     set_vim_var_nr(VV_TYPE_CHANNEL, VAR_TYPE_CHANNEL);
379     set_vim_var_nr(VV_TYPE_BLOB,    VAR_TYPE_BLOB);
380 
381     set_reg_var(0);  /* default for v:register is not 0 but '"' */
382 
383 #ifdef EBCDIC
384     /*
385      * Sort the function table, to enable binary search.
386      */
387     sortFunctions();
388 #endif
389 }
390 
391 #if defined(EXITFREE) || defined(PROTO)
392     void
393 eval_clear(void)
394 {
395     int		    i;
396     struct vimvar   *p;
397 
398     for (i = 0; i < VV_LEN; ++i)
399     {
400 	p = &vimvars[i];
401 	if (p->vv_di.di_tv.v_type == VAR_STRING)
402 	    VIM_CLEAR(p->vv_str);
403 	else if (p->vv_di.di_tv.v_type == VAR_LIST)
404 	{
405 	    list_unref(p->vv_list);
406 	    p->vv_list = NULL;
407 	}
408     }
409     hash_clear(&vimvarht);
410     hash_init(&vimvarht);  /* garbage_collect() will access it */
411     hash_clear(&compat_hashtab);
412 
413     free_scriptnames();
414 # if defined(FEAT_CMDL_COMPL)
415     free_locales();
416 # endif
417 
418     /* global variables */
419     vars_clear(&globvarht);
420 
421     /* autoloaded script names */
422     ga_clear_strings(&ga_loaded);
423 
424     /* Script-local variables. First clear all the variables and in a second
425      * loop free the scriptvar_T, because a variable in one script might hold
426      * a reference to the whole scope of another script. */
427     for (i = 1; i <= ga_scripts.ga_len; ++i)
428 	vars_clear(&SCRIPT_VARS(i));
429     for (i = 1; i <= ga_scripts.ga_len; ++i)
430 	vim_free(SCRIPT_SV(i));
431     ga_clear(&ga_scripts);
432 
433     /* unreferenced lists and dicts */
434     (void)garbage_collect(FALSE);
435 
436     /* functions */
437     free_all_functions();
438 }
439 #endif
440 
441 
442 /*
443  * Set an internal variable to a string value. Creates the variable if it does
444  * not already exist.
445  */
446     void
447 set_internal_string_var(char_u *name, char_u *value)
448 {
449     char_u	*val;
450     typval_T	*tvp;
451 
452     val = vim_strsave(value);
453     if (val != NULL)
454     {
455 	tvp = alloc_string_tv(val);
456 	if (tvp != NULL)
457 	{
458 	    set_var(name, tvp, FALSE);
459 	    free_tv(tvp);
460 	}
461     }
462 }
463 
464 static lval_T	*redir_lval = NULL;
465 #define EVALCMD_BUSY (redir_lval == (lval_T *)&redir_lval)
466 static garray_T redir_ga;	/* only valid when redir_lval is not NULL */
467 static char_u	*redir_endp = NULL;
468 static char_u	*redir_varname = NULL;
469 
470 /*
471  * Start recording command output to a variable
472  * When "append" is TRUE append to an existing variable.
473  * Returns OK if successfully completed the setup.  FAIL otherwise.
474  */
475     int
476 var_redir_start(char_u *name, int append)
477 {
478     int		save_emsg;
479     int		err;
480     typval_T	tv;
481 
482     /* Catch a bad name early. */
483     if (!eval_isnamec1(*name))
484     {
485 	emsg(_(e_invarg));
486 	return FAIL;
487     }
488 
489     /* Make a copy of the name, it is used in redir_lval until redir ends. */
490     redir_varname = vim_strsave(name);
491     if (redir_varname == NULL)
492 	return FAIL;
493 
494     redir_lval = (lval_T *)alloc_clear((unsigned)sizeof(lval_T));
495     if (redir_lval == NULL)
496     {
497 	var_redir_stop();
498 	return FAIL;
499     }
500 
501     /* The output is stored in growarray "redir_ga" until redirection ends. */
502     ga_init2(&redir_ga, (int)sizeof(char), 500);
503 
504     /* Parse the variable name (can be a dict or list entry). */
505     redir_endp = get_lval(redir_varname, NULL, redir_lval, FALSE, FALSE, 0,
506 							     FNE_CHECK_START);
507     if (redir_endp == NULL || redir_lval->ll_name == NULL || *redir_endp != NUL)
508     {
509 	clear_lval(redir_lval);
510 	if (redir_endp != NULL && *redir_endp != NUL)
511 	    /* Trailing characters are present after the variable name */
512 	    emsg(_(e_trailing));
513 	else
514 	    emsg(_(e_invarg));
515 	redir_endp = NULL;  /* don't store a value, only cleanup */
516 	var_redir_stop();
517 	return FAIL;
518     }
519 
520     /* check if we can write to the variable: set it to or append an empty
521      * string */
522     save_emsg = did_emsg;
523     did_emsg = FALSE;
524     tv.v_type = VAR_STRING;
525     tv.vval.v_string = (char_u *)"";
526     if (append)
527 	set_var_lval(redir_lval, redir_endp, &tv, TRUE, (char_u *)".");
528     else
529 	set_var_lval(redir_lval, redir_endp, &tv, TRUE, (char_u *)"=");
530     clear_lval(redir_lval);
531     err = did_emsg;
532     did_emsg |= save_emsg;
533     if (err)
534     {
535 	redir_endp = NULL;  /* don't store a value, only cleanup */
536 	var_redir_stop();
537 	return FAIL;
538     }
539 
540     return OK;
541 }
542 
543 /*
544  * Append "value[value_len]" to the variable set by var_redir_start().
545  * The actual appending is postponed until redirection ends, because the value
546  * appended may in fact be the string we write to, changing it may cause freed
547  * memory to be used:
548  *   :redir => foo
549  *   :let foo
550  *   :redir END
551  */
552     void
553 var_redir_str(char_u *value, int value_len)
554 {
555     int		len;
556 
557     if (redir_lval == NULL)
558 	return;
559 
560     if (value_len == -1)
561 	len = (int)STRLEN(value);	/* Append the entire string */
562     else
563 	len = value_len;		/* Append only "value_len" characters */
564 
565     if (ga_grow(&redir_ga, len) == OK)
566     {
567 	mch_memmove((char *)redir_ga.ga_data + redir_ga.ga_len, value, len);
568 	redir_ga.ga_len += len;
569     }
570     else
571 	var_redir_stop();
572 }
573 
574 /*
575  * Stop redirecting command output to a variable.
576  * Frees the allocated memory.
577  */
578     void
579 var_redir_stop(void)
580 {
581     typval_T	tv;
582 
583     if (EVALCMD_BUSY)
584     {
585 	redir_lval = NULL;
586 	return;
587     }
588 
589     if (redir_lval != NULL)
590     {
591 	/* If there was no error: assign the text to the variable. */
592 	if (redir_endp != NULL)
593 	{
594 	    ga_append(&redir_ga, NUL);  /* Append the trailing NUL. */
595 	    tv.v_type = VAR_STRING;
596 	    tv.vval.v_string = redir_ga.ga_data;
597 	    /* Call get_lval() again, if it's inside a Dict or List it may
598 	     * have changed. */
599 	    redir_endp = get_lval(redir_varname, NULL, redir_lval,
600 					FALSE, FALSE, 0, FNE_CHECK_START);
601 	    if (redir_endp != NULL && redir_lval->ll_name != NULL)
602 		set_var_lval(redir_lval, redir_endp, &tv, FALSE, (char_u *)".");
603 	    clear_lval(redir_lval);
604 	}
605 
606 	/* free the collected output */
607 	VIM_CLEAR(redir_ga.ga_data);
608 
609 	VIM_CLEAR(redir_lval);
610     }
611     VIM_CLEAR(redir_varname);
612 }
613 
614     int
615 eval_charconvert(
616     char_u	*enc_from,
617     char_u	*enc_to,
618     char_u	*fname_from,
619     char_u	*fname_to)
620 {
621     int		err = FALSE;
622 
623     set_vim_var_string(VV_CC_FROM, enc_from, -1);
624     set_vim_var_string(VV_CC_TO, enc_to, -1);
625     set_vim_var_string(VV_FNAME_IN, fname_from, -1);
626     set_vim_var_string(VV_FNAME_OUT, fname_to, -1);
627     if (eval_to_bool(p_ccv, &err, NULL, FALSE))
628 	err = TRUE;
629     set_vim_var_string(VV_CC_FROM, NULL, -1);
630     set_vim_var_string(VV_CC_TO, NULL, -1);
631     set_vim_var_string(VV_FNAME_IN, NULL, -1);
632     set_vim_var_string(VV_FNAME_OUT, NULL, -1);
633 
634     if (err)
635 	return FAIL;
636     return OK;
637 }
638 
639 # if defined(FEAT_POSTSCRIPT) || defined(PROTO)
640     int
641 eval_printexpr(char_u *fname, char_u *args)
642 {
643     int		err = FALSE;
644 
645     set_vim_var_string(VV_FNAME_IN, fname, -1);
646     set_vim_var_string(VV_CMDARG, args, -1);
647     if (eval_to_bool(p_pexpr, &err, NULL, FALSE))
648 	err = TRUE;
649     set_vim_var_string(VV_FNAME_IN, NULL, -1);
650     set_vim_var_string(VV_CMDARG, NULL, -1);
651 
652     if (err)
653     {
654 	mch_remove(fname);
655 	return FAIL;
656     }
657     return OK;
658 }
659 # endif
660 
661 # if defined(FEAT_DIFF) || defined(PROTO)
662     void
663 eval_diff(
664     char_u	*origfile,
665     char_u	*newfile,
666     char_u	*outfile)
667 {
668     int		err = FALSE;
669 
670     set_vim_var_string(VV_FNAME_IN, origfile, -1);
671     set_vim_var_string(VV_FNAME_NEW, newfile, -1);
672     set_vim_var_string(VV_FNAME_OUT, outfile, -1);
673     (void)eval_to_bool(p_dex, &err, NULL, FALSE);
674     set_vim_var_string(VV_FNAME_IN, NULL, -1);
675     set_vim_var_string(VV_FNAME_NEW, NULL, -1);
676     set_vim_var_string(VV_FNAME_OUT, NULL, -1);
677 }
678 
679     void
680 eval_patch(
681     char_u	*origfile,
682     char_u	*difffile,
683     char_u	*outfile)
684 {
685     int		err;
686 
687     set_vim_var_string(VV_FNAME_IN, origfile, -1);
688     set_vim_var_string(VV_FNAME_DIFF, difffile, -1);
689     set_vim_var_string(VV_FNAME_OUT, outfile, -1);
690     (void)eval_to_bool(p_pex, &err, NULL, FALSE);
691     set_vim_var_string(VV_FNAME_IN, NULL, -1);
692     set_vim_var_string(VV_FNAME_DIFF, NULL, -1);
693     set_vim_var_string(VV_FNAME_OUT, NULL, -1);
694 }
695 # endif
696 
697 /*
698  * Top level evaluation function, returning a boolean.
699  * Sets "error" to TRUE if there was an error.
700  * Return TRUE or FALSE.
701  */
702     int
703 eval_to_bool(
704     char_u	*arg,
705     int		*error,
706     char_u	**nextcmd,
707     int		skip)	    /* only parse, don't execute */
708 {
709     typval_T	tv;
710     varnumber_T	retval = FALSE;
711 
712     if (skip)
713 	++emsg_skip;
714     if (eval0(arg, &tv, nextcmd, !skip) == FAIL)
715 	*error = TRUE;
716     else
717     {
718 	*error = FALSE;
719 	if (!skip)
720 	{
721 	    retval = (tv_get_number_chk(&tv, error) != 0);
722 	    clear_tv(&tv);
723 	}
724     }
725     if (skip)
726 	--emsg_skip;
727 
728     return (int)retval;
729 }
730 
731 /*
732  * Call eval1() and give an error message if not done at a lower level.
733  */
734     static int
735 eval1_emsg(char_u **arg, typval_T *rettv, int evaluate)
736 {
737     char_u	*start = *arg;
738     int		ret;
739     int		did_emsg_before = did_emsg;
740     int		called_emsg_before = called_emsg;
741 
742     ret = eval1(arg, rettv, evaluate);
743     if (ret == FAIL)
744     {
745 	// Report the invalid expression unless the expression evaluation has
746 	// been cancelled due to an aborting error, an interrupt, or an
747 	// exception, or we already gave a more specific error.
748 	// Also check called_emsg for when using assert_fails().
749 	if (!aborting() && did_emsg == did_emsg_before
750 					  && called_emsg == called_emsg_before)
751 	    semsg(_(e_invexpr2), start);
752     }
753     return ret;
754 }
755 
756     static int
757 eval_expr_typval(typval_T *expr, typval_T *argv, int argc, typval_T *rettv)
758 {
759     char_u	*s;
760     int		dummy;
761     char_u	buf[NUMBUFLEN];
762 
763     if (expr->v_type == VAR_FUNC)
764     {
765 	s = expr->vval.v_string;
766 	if (s == NULL || *s == NUL)
767 	    return FAIL;
768 	if (call_func(s, (int)STRLEN(s), rettv, argc, argv, NULL,
769 				     0L, 0L, &dummy, TRUE, NULL, NULL) == FAIL)
770 	    return FAIL;
771     }
772     else if (expr->v_type == VAR_PARTIAL)
773     {
774 	partial_T   *partial = expr->vval.v_partial;
775 
776 	s = partial_name(partial);
777 	if (s == NULL || *s == NUL)
778 	    return FAIL;
779 	if (call_func(s, (int)STRLEN(s), rettv, argc, argv, NULL,
780 				  0L, 0L, &dummy, TRUE, partial, NULL) == FAIL)
781 	    return FAIL;
782     }
783     else
784     {
785 	s = tv_get_string_buf_chk(expr, buf);
786 	if (s == NULL)
787 	    return FAIL;
788 	s = skipwhite(s);
789 	if (eval1_emsg(&s, rettv, TRUE) == FAIL)
790 	    return FAIL;
791 	if (*s != NUL)  /* check for trailing chars after expr */
792 	{
793 	    clear_tv(rettv);
794 	    semsg(_(e_invexpr2), s);
795 	    return FAIL;
796 	}
797     }
798     return OK;
799 }
800 
801 /*
802  * Like eval_to_bool() but using a typval_T instead of a string.
803  * Works for string, funcref and partial.
804  */
805     int
806 eval_expr_to_bool(typval_T *expr, int *error)
807 {
808     typval_T	rettv;
809     int		res;
810 
811     if (eval_expr_typval(expr, NULL, 0, &rettv) == FAIL)
812     {
813 	*error = TRUE;
814 	return FALSE;
815     }
816     res = (tv_get_number_chk(&rettv, error) != 0);
817     clear_tv(&rettv);
818     return res;
819 }
820 
821 /*
822  * Top level evaluation function, returning a string.  If "skip" is TRUE,
823  * only parsing to "nextcmd" is done, without reporting errors.  Return
824  * pointer to allocated memory, or NULL for failure or when "skip" is TRUE.
825  */
826     char_u *
827 eval_to_string_skip(
828     char_u	*arg,
829     char_u	**nextcmd,
830     int		skip)	    /* only parse, don't execute */
831 {
832     typval_T	tv;
833     char_u	*retval;
834 
835     if (skip)
836 	++emsg_skip;
837     if (eval0(arg, &tv, nextcmd, !skip) == FAIL || skip)
838 	retval = NULL;
839     else
840     {
841 	retval = vim_strsave(tv_get_string(&tv));
842 	clear_tv(&tv);
843     }
844     if (skip)
845 	--emsg_skip;
846 
847     return retval;
848 }
849 
850 /*
851  * Skip over an expression at "*pp".
852  * Return FAIL for an error, OK otherwise.
853  */
854     int
855 skip_expr(char_u **pp)
856 {
857     typval_T	rettv;
858 
859     *pp = skipwhite(*pp);
860     return eval1(pp, &rettv, FALSE);
861 }
862 
863 /*
864  * Top level evaluation function, returning a string.
865  * When "convert" is TRUE convert a List into a sequence of lines and convert
866  * a Float to a String.
867  * Return pointer to allocated memory, or NULL for failure.
868  */
869     char_u *
870 eval_to_string(
871     char_u	*arg,
872     char_u	**nextcmd,
873     int		convert)
874 {
875     typval_T	tv;
876     char_u	*retval;
877     garray_T	ga;
878 #ifdef FEAT_FLOAT
879     char_u	numbuf[NUMBUFLEN];
880 #endif
881 
882     if (eval0(arg, &tv, nextcmd, TRUE) == FAIL)
883 	retval = NULL;
884     else
885     {
886 	if (convert && tv.v_type == VAR_LIST)
887 	{
888 	    ga_init2(&ga, (int)sizeof(char), 80);
889 	    if (tv.vval.v_list != NULL)
890 	    {
891 		list_join(&ga, tv.vval.v_list, (char_u *)"\n", TRUE, FALSE, 0);
892 		if (tv.vval.v_list->lv_len > 0)
893 		    ga_append(&ga, NL);
894 	    }
895 	    ga_append(&ga, NUL);
896 	    retval = (char_u *)ga.ga_data;
897 	}
898 #ifdef FEAT_FLOAT
899 	else if (convert && tv.v_type == VAR_FLOAT)
900 	{
901 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv.vval.v_float);
902 	    retval = vim_strsave(numbuf);
903 	}
904 #endif
905 	else
906 	    retval = vim_strsave(tv_get_string(&tv));
907 	clear_tv(&tv);
908     }
909 
910     return retval;
911 }
912 
913 /*
914  * Call eval_to_string() without using current local variables and using
915  * textlock.  When "use_sandbox" is TRUE use the sandbox.
916  */
917     char_u *
918 eval_to_string_safe(
919     char_u	*arg,
920     char_u	**nextcmd,
921     int		use_sandbox)
922 {
923     char_u	*retval;
924     funccal_entry_T funccal_entry;
925 
926     save_funccal(&funccal_entry);
927     if (use_sandbox)
928 	++sandbox;
929     ++textlock;
930     retval = eval_to_string(arg, nextcmd, FALSE);
931     if (use_sandbox)
932 	--sandbox;
933     --textlock;
934     restore_funccal();
935     return retval;
936 }
937 
938 /*
939  * Top level evaluation function, returning a number.
940  * Evaluates "expr" silently.
941  * Returns -1 for an error.
942  */
943     varnumber_T
944 eval_to_number(char_u *expr)
945 {
946     typval_T	rettv;
947     varnumber_T	retval;
948     char_u	*p = skipwhite(expr);
949 
950     ++emsg_off;
951 
952     if (eval1(&p, &rettv, TRUE) == FAIL)
953 	retval = -1;
954     else
955     {
956 	retval = tv_get_number_chk(&rettv, NULL);
957 	clear_tv(&rettv);
958     }
959     --emsg_off;
960 
961     return retval;
962 }
963 
964 /*
965  * Prepare v: variable "idx" to be used.
966  * Save the current typeval in "save_tv".
967  * When not used yet add the variable to the v: hashtable.
968  */
969     static void
970 prepare_vimvar(int idx, typval_T *save_tv)
971 {
972     *save_tv = vimvars[idx].vv_tv;
973     if (vimvars[idx].vv_type == VAR_UNKNOWN)
974 	hash_add(&vimvarht, vimvars[idx].vv_di.di_key);
975 }
976 
977 /*
978  * Restore v: variable "idx" to typeval "save_tv".
979  * When no longer defined, remove the variable from the v: hashtable.
980  */
981     static void
982 restore_vimvar(int idx, typval_T *save_tv)
983 {
984     hashitem_T	*hi;
985 
986     vimvars[idx].vv_tv = *save_tv;
987     if (vimvars[idx].vv_type == VAR_UNKNOWN)
988     {
989 	hi = hash_find(&vimvarht, vimvars[idx].vv_di.di_key);
990 	if (HASHITEM_EMPTY(hi))
991 	    internal_error("restore_vimvar()");
992 	else
993 	    hash_remove(&vimvarht, hi);
994     }
995 }
996 
997 #if defined(FEAT_SPELL) || defined(PROTO)
998 /*
999  * Evaluate an expression to a list with suggestions.
1000  * For the "expr:" part of 'spellsuggest'.
1001  * Returns NULL when there is an error.
1002  */
1003     list_T *
1004 eval_spell_expr(char_u *badword, char_u *expr)
1005 {
1006     typval_T	save_val;
1007     typval_T	rettv;
1008     list_T	*list = NULL;
1009     char_u	*p = skipwhite(expr);
1010 
1011     /* Set "v:val" to the bad word. */
1012     prepare_vimvar(VV_VAL, &save_val);
1013     vimvars[VV_VAL].vv_type = VAR_STRING;
1014     vimvars[VV_VAL].vv_str = badword;
1015     if (p_verbose == 0)
1016 	++emsg_off;
1017 
1018     if (eval1(&p, &rettv, TRUE) == OK)
1019     {
1020 	if (rettv.v_type != VAR_LIST)
1021 	    clear_tv(&rettv);
1022 	else
1023 	    list = rettv.vval.v_list;
1024     }
1025 
1026     if (p_verbose == 0)
1027 	--emsg_off;
1028     restore_vimvar(VV_VAL, &save_val);
1029 
1030     return list;
1031 }
1032 
1033 /*
1034  * "list" is supposed to contain two items: a word and a number.  Return the
1035  * word in "pp" and the number as the return value.
1036  * Return -1 if anything isn't right.
1037  * Used to get the good word and score from the eval_spell_expr() result.
1038  */
1039     int
1040 get_spellword(list_T *list, char_u **pp)
1041 {
1042     listitem_T	*li;
1043 
1044     li = list->lv_first;
1045     if (li == NULL)
1046 	return -1;
1047     *pp = tv_get_string(&li->li_tv);
1048 
1049     li = li->li_next;
1050     if (li == NULL)
1051 	return -1;
1052     return (int)tv_get_number(&li->li_tv);
1053 }
1054 #endif
1055 
1056 /*
1057  * Top level evaluation function.
1058  * Returns an allocated typval_T with the result.
1059  * Returns NULL when there is an error.
1060  */
1061     typval_T *
1062 eval_expr(char_u *arg, char_u **nextcmd)
1063 {
1064     typval_T	*tv;
1065 
1066     tv = (typval_T *)alloc(sizeof(typval_T));
1067     if (tv != NULL && eval0(arg, tv, nextcmd, TRUE) == FAIL)
1068 	VIM_CLEAR(tv);
1069 
1070     return tv;
1071 }
1072 
1073 
1074 /*
1075  * Call some Vim script function and return the result in "*rettv".
1076  * Uses argv[0] to argv[argc - 1] for the function arguments.  argv[argc]
1077  * should have type VAR_UNKNOWN.
1078  * Returns OK or FAIL.
1079  */
1080     int
1081 call_vim_function(
1082     char_u      *func,
1083     int		argc,
1084     typval_T	*argv,
1085     typval_T	*rettv)
1086 {
1087     int		doesrange;
1088     int		ret;
1089 
1090     rettv->v_type = VAR_UNKNOWN;		/* clear_tv() uses this */
1091     ret = call_func(func, (int)STRLEN(func), rettv, argc, argv, NULL,
1092 		    curwin->w_cursor.lnum, curwin->w_cursor.lnum,
1093 		    &doesrange, TRUE, NULL, NULL);
1094     if (ret == FAIL)
1095 	clear_tv(rettv);
1096 
1097     return ret;
1098 }
1099 
1100 /*
1101  * Call Vim script function "func" and return the result as a number.
1102  * Returns -1 when calling the function fails.
1103  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
1104  * have type VAR_UNKNOWN.
1105  */
1106     varnumber_T
1107 call_func_retnr(
1108     char_u      *func,
1109     int		argc,
1110     typval_T	*argv)
1111 {
1112     typval_T	rettv;
1113     varnumber_T	retval;
1114 
1115     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
1116 	return -1;
1117 
1118     retval = tv_get_number_chk(&rettv, NULL);
1119     clear_tv(&rettv);
1120     return retval;
1121 }
1122 
1123 #if (defined(FEAT_USR_CMDS) && defined(FEAT_CMDL_COMPL)) \
1124 	|| defined(FEAT_COMPL_FUNC) || defined(PROTO)
1125 
1126 # if (defined(FEAT_USR_CMDS) && defined(FEAT_CMDL_COMPL)) || defined(PROTO)
1127 /*
1128  * Call Vim script function "func" and return the result as a string.
1129  * Returns NULL when calling the function fails.
1130  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
1131  * have type VAR_UNKNOWN.
1132  */
1133     void *
1134 call_func_retstr(
1135     char_u      *func,
1136     int		argc,
1137     typval_T	*argv)
1138 {
1139     typval_T	rettv;
1140     char_u	*retval;
1141 
1142     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
1143 	return NULL;
1144 
1145     retval = vim_strsave(tv_get_string(&rettv));
1146     clear_tv(&rettv);
1147     return retval;
1148 }
1149 # endif
1150 
1151 /*
1152  * Call Vim script function "func" and return the result as a List.
1153  * Uses argv[0] to argv[argc - 1] for the function arguments. argv[argc] should
1154  * have type VAR_UNKNOWN.
1155  * Returns NULL when there is something wrong.
1156  */
1157     void *
1158 call_func_retlist(
1159     char_u      *func,
1160     int		argc,
1161     typval_T	*argv)
1162 {
1163     typval_T	rettv;
1164 
1165     if (call_vim_function(func, argc, argv, &rettv) == FAIL)
1166 	return NULL;
1167 
1168     if (rettv.v_type != VAR_LIST)
1169     {
1170 	clear_tv(&rettv);
1171 	return NULL;
1172     }
1173 
1174     return rettv.vval.v_list;
1175 }
1176 #endif
1177 
1178 
1179 #ifdef FEAT_FOLDING
1180 /*
1181  * Evaluate 'foldexpr'.  Returns the foldlevel, and any character preceding
1182  * it in "*cp".  Doesn't give error messages.
1183  */
1184     int
1185 eval_foldexpr(char_u *arg, int *cp)
1186 {
1187     typval_T	tv;
1188     varnumber_T	retval;
1189     char_u	*s;
1190     int		use_sandbox = was_set_insecurely((char_u *)"foldexpr",
1191 								   OPT_LOCAL);
1192 
1193     ++emsg_off;
1194     if (use_sandbox)
1195 	++sandbox;
1196     ++textlock;
1197     *cp = NUL;
1198     if (eval0(arg, &tv, NULL, TRUE) == FAIL)
1199 	retval = 0;
1200     else
1201     {
1202 	/* If the result is a number, just return the number. */
1203 	if (tv.v_type == VAR_NUMBER)
1204 	    retval = tv.vval.v_number;
1205 	else if (tv.v_type != VAR_STRING || tv.vval.v_string == NULL)
1206 	    retval = 0;
1207 	else
1208 	{
1209 	    /* If the result is a string, check if there is a non-digit before
1210 	     * the number. */
1211 	    s = tv.vval.v_string;
1212 	    if (!VIM_ISDIGIT(*s) && *s != '-')
1213 		*cp = *s++;
1214 	    retval = atol((char *)s);
1215 	}
1216 	clear_tv(&tv);
1217     }
1218     --emsg_off;
1219     if (use_sandbox)
1220 	--sandbox;
1221     --textlock;
1222 
1223     return (int)retval;
1224 }
1225 #endif
1226 
1227 /*
1228  * ":let"			list all variable values
1229  * ":let var1 var2"		list variable values
1230  * ":let var = expr"		assignment command.
1231  * ":let var += expr"		assignment command.
1232  * ":let var -= expr"		assignment command.
1233  * ":let var *= expr"		assignment command.
1234  * ":let var /= expr"		assignment command.
1235  * ":let var %= expr"		assignment command.
1236  * ":let var .= expr"		assignment command.
1237  * ":let [var1, var2] = expr"	unpack list.
1238  */
1239     void
1240 ex_let(exarg_T *eap)
1241 {
1242     char_u	*arg = eap->arg;
1243     char_u	*expr = NULL;
1244     typval_T	rettv;
1245     int		i;
1246     int		var_count = 0;
1247     int		semicolon = 0;
1248     char_u	op[2];
1249     char_u	*argend;
1250     int		first = TRUE;
1251 
1252     argend = skip_var_list(arg, &var_count, &semicolon);
1253     if (argend == NULL)
1254 	return;
1255     if (argend > arg && argend[-1] == '.')  // for var.='str'
1256 	--argend;
1257     expr = skipwhite(argend);
1258     if (*expr != '=' && !(vim_strchr((char_u *)"+-*/%.", *expr) != NULL
1259 			  && expr[1] == '='))
1260     {
1261 	/*
1262 	 * ":let" without "=": list variables
1263 	 */
1264 	if (*arg == '[')
1265 	    emsg(_(e_invarg));
1266 	else if (!ends_excmd(*arg))
1267 	    /* ":let var1 var2" */
1268 	    arg = list_arg_vars(eap, arg, &first);
1269 	else if (!eap->skip)
1270 	{
1271 	    /* ":let" */
1272 	    list_glob_vars(&first);
1273 	    list_buf_vars(&first);
1274 	    list_win_vars(&first);
1275 	    list_tab_vars(&first);
1276 	    list_script_vars(&first);
1277 	    list_func_vars(&first);
1278 	    list_vim_vars(&first);
1279 	}
1280 	eap->nextcmd = check_nextcmd(arg);
1281     }
1282     else
1283     {
1284 	op[0] = '=';
1285 	op[1] = NUL;
1286 	if (*expr != '=')
1287 	{
1288 	    if (vim_strchr((char_u *)"+-*/%.", *expr) != NULL)
1289 		op[0] = *expr;   // +=, -=, *=, /=, %= or .=
1290 	    expr = skipwhite(expr + 2);
1291 	}
1292 	else
1293 	    expr = skipwhite(expr + 1);
1294 
1295 	if (eap->skip)
1296 	    ++emsg_skip;
1297 	i = eval0(expr, &rettv, &eap->nextcmd, !eap->skip);
1298 	if (eap->skip)
1299 	{
1300 	    if (i != FAIL)
1301 		clear_tv(&rettv);
1302 	    --emsg_skip;
1303 	}
1304 	else if (i != FAIL)
1305 	{
1306 	    (void)ex_let_vars(eap->arg, &rettv, FALSE, semicolon, var_count,
1307 									  op);
1308 	    clear_tv(&rettv);
1309 	}
1310     }
1311 }
1312 
1313 /*
1314  * Assign the typevalue "tv" to the variable or variables at "arg_start".
1315  * Handles both "var" with any type and "[var, var; var]" with a list type.
1316  * When "nextchars" is not NULL it points to a string with characters that
1317  * must appear after the variable(s).  Use "+", "-" or "." for add, subtract
1318  * or concatenate.
1319  * Returns OK or FAIL;
1320  */
1321     static int
1322 ex_let_vars(
1323     char_u	*arg_start,
1324     typval_T	*tv,
1325     int		copy,		/* copy values from "tv", don't move */
1326     int		semicolon,	/* from skip_var_list() */
1327     int		var_count,	/* from skip_var_list() */
1328     char_u	*nextchars)
1329 {
1330     char_u	*arg = arg_start;
1331     list_T	*l;
1332     int		i;
1333     listitem_T	*item;
1334     typval_T	ltv;
1335 
1336     if (*arg != '[')
1337     {
1338 	/*
1339 	 * ":let var = expr" or ":for var in list"
1340 	 */
1341 	if (ex_let_one(arg, tv, copy, nextchars, nextchars) == NULL)
1342 	    return FAIL;
1343 	return OK;
1344     }
1345 
1346     /*
1347      * ":let [v1, v2] = list" or ":for [v1, v2] in listlist"
1348      */
1349     if (tv->v_type != VAR_LIST || (l = tv->vval.v_list) == NULL)
1350     {
1351 	emsg(_(e_listreq));
1352 	return FAIL;
1353     }
1354 
1355     i = list_len(l);
1356     if (semicolon == 0 && var_count < i)
1357     {
1358 	emsg(_("E687: Less targets than List items"));
1359 	return FAIL;
1360     }
1361     if (var_count - semicolon > i)
1362     {
1363 	emsg(_("E688: More targets than List items"));
1364 	return FAIL;
1365     }
1366 
1367     item = l->lv_first;
1368     while (*arg != ']')
1369     {
1370 	arg = skipwhite(arg + 1);
1371 	arg = ex_let_one(arg, &item->li_tv, TRUE, (char_u *)",;]", nextchars);
1372 	item = item->li_next;
1373 	if (arg == NULL)
1374 	    return FAIL;
1375 
1376 	arg = skipwhite(arg);
1377 	if (*arg == ';')
1378 	{
1379 	    /* Put the rest of the list (may be empty) in the var after ';'.
1380 	     * Create a new list for this. */
1381 	    l = list_alloc();
1382 	    if (l == NULL)
1383 		return FAIL;
1384 	    while (item != NULL)
1385 	    {
1386 		list_append_tv(l, &item->li_tv);
1387 		item = item->li_next;
1388 	    }
1389 
1390 	    ltv.v_type = VAR_LIST;
1391 	    ltv.v_lock = 0;
1392 	    ltv.vval.v_list = l;
1393 	    l->lv_refcount = 1;
1394 
1395 	    arg = ex_let_one(skipwhite(arg + 1), &ltv, FALSE,
1396 						    (char_u *)"]", nextchars);
1397 	    clear_tv(&ltv);
1398 	    if (arg == NULL)
1399 		return FAIL;
1400 	    break;
1401 	}
1402 	else if (*arg != ',' && *arg != ']')
1403 	{
1404 	    internal_error("ex_let_vars()");
1405 	    return FAIL;
1406 	}
1407     }
1408 
1409     return OK;
1410 }
1411 
1412 /*
1413  * Skip over assignable variable "var" or list of variables "[var, var]".
1414  * Used for ":let varvar = expr" and ":for varvar in expr".
1415  * For "[var, var]" increment "*var_count" for each variable.
1416  * for "[var, var; var]" set "semicolon".
1417  * Return NULL for an error.
1418  */
1419     static char_u *
1420 skip_var_list(
1421     char_u	*arg,
1422     int		*var_count,
1423     int		*semicolon)
1424 {
1425     char_u	*p, *s;
1426 
1427     if (*arg == '[')
1428     {
1429 	/* "[var, var]": find the matching ']'. */
1430 	p = arg;
1431 	for (;;)
1432 	{
1433 	    p = skipwhite(p + 1);	/* skip whites after '[', ';' or ',' */
1434 	    s = skip_var_one(p);
1435 	    if (s == p)
1436 	    {
1437 		semsg(_(e_invarg2), p);
1438 		return NULL;
1439 	    }
1440 	    ++*var_count;
1441 
1442 	    p = skipwhite(s);
1443 	    if (*p == ']')
1444 		break;
1445 	    else if (*p == ';')
1446 	    {
1447 		if (*semicolon == 1)
1448 		{
1449 		    emsg(_("Double ; in list of variables"));
1450 		    return NULL;
1451 		}
1452 		*semicolon = 1;
1453 	    }
1454 	    else if (*p != ',')
1455 	    {
1456 		semsg(_(e_invarg2), p);
1457 		return NULL;
1458 	    }
1459 	}
1460 	return p + 1;
1461     }
1462     else
1463 	return skip_var_one(arg);
1464 }
1465 
1466 /*
1467  * Skip one (assignable) variable name, including @r, $VAR, &option, d.key,
1468  * l[idx].
1469  */
1470     static char_u *
1471 skip_var_one(char_u *arg)
1472 {
1473     if (*arg == '@' && arg[1] != NUL)
1474 	return arg + 2;
1475     return find_name_end(*arg == '$' || *arg == '&' ? arg + 1 : arg,
1476 				   NULL, NULL, FNE_INCL_BR | FNE_CHECK_START);
1477 }
1478 
1479 /*
1480  * List variables for hashtab "ht" with prefix "prefix".
1481  * If "empty" is TRUE also list NULL strings as empty strings.
1482  */
1483     void
1484 list_hashtable_vars(
1485     hashtab_T	*ht,
1486     char	*prefix,
1487     int		empty,
1488     int		*first)
1489 {
1490     hashitem_T	*hi;
1491     dictitem_T	*di;
1492     int		todo;
1493     char_u	buf[IOSIZE];
1494 
1495     todo = (int)ht->ht_used;
1496     for (hi = ht->ht_array; todo > 0 && !got_int; ++hi)
1497     {
1498 	if (!HASHITEM_EMPTY(hi))
1499 	{
1500 	    --todo;
1501 	    di = HI2DI(hi);
1502 
1503 	    // apply :filter /pat/ to variable name
1504 	    vim_strncpy((char_u *)buf, (char_u *)prefix, IOSIZE - 1);
1505 	    vim_strcat((char_u *)buf, di->di_key, IOSIZE);
1506 	    if (message_filtered(buf))
1507 		continue;
1508 
1509 	    if (empty || di->di_tv.v_type != VAR_STRING
1510 					   || di->di_tv.vval.v_string != NULL)
1511 		list_one_var(di, prefix, first);
1512 	}
1513     }
1514 }
1515 
1516 /*
1517  * List global variables.
1518  */
1519     static void
1520 list_glob_vars(int *first)
1521 {
1522     list_hashtable_vars(&globvarht, "", TRUE, first);
1523 }
1524 
1525 /*
1526  * List buffer variables.
1527  */
1528     static void
1529 list_buf_vars(int *first)
1530 {
1531     list_hashtable_vars(&curbuf->b_vars->dv_hashtab, "b:", TRUE, first);
1532 }
1533 
1534 /*
1535  * List window variables.
1536  */
1537     static void
1538 list_win_vars(int *first)
1539 {
1540     list_hashtable_vars(&curwin->w_vars->dv_hashtab, "w:", TRUE, first);
1541 }
1542 
1543 /*
1544  * List tab page variables.
1545  */
1546     static void
1547 list_tab_vars(int *first)
1548 {
1549     list_hashtable_vars(&curtab->tp_vars->dv_hashtab, "t:", TRUE, first);
1550 }
1551 
1552 /*
1553  * List Vim variables.
1554  */
1555     static void
1556 list_vim_vars(int *first)
1557 {
1558     list_hashtable_vars(&vimvarht, "v:", FALSE, first);
1559 }
1560 
1561 /*
1562  * List script-local variables, if there is a script.
1563  */
1564     static void
1565 list_script_vars(int *first)
1566 {
1567     if (current_sctx.sc_sid > 0 && current_sctx.sc_sid <= ga_scripts.ga_len)
1568 	list_hashtable_vars(&SCRIPT_VARS(current_sctx.sc_sid),
1569 							   "s:", FALSE, first);
1570 }
1571 
1572 /*
1573  * List variables in "arg".
1574  */
1575     static char_u *
1576 list_arg_vars(exarg_T *eap, char_u *arg, int *first)
1577 {
1578     int		error = FALSE;
1579     int		len;
1580     char_u	*name;
1581     char_u	*name_start;
1582     char_u	*arg_subsc;
1583     char_u	*tofree;
1584     typval_T    tv;
1585 
1586     while (!ends_excmd(*arg) && !got_int)
1587     {
1588 	if (error || eap->skip)
1589 	{
1590 	    arg = find_name_end(arg, NULL, NULL, FNE_INCL_BR | FNE_CHECK_START);
1591 	    if (!VIM_ISWHITE(*arg) && !ends_excmd(*arg))
1592 	    {
1593 		emsg_severe = TRUE;
1594 		emsg(_(e_trailing));
1595 		break;
1596 	    }
1597 	}
1598 	else
1599 	{
1600 	    /* get_name_len() takes care of expanding curly braces */
1601 	    name_start = name = arg;
1602 	    len = get_name_len(&arg, &tofree, TRUE, TRUE);
1603 	    if (len <= 0)
1604 	    {
1605 		/* This is mainly to keep test 49 working: when expanding
1606 		 * curly braces fails overrule the exception error message. */
1607 		if (len < 0 && !aborting())
1608 		{
1609 		    emsg_severe = TRUE;
1610 		    semsg(_(e_invarg2), arg);
1611 		    break;
1612 		}
1613 		error = TRUE;
1614 	    }
1615 	    else
1616 	    {
1617 		if (tofree != NULL)
1618 		    name = tofree;
1619 		if (get_var_tv(name, len, &tv, NULL, TRUE, FALSE) == FAIL)
1620 		    error = TRUE;
1621 		else
1622 		{
1623 		    /* handle d.key, l[idx], f(expr) */
1624 		    arg_subsc = arg;
1625 		    if (handle_subscript(&arg, &tv, TRUE, TRUE) == FAIL)
1626 			error = TRUE;
1627 		    else
1628 		    {
1629 			if (arg == arg_subsc && len == 2 && name[1] == ':')
1630 			{
1631 			    switch (*name)
1632 			    {
1633 				case 'g': list_glob_vars(first); break;
1634 				case 'b': list_buf_vars(first); break;
1635 				case 'w': list_win_vars(first); break;
1636 				case 't': list_tab_vars(first); break;
1637 				case 'v': list_vim_vars(first); break;
1638 				case 's': list_script_vars(first); break;
1639 				case 'l': list_func_vars(first); break;
1640 				default:
1641 					  semsg(_("E738: Can't list variables for %s"), name);
1642 			    }
1643 			}
1644 			else
1645 			{
1646 			    char_u	numbuf[NUMBUFLEN];
1647 			    char_u	*tf;
1648 			    int		c;
1649 			    char_u	*s;
1650 
1651 			    s = echo_string(&tv, &tf, numbuf, 0);
1652 			    c = *arg;
1653 			    *arg = NUL;
1654 			    list_one_var_a("",
1655 				    arg == arg_subsc ? name : name_start,
1656 				    tv.v_type,
1657 				    s == NULL ? (char_u *)"" : s,
1658 				    first);
1659 			    *arg = c;
1660 			    vim_free(tf);
1661 			}
1662 			clear_tv(&tv);
1663 		    }
1664 		}
1665 	    }
1666 
1667 	    vim_free(tofree);
1668 	}
1669 
1670 	arg = skipwhite(arg);
1671     }
1672 
1673     return arg;
1674 }
1675 
1676 /*
1677  * Set one item of ":let var = expr" or ":let [v1, v2] = list" to its value.
1678  * Returns a pointer to the char just after the var name.
1679  * Returns NULL if there is an error.
1680  */
1681     static char_u *
1682 ex_let_one(
1683     char_u	*arg,		/* points to variable name */
1684     typval_T	*tv,		/* value to assign to variable */
1685     int		copy,		/* copy value from "tv" */
1686     char_u	*endchars,	/* valid chars after variable name  or NULL */
1687     char_u	*op)		/* "+", "-", "."  or NULL*/
1688 {
1689     int		c1;
1690     char_u	*name;
1691     char_u	*p;
1692     char_u	*arg_end = NULL;
1693     int		len;
1694     int		opt_flags;
1695     char_u	*tofree = NULL;
1696 
1697     /*
1698      * ":let $VAR = expr": Set environment variable.
1699      */
1700     if (*arg == '$')
1701     {
1702 	/* Find the end of the name. */
1703 	++arg;
1704 	name = arg;
1705 	len = get_env_len(&arg);
1706 	if (len == 0)
1707 	    semsg(_(e_invarg2), name - 1);
1708 	else
1709 	{
1710 	    if (op != NULL && vim_strchr((char_u *)"+-*/%", *op) != NULL)
1711 		semsg(_(e_letwrong), op);
1712 	    else if (endchars != NULL
1713 			     && vim_strchr(endchars, *skipwhite(arg)) == NULL)
1714 		emsg(_(e_letunexp));
1715 	    else if (!check_secure())
1716 	    {
1717 		c1 = name[len];
1718 		name[len] = NUL;
1719 		p = tv_get_string_chk(tv);
1720 		if (p != NULL && op != NULL && *op == '.')
1721 		{
1722 		    int	    mustfree = FALSE;
1723 		    char_u  *s = vim_getenv(name, &mustfree);
1724 
1725 		    if (s != NULL)
1726 		    {
1727 			p = tofree = concat_str(s, p);
1728 			if (mustfree)
1729 			    vim_free(s);
1730 		    }
1731 		}
1732 		if (p != NULL)
1733 		{
1734 		    vim_setenv(name, p);
1735 		    if (STRICMP(name, "HOME") == 0)
1736 			init_homedir();
1737 		    else if (didset_vim && STRICMP(name, "VIM") == 0)
1738 			didset_vim = FALSE;
1739 		    else if (didset_vimruntime
1740 					&& STRICMP(name, "VIMRUNTIME") == 0)
1741 			didset_vimruntime = FALSE;
1742 		    arg_end = arg;
1743 		}
1744 		name[len] = c1;
1745 		vim_free(tofree);
1746 	    }
1747 	}
1748     }
1749 
1750     /*
1751      * ":let &option = expr": Set option value.
1752      * ":let &l:option = expr": Set local option value.
1753      * ":let &g:option = expr": Set global option value.
1754      */
1755     else if (*arg == '&')
1756     {
1757 	/* Find the end of the name. */
1758 	p = find_option_end(&arg, &opt_flags);
1759 	if (p == NULL || (endchars != NULL
1760 			      && vim_strchr(endchars, *skipwhite(p)) == NULL))
1761 	    emsg(_(e_letunexp));
1762 	else
1763 	{
1764 	    long	n;
1765 	    int		opt_type;
1766 	    long	numval;
1767 	    char_u	*stringval = NULL;
1768 	    char_u	*s;
1769 
1770 	    c1 = *p;
1771 	    *p = NUL;
1772 
1773 	    n = (long)tv_get_number(tv);
1774 	    s = tv_get_string_chk(tv);	    /* != NULL if number or string */
1775 	    if (s != NULL && op != NULL && *op != '=')
1776 	    {
1777 		opt_type = get_option_value(arg, &numval,
1778 						       &stringval, opt_flags);
1779 		if ((opt_type == 1 && *op == '.')
1780 			|| (opt_type == 0 && *op != '.'))
1781 		{
1782 		    semsg(_(e_letwrong), op);
1783 		    s = NULL;  // don't set the value
1784 		}
1785 		else
1786 		{
1787 		    if (opt_type == 1)  // number
1788 		    {
1789 			switch (*op)
1790 			{
1791 			    case '+': n = numval + n; break;
1792 			    case '-': n = numval - n; break;
1793 			    case '*': n = numval * n; break;
1794 			    case '/': n = (long)num_divide(numval, n); break;
1795 			    case '%': n = (long)num_modulus(numval, n); break;
1796 			}
1797 		    }
1798 		    else if (opt_type == 0 && stringval != NULL) // string
1799 		    {
1800 			s = concat_str(stringval, s);
1801 			vim_free(stringval);
1802 			stringval = s;
1803 		    }
1804 		}
1805 	    }
1806 	    if (s != NULL)
1807 	    {
1808 		set_option_value(arg, n, s, opt_flags);
1809 		arg_end = p;
1810 	    }
1811 	    *p = c1;
1812 	    vim_free(stringval);
1813 	}
1814     }
1815 
1816     /*
1817      * ":let @r = expr": Set register contents.
1818      */
1819     else if (*arg == '@')
1820     {
1821 	++arg;
1822 	if (op != NULL && vim_strchr((char_u *)"+-*/%", *op) != NULL)
1823 	    semsg(_(e_letwrong), op);
1824 	else if (endchars != NULL
1825 			 && vim_strchr(endchars, *skipwhite(arg + 1)) == NULL)
1826 	    emsg(_(e_letunexp));
1827 	else
1828 	{
1829 	    char_u	*ptofree = NULL;
1830 	    char_u	*s;
1831 
1832 	    p = tv_get_string_chk(tv);
1833 	    if (p != NULL && op != NULL && *op == '.')
1834 	    {
1835 		s = get_reg_contents(*arg == '@' ? '"' : *arg, GREG_EXPR_SRC);
1836 		if (s != NULL)
1837 		{
1838 		    p = ptofree = concat_str(s, p);
1839 		    vim_free(s);
1840 		}
1841 	    }
1842 	    if (p != NULL)
1843 	    {
1844 		write_reg_contents(*arg == '@' ? '"' : *arg, p, -1, FALSE);
1845 		arg_end = arg + 1;
1846 	    }
1847 	    vim_free(ptofree);
1848 	}
1849     }
1850 
1851     /*
1852      * ":let var = expr": Set internal variable.
1853      * ":let {expr} = expr": Idem, name made with curly braces
1854      */
1855     else if (eval_isnamec1(*arg) || *arg == '{')
1856     {
1857 	lval_T	lv;
1858 
1859 	p = get_lval(arg, tv, &lv, FALSE, FALSE, 0, FNE_CHECK_START);
1860 	if (p != NULL && lv.ll_name != NULL)
1861 	{
1862 	    if (endchars != NULL && vim_strchr(endchars, *skipwhite(p)) == NULL)
1863 		emsg(_(e_letunexp));
1864 	    else
1865 	    {
1866 		set_var_lval(&lv, p, tv, copy, op);
1867 		arg_end = p;
1868 	    }
1869 	}
1870 	clear_lval(&lv);
1871     }
1872 
1873     else
1874 	semsg(_(e_invarg2), arg);
1875 
1876     return arg_end;
1877 }
1878 
1879 /*
1880  * Get an lval: variable, Dict item or List item that can be assigned a value
1881  * to: "name", "na{me}", "name[expr]", "name[expr:expr]", "name[expr][expr]",
1882  * "name.key", "name.key[expr]" etc.
1883  * Indexing only works if "name" is an existing List or Dictionary.
1884  * "name" points to the start of the name.
1885  * If "rettv" is not NULL it points to the value to be assigned.
1886  * "unlet" is TRUE for ":unlet": slightly different behavior when something is
1887  * wrong; must end in space or cmd separator.
1888  *
1889  * flags:
1890  *  GLV_QUIET:       do not give error messages
1891  *  GLV_READ_ONLY:   will not change the variable
1892  *  GLV_NO_AUTOLOAD: do not use script autoloading
1893  *
1894  * Returns a pointer to just after the name, including indexes.
1895  * When an evaluation error occurs "lp->ll_name" is NULL;
1896  * Returns NULL for a parsing error.  Still need to free items in "lp"!
1897  */
1898     char_u *
1899 get_lval(
1900     char_u	*name,
1901     typval_T	*rettv,
1902     lval_T	*lp,
1903     int		unlet,
1904     int		skip,
1905     int		flags,	    /* GLV_ values */
1906     int		fne_flags)  /* flags for find_name_end() */
1907 {
1908     char_u	*p;
1909     char_u	*expr_start, *expr_end;
1910     int		cc;
1911     dictitem_T	*v;
1912     typval_T	var1;
1913     typval_T	var2;
1914     int		empty1 = FALSE;
1915     listitem_T	*ni;
1916     char_u	*key = NULL;
1917     int		len;
1918     hashtab_T	*ht;
1919     int		quiet = flags & GLV_QUIET;
1920 
1921     /* Clear everything in "lp". */
1922     vim_memset(lp, 0, sizeof(lval_T));
1923 
1924     if (skip)
1925     {
1926 	/* When skipping just find the end of the name. */
1927 	lp->ll_name = name;
1928 	return find_name_end(name, NULL, NULL, FNE_INCL_BR | fne_flags);
1929     }
1930 
1931     /* Find the end of the name. */
1932     p = find_name_end(name, &expr_start, &expr_end, fne_flags);
1933     if (expr_start != NULL)
1934     {
1935 	/* Don't expand the name when we already know there is an error. */
1936 	if (unlet && !VIM_ISWHITE(*p) && !ends_excmd(*p)
1937 						    && *p != '[' && *p != '.')
1938 	{
1939 	    emsg(_(e_trailing));
1940 	    return NULL;
1941 	}
1942 
1943 	lp->ll_exp_name = make_expanded_name(name, expr_start, expr_end, p);
1944 	if (lp->ll_exp_name == NULL)
1945 	{
1946 	    /* Report an invalid expression in braces, unless the
1947 	     * expression evaluation has been cancelled due to an
1948 	     * aborting error, an interrupt, or an exception. */
1949 	    if (!aborting() && !quiet)
1950 	    {
1951 		emsg_severe = TRUE;
1952 		semsg(_(e_invarg2), name);
1953 		return NULL;
1954 	    }
1955 	}
1956 	lp->ll_name = lp->ll_exp_name;
1957     }
1958     else
1959 	lp->ll_name = name;
1960 
1961     /* Without [idx] or .key we are done. */
1962     if ((*p != '[' && *p != '.') || lp->ll_name == NULL)
1963 	return p;
1964 
1965     cc = *p;
1966     *p = NUL;
1967     /* Only pass &ht when we would write to the variable, it prevents autoload
1968      * as well. */
1969     v = find_var(lp->ll_name, (flags & GLV_READ_ONLY) ? NULL : &ht,
1970 						      flags & GLV_NO_AUTOLOAD);
1971     if (v == NULL && !quiet)
1972 	semsg(_(e_undefvar), lp->ll_name);
1973     *p = cc;
1974     if (v == NULL)
1975 	return NULL;
1976 
1977     /*
1978      * Loop until no more [idx] or .key is following.
1979      */
1980     lp->ll_tv = &v->di_tv;
1981     var1.v_type = VAR_UNKNOWN;
1982     var2.v_type = VAR_UNKNOWN;
1983     while (*p == '[' || (*p == '.' && lp->ll_tv->v_type == VAR_DICT))
1984     {
1985 	if (!(lp->ll_tv->v_type == VAR_LIST && lp->ll_tv->vval.v_list != NULL)
1986 		&& !(lp->ll_tv->v_type == VAR_DICT
1987 					   && lp->ll_tv->vval.v_dict != NULL)
1988 		&& !(lp->ll_tv->v_type == VAR_BLOB
1989 					   && lp->ll_tv->vval.v_blob != NULL))
1990 	{
1991 	    if (!quiet)
1992 		emsg(_("E689: Can only index a List, Dictionary or Blob"));
1993 	    return NULL;
1994 	}
1995 	if (lp->ll_range)
1996 	{
1997 	    if (!quiet)
1998 		emsg(_("E708: [:] must come last"));
1999 	    return NULL;
2000 	}
2001 
2002 	len = -1;
2003 	if (*p == '.')
2004 	{
2005 	    key = p + 1;
2006 	    for (len = 0; ASCII_ISALNUM(key[len]) || key[len] == '_'; ++len)
2007 		;
2008 	    if (len == 0)
2009 	    {
2010 		if (!quiet)
2011 		    emsg(_(e_emptykey));
2012 		return NULL;
2013 	    }
2014 	    p = key + len;
2015 	}
2016 	else
2017 	{
2018 	    /* Get the index [expr] or the first index [expr: ]. */
2019 	    p = skipwhite(p + 1);
2020 	    if (*p == ':')
2021 		empty1 = TRUE;
2022 	    else
2023 	    {
2024 		empty1 = FALSE;
2025 		if (eval1(&p, &var1, TRUE) == FAIL)	/* recursive! */
2026 		    return NULL;
2027 		if (tv_get_string_chk(&var1) == NULL)
2028 		{
2029 		    /* not a number or string */
2030 		    clear_tv(&var1);
2031 		    return NULL;
2032 		}
2033 	    }
2034 
2035 	    /* Optionally get the second index [ :expr]. */
2036 	    if (*p == ':')
2037 	    {
2038 		if (lp->ll_tv->v_type == VAR_DICT)
2039 		{
2040 		    if (!quiet)
2041 			emsg(_(e_dictrange));
2042 		    clear_tv(&var1);
2043 		    return NULL;
2044 		}
2045 		if (rettv != NULL
2046 			&& !(rettv->v_type == VAR_LIST
2047 						 && rettv->vval.v_list != NULL)
2048 			&& !(rettv->v_type == VAR_BLOB
2049 						&& rettv->vval.v_blob != NULL))
2050 		{
2051 		    if (!quiet)
2052 			emsg(_("E709: [:] requires a List or Blob value"));
2053 		    clear_tv(&var1);
2054 		    return NULL;
2055 		}
2056 		p = skipwhite(p + 1);
2057 		if (*p == ']')
2058 		    lp->ll_empty2 = TRUE;
2059 		else
2060 		{
2061 		    lp->ll_empty2 = FALSE;
2062 		    if (eval1(&p, &var2, TRUE) == FAIL)	/* recursive! */
2063 		    {
2064 			clear_tv(&var1);
2065 			return NULL;
2066 		    }
2067 		    if (tv_get_string_chk(&var2) == NULL)
2068 		    {
2069 			/* not a number or string */
2070 			clear_tv(&var1);
2071 			clear_tv(&var2);
2072 			return NULL;
2073 		    }
2074 		}
2075 		lp->ll_range = TRUE;
2076 	    }
2077 	    else
2078 		lp->ll_range = FALSE;
2079 
2080 	    if (*p != ']')
2081 	    {
2082 		if (!quiet)
2083 		    emsg(_(e_missbrac));
2084 		clear_tv(&var1);
2085 		clear_tv(&var2);
2086 		return NULL;
2087 	    }
2088 
2089 	    /* Skip to past ']'. */
2090 	    ++p;
2091 	}
2092 
2093 	if (lp->ll_tv->v_type == VAR_DICT)
2094 	{
2095 	    if (len == -1)
2096 	    {
2097 		/* "[key]": get key from "var1" */
2098 		key = tv_get_string_chk(&var1);	/* is number or string */
2099 		if (key == NULL)
2100 		{
2101 		    clear_tv(&var1);
2102 		    return NULL;
2103 		}
2104 	    }
2105 	    lp->ll_list = NULL;
2106 	    lp->ll_dict = lp->ll_tv->vval.v_dict;
2107 	    lp->ll_di = dict_find(lp->ll_dict, key, len);
2108 
2109 	    /* When assigning to a scope dictionary check that a function and
2110 	     * variable name is valid (only variable name unless it is l: or
2111 	     * g: dictionary). Disallow overwriting a builtin function. */
2112 	    if (rettv != NULL && lp->ll_dict->dv_scope != 0)
2113 	    {
2114 		int prevval;
2115 		int wrong;
2116 
2117 		if (len != -1)
2118 		{
2119 		    prevval = key[len];
2120 		    key[len] = NUL;
2121 		}
2122 		else
2123 		    prevval = 0; /* avoid compiler warning */
2124 		wrong = (lp->ll_dict->dv_scope == VAR_DEF_SCOPE
2125 			       && rettv->v_type == VAR_FUNC
2126 			       && var_check_func_name(key, lp->ll_di == NULL))
2127 			|| !valid_varname(key);
2128 		if (len != -1)
2129 		    key[len] = prevval;
2130 		if (wrong)
2131 		    return NULL;
2132 	    }
2133 
2134 	    if (lp->ll_di == NULL)
2135 	    {
2136 		// Can't add "v:" or "a:" variable.
2137 		if (lp->ll_dict == &vimvardict
2138 			 || &lp->ll_dict->dv_hashtab == get_funccal_args_ht())
2139 		{
2140 		    semsg(_(e_illvar), name);
2141 		    clear_tv(&var1);
2142 		    return NULL;
2143 		}
2144 
2145 		// Key does not exist in dict: may need to add it.
2146 		if (*p == '[' || *p == '.' || unlet)
2147 		{
2148 		    if (!quiet)
2149 			semsg(_(e_dictkey), key);
2150 		    clear_tv(&var1);
2151 		    return NULL;
2152 		}
2153 		if (len == -1)
2154 		    lp->ll_newkey = vim_strsave(key);
2155 		else
2156 		    lp->ll_newkey = vim_strnsave(key, len);
2157 		clear_tv(&var1);
2158 		if (lp->ll_newkey == NULL)
2159 		    p = NULL;
2160 		break;
2161 	    }
2162 	    /* existing variable, need to check if it can be changed */
2163 	    else if ((flags & GLV_READ_ONLY) == 0
2164 			     && var_check_ro(lp->ll_di->di_flags, name, FALSE))
2165 	    {
2166 		clear_tv(&var1);
2167 		return NULL;
2168 	    }
2169 
2170 	    clear_tv(&var1);
2171 	    lp->ll_tv = &lp->ll_di->di_tv;
2172 	}
2173 	else if (lp->ll_tv->v_type == VAR_BLOB)
2174 	{
2175 	    long bloblen = blob_len(lp->ll_tv->vval.v_blob);
2176 
2177 	    /*
2178 	     * Get the number and item for the only or first index of the List.
2179 	     */
2180 	    if (empty1)
2181 		lp->ll_n1 = 0;
2182 	    else
2183 		// is number or string
2184 		lp->ll_n1 = (long)tv_get_number(&var1);
2185 	    clear_tv(&var1);
2186 
2187 	    if (lp->ll_n1 < 0
2188 		    || lp->ll_n1 > bloblen
2189 		    || (lp->ll_range && lp->ll_n1 == bloblen))
2190 	    {
2191 		if (!quiet)
2192 		    semsg(_(e_blobidx), lp->ll_n1);
2193 		clear_tv(&var2);
2194 		return NULL;
2195 	    }
2196 	    if (lp->ll_range && !lp->ll_empty2)
2197 	    {
2198 		lp->ll_n2 = (long)tv_get_number(&var2);
2199 		clear_tv(&var2);
2200 		if (lp->ll_n2 < 0
2201 			|| lp->ll_n2 >= bloblen
2202 			|| lp->ll_n2 < lp->ll_n1)
2203 		{
2204 		    if (!quiet)
2205 			semsg(_(e_blobidx), lp->ll_n2);
2206 		    return NULL;
2207 		}
2208 	    }
2209 	    lp->ll_blob = lp->ll_tv->vval.v_blob;
2210 	    lp->ll_tv = NULL;
2211 	    break;
2212 	}
2213 	else
2214 	{
2215 	    /*
2216 	     * Get the number and item for the only or first index of the List.
2217 	     */
2218 	    if (empty1)
2219 		lp->ll_n1 = 0;
2220 	    else
2221 		/* is number or string */
2222 		lp->ll_n1 = (long)tv_get_number(&var1);
2223 	    clear_tv(&var1);
2224 
2225 	    lp->ll_dict = NULL;
2226 	    lp->ll_list = lp->ll_tv->vval.v_list;
2227 	    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
2228 	    if (lp->ll_li == NULL)
2229 	    {
2230 		if (lp->ll_n1 < 0)
2231 		{
2232 		    lp->ll_n1 = 0;
2233 		    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
2234 		}
2235 	    }
2236 	    if (lp->ll_li == NULL)
2237 	    {
2238 		clear_tv(&var2);
2239 		if (!quiet)
2240 		    semsg(_(e_listidx), lp->ll_n1);
2241 		return NULL;
2242 	    }
2243 
2244 	    /*
2245 	     * May need to find the item or absolute index for the second
2246 	     * index of a range.
2247 	     * When no index given: "lp->ll_empty2" is TRUE.
2248 	     * Otherwise "lp->ll_n2" is set to the second index.
2249 	     */
2250 	    if (lp->ll_range && !lp->ll_empty2)
2251 	    {
2252 		lp->ll_n2 = (long)tv_get_number(&var2);
2253 						    /* is number or string */
2254 		clear_tv(&var2);
2255 		if (lp->ll_n2 < 0)
2256 		{
2257 		    ni = list_find(lp->ll_list, lp->ll_n2);
2258 		    if (ni == NULL)
2259 		    {
2260 			if (!quiet)
2261 			    semsg(_(e_listidx), lp->ll_n2);
2262 			return NULL;
2263 		    }
2264 		    lp->ll_n2 = list_idx_of_item(lp->ll_list, ni);
2265 		}
2266 
2267 		/* Check that lp->ll_n2 isn't before lp->ll_n1. */
2268 		if (lp->ll_n1 < 0)
2269 		    lp->ll_n1 = list_idx_of_item(lp->ll_list, lp->ll_li);
2270 		if (lp->ll_n2 < lp->ll_n1)
2271 		{
2272 		    if (!quiet)
2273 			semsg(_(e_listidx), lp->ll_n2);
2274 		    return NULL;
2275 		}
2276 	    }
2277 
2278 	    lp->ll_tv = &lp->ll_li->li_tv;
2279 	}
2280     }
2281 
2282     clear_tv(&var1);
2283     return p;
2284 }
2285 
2286 /*
2287  * Clear lval "lp" that was filled by get_lval().
2288  */
2289     void
2290 clear_lval(lval_T *lp)
2291 {
2292     vim_free(lp->ll_exp_name);
2293     vim_free(lp->ll_newkey);
2294 }
2295 
2296 /*
2297  * Set a variable that was parsed by get_lval() to "rettv".
2298  * "endp" points to just after the parsed name.
2299  * "op" is NULL, "+" for "+=", "-" for "-=", "*" for "*=", "/" for "/=",
2300  * "%" for "%=", "." for ".=" or "=" for "=".
2301  */
2302     static void
2303 set_var_lval(
2304     lval_T	*lp,
2305     char_u	*endp,
2306     typval_T	*rettv,
2307     int		copy,
2308     char_u	*op)
2309 {
2310     int		cc;
2311     listitem_T	*ri;
2312     dictitem_T	*di;
2313 
2314     if (lp->ll_tv == NULL)
2315     {
2316 	cc = *endp;
2317 	*endp = NUL;
2318 	if (lp->ll_blob != NULL)
2319 	{
2320 	    int	    error = FALSE, val;
2321 
2322 	    if (op != NULL && *op != '=')
2323 	    {
2324 		semsg(_(e_letwrong), op);
2325 		return;
2326 	    }
2327 
2328 	    if (lp->ll_range && rettv->v_type == VAR_BLOB)
2329 	    {
2330 		int	il, ir;
2331 
2332 		if (lp->ll_empty2)
2333 		    lp->ll_n2 = blob_len(lp->ll_blob) - 1;
2334 
2335 		if (lp->ll_n2 - lp->ll_n1 + 1 != blob_len(rettv->vval.v_blob))
2336 		{
2337 		    emsg(_("E972: Blob value does not have the right number of bytes"));
2338 		    return;
2339 		}
2340 		if (lp->ll_empty2)
2341 		    lp->ll_n2 = blob_len(lp->ll_blob);
2342 
2343 		ir = 0;
2344 		for (il = lp->ll_n1; il <= lp->ll_n2; il++)
2345 		    blob_set(lp->ll_blob, il,
2346 			    blob_get(rettv->vval.v_blob, ir++));
2347 	    }
2348 	    else
2349 	    {
2350 		val = (int)tv_get_number_chk(rettv, &error);
2351 		if (!error)
2352 		{
2353 		    garray_T *gap = &lp->ll_blob->bv_ga;
2354 
2355 		    // Allow for appending a byte.  Setting a byte beyond
2356 		    // the end is an error otherwise.
2357 		    if (lp->ll_n1 < gap->ga_len
2358 			    || (lp->ll_n1 == gap->ga_len
2359 				&& ga_grow(&lp->ll_blob->bv_ga, 1) == OK))
2360 		    {
2361 			blob_set(lp->ll_blob, lp->ll_n1, val);
2362 			if (lp->ll_n1 == gap->ga_len)
2363 			    ++gap->ga_len;
2364 		    }
2365 		    // error for invalid range was already given in get_lval()
2366 		}
2367 	    }
2368 	}
2369 	else if (op != NULL && *op != '=')
2370 	{
2371 	    typval_T tv;
2372 
2373 	    // handle +=, -=, *=, /=, %= and .=
2374 	    di = NULL;
2375 	    if (get_var_tv(lp->ll_name, (int)STRLEN(lp->ll_name),
2376 					     &tv, &di, TRUE, FALSE) == OK)
2377 	    {
2378 		if ((di == NULL
2379 			 || (!var_check_ro(di->di_flags, lp->ll_name, FALSE)
2380 			   && !tv_check_lock(&di->di_tv, lp->ll_name, FALSE)))
2381 			&& tv_op(&tv, rettv, op) == OK)
2382 		    set_var(lp->ll_name, &tv, FALSE);
2383 		clear_tv(&tv);
2384 	    }
2385 	}
2386 	else
2387 	    set_var(lp->ll_name, rettv, copy);
2388 	*endp = cc;
2389     }
2390     else if (var_check_lock(lp->ll_newkey == NULL
2391 		? lp->ll_tv->v_lock
2392 		: lp->ll_tv->vval.v_dict->dv_lock, lp->ll_name, FALSE))
2393 	;
2394     else if (lp->ll_range)
2395     {
2396 	listitem_T *ll_li = lp->ll_li;
2397 	int	    ll_n1 = lp->ll_n1;
2398 
2399 	/*
2400 	 * Check whether any of the list items is locked
2401 	 */
2402 	for (ri = rettv->vval.v_list->lv_first; ri != NULL && ll_li != NULL; )
2403 	{
2404 	    if (var_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
2405 		return;
2406 	    ri = ri->li_next;
2407 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == ll_n1))
2408 		break;
2409 	    ll_li = ll_li->li_next;
2410 	    ++ll_n1;
2411 	}
2412 
2413 	/*
2414 	 * Assign the List values to the list items.
2415 	 */
2416 	for (ri = rettv->vval.v_list->lv_first; ri != NULL; )
2417 	{
2418 	    if (op != NULL && *op != '=')
2419 		tv_op(&lp->ll_li->li_tv, &ri->li_tv, op);
2420 	    else
2421 	    {
2422 		clear_tv(&lp->ll_li->li_tv);
2423 		copy_tv(&ri->li_tv, &lp->ll_li->li_tv);
2424 	    }
2425 	    ri = ri->li_next;
2426 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == lp->ll_n1))
2427 		break;
2428 	    if (lp->ll_li->li_next == NULL)
2429 	    {
2430 		/* Need to add an empty item. */
2431 		if (list_append_number(lp->ll_list, 0) == FAIL)
2432 		{
2433 		    ri = NULL;
2434 		    break;
2435 		}
2436 	    }
2437 	    lp->ll_li = lp->ll_li->li_next;
2438 	    ++lp->ll_n1;
2439 	}
2440 	if (ri != NULL)
2441 	    emsg(_("E710: List value has more items than target"));
2442 	else if (lp->ll_empty2
2443 		? (lp->ll_li != NULL && lp->ll_li->li_next != NULL)
2444 		: lp->ll_n1 != lp->ll_n2)
2445 	    emsg(_("E711: List value has not enough items"));
2446     }
2447     else
2448     {
2449 	/*
2450 	 * Assign to a List or Dictionary item.
2451 	 */
2452 	if (lp->ll_newkey != NULL)
2453 	{
2454 	    if (op != NULL && *op != '=')
2455 	    {
2456 		semsg(_(e_letwrong), op);
2457 		return;
2458 	    }
2459 
2460 	    /* Need to add an item to the Dictionary. */
2461 	    di = dictitem_alloc(lp->ll_newkey);
2462 	    if (di == NULL)
2463 		return;
2464 	    if (dict_add(lp->ll_tv->vval.v_dict, di) == FAIL)
2465 	    {
2466 		vim_free(di);
2467 		return;
2468 	    }
2469 	    lp->ll_tv = &di->di_tv;
2470 	}
2471 	else if (op != NULL && *op != '=')
2472 	{
2473 	    tv_op(lp->ll_tv, rettv, op);
2474 	    return;
2475 	}
2476 	else
2477 	    clear_tv(lp->ll_tv);
2478 
2479 	/*
2480 	 * Assign the value to the variable or list item.
2481 	 */
2482 	if (copy)
2483 	    copy_tv(rettv, lp->ll_tv);
2484 	else
2485 	{
2486 	    *lp->ll_tv = *rettv;
2487 	    lp->ll_tv->v_lock = 0;
2488 	    init_tv(rettv);
2489 	}
2490     }
2491 }
2492 
2493 /*
2494  * Handle "tv1 += tv2", "tv1 -= tv2", "tv1 *= tv2", "tv1 /= tv2", "tv1 %= tv2"
2495  * and "tv1 .= tv2"
2496  * Returns OK or FAIL.
2497  */
2498     static int
2499 tv_op(typval_T *tv1, typval_T *tv2, char_u *op)
2500 {
2501     varnumber_T	n;
2502     char_u	numbuf[NUMBUFLEN];
2503     char_u	*s;
2504 
2505     /* Can't do anything with a Funcref, Dict, v:true on the right. */
2506     if (tv2->v_type != VAR_FUNC && tv2->v_type != VAR_DICT
2507 						&& tv2->v_type != VAR_SPECIAL)
2508     {
2509 	switch (tv1->v_type)
2510 	{
2511 	    case VAR_UNKNOWN:
2512 	    case VAR_DICT:
2513 	    case VAR_FUNC:
2514 	    case VAR_PARTIAL:
2515 	    case VAR_SPECIAL:
2516 	    case VAR_JOB:
2517 	    case VAR_CHANNEL:
2518 		break;
2519 
2520 	    case VAR_BLOB:
2521 		if (*op != '+' || tv2->v_type != VAR_BLOB)
2522 		    break;
2523 		// BLOB += BLOB
2524 		if (tv1->vval.v_blob != NULL && tv2->vval.v_blob != NULL)
2525 		{
2526 		    blob_T  *b1 = tv1->vval.v_blob;
2527 		    blob_T  *b2 = tv2->vval.v_blob;
2528 		    int	i, len = blob_len(b2);
2529 		    for (i = 0; i < len; i++)
2530 			ga_append(&b1->bv_ga, blob_get(b2, i));
2531 		}
2532 		return OK;
2533 
2534 	    case VAR_LIST:
2535 		if (*op != '+' || tv2->v_type != VAR_LIST)
2536 		    break;
2537 		// List += List
2538 		if (tv1->vval.v_list != NULL && tv2->vval.v_list != NULL)
2539 		    list_extend(tv1->vval.v_list, tv2->vval.v_list, NULL);
2540 		return OK;
2541 
2542 	    case VAR_NUMBER:
2543 	    case VAR_STRING:
2544 		if (tv2->v_type == VAR_LIST)
2545 		    break;
2546 		if (vim_strchr((char_u *)"+-*/%", *op) != NULL)
2547 		{
2548 		    // nr += nr , nr -= nr , nr *=nr , nr /= nr , nr %= nr
2549 		    n = tv_get_number(tv1);
2550 #ifdef FEAT_FLOAT
2551 		    if (tv2->v_type == VAR_FLOAT)
2552 		    {
2553 			float_T f = n;
2554 
2555 			if (*op == '%')
2556 			    break;
2557 			switch (*op)
2558 			{
2559 			    case '+': f += tv2->vval.v_float; break;
2560 			    case '-': f -= tv2->vval.v_float; break;
2561 			    case '*': f *= tv2->vval.v_float; break;
2562 			    case '/': f /= tv2->vval.v_float; break;
2563 			}
2564 			clear_tv(tv1);
2565 			tv1->v_type = VAR_FLOAT;
2566 			tv1->vval.v_float = f;
2567 		    }
2568 		    else
2569 #endif
2570 		    {
2571 			switch (*op)
2572 			{
2573 			    case '+': n += tv_get_number(tv2); break;
2574 			    case '-': n -= tv_get_number(tv2); break;
2575 			    case '*': n *= tv_get_number(tv2); break;
2576 			    case '/': n = num_divide(n, tv_get_number(tv2)); break;
2577 			    case '%': n = num_modulus(n, tv_get_number(tv2)); break;
2578 			}
2579 			clear_tv(tv1);
2580 			tv1->v_type = VAR_NUMBER;
2581 			tv1->vval.v_number = n;
2582 		    }
2583 		}
2584 		else
2585 		{
2586 		    if (tv2->v_type == VAR_FLOAT)
2587 			break;
2588 
2589 		    // str .= str
2590 		    s = tv_get_string(tv1);
2591 		    s = concat_str(s, tv_get_string_buf(tv2, numbuf));
2592 		    clear_tv(tv1);
2593 		    tv1->v_type = VAR_STRING;
2594 		    tv1->vval.v_string = s;
2595 		}
2596 		return OK;
2597 
2598 	    case VAR_FLOAT:
2599 #ifdef FEAT_FLOAT
2600 		{
2601 		    float_T f;
2602 
2603 		    if (*op == '%' || *op == '.'
2604 				   || (tv2->v_type != VAR_FLOAT
2605 				    && tv2->v_type != VAR_NUMBER
2606 				    && tv2->v_type != VAR_STRING))
2607 			break;
2608 		    if (tv2->v_type == VAR_FLOAT)
2609 			f = tv2->vval.v_float;
2610 		    else
2611 			f = tv_get_number(tv2);
2612 		    switch (*op)
2613 		    {
2614 			case '+': tv1->vval.v_float += f; break;
2615 			case '-': tv1->vval.v_float -= f; break;
2616 			case '*': tv1->vval.v_float *= f; break;
2617 			case '/': tv1->vval.v_float /= f; break;
2618 		    }
2619 		}
2620 #endif
2621 		return OK;
2622 	}
2623     }
2624 
2625     semsg(_(e_letwrong), op);
2626     return FAIL;
2627 }
2628 
2629 /*
2630  * Evaluate the expression used in a ":for var in expr" command.
2631  * "arg" points to "var".
2632  * Set "*errp" to TRUE for an error, FALSE otherwise;
2633  * Return a pointer that holds the info.  Null when there is an error.
2634  */
2635     void *
2636 eval_for_line(
2637     char_u	*arg,
2638     int		*errp,
2639     char_u	**nextcmdp,
2640     int		skip)
2641 {
2642     forinfo_T	*fi;
2643     char_u	*expr;
2644     typval_T	tv;
2645     list_T	*l;
2646 
2647     *errp = TRUE;	/* default: there is an error */
2648 
2649     fi = (forinfo_T *)alloc_clear(sizeof(forinfo_T));
2650     if (fi == NULL)
2651 	return NULL;
2652 
2653     expr = skip_var_list(arg, &fi->fi_varcount, &fi->fi_semicolon);
2654     if (expr == NULL)
2655 	return fi;
2656 
2657     expr = skipwhite(expr);
2658     if (expr[0] != 'i' || expr[1] != 'n' || !VIM_ISWHITE(expr[2]))
2659     {
2660 	emsg(_("E690: Missing \"in\" after :for"));
2661 	return fi;
2662     }
2663 
2664     if (skip)
2665 	++emsg_skip;
2666     if (eval0(skipwhite(expr + 2), &tv, nextcmdp, !skip) == OK)
2667     {
2668 	*errp = FALSE;
2669 	if (!skip)
2670 	{
2671 	    if (tv.v_type == VAR_LIST)
2672 	    {
2673 		l = tv.vval.v_list;
2674 		if (l == NULL)
2675 		{
2676 		    // a null list is like an empty list: do nothing
2677 		    clear_tv(&tv);
2678 		}
2679 		else
2680 		{
2681 		    // No need to increment the refcount, it's already set for
2682 		    // the list being used in "tv".
2683 		    fi->fi_list = l;
2684 		    list_add_watch(l, &fi->fi_lw);
2685 		    fi->fi_lw.lw_item = l->lv_first;
2686 		}
2687 	    }
2688 	    else if (tv.v_type == VAR_BLOB)
2689 	    {
2690 		fi->fi_bi = 0;
2691 		if (tv.vval.v_blob != NULL)
2692 		{
2693 		    typval_T btv;
2694 
2695 		    // Make a copy, so that the iteration still works when the
2696 		    // blob is changed.
2697 		    blob_copy(&tv, &btv);
2698 		    fi->fi_blob = btv.vval.v_blob;
2699 		}
2700 		clear_tv(&tv);
2701 	    }
2702 	    else
2703 	    {
2704 		emsg(_(e_listreq));
2705 		clear_tv(&tv);
2706 	    }
2707 	}
2708     }
2709     if (skip)
2710 	--emsg_skip;
2711 
2712     return fi;
2713 }
2714 
2715 /*
2716  * Use the first item in a ":for" list.  Advance to the next.
2717  * Assign the values to the variable (list).  "arg" points to the first one.
2718  * Return TRUE when a valid item was found, FALSE when at end of list or
2719  * something wrong.
2720  */
2721     int
2722 next_for_item(void *fi_void, char_u *arg)
2723 {
2724     forinfo_T	*fi = (forinfo_T *)fi_void;
2725     int		result;
2726     listitem_T	*item;
2727 
2728     if (fi->fi_blob != NULL)
2729     {
2730 	typval_T	tv;
2731 
2732 	if (fi->fi_bi >= blob_len(fi->fi_blob))
2733 	    return FALSE;
2734 	tv.v_type = VAR_NUMBER;
2735 	tv.v_lock = VAR_FIXED;
2736 	tv.vval.v_number = blob_get(fi->fi_blob, fi->fi_bi);
2737 	++fi->fi_bi;
2738 	return ex_let_vars(arg, &tv, TRUE,
2739 			      fi->fi_semicolon, fi->fi_varcount, NULL) == OK;
2740     }
2741 
2742     item = fi->fi_lw.lw_item;
2743     if (item == NULL)
2744 	result = FALSE;
2745     else
2746     {
2747 	fi->fi_lw.lw_item = item->li_next;
2748 	result = (ex_let_vars(arg, &item->li_tv, TRUE,
2749 			      fi->fi_semicolon, fi->fi_varcount, NULL) == OK);
2750     }
2751     return result;
2752 }
2753 
2754 /*
2755  * Free the structure used to store info used by ":for".
2756  */
2757     void
2758 free_for_info(void *fi_void)
2759 {
2760     forinfo_T    *fi = (forinfo_T *)fi_void;
2761 
2762     if (fi != NULL && fi->fi_list != NULL)
2763     {
2764 	list_rem_watch(fi->fi_list, &fi->fi_lw);
2765 	list_unref(fi->fi_list);
2766     }
2767     if (fi != NULL && fi->fi_blob != NULL)
2768 	blob_unref(fi->fi_blob);
2769     vim_free(fi);
2770 }
2771 
2772 #if defined(FEAT_CMDL_COMPL) || defined(PROTO)
2773 
2774     void
2775 set_context_for_expression(
2776     expand_T	*xp,
2777     char_u	*arg,
2778     cmdidx_T	cmdidx)
2779 {
2780     int		got_eq = FALSE;
2781     int		c;
2782     char_u	*p;
2783 
2784     if (cmdidx == CMD_let)
2785     {
2786 	xp->xp_context = EXPAND_USER_VARS;
2787 	if (vim_strpbrk(arg, (char_u *)"\"'+-*/%.=!?~|&$([<>,#") == NULL)
2788 	{
2789 	    /* ":let var1 var2 ...": find last space. */
2790 	    for (p = arg + STRLEN(arg); p >= arg; )
2791 	    {
2792 		xp->xp_pattern = p;
2793 		MB_PTR_BACK(arg, p);
2794 		if (VIM_ISWHITE(*p))
2795 		    break;
2796 	    }
2797 	    return;
2798 	}
2799     }
2800     else
2801 	xp->xp_context = cmdidx == CMD_call ? EXPAND_FUNCTIONS
2802 							  : EXPAND_EXPRESSION;
2803     while ((xp->xp_pattern = vim_strpbrk(arg,
2804 				  (char_u *)"\"'+-*/%.=!?~|&$([<>,#")) != NULL)
2805     {
2806 	c = *xp->xp_pattern;
2807 	if (c == '&')
2808 	{
2809 	    c = xp->xp_pattern[1];
2810 	    if (c == '&')
2811 	    {
2812 		++xp->xp_pattern;
2813 		xp->xp_context = cmdidx != CMD_let || got_eq
2814 					 ? EXPAND_EXPRESSION : EXPAND_NOTHING;
2815 	    }
2816 	    else if (c != ' ')
2817 	    {
2818 		xp->xp_context = EXPAND_SETTINGS;
2819 		if ((c == 'l' || c == 'g') && xp->xp_pattern[2] == ':')
2820 		    xp->xp_pattern += 2;
2821 
2822 	    }
2823 	}
2824 	else if (c == '$')
2825 	{
2826 	    /* environment variable */
2827 	    xp->xp_context = EXPAND_ENV_VARS;
2828 	}
2829 	else if (c == '=')
2830 	{
2831 	    got_eq = TRUE;
2832 	    xp->xp_context = EXPAND_EXPRESSION;
2833 	}
2834 	else if (c == '#'
2835 		&& xp->xp_context == EXPAND_EXPRESSION)
2836 	{
2837 	    /* Autoload function/variable contains '#'. */
2838 	    break;
2839 	}
2840 	else if ((c == '<' || c == '#')
2841 		&& xp->xp_context == EXPAND_FUNCTIONS
2842 		&& vim_strchr(xp->xp_pattern, '(') == NULL)
2843 	{
2844 	    /* Function name can start with "<SNR>" and contain '#'. */
2845 	    break;
2846 	}
2847 	else if (cmdidx != CMD_let || got_eq)
2848 	{
2849 	    if (c == '"')	    /* string */
2850 	    {
2851 		while ((c = *++xp->xp_pattern) != NUL && c != '"')
2852 		    if (c == '\\' && xp->xp_pattern[1] != NUL)
2853 			++xp->xp_pattern;
2854 		xp->xp_context = EXPAND_NOTHING;
2855 	    }
2856 	    else if (c == '\'')	    /* literal string */
2857 	    {
2858 		/* Trick: '' is like stopping and starting a literal string. */
2859 		while ((c = *++xp->xp_pattern) != NUL && c != '\'')
2860 		    /* skip */ ;
2861 		xp->xp_context = EXPAND_NOTHING;
2862 	    }
2863 	    else if (c == '|')
2864 	    {
2865 		if (xp->xp_pattern[1] == '|')
2866 		{
2867 		    ++xp->xp_pattern;
2868 		    xp->xp_context = EXPAND_EXPRESSION;
2869 		}
2870 		else
2871 		    xp->xp_context = EXPAND_COMMANDS;
2872 	    }
2873 	    else
2874 		xp->xp_context = EXPAND_EXPRESSION;
2875 	}
2876 	else
2877 	    /* Doesn't look like something valid, expand as an expression
2878 	     * anyway. */
2879 	    xp->xp_context = EXPAND_EXPRESSION;
2880 	arg = xp->xp_pattern;
2881 	if (*arg != NUL)
2882 	    while ((c = *++arg) != NUL && (c == ' ' || c == '\t'))
2883 		/* skip */ ;
2884     }
2885     xp->xp_pattern = arg;
2886 }
2887 
2888 #endif /* FEAT_CMDL_COMPL */
2889 
2890 /*
2891  * ":unlet[!] var1 ... " command.
2892  */
2893     void
2894 ex_unlet(exarg_T *eap)
2895 {
2896     ex_unletlock(eap, eap->arg, 0);
2897 }
2898 
2899 /*
2900  * ":lockvar" and ":unlockvar" commands
2901  */
2902     void
2903 ex_lockvar(exarg_T *eap)
2904 {
2905     char_u	*arg = eap->arg;
2906     int		deep = 2;
2907 
2908     if (eap->forceit)
2909 	deep = -1;
2910     else if (vim_isdigit(*arg))
2911     {
2912 	deep = getdigits(&arg);
2913 	arg = skipwhite(arg);
2914     }
2915 
2916     ex_unletlock(eap, arg, deep);
2917 }
2918 
2919 /*
2920  * ":unlet", ":lockvar" and ":unlockvar" are quite similar.
2921  */
2922     static void
2923 ex_unletlock(
2924     exarg_T	*eap,
2925     char_u	*argstart,
2926     int		deep)
2927 {
2928     char_u	*arg = argstart;
2929     char_u	*name_end;
2930     int		error = FALSE;
2931     lval_T	lv;
2932 
2933     do
2934     {
2935 	if (*arg == '$')
2936 	{
2937 	    char_u    *name = ++arg;
2938 
2939 	    if (get_env_len(&arg) == 0)
2940 	    {
2941 		semsg(_(e_invarg2), name - 1);
2942 		return;
2943 	    }
2944 	    vim_unsetenv(name);
2945 	    arg = skipwhite(arg);
2946 	    continue;
2947 	}
2948 
2949 	/* Parse the name and find the end. */
2950 	name_end = get_lval(arg, NULL, &lv, TRUE, eap->skip || error, 0,
2951 							     FNE_CHECK_START);
2952 	if (lv.ll_name == NULL)
2953 	    error = TRUE;	    /* error but continue parsing */
2954 	if (name_end == NULL || (!VIM_ISWHITE(*name_end)
2955 						   && !ends_excmd(*name_end)))
2956 	{
2957 	    if (name_end != NULL)
2958 	    {
2959 		emsg_severe = TRUE;
2960 		emsg(_(e_trailing));
2961 	    }
2962 	    if (!(eap->skip || error))
2963 		clear_lval(&lv);
2964 	    break;
2965 	}
2966 
2967 	if (!error && !eap->skip)
2968 	{
2969 	    if (eap->cmdidx == CMD_unlet)
2970 	    {
2971 		if (do_unlet_var(&lv, name_end, eap->forceit) == FAIL)
2972 		    error = TRUE;
2973 	    }
2974 	    else
2975 	    {
2976 		if (do_lock_var(&lv, name_end, deep,
2977 					  eap->cmdidx == CMD_lockvar) == FAIL)
2978 		    error = TRUE;
2979 	    }
2980 	}
2981 
2982 	if (!eap->skip)
2983 	    clear_lval(&lv);
2984 
2985 	arg = skipwhite(name_end);
2986     } while (!ends_excmd(*arg));
2987 
2988     eap->nextcmd = check_nextcmd(arg);
2989 }
2990 
2991     static int
2992 do_unlet_var(
2993     lval_T	*lp,
2994     char_u	*name_end,
2995     int		forceit)
2996 {
2997     int		ret = OK;
2998     int		cc;
2999 
3000     if (lp->ll_tv == NULL)
3001     {
3002 	cc = *name_end;
3003 	*name_end = NUL;
3004 
3005 	/* Normal name or expanded name. */
3006 	if (do_unlet(lp->ll_name, forceit) == FAIL)
3007 	    ret = FAIL;
3008 	*name_end = cc;
3009     }
3010     else if ((lp->ll_list != NULL
3011 		 && var_check_lock(lp->ll_list->lv_lock, lp->ll_name, FALSE))
3012 	    || (lp->ll_dict != NULL
3013 		 && var_check_lock(lp->ll_dict->dv_lock, lp->ll_name, FALSE)))
3014 	return FAIL;
3015     else if (lp->ll_range)
3016     {
3017 	listitem_T    *li;
3018 	listitem_T    *ll_li = lp->ll_li;
3019 	int	      ll_n1 = lp->ll_n1;
3020 
3021 	while (ll_li != NULL && (lp->ll_empty2 || lp->ll_n2 >= ll_n1))
3022 	{
3023 	    li = ll_li->li_next;
3024 	    if (var_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
3025 		return FAIL;
3026 	    ll_li = li;
3027 	    ++ll_n1;
3028 	}
3029 
3030 	/* Delete a range of List items. */
3031 	while (lp->ll_li != NULL && (lp->ll_empty2 || lp->ll_n2 >= lp->ll_n1))
3032 	{
3033 	    li = lp->ll_li->li_next;
3034 	    listitem_remove(lp->ll_list, lp->ll_li);
3035 	    lp->ll_li = li;
3036 	    ++lp->ll_n1;
3037 	}
3038     }
3039     else
3040     {
3041 	if (lp->ll_list != NULL)
3042 	    /* unlet a List item. */
3043 	    listitem_remove(lp->ll_list, lp->ll_li);
3044 	else
3045 	    /* unlet a Dictionary item. */
3046 	    dictitem_remove(lp->ll_dict, lp->ll_di);
3047     }
3048 
3049     return ret;
3050 }
3051 
3052 /*
3053  * "unlet" a variable.  Return OK if it existed, FAIL if not.
3054  * When "forceit" is TRUE don't complain if the variable doesn't exist.
3055  */
3056     int
3057 do_unlet(char_u *name, int forceit)
3058 {
3059     hashtab_T	*ht;
3060     hashitem_T	*hi;
3061     char_u	*varname;
3062     dict_T	*d;
3063     dictitem_T	*di;
3064 
3065     ht = find_var_ht(name, &varname);
3066     if (ht != NULL && *varname != NUL)
3067     {
3068 	d = get_current_funccal_dict(ht);
3069 	if (d == NULL)
3070 	{
3071 	    if (ht == &globvarht)
3072 		d = &globvardict;
3073 	    else if (ht == &compat_hashtab)
3074 		d = &vimvardict;
3075 	    else
3076 	    {
3077 		di = find_var_in_ht(ht, *name, (char_u *)"", FALSE);
3078 		d = di == NULL ? NULL : di->di_tv.vval.v_dict;
3079 	    }
3080 	    if (d == NULL)
3081 	    {
3082 		internal_error("do_unlet()");
3083 		return FAIL;
3084 	    }
3085 	}
3086 	hi = hash_find(ht, varname);
3087 	if (HASHITEM_EMPTY(hi))
3088 	    hi = find_hi_in_scoped_ht(name, &ht);
3089 	if (hi != NULL && !HASHITEM_EMPTY(hi))
3090 	{
3091 	    di = HI2DI(hi);
3092 	    if (var_check_fixed(di->di_flags, name, FALSE)
3093 		    || var_check_ro(di->di_flags, name, FALSE)
3094 		    || var_check_lock(d->dv_lock, name, FALSE))
3095 		return FAIL;
3096 
3097 	    delete_var(ht, hi);
3098 	    return OK;
3099 	}
3100     }
3101     if (forceit)
3102 	return OK;
3103     semsg(_("E108: No such variable: \"%s\""), name);
3104     return FAIL;
3105 }
3106 
3107 /*
3108  * Lock or unlock variable indicated by "lp".
3109  * "deep" is the levels to go (-1 for unlimited);
3110  * "lock" is TRUE for ":lockvar", FALSE for ":unlockvar".
3111  */
3112     static int
3113 do_lock_var(
3114     lval_T	*lp,
3115     char_u	*name_end,
3116     int		deep,
3117     int		lock)
3118 {
3119     int		ret = OK;
3120     int		cc;
3121     dictitem_T	*di;
3122 
3123     if (deep == 0)	/* nothing to do */
3124 	return OK;
3125 
3126     if (lp->ll_tv == NULL)
3127     {
3128 	cc = *name_end;
3129 	*name_end = NUL;
3130 
3131 	/* Normal name or expanded name. */
3132 	di = find_var(lp->ll_name, NULL, TRUE);
3133 	if (di == NULL)
3134 	    ret = FAIL;
3135 	else if ((di->di_flags & DI_FLAGS_FIX)
3136 			&& di->di_tv.v_type != VAR_DICT
3137 			&& di->di_tv.v_type != VAR_LIST)
3138 	    /* For historic reasons this error is not given for a list or dict.
3139 	     * E.g., the b: dict could be locked/unlocked. */
3140 	    semsg(_("E940: Cannot lock or unlock variable %s"), lp->ll_name);
3141 	else
3142 	{
3143 	    if (lock)
3144 		di->di_flags |= DI_FLAGS_LOCK;
3145 	    else
3146 		di->di_flags &= ~DI_FLAGS_LOCK;
3147 	    item_lock(&di->di_tv, deep, lock);
3148 	}
3149 	*name_end = cc;
3150     }
3151     else if (lp->ll_range)
3152     {
3153 	listitem_T    *li = lp->ll_li;
3154 
3155 	/* (un)lock a range of List items. */
3156 	while (li != NULL && (lp->ll_empty2 || lp->ll_n2 >= lp->ll_n1))
3157 	{
3158 	    item_lock(&li->li_tv, deep, lock);
3159 	    li = li->li_next;
3160 	    ++lp->ll_n1;
3161 	}
3162     }
3163     else if (lp->ll_list != NULL)
3164 	/* (un)lock a List item. */
3165 	item_lock(&lp->ll_li->li_tv, deep, lock);
3166     else
3167 	/* (un)lock a Dictionary item. */
3168 	item_lock(&lp->ll_di->di_tv, deep, lock);
3169 
3170     return ret;
3171 }
3172 
3173 /*
3174  * Lock or unlock an item.  "deep" is nr of levels to go.
3175  */
3176     static void
3177 item_lock(typval_T *tv, int deep, int lock)
3178 {
3179     static int	recurse = 0;
3180     list_T	*l;
3181     listitem_T	*li;
3182     dict_T	*d;
3183     blob_T	*b;
3184     hashitem_T	*hi;
3185     int		todo;
3186 
3187     if (recurse >= DICT_MAXNEST)
3188     {
3189 	emsg(_("E743: variable nested too deep for (un)lock"));
3190 	return;
3191     }
3192     if (deep == 0)
3193 	return;
3194     ++recurse;
3195 
3196     /* lock/unlock the item itself */
3197     if (lock)
3198 	tv->v_lock |= VAR_LOCKED;
3199     else
3200 	tv->v_lock &= ~VAR_LOCKED;
3201 
3202     switch (tv->v_type)
3203     {
3204 	case VAR_UNKNOWN:
3205 	case VAR_NUMBER:
3206 	case VAR_STRING:
3207 	case VAR_FUNC:
3208 	case VAR_PARTIAL:
3209 	case VAR_FLOAT:
3210 	case VAR_SPECIAL:
3211 	case VAR_JOB:
3212 	case VAR_CHANNEL:
3213 	    break;
3214 
3215 	case VAR_BLOB:
3216 	    if ((b = tv->vval.v_blob) != NULL)
3217 	    {
3218 		if (lock)
3219 		    b->bv_lock |= VAR_LOCKED;
3220 		else
3221 		    b->bv_lock &= ~VAR_LOCKED;
3222 	    }
3223 	    break;
3224 	case VAR_LIST:
3225 	    if ((l = tv->vval.v_list) != NULL)
3226 	    {
3227 		if (lock)
3228 		    l->lv_lock |= VAR_LOCKED;
3229 		else
3230 		    l->lv_lock &= ~VAR_LOCKED;
3231 		if (deep < 0 || deep > 1)
3232 		    /* recursive: lock/unlock the items the List contains */
3233 		    for (li = l->lv_first; li != NULL; li = li->li_next)
3234 			item_lock(&li->li_tv, deep - 1, lock);
3235 	    }
3236 	    break;
3237 	case VAR_DICT:
3238 	    if ((d = tv->vval.v_dict) != NULL)
3239 	    {
3240 		if (lock)
3241 		    d->dv_lock |= VAR_LOCKED;
3242 		else
3243 		    d->dv_lock &= ~VAR_LOCKED;
3244 		if (deep < 0 || deep > 1)
3245 		{
3246 		    /* recursive: lock/unlock the items the List contains */
3247 		    todo = (int)d->dv_hashtab.ht_used;
3248 		    for (hi = d->dv_hashtab.ht_array; todo > 0; ++hi)
3249 		    {
3250 			if (!HASHITEM_EMPTY(hi))
3251 			{
3252 			    --todo;
3253 			    item_lock(&HI2DI(hi)->di_tv, deep - 1, lock);
3254 			}
3255 		    }
3256 		}
3257 	    }
3258     }
3259     --recurse;
3260 }
3261 
3262 #if (defined(FEAT_MENU) && defined(FEAT_MULTI_LANG)) || defined(PROTO)
3263 /*
3264  * Delete all "menutrans_" variables.
3265  */
3266     void
3267 del_menutrans_vars(void)
3268 {
3269     hashitem_T	*hi;
3270     int		todo;
3271 
3272     hash_lock(&globvarht);
3273     todo = (int)globvarht.ht_used;
3274     for (hi = globvarht.ht_array; todo > 0 && !got_int; ++hi)
3275     {
3276 	if (!HASHITEM_EMPTY(hi))
3277 	{
3278 	    --todo;
3279 	    if (STRNCMP(HI2DI(hi)->di_key, "menutrans_", 10) == 0)
3280 		delete_var(&globvarht, hi);
3281 	}
3282     }
3283     hash_unlock(&globvarht);
3284 }
3285 #endif
3286 
3287 #if defined(FEAT_CMDL_COMPL) || defined(PROTO)
3288 
3289 /*
3290  * Local string buffer for the next two functions to store a variable name
3291  * with its prefix. Allocated in cat_prefix_varname(), freed later in
3292  * get_user_var_name().
3293  */
3294 
3295 static char_u	*varnamebuf = NULL;
3296 static int	varnamebuflen = 0;
3297 
3298 /*
3299  * Function to concatenate a prefix and a variable name.
3300  */
3301     static char_u *
3302 cat_prefix_varname(int prefix, char_u *name)
3303 {
3304     int		len;
3305 
3306     len = (int)STRLEN(name) + 3;
3307     if (len > varnamebuflen)
3308     {
3309 	vim_free(varnamebuf);
3310 	len += 10;			/* some additional space */
3311 	varnamebuf = alloc(len);
3312 	if (varnamebuf == NULL)
3313 	{
3314 	    varnamebuflen = 0;
3315 	    return NULL;
3316 	}
3317 	varnamebuflen = len;
3318     }
3319     *varnamebuf = prefix;
3320     varnamebuf[1] = ':';
3321     STRCPY(varnamebuf + 2, name);
3322     return varnamebuf;
3323 }
3324 
3325 /*
3326  * Function given to ExpandGeneric() to obtain the list of user defined
3327  * (global/buffer/window/built-in) variable names.
3328  */
3329     char_u *
3330 get_user_var_name(expand_T *xp, int idx)
3331 {
3332     static long_u	gdone;
3333     static long_u	bdone;
3334     static long_u	wdone;
3335     static long_u	tdone;
3336     static int		vidx;
3337     static hashitem_T	*hi;
3338     hashtab_T		*ht;
3339 
3340     if (idx == 0)
3341     {
3342 	gdone = bdone = wdone = vidx = 0;
3343 	tdone = 0;
3344     }
3345 
3346     /* Global variables */
3347     if (gdone < globvarht.ht_used)
3348     {
3349 	if (gdone++ == 0)
3350 	    hi = globvarht.ht_array;
3351 	else
3352 	    ++hi;
3353 	while (HASHITEM_EMPTY(hi))
3354 	    ++hi;
3355 	if (STRNCMP("g:", xp->xp_pattern, 2) == 0)
3356 	    return cat_prefix_varname('g', hi->hi_key);
3357 	return hi->hi_key;
3358     }
3359 
3360     /* b: variables */
3361     ht = &curbuf->b_vars->dv_hashtab;
3362     if (bdone < ht->ht_used)
3363     {
3364 	if (bdone++ == 0)
3365 	    hi = ht->ht_array;
3366 	else
3367 	    ++hi;
3368 	while (HASHITEM_EMPTY(hi))
3369 	    ++hi;
3370 	return cat_prefix_varname('b', hi->hi_key);
3371     }
3372 
3373     /* w: variables */
3374     ht = &curwin->w_vars->dv_hashtab;
3375     if (wdone < ht->ht_used)
3376     {
3377 	if (wdone++ == 0)
3378 	    hi = ht->ht_array;
3379 	else
3380 	    ++hi;
3381 	while (HASHITEM_EMPTY(hi))
3382 	    ++hi;
3383 	return cat_prefix_varname('w', hi->hi_key);
3384     }
3385 
3386     /* t: variables */
3387     ht = &curtab->tp_vars->dv_hashtab;
3388     if (tdone < ht->ht_used)
3389     {
3390 	if (tdone++ == 0)
3391 	    hi = ht->ht_array;
3392 	else
3393 	    ++hi;
3394 	while (HASHITEM_EMPTY(hi))
3395 	    ++hi;
3396 	return cat_prefix_varname('t', hi->hi_key);
3397     }
3398 
3399     /* v: variables */
3400     if (vidx < VV_LEN)
3401 	return cat_prefix_varname('v', (char_u *)vimvars[vidx++].vv_name);
3402 
3403     VIM_CLEAR(varnamebuf);
3404     varnamebuflen = 0;
3405     return NULL;
3406 }
3407 
3408 #endif /* FEAT_CMDL_COMPL */
3409 
3410 /*
3411  * Return TRUE if "pat" matches "text".
3412  * Does not use 'cpo' and always uses 'magic'.
3413  */
3414     static int
3415 pattern_match(char_u *pat, char_u *text, int ic)
3416 {
3417     int		matches = FALSE;
3418     char_u	*save_cpo;
3419     regmatch_T	regmatch;
3420 
3421     /* avoid 'l' flag in 'cpoptions' */
3422     save_cpo = p_cpo;
3423     p_cpo = (char_u *)"";
3424     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
3425     if (regmatch.regprog != NULL)
3426     {
3427 	regmatch.rm_ic = ic;
3428 	matches = vim_regexec_nl(&regmatch, text, (colnr_T)0);
3429 	vim_regfree(regmatch.regprog);
3430     }
3431     p_cpo = save_cpo;
3432     return matches;
3433 }
3434 
3435 /*
3436  * The "evaluate" argument: When FALSE, the argument is only parsed but not
3437  * executed.  The function may return OK, but the rettv will be of type
3438  * VAR_UNKNOWN.  The function still returns FAIL for a syntax error.
3439  */
3440 
3441 /*
3442  * Handle zero level expression.
3443  * This calls eval1() and handles error message and nextcmd.
3444  * Put the result in "rettv" when returning OK and "evaluate" is TRUE.
3445  * Note: "rettv.v_lock" is not set.
3446  * Return OK or FAIL.
3447  */
3448     int
3449 eval0(
3450     char_u	*arg,
3451     typval_T	*rettv,
3452     char_u	**nextcmd,
3453     int		evaluate)
3454 {
3455     int		ret;
3456     char_u	*p;
3457     int		did_emsg_before = did_emsg;
3458     int		called_emsg_before = called_emsg;
3459 
3460     p = skipwhite(arg);
3461     ret = eval1(&p, rettv, evaluate);
3462     if (ret == FAIL || !ends_excmd(*p))
3463     {
3464 	if (ret != FAIL)
3465 	    clear_tv(rettv);
3466 	/*
3467 	 * Report the invalid expression unless the expression evaluation has
3468 	 * been cancelled due to an aborting error, an interrupt, or an
3469 	 * exception, or we already gave a more specific error.
3470 	 * Also check called_emsg for when using assert_fails().
3471 	 */
3472 	if (!aborting() && did_emsg == did_emsg_before
3473 					  && called_emsg == called_emsg_before)
3474 	    semsg(_(e_invexpr2), arg);
3475 	ret = FAIL;
3476     }
3477     if (nextcmd != NULL)
3478 	*nextcmd = check_nextcmd(p);
3479 
3480     return ret;
3481 }
3482 
3483 /*
3484  * Handle top level expression:
3485  *	expr2 ? expr1 : expr1
3486  *
3487  * "arg" must point to the first non-white of the expression.
3488  * "arg" is advanced to the next non-white after the recognized expression.
3489  *
3490  * Note: "rettv.v_lock" is not set.
3491  *
3492  * Return OK or FAIL.
3493  */
3494     int
3495 eval1(char_u **arg, typval_T *rettv, int evaluate)
3496 {
3497     int		result;
3498     typval_T	var2;
3499 
3500     /*
3501      * Get the first variable.
3502      */
3503     if (eval2(arg, rettv, evaluate) == FAIL)
3504 	return FAIL;
3505 
3506     if ((*arg)[0] == '?')
3507     {
3508 	result = FALSE;
3509 	if (evaluate)
3510 	{
3511 	    int		error = FALSE;
3512 
3513 	    if (tv_get_number_chk(rettv, &error) != 0)
3514 		result = TRUE;
3515 	    clear_tv(rettv);
3516 	    if (error)
3517 		return FAIL;
3518 	}
3519 
3520 	/*
3521 	 * Get the second variable.
3522 	 */
3523 	*arg = skipwhite(*arg + 1);
3524 	if (eval1(arg, rettv, evaluate && result) == FAIL) /* recursive! */
3525 	    return FAIL;
3526 
3527 	/*
3528 	 * Check for the ":".
3529 	 */
3530 	if ((*arg)[0] != ':')
3531 	{
3532 	    emsg(_("E109: Missing ':' after '?'"));
3533 	    if (evaluate && result)
3534 		clear_tv(rettv);
3535 	    return FAIL;
3536 	}
3537 
3538 	/*
3539 	 * Get the third variable.
3540 	 */
3541 	*arg = skipwhite(*arg + 1);
3542 	if (eval1(arg, &var2, evaluate && !result) == FAIL) /* recursive! */
3543 	{
3544 	    if (evaluate && result)
3545 		clear_tv(rettv);
3546 	    return FAIL;
3547 	}
3548 	if (evaluate && !result)
3549 	    *rettv = var2;
3550     }
3551 
3552     return OK;
3553 }
3554 
3555 /*
3556  * Handle first level expression:
3557  *	expr2 || expr2 || expr2	    logical OR
3558  *
3559  * "arg" must point to the first non-white of the expression.
3560  * "arg" is advanced to the next non-white after the recognized expression.
3561  *
3562  * Return OK or FAIL.
3563  */
3564     static int
3565 eval2(char_u **arg, typval_T *rettv, int evaluate)
3566 {
3567     typval_T	var2;
3568     long	result;
3569     int		first;
3570     int		error = FALSE;
3571 
3572     /*
3573      * Get the first variable.
3574      */
3575     if (eval3(arg, rettv, evaluate) == FAIL)
3576 	return FAIL;
3577 
3578     /*
3579      * Repeat until there is no following "||".
3580      */
3581     first = TRUE;
3582     result = FALSE;
3583     while ((*arg)[0] == '|' && (*arg)[1] == '|')
3584     {
3585 	if (evaluate && first)
3586 	{
3587 	    if (tv_get_number_chk(rettv, &error) != 0)
3588 		result = TRUE;
3589 	    clear_tv(rettv);
3590 	    if (error)
3591 		return FAIL;
3592 	    first = FALSE;
3593 	}
3594 
3595 	/*
3596 	 * Get the second variable.
3597 	 */
3598 	*arg = skipwhite(*arg + 2);
3599 	if (eval3(arg, &var2, evaluate && !result) == FAIL)
3600 	    return FAIL;
3601 
3602 	/*
3603 	 * Compute the result.
3604 	 */
3605 	if (evaluate && !result)
3606 	{
3607 	    if (tv_get_number_chk(&var2, &error) != 0)
3608 		result = TRUE;
3609 	    clear_tv(&var2);
3610 	    if (error)
3611 		return FAIL;
3612 	}
3613 	if (evaluate)
3614 	{
3615 	    rettv->v_type = VAR_NUMBER;
3616 	    rettv->vval.v_number = result;
3617 	}
3618     }
3619 
3620     return OK;
3621 }
3622 
3623 /*
3624  * Handle second level expression:
3625  *	expr3 && expr3 && expr3	    logical AND
3626  *
3627  * "arg" must point to the first non-white of the expression.
3628  * "arg" is advanced to the next non-white after the recognized expression.
3629  *
3630  * Return OK or FAIL.
3631  */
3632     static int
3633 eval3(char_u **arg, typval_T *rettv, int evaluate)
3634 {
3635     typval_T	var2;
3636     long	result;
3637     int		first;
3638     int		error = FALSE;
3639 
3640     /*
3641      * Get the first variable.
3642      */
3643     if (eval4(arg, rettv, evaluate) == FAIL)
3644 	return FAIL;
3645 
3646     /*
3647      * Repeat until there is no following "&&".
3648      */
3649     first = TRUE;
3650     result = TRUE;
3651     while ((*arg)[0] == '&' && (*arg)[1] == '&')
3652     {
3653 	if (evaluate && first)
3654 	{
3655 	    if (tv_get_number_chk(rettv, &error) == 0)
3656 		result = FALSE;
3657 	    clear_tv(rettv);
3658 	    if (error)
3659 		return FAIL;
3660 	    first = FALSE;
3661 	}
3662 
3663 	/*
3664 	 * Get the second variable.
3665 	 */
3666 	*arg = skipwhite(*arg + 2);
3667 	if (eval4(arg, &var2, evaluate && result) == FAIL)
3668 	    return FAIL;
3669 
3670 	/*
3671 	 * Compute the result.
3672 	 */
3673 	if (evaluate && result)
3674 	{
3675 	    if (tv_get_number_chk(&var2, &error) == 0)
3676 		result = FALSE;
3677 	    clear_tv(&var2);
3678 	    if (error)
3679 		return FAIL;
3680 	}
3681 	if (evaluate)
3682 	{
3683 	    rettv->v_type = VAR_NUMBER;
3684 	    rettv->vval.v_number = result;
3685 	}
3686     }
3687 
3688     return OK;
3689 }
3690 
3691 /*
3692  * Handle third level expression:
3693  *	var1 == var2
3694  *	var1 =~ var2
3695  *	var1 != var2
3696  *	var1 !~ var2
3697  *	var1 > var2
3698  *	var1 >= var2
3699  *	var1 < var2
3700  *	var1 <= var2
3701  *	var1 is var2
3702  *	var1 isnot var2
3703  *
3704  * "arg" must point to the first non-white of the expression.
3705  * "arg" is advanced to the next non-white after the recognized expression.
3706  *
3707  * Return OK or FAIL.
3708  */
3709     static int
3710 eval4(char_u **arg, typval_T *rettv, int evaluate)
3711 {
3712     typval_T	var2;
3713     char_u	*p;
3714     int		i;
3715     exptype_T	type = TYPE_UNKNOWN;
3716     int		type_is = FALSE;    /* TRUE for "is" and "isnot" */
3717     int		len = 2;
3718     int		ic;
3719 
3720     /*
3721      * Get the first variable.
3722      */
3723     if (eval5(arg, rettv, evaluate) == FAIL)
3724 	return FAIL;
3725 
3726     p = *arg;
3727     switch (p[0])
3728     {
3729 	case '=':   if (p[1] == '=')
3730 			type = TYPE_EQUAL;
3731 		    else if (p[1] == '~')
3732 			type = TYPE_MATCH;
3733 		    break;
3734 	case '!':   if (p[1] == '=')
3735 			type = TYPE_NEQUAL;
3736 		    else if (p[1] == '~')
3737 			type = TYPE_NOMATCH;
3738 		    break;
3739 	case '>':   if (p[1] != '=')
3740 		    {
3741 			type = TYPE_GREATER;
3742 			len = 1;
3743 		    }
3744 		    else
3745 			type = TYPE_GEQUAL;
3746 		    break;
3747 	case '<':   if (p[1] != '=')
3748 		    {
3749 			type = TYPE_SMALLER;
3750 			len = 1;
3751 		    }
3752 		    else
3753 			type = TYPE_SEQUAL;
3754 		    break;
3755 	case 'i':   if (p[1] == 's')
3756 		    {
3757 			if (p[2] == 'n' && p[3] == 'o' && p[4] == 't')
3758 			    len = 5;
3759 			i = p[len];
3760 			if (!isalnum(i) && i != '_')
3761 			{
3762 			    type = len == 2 ? TYPE_EQUAL : TYPE_NEQUAL;
3763 			    type_is = TRUE;
3764 			}
3765 		    }
3766 		    break;
3767     }
3768 
3769     /*
3770      * If there is a comparative operator, use it.
3771      */
3772     if (type != TYPE_UNKNOWN)
3773     {
3774 	/* extra question mark appended: ignore case */
3775 	if (p[len] == '?')
3776 	{
3777 	    ic = TRUE;
3778 	    ++len;
3779 	}
3780 	/* extra '#' appended: match case */
3781 	else if (p[len] == '#')
3782 	{
3783 	    ic = FALSE;
3784 	    ++len;
3785 	}
3786 	/* nothing appended: use 'ignorecase' */
3787 	else
3788 	    ic = p_ic;
3789 
3790 	/*
3791 	 * Get the second variable.
3792 	 */
3793 	*arg = skipwhite(p + len);
3794 	if (eval5(arg, &var2, evaluate) == FAIL)
3795 	{
3796 	    clear_tv(rettv);
3797 	    return FAIL;
3798 	}
3799 	if (evaluate)
3800 	{
3801 	    int ret = typval_compare(rettv, &var2, type, type_is, ic);
3802 
3803 	    clear_tv(&var2);
3804 	    return ret;
3805 	}
3806     }
3807 
3808     return OK;
3809 }
3810 
3811 /*
3812  * Handle fourth level expression:
3813  *	+	number addition
3814  *	-	number subtraction
3815  *	.	string concatenation
3816  *
3817  * "arg" must point to the first non-white of the expression.
3818  * "arg" is advanced to the next non-white after the recognized expression.
3819  *
3820  * Return OK or FAIL.
3821  */
3822     static int
3823 eval5(char_u **arg, typval_T *rettv, int evaluate)
3824 {
3825     typval_T	var2;
3826     typval_T	var3;
3827     int		op;
3828     varnumber_T	n1, n2;
3829 #ifdef FEAT_FLOAT
3830     float_T	f1 = 0, f2 = 0;
3831 #endif
3832     char_u	*s1, *s2;
3833     char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
3834     char_u	*p;
3835 
3836     /*
3837      * Get the first variable.
3838      */
3839     if (eval6(arg, rettv, evaluate, FALSE) == FAIL)
3840 	return FAIL;
3841 
3842     /*
3843      * Repeat computing, until no '+', '-' or '.' is following.
3844      */
3845     for (;;)
3846     {
3847 	op = **arg;
3848 	if (op != '+' && op != '-' && op != '.')
3849 	    break;
3850 
3851 	if ((op != '+' || (rettv->v_type != VAR_LIST
3852 						 && rettv->v_type != VAR_BLOB))
3853 #ifdef FEAT_FLOAT
3854 		&& (op == '.' || rettv->v_type != VAR_FLOAT)
3855 #endif
3856 		)
3857 	{
3858 	    /* For "list + ...", an illegal use of the first operand as
3859 	     * a number cannot be determined before evaluating the 2nd
3860 	     * operand: if this is also a list, all is ok.
3861 	     * For "something . ...", "something - ..." or "non-list + ...",
3862 	     * we know that the first operand needs to be a string or number
3863 	     * without evaluating the 2nd operand.  So check before to avoid
3864 	     * side effects after an error. */
3865 	    if (evaluate && tv_get_string_chk(rettv) == NULL)
3866 	    {
3867 		clear_tv(rettv);
3868 		return FAIL;
3869 	    }
3870 	}
3871 
3872 	/*
3873 	 * Get the second variable.
3874 	 */
3875 	*arg = skipwhite(*arg + 1);
3876 	if (eval6(arg, &var2, evaluate, op == '.') == FAIL)
3877 	{
3878 	    clear_tv(rettv);
3879 	    return FAIL;
3880 	}
3881 
3882 	if (evaluate)
3883 	{
3884 	    /*
3885 	     * Compute the result.
3886 	     */
3887 	    if (op == '.')
3888 	    {
3889 		s1 = tv_get_string_buf(rettv, buf1);	/* already checked */
3890 		s2 = tv_get_string_buf_chk(&var2, buf2);
3891 		if (s2 == NULL)		/* type error ? */
3892 		{
3893 		    clear_tv(rettv);
3894 		    clear_tv(&var2);
3895 		    return FAIL;
3896 		}
3897 		p = concat_str(s1, s2);
3898 		clear_tv(rettv);
3899 		rettv->v_type = VAR_STRING;
3900 		rettv->vval.v_string = p;
3901 	    }
3902 	    else if (op == '+' && rettv->v_type == VAR_BLOB
3903 						   && var2.v_type == VAR_BLOB)
3904 	    {
3905 		blob_T  *b1 = rettv->vval.v_blob;
3906 		blob_T  *b2 = var2.vval.v_blob;
3907 		blob_T	*b = blob_alloc();
3908 		int	i;
3909 
3910 		if (b != NULL)
3911 		{
3912 		    for (i = 0; i < blob_len(b1); i++)
3913 			ga_append(&b->bv_ga, blob_get(b1, i));
3914 		    for (i = 0; i < blob_len(b2); i++)
3915 			ga_append(&b->bv_ga, blob_get(b2, i));
3916 
3917 		    clear_tv(rettv);
3918 		    rettv_blob_set(rettv, b);
3919 		}
3920 	    }
3921 	    else if (op == '+' && rettv->v_type == VAR_LIST
3922 						   && var2.v_type == VAR_LIST)
3923 	    {
3924 		/* concatenate Lists */
3925 		if (list_concat(rettv->vval.v_list, var2.vval.v_list,
3926 							       &var3) == FAIL)
3927 		{
3928 		    clear_tv(rettv);
3929 		    clear_tv(&var2);
3930 		    return FAIL;
3931 		}
3932 		clear_tv(rettv);
3933 		*rettv = var3;
3934 	    }
3935 	    else
3936 	    {
3937 		int	    error = FALSE;
3938 
3939 #ifdef FEAT_FLOAT
3940 		if (rettv->v_type == VAR_FLOAT)
3941 		{
3942 		    f1 = rettv->vval.v_float;
3943 		    n1 = 0;
3944 		}
3945 		else
3946 #endif
3947 		{
3948 		    n1 = tv_get_number_chk(rettv, &error);
3949 		    if (error)
3950 		    {
3951 			/* This can only happen for "list + non-list".  For
3952 			 * "non-list + ..." or "something - ...", we returned
3953 			 * before evaluating the 2nd operand. */
3954 			clear_tv(rettv);
3955 			return FAIL;
3956 		    }
3957 #ifdef FEAT_FLOAT
3958 		    if (var2.v_type == VAR_FLOAT)
3959 			f1 = n1;
3960 #endif
3961 		}
3962 #ifdef FEAT_FLOAT
3963 		if (var2.v_type == VAR_FLOAT)
3964 		{
3965 		    f2 = var2.vval.v_float;
3966 		    n2 = 0;
3967 		}
3968 		else
3969 #endif
3970 		{
3971 		    n2 = tv_get_number_chk(&var2, &error);
3972 		    if (error)
3973 		    {
3974 			clear_tv(rettv);
3975 			clear_tv(&var2);
3976 			return FAIL;
3977 		    }
3978 #ifdef FEAT_FLOAT
3979 		    if (rettv->v_type == VAR_FLOAT)
3980 			f2 = n2;
3981 #endif
3982 		}
3983 		clear_tv(rettv);
3984 
3985 #ifdef FEAT_FLOAT
3986 		/* If there is a float on either side the result is a float. */
3987 		if (rettv->v_type == VAR_FLOAT || var2.v_type == VAR_FLOAT)
3988 		{
3989 		    if (op == '+')
3990 			f1 = f1 + f2;
3991 		    else
3992 			f1 = f1 - f2;
3993 		    rettv->v_type = VAR_FLOAT;
3994 		    rettv->vval.v_float = f1;
3995 		}
3996 		else
3997 #endif
3998 		{
3999 		    if (op == '+')
4000 			n1 = n1 + n2;
4001 		    else
4002 			n1 = n1 - n2;
4003 		    rettv->v_type = VAR_NUMBER;
4004 		    rettv->vval.v_number = n1;
4005 		}
4006 	    }
4007 	    clear_tv(&var2);
4008 	}
4009     }
4010     return OK;
4011 }
4012 
4013 /*
4014  * Handle fifth level expression:
4015  *	*	number multiplication
4016  *	/	number division
4017  *	%	number modulo
4018  *
4019  * "arg" must point to the first non-white of the expression.
4020  * "arg" is advanced to the next non-white after the recognized expression.
4021  *
4022  * Return OK or FAIL.
4023  */
4024     static int
4025 eval6(
4026     char_u	**arg,
4027     typval_T	*rettv,
4028     int		evaluate,
4029     int		want_string)  /* after "." operator */
4030 {
4031     typval_T	var2;
4032     int		op;
4033     varnumber_T	n1, n2;
4034 #ifdef FEAT_FLOAT
4035     int		use_float = FALSE;
4036     float_T	f1 = 0, f2;
4037 #endif
4038     int		error = FALSE;
4039 
4040     /*
4041      * Get the first variable.
4042      */
4043     if (eval7(arg, rettv, evaluate, want_string) == FAIL)
4044 	return FAIL;
4045 
4046     /*
4047      * Repeat computing, until no '*', '/' or '%' is following.
4048      */
4049     for (;;)
4050     {
4051 	op = **arg;
4052 	if (op != '*' && op != '/' && op != '%')
4053 	    break;
4054 
4055 	if (evaluate)
4056 	{
4057 #ifdef FEAT_FLOAT
4058 	    if (rettv->v_type == VAR_FLOAT)
4059 	    {
4060 		f1 = rettv->vval.v_float;
4061 		use_float = TRUE;
4062 		n1 = 0;
4063 	    }
4064 	    else
4065 #endif
4066 		n1 = tv_get_number_chk(rettv, &error);
4067 	    clear_tv(rettv);
4068 	    if (error)
4069 		return FAIL;
4070 	}
4071 	else
4072 	    n1 = 0;
4073 
4074 	/*
4075 	 * Get the second variable.
4076 	 */
4077 	*arg = skipwhite(*arg + 1);
4078 	if (eval7(arg, &var2, evaluate, FALSE) == FAIL)
4079 	    return FAIL;
4080 
4081 	if (evaluate)
4082 	{
4083 #ifdef FEAT_FLOAT
4084 	    if (var2.v_type == VAR_FLOAT)
4085 	    {
4086 		if (!use_float)
4087 		{
4088 		    f1 = n1;
4089 		    use_float = TRUE;
4090 		}
4091 		f2 = var2.vval.v_float;
4092 		n2 = 0;
4093 	    }
4094 	    else
4095 #endif
4096 	    {
4097 		n2 = tv_get_number_chk(&var2, &error);
4098 		clear_tv(&var2);
4099 		if (error)
4100 		    return FAIL;
4101 #ifdef FEAT_FLOAT
4102 		if (use_float)
4103 		    f2 = n2;
4104 #endif
4105 	    }
4106 
4107 	    /*
4108 	     * Compute the result.
4109 	     * When either side is a float the result is a float.
4110 	     */
4111 #ifdef FEAT_FLOAT
4112 	    if (use_float)
4113 	    {
4114 		if (op == '*')
4115 		    f1 = f1 * f2;
4116 		else if (op == '/')
4117 		{
4118 # ifdef VMS
4119 		    /* VMS crashes on divide by zero, work around it */
4120 		    if (f2 == 0.0)
4121 		    {
4122 			if (f1 == 0)
4123 			    f1 = -1 * __F_FLT_MAX - 1L;   /* similar to NaN */
4124 			else if (f1 < 0)
4125 			    f1 = -1 * __F_FLT_MAX;
4126 			else
4127 			    f1 = __F_FLT_MAX;
4128 		    }
4129 		    else
4130 			f1 = f1 / f2;
4131 # else
4132 		    /* We rely on the floating point library to handle divide
4133 		     * by zero to result in "inf" and not a crash. */
4134 		    f1 = f1 / f2;
4135 # endif
4136 		}
4137 		else
4138 		{
4139 		    emsg(_("E804: Cannot use '%' with Float"));
4140 		    return FAIL;
4141 		}
4142 		rettv->v_type = VAR_FLOAT;
4143 		rettv->vval.v_float = f1;
4144 	    }
4145 	    else
4146 #endif
4147 	    {
4148 		if (op == '*')
4149 		    n1 = n1 * n2;
4150 		else if (op == '/')
4151 		    n1 = num_divide(n1, n2);
4152 		else
4153 		    n1 = num_modulus(n1, n2);
4154 
4155 		rettv->v_type = VAR_NUMBER;
4156 		rettv->vval.v_number = n1;
4157 	    }
4158 	}
4159     }
4160 
4161     return OK;
4162 }
4163 
4164 /*
4165  * Handle sixth level expression:
4166  *  number		number constant
4167  *  0zFFFFFFFF		Blob constant
4168  *  "string"		string constant
4169  *  'string'		literal string constant
4170  *  &option-name	option value
4171  *  @r			register contents
4172  *  identifier		variable value
4173  *  function()		function call
4174  *  $VAR		environment variable
4175  *  (expression)	nested expression
4176  *  [expr, expr]	List
4177  *  {key: val, key: val}  Dictionary
4178  *
4179  *  Also handle:
4180  *  ! in front		logical NOT
4181  *  - in front		unary minus
4182  *  + in front		unary plus (ignored)
4183  *  trailing []		subscript in String or List
4184  *  trailing .name	entry in Dictionary
4185  *
4186  * "arg" must point to the first non-white of the expression.
4187  * "arg" is advanced to the next non-white after the recognized expression.
4188  *
4189  * Return OK or FAIL.
4190  */
4191     static int
4192 eval7(
4193     char_u	**arg,
4194     typval_T	*rettv,
4195     int		evaluate,
4196     int		want_string UNUSED)	/* after "." operator */
4197 {
4198     varnumber_T	n;
4199     int		len;
4200     char_u	*s;
4201     char_u	*start_leader, *end_leader;
4202     int		ret = OK;
4203     char_u	*alias;
4204 
4205     /*
4206      * Initialise variable so that clear_tv() can't mistake this for a
4207      * string and free a string that isn't there.
4208      */
4209     rettv->v_type = VAR_UNKNOWN;
4210 
4211     /*
4212      * Skip '!', '-' and '+' characters.  They are handled later.
4213      */
4214     start_leader = *arg;
4215     while (**arg == '!' || **arg == '-' || **arg == '+')
4216 	*arg = skipwhite(*arg + 1);
4217     end_leader = *arg;
4218 
4219     switch (**arg)
4220     {
4221     /*
4222      * Number constant.
4223      */
4224     case '0':
4225     case '1':
4226     case '2':
4227     case '3':
4228     case '4':
4229     case '5':
4230     case '6':
4231     case '7':
4232     case '8':
4233     case '9':
4234 	{
4235 #ifdef FEAT_FLOAT
4236 		char_u *p = skipdigits(*arg + 1);
4237 		int    get_float = FALSE;
4238 
4239 		/* We accept a float when the format matches
4240 		 * "[0-9]\+\.[0-9]\+\([eE][+-]\?[0-9]\+\)\?".  This is very
4241 		 * strict to avoid backwards compatibility problems.
4242 		 * Don't look for a float after the "." operator, so that
4243 		 * ":let vers = 1.2.3" doesn't fail. */
4244 		if (!want_string && p[0] == '.' && vim_isdigit(p[1]))
4245 		{
4246 		    get_float = TRUE;
4247 		    p = skipdigits(p + 2);
4248 		    if (*p == 'e' || *p == 'E')
4249 		    {
4250 			++p;
4251 			if (*p == '-' || *p == '+')
4252 			    ++p;
4253 			if (!vim_isdigit(*p))
4254 			    get_float = FALSE;
4255 			else
4256 			    p = skipdigits(p + 1);
4257 		    }
4258 		    if (ASCII_ISALPHA(*p) || *p == '.')
4259 			get_float = FALSE;
4260 		}
4261 		if (get_float)
4262 		{
4263 		    float_T	f;
4264 
4265 		    *arg += string2float(*arg, &f);
4266 		    if (evaluate)
4267 		    {
4268 			rettv->v_type = VAR_FLOAT;
4269 			rettv->vval.v_float = f;
4270 		    }
4271 		}
4272 		else
4273 #endif
4274 		if (**arg == '0' && ((*arg)[1] == 'z' || (*arg)[1] == 'Z'))
4275 		{
4276 		    char_u  *bp;
4277 		    blob_T  *blob = NULL;  // init for gcc
4278 
4279 		    // Blob constant: 0z0123456789abcdef
4280 		    if (evaluate)
4281 			blob = blob_alloc();
4282 		    for (bp = *arg + 2; vim_isxdigit(bp[0]); bp += 2)
4283 		    {
4284 			if (!vim_isxdigit(bp[1]))
4285 			{
4286 			    if (blob != NULL)
4287 			    {
4288 				emsg(_("E973: Blob literal should have an even number of hex characters"));
4289 				ga_clear(&blob->bv_ga);
4290 				VIM_CLEAR(blob);
4291 			    }
4292 			    ret = FAIL;
4293 			    break;
4294 			}
4295 			if (blob != NULL)
4296 			    ga_append(&blob->bv_ga,
4297 					 (hex2nr(*bp) << 4) + hex2nr(*(bp+1)));
4298 			if (bp[2] == '.' && vim_isxdigit(bp[3]))
4299 			    ++bp;
4300 		    }
4301 		    if (blob != NULL)
4302 			rettv_blob_set(rettv, blob);
4303 		    *arg = bp;
4304 		}
4305 		else
4306 		{
4307 		    // decimal, hex or octal number
4308 		    vim_str2nr(*arg, NULL, &len, STR2NR_ALL, &n, NULL, 0);
4309 		    *arg += len;
4310 		    if (evaluate)
4311 		    {
4312 			rettv->v_type = VAR_NUMBER;
4313 			rettv->vval.v_number = n;
4314 		    }
4315 		}
4316 		break;
4317 	}
4318 
4319     /*
4320      * String constant: "string".
4321      */
4322     case '"':	ret = get_string_tv(arg, rettv, evaluate);
4323 		break;
4324 
4325     /*
4326      * Literal string constant: 'str''ing'.
4327      */
4328     case '\'':	ret = get_lit_string_tv(arg, rettv, evaluate);
4329 		break;
4330 
4331     /*
4332      * List: [expr, expr]
4333      */
4334     case '[':	ret = get_list_tv(arg, rettv, evaluate);
4335 		break;
4336 
4337     /*
4338      * Lambda: {arg, arg -> expr}
4339      * Dictionary: {key: val, key: val}
4340      */
4341     case '{':	ret = get_lambda_tv(arg, rettv, evaluate);
4342 		if (ret == NOTDONE)
4343 		    ret = dict_get_tv(arg, rettv, evaluate);
4344 		break;
4345 
4346     /*
4347      * Option value: &name
4348      */
4349     case '&':	ret = get_option_tv(arg, rettv, evaluate);
4350 		break;
4351 
4352     /*
4353      * Environment variable: $VAR.
4354      */
4355     case '$':	ret = get_env_tv(arg, rettv, evaluate);
4356 		break;
4357 
4358     /*
4359      * Register contents: @r.
4360      */
4361     case '@':	++*arg;
4362 		if (evaluate)
4363 		{
4364 		    rettv->v_type = VAR_STRING;
4365 		    rettv->vval.v_string = get_reg_contents(**arg,
4366 							    GREG_EXPR_SRC);
4367 		}
4368 		if (**arg != NUL)
4369 		    ++*arg;
4370 		break;
4371 
4372     /*
4373      * nested expression: (expression).
4374      */
4375     case '(':	*arg = skipwhite(*arg + 1);
4376 		ret = eval1(arg, rettv, evaluate);	/* recursive! */
4377 		if (**arg == ')')
4378 		    ++*arg;
4379 		else if (ret == OK)
4380 		{
4381 		    emsg(_("E110: Missing ')'"));
4382 		    clear_tv(rettv);
4383 		    ret = FAIL;
4384 		}
4385 		break;
4386 
4387     default:	ret = NOTDONE;
4388 		break;
4389     }
4390 
4391     if (ret == NOTDONE)
4392     {
4393 	/*
4394 	 * Must be a variable or function name.
4395 	 * Can also be a curly-braces kind of name: {expr}.
4396 	 */
4397 	s = *arg;
4398 	len = get_name_len(arg, &alias, evaluate, TRUE);
4399 	if (alias != NULL)
4400 	    s = alias;
4401 
4402 	if (len <= 0)
4403 	    ret = FAIL;
4404 	else
4405 	{
4406 	    if (**arg == '(')		/* recursive! */
4407 	    {
4408 		partial_T *partial;
4409 
4410 		if (!evaluate)
4411 		    check_vars(s, len);
4412 
4413 		/* If "s" is the name of a variable of type VAR_FUNC
4414 		 * use its contents. */
4415 		s = deref_func_name(s, &len, &partial, !evaluate);
4416 
4417 		/* Need to make a copy, in case evaluating the arguments makes
4418 		 * the name invalid. */
4419 		s = vim_strsave(s);
4420 		if (s == NULL)
4421 		    ret = FAIL;
4422 		else
4423 		    /* Invoke the function. */
4424 		    ret = get_func_tv(s, len, rettv, arg,
4425 			      curwin->w_cursor.lnum, curwin->w_cursor.lnum,
4426 			      &len, evaluate, partial, NULL);
4427 		vim_free(s);
4428 
4429 		/* If evaluate is FALSE rettv->v_type was not set in
4430 		 * get_func_tv, but it's needed in handle_subscript() to parse
4431 		 * what follows. So set it here. */
4432 		if (rettv->v_type == VAR_UNKNOWN && !evaluate && **arg == '(')
4433 		{
4434 		    rettv->vval.v_string = NULL;
4435 		    rettv->v_type = VAR_FUNC;
4436 		}
4437 
4438 		/* Stop the expression evaluation when immediately
4439 		 * aborting on error, or when an interrupt occurred or
4440 		 * an exception was thrown but not caught. */
4441 		if (aborting())
4442 		{
4443 		    if (ret == OK)
4444 			clear_tv(rettv);
4445 		    ret = FAIL;
4446 		}
4447 	    }
4448 	    else if (evaluate)
4449 		ret = get_var_tv(s, len, rettv, NULL, TRUE, FALSE);
4450 	    else
4451 	    {
4452 		check_vars(s, len);
4453 		ret = OK;
4454 	    }
4455 	}
4456 	vim_free(alias);
4457     }
4458 
4459     *arg = skipwhite(*arg);
4460 
4461     /* Handle following '[', '(' and '.' for expr[expr], expr.name,
4462      * expr(expr). */
4463     if (ret == OK)
4464 	ret = handle_subscript(arg, rettv, evaluate, TRUE);
4465 
4466     /*
4467      * Apply logical NOT and unary '-', from right to left, ignore '+'.
4468      */
4469     if (ret == OK && evaluate && end_leader > start_leader)
4470     {
4471 	int	    error = FALSE;
4472 	varnumber_T val = 0;
4473 #ifdef FEAT_FLOAT
4474 	float_T	    f = 0.0;
4475 
4476 	if (rettv->v_type == VAR_FLOAT)
4477 	    f = rettv->vval.v_float;
4478 	else
4479 #endif
4480 	    val = tv_get_number_chk(rettv, &error);
4481 	if (error)
4482 	{
4483 	    clear_tv(rettv);
4484 	    ret = FAIL;
4485 	}
4486 	else
4487 	{
4488 	    while (end_leader > start_leader)
4489 	    {
4490 		--end_leader;
4491 		if (*end_leader == '!')
4492 		{
4493 #ifdef FEAT_FLOAT
4494 		    if (rettv->v_type == VAR_FLOAT)
4495 			f = !f;
4496 		    else
4497 #endif
4498 			val = !val;
4499 		}
4500 		else if (*end_leader == '-')
4501 		{
4502 #ifdef FEAT_FLOAT
4503 		    if (rettv->v_type == VAR_FLOAT)
4504 			f = -f;
4505 		    else
4506 #endif
4507 			val = -val;
4508 		}
4509 	    }
4510 #ifdef FEAT_FLOAT
4511 	    if (rettv->v_type == VAR_FLOAT)
4512 	    {
4513 		clear_tv(rettv);
4514 		rettv->vval.v_float = f;
4515 	    }
4516 	    else
4517 #endif
4518 	    {
4519 		clear_tv(rettv);
4520 		rettv->v_type = VAR_NUMBER;
4521 		rettv->vval.v_number = val;
4522 	    }
4523 	}
4524     }
4525 
4526     return ret;
4527 }
4528 
4529 /*
4530  * Evaluate an "[expr]" or "[expr:expr]" index.  Also "dict.key".
4531  * "*arg" points to the '[' or '.'.
4532  * Returns FAIL or OK. "*arg" is advanced to after the ']'.
4533  */
4534     static int
4535 eval_index(
4536     char_u	**arg,
4537     typval_T	*rettv,
4538     int		evaluate,
4539     int		verbose)	/* give error messages */
4540 {
4541     int		empty1 = FALSE, empty2 = FALSE;
4542     typval_T	var1, var2;
4543     long	i;
4544     long	n1, n2 = 0;
4545     long	len = -1;
4546     int		range = FALSE;
4547     char_u	*s;
4548     char_u	*key = NULL;
4549 
4550     switch (rettv->v_type)
4551     {
4552 	case VAR_FUNC:
4553 	case VAR_PARTIAL:
4554 	    if (verbose)
4555 		emsg(_("E695: Cannot index a Funcref"));
4556 	    return FAIL;
4557 	case VAR_FLOAT:
4558 #ifdef FEAT_FLOAT
4559 	    if (verbose)
4560 		emsg(_(e_float_as_string));
4561 	    return FAIL;
4562 #endif
4563 	case VAR_SPECIAL:
4564 	case VAR_JOB:
4565 	case VAR_CHANNEL:
4566 	    if (verbose)
4567 		emsg(_("E909: Cannot index a special variable"));
4568 	    return FAIL;
4569 	case VAR_UNKNOWN:
4570 	    if (evaluate)
4571 		return FAIL;
4572 	    /* FALLTHROUGH */
4573 
4574 	case VAR_STRING:
4575 	case VAR_NUMBER:
4576 	case VAR_LIST:
4577 	case VAR_DICT:
4578 	case VAR_BLOB:
4579 	    break;
4580     }
4581 
4582     init_tv(&var1);
4583     init_tv(&var2);
4584     if (**arg == '.')
4585     {
4586 	/*
4587 	 * dict.name
4588 	 */
4589 	key = *arg + 1;
4590 	for (len = 0; ASCII_ISALNUM(key[len]) || key[len] == '_'; ++len)
4591 	    ;
4592 	if (len == 0)
4593 	    return FAIL;
4594 	*arg = skipwhite(key + len);
4595     }
4596     else
4597     {
4598 	/*
4599 	 * something[idx]
4600 	 *
4601 	 * Get the (first) variable from inside the [].
4602 	 */
4603 	*arg = skipwhite(*arg + 1);
4604 	if (**arg == ':')
4605 	    empty1 = TRUE;
4606 	else if (eval1(arg, &var1, evaluate) == FAIL)	/* recursive! */
4607 	    return FAIL;
4608 	else if (evaluate && tv_get_string_chk(&var1) == NULL)
4609 	{
4610 	    /* not a number or string */
4611 	    clear_tv(&var1);
4612 	    return FAIL;
4613 	}
4614 
4615 	/*
4616 	 * Get the second variable from inside the [:].
4617 	 */
4618 	if (**arg == ':')
4619 	{
4620 	    range = TRUE;
4621 	    *arg = skipwhite(*arg + 1);
4622 	    if (**arg == ']')
4623 		empty2 = TRUE;
4624 	    else if (eval1(arg, &var2, evaluate) == FAIL)	/* recursive! */
4625 	    {
4626 		if (!empty1)
4627 		    clear_tv(&var1);
4628 		return FAIL;
4629 	    }
4630 	    else if (evaluate && tv_get_string_chk(&var2) == NULL)
4631 	    {
4632 		/* not a number or string */
4633 		if (!empty1)
4634 		    clear_tv(&var1);
4635 		clear_tv(&var2);
4636 		return FAIL;
4637 	    }
4638 	}
4639 
4640 	/* Check for the ']'. */
4641 	if (**arg != ']')
4642 	{
4643 	    if (verbose)
4644 		emsg(_(e_missbrac));
4645 	    clear_tv(&var1);
4646 	    if (range)
4647 		clear_tv(&var2);
4648 	    return FAIL;
4649 	}
4650 	*arg = skipwhite(*arg + 1);	/* skip the ']' */
4651     }
4652 
4653     if (evaluate)
4654     {
4655 	n1 = 0;
4656 	if (!empty1 && rettv->v_type != VAR_DICT)
4657 	{
4658 	    n1 = tv_get_number(&var1);
4659 	    clear_tv(&var1);
4660 	}
4661 	if (range)
4662 	{
4663 	    if (empty2)
4664 		n2 = -1;
4665 	    else
4666 	    {
4667 		n2 = tv_get_number(&var2);
4668 		clear_tv(&var2);
4669 	    }
4670 	}
4671 
4672 	switch (rettv->v_type)
4673 	{
4674 	    case VAR_UNKNOWN:
4675 	    case VAR_FUNC:
4676 	    case VAR_PARTIAL:
4677 	    case VAR_FLOAT:
4678 	    case VAR_SPECIAL:
4679 	    case VAR_JOB:
4680 	    case VAR_CHANNEL:
4681 		break; /* not evaluating, skipping over subscript */
4682 
4683 	    case VAR_NUMBER:
4684 	    case VAR_STRING:
4685 		s = tv_get_string(rettv);
4686 		len = (long)STRLEN(s);
4687 		if (range)
4688 		{
4689 		    /* The resulting variable is a substring.  If the indexes
4690 		     * are out of range the result is empty. */
4691 		    if (n1 < 0)
4692 		    {
4693 			n1 = len + n1;
4694 			if (n1 < 0)
4695 			    n1 = 0;
4696 		    }
4697 		    if (n2 < 0)
4698 			n2 = len + n2;
4699 		    else if (n2 >= len)
4700 			n2 = len;
4701 		    if (n1 >= len || n2 < 0 || n1 > n2)
4702 			s = NULL;
4703 		    else
4704 			s = vim_strnsave(s + n1, (int)(n2 - n1 + 1));
4705 		}
4706 		else
4707 		{
4708 		    /* The resulting variable is a string of a single
4709 		     * character.  If the index is too big or negative the
4710 		     * result is empty. */
4711 		    if (n1 >= len || n1 < 0)
4712 			s = NULL;
4713 		    else
4714 			s = vim_strnsave(s + n1, 1);
4715 		}
4716 		clear_tv(rettv);
4717 		rettv->v_type = VAR_STRING;
4718 		rettv->vval.v_string = s;
4719 		break;
4720 
4721 	    case VAR_BLOB:
4722 		len = blob_len(rettv->vval.v_blob);
4723 		if (range)
4724 		{
4725 		    // The resulting variable is a sub-blob.  If the indexes
4726 		    // are out of range the result is empty.
4727 		    if (n1 < 0)
4728 		    {
4729 			n1 = len + n1;
4730 			if (n1 < 0)
4731 			    n1 = 0;
4732 		    }
4733 		    if (n2 < 0)
4734 			n2 = len + n2;
4735 		    else if (n2 >= len)
4736 			n2 = len - 1;
4737 		    if (n1 >= len || n2 < 0 || n1 > n2)
4738 		    {
4739 			clear_tv(rettv);
4740 			rettv->v_type = VAR_BLOB;
4741 			rettv->vval.v_blob = NULL;
4742 		    }
4743 		    else
4744 		    {
4745 			blob_T  *blob = blob_alloc();
4746 
4747 			if (blob != NULL)
4748 			{
4749 			    if (ga_grow(&blob->bv_ga, n2 - n1 + 1) == FAIL)
4750 			    {
4751 				blob_free(blob);
4752 				return FAIL;
4753 			    }
4754 			    blob->bv_ga.ga_len = n2 - n1 + 1;
4755 			    for (i = n1; i <= n2; i++)
4756 				blob_set(blob, i - n1,
4757 					      blob_get(rettv->vval.v_blob, i));
4758 
4759 			    clear_tv(rettv);
4760 			    rettv_blob_set(rettv, blob);
4761 			}
4762 		    }
4763 		}
4764 		else
4765 		{
4766 		    // The resulting variable is a byte value.
4767 		    // If the index is too big or negative that is an error.
4768 		    if (n1 < 0)
4769 			n1 = len + n1;
4770 		    if (n1 < len && n1 >= 0)
4771 		    {
4772 			int v = blob_get(rettv->vval.v_blob, n1);
4773 
4774 			clear_tv(rettv);
4775 			rettv->v_type = VAR_NUMBER;
4776 			rettv->vval.v_number = v;
4777 		    }
4778 		    else
4779 			semsg(_(e_blobidx), n1);
4780 		}
4781 		break;
4782 
4783 	    case VAR_LIST:
4784 		len = list_len(rettv->vval.v_list);
4785 		if (n1 < 0)
4786 		    n1 = len + n1;
4787 		if (!empty1 && (n1 < 0 || n1 >= len))
4788 		{
4789 		    /* For a range we allow invalid values and return an empty
4790 		     * list.  A list index out of range is an error. */
4791 		    if (!range)
4792 		    {
4793 			if (verbose)
4794 			    semsg(_(e_listidx), n1);
4795 			return FAIL;
4796 		    }
4797 		    n1 = len;
4798 		}
4799 		if (range)
4800 		{
4801 		    list_T	*l;
4802 		    listitem_T	*item;
4803 
4804 		    if (n2 < 0)
4805 			n2 = len + n2;
4806 		    else if (n2 >= len)
4807 			n2 = len - 1;
4808 		    if (!empty2 && (n2 < 0 || n2 + 1 < n1))
4809 			n2 = -1;
4810 		    l = list_alloc();
4811 		    if (l == NULL)
4812 			return FAIL;
4813 		    for (item = list_find(rettv->vval.v_list, n1);
4814 							       n1 <= n2; ++n1)
4815 		    {
4816 			if (list_append_tv(l, &item->li_tv) == FAIL)
4817 			{
4818 			    list_free(l);
4819 			    return FAIL;
4820 			}
4821 			item = item->li_next;
4822 		    }
4823 		    clear_tv(rettv);
4824 		    rettv_list_set(rettv, l);
4825 		}
4826 		else
4827 		{
4828 		    copy_tv(&list_find(rettv->vval.v_list, n1)->li_tv, &var1);
4829 		    clear_tv(rettv);
4830 		    *rettv = var1;
4831 		}
4832 		break;
4833 
4834 	    case VAR_DICT:
4835 		if (range)
4836 		{
4837 		    if (verbose)
4838 			emsg(_(e_dictrange));
4839 		    if (len == -1)
4840 			clear_tv(&var1);
4841 		    return FAIL;
4842 		}
4843 		{
4844 		    dictitem_T	*item;
4845 
4846 		    if (len == -1)
4847 		    {
4848 			key = tv_get_string_chk(&var1);
4849 			if (key == NULL)
4850 			{
4851 			    clear_tv(&var1);
4852 			    return FAIL;
4853 			}
4854 		    }
4855 
4856 		    item = dict_find(rettv->vval.v_dict, key, (int)len);
4857 
4858 		    if (item == NULL && verbose)
4859 			semsg(_(e_dictkey), key);
4860 		    if (len == -1)
4861 			clear_tv(&var1);
4862 		    if (item == NULL)
4863 			return FAIL;
4864 
4865 		    copy_tv(&item->di_tv, &var1);
4866 		    clear_tv(rettv);
4867 		    *rettv = var1;
4868 		}
4869 		break;
4870 	}
4871     }
4872 
4873     return OK;
4874 }
4875 
4876 /*
4877  * Get an option value.
4878  * "arg" points to the '&' or '+' before the option name.
4879  * "arg" is advanced to character after the option name.
4880  * Return OK or FAIL.
4881  */
4882     int
4883 get_option_tv(
4884     char_u	**arg,
4885     typval_T	*rettv,	/* when NULL, only check if option exists */
4886     int		evaluate)
4887 {
4888     char_u	*option_end;
4889     long	numval;
4890     char_u	*stringval;
4891     int		opt_type;
4892     int		c;
4893     int		working = (**arg == '+');    /* has("+option") */
4894     int		ret = OK;
4895     int		opt_flags;
4896 
4897     /*
4898      * Isolate the option name and find its value.
4899      */
4900     option_end = find_option_end(arg, &opt_flags);
4901     if (option_end == NULL)
4902     {
4903 	if (rettv != NULL)
4904 	    semsg(_("E112: Option name missing: %s"), *arg);
4905 	return FAIL;
4906     }
4907 
4908     if (!evaluate)
4909     {
4910 	*arg = option_end;
4911 	return OK;
4912     }
4913 
4914     c = *option_end;
4915     *option_end = NUL;
4916     opt_type = get_option_value(*arg, &numval,
4917 			       rettv == NULL ? NULL : &stringval, opt_flags);
4918 
4919     if (opt_type == -3)			/* invalid name */
4920     {
4921 	if (rettv != NULL)
4922 	    semsg(_("E113: Unknown option: %s"), *arg);
4923 	ret = FAIL;
4924     }
4925     else if (rettv != NULL)
4926     {
4927 	if (opt_type == -2)		/* hidden string option */
4928 	{
4929 	    rettv->v_type = VAR_STRING;
4930 	    rettv->vval.v_string = NULL;
4931 	}
4932 	else if (opt_type == -1)	/* hidden number option */
4933 	{
4934 	    rettv->v_type = VAR_NUMBER;
4935 	    rettv->vval.v_number = 0;
4936 	}
4937 	else if (opt_type == 1)		/* number option */
4938 	{
4939 	    rettv->v_type = VAR_NUMBER;
4940 	    rettv->vval.v_number = numval;
4941 	}
4942 	else				/* string option */
4943 	{
4944 	    rettv->v_type = VAR_STRING;
4945 	    rettv->vval.v_string = stringval;
4946 	}
4947     }
4948     else if (working && (opt_type == -2 || opt_type == -1))
4949 	ret = FAIL;
4950 
4951     *option_end = c;		    /* put back for error messages */
4952     *arg = option_end;
4953 
4954     return ret;
4955 }
4956 
4957 /*
4958  * Allocate a variable for a string constant.
4959  * Return OK or FAIL.
4960  */
4961     static int
4962 get_string_tv(char_u **arg, typval_T *rettv, int evaluate)
4963 {
4964     char_u	*p;
4965     char_u	*name;
4966     int		extra = 0;
4967 
4968     /*
4969      * Find the end of the string, skipping backslashed characters.
4970      */
4971     for (p = *arg + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
4972     {
4973 	if (*p == '\\' && p[1] != NUL)
4974 	{
4975 	    ++p;
4976 	    /* A "\<x>" form occupies at least 4 characters, and produces up
4977 	     * to 6 characters: reserve space for 2 extra */
4978 	    if (*p == '<')
4979 		extra += 2;
4980 	}
4981     }
4982 
4983     if (*p != '"')
4984     {
4985 	semsg(_("E114: Missing quote: %s"), *arg);
4986 	return FAIL;
4987     }
4988 
4989     /* If only parsing, set *arg and return here */
4990     if (!evaluate)
4991     {
4992 	*arg = p + 1;
4993 	return OK;
4994     }
4995 
4996     /*
4997      * Copy the string into allocated memory, handling backslashed
4998      * characters.
4999      */
5000     name = alloc((unsigned)(p - *arg + extra));
5001     if (name == NULL)
5002 	return FAIL;
5003     rettv->v_type = VAR_STRING;
5004     rettv->vval.v_string = name;
5005 
5006     for (p = *arg + 1; *p != NUL && *p != '"'; )
5007     {
5008 	if (*p == '\\')
5009 	{
5010 	    switch (*++p)
5011 	    {
5012 		case 'b': *name++ = BS; ++p; break;
5013 		case 'e': *name++ = ESC; ++p; break;
5014 		case 'f': *name++ = FF; ++p; break;
5015 		case 'n': *name++ = NL; ++p; break;
5016 		case 'r': *name++ = CAR; ++p; break;
5017 		case 't': *name++ = TAB; ++p; break;
5018 
5019 		case 'X': /* hex: "\x1", "\x12" */
5020 		case 'x':
5021 		case 'u': /* Unicode: "\u0023" */
5022 		case 'U':
5023 			  if (vim_isxdigit(p[1]))
5024 			  {
5025 			      int	n, nr;
5026 			      int	c = toupper(*p);
5027 
5028 			      if (c == 'X')
5029 				  n = 2;
5030 			      else if (*p == 'u')
5031 				  n = 4;
5032 			      else
5033 				  n = 8;
5034 			      nr = 0;
5035 			      while (--n >= 0 && vim_isxdigit(p[1]))
5036 			      {
5037 				  ++p;
5038 				  nr = (nr << 4) + hex2nr(*p);
5039 			      }
5040 			      ++p;
5041 			      /* For "\u" store the number according to
5042 			       * 'encoding'. */
5043 			      if (c != 'X')
5044 				  name += (*mb_char2bytes)(nr, name);
5045 			      else
5046 				  *name++ = nr;
5047 			  }
5048 			  break;
5049 
5050 			  /* octal: "\1", "\12", "\123" */
5051 		case '0':
5052 		case '1':
5053 		case '2':
5054 		case '3':
5055 		case '4':
5056 		case '5':
5057 		case '6':
5058 		case '7': *name = *p++ - '0';
5059 			  if (*p >= '0' && *p <= '7')
5060 			  {
5061 			      *name = (*name << 3) + *p++ - '0';
5062 			      if (*p >= '0' && *p <= '7')
5063 				  *name = (*name << 3) + *p++ - '0';
5064 			  }
5065 			  ++name;
5066 			  break;
5067 
5068 			    /* Special key, e.g.: "\<C-W>" */
5069 		case '<': extra = trans_special(&p, name, TRUE, TRUE);
5070 			  if (extra != 0)
5071 			  {
5072 			      name += extra;
5073 			      break;
5074 			  }
5075 			  /* FALLTHROUGH */
5076 
5077 		default:  MB_COPY_CHAR(p, name);
5078 			  break;
5079 	    }
5080 	}
5081 	else
5082 	    MB_COPY_CHAR(p, name);
5083 
5084     }
5085     *name = NUL;
5086     if (*p != NUL) /* just in case */
5087 	++p;
5088     *arg = p;
5089 
5090     return OK;
5091 }
5092 
5093 /*
5094  * Allocate a variable for a 'str''ing' constant.
5095  * Return OK or FAIL.
5096  */
5097     static int
5098 get_lit_string_tv(char_u **arg, typval_T *rettv, int evaluate)
5099 {
5100     char_u	*p;
5101     char_u	*str;
5102     int		reduce = 0;
5103 
5104     /*
5105      * Find the end of the string, skipping ''.
5106      */
5107     for (p = *arg + 1; *p != NUL; MB_PTR_ADV(p))
5108     {
5109 	if (*p == '\'')
5110 	{
5111 	    if (p[1] != '\'')
5112 		break;
5113 	    ++reduce;
5114 	    ++p;
5115 	}
5116     }
5117 
5118     if (*p != '\'')
5119     {
5120 	semsg(_("E115: Missing quote: %s"), *arg);
5121 	return FAIL;
5122     }
5123 
5124     /* If only parsing return after setting "*arg" */
5125     if (!evaluate)
5126     {
5127 	*arg = p + 1;
5128 	return OK;
5129     }
5130 
5131     /*
5132      * Copy the string into allocated memory, handling '' to ' reduction.
5133      */
5134     str = alloc((unsigned)((p - *arg) - reduce));
5135     if (str == NULL)
5136 	return FAIL;
5137     rettv->v_type = VAR_STRING;
5138     rettv->vval.v_string = str;
5139 
5140     for (p = *arg + 1; *p != NUL; )
5141     {
5142 	if (*p == '\'')
5143 	{
5144 	    if (p[1] != '\'')
5145 		break;
5146 	    ++p;
5147 	}
5148 	MB_COPY_CHAR(p, str);
5149     }
5150     *str = NUL;
5151     *arg = p + 1;
5152 
5153     return OK;
5154 }
5155 
5156 /*
5157  * Return the function name of the partial.
5158  */
5159     char_u *
5160 partial_name(partial_T *pt)
5161 {
5162     if (pt->pt_name != NULL)
5163 	return pt->pt_name;
5164     return pt->pt_func->uf_name;
5165 }
5166 
5167     static void
5168 partial_free(partial_T *pt)
5169 {
5170     int i;
5171 
5172     for (i = 0; i < pt->pt_argc; ++i)
5173 	clear_tv(&pt->pt_argv[i]);
5174     vim_free(pt->pt_argv);
5175     dict_unref(pt->pt_dict);
5176     if (pt->pt_name != NULL)
5177     {
5178 	func_unref(pt->pt_name);
5179 	vim_free(pt->pt_name);
5180     }
5181     else
5182 	func_ptr_unref(pt->pt_func);
5183     vim_free(pt);
5184 }
5185 
5186 /*
5187  * Unreference a closure: decrement the reference count and free it when it
5188  * becomes zero.
5189  */
5190     void
5191 partial_unref(partial_T *pt)
5192 {
5193     if (pt != NULL && --pt->pt_refcount <= 0)
5194 	partial_free(pt);
5195 }
5196 
5197 static int tv_equal_recurse_limit;
5198 
5199     static int
5200 func_equal(
5201     typval_T *tv1,
5202     typval_T *tv2,
5203     int	     ic)	    /* ignore case */
5204 {
5205     char_u	*s1, *s2;
5206     dict_T	*d1, *d2;
5207     int		a1, a2;
5208     int		i;
5209 
5210     /* empty and NULL function name considered the same */
5211     s1 = tv1->v_type == VAR_FUNC ? tv1->vval.v_string
5212 					   : partial_name(tv1->vval.v_partial);
5213     if (s1 != NULL && *s1 == NUL)
5214 	s1 = NULL;
5215     s2 = tv2->v_type == VAR_FUNC ? tv2->vval.v_string
5216 					   : partial_name(tv2->vval.v_partial);
5217     if (s2 != NULL && *s2 == NUL)
5218 	s2 = NULL;
5219     if (s1 == NULL || s2 == NULL)
5220     {
5221 	if (s1 != s2)
5222 	    return FALSE;
5223     }
5224     else if (STRCMP(s1, s2) != 0)
5225 	return FALSE;
5226 
5227     /* empty dict and NULL dict is different */
5228     d1 = tv1->v_type == VAR_FUNC ? NULL : tv1->vval.v_partial->pt_dict;
5229     d2 = tv2->v_type == VAR_FUNC ? NULL : tv2->vval.v_partial->pt_dict;
5230     if (d1 == NULL || d2 == NULL)
5231     {
5232 	if (d1 != d2)
5233 	    return FALSE;
5234     }
5235     else if (!dict_equal(d1, d2, ic, TRUE))
5236 	return FALSE;
5237 
5238     /* empty list and no list considered the same */
5239     a1 = tv1->v_type == VAR_FUNC ? 0 : tv1->vval.v_partial->pt_argc;
5240     a2 = tv2->v_type == VAR_FUNC ? 0 : tv2->vval.v_partial->pt_argc;
5241     if (a1 != a2)
5242 	return FALSE;
5243     for (i = 0; i < a1; ++i)
5244 	if (!tv_equal(tv1->vval.v_partial->pt_argv + i,
5245 		      tv2->vval.v_partial->pt_argv + i, ic, TRUE))
5246 	    return FALSE;
5247 
5248     return TRUE;
5249 }
5250 
5251 /*
5252  * Return TRUE if "tv1" and "tv2" have the same value.
5253  * Compares the items just like "==" would compare them, but strings and
5254  * numbers are different.  Floats and numbers are also different.
5255  */
5256     int
5257 tv_equal(
5258     typval_T *tv1,
5259     typval_T *tv2,
5260     int	     ic,	    /* ignore case */
5261     int	     recursive)	    /* TRUE when used recursively */
5262 {
5263     char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
5264     char_u	*s1, *s2;
5265     static int  recursive_cnt = 0;	    /* catch recursive loops */
5266     int		r;
5267 
5268     /* Catch lists and dicts that have an endless loop by limiting
5269      * recursiveness to a limit.  We guess they are equal then.
5270      * A fixed limit has the problem of still taking an awful long time.
5271      * Reduce the limit every time running into it. That should work fine for
5272      * deeply linked structures that are not recursively linked and catch
5273      * recursiveness quickly. */
5274     if (!recursive)
5275 	tv_equal_recurse_limit = 1000;
5276     if (recursive_cnt >= tv_equal_recurse_limit)
5277     {
5278 	--tv_equal_recurse_limit;
5279 	return TRUE;
5280     }
5281 
5282     /* For VAR_FUNC and VAR_PARTIAL compare the function name, bound dict and
5283      * arguments. */
5284     if ((tv1->v_type == VAR_FUNC
5285 		|| (tv1->v_type == VAR_PARTIAL && tv1->vval.v_partial != NULL))
5286 	    && (tv2->v_type == VAR_FUNC
5287 		|| (tv2->v_type == VAR_PARTIAL && tv2->vval.v_partial != NULL)))
5288     {
5289 	++recursive_cnt;
5290 	r = func_equal(tv1, tv2, ic);
5291 	--recursive_cnt;
5292 	return r;
5293     }
5294 
5295     if (tv1->v_type != tv2->v_type)
5296 	return FALSE;
5297 
5298     switch (tv1->v_type)
5299     {
5300 	case VAR_LIST:
5301 	    ++recursive_cnt;
5302 	    r = list_equal(tv1->vval.v_list, tv2->vval.v_list, ic, TRUE);
5303 	    --recursive_cnt;
5304 	    return r;
5305 
5306 	case VAR_DICT:
5307 	    ++recursive_cnt;
5308 	    r = dict_equal(tv1->vval.v_dict, tv2->vval.v_dict, ic, TRUE);
5309 	    --recursive_cnt;
5310 	    return r;
5311 
5312 	case VAR_BLOB:
5313 	    return blob_equal(tv1->vval.v_blob, tv2->vval.v_blob);
5314 
5315 	case VAR_NUMBER:
5316 	    return tv1->vval.v_number == tv2->vval.v_number;
5317 
5318 	case VAR_STRING:
5319 	    s1 = tv_get_string_buf(tv1, buf1);
5320 	    s2 = tv_get_string_buf(tv2, buf2);
5321 	    return ((ic ? MB_STRICMP(s1, s2) : STRCMP(s1, s2)) == 0);
5322 
5323 	case VAR_SPECIAL:
5324 	    return tv1->vval.v_number == tv2->vval.v_number;
5325 
5326 	case VAR_FLOAT:
5327 #ifdef FEAT_FLOAT
5328 	    return tv1->vval.v_float == tv2->vval.v_float;
5329 #endif
5330 	case VAR_JOB:
5331 #ifdef FEAT_JOB_CHANNEL
5332 	    return tv1->vval.v_job == tv2->vval.v_job;
5333 #endif
5334 	case VAR_CHANNEL:
5335 #ifdef FEAT_JOB_CHANNEL
5336 	    return tv1->vval.v_channel == tv2->vval.v_channel;
5337 #endif
5338 	case VAR_FUNC:
5339 	case VAR_PARTIAL:
5340 	case VAR_UNKNOWN:
5341 	    break;
5342     }
5343 
5344     /* VAR_UNKNOWN can be the result of a invalid expression, let's say it
5345      * does not equal anything, not even itself. */
5346     return FALSE;
5347 }
5348 
5349 /*
5350  * Return the next (unique) copy ID.
5351  * Used for serializing nested structures.
5352  */
5353     int
5354 get_copyID(void)
5355 {
5356     current_copyID += COPYID_INC;
5357     return current_copyID;
5358 }
5359 
5360 /*
5361  * Garbage collection for lists and dictionaries.
5362  *
5363  * We use reference counts to be able to free most items right away when they
5364  * are no longer used.  But for composite items it's possible that it becomes
5365  * unused while the reference count is > 0: When there is a recursive
5366  * reference.  Example:
5367  *	:let l = [1, 2, 3]
5368  *	:let d = {9: l}
5369  *	:let l[1] = d
5370  *
5371  * Since this is quite unusual we handle this with garbage collection: every
5372  * once in a while find out which lists and dicts are not referenced from any
5373  * variable.
5374  *
5375  * Here is a good reference text about garbage collection (refers to Python
5376  * but it applies to all reference-counting mechanisms):
5377  *	http://python.ca/nas/python/gc/
5378  */
5379 
5380 /*
5381  * Do garbage collection for lists and dicts.
5382  * When "testing" is TRUE this is called from test_garbagecollect_now().
5383  * Return TRUE if some memory was freed.
5384  */
5385     int
5386 garbage_collect(int testing)
5387 {
5388     int		copyID;
5389     int		abort = FALSE;
5390     buf_T	*buf;
5391     win_T	*wp;
5392     int		i;
5393     int		did_free = FALSE;
5394     tabpage_T	*tp;
5395 
5396     if (!testing)
5397     {
5398 	/* Only do this once. */
5399 	want_garbage_collect = FALSE;
5400 	may_garbage_collect = FALSE;
5401 	garbage_collect_at_exit = FALSE;
5402     }
5403 
5404     /* We advance by two because we add one for items referenced through
5405      * previous_funccal. */
5406     copyID = get_copyID();
5407 
5408     /*
5409      * 1. Go through all accessible variables and mark all lists and dicts
5410      *    with copyID.
5411      */
5412 
5413     /* Don't free variables in the previous_funccal list unless they are only
5414      * referenced through previous_funccal.  This must be first, because if
5415      * the item is referenced elsewhere the funccal must not be freed. */
5416     abort = abort || set_ref_in_previous_funccal(copyID);
5417 
5418     /* script-local variables */
5419     for (i = 1; i <= ga_scripts.ga_len; ++i)
5420 	abort = abort || set_ref_in_ht(&SCRIPT_VARS(i), copyID, NULL);
5421 
5422     /* buffer-local variables */
5423     FOR_ALL_BUFFERS(buf)
5424 	abort = abort || set_ref_in_item(&buf->b_bufvar.di_tv, copyID,
5425 								  NULL, NULL);
5426 
5427     /* window-local variables */
5428     FOR_ALL_TAB_WINDOWS(tp, wp)
5429 	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
5430 								  NULL, NULL);
5431     if (aucmd_win != NULL)
5432 	abort = abort || set_ref_in_item(&aucmd_win->w_winvar.di_tv, copyID,
5433 								  NULL, NULL);
5434 
5435     /* tabpage-local variables */
5436     FOR_ALL_TABPAGES(tp)
5437 	abort = abort || set_ref_in_item(&tp->tp_winvar.di_tv, copyID,
5438 								  NULL, NULL);
5439     /* global variables */
5440     abort = abort || set_ref_in_ht(&globvarht, copyID, NULL);
5441 
5442     /* function-local variables */
5443     abort = abort || set_ref_in_call_stack(copyID);
5444 
5445     /* named functions (matters for closures) */
5446     abort = abort || set_ref_in_functions(copyID);
5447 
5448     /* function call arguments, if v:testing is set. */
5449     abort = abort || set_ref_in_func_args(copyID);
5450 
5451     /* v: vars */
5452     abort = abort || set_ref_in_ht(&vimvarht, copyID, NULL);
5453 
5454 #ifdef FEAT_LUA
5455     abort = abort || set_ref_in_lua(copyID);
5456 #endif
5457 
5458 #ifdef FEAT_PYTHON
5459     abort = abort || set_ref_in_python(copyID);
5460 #endif
5461 
5462 #ifdef FEAT_PYTHON3
5463     abort = abort || set_ref_in_python3(copyID);
5464 #endif
5465 
5466 #ifdef FEAT_JOB_CHANNEL
5467     abort = abort || set_ref_in_channel(copyID);
5468     abort = abort || set_ref_in_job(copyID);
5469 #endif
5470 #ifdef FEAT_NETBEANS_INTG
5471     abort = abort || set_ref_in_nb_channel(copyID);
5472 #endif
5473 
5474 #ifdef FEAT_TIMERS
5475     abort = abort || set_ref_in_timer(copyID);
5476 #endif
5477 
5478 #ifdef FEAT_QUICKFIX
5479     abort = abort || set_ref_in_quickfix(copyID);
5480 #endif
5481 
5482 #ifdef FEAT_TERMINAL
5483     abort = abort || set_ref_in_term(copyID);
5484 #endif
5485 
5486     if (!abort)
5487     {
5488 	/*
5489 	 * 2. Free lists and dictionaries that are not referenced.
5490 	 */
5491 	did_free = free_unref_items(copyID);
5492 
5493 	/*
5494 	 * 3. Check if any funccal can be freed now.
5495 	 *    This may call us back recursively.
5496 	 */
5497 	free_unref_funccal(copyID, testing);
5498     }
5499     else if (p_verbose > 0)
5500     {
5501 	verb_msg(_("Not enough memory to set references, garbage collection aborted!"));
5502     }
5503 
5504     return did_free;
5505 }
5506 
5507 /*
5508  * Free lists, dictionaries, channels and jobs that are no longer referenced.
5509  */
5510     static int
5511 free_unref_items(int copyID)
5512 {
5513     int		did_free = FALSE;
5514 
5515     /* Let all "free" functions know that we are here.  This means no
5516      * dictionaries, lists, channels or jobs are to be freed, because we will
5517      * do that here. */
5518     in_free_unref_items = TRUE;
5519 
5520     /*
5521      * PASS 1: free the contents of the items.  We don't free the items
5522      * themselves yet, so that it is possible to decrement refcount counters
5523      */
5524 
5525     /* Go through the list of dicts and free items without the copyID. */
5526     did_free |= dict_free_nonref(copyID);
5527 
5528     /* Go through the list of lists and free items without the copyID. */
5529     did_free |= list_free_nonref(copyID);
5530 
5531 #ifdef FEAT_JOB_CHANNEL
5532     /* Go through the list of jobs and free items without the copyID. This
5533      * must happen before doing channels, because jobs refer to channels, but
5534      * the reference from the channel to the job isn't tracked. */
5535     did_free |= free_unused_jobs_contents(copyID, COPYID_MASK);
5536 
5537     /* Go through the list of channels and free items without the copyID.  */
5538     did_free |= free_unused_channels_contents(copyID, COPYID_MASK);
5539 #endif
5540 
5541     /*
5542      * PASS 2: free the items themselves.
5543      */
5544     dict_free_items(copyID);
5545     list_free_items(copyID);
5546 
5547 #ifdef FEAT_JOB_CHANNEL
5548     /* Go through the list of jobs and free items without the copyID. This
5549      * must happen before doing channels, because jobs refer to channels, but
5550      * the reference from the channel to the job isn't tracked. */
5551     free_unused_jobs(copyID, COPYID_MASK);
5552 
5553     /* Go through the list of channels and free items without the copyID.  */
5554     free_unused_channels(copyID, COPYID_MASK);
5555 #endif
5556 
5557     in_free_unref_items = FALSE;
5558 
5559     return did_free;
5560 }
5561 
5562 /*
5563  * Mark all lists and dicts referenced through hashtab "ht" with "copyID".
5564  * "list_stack" is used to add lists to be marked.  Can be NULL.
5565  *
5566  * Returns TRUE if setting references failed somehow.
5567  */
5568     int
5569 set_ref_in_ht(hashtab_T *ht, int copyID, list_stack_T **list_stack)
5570 {
5571     int		todo;
5572     int		abort = FALSE;
5573     hashitem_T	*hi;
5574     hashtab_T	*cur_ht;
5575     ht_stack_T	*ht_stack = NULL;
5576     ht_stack_T	*tempitem;
5577 
5578     cur_ht = ht;
5579     for (;;)
5580     {
5581 	if (!abort)
5582 	{
5583 	    /* Mark each item in the hashtab.  If the item contains a hashtab
5584 	     * it is added to ht_stack, if it contains a list it is added to
5585 	     * list_stack. */
5586 	    todo = (int)cur_ht->ht_used;
5587 	    for (hi = cur_ht->ht_array; todo > 0; ++hi)
5588 		if (!HASHITEM_EMPTY(hi))
5589 		{
5590 		    --todo;
5591 		    abort = abort || set_ref_in_item(&HI2DI(hi)->di_tv, copyID,
5592 						       &ht_stack, list_stack);
5593 		}
5594 	}
5595 
5596 	if (ht_stack == NULL)
5597 	    break;
5598 
5599 	/* take an item from the stack */
5600 	cur_ht = ht_stack->ht;
5601 	tempitem = ht_stack;
5602 	ht_stack = ht_stack->prev;
5603 	free(tempitem);
5604     }
5605 
5606     return abort;
5607 }
5608 
5609 /*
5610  * Mark all lists and dicts referenced through list "l" with "copyID".
5611  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
5612  *
5613  * Returns TRUE if setting references failed somehow.
5614  */
5615     int
5616 set_ref_in_list(list_T *l, int copyID, ht_stack_T **ht_stack)
5617 {
5618     listitem_T	 *li;
5619     int		 abort = FALSE;
5620     list_T	 *cur_l;
5621     list_stack_T *list_stack = NULL;
5622     list_stack_T *tempitem;
5623 
5624     cur_l = l;
5625     for (;;)
5626     {
5627 	if (!abort)
5628 	    /* Mark each item in the list.  If the item contains a hashtab
5629 	     * it is added to ht_stack, if it contains a list it is added to
5630 	     * list_stack. */
5631 	    for (li = cur_l->lv_first; !abort && li != NULL; li = li->li_next)
5632 		abort = abort || set_ref_in_item(&li->li_tv, copyID,
5633 						       ht_stack, &list_stack);
5634 	if (list_stack == NULL)
5635 	    break;
5636 
5637 	/* take an item from the stack */
5638 	cur_l = list_stack->list;
5639 	tempitem = list_stack;
5640 	list_stack = list_stack->prev;
5641 	free(tempitem);
5642     }
5643 
5644     return abort;
5645 }
5646 
5647 /*
5648  * Mark all lists and dicts referenced through typval "tv" with "copyID".
5649  * "list_stack" is used to add lists to be marked.  Can be NULL.
5650  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
5651  *
5652  * Returns TRUE if setting references failed somehow.
5653  */
5654     int
5655 set_ref_in_item(
5656     typval_T	    *tv,
5657     int		    copyID,
5658     ht_stack_T	    **ht_stack,
5659     list_stack_T    **list_stack)
5660 {
5661     int		abort = FALSE;
5662 
5663     if (tv->v_type == VAR_DICT)
5664     {
5665 	dict_T	*dd = tv->vval.v_dict;
5666 
5667 	if (dd != NULL && dd->dv_copyID != copyID)
5668 	{
5669 	    /* Didn't see this dict yet. */
5670 	    dd->dv_copyID = copyID;
5671 	    if (ht_stack == NULL)
5672 	    {
5673 		abort = set_ref_in_ht(&dd->dv_hashtab, copyID, list_stack);
5674 	    }
5675 	    else
5676 	    {
5677 		ht_stack_T *newitem = (ht_stack_T*)malloc(sizeof(ht_stack_T));
5678 		if (newitem == NULL)
5679 		    abort = TRUE;
5680 		else
5681 		{
5682 		    newitem->ht = &dd->dv_hashtab;
5683 		    newitem->prev = *ht_stack;
5684 		    *ht_stack = newitem;
5685 		}
5686 	    }
5687 	}
5688     }
5689     else if (tv->v_type == VAR_LIST)
5690     {
5691 	list_T	*ll = tv->vval.v_list;
5692 
5693 	if (ll != NULL && ll->lv_copyID != copyID)
5694 	{
5695 	    /* Didn't see this list yet. */
5696 	    ll->lv_copyID = copyID;
5697 	    if (list_stack == NULL)
5698 	    {
5699 		abort = set_ref_in_list(ll, copyID, ht_stack);
5700 	    }
5701 	    else
5702 	    {
5703 		list_stack_T *newitem = (list_stack_T*)malloc(
5704 							sizeof(list_stack_T));
5705 		if (newitem == NULL)
5706 		    abort = TRUE;
5707 		else
5708 		{
5709 		    newitem->list = ll;
5710 		    newitem->prev = *list_stack;
5711 		    *list_stack = newitem;
5712 		}
5713 	    }
5714 	}
5715     }
5716     else if (tv->v_type == VAR_FUNC)
5717     {
5718 	abort = set_ref_in_func(tv->vval.v_string, NULL, copyID);
5719     }
5720     else if (tv->v_type == VAR_PARTIAL)
5721     {
5722 	partial_T	*pt = tv->vval.v_partial;
5723 	int		i;
5724 
5725 	/* A partial does not have a copyID, because it cannot contain itself.
5726 	 */
5727 	if (pt != NULL)
5728 	{
5729 	    abort = set_ref_in_func(pt->pt_name, pt->pt_func, copyID);
5730 
5731 	    if (pt->pt_dict != NULL)
5732 	    {
5733 		typval_T dtv;
5734 
5735 		dtv.v_type = VAR_DICT;
5736 		dtv.vval.v_dict = pt->pt_dict;
5737 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5738 	    }
5739 
5740 	    for (i = 0; i < pt->pt_argc; ++i)
5741 		abort = abort || set_ref_in_item(&pt->pt_argv[i], copyID,
5742 							ht_stack, list_stack);
5743 	}
5744     }
5745 #ifdef FEAT_JOB_CHANNEL
5746     else if (tv->v_type == VAR_JOB)
5747     {
5748 	job_T	    *job = tv->vval.v_job;
5749 	typval_T    dtv;
5750 
5751 	if (job != NULL && job->jv_copyID != copyID)
5752 	{
5753 	    job->jv_copyID = copyID;
5754 	    if (job->jv_channel != NULL)
5755 	    {
5756 		dtv.v_type = VAR_CHANNEL;
5757 		dtv.vval.v_channel = job->jv_channel;
5758 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5759 	    }
5760 	    if (job->jv_exit_partial != NULL)
5761 	    {
5762 		dtv.v_type = VAR_PARTIAL;
5763 		dtv.vval.v_partial = job->jv_exit_partial;
5764 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5765 	    }
5766 	}
5767     }
5768     else if (tv->v_type == VAR_CHANNEL)
5769     {
5770 	channel_T   *ch =tv->vval.v_channel;
5771 	ch_part_T   part;
5772 	typval_T    dtv;
5773 	jsonq_T	    *jq;
5774 	cbq_T	    *cq;
5775 
5776 	if (ch != NULL && ch->ch_copyID != copyID)
5777 	{
5778 	    ch->ch_copyID = copyID;
5779 	    for (part = PART_SOCK; part < PART_COUNT; ++part)
5780 	    {
5781 		for (jq = ch->ch_part[part].ch_json_head.jq_next; jq != NULL;
5782 							     jq = jq->jq_next)
5783 		    set_ref_in_item(jq->jq_value, copyID, ht_stack, list_stack);
5784 		for (cq = ch->ch_part[part].ch_cb_head.cq_next; cq != NULL;
5785 							     cq = cq->cq_next)
5786 		    if (cq->cq_partial != NULL)
5787 		    {
5788 			dtv.v_type = VAR_PARTIAL;
5789 			dtv.vval.v_partial = cq->cq_partial;
5790 			set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5791 		    }
5792 		if (ch->ch_part[part].ch_partial != NULL)
5793 		{
5794 		    dtv.v_type = VAR_PARTIAL;
5795 		    dtv.vval.v_partial = ch->ch_part[part].ch_partial;
5796 		    set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5797 		}
5798 	    }
5799 	    if (ch->ch_partial != NULL)
5800 	    {
5801 		dtv.v_type = VAR_PARTIAL;
5802 		dtv.vval.v_partial = ch->ch_partial;
5803 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5804 	    }
5805 	    if (ch->ch_close_partial != NULL)
5806 	    {
5807 		dtv.v_type = VAR_PARTIAL;
5808 		dtv.vval.v_partial = ch->ch_close_partial;
5809 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5810 	    }
5811 	}
5812     }
5813 #endif
5814     return abort;
5815 }
5816 
5817     static char *
5818 get_var_special_name(int nr)
5819 {
5820     switch (nr)
5821     {
5822 	case VVAL_FALSE: return "v:false";
5823 	case VVAL_TRUE:  return "v:true";
5824 	case VVAL_NONE:  return "v:none";
5825 	case VVAL_NULL:  return "v:null";
5826     }
5827     internal_error("get_var_special_name()");
5828     return "42";
5829 }
5830 
5831 /*
5832  * Return a string with the string representation of a variable.
5833  * If the memory is allocated "tofree" is set to it, otherwise NULL.
5834  * "numbuf" is used for a number.
5835  * When "copyID" is not NULL replace recursive lists and dicts with "...".
5836  * When both "echo_style" and "composite_val" are FALSE, put quotes around
5837  * stings as "string()", otherwise does not put quotes around strings, as
5838  * ":echo" displays values.
5839  * When "restore_copyID" is FALSE, repeated items in dictionaries and lists
5840  * are replaced with "...".
5841  * May return NULL.
5842  */
5843     char_u *
5844 echo_string_core(
5845     typval_T	*tv,
5846     char_u	**tofree,
5847     char_u	*numbuf,
5848     int		copyID,
5849     int		echo_style,
5850     int		restore_copyID,
5851     int		composite_val)
5852 {
5853     static int	recurse = 0;
5854     char_u	*r = NULL;
5855 
5856     if (recurse >= DICT_MAXNEST)
5857     {
5858 	if (!did_echo_string_emsg)
5859 	{
5860 	    /* Only give this message once for a recursive call to avoid
5861 	     * flooding the user with errors.  And stop iterating over lists
5862 	     * and dicts. */
5863 	    did_echo_string_emsg = TRUE;
5864 	    emsg(_("E724: variable nested too deep for displaying"));
5865 	}
5866 	*tofree = NULL;
5867 	return (char_u *)"{E724}";
5868     }
5869     ++recurse;
5870 
5871     switch (tv->v_type)
5872     {
5873 	case VAR_STRING:
5874 	    if (echo_style && !composite_val)
5875 	    {
5876 		*tofree = NULL;
5877 		r = tv->vval.v_string;
5878 		if (r == NULL)
5879 		    r = (char_u *)"";
5880 	    }
5881 	    else
5882 	    {
5883 		*tofree = string_quote(tv->vval.v_string, FALSE);
5884 		r = *tofree;
5885 	    }
5886 	    break;
5887 
5888 	case VAR_FUNC:
5889 	    if (echo_style)
5890 	    {
5891 		*tofree = NULL;
5892 		r = tv->vval.v_string;
5893 	    }
5894 	    else
5895 	    {
5896 		*tofree = string_quote(tv->vval.v_string, TRUE);
5897 		r = *tofree;
5898 	    }
5899 	    break;
5900 
5901 	case VAR_PARTIAL:
5902 	    {
5903 		partial_T   *pt = tv->vval.v_partial;
5904 		char_u	    *fname = string_quote(pt == NULL ? NULL
5905 						    : partial_name(pt), FALSE);
5906 		garray_T    ga;
5907 		int	    i;
5908 		char_u	    *tf;
5909 
5910 		ga_init2(&ga, 1, 100);
5911 		ga_concat(&ga, (char_u *)"function(");
5912 		if (fname != NULL)
5913 		{
5914 		    ga_concat(&ga, fname);
5915 		    vim_free(fname);
5916 		}
5917 		if (pt != NULL && pt->pt_argc > 0)
5918 		{
5919 		    ga_concat(&ga, (char_u *)", [");
5920 		    for (i = 0; i < pt->pt_argc; ++i)
5921 		    {
5922 			if (i > 0)
5923 			    ga_concat(&ga, (char_u *)", ");
5924 			ga_concat(&ga,
5925 			     tv2string(&pt->pt_argv[i], &tf, numbuf, copyID));
5926 			vim_free(tf);
5927 		    }
5928 		    ga_concat(&ga, (char_u *)"]");
5929 		}
5930 		if (pt != NULL && pt->pt_dict != NULL)
5931 		{
5932 		    typval_T dtv;
5933 
5934 		    ga_concat(&ga, (char_u *)", ");
5935 		    dtv.v_type = VAR_DICT;
5936 		    dtv.vval.v_dict = pt->pt_dict;
5937 		    ga_concat(&ga, tv2string(&dtv, &tf, numbuf, copyID));
5938 		    vim_free(tf);
5939 		}
5940 		ga_concat(&ga, (char_u *)")");
5941 
5942 		*tofree = ga.ga_data;
5943 		r = *tofree;
5944 		break;
5945 	    }
5946 
5947 	case VAR_BLOB:
5948 	    r = blob2string(tv->vval.v_blob, tofree, numbuf);
5949 	    break;
5950 
5951 	case VAR_LIST:
5952 	    if (tv->vval.v_list == NULL)
5953 	    {
5954 		*tofree = NULL;
5955 		r = NULL;
5956 	    }
5957 	    else if (copyID != 0 && tv->vval.v_list->lv_copyID == copyID
5958 		    && tv->vval.v_list->lv_len > 0)
5959 	    {
5960 		*tofree = NULL;
5961 		r = (char_u *)"[...]";
5962 	    }
5963 	    else
5964 	    {
5965 		int old_copyID = tv->vval.v_list->lv_copyID;
5966 
5967 		tv->vval.v_list->lv_copyID = copyID;
5968 		*tofree = list2string(tv, copyID, restore_copyID);
5969 		if (restore_copyID)
5970 		    tv->vval.v_list->lv_copyID = old_copyID;
5971 		r = *tofree;
5972 	    }
5973 	    break;
5974 
5975 	case VAR_DICT:
5976 	    if (tv->vval.v_dict == NULL)
5977 	    {
5978 		*tofree = NULL;
5979 		r = NULL;
5980 	    }
5981 	    else if (copyID != 0 && tv->vval.v_dict->dv_copyID == copyID
5982 		    && tv->vval.v_dict->dv_hashtab.ht_used != 0)
5983 	    {
5984 		*tofree = NULL;
5985 		r = (char_u *)"{...}";
5986 	    }
5987 	    else
5988 	    {
5989 		int old_copyID = tv->vval.v_dict->dv_copyID;
5990 		tv->vval.v_dict->dv_copyID = copyID;
5991 		*tofree = dict2string(tv, copyID, restore_copyID);
5992 		if (restore_copyID)
5993 		    tv->vval.v_dict->dv_copyID = old_copyID;
5994 		r = *tofree;
5995 	    }
5996 	    break;
5997 
5998 	case VAR_NUMBER:
5999 	case VAR_UNKNOWN:
6000 	    *tofree = NULL;
6001 	    r = tv_get_string_buf(tv, numbuf);
6002 	    break;
6003 
6004 	case VAR_JOB:
6005 	case VAR_CHANNEL:
6006 	    *tofree = NULL;
6007 	    r = tv_get_string_buf(tv, numbuf);
6008 	    if (composite_val)
6009 	    {
6010 		*tofree = string_quote(r, FALSE);
6011 		r = *tofree;
6012 	    }
6013 	    break;
6014 
6015 	case VAR_FLOAT:
6016 #ifdef FEAT_FLOAT
6017 	    *tofree = NULL;
6018 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv->vval.v_float);
6019 	    r = numbuf;
6020 	    break;
6021 #endif
6022 
6023 	case VAR_SPECIAL:
6024 	    *tofree = NULL;
6025 	    r = (char_u *)get_var_special_name(tv->vval.v_number);
6026 	    break;
6027     }
6028 
6029     if (--recurse == 0)
6030 	did_echo_string_emsg = FALSE;
6031     return r;
6032 }
6033 
6034 /*
6035  * Return a string with the string representation of a variable.
6036  * If the memory is allocated "tofree" is set to it, otherwise NULL.
6037  * "numbuf" is used for a number.
6038  * Does not put quotes around strings, as ":echo" displays values.
6039  * When "copyID" is not NULL replace recursive lists and dicts with "...".
6040  * May return NULL.
6041  */
6042     char_u *
6043 echo_string(
6044     typval_T	*tv,
6045     char_u	**tofree,
6046     char_u	*numbuf,
6047     int		copyID)
6048 {
6049     return echo_string_core(tv, tofree, numbuf, copyID, TRUE, FALSE, FALSE);
6050 }
6051 
6052 /*
6053  * Return a string with the string representation of a variable.
6054  * If the memory is allocated "tofree" is set to it, otherwise NULL.
6055  * "numbuf" is used for a number.
6056  * Puts quotes around strings, so that they can be parsed back by eval().
6057  * May return NULL.
6058  */
6059     char_u *
6060 tv2string(
6061     typval_T	*tv,
6062     char_u	**tofree,
6063     char_u	*numbuf,
6064     int		copyID)
6065 {
6066     return echo_string_core(tv, tofree, numbuf, copyID, FALSE, TRUE, FALSE);
6067 }
6068 
6069 /*
6070  * Return string "str" in ' quotes, doubling ' characters.
6071  * If "str" is NULL an empty string is assumed.
6072  * If "function" is TRUE make it function('string').
6073  */
6074     char_u *
6075 string_quote(char_u *str, int function)
6076 {
6077     unsigned	len;
6078     char_u	*p, *r, *s;
6079 
6080     len = (function ? 13 : 3);
6081     if (str != NULL)
6082     {
6083 	len += (unsigned)STRLEN(str);
6084 	for (p = str; *p != NUL; MB_PTR_ADV(p))
6085 	    if (*p == '\'')
6086 		++len;
6087     }
6088     s = r = alloc(len);
6089     if (r != NULL)
6090     {
6091 	if (function)
6092 	{
6093 	    STRCPY(r, "function('");
6094 	    r += 10;
6095 	}
6096 	else
6097 	    *r++ = '\'';
6098 	if (str != NULL)
6099 	    for (p = str; *p != NUL; )
6100 	    {
6101 		if (*p == '\'')
6102 		    *r++ = '\'';
6103 		MB_COPY_CHAR(p, r);
6104 	    }
6105 	*r++ = '\'';
6106 	if (function)
6107 	    *r++ = ')';
6108 	*r++ = NUL;
6109     }
6110     return s;
6111 }
6112 
6113 #if defined(FEAT_FLOAT) || defined(PROTO)
6114 /*
6115  * Convert the string "text" to a floating point number.
6116  * This uses strtod().  setlocale(LC_NUMERIC, "C") has been used to make sure
6117  * this always uses a decimal point.
6118  * Returns the length of the text that was consumed.
6119  */
6120     int
6121 string2float(
6122     char_u	*text,
6123     float_T	*value)	    /* result stored here */
6124 {
6125     char	*s = (char *)text;
6126     float_T	f;
6127 
6128     /* MS-Windows does not deal with "inf" and "nan" properly. */
6129     if (STRNICMP(text, "inf", 3) == 0)
6130     {
6131 	*value = INFINITY;
6132 	return 3;
6133     }
6134     if (STRNICMP(text, "-inf", 3) == 0)
6135     {
6136 	*value = -INFINITY;
6137 	return 4;
6138     }
6139     if (STRNICMP(text, "nan", 3) == 0)
6140     {
6141 	*value = NAN;
6142 	return 3;
6143     }
6144     f = strtod(s, &s);
6145     *value = f;
6146     return (int)((char_u *)s - text);
6147 }
6148 #endif
6149 
6150 /*
6151  * Get the value of an environment variable.
6152  * "arg" is pointing to the '$'.  It is advanced to after the name.
6153  * If the environment variable was not set, silently assume it is empty.
6154  * Return FAIL if the name is invalid.
6155  */
6156     static int
6157 get_env_tv(char_u **arg, typval_T *rettv, int evaluate)
6158 {
6159     char_u	*string = NULL;
6160     int		len;
6161     int		cc;
6162     char_u	*name;
6163     int		mustfree = FALSE;
6164 
6165     ++*arg;
6166     name = *arg;
6167     len = get_env_len(arg);
6168     if (evaluate)
6169     {
6170 	if (len == 0)
6171 	    return FAIL; /* invalid empty name */
6172 
6173 	cc = name[len];
6174 	name[len] = NUL;
6175 	/* first try vim_getenv(), fast for normal environment vars */
6176 	string = vim_getenv(name, &mustfree);
6177 	if (string != NULL && *string != NUL)
6178 	{
6179 	    if (!mustfree)
6180 		string = vim_strsave(string);
6181 	}
6182 	else
6183 	{
6184 	    if (mustfree)
6185 		vim_free(string);
6186 
6187 	    /* next try expanding things like $VIM and ${HOME} */
6188 	    string = expand_env_save(name - 1);
6189 	    if (string != NULL && *string == '$')
6190 		VIM_CLEAR(string);
6191 	}
6192 	name[len] = cc;
6193 
6194 	rettv->v_type = VAR_STRING;
6195 	rettv->vval.v_string = string;
6196     }
6197 
6198     return OK;
6199 }
6200 
6201 
6202 
6203 /*
6204  * Translate a String variable into a position.
6205  * Returns NULL when there is an error.
6206  */
6207     pos_T *
6208 var2fpos(
6209     typval_T	*varp,
6210     int		dollar_lnum,	/* TRUE when $ is last line */
6211     int		*fnum)		/* set to fnum for '0, 'A, etc. */
6212 {
6213     char_u		*name;
6214     static pos_T	pos;
6215     pos_T		*pp;
6216 
6217     /* Argument can be [lnum, col, coladd]. */
6218     if (varp->v_type == VAR_LIST)
6219     {
6220 	list_T		*l;
6221 	int		len;
6222 	int		error = FALSE;
6223 	listitem_T	*li;
6224 
6225 	l = varp->vval.v_list;
6226 	if (l == NULL)
6227 	    return NULL;
6228 
6229 	/* Get the line number */
6230 	pos.lnum = list_find_nr(l, 0L, &error);
6231 	if (error || pos.lnum <= 0 || pos.lnum > curbuf->b_ml.ml_line_count)
6232 	    return NULL;	/* invalid line number */
6233 
6234 	/* Get the column number */
6235 	pos.col = list_find_nr(l, 1L, &error);
6236 	if (error)
6237 	    return NULL;
6238 	len = (long)STRLEN(ml_get(pos.lnum));
6239 
6240 	/* We accept "$" for the column number: last column. */
6241 	li = list_find(l, 1L);
6242 	if (li != NULL && li->li_tv.v_type == VAR_STRING
6243 		&& li->li_tv.vval.v_string != NULL
6244 		&& STRCMP(li->li_tv.vval.v_string, "$") == 0)
6245 	    pos.col = len + 1;
6246 
6247 	/* Accept a position up to the NUL after the line. */
6248 	if (pos.col == 0 || (int)pos.col > len + 1)
6249 	    return NULL;	/* invalid column number */
6250 	--pos.col;
6251 
6252 	/* Get the virtual offset.  Defaults to zero. */
6253 	pos.coladd = list_find_nr(l, 2L, &error);
6254 	if (error)
6255 	    pos.coladd = 0;
6256 
6257 	return &pos;
6258     }
6259 
6260     name = tv_get_string_chk(varp);
6261     if (name == NULL)
6262 	return NULL;
6263     if (name[0] == '.')				/* cursor */
6264 	return &curwin->w_cursor;
6265     if (name[0] == 'v' && name[1] == NUL)	/* Visual start */
6266     {
6267 	if (VIsual_active)
6268 	    return &VIsual;
6269 	return &curwin->w_cursor;
6270     }
6271     if (name[0] == '\'')			/* mark */
6272     {
6273 	pp = getmark_buf_fnum(curbuf, name[1], FALSE, fnum);
6274 	if (pp == NULL || pp == (pos_T *)-1 || pp->lnum <= 0)
6275 	    return NULL;
6276 	return pp;
6277     }
6278 
6279     pos.coladd = 0;
6280 
6281     if (name[0] == 'w' && dollar_lnum)
6282     {
6283 	pos.col = 0;
6284 	if (name[1] == '0')		/* "w0": first visible line */
6285 	{
6286 	    update_topline();
6287 	    /* In silent Ex mode topline is zero, but that's not a valid line
6288 	     * number; use one instead. */
6289 	    pos.lnum = curwin->w_topline > 0 ? curwin->w_topline : 1;
6290 	    return &pos;
6291 	}
6292 	else if (name[1] == '$')	/* "w$": last visible line */
6293 	{
6294 	    validate_botline();
6295 	    /* In silent Ex mode botline is zero, return zero then. */
6296 	    pos.lnum = curwin->w_botline > 0 ? curwin->w_botline - 1 : 0;
6297 	    return &pos;
6298 	}
6299     }
6300     else if (name[0] == '$')		/* last column or line */
6301     {
6302 	if (dollar_lnum)
6303 	{
6304 	    pos.lnum = curbuf->b_ml.ml_line_count;
6305 	    pos.col = 0;
6306 	}
6307 	else
6308 	{
6309 	    pos.lnum = curwin->w_cursor.lnum;
6310 	    pos.col = (colnr_T)STRLEN(ml_get_curline());
6311 	}
6312 	return &pos;
6313     }
6314     return NULL;
6315 }
6316 
6317 /*
6318  * Convert list in "arg" into a position and optional file number.
6319  * When "fnump" is NULL there is no file number, only 3 items.
6320  * Note that the column is passed on as-is, the caller may want to decrement
6321  * it to use 1 for the first column.
6322  * Return FAIL when conversion is not possible, doesn't check the position for
6323  * validity.
6324  */
6325     int
6326 list2fpos(
6327     typval_T	*arg,
6328     pos_T	*posp,
6329     int		*fnump,
6330     colnr_T	*curswantp)
6331 {
6332     list_T	*l = arg->vval.v_list;
6333     long	i = 0;
6334     long	n;
6335 
6336     /* List must be: [fnum, lnum, col, coladd, curswant], where "fnum" is only
6337      * there when "fnump" isn't NULL; "coladd" and "curswant" are optional. */
6338     if (arg->v_type != VAR_LIST
6339 	    || l == NULL
6340 	    || l->lv_len < (fnump == NULL ? 2 : 3)
6341 	    || l->lv_len > (fnump == NULL ? 4 : 5))
6342 	return FAIL;
6343 
6344     if (fnump != NULL)
6345     {
6346 	n = list_find_nr(l, i++, NULL);	/* fnum */
6347 	if (n < 0)
6348 	    return FAIL;
6349 	if (n == 0)
6350 	    n = curbuf->b_fnum;		/* current buffer */
6351 	*fnump = n;
6352     }
6353 
6354     n = list_find_nr(l, i++, NULL);	/* lnum */
6355     if (n < 0)
6356 	return FAIL;
6357     posp->lnum = n;
6358 
6359     n = list_find_nr(l, i++, NULL);	/* col */
6360     if (n < 0)
6361 	return FAIL;
6362     posp->col = n;
6363 
6364     n = list_find_nr(l, i, NULL);	/* off */
6365     if (n < 0)
6366 	posp->coladd = 0;
6367     else
6368 	posp->coladd = n;
6369 
6370     if (curswantp != NULL)
6371 	*curswantp = list_find_nr(l, i + 1, NULL);  /* curswant */
6372 
6373     return OK;
6374 }
6375 
6376 /*
6377  * Get the length of an environment variable name.
6378  * Advance "arg" to the first character after the name.
6379  * Return 0 for error.
6380  */
6381     static int
6382 get_env_len(char_u **arg)
6383 {
6384     char_u	*p;
6385     int		len;
6386 
6387     for (p = *arg; vim_isIDc(*p); ++p)
6388 	;
6389     if (p == *arg)	    /* no name found */
6390 	return 0;
6391 
6392     len = (int)(p - *arg);
6393     *arg = p;
6394     return len;
6395 }
6396 
6397 /*
6398  * Get the length of the name of a function or internal variable.
6399  * "arg" is advanced to the first non-white character after the name.
6400  * Return 0 if something is wrong.
6401  */
6402     int
6403 get_id_len(char_u **arg)
6404 {
6405     char_u	*p;
6406     int		len;
6407 
6408     /* Find the end of the name. */
6409     for (p = *arg; eval_isnamec(*p); ++p)
6410     {
6411 	if (*p == ':')
6412 	{
6413 	    /* "s:" is start of "s:var", but "n:" is not and can be used in
6414 	     * slice "[n:]".  Also "xx:" is not a namespace. */
6415 	    len = (int)(p - *arg);
6416 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, **arg) == NULL)
6417 		    || len > 1)
6418 		break;
6419 	}
6420     }
6421     if (p == *arg)	    /* no name found */
6422 	return 0;
6423 
6424     len = (int)(p - *arg);
6425     *arg = skipwhite(p);
6426 
6427     return len;
6428 }
6429 
6430 /*
6431  * Get the length of the name of a variable or function.
6432  * Only the name is recognized, does not handle ".key" or "[idx]".
6433  * "arg" is advanced to the first non-white character after the name.
6434  * Return -1 if curly braces expansion failed.
6435  * Return 0 if something else is wrong.
6436  * If the name contains 'magic' {}'s, expand them and return the
6437  * expanded name in an allocated string via 'alias' - caller must free.
6438  */
6439     int
6440 get_name_len(
6441     char_u	**arg,
6442     char_u	**alias,
6443     int		evaluate,
6444     int		verbose)
6445 {
6446     int		len;
6447     char_u	*p;
6448     char_u	*expr_start;
6449     char_u	*expr_end;
6450 
6451     *alias = NULL;  /* default to no alias */
6452 
6453     if ((*arg)[0] == K_SPECIAL && (*arg)[1] == KS_EXTRA
6454 						  && (*arg)[2] == (int)KE_SNR)
6455     {
6456 	/* hard coded <SNR>, already translated */
6457 	*arg += 3;
6458 	return get_id_len(arg) + 3;
6459     }
6460     len = eval_fname_script(*arg);
6461     if (len > 0)
6462     {
6463 	/* literal "<SID>", "s:" or "<SNR>" */
6464 	*arg += len;
6465     }
6466 
6467     /*
6468      * Find the end of the name; check for {} construction.
6469      */
6470     p = find_name_end(*arg, &expr_start, &expr_end,
6471 					       len > 0 ? 0 : FNE_CHECK_START);
6472     if (expr_start != NULL)
6473     {
6474 	char_u	*temp_string;
6475 
6476 	if (!evaluate)
6477 	{
6478 	    len += (int)(p - *arg);
6479 	    *arg = skipwhite(p);
6480 	    return len;
6481 	}
6482 
6483 	/*
6484 	 * Include any <SID> etc in the expanded string:
6485 	 * Thus the -len here.
6486 	 */
6487 	temp_string = make_expanded_name(*arg - len, expr_start, expr_end, p);
6488 	if (temp_string == NULL)
6489 	    return -1;
6490 	*alias = temp_string;
6491 	*arg = skipwhite(p);
6492 	return (int)STRLEN(temp_string);
6493     }
6494 
6495     len += get_id_len(arg);
6496     // Only give an error when there is something, otherwise it will be
6497     // reported at a higher level.
6498     if (len == 0 && verbose && **arg != NUL)
6499 	semsg(_(e_invexpr2), *arg);
6500 
6501     return len;
6502 }
6503 
6504 /*
6505  * Find the end of a variable or function name, taking care of magic braces.
6506  * If "expr_start" is not NULL then "expr_start" and "expr_end" are set to the
6507  * start and end of the first magic braces item.
6508  * "flags" can have FNE_INCL_BR and FNE_CHECK_START.
6509  * Return a pointer to just after the name.  Equal to "arg" if there is no
6510  * valid name.
6511  */
6512     char_u *
6513 find_name_end(
6514     char_u	*arg,
6515     char_u	**expr_start,
6516     char_u	**expr_end,
6517     int		flags)
6518 {
6519     int		mb_nest = 0;
6520     int		br_nest = 0;
6521     char_u	*p;
6522     int		len;
6523 
6524     if (expr_start != NULL)
6525     {
6526 	*expr_start = NULL;
6527 	*expr_end = NULL;
6528     }
6529 
6530     /* Quick check for valid starting character. */
6531     if ((flags & FNE_CHECK_START) && !eval_isnamec1(*arg) && *arg != '{')
6532 	return arg;
6533 
6534     for (p = arg; *p != NUL
6535 		    && (eval_isnamec(*p)
6536 			|| *p == '{'
6537 			|| ((flags & FNE_INCL_BR) && (*p == '[' || *p == '.'))
6538 			|| mb_nest != 0
6539 			|| br_nest != 0); MB_PTR_ADV(p))
6540     {
6541 	if (*p == '\'')
6542 	{
6543 	    /* skip over 'string' to avoid counting [ and ] inside it. */
6544 	    for (p = p + 1; *p != NUL && *p != '\''; MB_PTR_ADV(p))
6545 		;
6546 	    if (*p == NUL)
6547 		break;
6548 	}
6549 	else if (*p == '"')
6550 	{
6551 	    /* skip over "str\"ing" to avoid counting [ and ] inside it. */
6552 	    for (p = p + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
6553 		if (*p == '\\' && p[1] != NUL)
6554 		    ++p;
6555 	    if (*p == NUL)
6556 		break;
6557 	}
6558 	else if (br_nest == 0 && mb_nest == 0 && *p == ':')
6559 	{
6560 	    /* "s:" is start of "s:var", but "n:" is not and can be used in
6561 	     * slice "[n:]".  Also "xx:" is not a namespace. But {ns}: is. */
6562 	    len = (int)(p - arg);
6563 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, *arg) == NULL)
6564 		    || (len > 1 && p[-1] != '}'))
6565 		break;
6566 	}
6567 
6568 	if (mb_nest == 0)
6569 	{
6570 	    if (*p == '[')
6571 		++br_nest;
6572 	    else if (*p == ']')
6573 		--br_nest;
6574 	}
6575 
6576 	if (br_nest == 0)
6577 	{
6578 	    if (*p == '{')
6579 	    {
6580 		mb_nest++;
6581 		if (expr_start != NULL && *expr_start == NULL)
6582 		    *expr_start = p;
6583 	    }
6584 	    else if (*p == '}')
6585 	    {
6586 		mb_nest--;
6587 		if (expr_start != NULL && mb_nest == 0 && *expr_end == NULL)
6588 		    *expr_end = p;
6589 	    }
6590 	}
6591     }
6592 
6593     return p;
6594 }
6595 
6596 /*
6597  * Expands out the 'magic' {}'s in a variable/function name.
6598  * Note that this can call itself recursively, to deal with
6599  * constructs like foo{bar}{baz}{bam}
6600  * The four pointer arguments point to "foo{expre}ss{ion}bar"
6601  *			"in_start"      ^
6602  *			"expr_start"	   ^
6603  *			"expr_end"		 ^
6604  *			"in_end"			    ^
6605  *
6606  * Returns a new allocated string, which the caller must free.
6607  * Returns NULL for failure.
6608  */
6609     static char_u *
6610 make_expanded_name(
6611     char_u	*in_start,
6612     char_u	*expr_start,
6613     char_u	*expr_end,
6614     char_u	*in_end)
6615 {
6616     char_u	c1;
6617     char_u	*retval = NULL;
6618     char_u	*temp_result;
6619     char_u	*nextcmd = NULL;
6620 
6621     if (expr_end == NULL || in_end == NULL)
6622 	return NULL;
6623     *expr_start	= NUL;
6624     *expr_end = NUL;
6625     c1 = *in_end;
6626     *in_end = NUL;
6627 
6628     temp_result = eval_to_string(expr_start + 1, &nextcmd, FALSE);
6629     if (temp_result != NULL && nextcmd == NULL)
6630     {
6631 	retval = alloc((unsigned)(STRLEN(temp_result) + (expr_start - in_start)
6632 						   + (in_end - expr_end) + 1));
6633 	if (retval != NULL)
6634 	{
6635 	    STRCPY(retval, in_start);
6636 	    STRCAT(retval, temp_result);
6637 	    STRCAT(retval, expr_end + 1);
6638 	}
6639     }
6640     vim_free(temp_result);
6641 
6642     *in_end = c1;		/* put char back for error messages */
6643     *expr_start = '{';
6644     *expr_end = '}';
6645 
6646     if (retval != NULL)
6647     {
6648 	temp_result = find_name_end(retval, &expr_start, &expr_end, 0);
6649 	if (expr_start != NULL)
6650 	{
6651 	    /* Further expansion! */
6652 	    temp_result = make_expanded_name(retval, expr_start,
6653 						       expr_end, temp_result);
6654 	    vim_free(retval);
6655 	    retval = temp_result;
6656 	}
6657     }
6658 
6659     return retval;
6660 }
6661 
6662 /*
6663  * Return TRUE if character "c" can be used in a variable or function name.
6664  * Does not include '{' or '}' for magic braces.
6665  */
6666     int
6667 eval_isnamec(int c)
6668 {
6669     return (ASCII_ISALNUM(c) || c == '_' || c == ':' || c == AUTOLOAD_CHAR);
6670 }
6671 
6672 /*
6673  * Return TRUE if character "c" can be used as the first character in a
6674  * variable or function name (excluding '{' and '}').
6675  */
6676     int
6677 eval_isnamec1(int c)
6678 {
6679     return (ASCII_ISALPHA(c) || c == '_');
6680 }
6681 
6682 /*
6683  * Set number v: variable to "val".
6684  */
6685     void
6686 set_vim_var_nr(int idx, varnumber_T val)
6687 {
6688     vimvars[idx].vv_nr = val;
6689 }
6690 
6691 /*
6692  * Get number v: variable value.
6693  */
6694     varnumber_T
6695 get_vim_var_nr(int idx)
6696 {
6697     return vimvars[idx].vv_nr;
6698 }
6699 
6700 /*
6701  * Get string v: variable value.  Uses a static buffer, can only be used once.
6702  * If the String variable has never been set, return an empty string.
6703  * Never returns NULL;
6704  */
6705     char_u *
6706 get_vim_var_str(int idx)
6707 {
6708     return tv_get_string(&vimvars[idx].vv_tv);
6709 }
6710 
6711 /*
6712  * Get List v: variable value.  Caller must take care of reference count when
6713  * needed.
6714  */
6715     list_T *
6716 get_vim_var_list(int idx)
6717 {
6718     return vimvars[idx].vv_list;
6719 }
6720 
6721 /*
6722  * Get Dict v: variable value.  Caller must take care of reference count when
6723  * needed.
6724  */
6725     dict_T *
6726 get_vim_var_dict(int idx)
6727 {
6728     return vimvars[idx].vv_dict;
6729 }
6730 
6731 /*
6732  * Set v:char to character "c".
6733  */
6734     void
6735 set_vim_var_char(int c)
6736 {
6737     char_u	buf[MB_MAXBYTES + 1];
6738 
6739     if (has_mbyte)
6740 	buf[(*mb_char2bytes)(c, buf)] = NUL;
6741     else
6742     {
6743 	buf[0] = c;
6744 	buf[1] = NUL;
6745     }
6746     set_vim_var_string(VV_CHAR, buf, -1);
6747 }
6748 
6749 /*
6750  * Set v:count to "count" and v:count1 to "count1".
6751  * When "set_prevcount" is TRUE first set v:prevcount from v:count.
6752  */
6753     void
6754 set_vcount(
6755     long	count,
6756     long	count1,
6757     int		set_prevcount)
6758 {
6759     if (set_prevcount)
6760 	vimvars[VV_PREVCOUNT].vv_nr = vimvars[VV_COUNT].vv_nr;
6761     vimvars[VV_COUNT].vv_nr = count;
6762     vimvars[VV_COUNT1].vv_nr = count1;
6763 }
6764 
6765 /*
6766  * Save variables that might be changed as a side effect.  Used when executing
6767  * a timer callback.
6768  */
6769     void
6770 save_vimvars(vimvars_save_T *vvsave)
6771 {
6772     vvsave->vv_prevcount = vimvars[VV_PREVCOUNT].vv_nr;
6773     vvsave->vv_count = vimvars[VV_COUNT].vv_nr;
6774     vvsave->vv_count1 = vimvars[VV_COUNT1].vv_nr;
6775 }
6776 
6777 /*
6778  * Restore variables saved by save_vimvars().
6779  */
6780     void
6781 restore_vimvars(vimvars_save_T *vvsave)
6782 {
6783     vimvars[VV_PREVCOUNT].vv_nr = vvsave->vv_prevcount;
6784     vimvars[VV_COUNT].vv_nr = vvsave->vv_count;
6785     vimvars[VV_COUNT1].vv_nr = vvsave->vv_count1;
6786 }
6787 
6788 /*
6789  * Set string v: variable to a copy of "val".
6790  */
6791     void
6792 set_vim_var_string(
6793     int		idx,
6794     char_u	*val,
6795     int		len)	    /* length of "val" to use or -1 (whole string) */
6796 {
6797     clear_tv(&vimvars[idx].vv_di.di_tv);
6798     vimvars[idx].vv_type = VAR_STRING;
6799     if (val == NULL)
6800 	vimvars[idx].vv_str = NULL;
6801     else if (len == -1)
6802 	vimvars[idx].vv_str = vim_strsave(val);
6803     else
6804 	vimvars[idx].vv_str = vim_strnsave(val, len);
6805 }
6806 
6807 /*
6808  * Set List v: variable to "val".
6809  */
6810     void
6811 set_vim_var_list(int idx, list_T *val)
6812 {
6813     clear_tv(&vimvars[idx].vv_di.di_tv);
6814     vimvars[idx].vv_type = VAR_LIST;
6815     vimvars[idx].vv_list = val;
6816     if (val != NULL)
6817 	++val->lv_refcount;
6818 }
6819 
6820 /*
6821  * Set Dictionary v: variable to "val".
6822  */
6823     void
6824 set_vim_var_dict(int idx, dict_T *val)
6825 {
6826     clear_tv(&vimvars[idx].vv_di.di_tv);
6827     vimvars[idx].vv_type = VAR_DICT;
6828     vimvars[idx].vv_dict = val;
6829     if (val != NULL)
6830     {
6831 	++val->dv_refcount;
6832 	dict_set_items_ro(val);
6833     }
6834 }
6835 
6836 /*
6837  * Set v:register if needed.
6838  */
6839     void
6840 set_reg_var(int c)
6841 {
6842     char_u	regname;
6843 
6844     if (c == 0 || c == ' ')
6845 	regname = '"';
6846     else
6847 	regname = c;
6848     /* Avoid free/alloc when the value is already right. */
6849     if (vimvars[VV_REG].vv_str == NULL || vimvars[VV_REG].vv_str[0] != c)
6850 	set_vim_var_string(VV_REG, &regname, 1);
6851 }
6852 
6853 /*
6854  * Get or set v:exception.  If "oldval" == NULL, return the current value.
6855  * Otherwise, restore the value to "oldval" and return NULL.
6856  * Must always be called in pairs to save and restore v:exception!  Does not
6857  * take care of memory allocations.
6858  */
6859     char_u *
6860 v_exception(char_u *oldval)
6861 {
6862     if (oldval == NULL)
6863 	return vimvars[VV_EXCEPTION].vv_str;
6864 
6865     vimvars[VV_EXCEPTION].vv_str = oldval;
6866     return NULL;
6867 }
6868 
6869 /*
6870  * Get or set v:throwpoint.  If "oldval" == NULL, return the current value.
6871  * Otherwise, restore the value to "oldval" and return NULL.
6872  * Must always be called in pairs to save and restore v:throwpoint!  Does not
6873  * take care of memory allocations.
6874  */
6875     char_u *
6876 v_throwpoint(char_u *oldval)
6877 {
6878     if (oldval == NULL)
6879 	return vimvars[VV_THROWPOINT].vv_str;
6880 
6881     vimvars[VV_THROWPOINT].vv_str = oldval;
6882     return NULL;
6883 }
6884 
6885 /*
6886  * Set v:cmdarg.
6887  * If "eap" != NULL, use "eap" to generate the value and return the old value.
6888  * If "oldarg" != NULL, restore the value to "oldarg" and return NULL.
6889  * Must always be called in pairs!
6890  */
6891     char_u *
6892 set_cmdarg(exarg_T *eap, char_u *oldarg)
6893 {
6894     char_u	*oldval;
6895     char_u	*newval;
6896     unsigned	len;
6897 
6898     oldval = vimvars[VV_CMDARG].vv_str;
6899     if (eap == NULL)
6900     {
6901 	vim_free(oldval);
6902 	vimvars[VV_CMDARG].vv_str = oldarg;
6903 	return NULL;
6904     }
6905 
6906     if (eap->force_bin == FORCE_BIN)
6907 	len = 6;
6908     else if (eap->force_bin == FORCE_NOBIN)
6909 	len = 8;
6910     else
6911 	len = 0;
6912 
6913     if (eap->read_edit)
6914 	len += 7;
6915 
6916     if (eap->force_ff != 0)
6917 	len += 10; /* " ++ff=unix" */
6918     if (eap->force_enc != 0)
6919 	len += (unsigned)STRLEN(eap->cmd + eap->force_enc) + 7;
6920     if (eap->bad_char != 0)
6921 	len += 7 + 4;  /* " ++bad=" + "keep" or "drop" */
6922 
6923     newval = alloc(len + 1);
6924     if (newval == NULL)
6925 	return NULL;
6926 
6927     if (eap->force_bin == FORCE_BIN)
6928 	sprintf((char *)newval, " ++bin");
6929     else if (eap->force_bin == FORCE_NOBIN)
6930 	sprintf((char *)newval, " ++nobin");
6931     else
6932 	*newval = NUL;
6933 
6934     if (eap->read_edit)
6935 	STRCAT(newval, " ++edit");
6936 
6937     if (eap->force_ff != 0)
6938 	sprintf((char *)newval + STRLEN(newval), " ++ff=%s",
6939 						eap->force_ff == 'u' ? "unix"
6940 						: eap->force_ff == 'd' ? "dos"
6941 						: "mac");
6942     if (eap->force_enc != 0)
6943 	sprintf((char *)newval + STRLEN(newval), " ++enc=%s",
6944 					       eap->cmd + eap->force_enc);
6945     if (eap->bad_char == BAD_KEEP)
6946 	STRCPY(newval + STRLEN(newval), " ++bad=keep");
6947     else if (eap->bad_char == BAD_DROP)
6948 	STRCPY(newval + STRLEN(newval), " ++bad=drop");
6949     else if (eap->bad_char != 0)
6950 	sprintf((char *)newval + STRLEN(newval), " ++bad=%c", eap->bad_char);
6951     vimvars[VV_CMDARG].vv_str = newval;
6952     return oldval;
6953 }
6954 
6955 /*
6956  * Get the value of internal variable "name".
6957  * Return OK or FAIL.  If OK is returned "rettv" must be cleared.
6958  */
6959     int
6960 get_var_tv(
6961     char_u	*name,
6962     int		len,		/* length of "name" */
6963     typval_T	*rettv,		/* NULL when only checking existence */
6964     dictitem_T	**dip,		/* non-NULL when typval's dict item is needed */
6965     int		verbose,	/* may give error message */
6966     int		no_autoload)	/* do not use script autoloading */
6967 {
6968     int		ret = OK;
6969     typval_T	*tv = NULL;
6970     dictitem_T	*v;
6971     int		cc;
6972 
6973     /* truncate the name, so that we can use strcmp() */
6974     cc = name[len];
6975     name[len] = NUL;
6976 
6977     /*
6978      * Check for user-defined variables.
6979      */
6980     v = find_var(name, NULL, no_autoload);
6981     if (v != NULL)
6982     {
6983 	tv = &v->di_tv;
6984 	if (dip != NULL)
6985 	    *dip = v;
6986     }
6987 
6988     if (tv == NULL)
6989     {
6990 	if (rettv != NULL && verbose)
6991 	    semsg(_(e_undefvar), name);
6992 	ret = FAIL;
6993     }
6994     else if (rettv != NULL)
6995 	copy_tv(tv, rettv);
6996 
6997     name[len] = cc;
6998 
6999     return ret;
7000 }
7001 
7002 /*
7003  * Check if variable "name[len]" is a local variable or an argument.
7004  * If so, "*eval_lavars_used" is set to TRUE.
7005  */
7006     static void
7007 check_vars(char_u *name, int len)
7008 {
7009     int		cc;
7010     char_u	*varname;
7011     hashtab_T	*ht;
7012 
7013     if (eval_lavars_used == NULL)
7014 	return;
7015 
7016     /* truncate the name, so that we can use strcmp() */
7017     cc = name[len];
7018     name[len] = NUL;
7019 
7020     ht = find_var_ht(name, &varname);
7021     if (ht == get_funccal_local_ht() || ht == get_funccal_args_ht())
7022     {
7023 	if (find_var(name, NULL, TRUE) != NULL)
7024 	    *eval_lavars_used = TRUE;
7025     }
7026 
7027     name[len] = cc;
7028 }
7029 
7030 /*
7031  * Handle expr[expr], expr[expr:expr] subscript and .name lookup.
7032  * Also handle function call with Funcref variable: func(expr)
7033  * Can all be combined: dict.func(expr)[idx]['func'](expr)
7034  */
7035     int
7036 handle_subscript(
7037     char_u	**arg,
7038     typval_T	*rettv,
7039     int		evaluate,	/* do more than finding the end */
7040     int		verbose)	/* give error messages */
7041 {
7042     int		ret = OK;
7043     dict_T	*selfdict = NULL;
7044     char_u	*s;
7045     int		len;
7046     typval_T	functv;
7047 
7048     while (ret == OK
7049 	    && (**arg == '['
7050 		|| (**arg == '.' && rettv->v_type == VAR_DICT)
7051 		|| (**arg == '(' && (!evaluate || rettv->v_type == VAR_FUNC
7052 					    || rettv->v_type == VAR_PARTIAL)))
7053 	    && !VIM_ISWHITE(*(*arg - 1)))
7054     {
7055 	if (**arg == '(')
7056 	{
7057 	    partial_T	*pt = NULL;
7058 
7059 	    /* need to copy the funcref so that we can clear rettv */
7060 	    if (evaluate)
7061 	    {
7062 		functv = *rettv;
7063 		rettv->v_type = VAR_UNKNOWN;
7064 
7065 		/* Invoke the function.  Recursive! */
7066 		if (functv.v_type == VAR_PARTIAL)
7067 		{
7068 		    pt = functv.vval.v_partial;
7069 		    s = partial_name(pt);
7070 		}
7071 		else
7072 		    s = functv.vval.v_string;
7073 	    }
7074 	    else
7075 		s = (char_u *)"";
7076 	    ret = get_func_tv(s, (int)STRLEN(s), rettv, arg,
7077 			curwin->w_cursor.lnum, curwin->w_cursor.lnum,
7078 			&len, evaluate, pt, selfdict);
7079 
7080 	    /* Clear the funcref afterwards, so that deleting it while
7081 	     * evaluating the arguments is possible (see test55). */
7082 	    if (evaluate)
7083 		clear_tv(&functv);
7084 
7085 	    /* Stop the expression evaluation when immediately aborting on
7086 	     * error, or when an interrupt occurred or an exception was thrown
7087 	     * but not caught. */
7088 	    if (aborting())
7089 	    {
7090 		if (ret == OK)
7091 		    clear_tv(rettv);
7092 		ret = FAIL;
7093 	    }
7094 	    dict_unref(selfdict);
7095 	    selfdict = NULL;
7096 	}
7097 	else /* **arg == '[' || **arg == '.' */
7098 	{
7099 	    dict_unref(selfdict);
7100 	    if (rettv->v_type == VAR_DICT)
7101 	    {
7102 		selfdict = rettv->vval.v_dict;
7103 		if (selfdict != NULL)
7104 		    ++selfdict->dv_refcount;
7105 	    }
7106 	    else
7107 		selfdict = NULL;
7108 	    if (eval_index(arg, rettv, evaluate, verbose) == FAIL)
7109 	    {
7110 		clear_tv(rettv);
7111 		ret = FAIL;
7112 	    }
7113 	}
7114     }
7115 
7116     /* Turn "dict.Func" into a partial for "Func" bound to "dict".
7117      * Don't do this when "Func" is already a partial that was bound
7118      * explicitly (pt_auto is FALSE). */
7119     if (selfdict != NULL
7120 	    && (rettv->v_type == VAR_FUNC
7121 		|| (rettv->v_type == VAR_PARTIAL
7122 		    && (rettv->vval.v_partial->pt_auto
7123 			|| rettv->vval.v_partial->pt_dict == NULL))))
7124 	selfdict = make_partial(selfdict, rettv);
7125 
7126     dict_unref(selfdict);
7127     return ret;
7128 }
7129 
7130 /*
7131  * Allocate memory for a variable type-value, and make it empty (0 or NULL
7132  * value).
7133  */
7134     typval_T *
7135 alloc_tv(void)
7136 {
7137     return (typval_T *)alloc_clear((unsigned)sizeof(typval_T));
7138 }
7139 
7140 /*
7141  * Allocate memory for a variable type-value, and assign a string to it.
7142  * The string "s" must have been allocated, it is consumed.
7143  * Return NULL for out of memory, the variable otherwise.
7144  */
7145     static typval_T *
7146 alloc_string_tv(char_u *s)
7147 {
7148     typval_T	*rettv;
7149 
7150     rettv = alloc_tv();
7151     if (rettv != NULL)
7152     {
7153 	rettv->v_type = VAR_STRING;
7154 	rettv->vval.v_string = s;
7155     }
7156     else
7157 	vim_free(s);
7158     return rettv;
7159 }
7160 
7161 /*
7162  * Free the memory for a variable type-value.
7163  */
7164     void
7165 free_tv(typval_T *varp)
7166 {
7167     if (varp != NULL)
7168     {
7169 	switch (varp->v_type)
7170 	{
7171 	    case VAR_FUNC:
7172 		func_unref(varp->vval.v_string);
7173 		/* FALLTHROUGH */
7174 	    case VAR_STRING:
7175 		vim_free(varp->vval.v_string);
7176 		break;
7177 	    case VAR_PARTIAL:
7178 		partial_unref(varp->vval.v_partial);
7179 		break;
7180 	    case VAR_BLOB:
7181 		blob_unref(varp->vval.v_blob);
7182 		break;
7183 	    case VAR_LIST:
7184 		list_unref(varp->vval.v_list);
7185 		break;
7186 	    case VAR_DICT:
7187 		dict_unref(varp->vval.v_dict);
7188 		break;
7189 	    case VAR_JOB:
7190 #ifdef FEAT_JOB_CHANNEL
7191 		job_unref(varp->vval.v_job);
7192 		break;
7193 #endif
7194 	    case VAR_CHANNEL:
7195 #ifdef FEAT_JOB_CHANNEL
7196 		channel_unref(varp->vval.v_channel);
7197 		break;
7198 #endif
7199 	    case VAR_NUMBER:
7200 	    case VAR_FLOAT:
7201 	    case VAR_UNKNOWN:
7202 	    case VAR_SPECIAL:
7203 		break;
7204 	}
7205 	vim_free(varp);
7206     }
7207 }
7208 
7209 /*
7210  * Free the memory for a variable value and set the value to NULL or 0.
7211  */
7212     void
7213 clear_tv(typval_T *varp)
7214 {
7215     if (varp != NULL)
7216     {
7217 	switch (varp->v_type)
7218 	{
7219 	    case VAR_FUNC:
7220 		func_unref(varp->vval.v_string);
7221 		/* FALLTHROUGH */
7222 	    case VAR_STRING:
7223 		VIM_CLEAR(varp->vval.v_string);
7224 		break;
7225 	    case VAR_PARTIAL:
7226 		partial_unref(varp->vval.v_partial);
7227 		varp->vval.v_partial = NULL;
7228 		break;
7229 	    case VAR_BLOB:
7230 		blob_unref(varp->vval.v_blob);
7231 		varp->vval.v_blob = NULL;
7232 		break;
7233 	    case VAR_LIST:
7234 		list_unref(varp->vval.v_list);
7235 		varp->vval.v_list = NULL;
7236 		break;
7237 	    case VAR_DICT:
7238 		dict_unref(varp->vval.v_dict);
7239 		varp->vval.v_dict = NULL;
7240 		break;
7241 	    case VAR_NUMBER:
7242 	    case VAR_SPECIAL:
7243 		varp->vval.v_number = 0;
7244 		break;
7245 	    case VAR_FLOAT:
7246 #ifdef FEAT_FLOAT
7247 		varp->vval.v_float = 0.0;
7248 		break;
7249 #endif
7250 	    case VAR_JOB:
7251 #ifdef FEAT_JOB_CHANNEL
7252 		job_unref(varp->vval.v_job);
7253 		varp->vval.v_job = NULL;
7254 #endif
7255 		break;
7256 	    case VAR_CHANNEL:
7257 #ifdef FEAT_JOB_CHANNEL
7258 		channel_unref(varp->vval.v_channel);
7259 		varp->vval.v_channel = NULL;
7260 #endif
7261 	    case VAR_UNKNOWN:
7262 		break;
7263 	}
7264 	varp->v_lock = 0;
7265     }
7266 }
7267 
7268 /*
7269  * Set the value of a variable to NULL without freeing items.
7270  */
7271     void
7272 init_tv(typval_T *varp)
7273 {
7274     if (varp != NULL)
7275 	vim_memset(varp, 0, sizeof(typval_T));
7276 }
7277 
7278 /*
7279  * Get the number value of a variable.
7280  * If it is a String variable, uses vim_str2nr().
7281  * For incompatible types, return 0.
7282  * tv_get_number_chk() is similar to tv_get_number(), but informs the
7283  * caller of incompatible types: it sets *denote to TRUE if "denote"
7284  * is not NULL or returns -1 otherwise.
7285  */
7286     varnumber_T
7287 tv_get_number(typval_T *varp)
7288 {
7289     int		error = FALSE;
7290 
7291     return tv_get_number_chk(varp, &error);	/* return 0L on error */
7292 }
7293 
7294     varnumber_T
7295 tv_get_number_chk(typval_T *varp, int *denote)
7296 {
7297     varnumber_T	n = 0L;
7298 
7299     switch (varp->v_type)
7300     {
7301 	case VAR_NUMBER:
7302 	    return varp->vval.v_number;
7303 	case VAR_FLOAT:
7304 #ifdef FEAT_FLOAT
7305 	    emsg(_("E805: Using a Float as a Number"));
7306 	    break;
7307 #endif
7308 	case VAR_FUNC:
7309 	case VAR_PARTIAL:
7310 	    emsg(_("E703: Using a Funcref as a Number"));
7311 	    break;
7312 	case VAR_STRING:
7313 	    if (varp->vval.v_string != NULL)
7314 		vim_str2nr(varp->vval.v_string, NULL, NULL,
7315 						    STR2NR_ALL, &n, NULL, 0);
7316 	    return n;
7317 	case VAR_LIST:
7318 	    emsg(_("E745: Using a List as a Number"));
7319 	    break;
7320 	case VAR_DICT:
7321 	    emsg(_("E728: Using a Dictionary as a Number"));
7322 	    break;
7323 	case VAR_SPECIAL:
7324 	    return varp->vval.v_number == VVAL_TRUE ? 1 : 0;
7325 	    break;
7326 	case VAR_JOB:
7327 #ifdef FEAT_JOB_CHANNEL
7328 	    emsg(_("E910: Using a Job as a Number"));
7329 	    break;
7330 #endif
7331 	case VAR_CHANNEL:
7332 #ifdef FEAT_JOB_CHANNEL
7333 	    emsg(_("E913: Using a Channel as a Number"));
7334 	    break;
7335 #endif
7336 	case VAR_BLOB:
7337 	    emsg(_("E974: Using a Blob as a Number"));
7338 	    break;
7339 	case VAR_UNKNOWN:
7340 	    internal_error("tv_get_number(UNKNOWN)");
7341 	    break;
7342     }
7343     if (denote == NULL)		/* useful for values that must be unsigned */
7344 	n = -1;
7345     else
7346 	*denote = TRUE;
7347     return n;
7348 }
7349 
7350 #ifdef FEAT_FLOAT
7351     float_T
7352 tv_get_float(typval_T *varp)
7353 {
7354     switch (varp->v_type)
7355     {
7356 	case VAR_NUMBER:
7357 	    return (float_T)(varp->vval.v_number);
7358 	case VAR_FLOAT:
7359 	    return varp->vval.v_float;
7360 	case VAR_FUNC:
7361 	case VAR_PARTIAL:
7362 	    emsg(_("E891: Using a Funcref as a Float"));
7363 	    break;
7364 	case VAR_STRING:
7365 	    emsg(_("E892: Using a String as a Float"));
7366 	    break;
7367 	case VAR_LIST:
7368 	    emsg(_("E893: Using a List as a Float"));
7369 	    break;
7370 	case VAR_DICT:
7371 	    emsg(_("E894: Using a Dictionary as a Float"));
7372 	    break;
7373 	case VAR_SPECIAL:
7374 	    emsg(_("E907: Using a special value as a Float"));
7375 	    break;
7376 	case VAR_JOB:
7377 # ifdef FEAT_JOB_CHANNEL
7378 	    emsg(_("E911: Using a Job as a Float"));
7379 	    break;
7380 # endif
7381 	case VAR_CHANNEL:
7382 # ifdef FEAT_JOB_CHANNEL
7383 	    emsg(_("E914: Using a Channel as a Float"));
7384 	    break;
7385 # endif
7386 	case VAR_BLOB:
7387 	    emsg(_("E975: Using a Blob as a Float"));
7388 	    break;
7389 	case VAR_UNKNOWN:
7390 	    internal_error("tv_get_float(UNKNOWN)");
7391 	    break;
7392     }
7393     return 0;
7394 }
7395 #endif
7396 
7397 /*
7398  * Get the string value of a variable.
7399  * If it is a Number variable, the number is converted into a string.
7400  * tv_get_string() uses a single, static buffer.  YOU CAN ONLY USE IT ONCE!
7401  * tv_get_string_buf() uses a given buffer.
7402  * If the String variable has never been set, return an empty string.
7403  * Never returns NULL;
7404  * tv_get_string_chk() and tv_get_string_buf_chk() are similar, but return
7405  * NULL on error.
7406  */
7407     char_u *
7408 tv_get_string(typval_T *varp)
7409 {
7410     static char_u   mybuf[NUMBUFLEN];
7411 
7412     return tv_get_string_buf(varp, mybuf);
7413 }
7414 
7415     char_u *
7416 tv_get_string_buf(typval_T *varp, char_u *buf)
7417 {
7418     char_u	*res =  tv_get_string_buf_chk(varp, buf);
7419 
7420     return res != NULL ? res : (char_u *)"";
7421 }
7422 
7423 /*
7424  * Careful: This uses a single, static buffer.  YOU CAN ONLY USE IT ONCE!
7425  */
7426     char_u *
7427 tv_get_string_chk(typval_T *varp)
7428 {
7429     static char_u   mybuf[NUMBUFLEN];
7430 
7431     return tv_get_string_buf_chk(varp, mybuf);
7432 }
7433 
7434     char_u *
7435 tv_get_string_buf_chk(typval_T *varp, char_u *buf)
7436 {
7437     switch (varp->v_type)
7438     {
7439 	case VAR_NUMBER:
7440 	    vim_snprintf((char *)buf, NUMBUFLEN, "%lld",
7441 					    (long_long_T)varp->vval.v_number);
7442 	    return buf;
7443 	case VAR_FUNC:
7444 	case VAR_PARTIAL:
7445 	    emsg(_("E729: using Funcref as a String"));
7446 	    break;
7447 	case VAR_LIST:
7448 	    emsg(_("E730: using List as a String"));
7449 	    break;
7450 	case VAR_DICT:
7451 	    emsg(_("E731: using Dictionary as a String"));
7452 	    break;
7453 	case VAR_FLOAT:
7454 #ifdef FEAT_FLOAT
7455 	    emsg(_(e_float_as_string));
7456 	    break;
7457 #endif
7458 	case VAR_STRING:
7459 	    if (varp->vval.v_string != NULL)
7460 		return varp->vval.v_string;
7461 	    return (char_u *)"";
7462 	case VAR_SPECIAL:
7463 	    STRCPY(buf, get_var_special_name(varp->vval.v_number));
7464 	    return buf;
7465         case VAR_BLOB:
7466 	    emsg(_("E976: using Blob as a String"));
7467 	    break;
7468 	case VAR_JOB:
7469 #ifdef FEAT_JOB_CHANNEL
7470 	    {
7471 		job_T *job = varp->vval.v_job;
7472 		char  *status;
7473 
7474 		if (job == NULL)
7475 		    return (char_u *)"no process";
7476 		status = job->jv_status == JOB_FAILED ? "fail"
7477 				: job->jv_status >= JOB_ENDED ? "dead"
7478 				: "run";
7479 # ifdef UNIX
7480 		vim_snprintf((char *)buf, NUMBUFLEN,
7481 			    "process %ld %s", (long)job->jv_pid, status);
7482 # elif defined(MSWIN)
7483 		vim_snprintf((char *)buf, NUMBUFLEN,
7484 			    "process %ld %s",
7485 			    (long)job->jv_proc_info.dwProcessId,
7486 			    status);
7487 # else
7488 		/* fall-back */
7489 		vim_snprintf((char *)buf, NUMBUFLEN, "process ? %s", status);
7490 # endif
7491 		return buf;
7492 	    }
7493 #endif
7494 	    break;
7495 	case VAR_CHANNEL:
7496 #ifdef FEAT_JOB_CHANNEL
7497 	    {
7498 		channel_T *channel = varp->vval.v_channel;
7499 		char      *status = channel_status(channel, -1);
7500 
7501 		if (channel == NULL)
7502 		    vim_snprintf((char *)buf, NUMBUFLEN, "channel %s", status);
7503 		else
7504 		    vim_snprintf((char *)buf, NUMBUFLEN,
7505 				     "channel %d %s", channel->ch_id, status);
7506 		return buf;
7507 	    }
7508 #endif
7509 	    break;
7510 	case VAR_UNKNOWN:
7511 	    emsg(_("E908: using an invalid value as a String"));
7512 	    break;
7513     }
7514     return NULL;
7515 }
7516 
7517 /*
7518  * Turn a typeval into a string.  Similar to tv_get_string_buf() but uses
7519  * string() on Dict, List, etc.
7520  */
7521     char_u *
7522 tv_stringify(typval_T *varp, char_u *buf)
7523 {
7524     if (varp->v_type == VAR_LIST
7525 	    || varp->v_type == VAR_DICT
7526 	    || varp->v_type == VAR_FUNC
7527 	    || varp->v_type == VAR_PARTIAL
7528 	    || varp->v_type == VAR_FLOAT)
7529     {
7530 	typval_T tmp;
7531 
7532 	f_string(varp, &tmp);
7533 	tv_get_string_buf(&tmp, buf);
7534 	clear_tv(varp);
7535 	*varp = tmp;
7536 	return tmp.vval.v_string;
7537     }
7538     return tv_get_string_buf(varp, buf);
7539 }
7540 
7541 /*
7542  * Find variable "name" in the list of variables.
7543  * Return a pointer to it if found, NULL if not found.
7544  * Careful: "a:0" variables don't have a name.
7545  * When "htp" is not NULL we are writing to the variable, set "htp" to the
7546  * hashtab_T used.
7547  */
7548     dictitem_T *
7549 find_var(char_u *name, hashtab_T **htp, int no_autoload)
7550 {
7551     char_u	*varname;
7552     hashtab_T	*ht;
7553     dictitem_T	*ret = NULL;
7554 
7555     ht = find_var_ht(name, &varname);
7556     if (htp != NULL)
7557 	*htp = ht;
7558     if (ht == NULL)
7559 	return NULL;
7560     ret = find_var_in_ht(ht, *name, varname, no_autoload || htp != NULL);
7561     if (ret != NULL)
7562 	return ret;
7563 
7564     /* Search in parent scope for lambda */
7565     return find_var_in_scoped_ht(name, no_autoload || htp != NULL);
7566 }
7567 
7568 /*
7569  * Find variable "varname" in hashtab "ht" with name "htname".
7570  * Returns NULL if not found.
7571  */
7572     dictitem_T *
7573 find_var_in_ht(
7574     hashtab_T	*ht,
7575     int		htname,
7576     char_u	*varname,
7577     int		no_autoload)
7578 {
7579     hashitem_T	*hi;
7580 
7581     if (*varname == NUL)
7582     {
7583 	/* Must be something like "s:", otherwise "ht" would be NULL. */
7584 	switch (htname)
7585 	{
7586 	    case 's': return &SCRIPT_SV(current_sctx.sc_sid)->sv_var;
7587 	    case 'g': return &globvars_var;
7588 	    case 'v': return &vimvars_var;
7589 	    case 'b': return &curbuf->b_bufvar;
7590 	    case 'w': return &curwin->w_winvar;
7591 	    case 't': return &curtab->tp_winvar;
7592 	    case 'l': return get_funccal_local_var();
7593 	    case 'a': return get_funccal_args_var();
7594 	}
7595 	return NULL;
7596     }
7597 
7598     hi = hash_find(ht, varname);
7599     if (HASHITEM_EMPTY(hi))
7600     {
7601 	/* For global variables we may try auto-loading the script.  If it
7602 	 * worked find the variable again.  Don't auto-load a script if it was
7603 	 * loaded already, otherwise it would be loaded every time when
7604 	 * checking if a function name is a Funcref variable. */
7605 	if (ht == &globvarht && !no_autoload)
7606 	{
7607 	    /* Note: script_autoload() may make "hi" invalid. It must either
7608 	     * be obtained again or not used. */
7609 	    if (!script_autoload(varname, FALSE) || aborting())
7610 		return NULL;
7611 	    hi = hash_find(ht, varname);
7612 	}
7613 	if (HASHITEM_EMPTY(hi))
7614 	    return NULL;
7615     }
7616     return HI2DI(hi);
7617 }
7618 
7619 /*
7620  * Find the hashtab used for a variable name.
7621  * Return NULL if the name is not valid.
7622  * Set "varname" to the start of name without ':'.
7623  */
7624     hashtab_T *
7625 find_var_ht(char_u *name, char_u **varname)
7626 {
7627     hashitem_T	*hi;
7628     hashtab_T	*ht;
7629 
7630     if (name[0] == NUL)
7631 	return NULL;
7632     if (name[1] != ':')
7633     {
7634 	/* The name must not start with a colon or #. */
7635 	if (name[0] == ':' || name[0] == AUTOLOAD_CHAR)
7636 	    return NULL;
7637 	*varname = name;
7638 
7639 	/* "version" is "v:version" in all scopes */
7640 	hi = hash_find(&compat_hashtab, name);
7641 	if (!HASHITEM_EMPTY(hi))
7642 	    return &compat_hashtab;
7643 
7644 	ht = get_funccal_local_ht();
7645 	if (ht == NULL)
7646 	    return &globvarht;			/* global variable */
7647 	return ht;				/* local variable */
7648     }
7649     *varname = name + 2;
7650     if (*name == 'g')				/* global variable */
7651 	return &globvarht;
7652     /* There must be no ':' or '#' in the rest of the name, unless g: is used
7653      */
7654     if (vim_strchr(name + 2, ':') != NULL
7655 			       || vim_strchr(name + 2, AUTOLOAD_CHAR) != NULL)
7656 	return NULL;
7657     if (*name == 'b')				/* buffer variable */
7658 	return &curbuf->b_vars->dv_hashtab;
7659     if (*name == 'w')				/* window variable */
7660 	return &curwin->w_vars->dv_hashtab;
7661     if (*name == 't')				/* tab page variable */
7662 	return &curtab->tp_vars->dv_hashtab;
7663     if (*name == 'v')				/* v: variable */
7664 	return &vimvarht;
7665     if (*name == 'a')				/* a: function argument */
7666 	return get_funccal_args_ht();
7667     if (*name == 'l')				/* l: local function variable */
7668 	return get_funccal_local_ht();
7669     if (*name == 's'				/* script variable */
7670 	    && current_sctx.sc_sid > 0 && current_sctx.sc_sid <= ga_scripts.ga_len)
7671 	return &SCRIPT_VARS(current_sctx.sc_sid);
7672     return NULL;
7673 }
7674 
7675 /*
7676  * Get the string value of a (global/local) variable.
7677  * Note: see tv_get_string() for how long the pointer remains valid.
7678  * Returns NULL when it doesn't exist.
7679  */
7680     char_u *
7681 get_var_value(char_u *name)
7682 {
7683     dictitem_T	*v;
7684 
7685     v = find_var(name, NULL, FALSE);
7686     if (v == NULL)
7687 	return NULL;
7688     return tv_get_string(&v->di_tv);
7689 }
7690 
7691 /*
7692  * Allocate a new hashtab for a sourced script.  It will be used while
7693  * sourcing this script and when executing functions defined in the script.
7694  */
7695     void
7696 new_script_vars(scid_T id)
7697 {
7698     int		i;
7699     hashtab_T	*ht;
7700     scriptvar_T *sv;
7701 
7702     if (ga_grow(&ga_scripts, (int)(id - ga_scripts.ga_len)) == OK)
7703     {
7704 	/* Re-allocating ga_data means that an ht_array pointing to
7705 	 * ht_smallarray becomes invalid.  We can recognize this: ht_mask is
7706 	 * at its init value.  Also reset "v_dict", it's always the same. */
7707 	for (i = 1; i <= ga_scripts.ga_len; ++i)
7708 	{
7709 	    ht = &SCRIPT_VARS(i);
7710 	    if (ht->ht_mask == HT_INIT_SIZE - 1)
7711 		ht->ht_array = ht->ht_smallarray;
7712 	    sv = SCRIPT_SV(i);
7713 	    sv->sv_var.di_tv.vval.v_dict = &sv->sv_dict;
7714 	}
7715 
7716 	while (ga_scripts.ga_len < id)
7717 	{
7718 	    sv = SCRIPT_SV(ga_scripts.ga_len + 1) =
7719 		(scriptvar_T *)alloc_clear(sizeof(scriptvar_T));
7720 	    init_var_dict(&sv->sv_dict, &sv->sv_var, VAR_SCOPE);
7721 	    ++ga_scripts.ga_len;
7722 	}
7723     }
7724 }
7725 
7726 /*
7727  * Initialize dictionary "dict" as a scope and set variable "dict_var" to
7728  * point to it.
7729  */
7730     void
7731 init_var_dict(dict_T *dict, dictitem_T *dict_var, int scope)
7732 {
7733     hash_init(&dict->dv_hashtab);
7734     dict->dv_lock = 0;
7735     dict->dv_scope = scope;
7736     dict->dv_refcount = DO_NOT_FREE_CNT;
7737     dict->dv_copyID = 0;
7738     dict_var->di_tv.vval.v_dict = dict;
7739     dict_var->di_tv.v_type = VAR_DICT;
7740     dict_var->di_tv.v_lock = VAR_FIXED;
7741     dict_var->di_flags = DI_FLAGS_RO | DI_FLAGS_FIX;
7742     dict_var->di_key[0] = NUL;
7743 }
7744 
7745 /*
7746  * Unreference a dictionary initialized by init_var_dict().
7747  */
7748     void
7749 unref_var_dict(dict_T *dict)
7750 {
7751     /* Now the dict needs to be freed if no one else is using it, go back to
7752      * normal reference counting. */
7753     dict->dv_refcount -= DO_NOT_FREE_CNT - 1;
7754     dict_unref(dict);
7755 }
7756 
7757 /*
7758  * Clean up a list of internal variables.
7759  * Frees all allocated variables and the value they contain.
7760  * Clears hashtab "ht", does not free it.
7761  */
7762     void
7763 vars_clear(hashtab_T *ht)
7764 {
7765     vars_clear_ext(ht, TRUE);
7766 }
7767 
7768 /*
7769  * Like vars_clear(), but only free the value if "free_val" is TRUE.
7770  */
7771     void
7772 vars_clear_ext(hashtab_T *ht, int free_val)
7773 {
7774     int		todo;
7775     hashitem_T	*hi;
7776     dictitem_T	*v;
7777 
7778     hash_lock(ht);
7779     todo = (int)ht->ht_used;
7780     for (hi = ht->ht_array; todo > 0; ++hi)
7781     {
7782 	if (!HASHITEM_EMPTY(hi))
7783 	{
7784 	    --todo;
7785 
7786 	    /* Free the variable.  Don't remove it from the hashtab,
7787 	     * ht_array might change then.  hash_clear() takes care of it
7788 	     * later. */
7789 	    v = HI2DI(hi);
7790 	    if (free_val)
7791 		clear_tv(&v->di_tv);
7792 	    if (v->di_flags & DI_FLAGS_ALLOC)
7793 		vim_free(v);
7794 	}
7795     }
7796     hash_clear(ht);
7797     ht->ht_used = 0;
7798 }
7799 
7800 /*
7801  * Delete a variable from hashtab "ht" at item "hi".
7802  * Clear the variable value and free the dictitem.
7803  */
7804     static void
7805 delete_var(hashtab_T *ht, hashitem_T *hi)
7806 {
7807     dictitem_T	*di = HI2DI(hi);
7808 
7809     hash_remove(ht, hi);
7810     clear_tv(&di->di_tv);
7811     vim_free(di);
7812 }
7813 
7814 /*
7815  * List the value of one internal variable.
7816  */
7817     static void
7818 list_one_var(dictitem_T *v, char *prefix, int *first)
7819 {
7820     char_u	*tofree;
7821     char_u	*s;
7822     char_u	numbuf[NUMBUFLEN];
7823 
7824     s = echo_string(&v->di_tv, &tofree, numbuf, get_copyID());
7825     list_one_var_a(prefix, v->di_key, v->di_tv.v_type,
7826 					 s == NULL ? (char_u *)"" : s, first);
7827     vim_free(tofree);
7828 }
7829 
7830     static void
7831 list_one_var_a(
7832     char	*prefix,
7833     char_u	*name,
7834     int		type,
7835     char_u	*string,
7836     int		*first)  /* when TRUE clear rest of screen and set to FALSE */
7837 {
7838     /* don't use msg() or msg_attr() to avoid overwriting "v:statusmsg" */
7839     msg_start();
7840     msg_puts(prefix);
7841     if (name != NULL)	/* "a:" vars don't have a name stored */
7842 	msg_puts((char *)name);
7843     msg_putchar(' ');
7844     msg_advance(22);
7845     if (type == VAR_NUMBER)
7846 	msg_putchar('#');
7847     else if (type == VAR_FUNC || type == VAR_PARTIAL)
7848 	msg_putchar('*');
7849     else if (type == VAR_LIST)
7850     {
7851 	msg_putchar('[');
7852 	if (*string == '[')
7853 	    ++string;
7854     }
7855     else if (type == VAR_DICT)
7856     {
7857 	msg_putchar('{');
7858 	if (*string == '{')
7859 	    ++string;
7860     }
7861     else
7862 	msg_putchar(' ');
7863 
7864     msg_outtrans(string);
7865 
7866     if (type == VAR_FUNC || type == VAR_PARTIAL)
7867 	msg_puts("()");
7868     if (*first)
7869     {
7870 	msg_clr_eos();
7871 	*first = FALSE;
7872     }
7873 }
7874 
7875 /*
7876  * Set variable "name" to value in "tv".
7877  * If the variable already exists, the value is updated.
7878  * Otherwise the variable is created.
7879  */
7880     void
7881 set_var(
7882     char_u	*name,
7883     typval_T	*tv,
7884     int		copy)	    /* make copy of value in "tv" */
7885 {
7886     dictitem_T	*v;
7887     char_u	*varname;
7888     hashtab_T	*ht;
7889 
7890     ht = find_var_ht(name, &varname);
7891     if (ht == NULL || *varname == NUL)
7892     {
7893 	semsg(_(e_illvar), name);
7894 	return;
7895     }
7896     v = find_var_in_ht(ht, 0, varname, TRUE);
7897 
7898     /* Search in parent scope which is possible to reference from lambda */
7899     if (v == NULL)
7900 	v = find_var_in_scoped_ht(name, TRUE);
7901 
7902     if ((tv->v_type == VAR_FUNC || tv->v_type == VAR_PARTIAL)
7903 				      && var_check_func_name(name, v == NULL))
7904 	return;
7905 
7906     if (v != NULL)
7907     {
7908 	/* existing variable, need to clear the value */
7909 	if (var_check_ro(v->di_flags, name, FALSE)
7910 			      || var_check_lock(v->di_tv.v_lock, name, FALSE))
7911 	    return;
7912 
7913 	/*
7914 	 * Handle setting internal v: variables separately where needed to
7915 	 * prevent changing the type.
7916 	 */
7917 	if (ht == &vimvarht)
7918 	{
7919 	    if (v->di_tv.v_type == VAR_STRING)
7920 	    {
7921 		VIM_CLEAR(v->di_tv.vval.v_string);
7922 		if (copy || tv->v_type != VAR_STRING)
7923 		{
7924 		    char_u *val = tv_get_string(tv);
7925 
7926 		    // Careful: when assigning to v:errmsg and tv_get_string()
7927 		    // causes an error message the variable will alrady be set.
7928 		    if (v->di_tv.vval.v_string == NULL)
7929 			v->di_tv.vval.v_string = vim_strsave(val);
7930 		}
7931 		else
7932 		{
7933 		    /* Take over the string to avoid an extra alloc/free. */
7934 		    v->di_tv.vval.v_string = tv->vval.v_string;
7935 		    tv->vval.v_string = NULL;
7936 		}
7937 		return;
7938 	    }
7939 	    else if (v->di_tv.v_type == VAR_NUMBER)
7940 	    {
7941 		v->di_tv.vval.v_number = tv_get_number(tv);
7942 		if (STRCMP(varname, "searchforward") == 0)
7943 		    set_search_direction(v->di_tv.vval.v_number ? '/' : '?');
7944 #ifdef FEAT_SEARCH_EXTRA
7945 		else if (STRCMP(varname, "hlsearch") == 0)
7946 		{
7947 		    no_hlsearch = !v->di_tv.vval.v_number;
7948 		    redraw_all_later(SOME_VALID);
7949 		}
7950 #endif
7951 		return;
7952 	    }
7953 	    else if (v->di_tv.v_type != tv->v_type)
7954 	    {
7955 		semsg(_("E963: setting %s to value with wrong type"), name);
7956 		return;
7957 	    }
7958 	}
7959 
7960 	clear_tv(&v->di_tv);
7961     }
7962     else		    /* add a new variable */
7963     {
7964 	// Can't add "v:" or "a:" variable.
7965 	if (ht == &vimvarht || ht == get_funccal_args_ht())
7966 	{
7967 	    semsg(_(e_illvar), name);
7968 	    return;
7969 	}
7970 
7971 	// Make sure the variable name is valid.
7972 	if (!valid_varname(varname))
7973 	    return;
7974 
7975 	v = (dictitem_T *)alloc((unsigned)(sizeof(dictitem_T)
7976 							  + STRLEN(varname)));
7977 	if (v == NULL)
7978 	    return;
7979 	STRCPY(v->di_key, varname);
7980 	if (hash_add(ht, DI2HIKEY(v)) == FAIL)
7981 	{
7982 	    vim_free(v);
7983 	    return;
7984 	}
7985 	v->di_flags = DI_FLAGS_ALLOC;
7986     }
7987 
7988     if (copy || tv->v_type == VAR_NUMBER || tv->v_type == VAR_FLOAT)
7989 	copy_tv(tv, &v->di_tv);
7990     else
7991     {
7992 	v->di_tv = *tv;
7993 	v->di_tv.v_lock = 0;
7994 	init_tv(tv);
7995     }
7996 }
7997 
7998 /*
7999  * Return TRUE if di_flags "flags" indicates variable "name" is read-only.
8000  * Also give an error message.
8001  */
8002     int
8003 var_check_ro(int flags, char_u *name, int use_gettext)
8004 {
8005     if (flags & DI_FLAGS_RO)
8006     {
8007 	semsg(_(e_readonlyvar), use_gettext ? (char_u *)_(name) : name);
8008 	return TRUE;
8009     }
8010     if ((flags & DI_FLAGS_RO_SBX) && sandbox)
8011     {
8012 	semsg(_(e_readonlysbx), use_gettext ? (char_u *)_(name) : name);
8013 	return TRUE;
8014     }
8015     return FALSE;
8016 }
8017 
8018 /*
8019  * Return TRUE if di_flags "flags" indicates variable "name" is fixed.
8020  * Also give an error message.
8021  */
8022     int
8023 var_check_fixed(int flags, char_u *name, int use_gettext)
8024 {
8025     if (flags & DI_FLAGS_FIX)
8026     {
8027 	semsg(_("E795: Cannot delete variable %s"),
8028 				      use_gettext ? (char_u *)_(name) : name);
8029 	return TRUE;
8030     }
8031     return FALSE;
8032 }
8033 
8034 /*
8035  * Check if a funcref is assigned to a valid variable name.
8036  * Return TRUE and give an error if not.
8037  */
8038     int
8039 var_check_func_name(
8040     char_u *name,    /* points to start of variable name */
8041     int    new_var)  /* TRUE when creating the variable */
8042 {
8043     /* Allow for w: b: s: and t:. */
8044     if (!(vim_strchr((char_u *)"wbst", name[0]) != NULL && name[1] == ':')
8045 	    && !ASCII_ISUPPER((name[0] != NUL && name[1] == ':')
8046 						     ? name[2] : name[0]))
8047     {
8048 	semsg(_("E704: Funcref variable name must start with a capital: %s"),
8049 									name);
8050 	return TRUE;
8051     }
8052     /* Don't allow hiding a function.  When "v" is not NULL we might be
8053      * assigning another function to the same var, the type is checked
8054      * below. */
8055     if (new_var && function_exists(name, FALSE))
8056     {
8057 	semsg(_("E705: Variable name conflicts with existing function: %s"),
8058 								    name);
8059 	return TRUE;
8060     }
8061     return FALSE;
8062 }
8063 
8064 /*
8065  * Return TRUE if "flags" indicates variable "name" is locked (immutable).
8066  * Also give an error message, using "name" or _("name") when use_gettext is
8067  * TRUE.
8068  */
8069     int
8070 var_check_lock(int lock, char_u *name, int use_gettext)
8071 {
8072     if (lock & VAR_LOCKED)
8073     {
8074 	semsg(_("E741: Value is locked: %s"),
8075 				name == NULL ? (char_u *)_("Unknown")
8076 					     : use_gettext ? (char_u *)_(name)
8077 					     : name);
8078 	return TRUE;
8079     }
8080     if (lock & VAR_FIXED)
8081     {
8082 	semsg(_("E742: Cannot change value of %s"),
8083 				name == NULL ? (char_u *)_("Unknown")
8084 					     : use_gettext ? (char_u *)_(name)
8085 					     : name);
8086 	return TRUE;
8087     }
8088     return FALSE;
8089 }
8090 
8091 /*
8092  * Return TRUE if typeval "tv" and its value are set to be locked (immutable).
8093  * Also give an error message, using "name" or _("name") when use_gettext is
8094  * TRUE.
8095  */
8096     static int
8097 tv_check_lock(typval_T *tv, char_u *name, int use_gettext)
8098 {
8099     int	lock = 0;
8100 
8101     switch (tv->v_type)
8102     {
8103 	case VAR_BLOB:
8104 	    if (tv->vval.v_blob != NULL)
8105 		lock = tv->vval.v_blob->bv_lock;
8106 	    break;
8107 	case VAR_LIST:
8108 	    if (tv->vval.v_list != NULL)
8109 		lock = tv->vval.v_list->lv_lock;
8110 	    break;
8111 	case VAR_DICT:
8112 	    if (tv->vval.v_dict != NULL)
8113 		lock = tv->vval.v_dict->dv_lock;
8114 	    break;
8115 	default:
8116 	    break;
8117     }
8118     return var_check_lock(tv->v_lock, name, use_gettext)
8119 		    || (lock != 0 && var_check_lock(lock, name, use_gettext));
8120 }
8121 
8122 /*
8123  * Check if a variable name is valid.
8124  * Return FALSE and give an error if not.
8125  */
8126     int
8127 valid_varname(char_u *varname)
8128 {
8129     char_u *p;
8130 
8131     for (p = varname; *p != NUL; ++p)
8132 	if (!eval_isnamec1(*p) && (p == varname || !VIM_ISDIGIT(*p))
8133 						   && *p != AUTOLOAD_CHAR)
8134 	{
8135 	    semsg(_(e_illvar), varname);
8136 	    return FALSE;
8137 	}
8138     return TRUE;
8139 }
8140 
8141 /*
8142  * Copy the values from typval_T "from" to typval_T "to".
8143  * When needed allocates string or increases reference count.
8144  * Does not make a copy of a list, blob or dict but copies the reference!
8145  * It is OK for "from" and "to" to point to the same item.  This is used to
8146  * make a copy later.
8147  */
8148     void
8149 copy_tv(typval_T *from, typval_T *to)
8150 {
8151     to->v_type = from->v_type;
8152     to->v_lock = 0;
8153     switch (from->v_type)
8154     {
8155 	case VAR_NUMBER:
8156 	case VAR_SPECIAL:
8157 	    to->vval.v_number = from->vval.v_number;
8158 	    break;
8159 	case VAR_FLOAT:
8160 #ifdef FEAT_FLOAT
8161 	    to->vval.v_float = from->vval.v_float;
8162 	    break;
8163 #endif
8164 	case VAR_JOB:
8165 #ifdef FEAT_JOB_CHANNEL
8166 	    to->vval.v_job = from->vval.v_job;
8167 	    if (to->vval.v_job != NULL)
8168 		++to->vval.v_job->jv_refcount;
8169 	    break;
8170 #endif
8171 	case VAR_CHANNEL:
8172 #ifdef FEAT_JOB_CHANNEL
8173 	    to->vval.v_channel = from->vval.v_channel;
8174 	    if (to->vval.v_channel != NULL)
8175 		++to->vval.v_channel->ch_refcount;
8176 	    break;
8177 #endif
8178 	case VAR_STRING:
8179 	case VAR_FUNC:
8180 	    if (from->vval.v_string == NULL)
8181 		to->vval.v_string = NULL;
8182 	    else
8183 	    {
8184 		to->vval.v_string = vim_strsave(from->vval.v_string);
8185 		if (from->v_type == VAR_FUNC)
8186 		    func_ref(to->vval.v_string);
8187 	    }
8188 	    break;
8189 	case VAR_PARTIAL:
8190 	    if (from->vval.v_partial == NULL)
8191 		to->vval.v_partial = NULL;
8192 	    else
8193 	    {
8194 		to->vval.v_partial = from->vval.v_partial;
8195 		++to->vval.v_partial->pt_refcount;
8196 	    }
8197 	    break;
8198 	case VAR_BLOB:
8199 	    if (from->vval.v_blob == NULL)
8200 		to->vval.v_blob = NULL;
8201 	    else
8202 	    {
8203 		to->vval.v_blob = from->vval.v_blob;
8204 		++to->vval.v_blob->bv_refcount;
8205 	    }
8206 	    break;
8207 	case VAR_LIST:
8208 	    if (from->vval.v_list == NULL)
8209 		to->vval.v_list = NULL;
8210 	    else
8211 	    {
8212 		to->vval.v_list = from->vval.v_list;
8213 		++to->vval.v_list->lv_refcount;
8214 	    }
8215 	    break;
8216 	case VAR_DICT:
8217 	    if (from->vval.v_dict == NULL)
8218 		to->vval.v_dict = NULL;
8219 	    else
8220 	    {
8221 		to->vval.v_dict = from->vval.v_dict;
8222 		++to->vval.v_dict->dv_refcount;
8223 	    }
8224 	    break;
8225 	case VAR_UNKNOWN:
8226 	    internal_error("copy_tv(UNKNOWN)");
8227 	    break;
8228     }
8229 }
8230 
8231 /*
8232  * Make a copy of an item.
8233  * Lists and Dictionaries are also copied.  A deep copy if "deep" is set.
8234  * For deepcopy() "copyID" is zero for a full copy or the ID for when a
8235  * reference to an already copied list/dict can be used.
8236  * Returns FAIL or OK.
8237  */
8238     int
8239 item_copy(
8240     typval_T	*from,
8241     typval_T	*to,
8242     int		deep,
8243     int		copyID)
8244 {
8245     static int	recurse = 0;
8246     int		ret = OK;
8247 
8248     if (recurse >= DICT_MAXNEST)
8249     {
8250 	emsg(_("E698: variable nested too deep for making a copy"));
8251 	return FAIL;
8252     }
8253     ++recurse;
8254 
8255     switch (from->v_type)
8256     {
8257 	case VAR_NUMBER:
8258 	case VAR_FLOAT:
8259 	case VAR_STRING:
8260 	case VAR_FUNC:
8261 	case VAR_PARTIAL:
8262 	case VAR_SPECIAL:
8263 	case VAR_JOB:
8264 	case VAR_CHANNEL:
8265 	    copy_tv(from, to);
8266 	    break;
8267 	case VAR_LIST:
8268 	    to->v_type = VAR_LIST;
8269 	    to->v_lock = 0;
8270 	    if (from->vval.v_list == NULL)
8271 		to->vval.v_list = NULL;
8272 	    else if (copyID != 0 && from->vval.v_list->lv_copyID == copyID)
8273 	    {
8274 		/* use the copy made earlier */
8275 		to->vval.v_list = from->vval.v_list->lv_copylist;
8276 		++to->vval.v_list->lv_refcount;
8277 	    }
8278 	    else
8279 		to->vval.v_list = list_copy(from->vval.v_list, deep, copyID);
8280 	    if (to->vval.v_list == NULL)
8281 		ret = FAIL;
8282 	    break;
8283 	case VAR_BLOB:
8284 	    ret = blob_copy(from, to);
8285 	    break;
8286 	case VAR_DICT:
8287 	    to->v_type = VAR_DICT;
8288 	    to->v_lock = 0;
8289 	    if (from->vval.v_dict == NULL)
8290 		to->vval.v_dict = NULL;
8291 	    else if (copyID != 0 && from->vval.v_dict->dv_copyID == copyID)
8292 	    {
8293 		/* use the copy made earlier */
8294 		to->vval.v_dict = from->vval.v_dict->dv_copydict;
8295 		++to->vval.v_dict->dv_refcount;
8296 	    }
8297 	    else
8298 		to->vval.v_dict = dict_copy(from->vval.v_dict, deep, copyID);
8299 	    if (to->vval.v_dict == NULL)
8300 		ret = FAIL;
8301 	    break;
8302 	case VAR_UNKNOWN:
8303 	    internal_error("item_copy(UNKNOWN)");
8304 	    ret = FAIL;
8305     }
8306     --recurse;
8307     return ret;
8308 }
8309 
8310 /*
8311  * This function is used by f_input() and f_inputdialog() functions. The third
8312  * argument to f_input() specifies the type of completion to use at the
8313  * prompt. The third argument to f_inputdialog() specifies the value to return
8314  * when the user cancels the prompt.
8315  */
8316     void
8317 get_user_input(
8318     typval_T	*argvars,
8319     typval_T	*rettv,
8320     int		inputdialog,
8321     int		secret)
8322 {
8323     char_u	*prompt = tv_get_string_chk(&argvars[0]);
8324     char_u	*p = NULL;
8325     int		c;
8326     char_u	buf[NUMBUFLEN];
8327     int		cmd_silent_save = cmd_silent;
8328     char_u	*defstr = (char_u *)"";
8329     int		xp_type = EXPAND_NOTHING;
8330     char_u	*xp_arg = NULL;
8331 
8332     rettv->v_type = VAR_STRING;
8333     rettv->vval.v_string = NULL;
8334 
8335 #ifdef NO_CONSOLE_INPUT
8336     /* While starting up, there is no place to enter text. When running tests
8337      * with --not-a-term we assume feedkeys() will be used. */
8338     if (no_console_input() && !is_not_a_term())
8339 	return;
8340 #endif
8341 
8342     cmd_silent = FALSE;		/* Want to see the prompt. */
8343     if (prompt != NULL)
8344     {
8345 	/* Only the part of the message after the last NL is considered as
8346 	 * prompt for the command line */
8347 	p = vim_strrchr(prompt, '\n');
8348 	if (p == NULL)
8349 	    p = prompt;
8350 	else
8351 	{
8352 	    ++p;
8353 	    c = *p;
8354 	    *p = NUL;
8355 	    msg_start();
8356 	    msg_clr_eos();
8357 	    msg_puts_attr((char *)prompt, echo_attr);
8358 	    msg_didout = FALSE;
8359 	    msg_starthere();
8360 	    *p = c;
8361 	}
8362 	cmdline_row = msg_row;
8363 
8364 	if (argvars[1].v_type != VAR_UNKNOWN)
8365 	{
8366 	    defstr = tv_get_string_buf_chk(&argvars[1], buf);
8367 	    if (defstr != NULL)
8368 		stuffReadbuffSpec(defstr);
8369 
8370 	    if (!inputdialog && argvars[2].v_type != VAR_UNKNOWN)
8371 	    {
8372 		char_u	*xp_name;
8373 		int	xp_namelen;
8374 		long	argt;
8375 
8376 		/* input() with a third argument: completion */
8377 		rettv->vval.v_string = NULL;
8378 
8379 		xp_name = tv_get_string_buf_chk(&argvars[2], buf);
8380 		if (xp_name == NULL)
8381 		    return;
8382 
8383 		xp_namelen = (int)STRLEN(xp_name);
8384 
8385 		if (parse_compl_arg(xp_name, xp_namelen, &xp_type, &argt,
8386 							     &xp_arg) == FAIL)
8387 		    return;
8388 	    }
8389 	}
8390 
8391 	if (defstr != NULL)
8392 	{
8393 	    int save_ex_normal_busy = ex_normal_busy;
8394 
8395 	    ex_normal_busy = 0;
8396 	    rettv->vval.v_string =
8397 		getcmdline_prompt(secret ? NUL : '@', p, echo_attr,
8398 							      xp_type, xp_arg);
8399 	    ex_normal_busy = save_ex_normal_busy;
8400 	}
8401 	if (inputdialog && rettv->vval.v_string == NULL
8402 		&& argvars[1].v_type != VAR_UNKNOWN
8403 		&& argvars[2].v_type != VAR_UNKNOWN)
8404 	    rettv->vval.v_string = vim_strsave(tv_get_string_buf(
8405 							   &argvars[2], buf));
8406 
8407 	vim_free(xp_arg);
8408 
8409 	/* since the user typed this, no need to wait for return */
8410 	need_wait_return = FALSE;
8411 	msg_didout = FALSE;
8412     }
8413     cmd_silent = cmd_silent_save;
8414 }
8415 
8416 /*
8417  * ":echo expr1 ..."	print each argument separated with a space, add a
8418  *			newline at the end.
8419  * ":echon expr1 ..."	print each argument plain.
8420  */
8421     void
8422 ex_echo(exarg_T *eap)
8423 {
8424     char_u	*arg = eap->arg;
8425     typval_T	rettv;
8426     char_u	*tofree;
8427     char_u	*p;
8428     int		needclr = TRUE;
8429     int		atstart = TRUE;
8430     char_u	numbuf[NUMBUFLEN];
8431     int		did_emsg_before = did_emsg;
8432     int		called_emsg_before = called_emsg;
8433 
8434     if (eap->skip)
8435 	++emsg_skip;
8436     while (*arg != NUL && *arg != '|' && *arg != '\n' && !got_int)
8437     {
8438 	/* If eval1() causes an error message the text from the command may
8439 	 * still need to be cleared. E.g., "echo 22,44". */
8440 	need_clr_eos = needclr;
8441 
8442 	p = arg;
8443 	if (eval1(&arg, &rettv, !eap->skip) == FAIL)
8444 	{
8445 	    /*
8446 	     * Report the invalid expression unless the expression evaluation
8447 	     * has been cancelled due to an aborting error, an interrupt, or an
8448 	     * exception.
8449 	     */
8450 	    if (!aborting() && did_emsg == did_emsg_before
8451 					  && called_emsg == called_emsg_before)
8452 		semsg(_(e_invexpr2), p);
8453 	    need_clr_eos = FALSE;
8454 	    break;
8455 	}
8456 	need_clr_eos = FALSE;
8457 
8458 	if (!eap->skip)
8459 	{
8460 	    if (atstart)
8461 	    {
8462 		atstart = FALSE;
8463 		/* Call msg_start() after eval1(), evaluating the expression
8464 		 * may cause a message to appear. */
8465 		if (eap->cmdidx == CMD_echo)
8466 		{
8467 		    /* Mark the saved text as finishing the line, so that what
8468 		     * follows is displayed on a new line when scrolling back
8469 		     * at the more prompt. */
8470 		    msg_sb_eol();
8471 		    msg_start();
8472 		}
8473 	    }
8474 	    else if (eap->cmdidx == CMD_echo)
8475 		msg_puts_attr(" ", echo_attr);
8476 	    p = echo_string(&rettv, &tofree, numbuf, get_copyID());
8477 	    if (p != NULL)
8478 		for ( ; *p != NUL && !got_int; ++p)
8479 		{
8480 		    if (*p == '\n' || *p == '\r' || *p == TAB)
8481 		    {
8482 			if (*p != TAB && needclr)
8483 			{
8484 			    /* remove any text still there from the command */
8485 			    msg_clr_eos();
8486 			    needclr = FALSE;
8487 			}
8488 			msg_putchar_attr(*p, echo_attr);
8489 		    }
8490 		    else
8491 		    {
8492 			if (has_mbyte)
8493 			{
8494 			    int i = (*mb_ptr2len)(p);
8495 
8496 			    (void)msg_outtrans_len_attr(p, i, echo_attr);
8497 			    p += i - 1;
8498 			}
8499 			else
8500 			    (void)msg_outtrans_len_attr(p, 1, echo_attr);
8501 		    }
8502 		}
8503 	    vim_free(tofree);
8504 	}
8505 	clear_tv(&rettv);
8506 	arg = skipwhite(arg);
8507     }
8508     eap->nextcmd = check_nextcmd(arg);
8509 
8510     if (eap->skip)
8511 	--emsg_skip;
8512     else
8513     {
8514 	/* remove text that may still be there from the command */
8515 	if (needclr)
8516 	    msg_clr_eos();
8517 	if (eap->cmdidx == CMD_echo)
8518 	    msg_end();
8519     }
8520 }
8521 
8522 /*
8523  * ":echohl {name}".
8524  */
8525     void
8526 ex_echohl(exarg_T *eap)
8527 {
8528     echo_attr = syn_name2attr(eap->arg);
8529 }
8530 
8531 /*
8532  * ":execute expr1 ..."	execute the result of an expression.
8533  * ":echomsg expr1 ..."	Print a message
8534  * ":echoerr expr1 ..."	Print an error
8535  * Each gets spaces around each argument and a newline at the end for
8536  * echo commands
8537  */
8538     void
8539 ex_execute(exarg_T *eap)
8540 {
8541     char_u	*arg = eap->arg;
8542     typval_T	rettv;
8543     int		ret = OK;
8544     char_u	*p;
8545     garray_T	ga;
8546     int		len;
8547     int		save_did_emsg;
8548 
8549     ga_init2(&ga, 1, 80);
8550 
8551     if (eap->skip)
8552 	++emsg_skip;
8553     while (*arg != NUL && *arg != '|' && *arg != '\n')
8554     {
8555 	ret = eval1_emsg(&arg, &rettv, !eap->skip);
8556 	if (ret == FAIL)
8557 	    break;
8558 
8559 	if (!eap->skip)
8560 	{
8561 	    char_u   buf[NUMBUFLEN];
8562 
8563 	    if (eap->cmdidx == CMD_execute)
8564 		p = tv_get_string_buf(&rettv, buf);
8565 	    else
8566 		p = tv_stringify(&rettv, buf);
8567 	    len = (int)STRLEN(p);
8568 	    if (ga_grow(&ga, len + 2) == FAIL)
8569 	    {
8570 		clear_tv(&rettv);
8571 		ret = FAIL;
8572 		break;
8573 	    }
8574 	    if (ga.ga_len)
8575 		((char_u *)(ga.ga_data))[ga.ga_len++] = ' ';
8576 	    STRCPY((char_u *)(ga.ga_data) + ga.ga_len, p);
8577 	    ga.ga_len += len;
8578 	}
8579 
8580 	clear_tv(&rettv);
8581 	arg = skipwhite(arg);
8582     }
8583 
8584     if (ret != FAIL && ga.ga_data != NULL)
8585     {
8586 	if (eap->cmdidx == CMD_echomsg || eap->cmdidx == CMD_echoerr)
8587 	{
8588 	    /* Mark the already saved text as finishing the line, so that what
8589 	     * follows is displayed on a new line when scrolling back at the
8590 	     * more prompt. */
8591 	    msg_sb_eol();
8592 	}
8593 
8594 	if (eap->cmdidx == CMD_echomsg)
8595 	{
8596 	    msg_attr(ga.ga_data, echo_attr);
8597 	    out_flush();
8598 	}
8599 	else if (eap->cmdidx == CMD_echoerr)
8600 	{
8601 	    /* We don't want to abort following commands, restore did_emsg. */
8602 	    save_did_emsg = did_emsg;
8603 	    emsg(ga.ga_data);
8604 	    if (!force_abort)
8605 		did_emsg = save_did_emsg;
8606 	}
8607 	else if (eap->cmdidx == CMD_execute)
8608 	    do_cmdline((char_u *)ga.ga_data,
8609 		       eap->getline, eap->cookie, DOCMD_NOWAIT|DOCMD_VERBOSE);
8610     }
8611 
8612     ga_clear(&ga);
8613 
8614     if (eap->skip)
8615 	--emsg_skip;
8616 
8617     eap->nextcmd = check_nextcmd(arg);
8618 }
8619 
8620 /*
8621  * Find window specified by "vp" in tabpage "tp".
8622  */
8623     win_T *
8624 find_win_by_nr(
8625     typval_T	*vp,
8626     tabpage_T	*tp)	/* NULL for current tab page */
8627 {
8628     win_T	*wp;
8629     int		nr = (int)tv_get_number_chk(vp, NULL);
8630 
8631     if (nr < 0)
8632 	return NULL;
8633     if (nr == 0)
8634 	return curwin;
8635 
8636     FOR_ALL_WINDOWS_IN_TAB(tp, wp)
8637     {
8638 	if (nr >= LOWEST_WIN_ID)
8639 	{
8640 	    if (wp->w_id == nr)
8641 		return wp;
8642 	}
8643 	else if (--nr <= 0)
8644 	    break;
8645     }
8646     if (nr >= LOWEST_WIN_ID)
8647 	return NULL;
8648     return wp;
8649 }
8650 
8651 /*
8652  * Find a window: When using a Window ID in any tab page, when using a number
8653  * in the current tab page.
8654  */
8655     win_T *
8656 find_win_by_nr_or_id(typval_T *vp)
8657 {
8658     int	nr = (int)tv_get_number_chk(vp, NULL);
8659 
8660     if (nr >= LOWEST_WIN_ID)
8661 	return win_id2wp(tv_get_number(vp));
8662     return find_win_by_nr(vp, NULL);
8663 }
8664 
8665 /*
8666  * Find window specified by "wvp" in tabpage "tvp".
8667  */
8668     win_T *
8669 find_tabwin(
8670     typval_T	*wvp,	/* VAR_UNKNOWN for current window */
8671     typval_T	*tvp)	/* VAR_UNKNOWN for current tab page */
8672 {
8673     win_T	*wp = NULL;
8674     tabpage_T	*tp = NULL;
8675     long	n;
8676 
8677     if (wvp->v_type != VAR_UNKNOWN)
8678     {
8679 	if (tvp->v_type != VAR_UNKNOWN)
8680 	{
8681 	    n = (long)tv_get_number(tvp);
8682 	    if (n >= 0)
8683 		tp = find_tabpage(n);
8684 	}
8685 	else
8686 	    tp = curtab;
8687 
8688 	if (tp != NULL)
8689 	    wp = find_win_by_nr(wvp, tp);
8690     }
8691     else
8692 	wp = curwin;
8693 
8694     return wp;
8695 }
8696 
8697 /*
8698  * getwinvar() and gettabwinvar()
8699  */
8700     void
8701 getwinvar(
8702     typval_T	*argvars,
8703     typval_T	*rettv,
8704     int		off)	    /* 1 for gettabwinvar() */
8705 {
8706     win_T	*win;
8707     char_u	*varname;
8708     dictitem_T	*v;
8709     tabpage_T	*tp = NULL;
8710     int		done = FALSE;
8711     win_T	*oldcurwin;
8712     tabpage_T	*oldtabpage;
8713     int		need_switch_win;
8714 
8715     if (off == 1)
8716 	tp = find_tabpage((int)tv_get_number_chk(&argvars[0], NULL));
8717     else
8718 	tp = curtab;
8719     win = find_win_by_nr(&argvars[off], tp);
8720     varname = tv_get_string_chk(&argvars[off + 1]);
8721     ++emsg_off;
8722 
8723     rettv->v_type = VAR_STRING;
8724     rettv->vval.v_string = NULL;
8725 
8726     if (win != NULL && varname != NULL)
8727     {
8728 	/* Set curwin to be our win, temporarily.  Also set the tabpage,
8729 	 * otherwise the window is not valid. Only do this when needed,
8730 	 * autocommands get blocked. */
8731 	need_switch_win = !(tp == curtab && win == curwin);
8732 	if (!need_switch_win
8733 		  || switch_win(&oldcurwin, &oldtabpage, win, tp, TRUE) == OK)
8734 	{
8735 	    if (*varname == '&')
8736 	    {
8737 		if (varname[1] == NUL)
8738 		{
8739 		    /* get all window-local options in a dict */
8740 		    dict_T	*opts = get_winbuf_options(FALSE);
8741 
8742 		    if (opts != NULL)
8743 		    {
8744 			rettv_dict_set(rettv, opts);
8745 			done = TRUE;
8746 		    }
8747 		}
8748 		else if (get_option_tv(&varname, rettv, 1) == OK)
8749 		    /* window-local-option */
8750 		    done = TRUE;
8751 	    }
8752 	    else
8753 	    {
8754 		/* Look up the variable. */
8755 		/* Let getwinvar({nr}, "") return the "w:" dictionary. */
8756 		v = find_var_in_ht(&win->w_vars->dv_hashtab, 'w',
8757 							      varname, FALSE);
8758 		if (v != NULL)
8759 		{
8760 		    copy_tv(&v->di_tv, rettv);
8761 		    done = TRUE;
8762 		}
8763 	    }
8764 	}
8765 
8766 	if (need_switch_win)
8767 	    /* restore previous notion of curwin */
8768 	    restore_win(oldcurwin, oldtabpage, TRUE);
8769     }
8770 
8771     if (!done && argvars[off + 2].v_type != VAR_UNKNOWN)
8772 	/* use the default return value */
8773 	copy_tv(&argvars[off + 2], rettv);
8774 
8775     --emsg_off;
8776 }
8777 
8778 /*
8779  * "setwinvar()" and "settabwinvar()" functions
8780  */
8781     void
8782 setwinvar(typval_T *argvars, typval_T *rettv UNUSED, int off)
8783 {
8784     win_T	*win;
8785     win_T	*save_curwin;
8786     tabpage_T	*save_curtab;
8787     int		need_switch_win;
8788     char_u	*varname, *winvarname;
8789     typval_T	*varp;
8790     char_u	nbuf[NUMBUFLEN];
8791     tabpage_T	*tp = NULL;
8792 
8793     if (check_secure())
8794 	return;
8795 
8796     if (off == 1)
8797 	tp = find_tabpage((int)tv_get_number_chk(&argvars[0], NULL));
8798     else
8799 	tp = curtab;
8800     win = find_win_by_nr(&argvars[off], tp);
8801     varname = tv_get_string_chk(&argvars[off + 1]);
8802     varp = &argvars[off + 2];
8803 
8804     if (win != NULL && varname != NULL && varp != NULL)
8805     {
8806 	need_switch_win = !(tp == curtab && win == curwin);
8807 	if (!need_switch_win
8808 	       || switch_win(&save_curwin, &save_curtab, win, tp, TRUE) == OK)
8809 	{
8810 	    if (*varname == '&')
8811 	    {
8812 		long	numval;
8813 		char_u	*strval;
8814 		int		error = FALSE;
8815 
8816 		++varname;
8817 		numval = (long)tv_get_number_chk(varp, &error);
8818 		strval = tv_get_string_buf_chk(varp, nbuf);
8819 		if (!error && strval != NULL)
8820 		    set_option_value(varname, numval, strval, OPT_LOCAL);
8821 	    }
8822 	    else
8823 	    {
8824 		winvarname = alloc((unsigned)STRLEN(varname) + 3);
8825 		if (winvarname != NULL)
8826 		{
8827 		    STRCPY(winvarname, "w:");
8828 		    STRCPY(winvarname + 2, varname);
8829 		    set_var(winvarname, varp, TRUE);
8830 		    vim_free(winvarname);
8831 		}
8832 	    }
8833 	}
8834 	if (need_switch_win)
8835 	    restore_win(save_curwin, save_curtab, TRUE);
8836     }
8837 }
8838 
8839 /*
8840  * Skip over the name of an option: "&option", "&g:option" or "&l:option".
8841  * "arg" points to the "&" or '+' when called, to "option" when returning.
8842  * Returns NULL when no option name found.  Otherwise pointer to the char
8843  * after the option name.
8844  */
8845     static char_u *
8846 find_option_end(char_u **arg, int *opt_flags)
8847 {
8848     char_u	*p = *arg;
8849 
8850     ++p;
8851     if (*p == 'g' && p[1] == ':')
8852     {
8853 	*opt_flags = OPT_GLOBAL;
8854 	p += 2;
8855     }
8856     else if (*p == 'l' && p[1] == ':')
8857     {
8858 	*opt_flags = OPT_LOCAL;
8859 	p += 2;
8860     }
8861     else
8862 	*opt_flags = 0;
8863 
8864     if (!ASCII_ISALPHA(*p))
8865 	return NULL;
8866     *arg = p;
8867 
8868     if (p[0] == 't' && p[1] == '_' && p[2] != NUL && p[3] != NUL)
8869 	p += 4;	    /* termcap option */
8870     else
8871 	while (ASCII_ISALPHA(*p))
8872 	    ++p;
8873     return p;
8874 }
8875 
8876 /*
8877  * Return the autoload script name for a function or variable name.
8878  * Returns NULL when out of memory.
8879  */
8880     char_u *
8881 autoload_name(char_u *name)
8882 {
8883     char_u	*p;
8884     char_u	*scriptname;
8885 
8886     /* Get the script file name: replace '#' with '/', append ".vim". */
8887     scriptname = alloc((unsigned)(STRLEN(name) + 14));
8888     if (scriptname == NULL)
8889 	return FALSE;
8890     STRCPY(scriptname, "autoload/");
8891     STRCAT(scriptname, name);
8892     *vim_strrchr(scriptname, AUTOLOAD_CHAR) = NUL;
8893     STRCAT(scriptname, ".vim");
8894     while ((p = vim_strchr(scriptname, AUTOLOAD_CHAR)) != NULL)
8895 	*p = '/';
8896     return scriptname;
8897 }
8898 
8899 /*
8900  * If "name" has a package name try autoloading the script for it.
8901  * Return TRUE if a package was loaded.
8902  */
8903     int
8904 script_autoload(
8905     char_u	*name,
8906     int		reload)	    /* load script again when already loaded */
8907 {
8908     char_u	*p;
8909     char_u	*scriptname, *tofree;
8910     int		ret = FALSE;
8911     int		i;
8912 
8913     /* If there is no '#' after name[0] there is no package name. */
8914     p = vim_strchr(name, AUTOLOAD_CHAR);
8915     if (p == NULL || p == name)
8916 	return FALSE;
8917 
8918     tofree = scriptname = autoload_name(name);
8919 
8920     /* Find the name in the list of previously loaded package names.  Skip
8921      * "autoload/", it's always the same. */
8922     for (i = 0; i < ga_loaded.ga_len; ++i)
8923 	if (STRCMP(((char_u **)ga_loaded.ga_data)[i] + 9, scriptname + 9) == 0)
8924 	    break;
8925     if (!reload && i < ga_loaded.ga_len)
8926 	ret = FALSE;	    /* was loaded already */
8927     else
8928     {
8929 	/* Remember the name if it wasn't loaded already. */
8930 	if (i == ga_loaded.ga_len && ga_grow(&ga_loaded, 1) == OK)
8931 	{
8932 	    ((char_u **)ga_loaded.ga_data)[ga_loaded.ga_len++] = scriptname;
8933 	    tofree = NULL;
8934 	}
8935 
8936 	/* Try loading the package from $VIMRUNTIME/autoload/<name>.vim */
8937 	if (source_runtime(scriptname, 0) == OK)
8938 	    ret = TRUE;
8939     }
8940 
8941     vim_free(tofree);
8942     return ret;
8943 }
8944 
8945 #if defined(FEAT_VIMINFO) || defined(FEAT_SESSION)
8946 typedef enum
8947 {
8948     VAR_FLAVOUR_DEFAULT,	/* doesn't start with uppercase */
8949     VAR_FLAVOUR_SESSION,	/* starts with uppercase, some lower */
8950     VAR_FLAVOUR_VIMINFO		/* all uppercase */
8951 } var_flavour_T;
8952 
8953     static var_flavour_T
8954 var_flavour(char_u *varname)
8955 {
8956     char_u *p = varname;
8957 
8958     if (ASCII_ISUPPER(*p))
8959     {
8960 	while (*(++p))
8961 	    if (ASCII_ISLOWER(*p))
8962 		return VAR_FLAVOUR_SESSION;
8963 	return VAR_FLAVOUR_VIMINFO;
8964     }
8965     else
8966 	return VAR_FLAVOUR_DEFAULT;
8967 }
8968 #endif
8969 
8970 #if defined(FEAT_VIMINFO) || defined(PROTO)
8971 /*
8972  * Restore global vars that start with a capital from the viminfo file
8973  */
8974     int
8975 read_viminfo_varlist(vir_T *virp, int writing)
8976 {
8977     char_u	*tab;
8978     int		type = VAR_NUMBER;
8979     typval_T	tv;
8980     funccal_entry_T funccal_entry;
8981 
8982     if (!writing && (find_viminfo_parameter('!') != NULL))
8983     {
8984 	tab = vim_strchr(virp->vir_line + 1, '\t');
8985 	if (tab != NULL)
8986 	{
8987 	    *tab++ = '\0';	/* isolate the variable name */
8988 	    switch (*tab)
8989 	    {
8990 		case 'S': type = VAR_STRING; break;
8991 #ifdef FEAT_FLOAT
8992 		case 'F': type = VAR_FLOAT; break;
8993 #endif
8994 		case 'D': type = VAR_DICT; break;
8995 		case 'L': type = VAR_LIST; break;
8996 		case 'B': type = VAR_BLOB; break;
8997 		case 'X': type = VAR_SPECIAL; break;
8998 	    }
8999 
9000 	    tab = vim_strchr(tab, '\t');
9001 	    if (tab != NULL)
9002 	    {
9003 		tv.v_type = type;
9004 		if (type == VAR_STRING || type == VAR_DICT
9005 			|| type == VAR_LIST || type == VAR_BLOB)
9006 		    tv.vval.v_string = viminfo_readstring(virp,
9007 				       (int)(tab - virp->vir_line + 1), TRUE);
9008 #ifdef FEAT_FLOAT
9009 		else if (type == VAR_FLOAT)
9010 		    (void)string2float(tab + 1, &tv.vval.v_float);
9011 #endif
9012 		else
9013 		    tv.vval.v_number = atol((char *)tab + 1);
9014 		if (type == VAR_DICT || type == VAR_LIST)
9015 		{
9016 		    typval_T *etv = eval_expr(tv.vval.v_string, NULL);
9017 
9018 		    if (etv == NULL)
9019 			/* Failed to parse back the dict or list, use it as a
9020 			 * string. */
9021 			tv.v_type = VAR_STRING;
9022 		    else
9023 		    {
9024 			vim_free(tv.vval.v_string);
9025 			tv = *etv;
9026 			vim_free(etv);
9027 		    }
9028 		}
9029 		else if (type == VAR_BLOB)
9030 		{
9031 		    blob_T *blob = string2blob(tv.vval.v_string);
9032 
9033 		    if (blob == NULL)
9034 			// Failed to parse back the blob, use it as a string.
9035 			tv.v_type = VAR_STRING;
9036 		    else
9037 		    {
9038 			vim_free(tv.vval.v_string);
9039 			tv.v_type = VAR_BLOB;
9040 			tv.vval.v_blob = blob;
9041 		    }
9042 		}
9043 
9044 		/* when in a function use global variables */
9045 		save_funccal(&funccal_entry);
9046 		set_var(virp->vir_line + 1, &tv, FALSE);
9047 		restore_funccal();
9048 
9049 		if (tv.v_type == VAR_STRING)
9050 		    vim_free(tv.vval.v_string);
9051 		else if (tv.v_type == VAR_DICT || tv.v_type == VAR_LIST ||
9052 			tv.v_type == VAR_BLOB)
9053 		    clear_tv(&tv);
9054 	    }
9055 	}
9056     }
9057 
9058     return viminfo_readline(virp);
9059 }
9060 
9061 /*
9062  * Write global vars that start with a capital to the viminfo file
9063  */
9064     void
9065 write_viminfo_varlist(FILE *fp)
9066 {
9067     hashitem_T	*hi;
9068     dictitem_T	*this_var;
9069     int		todo;
9070     char	*s = "";
9071     char_u	*p;
9072     char_u	*tofree;
9073     char_u	numbuf[NUMBUFLEN];
9074 
9075     if (find_viminfo_parameter('!') == NULL)
9076 	return;
9077 
9078     fputs(_("\n# global variables:\n"), fp);
9079 
9080     todo = (int)globvarht.ht_used;
9081     for (hi = globvarht.ht_array; todo > 0; ++hi)
9082     {
9083 	if (!HASHITEM_EMPTY(hi))
9084 	{
9085 	    --todo;
9086 	    this_var = HI2DI(hi);
9087 	    if (var_flavour(this_var->di_key) == VAR_FLAVOUR_VIMINFO)
9088 	    {
9089 		switch (this_var->di_tv.v_type)
9090 		{
9091 		    case VAR_STRING: s = "STR"; break;
9092 		    case VAR_NUMBER: s = "NUM"; break;
9093 		    case VAR_FLOAT:  s = "FLO"; break;
9094 		    case VAR_DICT:   s = "DIC"; break;
9095 		    case VAR_LIST:   s = "LIS"; break;
9096 		    case VAR_BLOB:   s = "BLO"; break;
9097 		    case VAR_SPECIAL: s = "XPL"; break;
9098 
9099 		    case VAR_UNKNOWN:
9100 		    case VAR_FUNC:
9101 		    case VAR_PARTIAL:
9102 		    case VAR_JOB:
9103 		    case VAR_CHANNEL:
9104 				     continue;
9105 		}
9106 		fprintf(fp, "!%s\t%s\t", this_var->di_key, s);
9107 		if (this_var->di_tv.v_type == VAR_SPECIAL)
9108 		{
9109 		    sprintf((char *)numbuf, "%ld",
9110 					  (long)this_var->di_tv.vval.v_number);
9111 		    p = numbuf;
9112 		    tofree = NULL;
9113 		}
9114 		else
9115 		    p = echo_string(&this_var->di_tv, &tofree, numbuf, 0);
9116 		if (p != NULL)
9117 		    viminfo_writestring(fp, p);
9118 		vim_free(tofree);
9119 	    }
9120 	}
9121     }
9122 }
9123 #endif
9124 
9125 #if defined(FEAT_SESSION) || defined(PROTO)
9126     int
9127 store_session_globals(FILE *fd)
9128 {
9129     hashitem_T	*hi;
9130     dictitem_T	*this_var;
9131     int		todo;
9132     char_u	*p, *t;
9133 
9134     todo = (int)globvarht.ht_used;
9135     for (hi = globvarht.ht_array; todo > 0; ++hi)
9136     {
9137 	if (!HASHITEM_EMPTY(hi))
9138 	{
9139 	    --todo;
9140 	    this_var = HI2DI(hi);
9141 	    if ((this_var->di_tv.v_type == VAR_NUMBER
9142 			|| this_var->di_tv.v_type == VAR_STRING)
9143 		    && var_flavour(this_var->di_key) == VAR_FLAVOUR_SESSION)
9144 	    {
9145 		/* Escape special characters with a backslash.  Turn a LF and
9146 		 * CR into \n and \r. */
9147 		p = vim_strsave_escaped(tv_get_string(&this_var->di_tv),
9148 							(char_u *)"\\\"\n\r");
9149 		if (p == NULL)	    /* out of memory */
9150 		    break;
9151 		for (t = p; *t != NUL; ++t)
9152 		    if (*t == '\n')
9153 			*t = 'n';
9154 		    else if (*t == '\r')
9155 			*t = 'r';
9156 		if ((fprintf(fd, "let %s = %c%s%c",
9157 				this_var->di_key,
9158 				(this_var->di_tv.v_type == VAR_STRING) ? '"'
9159 									: ' ',
9160 				p,
9161 				(this_var->di_tv.v_type == VAR_STRING) ? '"'
9162 								   : ' ') < 0)
9163 			|| put_eol(fd) == FAIL)
9164 		{
9165 		    vim_free(p);
9166 		    return FAIL;
9167 		}
9168 		vim_free(p);
9169 	    }
9170 #ifdef FEAT_FLOAT
9171 	    else if (this_var->di_tv.v_type == VAR_FLOAT
9172 		    && var_flavour(this_var->di_key) == VAR_FLAVOUR_SESSION)
9173 	    {
9174 		float_T f = this_var->di_tv.vval.v_float;
9175 		int sign = ' ';
9176 
9177 		if (f < 0)
9178 		{
9179 		    f = -f;
9180 		    sign = '-';
9181 		}
9182 		if ((fprintf(fd, "let %s = %c%f",
9183 					       this_var->di_key, sign, f) < 0)
9184 			|| put_eol(fd) == FAIL)
9185 		    return FAIL;
9186 	    }
9187 #endif
9188 	}
9189     }
9190     return OK;
9191 }
9192 #endif
9193 
9194 /*
9195  * Display script name where an item was last set.
9196  * Should only be invoked when 'verbose' is non-zero.
9197  */
9198     void
9199 last_set_msg(sctx_T script_ctx)
9200 {
9201     char_u *p;
9202 
9203     if (script_ctx.sc_sid != 0)
9204     {
9205 	p = home_replace_save(NULL, get_scriptname(script_ctx.sc_sid));
9206 	if (p != NULL)
9207 	{
9208 	    verbose_enter();
9209 	    msg_puts(_("\n\tLast set from "));
9210 	    msg_puts((char *)p);
9211 	    if (script_ctx.sc_lnum > 0)
9212 	    {
9213 		msg_puts(_(" line "));
9214 		msg_outnum((long)script_ctx.sc_lnum);
9215 	    }
9216 	    verbose_leave();
9217 	    vim_free(p);
9218 	}
9219     }
9220 }
9221 
9222 /*
9223  * Reset v:option_new, v:option_old and v:option_type.
9224  */
9225     void
9226 reset_v_option_vars(void)
9227 {
9228     set_vim_var_string(VV_OPTION_NEW,  NULL, -1);
9229     set_vim_var_string(VV_OPTION_OLD,  NULL, -1);
9230     set_vim_var_string(VV_OPTION_TYPE, NULL, -1);
9231 }
9232 
9233 /*
9234  * Prepare "gap" for an assert error and add the sourcing position.
9235  */
9236     void
9237 prepare_assert_error(garray_T *gap)
9238 {
9239     char buf[NUMBUFLEN];
9240 
9241     ga_init2(gap, 1, 100);
9242     if (sourcing_name != NULL)
9243     {
9244 	ga_concat(gap, sourcing_name);
9245 	if (sourcing_lnum > 0)
9246 	    ga_concat(gap, (char_u *)" ");
9247     }
9248     if (sourcing_lnum > 0)
9249     {
9250 	sprintf(buf, "line %ld", (long)sourcing_lnum);
9251 	ga_concat(gap, (char_u *)buf);
9252     }
9253     if (sourcing_name != NULL || sourcing_lnum > 0)
9254 	ga_concat(gap, (char_u *)": ");
9255 }
9256 
9257 /*
9258  * Add an assert error to v:errors.
9259  */
9260     void
9261 assert_error(garray_T *gap)
9262 {
9263     struct vimvar   *vp = &vimvars[VV_ERRORS];
9264 
9265     if (vp->vv_type != VAR_LIST || vimvars[VV_ERRORS].vv_list == NULL)
9266 	/* Make sure v:errors is a list. */
9267 	set_vim_var_list(VV_ERRORS, list_alloc());
9268     list_append_string(vimvars[VV_ERRORS].vv_list, gap->ga_data, gap->ga_len);
9269 }
9270 
9271     int
9272 assert_equal_common(typval_T *argvars, assert_type_T atype)
9273 {
9274     garray_T	ga;
9275 
9276     if (tv_equal(&argvars[0], &argvars[1], FALSE, FALSE)
9277 						   != (atype == ASSERT_EQUAL))
9278     {
9279 	prepare_assert_error(&ga);
9280 	fill_assert_error(&ga, &argvars[2], NULL, &argvars[0], &argvars[1],
9281 								       atype);
9282 	assert_error(&ga);
9283 	ga_clear(&ga);
9284 	return 1;
9285     }
9286     return 0;
9287 }
9288 
9289     int
9290 assert_equalfile(typval_T *argvars)
9291 {
9292     char_u	buf1[NUMBUFLEN];
9293     char_u	buf2[NUMBUFLEN];
9294     char_u	*fname1 = tv_get_string_buf_chk(&argvars[0], buf1);
9295     char_u	*fname2 = tv_get_string_buf_chk(&argvars[1], buf2);
9296     garray_T	ga;
9297     FILE	*fd1;
9298     FILE	*fd2;
9299 
9300     if (fname1 == NULL || fname2 == NULL)
9301 	return 0;
9302 
9303     IObuff[0] = NUL;
9304     fd1 = mch_fopen((char *)fname1, READBIN);
9305     if (fd1 == NULL)
9306     {
9307 	vim_snprintf((char *)IObuff, IOSIZE, (char *)e_notread, fname1);
9308     }
9309     else
9310     {
9311 	fd2 = mch_fopen((char *)fname2, READBIN);
9312 	if (fd2 == NULL)
9313 	{
9314 	    fclose(fd1);
9315 	    vim_snprintf((char *)IObuff, IOSIZE, (char *)e_notread, fname2);
9316 	}
9317 	else
9318 	{
9319 	    int c1, c2;
9320 	    long count = 0;
9321 
9322 	    for (;;)
9323 	    {
9324 		c1 = fgetc(fd1);
9325 		c2 = fgetc(fd2);
9326 		if (c1 == EOF)
9327 		{
9328 		    if (c2 != EOF)
9329 			STRCPY(IObuff, "first file is shorter");
9330 		    break;
9331 		}
9332 		else if (c2 == EOF)
9333 		{
9334 		    STRCPY(IObuff, "second file is shorter");
9335 		    break;
9336 		}
9337 		else if (c1 != c2)
9338 		{
9339 		    vim_snprintf((char *)IObuff, IOSIZE,
9340 					      "difference at byte %ld", count);
9341 		    break;
9342 		}
9343 		++count;
9344 	    }
9345 	    fclose(fd1);
9346 	    fclose(fd2);
9347 	}
9348     }
9349     if (IObuff[0] != NUL)
9350     {
9351 	prepare_assert_error(&ga);
9352 	ga_concat(&ga, IObuff);
9353 	assert_error(&ga);
9354 	ga_clear(&ga);
9355 	return 1;
9356     }
9357     return 0;
9358 }
9359 
9360     int
9361 assert_match_common(typval_T *argvars, assert_type_T atype)
9362 {
9363     garray_T	ga;
9364     char_u	buf1[NUMBUFLEN];
9365     char_u	buf2[NUMBUFLEN];
9366     char_u	*pat = tv_get_string_buf_chk(&argvars[0], buf1);
9367     char_u	*text = tv_get_string_buf_chk(&argvars[1], buf2);
9368 
9369     if (pat == NULL || text == NULL)
9370 	emsg(_(e_invarg));
9371     else if (pattern_match(pat, text, FALSE) != (atype == ASSERT_MATCH))
9372     {
9373 	prepare_assert_error(&ga);
9374 	fill_assert_error(&ga, &argvars[2], NULL, &argvars[0], &argvars[1],
9375 									atype);
9376 	assert_error(&ga);
9377 	ga_clear(&ga);
9378 	return 1;
9379     }
9380     return 0;
9381 }
9382 
9383     int
9384 assert_inrange(typval_T *argvars)
9385 {
9386     garray_T	ga;
9387     int		error = FALSE;
9388     char_u	*tofree;
9389     char	msg[200];
9390     char_u	numbuf[NUMBUFLEN];
9391 
9392 #ifdef FEAT_FLOAT
9393     if (argvars[0].v_type == VAR_FLOAT
9394 	    || argvars[1].v_type == VAR_FLOAT
9395 	    || argvars[2].v_type == VAR_FLOAT)
9396     {
9397 	float_T flower = tv_get_float(&argvars[0]);
9398 	float_T fupper = tv_get_float(&argvars[1]);
9399 	float_T factual = tv_get_float(&argvars[2]);
9400 
9401 	if (factual < flower || factual > fupper)
9402 	{
9403 	    prepare_assert_error(&ga);
9404 	    if (argvars[3].v_type != VAR_UNKNOWN)
9405 	    {
9406 		ga_concat(&ga, tv2string(&argvars[3], &tofree, numbuf, 0));
9407 		vim_free(tofree);
9408 	    }
9409 	    else
9410 	    {
9411 		vim_snprintf(msg, 200, "Expected range %g - %g, but got %g",
9412 						      flower, fupper, factual);
9413 		ga_concat(&ga, (char_u *)msg);
9414 	    }
9415 	    assert_error(&ga);
9416 	    ga_clear(&ga);
9417 	    return 1;
9418 	}
9419     }
9420     else
9421 #endif
9422     {
9423 	varnumber_T	lower = tv_get_number_chk(&argvars[0], &error);
9424 	varnumber_T	upper = tv_get_number_chk(&argvars[1], &error);
9425 	varnumber_T	actual = tv_get_number_chk(&argvars[2], &error);
9426 
9427 	if (error)
9428 	    return 0;
9429 	if (actual < lower || actual > upper)
9430 	{
9431 	    prepare_assert_error(&ga);
9432 	    if (argvars[3].v_type != VAR_UNKNOWN)
9433 	    {
9434 		ga_concat(&ga, tv2string(&argvars[3], &tofree, numbuf, 0));
9435 		vim_free(tofree);
9436 	    }
9437 	    else
9438 	    {
9439 		vim_snprintf(msg, 200, "Expected range %ld - %ld, but got %ld",
9440 				       (long)lower, (long)upper, (long)actual);
9441 		ga_concat(&ga, (char_u *)msg);
9442 	    }
9443 	    assert_error(&ga);
9444 	    ga_clear(&ga);
9445 	    return 1;
9446 	}
9447     }
9448     return 0;
9449 }
9450 
9451 /*
9452  * Common for assert_true() and assert_false().
9453  * Return non-zero for failure.
9454  */
9455     int
9456 assert_bool(typval_T *argvars, int isTrue)
9457 {
9458     int		error = FALSE;
9459     garray_T	ga;
9460 
9461     if (argvars[0].v_type == VAR_SPECIAL
9462 	    && argvars[0].vval.v_number == (isTrue ? VVAL_TRUE : VVAL_FALSE))
9463 	return 0;
9464     if (argvars[0].v_type != VAR_NUMBER
9465 	    || (tv_get_number_chk(&argvars[0], &error) == 0) == isTrue
9466 	    || error)
9467     {
9468 	prepare_assert_error(&ga);
9469 	fill_assert_error(&ga, &argvars[1],
9470 		(char_u *)(isTrue ? "True" : "False"),
9471 		NULL, &argvars[0], ASSERT_OTHER);
9472 	assert_error(&ga);
9473 	ga_clear(&ga);
9474 	return 1;
9475     }
9476     return 0;
9477 }
9478 
9479     int
9480 assert_report(typval_T *argvars)
9481 {
9482     garray_T	ga;
9483 
9484     prepare_assert_error(&ga);
9485     ga_concat(&ga, tv_get_string(&argvars[0]));
9486     assert_error(&ga);
9487     ga_clear(&ga);
9488     return 1;
9489 }
9490 
9491     int
9492 assert_exception(typval_T *argvars)
9493 {
9494     garray_T	ga;
9495     char_u	*error = tv_get_string_chk(&argvars[0]);
9496 
9497     if (vimvars[VV_EXCEPTION].vv_str == NULL)
9498     {
9499 	prepare_assert_error(&ga);
9500 	ga_concat(&ga, (char_u *)"v:exception is not set");
9501 	assert_error(&ga);
9502 	ga_clear(&ga);
9503 	return 1;
9504     }
9505     else if (error != NULL
9506 	&& strstr((char *)vimvars[VV_EXCEPTION].vv_str, (char *)error) == NULL)
9507     {
9508 	prepare_assert_error(&ga);
9509 	fill_assert_error(&ga, &argvars[1], NULL, &argvars[0],
9510 				  &vimvars[VV_EXCEPTION].vv_tv, ASSERT_OTHER);
9511 	assert_error(&ga);
9512 	ga_clear(&ga);
9513 	return 1;
9514     }
9515     return 0;
9516 }
9517 
9518     int
9519 assert_beeps(typval_T *argvars)
9520 {
9521     char_u	*cmd = tv_get_string_chk(&argvars[0]);
9522     garray_T	ga;
9523     int		ret = 0;
9524 
9525     called_vim_beep = FALSE;
9526     suppress_errthrow = TRUE;
9527     emsg_silent = FALSE;
9528     do_cmdline_cmd(cmd);
9529     if (!called_vim_beep)
9530     {
9531 	prepare_assert_error(&ga);
9532 	ga_concat(&ga, (char_u *)"command did not beep: ");
9533 	ga_concat(&ga, cmd);
9534 	assert_error(&ga);
9535 	ga_clear(&ga);
9536 	ret = 1;
9537     }
9538 
9539     suppress_errthrow = FALSE;
9540     emsg_on_display = FALSE;
9541     return ret;
9542 }
9543 
9544     int
9545 assert_fails(typval_T *argvars)
9546 {
9547     char_u	*cmd = tv_get_string_chk(&argvars[0]);
9548     garray_T	ga;
9549     int		ret = 0;
9550     char_u	numbuf[NUMBUFLEN];
9551     char_u	*tofree;
9552 
9553     called_emsg = FALSE;
9554     suppress_errthrow = TRUE;
9555     emsg_silent = TRUE;
9556     do_cmdline_cmd(cmd);
9557     if (!called_emsg)
9558     {
9559 	prepare_assert_error(&ga);
9560 	ga_concat(&ga, (char_u *)"command did not fail: ");
9561 	if (argvars[1].v_type != VAR_UNKNOWN
9562 					   && argvars[2].v_type != VAR_UNKNOWN)
9563 	{
9564 	    ga_concat(&ga, echo_string(&argvars[2], &tofree, numbuf, 0));
9565 	    vim_free(tofree);
9566 	}
9567 	else
9568 	    ga_concat(&ga, cmd);
9569 	assert_error(&ga);
9570 	ga_clear(&ga);
9571 	ret = 1;
9572     }
9573     else if (argvars[1].v_type != VAR_UNKNOWN)
9574     {
9575 	char_u	buf[NUMBUFLEN];
9576 	char	*error = (char *)tv_get_string_buf_chk(&argvars[1], buf);
9577 
9578 	if (error == NULL
9579 		  || strstr((char *)vimvars[VV_ERRMSG].vv_str, error) == NULL)
9580 	{
9581 	    prepare_assert_error(&ga);
9582 	    fill_assert_error(&ga, &argvars[2], NULL, &argvars[1],
9583 				     &vimvars[VV_ERRMSG].vv_tv, ASSERT_OTHER);
9584 	    assert_error(&ga);
9585 	    ga_clear(&ga);
9586 	ret = 1;
9587 	}
9588     }
9589 
9590     called_emsg = FALSE;
9591     suppress_errthrow = FALSE;
9592     emsg_silent = FALSE;
9593     emsg_on_display = FALSE;
9594     set_vim_var_string(VV_ERRMSG, NULL, 0);
9595     return ret;
9596 }
9597 
9598 /*
9599  * Append "p[clen]" to "gap", escaping unprintable characters.
9600  * Changes NL to \n, CR to \r, etc.
9601  */
9602     static void
9603 ga_concat_esc(garray_T *gap, char_u *p, int clen)
9604 {
9605     char_u  buf[NUMBUFLEN];
9606 
9607     if (clen > 1)
9608     {
9609 	mch_memmove(buf, p, clen);
9610 	buf[clen] = NUL;
9611 	ga_concat(gap, buf);
9612     }
9613     else switch (*p)
9614     {
9615 	case BS: ga_concat(gap, (char_u *)"\\b"); break;
9616 	case ESC: ga_concat(gap, (char_u *)"\\e"); break;
9617 	case FF: ga_concat(gap, (char_u *)"\\f"); break;
9618 	case NL: ga_concat(gap, (char_u *)"\\n"); break;
9619 	case TAB: ga_concat(gap, (char_u *)"\\t"); break;
9620 	case CAR: ga_concat(gap, (char_u *)"\\r"); break;
9621 	case '\\': ga_concat(gap, (char_u *)"\\\\"); break;
9622 	default:
9623 		   if (*p < ' ')
9624 		   {
9625 		       vim_snprintf((char *)buf, NUMBUFLEN, "\\x%02x", *p);
9626 		       ga_concat(gap, buf);
9627 		   }
9628 		   else
9629 		       ga_append(gap, *p);
9630 		   break;
9631     }
9632 }
9633 
9634 /*
9635  * Append "str" to "gap", escaping unprintable characters.
9636  * Changes NL to \n, CR to \r, etc.
9637  */
9638     static void
9639 ga_concat_shorten_esc(garray_T *gap, char_u *str)
9640 {
9641     char_u  *p;
9642     char_u  *s;
9643     int	    c;
9644     int	    clen;
9645     char_u  buf[NUMBUFLEN];
9646     int	    same_len;
9647 
9648     if (str == NULL)
9649     {
9650 	ga_concat(gap, (char_u *)"NULL");
9651 	return;
9652     }
9653 
9654     for (p = str; *p != NUL; ++p)
9655     {
9656 	same_len = 1;
9657 	s = p;
9658 	c = mb_ptr2char_adv(&s);
9659 	clen = s - p;
9660 	while (*s != NUL && c == mb_ptr2char(s))
9661 	{
9662 	    ++same_len;
9663 	    s += clen;
9664 	}
9665 	if (same_len > 20)
9666 	{
9667 	    ga_concat(gap, (char_u *)"\\[");
9668 	    ga_concat_esc(gap, p, clen);
9669 	    ga_concat(gap, (char_u *)" occurs ");
9670 	    vim_snprintf((char *)buf, NUMBUFLEN, "%d", same_len);
9671 	    ga_concat(gap, buf);
9672 	    ga_concat(gap, (char_u *)" times]");
9673 	    p = s - 1;
9674 	}
9675 	else
9676 	    ga_concat_esc(gap, p, clen);
9677     }
9678 }
9679 
9680 /*
9681  * Fill "gap" with information about an assert error.
9682  */
9683     void
9684 fill_assert_error(
9685     garray_T	*gap,
9686     typval_T	*opt_msg_tv,
9687     char_u      *exp_str,
9688     typval_T	*exp_tv,
9689     typval_T	*got_tv,
9690     assert_type_T atype)
9691 {
9692     char_u	numbuf[NUMBUFLEN];
9693     char_u	*tofree;
9694 
9695     if (opt_msg_tv->v_type != VAR_UNKNOWN)
9696     {
9697 	ga_concat(gap, echo_string(opt_msg_tv, &tofree, numbuf, 0));
9698 	vim_free(tofree);
9699 	ga_concat(gap, (char_u *)": ");
9700     }
9701 
9702     if (atype == ASSERT_MATCH || atype == ASSERT_NOTMATCH)
9703 	ga_concat(gap, (char_u *)"Pattern ");
9704     else if (atype == ASSERT_NOTEQUAL)
9705 	ga_concat(gap, (char_u *)"Expected not equal to ");
9706     else
9707 	ga_concat(gap, (char_u *)"Expected ");
9708     if (exp_str == NULL)
9709     {
9710 	ga_concat_shorten_esc(gap, tv2string(exp_tv, &tofree, numbuf, 0));
9711 	vim_free(tofree);
9712     }
9713     else
9714 	ga_concat_shorten_esc(gap, exp_str);
9715     if (atype != ASSERT_NOTEQUAL)
9716     {
9717 	if (atype == ASSERT_MATCH)
9718 	    ga_concat(gap, (char_u *)" does not match ");
9719 	else if (atype == ASSERT_NOTMATCH)
9720 	    ga_concat(gap, (char_u *)" does match ");
9721 	else
9722 	    ga_concat(gap, (char_u *)" but got ");
9723 	ga_concat_shorten_esc(gap, tv2string(got_tv, &tofree, numbuf, 0));
9724 	vim_free(tofree);
9725     }
9726 }
9727 
9728 /*
9729  * Compare "typ1" and "typ2".  Put the result in "typ1".
9730  */
9731     int
9732 typval_compare(
9733     typval_T	*typ1,   /* first operand */
9734     typval_T	*typ2,   /* second operand */
9735     exptype_T	type,    /* operator */
9736     int		type_is, /* TRUE for "is" and "isnot" */
9737     int		ic)      /* ignore case */
9738 {
9739     int		i;
9740     varnumber_T	n1, n2;
9741     char_u	*s1, *s2;
9742     char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
9743 
9744     if (type_is && typ1->v_type != typ2->v_type)
9745     {
9746 	/* For "is" a different type always means FALSE, for "notis"
9747 	    * it means TRUE. */
9748 	n1 = (type == TYPE_NEQUAL);
9749     }
9750     else if (typ1->v_type == VAR_BLOB || typ2->v_type == VAR_BLOB)
9751     {
9752 	if (type_is)
9753 	{
9754 	    n1 = (typ1->v_type == typ2->v_type
9755 			    && typ1->vval.v_blob == typ2->vval.v_blob);
9756 	    if (type == TYPE_NEQUAL)
9757 		n1 = !n1;
9758 	}
9759 	else if (typ1->v_type != typ2->v_type
9760 		|| (type != TYPE_EQUAL && type != TYPE_NEQUAL))
9761 	{
9762 	    if (typ1->v_type != typ2->v_type)
9763 		emsg(_("E977: Can only compare Blob with Blob"));
9764 	    else
9765 		emsg(_(e_invalblob));
9766 	    clear_tv(typ1);
9767 	    return FAIL;
9768 	}
9769 	else
9770 	{
9771 	    // Compare two Blobs for being equal or unequal.
9772 	    n1 = blob_equal(typ1->vval.v_blob, typ2->vval.v_blob);
9773 	    if (type == TYPE_NEQUAL)
9774 		n1 = !n1;
9775 	}
9776     }
9777     else if (typ1->v_type == VAR_LIST || typ2->v_type == VAR_LIST)
9778     {
9779 	if (type_is)
9780 	{
9781 	    n1 = (typ1->v_type == typ2->v_type
9782 			    && typ1->vval.v_list == typ2->vval.v_list);
9783 	    if (type == TYPE_NEQUAL)
9784 		n1 = !n1;
9785 	}
9786 	else if (typ1->v_type != typ2->v_type
9787 		|| (type != TYPE_EQUAL && type != TYPE_NEQUAL))
9788 	{
9789 	    if (typ1->v_type != typ2->v_type)
9790 		emsg(_("E691: Can only compare List with List"));
9791 	    else
9792 		emsg(_("E692: Invalid operation for List"));
9793 	    clear_tv(typ1);
9794 	    return FAIL;
9795 	}
9796 	else
9797 	{
9798 	    /* Compare two Lists for being equal or unequal. */
9799 	    n1 = list_equal(typ1->vval.v_list, typ2->vval.v_list,
9800 							    ic, FALSE);
9801 	    if (type == TYPE_NEQUAL)
9802 		n1 = !n1;
9803 	}
9804     }
9805 
9806     else if (typ1->v_type == VAR_DICT || typ2->v_type == VAR_DICT)
9807     {
9808 	if (type_is)
9809 	{
9810 	    n1 = (typ1->v_type == typ2->v_type
9811 			    && typ1->vval.v_dict == typ2->vval.v_dict);
9812 	    if (type == TYPE_NEQUAL)
9813 		n1 = !n1;
9814 	}
9815 	else if (typ1->v_type != typ2->v_type
9816 		|| (type != TYPE_EQUAL && type != TYPE_NEQUAL))
9817 	{
9818 	    if (typ1->v_type != typ2->v_type)
9819 		emsg(_("E735: Can only compare Dictionary with Dictionary"));
9820 	    else
9821 		emsg(_("E736: Invalid operation for Dictionary"));
9822 	    clear_tv(typ1);
9823 	    return FAIL;
9824 	}
9825 	else
9826 	{
9827 	    /* Compare two Dictionaries for being equal or unequal. */
9828 	    n1 = dict_equal(typ1->vval.v_dict, typ2->vval.v_dict,
9829 							    ic, FALSE);
9830 	    if (type == TYPE_NEQUAL)
9831 		n1 = !n1;
9832 	}
9833     }
9834 
9835     else if (typ1->v_type == VAR_FUNC || typ2->v_type == VAR_FUNC
9836 	|| typ1->v_type == VAR_PARTIAL || typ2->v_type == VAR_PARTIAL)
9837     {
9838 	if (type != TYPE_EQUAL && type != TYPE_NEQUAL)
9839 	{
9840 	    emsg(_("E694: Invalid operation for Funcrefs"));
9841 	    clear_tv(typ1);
9842 	    return FAIL;
9843 	}
9844 	if ((typ1->v_type == VAR_PARTIAL
9845 					&& typ1->vval.v_partial == NULL)
9846 		|| (typ2->v_type == VAR_PARTIAL
9847 					&& typ2->vval.v_partial == NULL))
9848 	    /* when a partial is NULL assume not equal */
9849 	    n1 = FALSE;
9850 	else if (type_is)
9851 	{
9852 	    if (typ1->v_type == VAR_FUNC && typ2->v_type == VAR_FUNC)
9853 		/* strings are considered the same if their value is
9854 		    * the same */
9855 		n1 = tv_equal(typ1, typ2, ic, FALSE);
9856 	    else if (typ1->v_type == VAR_PARTIAL
9857 					&& typ2->v_type == VAR_PARTIAL)
9858 		n1 = (typ1->vval.v_partial == typ2->vval.v_partial);
9859 	    else
9860 		n1 = FALSE;
9861 	}
9862 	else
9863 	    n1 = tv_equal(typ1, typ2, ic, FALSE);
9864 	if (type == TYPE_NEQUAL)
9865 	    n1 = !n1;
9866     }
9867 
9868 #ifdef FEAT_FLOAT
9869     /*
9870 	* If one of the two variables is a float, compare as a float.
9871 	* When using "=~" or "!~", always compare as string.
9872 	*/
9873     else if ((typ1->v_type == VAR_FLOAT || typ2->v_type == VAR_FLOAT)
9874 	    && type != TYPE_MATCH && type != TYPE_NOMATCH)
9875     {
9876 	float_T f1, f2;
9877 
9878 	f1 = tv_get_float(typ1);
9879 	f2 = tv_get_float(typ2);
9880 	n1 = FALSE;
9881 	switch (type)
9882 	{
9883 	    case TYPE_EQUAL:    n1 = (f1 == f2); break;
9884 	    case TYPE_NEQUAL:   n1 = (f1 != f2); break;
9885 	    case TYPE_GREATER:  n1 = (f1 > f2); break;
9886 	    case TYPE_GEQUAL:   n1 = (f1 >= f2); break;
9887 	    case TYPE_SMALLER:  n1 = (f1 < f2); break;
9888 	    case TYPE_SEQUAL:   n1 = (f1 <= f2); break;
9889 	    case TYPE_UNKNOWN:
9890 	    case TYPE_MATCH:
9891 	    case TYPE_NOMATCH:  break;  /* avoid gcc warning */
9892 	}
9893     }
9894 #endif
9895 
9896     /*
9897 	* If one of the two variables is a number, compare as a number.
9898 	* When using "=~" or "!~", always compare as string.
9899 	*/
9900     else if ((typ1->v_type == VAR_NUMBER || typ2->v_type == VAR_NUMBER)
9901 	    && type != TYPE_MATCH && type != TYPE_NOMATCH)
9902     {
9903 	n1 = tv_get_number(typ1);
9904 	n2 = tv_get_number(typ2);
9905 	switch (type)
9906 	{
9907 	    case TYPE_EQUAL:    n1 = (n1 == n2); break;
9908 	    case TYPE_NEQUAL:   n1 = (n1 != n2); break;
9909 	    case TYPE_GREATER:  n1 = (n1 > n2); break;
9910 	    case TYPE_GEQUAL:   n1 = (n1 >= n2); break;
9911 	    case TYPE_SMALLER:  n1 = (n1 < n2); break;
9912 	    case TYPE_SEQUAL:   n1 = (n1 <= n2); break;
9913 	    case TYPE_UNKNOWN:
9914 	    case TYPE_MATCH:
9915 	    case TYPE_NOMATCH:  break;  /* avoid gcc warning */
9916 	}
9917     }
9918     else
9919     {
9920 	s1 = tv_get_string_buf(typ1, buf1);
9921 	s2 = tv_get_string_buf(typ2, buf2);
9922 	if (type != TYPE_MATCH && type != TYPE_NOMATCH)
9923 	    i = ic ? MB_STRICMP(s1, s2) : STRCMP(s1, s2);
9924 	else
9925 	    i = 0;
9926 	n1 = FALSE;
9927 	switch (type)
9928 	{
9929 	    case TYPE_EQUAL:    n1 = (i == 0); break;
9930 	    case TYPE_NEQUAL:   n1 = (i != 0); break;
9931 	    case TYPE_GREATER:  n1 = (i > 0); break;
9932 	    case TYPE_GEQUAL:   n1 = (i >= 0); break;
9933 	    case TYPE_SMALLER:  n1 = (i < 0); break;
9934 	    case TYPE_SEQUAL:   n1 = (i <= 0); break;
9935 
9936 	    case TYPE_MATCH:
9937 	    case TYPE_NOMATCH:
9938 		    n1 = pattern_match(s2, s1, ic);
9939 		    if (type == TYPE_NOMATCH)
9940 			n1 = !n1;
9941 		    break;
9942 
9943 	    case TYPE_UNKNOWN:  break;  /* avoid gcc warning */
9944 	}
9945     }
9946     clear_tv(typ1);
9947     typ1->v_type = VAR_NUMBER;
9948     typ1->vval.v_number = n1;
9949 
9950     return OK;
9951 }
9952 
9953     char_u *
9954 typval_tostring(typval_T *arg)
9955 {
9956     char_u	*tofree;
9957     char_u	numbuf[NUMBUFLEN];
9958     char_u	*ret = NULL;
9959 
9960     if (arg == NULL)
9961 	return vim_strsave((char_u *)"(does not exist)");
9962     ret = tv2string(arg, &tofree, numbuf, 0);
9963     /* Make a copy if we have a value but it's not in allocated memory. */
9964     if (ret != NULL && tofree == NULL)
9965 	ret = vim_strsave(ret);
9966     return ret;
9967 }
9968 
9969     int
9970 var_exists(char_u *var)
9971 {
9972     char_u	*name;
9973     char_u	*tofree;
9974     typval_T    tv;
9975     int		len = 0;
9976     int		n = FALSE;
9977 
9978     /* get_name_len() takes care of expanding curly braces */
9979     name = var;
9980     len = get_name_len(&var, &tofree, TRUE, FALSE);
9981     if (len > 0)
9982     {
9983 	if (tofree != NULL)
9984 	    name = tofree;
9985 	n = (get_var_tv(name, len, &tv, NULL, FALSE, TRUE) == OK);
9986 	if (n)
9987 	{
9988 	    /* handle d.key, l[idx], f(expr) */
9989 	    n = (handle_subscript(&var, &tv, TRUE, FALSE) == OK);
9990 	    if (n)
9991 		clear_tv(&tv);
9992 	}
9993     }
9994     if (*var != NUL)
9995 	n = FALSE;
9996 
9997     vim_free(tofree);
9998     return n;
9999 }
10000 
10001 #endif /* FEAT_EVAL */
10002 
10003 
10004 #if defined(FEAT_MODIFY_FNAME) || defined(FEAT_EVAL) || defined(PROTO)
10005 
10006 #ifdef MSWIN
10007 /*
10008  * Functions for ":8" filename modifier: get 8.3 version of a filename.
10009  */
10010 
10011 /*
10012  * Get the short path (8.3) for the filename in "fnamep".
10013  * Only works for a valid file name.
10014  * When the path gets longer "fnamep" is changed and the allocated buffer
10015  * is put in "bufp".
10016  * *fnamelen is the length of "fnamep" and set to 0 for a nonexistent path.
10017  * Returns OK on success, FAIL on failure.
10018  */
10019     static int
10020 get_short_pathname(char_u **fnamep, char_u **bufp, int *fnamelen)
10021 {
10022     int		l, len;
10023     char_u	*newbuf;
10024 
10025     len = *fnamelen;
10026     l = GetShortPathName((LPSTR)*fnamep, (LPSTR)*fnamep, len);
10027     if (l > len - 1)
10028     {
10029 	/* If that doesn't work (not enough space), then save the string
10030 	 * and try again with a new buffer big enough. */
10031 	newbuf = vim_strnsave(*fnamep, l);
10032 	if (newbuf == NULL)
10033 	    return FAIL;
10034 
10035 	vim_free(*bufp);
10036 	*fnamep = *bufp = newbuf;
10037 
10038 	/* Really should always succeed, as the buffer is big enough. */
10039 	l = GetShortPathName((LPSTR)*fnamep, (LPSTR)*fnamep, l+1);
10040     }
10041 
10042     *fnamelen = l;
10043     return OK;
10044 }
10045 
10046 /*
10047  * Get the short path (8.3) for the filename in "fname". The converted
10048  * path is returned in "bufp".
10049  *
10050  * Some of the directories specified in "fname" may not exist. This function
10051  * will shorten the existing directories at the beginning of the path and then
10052  * append the remaining non-existing path.
10053  *
10054  * fname - Pointer to the filename to shorten.  On return, contains the
10055  *	   pointer to the shortened pathname
10056  * bufp -  Pointer to an allocated buffer for the filename.
10057  * fnamelen - Length of the filename pointed to by fname
10058  *
10059  * Returns OK on success (or nothing done) and FAIL on failure (out of memory).
10060  */
10061     static int
10062 shortpath_for_invalid_fname(
10063     char_u	**fname,
10064     char_u	**bufp,
10065     int		*fnamelen)
10066 {
10067     char_u	*short_fname, *save_fname, *pbuf_unused;
10068     char_u	*endp, *save_endp;
10069     char_u	ch;
10070     int		old_len, len;
10071     int		new_len, sfx_len;
10072     int		retval = OK;
10073 
10074     /* Make a copy */
10075     old_len = *fnamelen;
10076     save_fname = vim_strnsave(*fname, old_len);
10077     pbuf_unused = NULL;
10078     short_fname = NULL;
10079 
10080     endp = save_fname + old_len - 1; /* Find the end of the copy */
10081     save_endp = endp;
10082 
10083     /*
10084      * Try shortening the supplied path till it succeeds by removing one
10085      * directory at a time from the tail of the path.
10086      */
10087     len = 0;
10088     for (;;)
10089     {
10090 	/* go back one path-separator */
10091 	while (endp > save_fname && !after_pathsep(save_fname, endp + 1))
10092 	    --endp;
10093 	if (endp <= save_fname)
10094 	    break;		/* processed the complete path */
10095 
10096 	/*
10097 	 * Replace the path separator with a NUL and try to shorten the
10098 	 * resulting path.
10099 	 */
10100 	ch = *endp;
10101 	*endp = 0;
10102 	short_fname = save_fname;
10103 	len = (int)STRLEN(short_fname) + 1;
10104 	if (get_short_pathname(&short_fname, &pbuf_unused, &len) == FAIL)
10105 	{
10106 	    retval = FAIL;
10107 	    goto theend;
10108 	}
10109 	*endp = ch;	/* preserve the string */
10110 
10111 	if (len > 0)
10112 	    break;	/* successfully shortened the path */
10113 
10114 	/* failed to shorten the path. Skip the path separator */
10115 	--endp;
10116     }
10117 
10118     if (len > 0)
10119     {
10120 	/*
10121 	 * Succeeded in shortening the path. Now concatenate the shortened
10122 	 * path with the remaining path at the tail.
10123 	 */
10124 
10125 	/* Compute the length of the new path. */
10126 	sfx_len = (int)(save_endp - endp) + 1;
10127 	new_len = len + sfx_len;
10128 
10129 	*fnamelen = new_len;
10130 	vim_free(*bufp);
10131 	if (new_len > old_len)
10132 	{
10133 	    /* There is not enough space in the currently allocated string,
10134 	     * copy it to a buffer big enough. */
10135 	    *fname = *bufp = vim_strnsave(short_fname, new_len);
10136 	    if (*fname == NULL)
10137 	    {
10138 		retval = FAIL;
10139 		goto theend;
10140 	    }
10141 	}
10142 	else
10143 	{
10144 	    /* Transfer short_fname to the main buffer (it's big enough),
10145 	     * unless get_short_pathname() did its work in-place. */
10146 	    *fname = *bufp = save_fname;
10147 	    if (short_fname != save_fname)
10148 		vim_strncpy(save_fname, short_fname, len);
10149 	    save_fname = NULL;
10150 	}
10151 
10152 	/* concat the not-shortened part of the path */
10153 	vim_strncpy(*fname + len, endp, sfx_len);
10154 	(*fname)[new_len] = NUL;
10155     }
10156 
10157 theend:
10158     vim_free(pbuf_unused);
10159     vim_free(save_fname);
10160 
10161     return retval;
10162 }
10163 
10164 /*
10165  * Get a pathname for a partial path.
10166  * Returns OK for success, FAIL for failure.
10167  */
10168     static int
10169 shortpath_for_partial(
10170     char_u	**fnamep,
10171     char_u	**bufp,
10172     int		*fnamelen)
10173 {
10174     int		sepcount, len, tflen;
10175     char_u	*p;
10176     char_u	*pbuf, *tfname;
10177     int		hasTilde;
10178 
10179     /* Count up the path separators from the RHS.. so we know which part
10180      * of the path to return. */
10181     sepcount = 0;
10182     for (p = *fnamep; p < *fnamep + *fnamelen; MB_PTR_ADV(p))
10183 	if (vim_ispathsep(*p))
10184 	    ++sepcount;
10185 
10186     /* Need full path first (use expand_env() to remove a "~/") */
10187     hasTilde = (**fnamep == '~');
10188     if (hasTilde)
10189 	pbuf = tfname = expand_env_save(*fnamep);
10190     else
10191 	pbuf = tfname = FullName_save(*fnamep, FALSE);
10192 
10193     len = tflen = (int)STRLEN(tfname);
10194 
10195     if (get_short_pathname(&tfname, &pbuf, &len) == FAIL)
10196 	return FAIL;
10197 
10198     if (len == 0)
10199     {
10200 	/* Don't have a valid filename, so shorten the rest of the
10201 	 * path if we can. This CAN give us invalid 8.3 filenames, but
10202 	 * there's not a lot of point in guessing what it might be.
10203 	 */
10204 	len = tflen;
10205 	if (shortpath_for_invalid_fname(&tfname, &pbuf, &len) == FAIL)
10206 	    return FAIL;
10207     }
10208 
10209     /* Count the paths backward to find the beginning of the desired string. */
10210     for (p = tfname + len - 1; p >= tfname; --p)
10211     {
10212 	if (has_mbyte)
10213 	    p -= mb_head_off(tfname, p);
10214 	if (vim_ispathsep(*p))
10215 	{
10216 	    if (sepcount == 0 || (hasTilde && sepcount == 1))
10217 		break;
10218 	    else
10219 		sepcount --;
10220 	}
10221     }
10222     if (hasTilde)
10223     {
10224 	--p;
10225 	if (p >= tfname)
10226 	    *p = '~';
10227 	else
10228 	    return FAIL;
10229     }
10230     else
10231 	++p;
10232 
10233     /* Copy in the string - p indexes into tfname - allocated at pbuf */
10234     vim_free(*bufp);
10235     *fnamelen = (int)STRLEN(p);
10236     *bufp = pbuf;
10237     *fnamep = p;
10238 
10239     return OK;
10240 }
10241 #endif // MSWIN
10242 
10243 /*
10244  * Adjust a filename, according to a string of modifiers.
10245  * *fnamep must be NUL terminated when called.  When returning, the length is
10246  * determined by *fnamelen.
10247  * Returns VALID_ flags or -1 for failure.
10248  * When there is an error, *fnamep is set to NULL.
10249  */
10250     int
10251 modify_fname(
10252     char_u	*src,		// string with modifiers
10253     int		tilde_file,	// "~" is a file name, not $HOME
10254     int		*usedlen,	// characters after src that are used
10255     char_u	**fnamep,	// file name so far
10256     char_u	**bufp,		// buffer for allocated file name or NULL
10257     int		*fnamelen)	// length of fnamep
10258 {
10259     int		valid = 0;
10260     char_u	*tail;
10261     char_u	*s, *p, *pbuf;
10262     char_u	dirname[MAXPATHL];
10263     int		c;
10264     int		has_fullname = 0;
10265 #ifdef MSWIN
10266     char_u	*fname_start = *fnamep;
10267     int		has_shortname = 0;
10268 #endif
10269 
10270 repeat:
10271     /* ":p" - full path/file_name */
10272     if (src[*usedlen] == ':' && src[*usedlen + 1] == 'p')
10273     {
10274 	has_fullname = 1;
10275 
10276 	valid |= VALID_PATH;
10277 	*usedlen += 2;
10278 
10279 	/* Expand "~/path" for all systems and "~user/path" for Unix and VMS */
10280 	if ((*fnamep)[0] == '~'
10281 #if !defined(UNIX) && !(defined(VMS) && defined(USER_HOME))
10282 		&& ((*fnamep)[1] == '/'
10283 # ifdef BACKSLASH_IN_FILENAME
10284 		    || (*fnamep)[1] == '\\'
10285 # endif
10286 		    || (*fnamep)[1] == NUL)
10287 #endif
10288 		&& !(tilde_file && (*fnamep)[1] == NUL)
10289 	   )
10290 	{
10291 	    *fnamep = expand_env_save(*fnamep);
10292 	    vim_free(*bufp);	/* free any allocated file name */
10293 	    *bufp = *fnamep;
10294 	    if (*fnamep == NULL)
10295 		return -1;
10296 	}
10297 
10298 	/* When "/." or "/.." is used: force expansion to get rid of it. */
10299 	for (p = *fnamep; *p != NUL; MB_PTR_ADV(p))
10300 	{
10301 	    if (vim_ispathsep(*p)
10302 		    && p[1] == '.'
10303 		    && (p[2] == NUL
10304 			|| vim_ispathsep(p[2])
10305 			|| (p[2] == '.'
10306 			    && (p[3] == NUL || vim_ispathsep(p[3])))))
10307 		break;
10308 	}
10309 
10310 	/* FullName_save() is slow, don't use it when not needed. */
10311 	if (*p != NUL || !vim_isAbsName(*fnamep))
10312 	{
10313 	    *fnamep = FullName_save(*fnamep, *p != NUL);
10314 	    vim_free(*bufp);	/* free any allocated file name */
10315 	    *bufp = *fnamep;
10316 	    if (*fnamep == NULL)
10317 		return -1;
10318 	}
10319 
10320 #ifdef MSWIN
10321 # if _WIN32_WINNT >= 0x0500
10322 	if (vim_strchr(*fnamep, '~') != NULL)
10323 	{
10324 	    /* Expand 8.3 filename to full path.  Needed to make sure the same
10325 	     * file does not have two different names.
10326 	     * Note: problem does not occur if _WIN32_WINNT < 0x0500. */
10327 	    p = alloc(_MAX_PATH + 1);
10328 	    if (p != NULL)
10329 	    {
10330 		if (GetLongPathName((LPSTR)*fnamep, (LPSTR)p, _MAX_PATH))
10331 		{
10332 		    vim_free(*bufp);
10333 		    *bufp = *fnamep = p;
10334 		}
10335 		else
10336 		    vim_free(p);
10337 	    }
10338 	}
10339 # endif
10340 #endif
10341 	/* Append a path separator to a directory. */
10342 	if (mch_isdir(*fnamep))
10343 	{
10344 	    /* Make room for one or two extra characters. */
10345 	    *fnamep = vim_strnsave(*fnamep, (int)STRLEN(*fnamep) + 2);
10346 	    vim_free(*bufp);	/* free any allocated file name */
10347 	    *bufp = *fnamep;
10348 	    if (*fnamep == NULL)
10349 		return -1;
10350 	    add_pathsep(*fnamep);
10351 	}
10352     }
10353 
10354     /* ":." - path relative to the current directory */
10355     /* ":~" - path relative to the home directory */
10356     /* ":8" - shortname path - postponed till after */
10357     while (src[*usedlen] == ':'
10358 		  && ((c = src[*usedlen + 1]) == '.' || c == '~' || c == '8'))
10359     {
10360 	*usedlen += 2;
10361 	if (c == '8')
10362 	{
10363 #ifdef MSWIN
10364 	    has_shortname = 1; /* Postpone this. */
10365 #endif
10366 	    continue;
10367 	}
10368 	pbuf = NULL;
10369 	/* Need full path first (use expand_env() to remove a "~/") */
10370 	if (!has_fullname)
10371 	{
10372 	    if (c == '.' && **fnamep == '~')
10373 		p = pbuf = expand_env_save(*fnamep);
10374 	    else
10375 		p = pbuf = FullName_save(*fnamep, FALSE);
10376 	}
10377 	else
10378 	    p = *fnamep;
10379 
10380 	has_fullname = 0;
10381 
10382 	if (p != NULL)
10383 	{
10384 	    if (c == '.')
10385 	    {
10386 		mch_dirname(dirname, MAXPATHL);
10387 		s = shorten_fname(p, dirname);
10388 		if (s != NULL)
10389 		{
10390 		    *fnamep = s;
10391 		    if (pbuf != NULL)
10392 		    {
10393 			vim_free(*bufp);   /* free any allocated file name */
10394 			*bufp = pbuf;
10395 			pbuf = NULL;
10396 		    }
10397 		}
10398 	    }
10399 	    else
10400 	    {
10401 		home_replace(NULL, p, dirname, MAXPATHL, TRUE);
10402 		/* Only replace it when it starts with '~' */
10403 		if (*dirname == '~')
10404 		{
10405 		    s = vim_strsave(dirname);
10406 		    if (s != NULL)
10407 		    {
10408 			*fnamep = s;
10409 			vim_free(*bufp);
10410 			*bufp = s;
10411 		    }
10412 		}
10413 	    }
10414 	    vim_free(pbuf);
10415 	}
10416     }
10417 
10418     tail = gettail(*fnamep);
10419     *fnamelen = (int)STRLEN(*fnamep);
10420 
10421     /* ":h" - head, remove "/file_name", can be repeated  */
10422     /* Don't remove the first "/" or "c:\" */
10423     while (src[*usedlen] == ':' && src[*usedlen + 1] == 'h')
10424     {
10425 	valid |= VALID_HEAD;
10426 	*usedlen += 2;
10427 	s = get_past_head(*fnamep);
10428 	while (tail > s && after_pathsep(s, tail))
10429 	    MB_PTR_BACK(*fnamep, tail);
10430 	*fnamelen = (int)(tail - *fnamep);
10431 #ifdef VMS
10432 	if (*fnamelen > 0)
10433 	    *fnamelen += 1; /* the path separator is part of the path */
10434 #endif
10435 	if (*fnamelen == 0)
10436 	{
10437 	    /* Result is empty.  Turn it into "." to make ":cd %:h" work. */
10438 	    p = vim_strsave((char_u *)".");
10439 	    if (p == NULL)
10440 		return -1;
10441 	    vim_free(*bufp);
10442 	    *bufp = *fnamep = tail = p;
10443 	    *fnamelen = 1;
10444 	}
10445 	else
10446 	{
10447 	    while (tail > s && !after_pathsep(s, tail))
10448 		MB_PTR_BACK(*fnamep, tail);
10449 	}
10450     }
10451 
10452     /* ":8" - shortname  */
10453     if (src[*usedlen] == ':' && src[*usedlen + 1] == '8')
10454     {
10455 	*usedlen += 2;
10456 #ifdef MSWIN
10457 	has_shortname = 1;
10458 #endif
10459     }
10460 
10461 #ifdef MSWIN
10462     /*
10463      * Handle ":8" after we have done 'heads' and before we do 'tails'.
10464      */
10465     if (has_shortname)
10466     {
10467 	/* Copy the string if it is shortened by :h and when it wasn't copied
10468 	 * yet, because we are going to change it in place.  Avoids changing
10469 	 * the buffer name for "%:8". */
10470 	if (*fnamelen < (int)STRLEN(*fnamep) || *fnamep == fname_start)
10471 	{
10472 	    p = vim_strnsave(*fnamep, *fnamelen);
10473 	    if (p == NULL)
10474 		return -1;
10475 	    vim_free(*bufp);
10476 	    *bufp = *fnamep = p;
10477 	}
10478 
10479 	/* Split into two implementations - makes it easier.  First is where
10480 	 * there isn't a full name already, second is where there is. */
10481 	if (!has_fullname && !vim_isAbsName(*fnamep))
10482 	{
10483 	    if (shortpath_for_partial(fnamep, bufp, fnamelen) == FAIL)
10484 		return -1;
10485 	}
10486 	else
10487 	{
10488 	    int		l = *fnamelen;
10489 
10490 	    /* Simple case, already have the full-name.
10491 	     * Nearly always shorter, so try first time. */
10492 	    if (get_short_pathname(fnamep, bufp, &l) == FAIL)
10493 		return -1;
10494 
10495 	    if (l == 0)
10496 	    {
10497 		/* Couldn't find the filename, search the paths. */
10498 		l = *fnamelen;
10499 		if (shortpath_for_invalid_fname(fnamep, bufp, &l) == FAIL)
10500 		    return -1;
10501 	    }
10502 	    *fnamelen = l;
10503 	}
10504     }
10505 #endif // MSWIN
10506 
10507     /* ":t" - tail, just the basename */
10508     if (src[*usedlen] == ':' && src[*usedlen + 1] == 't')
10509     {
10510 	*usedlen += 2;
10511 	*fnamelen -= (int)(tail - *fnamep);
10512 	*fnamep = tail;
10513     }
10514 
10515     /* ":e" - extension, can be repeated */
10516     /* ":r" - root, without extension, can be repeated */
10517     while (src[*usedlen] == ':'
10518 	    && (src[*usedlen + 1] == 'e' || src[*usedlen + 1] == 'r'))
10519     {
10520 	/* find a '.' in the tail:
10521 	 * - for second :e: before the current fname
10522 	 * - otherwise: The last '.'
10523 	 */
10524 	if (src[*usedlen + 1] == 'e' && *fnamep > tail)
10525 	    s = *fnamep - 2;
10526 	else
10527 	    s = *fnamep + *fnamelen - 1;
10528 	for ( ; s > tail; --s)
10529 	    if (s[0] == '.')
10530 		break;
10531 	if (src[*usedlen + 1] == 'e')		/* :e */
10532 	{
10533 	    if (s > tail)
10534 	    {
10535 		*fnamelen += (int)(*fnamep - (s + 1));
10536 		*fnamep = s + 1;
10537 #ifdef VMS
10538 		/* cut version from the extension */
10539 		s = *fnamep + *fnamelen - 1;
10540 		for ( ; s > *fnamep; --s)
10541 		    if (s[0] == ';')
10542 			break;
10543 		if (s > *fnamep)
10544 		    *fnamelen = s - *fnamep;
10545 #endif
10546 	    }
10547 	    else if (*fnamep <= tail)
10548 		*fnamelen = 0;
10549 	}
10550 	else				/* :r */
10551 	{
10552 	    if (s > tail)	/* remove one extension */
10553 		*fnamelen = (int)(s - *fnamep);
10554 	}
10555 	*usedlen += 2;
10556     }
10557 
10558     /* ":s?pat?foo?" - substitute */
10559     /* ":gs?pat?foo?" - global substitute */
10560     if (src[*usedlen] == ':'
10561 	    && (src[*usedlen + 1] == 's'
10562 		|| (src[*usedlen + 1] == 'g' && src[*usedlen + 2] == 's')))
10563     {
10564 	char_u	    *str;
10565 	char_u	    *pat;
10566 	char_u	    *sub;
10567 	int	    sep;
10568 	char_u	    *flags;
10569 	int	    didit = FALSE;
10570 
10571 	flags = (char_u *)"";
10572 	s = src + *usedlen + 2;
10573 	if (src[*usedlen + 1] == 'g')
10574 	{
10575 	    flags = (char_u *)"g";
10576 	    ++s;
10577 	}
10578 
10579 	sep = *s++;
10580 	if (sep)
10581 	{
10582 	    /* find end of pattern */
10583 	    p = vim_strchr(s, sep);
10584 	    if (p != NULL)
10585 	    {
10586 		pat = vim_strnsave(s, (int)(p - s));
10587 		if (pat != NULL)
10588 		{
10589 		    s = p + 1;
10590 		    /* find end of substitution */
10591 		    p = vim_strchr(s, sep);
10592 		    if (p != NULL)
10593 		    {
10594 			sub = vim_strnsave(s, (int)(p - s));
10595 			str = vim_strnsave(*fnamep, *fnamelen);
10596 			if (sub != NULL && str != NULL)
10597 			{
10598 			    *usedlen = (int)(p + 1 - src);
10599 			    s = do_string_sub(str, pat, sub, NULL, flags);
10600 			    if (s != NULL)
10601 			    {
10602 				*fnamep = s;
10603 				*fnamelen = (int)STRLEN(s);
10604 				vim_free(*bufp);
10605 				*bufp = s;
10606 				didit = TRUE;
10607 			    }
10608 			}
10609 			vim_free(sub);
10610 			vim_free(str);
10611 		    }
10612 		    vim_free(pat);
10613 		}
10614 	    }
10615 	    /* after using ":s", repeat all the modifiers */
10616 	    if (didit)
10617 		goto repeat;
10618 	}
10619     }
10620 
10621     if (src[*usedlen] == ':' && src[*usedlen + 1] == 'S')
10622     {
10623 	/* vim_strsave_shellescape() needs a NUL terminated string. */
10624 	c = (*fnamep)[*fnamelen];
10625 	if (c != NUL)
10626 	    (*fnamep)[*fnamelen] = NUL;
10627 	p = vim_strsave_shellescape(*fnamep, FALSE, FALSE);
10628 	if (c != NUL)
10629 	    (*fnamep)[*fnamelen] = c;
10630 	if (p == NULL)
10631 	    return -1;
10632 	vim_free(*bufp);
10633 	*bufp = *fnamep = p;
10634 	*fnamelen = (int)STRLEN(p);
10635 	*usedlen += 2;
10636     }
10637 
10638     return valid;
10639 }
10640 
10641 /*
10642  * Perform a substitution on "str" with pattern "pat" and substitute "sub".
10643  * When "sub" is NULL "expr" is used, must be a VAR_FUNC or VAR_PARTIAL.
10644  * "flags" can be "g" to do a global substitute.
10645  * Returns an allocated string, NULL for error.
10646  */
10647     char_u *
10648 do_string_sub(
10649     char_u	*str,
10650     char_u	*pat,
10651     char_u	*sub,
10652     typval_T	*expr,
10653     char_u	*flags)
10654 {
10655     int		sublen;
10656     regmatch_T	regmatch;
10657     int		i;
10658     int		do_all;
10659     char_u	*tail;
10660     char_u	*end;
10661     garray_T	ga;
10662     char_u	*ret;
10663     char_u	*save_cpo;
10664     char_u	*zero_width = NULL;
10665 
10666     /* Make 'cpoptions' empty, so that the 'l' flag doesn't work here */
10667     save_cpo = p_cpo;
10668     p_cpo = empty_option;
10669 
10670     ga_init2(&ga, 1, 200);
10671 
10672     do_all = (flags[0] == 'g');
10673 
10674     regmatch.rm_ic = p_ic;
10675     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
10676     if (regmatch.regprog != NULL)
10677     {
10678 	tail = str;
10679 	end = str + STRLEN(str);
10680 	while (vim_regexec_nl(&regmatch, str, (colnr_T)(tail - str)))
10681 	{
10682 	    /* Skip empty match except for first match. */
10683 	    if (regmatch.startp[0] == regmatch.endp[0])
10684 	    {
10685 		if (zero_width == regmatch.startp[0])
10686 		{
10687 		    /* avoid getting stuck on a match with an empty string */
10688 		    i = MB_PTR2LEN(tail);
10689 		    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail,
10690 								   (size_t)i);
10691 		    ga.ga_len += i;
10692 		    tail += i;
10693 		    continue;
10694 		}
10695 		zero_width = regmatch.startp[0];
10696 	    }
10697 
10698 	    /*
10699 	     * Get some space for a temporary buffer to do the substitution
10700 	     * into.  It will contain:
10701 	     * - The text up to where the match is.
10702 	     * - The substituted text.
10703 	     * - The text after the match.
10704 	     */
10705 	    sublen = vim_regsub(&regmatch, sub, expr, tail, FALSE, TRUE, FALSE);
10706 	    if (ga_grow(&ga, (int)((end - tail) + sublen -
10707 			    (regmatch.endp[0] - regmatch.startp[0]))) == FAIL)
10708 	    {
10709 		ga_clear(&ga);
10710 		break;
10711 	    }
10712 
10713 	    /* copy the text up to where the match is */
10714 	    i = (int)(regmatch.startp[0] - tail);
10715 	    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail, (size_t)i);
10716 	    /* add the substituted text */
10717 	    (void)vim_regsub(&regmatch, sub, expr, (char_u *)ga.ga_data
10718 					  + ga.ga_len + i, TRUE, TRUE, FALSE);
10719 	    ga.ga_len += i + sublen - 1;
10720 	    tail = regmatch.endp[0];
10721 	    if (*tail == NUL)
10722 		break;
10723 	    if (!do_all)
10724 		break;
10725 	}
10726 
10727 	if (ga.ga_data != NULL)
10728 	    STRCPY((char *)ga.ga_data + ga.ga_len, tail);
10729 
10730 	vim_regfree(regmatch.regprog);
10731     }
10732 
10733     ret = vim_strsave(ga.ga_data == NULL ? str : (char_u *)ga.ga_data);
10734     ga_clear(&ga);
10735     if (p_cpo == empty_option)
10736 	p_cpo = save_cpo;
10737     else
10738 	/* Darn, evaluating {sub} expression or {expr} changed the value. */
10739 	free_string_option(save_cpo);
10740 
10741     return ret;
10742 }
10743 
10744     static int
10745 filter_map_one(typval_T *tv, typval_T *expr, int map, int *remp)
10746 {
10747     typval_T	rettv;
10748     typval_T	argv[3];
10749     int		retval = FAIL;
10750 
10751     copy_tv(tv, &vimvars[VV_VAL].vv_tv);
10752     argv[0] = vimvars[VV_KEY].vv_tv;
10753     argv[1] = vimvars[VV_VAL].vv_tv;
10754     if (eval_expr_typval(expr, argv, 2, &rettv) == FAIL)
10755 	goto theend;
10756     if (map)
10757     {
10758 	/* map(): replace the list item value */
10759 	clear_tv(tv);
10760 	rettv.v_lock = 0;
10761 	*tv = rettv;
10762     }
10763     else
10764     {
10765 	int	    error = FALSE;
10766 
10767 	/* filter(): when expr is zero remove the item */
10768 	*remp = (tv_get_number_chk(&rettv, &error) == 0);
10769 	clear_tv(&rettv);
10770 	/* On type error, nothing has been removed; return FAIL to stop the
10771 	 * loop.  The error message was given by tv_get_number_chk(). */
10772 	if (error)
10773 	    goto theend;
10774     }
10775     retval = OK;
10776 theend:
10777     clear_tv(&vimvars[VV_VAL].vv_tv);
10778     return retval;
10779 }
10780 
10781 
10782 /*
10783  * Implementation of map() and filter().
10784  */
10785     void
10786 filter_map(typval_T *argvars, typval_T *rettv, int map)
10787 {
10788     typval_T	*expr;
10789     listitem_T	*li, *nli;
10790     list_T	*l = NULL;
10791     dictitem_T	*di;
10792     hashtab_T	*ht;
10793     hashitem_T	*hi;
10794     dict_T	*d = NULL;
10795     typval_T	save_val;
10796     typval_T	save_key;
10797     blob_T	*b = NULL;
10798     int		rem;
10799     int		todo;
10800     char_u	*ermsg = (char_u *)(map ? "map()" : "filter()");
10801     char_u	*arg_errmsg = (char_u *)(map ? N_("map() argument")
10802 				   : N_("filter() argument"));
10803     int		save_did_emsg;
10804     int		idx = 0;
10805 
10806     if (argvars[0].v_type == VAR_BLOB)
10807     {
10808 	if ((b = argvars[0].vval.v_blob) == NULL)
10809 	    return;
10810     }
10811     else if (argvars[0].v_type == VAR_LIST)
10812     {
10813 	if ((l = argvars[0].vval.v_list) == NULL
10814 	      || (!map && var_check_lock(l->lv_lock, arg_errmsg, TRUE)))
10815 	    return;
10816     }
10817     else if (argvars[0].v_type == VAR_DICT)
10818     {
10819 	if ((d = argvars[0].vval.v_dict) == NULL
10820 	      || (!map && var_check_lock(d->dv_lock, arg_errmsg, TRUE)))
10821 	    return;
10822     }
10823     else
10824     {
10825 	semsg(_(e_listdictarg), ermsg);
10826 	return;
10827     }
10828 
10829     expr = &argvars[1];
10830     /* On type errors, the preceding call has already displayed an error
10831      * message.  Avoid a misleading error message for an empty string that
10832      * was not passed as argument. */
10833     if (expr->v_type != VAR_UNKNOWN)
10834     {
10835 	prepare_vimvar(VV_VAL, &save_val);
10836 
10837 	/* We reset "did_emsg" to be able to detect whether an error
10838 	 * occurred during evaluation of the expression. */
10839 	save_did_emsg = did_emsg;
10840 	did_emsg = FALSE;
10841 
10842 	prepare_vimvar(VV_KEY, &save_key);
10843 	if (argvars[0].v_type == VAR_DICT)
10844 	{
10845 	    vimvars[VV_KEY].vv_type = VAR_STRING;
10846 
10847 	    ht = &d->dv_hashtab;
10848 	    hash_lock(ht);
10849 	    todo = (int)ht->ht_used;
10850 	    for (hi = ht->ht_array; todo > 0; ++hi)
10851 	    {
10852 		if (!HASHITEM_EMPTY(hi))
10853 		{
10854 		    int r;
10855 
10856 		    --todo;
10857 		    di = HI2DI(hi);
10858 		    if (map && (var_check_lock(di->di_tv.v_lock,
10859 							   arg_errmsg, TRUE)
10860 				|| var_check_ro(di->di_flags,
10861 							   arg_errmsg, TRUE)))
10862 			break;
10863 		    vimvars[VV_KEY].vv_str = vim_strsave(di->di_key);
10864 		    r = filter_map_one(&di->di_tv, expr, map, &rem);
10865 		    clear_tv(&vimvars[VV_KEY].vv_tv);
10866 		    if (r == FAIL || did_emsg)
10867 			break;
10868 		    if (!map && rem)
10869 		    {
10870 			if (var_check_fixed(di->di_flags, arg_errmsg, TRUE)
10871 			    || var_check_ro(di->di_flags, arg_errmsg, TRUE))
10872 			    break;
10873 			dictitem_remove(d, di);
10874 		    }
10875 		}
10876 	    }
10877 	    hash_unlock(ht);
10878 	}
10879 	else if (argvars[0].v_type == VAR_BLOB)
10880 	{
10881 	    int		i;
10882 	    typval_T	tv;
10883 
10884 	    vimvars[VV_KEY].vv_type = VAR_NUMBER;
10885 	    for (i = 0; i < b->bv_ga.ga_len; i++)
10886 	    {
10887 		tv.v_type = VAR_NUMBER;
10888 		tv.vval.v_number = blob_get(b, i);
10889 		vimvars[VV_KEY].vv_nr = idx;
10890 		if (filter_map_one(&tv, expr, map, &rem) == FAIL || did_emsg)
10891 		    break;
10892 		if (tv.v_type != VAR_NUMBER)
10893 		{
10894 		    emsg(_(e_invalblob));
10895 		    return;
10896 		}
10897 		tv.v_type = VAR_NUMBER;
10898 		blob_set(b, i, tv.vval.v_number);
10899 		if (!map && rem)
10900 		{
10901 		    char_u *p = (char_u *)argvars[0].vval.v_blob->bv_ga.ga_data;
10902 
10903 		    mch_memmove(p + idx, p + i + 1,
10904 					      (size_t)b->bv_ga.ga_len - i - 1);
10905 		    --b->bv_ga.ga_len;
10906 		    --i;
10907 		}
10908 	    }
10909 	}
10910 	else
10911 	{
10912 	    // argvars[0].v_type == VAR_LIST
10913 	    vimvars[VV_KEY].vv_type = VAR_NUMBER;
10914 
10915 	    for (li = l->lv_first; li != NULL; li = nli)
10916 	    {
10917 		if (map && var_check_lock(li->li_tv.v_lock, arg_errmsg, TRUE))
10918 		    break;
10919 		nli = li->li_next;
10920 		vimvars[VV_KEY].vv_nr = idx;
10921 		if (filter_map_one(&li->li_tv, expr, map, &rem) == FAIL
10922 								  || did_emsg)
10923 		    break;
10924 		if (!map && rem)
10925 		    listitem_remove(l, li);
10926 		++idx;
10927 	    }
10928 	}
10929 
10930 	restore_vimvar(VV_KEY, &save_key);
10931 	restore_vimvar(VV_VAL, &save_val);
10932 
10933 	did_emsg |= save_did_emsg;
10934     }
10935 
10936     copy_tv(&argvars[0], rettv);
10937 }
10938 
10939 #endif /* defined(FEAT_MODIFY_FNAME) || defined(FEAT_EVAL) */
10940