xref: /vim-8.2.3635/src/eval.c (revision 493fbe4a)
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 	}
2212 	else
2213 	{
2214 	    /*
2215 	     * Get the number and item for the only or first index of the List.
2216 	     */
2217 	    if (empty1)
2218 		lp->ll_n1 = 0;
2219 	    else
2220 		/* is number or string */
2221 		lp->ll_n1 = (long)tv_get_number(&var1);
2222 	    clear_tv(&var1);
2223 
2224 	    lp->ll_dict = NULL;
2225 	    lp->ll_list = lp->ll_tv->vval.v_list;
2226 	    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
2227 	    if (lp->ll_li == NULL)
2228 	    {
2229 		if (lp->ll_n1 < 0)
2230 		{
2231 		    lp->ll_n1 = 0;
2232 		    lp->ll_li = list_find(lp->ll_list, lp->ll_n1);
2233 		}
2234 	    }
2235 	    if (lp->ll_li == NULL)
2236 	    {
2237 		clear_tv(&var2);
2238 		if (!quiet)
2239 		    semsg(_(e_listidx), lp->ll_n1);
2240 		return NULL;
2241 	    }
2242 
2243 	    /*
2244 	     * May need to find the item or absolute index for the second
2245 	     * index of a range.
2246 	     * When no index given: "lp->ll_empty2" is TRUE.
2247 	     * Otherwise "lp->ll_n2" is set to the second index.
2248 	     */
2249 	    if (lp->ll_range && !lp->ll_empty2)
2250 	    {
2251 		lp->ll_n2 = (long)tv_get_number(&var2);
2252 						    /* is number or string */
2253 		clear_tv(&var2);
2254 		if (lp->ll_n2 < 0)
2255 		{
2256 		    ni = list_find(lp->ll_list, lp->ll_n2);
2257 		    if (ni == NULL)
2258 		    {
2259 			if (!quiet)
2260 			    semsg(_(e_listidx), lp->ll_n2);
2261 			return NULL;
2262 		    }
2263 		    lp->ll_n2 = list_idx_of_item(lp->ll_list, ni);
2264 		}
2265 
2266 		/* Check that lp->ll_n2 isn't before lp->ll_n1. */
2267 		if (lp->ll_n1 < 0)
2268 		    lp->ll_n1 = list_idx_of_item(lp->ll_list, lp->ll_li);
2269 		if (lp->ll_n2 < lp->ll_n1)
2270 		{
2271 		    if (!quiet)
2272 			semsg(_(e_listidx), lp->ll_n2);
2273 		    return NULL;
2274 		}
2275 	    }
2276 
2277 	    lp->ll_tv = &lp->ll_li->li_tv;
2278 	}
2279     }
2280 
2281     clear_tv(&var1);
2282     return p;
2283 }
2284 
2285 /*
2286  * Clear lval "lp" that was filled by get_lval().
2287  */
2288     void
2289 clear_lval(lval_T *lp)
2290 {
2291     vim_free(lp->ll_exp_name);
2292     vim_free(lp->ll_newkey);
2293 }
2294 
2295 /*
2296  * Set a variable that was parsed by get_lval() to "rettv".
2297  * "endp" points to just after the parsed name.
2298  * "op" is NULL, "+" for "+=", "-" for "-=", "*" for "*=", "/" for "/=",
2299  * "%" for "%=", "." for ".=" or "=" for "=".
2300  */
2301     static void
2302 set_var_lval(
2303     lval_T	*lp,
2304     char_u	*endp,
2305     typval_T	*rettv,
2306     int		copy,
2307     char_u	*op)
2308 {
2309     int		cc;
2310     listitem_T	*ri;
2311     dictitem_T	*di;
2312 
2313     if (lp->ll_tv == NULL)
2314     {
2315 	cc = *endp;
2316 	*endp = NUL;
2317 	if (lp->ll_blob != NULL)
2318 	{
2319 	    int	    error = FALSE, val;
2320 
2321 	    if (op != NULL && *op != '=')
2322 	    {
2323 		semsg(_(e_letwrong), op);
2324 		return;
2325 	    }
2326 
2327 	    if (lp->ll_range && rettv->v_type == VAR_BLOB)
2328 	    {
2329 		int	il, ir;
2330 
2331 		if (lp->ll_empty2)
2332 		    lp->ll_n2 = blob_len(lp->ll_blob) - 1;
2333 
2334 		if (lp->ll_n2 - lp->ll_n1 + 1 != blob_len(rettv->vval.v_blob))
2335 		{
2336 		    emsg(_("E972: Blob value does not have the right number of bytes"));
2337 		    return;
2338 		}
2339 		if (lp->ll_empty2)
2340 		    lp->ll_n2 = blob_len(lp->ll_blob);
2341 
2342 		ir = 0;
2343 		for (il = lp->ll_n1; il <= lp->ll_n2; il++)
2344 		    blob_set(lp->ll_blob, il,
2345 			    blob_get(rettv->vval.v_blob, ir++));
2346 	    }
2347 	    else
2348 	    {
2349 		val = (int)tv_get_number_chk(rettv, &error);
2350 		if (!error)
2351 		{
2352 		    garray_T *gap = &lp->ll_blob->bv_ga;
2353 
2354 		    // Allow for appending a byte.  Setting a byte beyond
2355 		    // the end is an error otherwise.
2356 		    if (lp->ll_n1 < gap->ga_len
2357 			    || (lp->ll_n1 == gap->ga_len
2358 				&& ga_grow(&lp->ll_blob->bv_ga, 1) == OK))
2359 		    {
2360 			blob_set(lp->ll_blob, lp->ll_n1, val);
2361 			if (lp->ll_n1 == gap->ga_len)
2362 			    ++gap->ga_len;
2363 		    }
2364 		    // error for invalid range was already given in get_lval()
2365 		}
2366 	    }
2367 	}
2368 	else if (op != NULL && *op != '=')
2369 	{
2370 	    typval_T tv;
2371 
2372 	    // handle +=, -=, *=, /=, %= and .=
2373 	    di = NULL;
2374 	    if (get_var_tv(lp->ll_name, (int)STRLEN(lp->ll_name),
2375 					     &tv, &di, TRUE, FALSE) == OK)
2376 	    {
2377 		if ((di == NULL
2378 			 || (!var_check_ro(di->di_flags, lp->ll_name, FALSE)
2379 			   && !tv_check_lock(&di->di_tv, lp->ll_name, FALSE)))
2380 			&& tv_op(&tv, rettv, op) == OK)
2381 		    set_var(lp->ll_name, &tv, FALSE);
2382 		clear_tv(&tv);
2383 	    }
2384 	}
2385 	else
2386 	    set_var(lp->ll_name, rettv, copy);
2387 	*endp = cc;
2388     }
2389     else if (var_check_lock(lp->ll_newkey == NULL
2390 		? lp->ll_tv->v_lock
2391 		: lp->ll_tv->vval.v_dict->dv_lock, lp->ll_name, FALSE))
2392 	;
2393     else if (lp->ll_range)
2394     {
2395 	listitem_T *ll_li = lp->ll_li;
2396 	int	    ll_n1 = lp->ll_n1;
2397 
2398 	/*
2399 	 * Check whether any of the list items is locked
2400 	 */
2401 	for (ri = rettv->vval.v_list->lv_first; ri != NULL && ll_li != NULL; )
2402 	{
2403 	    if (var_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
2404 		return;
2405 	    ri = ri->li_next;
2406 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == ll_n1))
2407 		break;
2408 	    ll_li = ll_li->li_next;
2409 	    ++ll_n1;
2410 	}
2411 
2412 	/*
2413 	 * Assign the List values to the list items.
2414 	 */
2415 	for (ri = rettv->vval.v_list->lv_first; ri != NULL; )
2416 	{
2417 	    if (op != NULL && *op != '=')
2418 		tv_op(&lp->ll_li->li_tv, &ri->li_tv, op);
2419 	    else
2420 	    {
2421 		clear_tv(&lp->ll_li->li_tv);
2422 		copy_tv(&ri->li_tv, &lp->ll_li->li_tv);
2423 	    }
2424 	    ri = ri->li_next;
2425 	    if (ri == NULL || (!lp->ll_empty2 && lp->ll_n2 == lp->ll_n1))
2426 		break;
2427 	    if (lp->ll_li->li_next == NULL)
2428 	    {
2429 		/* Need to add an empty item. */
2430 		if (list_append_number(lp->ll_list, 0) == FAIL)
2431 		{
2432 		    ri = NULL;
2433 		    break;
2434 		}
2435 	    }
2436 	    lp->ll_li = lp->ll_li->li_next;
2437 	    ++lp->ll_n1;
2438 	}
2439 	if (ri != NULL)
2440 	    emsg(_("E710: List value has more items than target"));
2441 	else if (lp->ll_empty2
2442 		? (lp->ll_li != NULL && lp->ll_li->li_next != NULL)
2443 		: lp->ll_n1 != lp->ll_n2)
2444 	    emsg(_("E711: List value has not enough items"));
2445     }
2446     else
2447     {
2448 	/*
2449 	 * Assign to a List or Dictionary item.
2450 	 */
2451 	if (lp->ll_newkey != NULL)
2452 	{
2453 	    if (op != NULL && *op != '=')
2454 	    {
2455 		semsg(_(e_letwrong), op);
2456 		return;
2457 	    }
2458 
2459 	    /* Need to add an item to the Dictionary. */
2460 	    di = dictitem_alloc(lp->ll_newkey);
2461 	    if (di == NULL)
2462 		return;
2463 	    if (dict_add(lp->ll_tv->vval.v_dict, di) == FAIL)
2464 	    {
2465 		vim_free(di);
2466 		return;
2467 	    }
2468 	    lp->ll_tv = &di->di_tv;
2469 	}
2470 	else if (op != NULL && *op != '=')
2471 	{
2472 	    tv_op(lp->ll_tv, rettv, op);
2473 	    return;
2474 	}
2475 	else
2476 	    clear_tv(lp->ll_tv);
2477 
2478 	/*
2479 	 * Assign the value to the variable or list item.
2480 	 */
2481 	if (copy)
2482 	    copy_tv(rettv, lp->ll_tv);
2483 	else
2484 	{
2485 	    *lp->ll_tv = *rettv;
2486 	    lp->ll_tv->v_lock = 0;
2487 	    init_tv(rettv);
2488 	}
2489     }
2490 }
2491 
2492 /*
2493  * Handle "tv1 += tv2", "tv1 -= tv2", "tv1 *= tv2", "tv1 /= tv2", "tv1 %= tv2"
2494  * and "tv1 .= tv2"
2495  * Returns OK or FAIL.
2496  */
2497     static int
2498 tv_op(typval_T *tv1, typval_T *tv2, char_u *op)
2499 {
2500     varnumber_T	n;
2501     char_u	numbuf[NUMBUFLEN];
2502     char_u	*s;
2503 
2504     /* Can't do anything with a Funcref, Dict, v:true on the right. */
2505     if (tv2->v_type != VAR_FUNC && tv2->v_type != VAR_DICT
2506 						&& tv2->v_type != VAR_SPECIAL)
2507     {
2508 	switch (tv1->v_type)
2509 	{
2510 	    case VAR_UNKNOWN:
2511 	    case VAR_DICT:
2512 	    case VAR_FUNC:
2513 	    case VAR_PARTIAL:
2514 	    case VAR_SPECIAL:
2515 	    case VAR_JOB:
2516 	    case VAR_CHANNEL:
2517 		break;
2518 
2519 	    case VAR_BLOB:
2520 		if (*op != '+' || tv2->v_type != VAR_BLOB)
2521 		    break;
2522 		// BLOB += BLOB
2523 		if (tv1->vval.v_blob != NULL && tv2->vval.v_blob != NULL)
2524 		{
2525 		    blob_T  *b1 = tv1->vval.v_blob;
2526 		    blob_T  *b2 = tv2->vval.v_blob;
2527 		    int	i, len = blob_len(b2);
2528 		    for (i = 0; i < len; i++)
2529 			ga_append(&b1->bv_ga, blob_get(b2, i));
2530 		}
2531 		return OK;
2532 
2533 	    case VAR_LIST:
2534 		if (*op != '+' || tv2->v_type != VAR_LIST)
2535 		    break;
2536 		// List += List
2537 		if (tv1->vval.v_list != NULL && tv2->vval.v_list != NULL)
2538 		    list_extend(tv1->vval.v_list, tv2->vval.v_list, NULL);
2539 		return OK;
2540 
2541 	    case VAR_NUMBER:
2542 	    case VAR_STRING:
2543 		if (tv2->v_type == VAR_LIST)
2544 		    break;
2545 		if (vim_strchr((char_u *)"+-*/%", *op) != NULL)
2546 		{
2547 		    // nr += nr , nr -= nr , nr *=nr , nr /= nr , nr %= nr
2548 		    n = tv_get_number(tv1);
2549 #ifdef FEAT_FLOAT
2550 		    if (tv2->v_type == VAR_FLOAT)
2551 		    {
2552 			float_T f = n;
2553 
2554 			if (*op == '%')
2555 			    break;
2556 			switch (*op)
2557 			{
2558 			    case '+': f += tv2->vval.v_float; break;
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 			}
2563 			clear_tv(tv1);
2564 			tv1->v_type = VAR_FLOAT;
2565 			tv1->vval.v_float = f;
2566 		    }
2567 		    else
2568 #endif
2569 		    {
2570 			switch (*op)
2571 			{
2572 			    case '+': n += tv_get_number(tv2); break;
2573 			    case '-': n -= tv_get_number(tv2); break;
2574 			    case '*': n *= tv_get_number(tv2); break;
2575 			    case '/': n = num_divide(n, tv_get_number(tv2)); break;
2576 			    case '%': n = num_modulus(n, tv_get_number(tv2)); break;
2577 			}
2578 			clear_tv(tv1);
2579 			tv1->v_type = VAR_NUMBER;
2580 			tv1->vval.v_number = n;
2581 		    }
2582 		}
2583 		else
2584 		{
2585 		    if (tv2->v_type == VAR_FLOAT)
2586 			break;
2587 
2588 		    // str .= str
2589 		    s = tv_get_string(tv1);
2590 		    s = concat_str(s, tv_get_string_buf(tv2, numbuf));
2591 		    clear_tv(tv1);
2592 		    tv1->v_type = VAR_STRING;
2593 		    tv1->vval.v_string = s;
2594 		}
2595 		return OK;
2596 
2597 	    case VAR_FLOAT:
2598 #ifdef FEAT_FLOAT
2599 		{
2600 		    float_T f;
2601 
2602 		    if (*op == '%' || *op == '.'
2603 				   || (tv2->v_type != VAR_FLOAT
2604 				    && tv2->v_type != VAR_NUMBER
2605 				    && tv2->v_type != VAR_STRING))
2606 			break;
2607 		    if (tv2->v_type == VAR_FLOAT)
2608 			f = tv2->vval.v_float;
2609 		    else
2610 			f = tv_get_number(tv2);
2611 		    switch (*op)
2612 		    {
2613 			case '+': tv1->vval.v_float += f; break;
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 		    }
2618 		}
2619 #endif
2620 		return OK;
2621 	}
2622     }
2623 
2624     semsg(_(e_letwrong), op);
2625     return FAIL;
2626 }
2627 
2628 /*
2629  * Evaluate the expression used in a ":for var in expr" command.
2630  * "arg" points to "var".
2631  * Set "*errp" to TRUE for an error, FALSE otherwise;
2632  * Return a pointer that holds the info.  Null when there is an error.
2633  */
2634     void *
2635 eval_for_line(
2636     char_u	*arg,
2637     int		*errp,
2638     char_u	**nextcmdp,
2639     int		skip)
2640 {
2641     forinfo_T	*fi;
2642     char_u	*expr;
2643     typval_T	tv;
2644     list_T	*l;
2645 
2646     *errp = TRUE;	/* default: there is an error */
2647 
2648     fi = (forinfo_T *)alloc_clear(sizeof(forinfo_T));
2649     if (fi == NULL)
2650 	return NULL;
2651 
2652     expr = skip_var_list(arg, &fi->fi_varcount, &fi->fi_semicolon);
2653     if (expr == NULL)
2654 	return fi;
2655 
2656     expr = skipwhite(expr);
2657     if (expr[0] != 'i' || expr[1] != 'n' || !VIM_ISWHITE(expr[2]))
2658     {
2659 	emsg(_("E690: Missing \"in\" after :for"));
2660 	return fi;
2661     }
2662 
2663     if (skip)
2664 	++emsg_skip;
2665     if (eval0(skipwhite(expr + 2), &tv, nextcmdp, !skip) == OK)
2666     {
2667 	*errp = FALSE;
2668 	if (!skip)
2669 	{
2670 	    if (tv.v_type == VAR_LIST)
2671 	    {
2672 		l = tv.vval.v_list;
2673 		if (l == NULL)
2674 		{
2675 		    // a null list is like an empty list: do nothing
2676 		    clear_tv(&tv);
2677 		}
2678 		else
2679 		{
2680 		    // No need to increment the refcount, it's already set for
2681 		    // the list being used in "tv".
2682 		    fi->fi_list = l;
2683 		    list_add_watch(l, &fi->fi_lw);
2684 		    fi->fi_lw.lw_item = l->lv_first;
2685 		}
2686 	    }
2687 	    else if (tv.v_type == VAR_BLOB)
2688 	    {
2689 		fi->fi_bi = 0;
2690 		if (tv.vval.v_blob != NULL)
2691 		{
2692 		    typval_T btv;
2693 
2694 		    // Make a copy, so that the iteration still works when the
2695 		    // blob is changed.
2696 		    blob_copy(&tv, &btv);
2697 		    fi->fi_blob = btv.vval.v_blob;
2698 		}
2699 		clear_tv(&tv);
2700 	    }
2701 	    else
2702 	    {
2703 		emsg(_(e_listreq));
2704 		clear_tv(&tv);
2705 	    }
2706 	}
2707     }
2708     if (skip)
2709 	--emsg_skip;
2710 
2711     return fi;
2712 }
2713 
2714 /*
2715  * Use the first item in a ":for" list.  Advance to the next.
2716  * Assign the values to the variable (list).  "arg" points to the first one.
2717  * Return TRUE when a valid item was found, FALSE when at end of list or
2718  * something wrong.
2719  */
2720     int
2721 next_for_item(void *fi_void, char_u *arg)
2722 {
2723     forinfo_T	*fi = (forinfo_T *)fi_void;
2724     int		result;
2725     listitem_T	*item;
2726 
2727     if (fi->fi_blob != NULL)
2728     {
2729 	typval_T	tv;
2730 
2731 	if (fi->fi_bi >= blob_len(fi->fi_blob))
2732 	    return FALSE;
2733 	tv.v_type = VAR_NUMBER;
2734 	tv.v_lock = VAR_FIXED;
2735 	tv.vval.v_number = blob_get(fi->fi_blob, fi->fi_bi);
2736 	++fi->fi_bi;
2737 	return ex_let_vars(arg, &tv, TRUE,
2738 			      fi->fi_semicolon, fi->fi_varcount, NULL) == OK;
2739     }
2740 
2741     item = fi->fi_lw.lw_item;
2742     if (item == NULL)
2743 	result = FALSE;
2744     else
2745     {
2746 	fi->fi_lw.lw_item = item->li_next;
2747 	result = (ex_let_vars(arg, &item->li_tv, TRUE,
2748 			      fi->fi_semicolon, fi->fi_varcount, NULL) == OK);
2749     }
2750     return result;
2751 }
2752 
2753 /*
2754  * Free the structure used to store info used by ":for".
2755  */
2756     void
2757 free_for_info(void *fi_void)
2758 {
2759     forinfo_T    *fi = (forinfo_T *)fi_void;
2760 
2761     if (fi != NULL && fi->fi_list != NULL)
2762     {
2763 	list_rem_watch(fi->fi_list, &fi->fi_lw);
2764 	list_unref(fi->fi_list);
2765     }
2766     if (fi != NULL && fi->fi_blob != NULL)
2767 	blob_unref(fi->fi_blob);
2768     vim_free(fi);
2769 }
2770 
2771 #if defined(FEAT_CMDL_COMPL) || defined(PROTO)
2772 
2773     void
2774 set_context_for_expression(
2775     expand_T	*xp,
2776     char_u	*arg,
2777     cmdidx_T	cmdidx)
2778 {
2779     int		got_eq = FALSE;
2780     int		c;
2781     char_u	*p;
2782 
2783     if (cmdidx == CMD_let)
2784     {
2785 	xp->xp_context = EXPAND_USER_VARS;
2786 	if (vim_strpbrk(arg, (char_u *)"\"'+-*/%.=!?~|&$([<>,#") == NULL)
2787 	{
2788 	    /* ":let var1 var2 ...": find last space. */
2789 	    for (p = arg + STRLEN(arg); p >= arg; )
2790 	    {
2791 		xp->xp_pattern = p;
2792 		MB_PTR_BACK(arg, p);
2793 		if (VIM_ISWHITE(*p))
2794 		    break;
2795 	    }
2796 	    return;
2797 	}
2798     }
2799     else
2800 	xp->xp_context = cmdidx == CMD_call ? EXPAND_FUNCTIONS
2801 							  : EXPAND_EXPRESSION;
2802     while ((xp->xp_pattern = vim_strpbrk(arg,
2803 				  (char_u *)"\"'+-*/%.=!?~|&$([<>,#")) != NULL)
2804     {
2805 	c = *xp->xp_pattern;
2806 	if (c == '&')
2807 	{
2808 	    c = xp->xp_pattern[1];
2809 	    if (c == '&')
2810 	    {
2811 		++xp->xp_pattern;
2812 		xp->xp_context = cmdidx != CMD_let || got_eq
2813 					 ? EXPAND_EXPRESSION : EXPAND_NOTHING;
2814 	    }
2815 	    else if (c != ' ')
2816 	    {
2817 		xp->xp_context = EXPAND_SETTINGS;
2818 		if ((c == 'l' || c == 'g') && xp->xp_pattern[2] == ':')
2819 		    xp->xp_pattern += 2;
2820 
2821 	    }
2822 	}
2823 	else if (c == '$')
2824 	{
2825 	    /* environment variable */
2826 	    xp->xp_context = EXPAND_ENV_VARS;
2827 	}
2828 	else if (c == '=')
2829 	{
2830 	    got_eq = TRUE;
2831 	    xp->xp_context = EXPAND_EXPRESSION;
2832 	}
2833 	else if (c == '#'
2834 		&& xp->xp_context == EXPAND_EXPRESSION)
2835 	{
2836 	    /* Autoload function/variable contains '#'. */
2837 	    break;
2838 	}
2839 	else if ((c == '<' || c == '#')
2840 		&& xp->xp_context == EXPAND_FUNCTIONS
2841 		&& vim_strchr(xp->xp_pattern, '(') == NULL)
2842 	{
2843 	    /* Function name can start with "<SNR>" and contain '#'. */
2844 	    break;
2845 	}
2846 	else if (cmdidx != CMD_let || got_eq)
2847 	{
2848 	    if (c == '"')	    /* string */
2849 	    {
2850 		while ((c = *++xp->xp_pattern) != NUL && c != '"')
2851 		    if (c == '\\' && xp->xp_pattern[1] != NUL)
2852 			++xp->xp_pattern;
2853 		xp->xp_context = EXPAND_NOTHING;
2854 	    }
2855 	    else if (c == '\'')	    /* literal string */
2856 	    {
2857 		/* Trick: '' is like stopping and starting a literal string. */
2858 		while ((c = *++xp->xp_pattern) != NUL && c != '\'')
2859 		    /* skip */ ;
2860 		xp->xp_context = EXPAND_NOTHING;
2861 	    }
2862 	    else if (c == '|')
2863 	    {
2864 		if (xp->xp_pattern[1] == '|')
2865 		{
2866 		    ++xp->xp_pattern;
2867 		    xp->xp_context = EXPAND_EXPRESSION;
2868 		}
2869 		else
2870 		    xp->xp_context = EXPAND_COMMANDS;
2871 	    }
2872 	    else
2873 		xp->xp_context = EXPAND_EXPRESSION;
2874 	}
2875 	else
2876 	    /* Doesn't look like something valid, expand as an expression
2877 	     * anyway. */
2878 	    xp->xp_context = EXPAND_EXPRESSION;
2879 	arg = xp->xp_pattern;
2880 	if (*arg != NUL)
2881 	    while ((c = *++arg) != NUL && (c == ' ' || c == '\t'))
2882 		/* skip */ ;
2883     }
2884     xp->xp_pattern = arg;
2885 }
2886 
2887 #endif /* FEAT_CMDL_COMPL */
2888 
2889 /*
2890  * ":unlet[!] var1 ... " command.
2891  */
2892     void
2893 ex_unlet(exarg_T *eap)
2894 {
2895     ex_unletlock(eap, eap->arg, 0);
2896 }
2897 
2898 /*
2899  * ":lockvar" and ":unlockvar" commands
2900  */
2901     void
2902 ex_lockvar(exarg_T *eap)
2903 {
2904     char_u	*arg = eap->arg;
2905     int		deep = 2;
2906 
2907     if (eap->forceit)
2908 	deep = -1;
2909     else if (vim_isdigit(*arg))
2910     {
2911 	deep = getdigits(&arg);
2912 	arg = skipwhite(arg);
2913     }
2914 
2915     ex_unletlock(eap, arg, deep);
2916 }
2917 
2918 /*
2919  * ":unlet", ":lockvar" and ":unlockvar" are quite similar.
2920  */
2921     static void
2922 ex_unletlock(
2923     exarg_T	*eap,
2924     char_u	*argstart,
2925     int		deep)
2926 {
2927     char_u	*arg = argstart;
2928     char_u	*name_end;
2929     int		error = FALSE;
2930     lval_T	lv;
2931 
2932     do
2933     {
2934 	if (*arg == '$')
2935 	{
2936 	    char_u    *name = ++arg;
2937 
2938 	    if (get_env_len(&arg) == 0)
2939 	    {
2940 		semsg(_(e_invarg2), name - 1);
2941 		return;
2942 	    }
2943 	    vim_unsetenv(name);
2944 	    arg = skipwhite(arg);
2945 	    continue;
2946 	}
2947 
2948 	/* Parse the name and find the end. */
2949 	name_end = get_lval(arg, NULL, &lv, TRUE, eap->skip || error, 0,
2950 							     FNE_CHECK_START);
2951 	if (lv.ll_name == NULL)
2952 	    error = TRUE;	    /* error but continue parsing */
2953 	if (name_end == NULL || (!VIM_ISWHITE(*name_end)
2954 						   && !ends_excmd(*name_end)))
2955 	{
2956 	    if (name_end != NULL)
2957 	    {
2958 		emsg_severe = TRUE;
2959 		emsg(_(e_trailing));
2960 	    }
2961 	    if (!(eap->skip || error))
2962 		clear_lval(&lv);
2963 	    break;
2964 	}
2965 
2966 	if (!error && !eap->skip)
2967 	{
2968 	    if (eap->cmdidx == CMD_unlet)
2969 	    {
2970 		if (do_unlet_var(&lv, name_end, eap->forceit) == FAIL)
2971 		    error = TRUE;
2972 	    }
2973 	    else
2974 	    {
2975 		if (do_lock_var(&lv, name_end, deep,
2976 					  eap->cmdidx == CMD_lockvar) == FAIL)
2977 		    error = TRUE;
2978 	    }
2979 	}
2980 
2981 	if (!eap->skip)
2982 	    clear_lval(&lv);
2983 
2984 	arg = skipwhite(name_end);
2985     } while (!ends_excmd(*arg));
2986 
2987     eap->nextcmd = check_nextcmd(arg);
2988 }
2989 
2990     static int
2991 do_unlet_var(
2992     lval_T	*lp,
2993     char_u	*name_end,
2994     int		forceit)
2995 {
2996     int		ret = OK;
2997     int		cc;
2998 
2999     if (lp->ll_tv == NULL)
3000     {
3001 	cc = *name_end;
3002 	*name_end = NUL;
3003 
3004 	/* Normal name or expanded name. */
3005 	if (do_unlet(lp->ll_name, forceit) == FAIL)
3006 	    ret = FAIL;
3007 	*name_end = cc;
3008     }
3009     else if ((lp->ll_list != NULL
3010 		 && var_check_lock(lp->ll_list->lv_lock, lp->ll_name, FALSE))
3011 	    || (lp->ll_dict != NULL
3012 		 && var_check_lock(lp->ll_dict->dv_lock, lp->ll_name, FALSE)))
3013 	return FAIL;
3014     else if (lp->ll_range)
3015     {
3016 	listitem_T    *li;
3017 	listitem_T    *ll_li = lp->ll_li;
3018 	int	      ll_n1 = lp->ll_n1;
3019 
3020 	while (ll_li != NULL && (lp->ll_empty2 || lp->ll_n2 >= ll_n1))
3021 	{
3022 	    li = ll_li->li_next;
3023 	    if (var_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
3024 		return FAIL;
3025 	    ll_li = li;
3026 	    ++ll_n1;
3027 	}
3028 
3029 	/* Delete a range of List items. */
3030 	while (lp->ll_li != NULL && (lp->ll_empty2 || lp->ll_n2 >= lp->ll_n1))
3031 	{
3032 	    li = lp->ll_li->li_next;
3033 	    listitem_remove(lp->ll_list, lp->ll_li);
3034 	    lp->ll_li = li;
3035 	    ++lp->ll_n1;
3036 	}
3037     }
3038     else
3039     {
3040 	if (lp->ll_list != NULL)
3041 	    /* unlet a List item. */
3042 	    listitem_remove(lp->ll_list, lp->ll_li);
3043 	else
3044 	    /* unlet a Dictionary item. */
3045 	    dictitem_remove(lp->ll_dict, lp->ll_di);
3046     }
3047 
3048     return ret;
3049 }
3050 
3051 /*
3052  * "unlet" a variable.  Return OK if it existed, FAIL if not.
3053  * When "forceit" is TRUE don't complain if the variable doesn't exist.
3054  */
3055     int
3056 do_unlet(char_u *name, int forceit)
3057 {
3058     hashtab_T	*ht;
3059     hashitem_T	*hi;
3060     char_u	*varname;
3061     dict_T	*d;
3062     dictitem_T	*di;
3063 
3064     ht = find_var_ht(name, &varname);
3065     if (ht != NULL && *varname != NUL)
3066     {
3067 	d = get_current_funccal_dict(ht);
3068 	if (d == NULL)
3069 	{
3070 	    if (ht == &globvarht)
3071 		d = &globvardict;
3072 	    else if (ht == &compat_hashtab)
3073 		d = &vimvardict;
3074 	    else
3075 	    {
3076 		di = find_var_in_ht(ht, *name, (char_u *)"", FALSE);
3077 		d = di == NULL ? NULL : di->di_tv.vval.v_dict;
3078 	    }
3079 	    if (d == NULL)
3080 	    {
3081 		internal_error("do_unlet()");
3082 		return FAIL;
3083 	    }
3084 	}
3085 	hi = hash_find(ht, varname);
3086 	if (HASHITEM_EMPTY(hi))
3087 	    hi = find_hi_in_scoped_ht(name, &ht);
3088 	if (hi != NULL && !HASHITEM_EMPTY(hi))
3089 	{
3090 	    di = HI2DI(hi);
3091 	    if (var_check_fixed(di->di_flags, name, FALSE)
3092 		    || var_check_ro(di->di_flags, name, FALSE)
3093 		    || var_check_lock(d->dv_lock, name, FALSE))
3094 		return FAIL;
3095 
3096 	    delete_var(ht, hi);
3097 	    return OK;
3098 	}
3099     }
3100     if (forceit)
3101 	return OK;
3102     semsg(_("E108: No such variable: \"%s\""), name);
3103     return FAIL;
3104 }
3105 
3106 /*
3107  * Lock or unlock variable indicated by "lp".
3108  * "deep" is the levels to go (-1 for unlimited);
3109  * "lock" is TRUE for ":lockvar", FALSE for ":unlockvar".
3110  */
3111     static int
3112 do_lock_var(
3113     lval_T	*lp,
3114     char_u	*name_end,
3115     int		deep,
3116     int		lock)
3117 {
3118     int		ret = OK;
3119     int		cc;
3120     dictitem_T	*di;
3121 
3122     if (deep == 0)	/* nothing to do */
3123 	return OK;
3124 
3125     if (lp->ll_tv == NULL)
3126     {
3127 	cc = *name_end;
3128 	*name_end = NUL;
3129 
3130 	/* Normal name or expanded name. */
3131 	di = find_var(lp->ll_name, NULL, TRUE);
3132 	if (di == NULL)
3133 	    ret = FAIL;
3134 	else if ((di->di_flags & DI_FLAGS_FIX)
3135 			&& di->di_tv.v_type != VAR_DICT
3136 			&& di->di_tv.v_type != VAR_LIST)
3137 	    /* For historic reasons this error is not given for a list or dict.
3138 	     * E.g., the b: dict could be locked/unlocked. */
3139 	    semsg(_("E940: Cannot lock or unlock variable %s"), lp->ll_name);
3140 	else
3141 	{
3142 	    if (lock)
3143 		di->di_flags |= DI_FLAGS_LOCK;
3144 	    else
3145 		di->di_flags &= ~DI_FLAGS_LOCK;
3146 	    item_lock(&di->di_tv, deep, lock);
3147 	}
3148 	*name_end = cc;
3149     }
3150     else if (lp->ll_range)
3151     {
3152 	listitem_T    *li = lp->ll_li;
3153 
3154 	/* (un)lock a range of List items. */
3155 	while (li != NULL && (lp->ll_empty2 || lp->ll_n2 >= lp->ll_n1))
3156 	{
3157 	    item_lock(&li->li_tv, deep, lock);
3158 	    li = li->li_next;
3159 	    ++lp->ll_n1;
3160 	}
3161     }
3162     else if (lp->ll_list != NULL)
3163 	/* (un)lock a List item. */
3164 	item_lock(&lp->ll_li->li_tv, deep, lock);
3165     else
3166 	/* (un)lock a Dictionary item. */
3167 	item_lock(&lp->ll_di->di_tv, deep, lock);
3168 
3169     return ret;
3170 }
3171 
3172 /*
3173  * Lock or unlock an item.  "deep" is nr of levels to go.
3174  */
3175     static void
3176 item_lock(typval_T *tv, int deep, int lock)
3177 {
3178     static int	recurse = 0;
3179     list_T	*l;
3180     listitem_T	*li;
3181     dict_T	*d;
3182     blob_T	*b;
3183     hashitem_T	*hi;
3184     int		todo;
3185 
3186     if (recurse >= DICT_MAXNEST)
3187     {
3188 	emsg(_("E743: variable nested too deep for (un)lock"));
3189 	return;
3190     }
3191     if (deep == 0)
3192 	return;
3193     ++recurse;
3194 
3195     /* lock/unlock the item itself */
3196     if (lock)
3197 	tv->v_lock |= VAR_LOCKED;
3198     else
3199 	tv->v_lock &= ~VAR_LOCKED;
3200 
3201     switch (tv->v_type)
3202     {
3203 	case VAR_UNKNOWN:
3204 	case VAR_NUMBER:
3205 	case VAR_STRING:
3206 	case VAR_FUNC:
3207 	case VAR_PARTIAL:
3208 	case VAR_FLOAT:
3209 	case VAR_SPECIAL:
3210 	case VAR_JOB:
3211 	case VAR_CHANNEL:
3212 	    break;
3213 
3214 	case VAR_BLOB:
3215 	    if ((b = tv->vval.v_blob) != NULL)
3216 	    {
3217 		if (lock)
3218 		    b->bv_lock |= VAR_LOCKED;
3219 		else
3220 		    b->bv_lock &= ~VAR_LOCKED;
3221 	    }
3222 	    break;
3223 	case VAR_LIST:
3224 	    if ((l = tv->vval.v_list) != NULL)
3225 	    {
3226 		if (lock)
3227 		    l->lv_lock |= VAR_LOCKED;
3228 		else
3229 		    l->lv_lock &= ~VAR_LOCKED;
3230 		if (deep < 0 || deep > 1)
3231 		    /* recursive: lock/unlock the items the List contains */
3232 		    for (li = l->lv_first; li != NULL; li = li->li_next)
3233 			item_lock(&li->li_tv, deep - 1, lock);
3234 	    }
3235 	    break;
3236 	case VAR_DICT:
3237 	    if ((d = tv->vval.v_dict) != NULL)
3238 	    {
3239 		if (lock)
3240 		    d->dv_lock |= VAR_LOCKED;
3241 		else
3242 		    d->dv_lock &= ~VAR_LOCKED;
3243 		if (deep < 0 || deep > 1)
3244 		{
3245 		    /* recursive: lock/unlock the items the List contains */
3246 		    todo = (int)d->dv_hashtab.ht_used;
3247 		    for (hi = d->dv_hashtab.ht_array; todo > 0; ++hi)
3248 		    {
3249 			if (!HASHITEM_EMPTY(hi))
3250 			{
3251 			    --todo;
3252 			    item_lock(&HI2DI(hi)->di_tv, deep - 1, lock);
3253 			}
3254 		    }
3255 		}
3256 	    }
3257     }
3258     --recurse;
3259 }
3260 
3261 #if (defined(FEAT_MENU) && defined(FEAT_MULTI_LANG)) || defined(PROTO)
3262 /*
3263  * Delete all "menutrans_" variables.
3264  */
3265     void
3266 del_menutrans_vars(void)
3267 {
3268     hashitem_T	*hi;
3269     int		todo;
3270 
3271     hash_lock(&globvarht);
3272     todo = (int)globvarht.ht_used;
3273     for (hi = globvarht.ht_array; todo > 0 && !got_int; ++hi)
3274     {
3275 	if (!HASHITEM_EMPTY(hi))
3276 	{
3277 	    --todo;
3278 	    if (STRNCMP(HI2DI(hi)->di_key, "menutrans_", 10) == 0)
3279 		delete_var(&globvarht, hi);
3280 	}
3281     }
3282     hash_unlock(&globvarht);
3283 }
3284 #endif
3285 
3286 #if defined(FEAT_CMDL_COMPL) || defined(PROTO)
3287 
3288 /*
3289  * Local string buffer for the next two functions to store a variable name
3290  * with its prefix. Allocated in cat_prefix_varname(), freed later in
3291  * get_user_var_name().
3292  */
3293 
3294 static char_u	*varnamebuf = NULL;
3295 static int	varnamebuflen = 0;
3296 
3297 /*
3298  * Function to concatenate a prefix and a variable name.
3299  */
3300     static char_u *
3301 cat_prefix_varname(int prefix, char_u *name)
3302 {
3303     int		len;
3304 
3305     len = (int)STRLEN(name) + 3;
3306     if (len > varnamebuflen)
3307     {
3308 	vim_free(varnamebuf);
3309 	len += 10;			/* some additional space */
3310 	varnamebuf = alloc(len);
3311 	if (varnamebuf == NULL)
3312 	{
3313 	    varnamebuflen = 0;
3314 	    return NULL;
3315 	}
3316 	varnamebuflen = len;
3317     }
3318     *varnamebuf = prefix;
3319     varnamebuf[1] = ':';
3320     STRCPY(varnamebuf + 2, name);
3321     return varnamebuf;
3322 }
3323 
3324 /*
3325  * Function given to ExpandGeneric() to obtain the list of user defined
3326  * (global/buffer/window/built-in) variable names.
3327  */
3328     char_u *
3329 get_user_var_name(expand_T *xp, int idx)
3330 {
3331     static long_u	gdone;
3332     static long_u	bdone;
3333     static long_u	wdone;
3334     static long_u	tdone;
3335     static int		vidx;
3336     static hashitem_T	*hi;
3337     hashtab_T		*ht;
3338 
3339     if (idx == 0)
3340     {
3341 	gdone = bdone = wdone = vidx = 0;
3342 	tdone = 0;
3343     }
3344 
3345     /* Global variables */
3346     if (gdone < globvarht.ht_used)
3347     {
3348 	if (gdone++ == 0)
3349 	    hi = globvarht.ht_array;
3350 	else
3351 	    ++hi;
3352 	while (HASHITEM_EMPTY(hi))
3353 	    ++hi;
3354 	if (STRNCMP("g:", xp->xp_pattern, 2) == 0)
3355 	    return cat_prefix_varname('g', hi->hi_key);
3356 	return hi->hi_key;
3357     }
3358 
3359     /* b: variables */
3360     ht = &curbuf->b_vars->dv_hashtab;
3361     if (bdone < ht->ht_used)
3362     {
3363 	if (bdone++ == 0)
3364 	    hi = ht->ht_array;
3365 	else
3366 	    ++hi;
3367 	while (HASHITEM_EMPTY(hi))
3368 	    ++hi;
3369 	return cat_prefix_varname('b', hi->hi_key);
3370     }
3371 
3372     /* w: variables */
3373     ht = &curwin->w_vars->dv_hashtab;
3374     if (wdone < ht->ht_used)
3375     {
3376 	if (wdone++ == 0)
3377 	    hi = ht->ht_array;
3378 	else
3379 	    ++hi;
3380 	while (HASHITEM_EMPTY(hi))
3381 	    ++hi;
3382 	return cat_prefix_varname('w', hi->hi_key);
3383     }
3384 
3385     /* t: variables */
3386     ht = &curtab->tp_vars->dv_hashtab;
3387     if (tdone < ht->ht_used)
3388     {
3389 	if (tdone++ == 0)
3390 	    hi = ht->ht_array;
3391 	else
3392 	    ++hi;
3393 	while (HASHITEM_EMPTY(hi))
3394 	    ++hi;
3395 	return cat_prefix_varname('t', hi->hi_key);
3396     }
3397 
3398     /* v: variables */
3399     if (vidx < VV_LEN)
3400 	return cat_prefix_varname('v', (char_u *)vimvars[vidx++].vv_name);
3401 
3402     VIM_CLEAR(varnamebuf);
3403     varnamebuflen = 0;
3404     return NULL;
3405 }
3406 
3407 #endif /* FEAT_CMDL_COMPL */
3408 
3409 /*
3410  * Return TRUE if "pat" matches "text".
3411  * Does not use 'cpo' and always uses 'magic'.
3412  */
3413     static int
3414 pattern_match(char_u *pat, char_u *text, int ic)
3415 {
3416     int		matches = FALSE;
3417     char_u	*save_cpo;
3418     regmatch_T	regmatch;
3419 
3420     /* avoid 'l' flag in 'cpoptions' */
3421     save_cpo = p_cpo;
3422     p_cpo = (char_u *)"";
3423     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
3424     if (regmatch.regprog != NULL)
3425     {
3426 	regmatch.rm_ic = ic;
3427 	matches = vim_regexec_nl(&regmatch, text, (colnr_T)0);
3428 	vim_regfree(regmatch.regprog);
3429     }
3430     p_cpo = save_cpo;
3431     return matches;
3432 }
3433 
3434 /*
3435  * The "evaluate" argument: When FALSE, the argument is only parsed but not
3436  * executed.  The function may return OK, but the rettv will be of type
3437  * VAR_UNKNOWN.  The function still returns FAIL for a syntax error.
3438  */
3439 
3440 /*
3441  * Handle zero level expression.
3442  * This calls eval1() and handles error message and nextcmd.
3443  * Put the result in "rettv" when returning OK and "evaluate" is TRUE.
3444  * Note: "rettv.v_lock" is not set.
3445  * Return OK or FAIL.
3446  */
3447     int
3448 eval0(
3449     char_u	*arg,
3450     typval_T	*rettv,
3451     char_u	**nextcmd,
3452     int		evaluate)
3453 {
3454     int		ret;
3455     char_u	*p;
3456     int		did_emsg_before = did_emsg;
3457     int		called_emsg_before = called_emsg;
3458 
3459     p = skipwhite(arg);
3460     ret = eval1(&p, rettv, evaluate);
3461     if (ret == FAIL || !ends_excmd(*p))
3462     {
3463 	if (ret != FAIL)
3464 	    clear_tv(rettv);
3465 	/*
3466 	 * Report the invalid expression unless the expression evaluation has
3467 	 * been cancelled due to an aborting error, an interrupt, or an
3468 	 * exception, or we already gave a more specific error.
3469 	 * Also check called_emsg for when using assert_fails().
3470 	 */
3471 	if (!aborting() && did_emsg == did_emsg_before
3472 					  && called_emsg == called_emsg_before)
3473 	    semsg(_(e_invexpr2), arg);
3474 	ret = FAIL;
3475     }
3476     if (nextcmd != NULL)
3477 	*nextcmd = check_nextcmd(p);
3478 
3479     return ret;
3480 }
3481 
3482 /*
3483  * Handle top level expression:
3484  *	expr2 ? expr1 : expr1
3485  *
3486  * "arg" must point to the first non-white of the expression.
3487  * "arg" is advanced to the next non-white after the recognized expression.
3488  *
3489  * Note: "rettv.v_lock" is not set.
3490  *
3491  * Return OK or FAIL.
3492  */
3493     int
3494 eval1(char_u **arg, typval_T *rettv, int evaluate)
3495 {
3496     int		result;
3497     typval_T	var2;
3498 
3499     /*
3500      * Get the first variable.
3501      */
3502     if (eval2(arg, rettv, evaluate) == FAIL)
3503 	return FAIL;
3504 
3505     if ((*arg)[0] == '?')
3506     {
3507 	result = FALSE;
3508 	if (evaluate)
3509 	{
3510 	    int		error = FALSE;
3511 
3512 	    if (tv_get_number_chk(rettv, &error) != 0)
3513 		result = TRUE;
3514 	    clear_tv(rettv);
3515 	    if (error)
3516 		return FAIL;
3517 	}
3518 
3519 	/*
3520 	 * Get the second variable.
3521 	 */
3522 	*arg = skipwhite(*arg + 1);
3523 	if (eval1(arg, rettv, evaluate && result) == FAIL) /* recursive! */
3524 	    return FAIL;
3525 
3526 	/*
3527 	 * Check for the ":".
3528 	 */
3529 	if ((*arg)[0] != ':')
3530 	{
3531 	    emsg(_("E109: Missing ':' after '?'"));
3532 	    if (evaluate && result)
3533 		clear_tv(rettv);
3534 	    return FAIL;
3535 	}
3536 
3537 	/*
3538 	 * Get the third variable.
3539 	 */
3540 	*arg = skipwhite(*arg + 1);
3541 	if (eval1(arg, &var2, evaluate && !result) == FAIL) /* recursive! */
3542 	{
3543 	    if (evaluate && result)
3544 		clear_tv(rettv);
3545 	    return FAIL;
3546 	}
3547 	if (evaluate && !result)
3548 	    *rettv = var2;
3549     }
3550 
3551     return OK;
3552 }
3553 
3554 /*
3555  * Handle first level expression:
3556  *	expr2 || expr2 || expr2	    logical OR
3557  *
3558  * "arg" must point to the first non-white of the expression.
3559  * "arg" is advanced to the next non-white after the recognized expression.
3560  *
3561  * Return OK or FAIL.
3562  */
3563     static int
3564 eval2(char_u **arg, typval_T *rettv, int evaluate)
3565 {
3566     typval_T	var2;
3567     long	result;
3568     int		first;
3569     int		error = FALSE;
3570 
3571     /*
3572      * Get the first variable.
3573      */
3574     if (eval3(arg, rettv, evaluate) == FAIL)
3575 	return FAIL;
3576 
3577     /*
3578      * Repeat until there is no following "||".
3579      */
3580     first = TRUE;
3581     result = FALSE;
3582     while ((*arg)[0] == '|' && (*arg)[1] == '|')
3583     {
3584 	if (evaluate && first)
3585 	{
3586 	    if (tv_get_number_chk(rettv, &error) != 0)
3587 		result = TRUE;
3588 	    clear_tv(rettv);
3589 	    if (error)
3590 		return FAIL;
3591 	    first = FALSE;
3592 	}
3593 
3594 	/*
3595 	 * Get the second variable.
3596 	 */
3597 	*arg = skipwhite(*arg + 2);
3598 	if (eval3(arg, &var2, evaluate && !result) == FAIL)
3599 	    return FAIL;
3600 
3601 	/*
3602 	 * Compute the result.
3603 	 */
3604 	if (evaluate && !result)
3605 	{
3606 	    if (tv_get_number_chk(&var2, &error) != 0)
3607 		result = TRUE;
3608 	    clear_tv(&var2);
3609 	    if (error)
3610 		return FAIL;
3611 	}
3612 	if (evaluate)
3613 	{
3614 	    rettv->v_type = VAR_NUMBER;
3615 	    rettv->vval.v_number = result;
3616 	}
3617     }
3618 
3619     return OK;
3620 }
3621 
3622 /*
3623  * Handle second level expression:
3624  *	expr3 && expr3 && expr3	    logical AND
3625  *
3626  * "arg" must point to the first non-white of the expression.
3627  * "arg" is advanced to the next non-white after the recognized expression.
3628  *
3629  * Return OK or FAIL.
3630  */
3631     static int
3632 eval3(char_u **arg, typval_T *rettv, int evaluate)
3633 {
3634     typval_T	var2;
3635     long	result;
3636     int		first;
3637     int		error = FALSE;
3638 
3639     /*
3640      * Get the first variable.
3641      */
3642     if (eval4(arg, rettv, evaluate) == FAIL)
3643 	return FAIL;
3644 
3645     /*
3646      * Repeat until there is no following "&&".
3647      */
3648     first = TRUE;
3649     result = TRUE;
3650     while ((*arg)[0] == '&' && (*arg)[1] == '&')
3651     {
3652 	if (evaluate && first)
3653 	{
3654 	    if (tv_get_number_chk(rettv, &error) == 0)
3655 		result = FALSE;
3656 	    clear_tv(rettv);
3657 	    if (error)
3658 		return FAIL;
3659 	    first = FALSE;
3660 	}
3661 
3662 	/*
3663 	 * Get the second variable.
3664 	 */
3665 	*arg = skipwhite(*arg + 2);
3666 	if (eval4(arg, &var2, evaluate && result) == FAIL)
3667 	    return FAIL;
3668 
3669 	/*
3670 	 * Compute the result.
3671 	 */
3672 	if (evaluate && result)
3673 	{
3674 	    if (tv_get_number_chk(&var2, &error) == 0)
3675 		result = FALSE;
3676 	    clear_tv(&var2);
3677 	    if (error)
3678 		return FAIL;
3679 	}
3680 	if (evaluate)
3681 	{
3682 	    rettv->v_type = VAR_NUMBER;
3683 	    rettv->vval.v_number = result;
3684 	}
3685     }
3686 
3687     return OK;
3688 }
3689 
3690 /*
3691  * Handle third level expression:
3692  *	var1 == var2
3693  *	var1 =~ var2
3694  *	var1 != var2
3695  *	var1 !~ var2
3696  *	var1 > var2
3697  *	var1 >= var2
3698  *	var1 < var2
3699  *	var1 <= var2
3700  *	var1 is var2
3701  *	var1 isnot var2
3702  *
3703  * "arg" must point to the first non-white of the expression.
3704  * "arg" is advanced to the next non-white after the recognized expression.
3705  *
3706  * Return OK or FAIL.
3707  */
3708     static int
3709 eval4(char_u **arg, typval_T *rettv, int evaluate)
3710 {
3711     typval_T	var2;
3712     char_u	*p;
3713     int		i;
3714     exptype_T	type = TYPE_UNKNOWN;
3715     int		type_is = FALSE;    /* TRUE for "is" and "isnot" */
3716     int		len = 2;
3717     int		ic;
3718 
3719     /*
3720      * Get the first variable.
3721      */
3722     if (eval5(arg, rettv, evaluate) == FAIL)
3723 	return FAIL;
3724 
3725     p = *arg;
3726     switch (p[0])
3727     {
3728 	case '=':   if (p[1] == '=')
3729 			type = TYPE_EQUAL;
3730 		    else if (p[1] == '~')
3731 			type = TYPE_MATCH;
3732 		    break;
3733 	case '!':   if (p[1] == '=')
3734 			type = TYPE_NEQUAL;
3735 		    else if (p[1] == '~')
3736 			type = TYPE_NOMATCH;
3737 		    break;
3738 	case '>':   if (p[1] != '=')
3739 		    {
3740 			type = TYPE_GREATER;
3741 			len = 1;
3742 		    }
3743 		    else
3744 			type = TYPE_GEQUAL;
3745 		    break;
3746 	case '<':   if (p[1] != '=')
3747 		    {
3748 			type = TYPE_SMALLER;
3749 			len = 1;
3750 		    }
3751 		    else
3752 			type = TYPE_SEQUAL;
3753 		    break;
3754 	case 'i':   if (p[1] == 's')
3755 		    {
3756 			if (p[2] == 'n' && p[3] == 'o' && p[4] == 't')
3757 			    len = 5;
3758 			i = p[len];
3759 			if (!isalnum(i) && i != '_')
3760 			{
3761 			    type = len == 2 ? TYPE_EQUAL : TYPE_NEQUAL;
3762 			    type_is = TRUE;
3763 			}
3764 		    }
3765 		    break;
3766     }
3767 
3768     /*
3769      * If there is a comparative operator, use it.
3770      */
3771     if (type != TYPE_UNKNOWN)
3772     {
3773 	/* extra question mark appended: ignore case */
3774 	if (p[len] == '?')
3775 	{
3776 	    ic = TRUE;
3777 	    ++len;
3778 	}
3779 	/* extra '#' appended: match case */
3780 	else if (p[len] == '#')
3781 	{
3782 	    ic = FALSE;
3783 	    ++len;
3784 	}
3785 	/* nothing appended: use 'ignorecase' */
3786 	else
3787 	    ic = p_ic;
3788 
3789 	/*
3790 	 * Get the second variable.
3791 	 */
3792 	*arg = skipwhite(p + len);
3793 	if (eval5(arg, &var2, evaluate) == FAIL)
3794 	{
3795 	    clear_tv(rettv);
3796 	    return FAIL;
3797 	}
3798 	if (evaluate)
3799 	{
3800 	    int ret = typval_compare(rettv, &var2, type, type_is, ic);
3801 
3802 	    clear_tv(&var2);
3803 	    return ret;
3804 	}
3805     }
3806 
3807     return OK;
3808 }
3809 
3810 /*
3811  * Handle fourth level expression:
3812  *	+	number addition
3813  *	-	number subtraction
3814  *	.	string concatenation
3815  *
3816  * "arg" must point to the first non-white of the expression.
3817  * "arg" is advanced to the next non-white after the recognized expression.
3818  *
3819  * Return OK or FAIL.
3820  */
3821     static int
3822 eval5(char_u **arg, typval_T *rettv, int evaluate)
3823 {
3824     typval_T	var2;
3825     typval_T	var3;
3826     int		op;
3827     varnumber_T	n1, n2;
3828 #ifdef FEAT_FLOAT
3829     float_T	f1 = 0, f2 = 0;
3830 #endif
3831     char_u	*s1, *s2;
3832     char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
3833     char_u	*p;
3834 
3835     /*
3836      * Get the first variable.
3837      */
3838     if (eval6(arg, rettv, evaluate, FALSE) == FAIL)
3839 	return FAIL;
3840 
3841     /*
3842      * Repeat computing, until no '+', '-' or '.' is following.
3843      */
3844     for (;;)
3845     {
3846 	op = **arg;
3847 	if (op != '+' && op != '-' && op != '.')
3848 	    break;
3849 
3850 	if ((op != '+' || (rettv->v_type != VAR_LIST
3851 						 && rettv->v_type != VAR_BLOB))
3852 #ifdef FEAT_FLOAT
3853 		&& (op == '.' || rettv->v_type != VAR_FLOAT)
3854 #endif
3855 		)
3856 	{
3857 	    /* For "list + ...", an illegal use of the first operand as
3858 	     * a number cannot be determined before evaluating the 2nd
3859 	     * operand: if this is also a list, all is ok.
3860 	     * For "something . ...", "something - ..." or "non-list + ...",
3861 	     * we know that the first operand needs to be a string or number
3862 	     * without evaluating the 2nd operand.  So check before to avoid
3863 	     * side effects after an error. */
3864 	    if (evaluate && tv_get_string_chk(rettv) == NULL)
3865 	    {
3866 		clear_tv(rettv);
3867 		return FAIL;
3868 	    }
3869 	}
3870 
3871 	/*
3872 	 * Get the second variable.
3873 	 */
3874 	*arg = skipwhite(*arg + 1);
3875 	if (eval6(arg, &var2, evaluate, op == '.') == FAIL)
3876 	{
3877 	    clear_tv(rettv);
3878 	    return FAIL;
3879 	}
3880 
3881 	if (evaluate)
3882 	{
3883 	    /*
3884 	     * Compute the result.
3885 	     */
3886 	    if (op == '.')
3887 	    {
3888 		s1 = tv_get_string_buf(rettv, buf1);	/* already checked */
3889 		s2 = tv_get_string_buf_chk(&var2, buf2);
3890 		if (s2 == NULL)		/* type error ? */
3891 		{
3892 		    clear_tv(rettv);
3893 		    clear_tv(&var2);
3894 		    return FAIL;
3895 		}
3896 		p = concat_str(s1, s2);
3897 		clear_tv(rettv);
3898 		rettv->v_type = VAR_STRING;
3899 		rettv->vval.v_string = p;
3900 	    }
3901 	    else if (op == '+' && rettv->v_type == VAR_BLOB
3902 						   && var2.v_type == VAR_BLOB)
3903 	    {
3904 		blob_T  *b1 = rettv->vval.v_blob;
3905 		blob_T  *b2 = var2.vval.v_blob;
3906 		blob_T	*b = blob_alloc();
3907 		int	i;
3908 
3909 		if (b != NULL)
3910 		{
3911 		    for (i = 0; i < blob_len(b1); i++)
3912 			ga_append(&b->bv_ga, blob_get(b1, i));
3913 		    for (i = 0; i < blob_len(b2); i++)
3914 			ga_append(&b->bv_ga, blob_get(b2, i));
3915 
3916 		    clear_tv(rettv);
3917 		    rettv_blob_set(rettv, b);
3918 		}
3919 	    }
3920 	    else if (op == '+' && rettv->v_type == VAR_LIST
3921 						   && var2.v_type == VAR_LIST)
3922 	    {
3923 		/* concatenate Lists */
3924 		if (list_concat(rettv->vval.v_list, var2.vval.v_list,
3925 							       &var3) == FAIL)
3926 		{
3927 		    clear_tv(rettv);
3928 		    clear_tv(&var2);
3929 		    return FAIL;
3930 		}
3931 		clear_tv(rettv);
3932 		*rettv = var3;
3933 	    }
3934 	    else
3935 	    {
3936 		int	    error = FALSE;
3937 
3938 #ifdef FEAT_FLOAT
3939 		if (rettv->v_type == VAR_FLOAT)
3940 		{
3941 		    f1 = rettv->vval.v_float;
3942 		    n1 = 0;
3943 		}
3944 		else
3945 #endif
3946 		{
3947 		    n1 = tv_get_number_chk(rettv, &error);
3948 		    if (error)
3949 		    {
3950 			/* This can only happen for "list + non-list".  For
3951 			 * "non-list + ..." or "something - ...", we returned
3952 			 * before evaluating the 2nd operand. */
3953 			clear_tv(rettv);
3954 			return FAIL;
3955 		    }
3956 #ifdef FEAT_FLOAT
3957 		    if (var2.v_type == VAR_FLOAT)
3958 			f1 = n1;
3959 #endif
3960 		}
3961 #ifdef FEAT_FLOAT
3962 		if (var2.v_type == VAR_FLOAT)
3963 		{
3964 		    f2 = var2.vval.v_float;
3965 		    n2 = 0;
3966 		}
3967 		else
3968 #endif
3969 		{
3970 		    n2 = tv_get_number_chk(&var2, &error);
3971 		    if (error)
3972 		    {
3973 			clear_tv(rettv);
3974 			clear_tv(&var2);
3975 			return FAIL;
3976 		    }
3977 #ifdef FEAT_FLOAT
3978 		    if (rettv->v_type == VAR_FLOAT)
3979 			f2 = n2;
3980 #endif
3981 		}
3982 		clear_tv(rettv);
3983 
3984 #ifdef FEAT_FLOAT
3985 		/* If there is a float on either side the result is a float. */
3986 		if (rettv->v_type == VAR_FLOAT || var2.v_type == VAR_FLOAT)
3987 		{
3988 		    if (op == '+')
3989 			f1 = f1 + f2;
3990 		    else
3991 			f1 = f1 - f2;
3992 		    rettv->v_type = VAR_FLOAT;
3993 		    rettv->vval.v_float = f1;
3994 		}
3995 		else
3996 #endif
3997 		{
3998 		    if (op == '+')
3999 			n1 = n1 + n2;
4000 		    else
4001 			n1 = n1 - n2;
4002 		    rettv->v_type = VAR_NUMBER;
4003 		    rettv->vval.v_number = n1;
4004 		}
4005 	    }
4006 	    clear_tv(&var2);
4007 	}
4008     }
4009     return OK;
4010 }
4011 
4012 /*
4013  * Handle fifth level expression:
4014  *	*	number multiplication
4015  *	/	number division
4016  *	%	number modulo
4017  *
4018  * "arg" must point to the first non-white of the expression.
4019  * "arg" is advanced to the next non-white after the recognized expression.
4020  *
4021  * Return OK or FAIL.
4022  */
4023     static int
4024 eval6(
4025     char_u	**arg,
4026     typval_T	*rettv,
4027     int		evaluate,
4028     int		want_string)  /* after "." operator */
4029 {
4030     typval_T	var2;
4031     int		op;
4032     varnumber_T	n1, n2;
4033 #ifdef FEAT_FLOAT
4034     int		use_float = FALSE;
4035     float_T	f1 = 0, f2;
4036 #endif
4037     int		error = FALSE;
4038 
4039     /*
4040      * Get the first variable.
4041      */
4042     if (eval7(arg, rettv, evaluate, want_string) == FAIL)
4043 	return FAIL;
4044 
4045     /*
4046      * Repeat computing, until no '*', '/' or '%' is following.
4047      */
4048     for (;;)
4049     {
4050 	op = **arg;
4051 	if (op != '*' && op != '/' && op != '%')
4052 	    break;
4053 
4054 	if (evaluate)
4055 	{
4056 #ifdef FEAT_FLOAT
4057 	    if (rettv->v_type == VAR_FLOAT)
4058 	    {
4059 		f1 = rettv->vval.v_float;
4060 		use_float = TRUE;
4061 		n1 = 0;
4062 	    }
4063 	    else
4064 #endif
4065 		n1 = tv_get_number_chk(rettv, &error);
4066 	    clear_tv(rettv);
4067 	    if (error)
4068 		return FAIL;
4069 	}
4070 	else
4071 	    n1 = 0;
4072 
4073 	/*
4074 	 * Get the second variable.
4075 	 */
4076 	*arg = skipwhite(*arg + 1);
4077 	if (eval7(arg, &var2, evaluate, FALSE) == FAIL)
4078 	    return FAIL;
4079 
4080 	if (evaluate)
4081 	{
4082 #ifdef FEAT_FLOAT
4083 	    if (var2.v_type == VAR_FLOAT)
4084 	    {
4085 		if (!use_float)
4086 		{
4087 		    f1 = n1;
4088 		    use_float = TRUE;
4089 		}
4090 		f2 = var2.vval.v_float;
4091 		n2 = 0;
4092 	    }
4093 	    else
4094 #endif
4095 	    {
4096 		n2 = tv_get_number_chk(&var2, &error);
4097 		clear_tv(&var2);
4098 		if (error)
4099 		    return FAIL;
4100 #ifdef FEAT_FLOAT
4101 		if (use_float)
4102 		    f2 = n2;
4103 #endif
4104 	    }
4105 
4106 	    /*
4107 	     * Compute the result.
4108 	     * When either side is a float the result is a float.
4109 	     */
4110 #ifdef FEAT_FLOAT
4111 	    if (use_float)
4112 	    {
4113 		if (op == '*')
4114 		    f1 = f1 * f2;
4115 		else if (op == '/')
4116 		{
4117 # ifdef VMS
4118 		    /* VMS crashes on divide by zero, work around it */
4119 		    if (f2 == 0.0)
4120 		    {
4121 			if (f1 == 0)
4122 			    f1 = -1 * __F_FLT_MAX - 1L;   /* similar to NaN */
4123 			else if (f1 < 0)
4124 			    f1 = -1 * __F_FLT_MAX;
4125 			else
4126 			    f1 = __F_FLT_MAX;
4127 		    }
4128 		    else
4129 			f1 = f1 / f2;
4130 # else
4131 		    /* We rely on the floating point library to handle divide
4132 		     * by zero to result in "inf" and not a crash. */
4133 		    f1 = f1 / f2;
4134 # endif
4135 		}
4136 		else
4137 		{
4138 		    emsg(_("E804: Cannot use '%' with Float"));
4139 		    return FAIL;
4140 		}
4141 		rettv->v_type = VAR_FLOAT;
4142 		rettv->vval.v_float = f1;
4143 	    }
4144 	    else
4145 #endif
4146 	    {
4147 		if (op == '*')
4148 		    n1 = n1 * n2;
4149 		else if (op == '/')
4150 		    n1 = num_divide(n1, n2);
4151 		else
4152 		    n1 = num_modulus(n1, n2);
4153 
4154 		rettv->v_type = VAR_NUMBER;
4155 		rettv->vval.v_number = n1;
4156 	    }
4157 	}
4158     }
4159 
4160     return OK;
4161 }
4162 
4163 /*
4164  * Handle sixth level expression:
4165  *  number		number constant
4166  *  0zFFFFFFFF		Blob constant
4167  *  "string"		string constant
4168  *  'string'		literal string constant
4169  *  &option-name	option value
4170  *  @r			register contents
4171  *  identifier		variable value
4172  *  function()		function call
4173  *  $VAR		environment variable
4174  *  (expression)	nested expression
4175  *  [expr, expr]	List
4176  *  {key: val, key: val}  Dictionary
4177  *
4178  *  Also handle:
4179  *  ! in front		logical NOT
4180  *  - in front		unary minus
4181  *  + in front		unary plus (ignored)
4182  *  trailing []		subscript in String or List
4183  *  trailing .name	entry in Dictionary
4184  *
4185  * "arg" must point to the first non-white of the expression.
4186  * "arg" is advanced to the next non-white after the recognized expression.
4187  *
4188  * Return OK or FAIL.
4189  */
4190     static int
4191 eval7(
4192     char_u	**arg,
4193     typval_T	*rettv,
4194     int		evaluate,
4195     int		want_string UNUSED)	/* after "." operator */
4196 {
4197     varnumber_T	n;
4198     int		len;
4199     char_u	*s;
4200     char_u	*start_leader, *end_leader;
4201     int		ret = OK;
4202     char_u	*alias;
4203 
4204     /*
4205      * Initialise variable so that clear_tv() can't mistake this for a
4206      * string and free a string that isn't there.
4207      */
4208     rettv->v_type = VAR_UNKNOWN;
4209 
4210     /*
4211      * Skip '!', '-' and '+' characters.  They are handled later.
4212      */
4213     start_leader = *arg;
4214     while (**arg == '!' || **arg == '-' || **arg == '+')
4215 	*arg = skipwhite(*arg + 1);
4216     end_leader = *arg;
4217 
4218     switch (**arg)
4219     {
4220     /*
4221      * Number constant.
4222      */
4223     case '0':
4224     case '1':
4225     case '2':
4226     case '3':
4227     case '4':
4228     case '5':
4229     case '6':
4230     case '7':
4231     case '8':
4232     case '9':
4233 	{
4234 #ifdef FEAT_FLOAT
4235 		char_u *p = skipdigits(*arg + 1);
4236 		int    get_float = FALSE;
4237 
4238 		/* We accept a float when the format matches
4239 		 * "[0-9]\+\.[0-9]\+\([eE][+-]\?[0-9]\+\)\?".  This is very
4240 		 * strict to avoid backwards compatibility problems.
4241 		 * Don't look for a float after the "." operator, so that
4242 		 * ":let vers = 1.2.3" doesn't fail. */
4243 		if (!want_string && p[0] == '.' && vim_isdigit(p[1]))
4244 		{
4245 		    get_float = TRUE;
4246 		    p = skipdigits(p + 2);
4247 		    if (*p == 'e' || *p == 'E')
4248 		    {
4249 			++p;
4250 			if (*p == '-' || *p == '+')
4251 			    ++p;
4252 			if (!vim_isdigit(*p))
4253 			    get_float = FALSE;
4254 			else
4255 			    p = skipdigits(p + 1);
4256 		    }
4257 		    if (ASCII_ISALPHA(*p) || *p == '.')
4258 			get_float = FALSE;
4259 		}
4260 		if (get_float)
4261 		{
4262 		    float_T	f;
4263 
4264 		    *arg += string2float(*arg, &f);
4265 		    if (evaluate)
4266 		    {
4267 			rettv->v_type = VAR_FLOAT;
4268 			rettv->vval.v_float = f;
4269 		    }
4270 		}
4271 		else
4272 #endif
4273 		if (**arg == '0' && ((*arg)[1] == 'z' || (*arg)[1] == 'Z'))
4274 		{
4275 		    char_u  *bp;
4276 		    blob_T  *blob = NULL;  // init for gcc
4277 
4278 		    // Blob constant: 0z0123456789abcdef
4279 		    if (evaluate)
4280 			blob = blob_alloc();
4281 		    for (bp = *arg + 2; vim_isxdigit(bp[0]); bp += 2)
4282 		    {
4283 			if (!vim_isxdigit(bp[1]))
4284 			{
4285 			    if (blob != NULL)
4286 			    {
4287 				emsg(_("E973: Blob literal should have an even number of hex characters"));
4288 				ga_clear(&blob->bv_ga);
4289 				VIM_CLEAR(blob);
4290 			    }
4291 			    ret = FAIL;
4292 			    break;
4293 			}
4294 			if (blob != NULL)
4295 			    ga_append(&blob->bv_ga,
4296 					 (hex2nr(*bp) << 4) + hex2nr(*(bp+1)));
4297 			if (bp[2] == '.' && vim_isxdigit(bp[3]))
4298 			    ++bp;
4299 		    }
4300 		    if (blob != NULL)
4301 			rettv_blob_set(rettv, blob);
4302 		    *arg = bp;
4303 		}
4304 		else
4305 		{
4306 		    // decimal, hex or octal number
4307 		    vim_str2nr(*arg, NULL, &len, STR2NR_ALL, &n, NULL, 0);
4308 		    *arg += len;
4309 		    if (evaluate)
4310 		    {
4311 			rettv->v_type = VAR_NUMBER;
4312 			rettv->vval.v_number = n;
4313 		    }
4314 		}
4315 		break;
4316 	}
4317 
4318     /*
4319      * String constant: "string".
4320      */
4321     case '"':	ret = get_string_tv(arg, rettv, evaluate);
4322 		break;
4323 
4324     /*
4325      * Literal string constant: 'str''ing'.
4326      */
4327     case '\'':	ret = get_lit_string_tv(arg, rettv, evaluate);
4328 		break;
4329 
4330     /*
4331      * List: [expr, expr]
4332      */
4333     case '[':	ret = get_list_tv(arg, rettv, evaluate);
4334 		break;
4335 
4336     /*
4337      * Lambda: {arg, arg -> expr}
4338      * Dictionary: {key: val, key: val}
4339      */
4340     case '{':	ret = get_lambda_tv(arg, rettv, evaluate);
4341 		if (ret == NOTDONE)
4342 		    ret = dict_get_tv(arg, rettv, evaluate);
4343 		break;
4344 
4345     /*
4346      * Option value: &name
4347      */
4348     case '&':	ret = get_option_tv(arg, rettv, evaluate);
4349 		break;
4350 
4351     /*
4352      * Environment variable: $VAR.
4353      */
4354     case '$':	ret = get_env_tv(arg, rettv, evaluate);
4355 		break;
4356 
4357     /*
4358      * Register contents: @r.
4359      */
4360     case '@':	++*arg;
4361 		if (evaluate)
4362 		{
4363 		    rettv->v_type = VAR_STRING;
4364 		    rettv->vval.v_string = get_reg_contents(**arg,
4365 							    GREG_EXPR_SRC);
4366 		}
4367 		if (**arg != NUL)
4368 		    ++*arg;
4369 		break;
4370 
4371     /*
4372      * nested expression: (expression).
4373      */
4374     case '(':	*arg = skipwhite(*arg + 1);
4375 		ret = eval1(arg, rettv, evaluate);	/* recursive! */
4376 		if (**arg == ')')
4377 		    ++*arg;
4378 		else if (ret == OK)
4379 		{
4380 		    emsg(_("E110: Missing ')'"));
4381 		    clear_tv(rettv);
4382 		    ret = FAIL;
4383 		}
4384 		break;
4385 
4386     default:	ret = NOTDONE;
4387 		break;
4388     }
4389 
4390     if (ret == NOTDONE)
4391     {
4392 	/*
4393 	 * Must be a variable or function name.
4394 	 * Can also be a curly-braces kind of name: {expr}.
4395 	 */
4396 	s = *arg;
4397 	len = get_name_len(arg, &alias, evaluate, TRUE);
4398 	if (alias != NULL)
4399 	    s = alias;
4400 
4401 	if (len <= 0)
4402 	    ret = FAIL;
4403 	else
4404 	{
4405 	    if (**arg == '(')		/* recursive! */
4406 	    {
4407 		partial_T *partial;
4408 
4409 		if (!evaluate)
4410 		    check_vars(s, len);
4411 
4412 		/* If "s" is the name of a variable of type VAR_FUNC
4413 		 * use its contents. */
4414 		s = deref_func_name(s, &len, &partial, !evaluate);
4415 
4416 		/* Need to make a copy, in case evaluating the arguments makes
4417 		 * the name invalid. */
4418 		s = vim_strsave(s);
4419 		if (s == NULL)
4420 		    ret = FAIL;
4421 		else
4422 		    /* Invoke the function. */
4423 		    ret = get_func_tv(s, len, rettv, arg,
4424 			      curwin->w_cursor.lnum, curwin->w_cursor.lnum,
4425 			      &len, evaluate, partial, NULL);
4426 		vim_free(s);
4427 
4428 		/* If evaluate is FALSE rettv->v_type was not set in
4429 		 * get_func_tv, but it's needed in handle_subscript() to parse
4430 		 * what follows. So set it here. */
4431 		if (rettv->v_type == VAR_UNKNOWN && !evaluate && **arg == '(')
4432 		{
4433 		    rettv->vval.v_string = NULL;
4434 		    rettv->v_type = VAR_FUNC;
4435 		}
4436 
4437 		/* Stop the expression evaluation when immediately
4438 		 * aborting on error, or when an interrupt occurred or
4439 		 * an exception was thrown but not caught. */
4440 		if (aborting())
4441 		{
4442 		    if (ret == OK)
4443 			clear_tv(rettv);
4444 		    ret = FAIL;
4445 		}
4446 	    }
4447 	    else if (evaluate)
4448 		ret = get_var_tv(s, len, rettv, NULL, TRUE, FALSE);
4449 	    else
4450 	    {
4451 		check_vars(s, len);
4452 		ret = OK;
4453 	    }
4454 	}
4455 	vim_free(alias);
4456     }
4457 
4458     *arg = skipwhite(*arg);
4459 
4460     /* Handle following '[', '(' and '.' for expr[expr], expr.name,
4461      * expr(expr). */
4462     if (ret == OK)
4463 	ret = handle_subscript(arg, rettv, evaluate, TRUE);
4464 
4465     /*
4466      * Apply logical NOT and unary '-', from right to left, ignore '+'.
4467      */
4468     if (ret == OK && evaluate && end_leader > start_leader)
4469     {
4470 	int	    error = FALSE;
4471 	varnumber_T val = 0;
4472 #ifdef FEAT_FLOAT
4473 	float_T	    f = 0.0;
4474 
4475 	if (rettv->v_type == VAR_FLOAT)
4476 	    f = rettv->vval.v_float;
4477 	else
4478 #endif
4479 	    val = tv_get_number_chk(rettv, &error);
4480 	if (error)
4481 	{
4482 	    clear_tv(rettv);
4483 	    ret = FAIL;
4484 	}
4485 	else
4486 	{
4487 	    while (end_leader > start_leader)
4488 	    {
4489 		--end_leader;
4490 		if (*end_leader == '!')
4491 		{
4492 #ifdef FEAT_FLOAT
4493 		    if (rettv->v_type == VAR_FLOAT)
4494 			f = !f;
4495 		    else
4496 #endif
4497 			val = !val;
4498 		}
4499 		else if (*end_leader == '-')
4500 		{
4501 #ifdef FEAT_FLOAT
4502 		    if (rettv->v_type == VAR_FLOAT)
4503 			f = -f;
4504 		    else
4505 #endif
4506 			val = -val;
4507 		}
4508 	    }
4509 #ifdef FEAT_FLOAT
4510 	    if (rettv->v_type == VAR_FLOAT)
4511 	    {
4512 		clear_tv(rettv);
4513 		rettv->vval.v_float = f;
4514 	    }
4515 	    else
4516 #endif
4517 	    {
4518 		clear_tv(rettv);
4519 		rettv->v_type = VAR_NUMBER;
4520 		rettv->vval.v_number = val;
4521 	    }
4522 	}
4523     }
4524 
4525     return ret;
4526 }
4527 
4528 /*
4529  * Evaluate an "[expr]" or "[expr:expr]" index.  Also "dict.key".
4530  * "*arg" points to the '[' or '.'.
4531  * Returns FAIL or OK. "*arg" is advanced to after the ']'.
4532  */
4533     static int
4534 eval_index(
4535     char_u	**arg,
4536     typval_T	*rettv,
4537     int		evaluate,
4538     int		verbose)	/* give error messages */
4539 {
4540     int		empty1 = FALSE, empty2 = FALSE;
4541     typval_T	var1, var2;
4542     long	i;
4543     long	n1, n2 = 0;
4544     long	len = -1;
4545     int		range = FALSE;
4546     char_u	*s;
4547     char_u	*key = NULL;
4548 
4549     switch (rettv->v_type)
4550     {
4551 	case VAR_FUNC:
4552 	case VAR_PARTIAL:
4553 	    if (verbose)
4554 		emsg(_("E695: Cannot index a Funcref"));
4555 	    return FAIL;
4556 	case VAR_FLOAT:
4557 #ifdef FEAT_FLOAT
4558 	    if (verbose)
4559 		emsg(_(e_float_as_string));
4560 	    return FAIL;
4561 #endif
4562 	case VAR_SPECIAL:
4563 	case VAR_JOB:
4564 	case VAR_CHANNEL:
4565 	    if (verbose)
4566 		emsg(_("E909: Cannot index a special variable"));
4567 	    return FAIL;
4568 	case VAR_UNKNOWN:
4569 	    if (evaluate)
4570 		return FAIL;
4571 	    /* FALLTHROUGH */
4572 
4573 	case VAR_STRING:
4574 	case VAR_NUMBER:
4575 	case VAR_LIST:
4576 	case VAR_DICT:
4577 	case VAR_BLOB:
4578 	    break;
4579     }
4580 
4581     init_tv(&var1);
4582     init_tv(&var2);
4583     if (**arg == '.')
4584     {
4585 	/*
4586 	 * dict.name
4587 	 */
4588 	key = *arg + 1;
4589 	for (len = 0; ASCII_ISALNUM(key[len]) || key[len] == '_'; ++len)
4590 	    ;
4591 	if (len == 0)
4592 	    return FAIL;
4593 	*arg = skipwhite(key + len);
4594     }
4595     else
4596     {
4597 	/*
4598 	 * something[idx]
4599 	 *
4600 	 * Get the (first) variable from inside the [].
4601 	 */
4602 	*arg = skipwhite(*arg + 1);
4603 	if (**arg == ':')
4604 	    empty1 = TRUE;
4605 	else if (eval1(arg, &var1, evaluate) == FAIL)	/* recursive! */
4606 	    return FAIL;
4607 	else if (evaluate && tv_get_string_chk(&var1) == NULL)
4608 	{
4609 	    /* not a number or string */
4610 	    clear_tv(&var1);
4611 	    return FAIL;
4612 	}
4613 
4614 	/*
4615 	 * Get the second variable from inside the [:].
4616 	 */
4617 	if (**arg == ':')
4618 	{
4619 	    range = TRUE;
4620 	    *arg = skipwhite(*arg + 1);
4621 	    if (**arg == ']')
4622 		empty2 = TRUE;
4623 	    else if (eval1(arg, &var2, evaluate) == FAIL)	/* recursive! */
4624 	    {
4625 		if (!empty1)
4626 		    clear_tv(&var1);
4627 		return FAIL;
4628 	    }
4629 	    else if (evaluate && tv_get_string_chk(&var2) == NULL)
4630 	    {
4631 		/* not a number or string */
4632 		if (!empty1)
4633 		    clear_tv(&var1);
4634 		clear_tv(&var2);
4635 		return FAIL;
4636 	    }
4637 	}
4638 
4639 	/* Check for the ']'. */
4640 	if (**arg != ']')
4641 	{
4642 	    if (verbose)
4643 		emsg(_(e_missbrac));
4644 	    clear_tv(&var1);
4645 	    if (range)
4646 		clear_tv(&var2);
4647 	    return FAIL;
4648 	}
4649 	*arg = skipwhite(*arg + 1);	/* skip the ']' */
4650     }
4651 
4652     if (evaluate)
4653     {
4654 	n1 = 0;
4655 	if (!empty1 && rettv->v_type != VAR_DICT)
4656 	{
4657 	    n1 = tv_get_number(&var1);
4658 	    clear_tv(&var1);
4659 	}
4660 	if (range)
4661 	{
4662 	    if (empty2)
4663 		n2 = -1;
4664 	    else
4665 	    {
4666 		n2 = tv_get_number(&var2);
4667 		clear_tv(&var2);
4668 	    }
4669 	}
4670 
4671 	switch (rettv->v_type)
4672 	{
4673 	    case VAR_UNKNOWN:
4674 	    case VAR_FUNC:
4675 	    case VAR_PARTIAL:
4676 	    case VAR_FLOAT:
4677 	    case VAR_SPECIAL:
4678 	    case VAR_JOB:
4679 	    case VAR_CHANNEL:
4680 		break; /* not evaluating, skipping over subscript */
4681 
4682 	    case VAR_NUMBER:
4683 	    case VAR_STRING:
4684 		s = tv_get_string(rettv);
4685 		len = (long)STRLEN(s);
4686 		if (range)
4687 		{
4688 		    /* The resulting variable is a substring.  If the indexes
4689 		     * are out of range the result is empty. */
4690 		    if (n1 < 0)
4691 		    {
4692 			n1 = len + n1;
4693 			if (n1 < 0)
4694 			    n1 = 0;
4695 		    }
4696 		    if (n2 < 0)
4697 			n2 = len + n2;
4698 		    else if (n2 >= len)
4699 			n2 = len;
4700 		    if (n1 >= len || n2 < 0 || n1 > n2)
4701 			s = NULL;
4702 		    else
4703 			s = vim_strnsave(s + n1, (int)(n2 - n1 + 1));
4704 		}
4705 		else
4706 		{
4707 		    /* The resulting variable is a string of a single
4708 		     * character.  If the index is too big or negative the
4709 		     * result is empty. */
4710 		    if (n1 >= len || n1 < 0)
4711 			s = NULL;
4712 		    else
4713 			s = vim_strnsave(s + n1, 1);
4714 		}
4715 		clear_tv(rettv);
4716 		rettv->v_type = VAR_STRING;
4717 		rettv->vval.v_string = s;
4718 		break;
4719 
4720 	    case VAR_BLOB:
4721 		len = blob_len(rettv->vval.v_blob);
4722 		if (range)
4723 		{
4724 		    // The resulting variable is a sub-blob.  If the indexes
4725 		    // are out of range the result is empty.
4726 		    if (n1 < 0)
4727 		    {
4728 			n1 = len + n1;
4729 			if (n1 < 0)
4730 			    n1 = 0;
4731 		    }
4732 		    if (n2 < 0)
4733 			n2 = len + n2;
4734 		    else if (n2 >= len)
4735 			n2 = len - 1;
4736 		    if (n1 >= len || n2 < 0 || n1 > n2)
4737 		    {
4738 			clear_tv(rettv);
4739 			rettv->v_type = VAR_BLOB;
4740 			rettv->vval.v_blob = NULL;
4741 		    }
4742 		    else
4743 		    {
4744 			blob_T  *blob = blob_alloc();
4745 
4746 			if (blob != NULL)
4747 			{
4748 			    if (ga_grow(&blob->bv_ga, n2 - n1 + 1) == FAIL)
4749 			    {
4750 				blob_free(blob);
4751 				return FAIL;
4752 			    }
4753 			    blob->bv_ga.ga_len = n2 - n1 + 1;
4754 			    for (i = n1; i <= n2; i++)
4755 				blob_set(blob, i - n1,
4756 					      blob_get(rettv->vval.v_blob, i));
4757 
4758 			    clear_tv(rettv);
4759 			    rettv_blob_set(rettv, blob);
4760 			}
4761 		    }
4762 		}
4763 		else
4764 		{
4765 		    // The resulting variable is a byte value.
4766 		    // If the index is too big or negative that is an error.
4767 		    if (n1 < 0)
4768 			n1 = len + n1;
4769 		    if (n1 < len && n1 >= 0)
4770 		    {
4771 			int v = blob_get(rettv->vval.v_blob, n1);
4772 
4773 			clear_tv(rettv);
4774 			rettv->v_type = VAR_NUMBER;
4775 			rettv->vval.v_number = v;
4776 		    }
4777 		    else
4778 			semsg(_(e_blobidx), n1);
4779 		}
4780 		break;
4781 
4782 	    case VAR_LIST:
4783 		len = list_len(rettv->vval.v_list);
4784 		if (n1 < 0)
4785 		    n1 = len + n1;
4786 		if (!empty1 && (n1 < 0 || n1 >= len))
4787 		{
4788 		    /* For a range we allow invalid values and return an empty
4789 		     * list.  A list index out of range is an error. */
4790 		    if (!range)
4791 		    {
4792 			if (verbose)
4793 			    semsg(_(e_listidx), n1);
4794 			return FAIL;
4795 		    }
4796 		    n1 = len;
4797 		}
4798 		if (range)
4799 		{
4800 		    list_T	*l;
4801 		    listitem_T	*item;
4802 
4803 		    if (n2 < 0)
4804 			n2 = len + n2;
4805 		    else if (n2 >= len)
4806 			n2 = len - 1;
4807 		    if (!empty2 && (n2 < 0 || n2 + 1 < n1))
4808 			n2 = -1;
4809 		    l = list_alloc();
4810 		    if (l == NULL)
4811 			return FAIL;
4812 		    for (item = list_find(rettv->vval.v_list, n1);
4813 							       n1 <= n2; ++n1)
4814 		    {
4815 			if (list_append_tv(l, &item->li_tv) == FAIL)
4816 			{
4817 			    list_free(l);
4818 			    return FAIL;
4819 			}
4820 			item = item->li_next;
4821 		    }
4822 		    clear_tv(rettv);
4823 		    rettv_list_set(rettv, l);
4824 		}
4825 		else
4826 		{
4827 		    copy_tv(&list_find(rettv->vval.v_list, n1)->li_tv, &var1);
4828 		    clear_tv(rettv);
4829 		    *rettv = var1;
4830 		}
4831 		break;
4832 
4833 	    case VAR_DICT:
4834 		if (range)
4835 		{
4836 		    if (verbose)
4837 			emsg(_(e_dictrange));
4838 		    if (len == -1)
4839 			clear_tv(&var1);
4840 		    return FAIL;
4841 		}
4842 		{
4843 		    dictitem_T	*item;
4844 
4845 		    if (len == -1)
4846 		    {
4847 			key = tv_get_string_chk(&var1);
4848 			if (key == NULL)
4849 			{
4850 			    clear_tv(&var1);
4851 			    return FAIL;
4852 			}
4853 		    }
4854 
4855 		    item = dict_find(rettv->vval.v_dict, key, (int)len);
4856 
4857 		    if (item == NULL && verbose)
4858 			semsg(_(e_dictkey), key);
4859 		    if (len == -1)
4860 			clear_tv(&var1);
4861 		    if (item == NULL)
4862 			return FAIL;
4863 
4864 		    copy_tv(&item->di_tv, &var1);
4865 		    clear_tv(rettv);
4866 		    *rettv = var1;
4867 		}
4868 		break;
4869 	}
4870     }
4871 
4872     return OK;
4873 }
4874 
4875 /*
4876  * Get an option value.
4877  * "arg" points to the '&' or '+' before the option name.
4878  * "arg" is advanced to character after the option name.
4879  * Return OK or FAIL.
4880  */
4881     int
4882 get_option_tv(
4883     char_u	**arg,
4884     typval_T	*rettv,	/* when NULL, only check if option exists */
4885     int		evaluate)
4886 {
4887     char_u	*option_end;
4888     long	numval;
4889     char_u	*stringval;
4890     int		opt_type;
4891     int		c;
4892     int		working = (**arg == '+');    /* has("+option") */
4893     int		ret = OK;
4894     int		opt_flags;
4895 
4896     /*
4897      * Isolate the option name and find its value.
4898      */
4899     option_end = find_option_end(arg, &opt_flags);
4900     if (option_end == NULL)
4901     {
4902 	if (rettv != NULL)
4903 	    semsg(_("E112: Option name missing: %s"), *arg);
4904 	return FAIL;
4905     }
4906 
4907     if (!evaluate)
4908     {
4909 	*arg = option_end;
4910 	return OK;
4911     }
4912 
4913     c = *option_end;
4914     *option_end = NUL;
4915     opt_type = get_option_value(*arg, &numval,
4916 			       rettv == NULL ? NULL : &stringval, opt_flags);
4917 
4918     if (opt_type == -3)			/* invalid name */
4919     {
4920 	if (rettv != NULL)
4921 	    semsg(_("E113: Unknown option: %s"), *arg);
4922 	ret = FAIL;
4923     }
4924     else if (rettv != NULL)
4925     {
4926 	if (opt_type == -2)		/* hidden string option */
4927 	{
4928 	    rettv->v_type = VAR_STRING;
4929 	    rettv->vval.v_string = NULL;
4930 	}
4931 	else if (opt_type == -1)	/* hidden number option */
4932 	{
4933 	    rettv->v_type = VAR_NUMBER;
4934 	    rettv->vval.v_number = 0;
4935 	}
4936 	else if (opt_type == 1)		/* number option */
4937 	{
4938 	    rettv->v_type = VAR_NUMBER;
4939 	    rettv->vval.v_number = numval;
4940 	}
4941 	else				/* string option */
4942 	{
4943 	    rettv->v_type = VAR_STRING;
4944 	    rettv->vval.v_string = stringval;
4945 	}
4946     }
4947     else if (working && (opt_type == -2 || opt_type == -1))
4948 	ret = FAIL;
4949 
4950     *option_end = c;		    /* put back for error messages */
4951     *arg = option_end;
4952 
4953     return ret;
4954 }
4955 
4956 /*
4957  * Allocate a variable for a string constant.
4958  * Return OK or FAIL.
4959  */
4960     static int
4961 get_string_tv(char_u **arg, typval_T *rettv, int evaluate)
4962 {
4963     char_u	*p;
4964     char_u	*name;
4965     int		extra = 0;
4966 
4967     /*
4968      * Find the end of the string, skipping backslashed characters.
4969      */
4970     for (p = *arg + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
4971     {
4972 	if (*p == '\\' && p[1] != NUL)
4973 	{
4974 	    ++p;
4975 	    /* A "\<x>" form occupies at least 4 characters, and produces up
4976 	     * to 6 characters: reserve space for 2 extra */
4977 	    if (*p == '<')
4978 		extra += 2;
4979 	}
4980     }
4981 
4982     if (*p != '"')
4983     {
4984 	semsg(_("E114: Missing quote: %s"), *arg);
4985 	return FAIL;
4986     }
4987 
4988     /* If only parsing, set *arg and return here */
4989     if (!evaluate)
4990     {
4991 	*arg = p + 1;
4992 	return OK;
4993     }
4994 
4995     /*
4996      * Copy the string into allocated memory, handling backslashed
4997      * characters.
4998      */
4999     name = alloc((unsigned)(p - *arg + extra));
5000     if (name == NULL)
5001 	return FAIL;
5002     rettv->v_type = VAR_STRING;
5003     rettv->vval.v_string = name;
5004 
5005     for (p = *arg + 1; *p != NUL && *p != '"'; )
5006     {
5007 	if (*p == '\\')
5008 	{
5009 	    switch (*++p)
5010 	    {
5011 		case 'b': *name++ = BS; ++p; break;
5012 		case 'e': *name++ = ESC; ++p; break;
5013 		case 'f': *name++ = FF; ++p; break;
5014 		case 'n': *name++ = NL; ++p; break;
5015 		case 'r': *name++ = CAR; ++p; break;
5016 		case 't': *name++ = TAB; ++p; break;
5017 
5018 		case 'X': /* hex: "\x1", "\x12" */
5019 		case 'x':
5020 		case 'u': /* Unicode: "\u0023" */
5021 		case 'U':
5022 			  if (vim_isxdigit(p[1]))
5023 			  {
5024 			      int	n, nr;
5025 			      int	c = toupper(*p);
5026 
5027 			      if (c == 'X')
5028 				  n = 2;
5029 			      else if (*p == 'u')
5030 				  n = 4;
5031 			      else
5032 				  n = 8;
5033 			      nr = 0;
5034 			      while (--n >= 0 && vim_isxdigit(p[1]))
5035 			      {
5036 				  ++p;
5037 				  nr = (nr << 4) + hex2nr(*p);
5038 			      }
5039 			      ++p;
5040 			      /* For "\u" store the number according to
5041 			       * 'encoding'. */
5042 			      if (c != 'X')
5043 				  name += (*mb_char2bytes)(nr, name);
5044 			      else
5045 				  *name++ = nr;
5046 			  }
5047 			  break;
5048 
5049 			  /* octal: "\1", "\12", "\123" */
5050 		case '0':
5051 		case '1':
5052 		case '2':
5053 		case '3':
5054 		case '4':
5055 		case '5':
5056 		case '6':
5057 		case '7': *name = *p++ - '0';
5058 			  if (*p >= '0' && *p <= '7')
5059 			  {
5060 			      *name = (*name << 3) + *p++ - '0';
5061 			      if (*p >= '0' && *p <= '7')
5062 				  *name = (*name << 3) + *p++ - '0';
5063 			  }
5064 			  ++name;
5065 			  break;
5066 
5067 			    /* Special key, e.g.: "\<C-W>" */
5068 		case '<': extra = trans_special(&p, name, TRUE, TRUE);
5069 			  if (extra != 0)
5070 			  {
5071 			      name += extra;
5072 			      break;
5073 			  }
5074 			  /* FALLTHROUGH */
5075 
5076 		default:  MB_COPY_CHAR(p, name);
5077 			  break;
5078 	    }
5079 	}
5080 	else
5081 	    MB_COPY_CHAR(p, name);
5082 
5083     }
5084     *name = NUL;
5085     if (*p != NUL) /* just in case */
5086 	++p;
5087     *arg = p;
5088 
5089     return OK;
5090 }
5091 
5092 /*
5093  * Allocate a variable for a 'str''ing' constant.
5094  * Return OK or FAIL.
5095  */
5096     static int
5097 get_lit_string_tv(char_u **arg, typval_T *rettv, int evaluate)
5098 {
5099     char_u	*p;
5100     char_u	*str;
5101     int		reduce = 0;
5102 
5103     /*
5104      * Find the end of the string, skipping ''.
5105      */
5106     for (p = *arg + 1; *p != NUL; MB_PTR_ADV(p))
5107     {
5108 	if (*p == '\'')
5109 	{
5110 	    if (p[1] != '\'')
5111 		break;
5112 	    ++reduce;
5113 	    ++p;
5114 	}
5115     }
5116 
5117     if (*p != '\'')
5118     {
5119 	semsg(_("E115: Missing quote: %s"), *arg);
5120 	return FAIL;
5121     }
5122 
5123     /* If only parsing return after setting "*arg" */
5124     if (!evaluate)
5125     {
5126 	*arg = p + 1;
5127 	return OK;
5128     }
5129 
5130     /*
5131      * Copy the string into allocated memory, handling '' to ' reduction.
5132      */
5133     str = alloc((unsigned)((p - *arg) - reduce));
5134     if (str == NULL)
5135 	return FAIL;
5136     rettv->v_type = VAR_STRING;
5137     rettv->vval.v_string = str;
5138 
5139     for (p = *arg + 1; *p != NUL; )
5140     {
5141 	if (*p == '\'')
5142 	{
5143 	    if (p[1] != '\'')
5144 		break;
5145 	    ++p;
5146 	}
5147 	MB_COPY_CHAR(p, str);
5148     }
5149     *str = NUL;
5150     *arg = p + 1;
5151 
5152     return OK;
5153 }
5154 
5155 /*
5156  * Return the function name of the partial.
5157  */
5158     char_u *
5159 partial_name(partial_T *pt)
5160 {
5161     if (pt->pt_name != NULL)
5162 	return pt->pt_name;
5163     return pt->pt_func->uf_name;
5164 }
5165 
5166     static void
5167 partial_free(partial_T *pt)
5168 {
5169     int i;
5170 
5171     for (i = 0; i < pt->pt_argc; ++i)
5172 	clear_tv(&pt->pt_argv[i]);
5173     vim_free(pt->pt_argv);
5174     dict_unref(pt->pt_dict);
5175     if (pt->pt_name != NULL)
5176     {
5177 	func_unref(pt->pt_name);
5178 	vim_free(pt->pt_name);
5179     }
5180     else
5181 	func_ptr_unref(pt->pt_func);
5182     vim_free(pt);
5183 }
5184 
5185 /*
5186  * Unreference a closure: decrement the reference count and free it when it
5187  * becomes zero.
5188  */
5189     void
5190 partial_unref(partial_T *pt)
5191 {
5192     if (pt != NULL && --pt->pt_refcount <= 0)
5193 	partial_free(pt);
5194 }
5195 
5196 static int tv_equal_recurse_limit;
5197 
5198     static int
5199 func_equal(
5200     typval_T *tv1,
5201     typval_T *tv2,
5202     int	     ic)	    /* ignore case */
5203 {
5204     char_u	*s1, *s2;
5205     dict_T	*d1, *d2;
5206     int		a1, a2;
5207     int		i;
5208 
5209     /* empty and NULL function name considered the same */
5210     s1 = tv1->v_type == VAR_FUNC ? tv1->vval.v_string
5211 					   : partial_name(tv1->vval.v_partial);
5212     if (s1 != NULL && *s1 == NUL)
5213 	s1 = NULL;
5214     s2 = tv2->v_type == VAR_FUNC ? tv2->vval.v_string
5215 					   : partial_name(tv2->vval.v_partial);
5216     if (s2 != NULL && *s2 == NUL)
5217 	s2 = NULL;
5218     if (s1 == NULL || s2 == NULL)
5219     {
5220 	if (s1 != s2)
5221 	    return FALSE;
5222     }
5223     else if (STRCMP(s1, s2) != 0)
5224 	return FALSE;
5225 
5226     /* empty dict and NULL dict is different */
5227     d1 = tv1->v_type == VAR_FUNC ? NULL : tv1->vval.v_partial->pt_dict;
5228     d2 = tv2->v_type == VAR_FUNC ? NULL : tv2->vval.v_partial->pt_dict;
5229     if (d1 == NULL || d2 == NULL)
5230     {
5231 	if (d1 != d2)
5232 	    return FALSE;
5233     }
5234     else if (!dict_equal(d1, d2, ic, TRUE))
5235 	return FALSE;
5236 
5237     /* empty list and no list considered the same */
5238     a1 = tv1->v_type == VAR_FUNC ? 0 : tv1->vval.v_partial->pt_argc;
5239     a2 = tv2->v_type == VAR_FUNC ? 0 : tv2->vval.v_partial->pt_argc;
5240     if (a1 != a2)
5241 	return FALSE;
5242     for (i = 0; i < a1; ++i)
5243 	if (!tv_equal(tv1->vval.v_partial->pt_argv + i,
5244 		      tv2->vval.v_partial->pt_argv + i, ic, TRUE))
5245 	    return FALSE;
5246 
5247     return TRUE;
5248 }
5249 
5250 /*
5251  * Return TRUE if "tv1" and "tv2" have the same value.
5252  * Compares the items just like "==" would compare them, but strings and
5253  * numbers are different.  Floats and numbers are also different.
5254  */
5255     int
5256 tv_equal(
5257     typval_T *tv1,
5258     typval_T *tv2,
5259     int	     ic,	    /* ignore case */
5260     int	     recursive)	    /* TRUE when used recursively */
5261 {
5262     char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
5263     char_u	*s1, *s2;
5264     static int  recursive_cnt = 0;	    /* catch recursive loops */
5265     int		r;
5266 
5267     /* Catch lists and dicts that have an endless loop by limiting
5268      * recursiveness to a limit.  We guess they are equal then.
5269      * A fixed limit has the problem of still taking an awful long time.
5270      * Reduce the limit every time running into it. That should work fine for
5271      * deeply linked structures that are not recursively linked and catch
5272      * recursiveness quickly. */
5273     if (!recursive)
5274 	tv_equal_recurse_limit = 1000;
5275     if (recursive_cnt >= tv_equal_recurse_limit)
5276     {
5277 	--tv_equal_recurse_limit;
5278 	return TRUE;
5279     }
5280 
5281     /* For VAR_FUNC and VAR_PARTIAL compare the function name, bound dict and
5282      * arguments. */
5283     if ((tv1->v_type == VAR_FUNC
5284 		|| (tv1->v_type == VAR_PARTIAL && tv1->vval.v_partial != NULL))
5285 	    && (tv2->v_type == VAR_FUNC
5286 		|| (tv2->v_type == VAR_PARTIAL && tv2->vval.v_partial != NULL)))
5287     {
5288 	++recursive_cnt;
5289 	r = func_equal(tv1, tv2, ic);
5290 	--recursive_cnt;
5291 	return r;
5292     }
5293 
5294     if (tv1->v_type != tv2->v_type)
5295 	return FALSE;
5296 
5297     switch (tv1->v_type)
5298     {
5299 	case VAR_LIST:
5300 	    ++recursive_cnt;
5301 	    r = list_equal(tv1->vval.v_list, tv2->vval.v_list, ic, TRUE);
5302 	    --recursive_cnt;
5303 	    return r;
5304 
5305 	case VAR_DICT:
5306 	    ++recursive_cnt;
5307 	    r = dict_equal(tv1->vval.v_dict, tv2->vval.v_dict, ic, TRUE);
5308 	    --recursive_cnt;
5309 	    return r;
5310 
5311 	case VAR_BLOB:
5312 	    return blob_equal(tv1->vval.v_blob, tv2->vval.v_blob);
5313 
5314 	case VAR_NUMBER:
5315 	    return tv1->vval.v_number == tv2->vval.v_number;
5316 
5317 	case VAR_STRING:
5318 	    s1 = tv_get_string_buf(tv1, buf1);
5319 	    s2 = tv_get_string_buf(tv2, buf2);
5320 	    return ((ic ? MB_STRICMP(s1, s2) : STRCMP(s1, s2)) == 0);
5321 
5322 	case VAR_SPECIAL:
5323 	    return tv1->vval.v_number == tv2->vval.v_number;
5324 
5325 	case VAR_FLOAT:
5326 #ifdef FEAT_FLOAT
5327 	    return tv1->vval.v_float == tv2->vval.v_float;
5328 #endif
5329 	case VAR_JOB:
5330 #ifdef FEAT_JOB_CHANNEL
5331 	    return tv1->vval.v_job == tv2->vval.v_job;
5332 #endif
5333 	case VAR_CHANNEL:
5334 #ifdef FEAT_JOB_CHANNEL
5335 	    return tv1->vval.v_channel == tv2->vval.v_channel;
5336 #endif
5337 	case VAR_FUNC:
5338 	case VAR_PARTIAL:
5339 	case VAR_UNKNOWN:
5340 	    break;
5341     }
5342 
5343     /* VAR_UNKNOWN can be the result of a invalid expression, let's say it
5344      * does not equal anything, not even itself. */
5345     return FALSE;
5346 }
5347 
5348 /*
5349  * Return the next (unique) copy ID.
5350  * Used for serializing nested structures.
5351  */
5352     int
5353 get_copyID(void)
5354 {
5355     current_copyID += COPYID_INC;
5356     return current_copyID;
5357 }
5358 
5359 /*
5360  * Garbage collection for lists and dictionaries.
5361  *
5362  * We use reference counts to be able to free most items right away when they
5363  * are no longer used.  But for composite items it's possible that it becomes
5364  * unused while the reference count is > 0: When there is a recursive
5365  * reference.  Example:
5366  *	:let l = [1, 2, 3]
5367  *	:let d = {9: l}
5368  *	:let l[1] = d
5369  *
5370  * Since this is quite unusual we handle this with garbage collection: every
5371  * once in a while find out which lists and dicts are not referenced from any
5372  * variable.
5373  *
5374  * Here is a good reference text about garbage collection (refers to Python
5375  * but it applies to all reference-counting mechanisms):
5376  *	http://python.ca/nas/python/gc/
5377  */
5378 
5379 /*
5380  * Do garbage collection for lists and dicts.
5381  * When "testing" is TRUE this is called from test_garbagecollect_now().
5382  * Return TRUE if some memory was freed.
5383  */
5384     int
5385 garbage_collect(int testing)
5386 {
5387     int		copyID;
5388     int		abort = FALSE;
5389     buf_T	*buf;
5390     win_T	*wp;
5391     int		i;
5392     int		did_free = FALSE;
5393     tabpage_T	*tp;
5394 
5395     if (!testing)
5396     {
5397 	/* Only do this once. */
5398 	want_garbage_collect = FALSE;
5399 	may_garbage_collect = FALSE;
5400 	garbage_collect_at_exit = FALSE;
5401     }
5402 
5403     /* We advance by two because we add one for items referenced through
5404      * previous_funccal. */
5405     copyID = get_copyID();
5406 
5407     /*
5408      * 1. Go through all accessible variables and mark all lists and dicts
5409      *    with copyID.
5410      */
5411 
5412     /* Don't free variables in the previous_funccal list unless they are only
5413      * referenced through previous_funccal.  This must be first, because if
5414      * the item is referenced elsewhere the funccal must not be freed. */
5415     abort = abort || set_ref_in_previous_funccal(copyID);
5416 
5417     /* script-local variables */
5418     for (i = 1; i <= ga_scripts.ga_len; ++i)
5419 	abort = abort || set_ref_in_ht(&SCRIPT_VARS(i), copyID, NULL);
5420 
5421     /* buffer-local variables */
5422     FOR_ALL_BUFFERS(buf)
5423 	abort = abort || set_ref_in_item(&buf->b_bufvar.di_tv, copyID,
5424 								  NULL, NULL);
5425 
5426     /* window-local variables */
5427     FOR_ALL_TAB_WINDOWS(tp, wp)
5428 	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
5429 								  NULL, NULL);
5430     if (aucmd_win != NULL)
5431 	abort = abort || set_ref_in_item(&aucmd_win->w_winvar.di_tv, copyID,
5432 								  NULL, NULL);
5433 
5434     /* tabpage-local variables */
5435     FOR_ALL_TABPAGES(tp)
5436 	abort = abort || set_ref_in_item(&tp->tp_winvar.di_tv, copyID,
5437 								  NULL, NULL);
5438     /* global variables */
5439     abort = abort || set_ref_in_ht(&globvarht, copyID, NULL);
5440 
5441     /* function-local variables */
5442     abort = abort || set_ref_in_call_stack(copyID);
5443 
5444     /* named functions (matters for closures) */
5445     abort = abort || set_ref_in_functions(copyID);
5446 
5447     /* function call arguments, if v:testing is set. */
5448     abort = abort || set_ref_in_func_args(copyID);
5449 
5450     /* v: vars */
5451     abort = abort || set_ref_in_ht(&vimvarht, copyID, NULL);
5452 
5453 #ifdef FEAT_LUA
5454     abort = abort || set_ref_in_lua(copyID);
5455 #endif
5456 
5457 #ifdef FEAT_PYTHON
5458     abort = abort || set_ref_in_python(copyID);
5459 #endif
5460 
5461 #ifdef FEAT_PYTHON3
5462     abort = abort || set_ref_in_python3(copyID);
5463 #endif
5464 
5465 #ifdef FEAT_JOB_CHANNEL
5466     abort = abort || set_ref_in_channel(copyID);
5467     abort = abort || set_ref_in_job(copyID);
5468 #endif
5469 #ifdef FEAT_NETBEANS_INTG
5470     abort = abort || set_ref_in_nb_channel(copyID);
5471 #endif
5472 
5473 #ifdef FEAT_TIMERS
5474     abort = abort || set_ref_in_timer(copyID);
5475 #endif
5476 
5477 #ifdef FEAT_QUICKFIX
5478     abort = abort || set_ref_in_quickfix(copyID);
5479 #endif
5480 
5481 #ifdef FEAT_TERMINAL
5482     abort = abort || set_ref_in_term(copyID);
5483 #endif
5484 
5485     if (!abort)
5486     {
5487 	/*
5488 	 * 2. Free lists and dictionaries that are not referenced.
5489 	 */
5490 	did_free = free_unref_items(copyID);
5491 
5492 	/*
5493 	 * 3. Check if any funccal can be freed now.
5494 	 *    This may call us back recursively.
5495 	 */
5496 	free_unref_funccal(copyID, testing);
5497     }
5498     else if (p_verbose > 0)
5499     {
5500 	verb_msg(_("Not enough memory to set references, garbage collection aborted!"));
5501     }
5502 
5503     return did_free;
5504 }
5505 
5506 /*
5507  * Free lists, dictionaries, channels and jobs that are no longer referenced.
5508  */
5509     static int
5510 free_unref_items(int copyID)
5511 {
5512     int		did_free = FALSE;
5513 
5514     /* Let all "free" functions know that we are here.  This means no
5515      * dictionaries, lists, channels or jobs are to be freed, because we will
5516      * do that here. */
5517     in_free_unref_items = TRUE;
5518 
5519     /*
5520      * PASS 1: free the contents of the items.  We don't free the items
5521      * themselves yet, so that it is possible to decrement refcount counters
5522      */
5523 
5524     /* Go through the list of dicts and free items without the copyID. */
5525     did_free |= dict_free_nonref(copyID);
5526 
5527     /* Go through the list of lists and free items without the copyID. */
5528     did_free |= list_free_nonref(copyID);
5529 
5530 #ifdef FEAT_JOB_CHANNEL
5531     /* Go through the list of jobs and free items without the copyID. This
5532      * must happen before doing channels, because jobs refer to channels, but
5533      * the reference from the channel to the job isn't tracked. */
5534     did_free |= free_unused_jobs_contents(copyID, COPYID_MASK);
5535 
5536     /* Go through the list of channels and free items without the copyID.  */
5537     did_free |= free_unused_channels_contents(copyID, COPYID_MASK);
5538 #endif
5539 
5540     /*
5541      * PASS 2: free the items themselves.
5542      */
5543     dict_free_items(copyID);
5544     list_free_items(copyID);
5545 
5546 #ifdef FEAT_JOB_CHANNEL
5547     /* Go through the list of jobs and free items without the copyID. This
5548      * must happen before doing channels, because jobs refer to channels, but
5549      * the reference from the channel to the job isn't tracked. */
5550     free_unused_jobs(copyID, COPYID_MASK);
5551 
5552     /* Go through the list of channels and free items without the copyID.  */
5553     free_unused_channels(copyID, COPYID_MASK);
5554 #endif
5555 
5556     in_free_unref_items = FALSE;
5557 
5558     return did_free;
5559 }
5560 
5561 /*
5562  * Mark all lists and dicts referenced through hashtab "ht" with "copyID".
5563  * "list_stack" is used to add lists to be marked.  Can be NULL.
5564  *
5565  * Returns TRUE if setting references failed somehow.
5566  */
5567     int
5568 set_ref_in_ht(hashtab_T *ht, int copyID, list_stack_T **list_stack)
5569 {
5570     int		todo;
5571     int		abort = FALSE;
5572     hashitem_T	*hi;
5573     hashtab_T	*cur_ht;
5574     ht_stack_T	*ht_stack = NULL;
5575     ht_stack_T	*tempitem;
5576 
5577     cur_ht = ht;
5578     for (;;)
5579     {
5580 	if (!abort)
5581 	{
5582 	    /* Mark each item in the hashtab.  If the item contains a hashtab
5583 	     * it is added to ht_stack, if it contains a list it is added to
5584 	     * list_stack. */
5585 	    todo = (int)cur_ht->ht_used;
5586 	    for (hi = cur_ht->ht_array; todo > 0; ++hi)
5587 		if (!HASHITEM_EMPTY(hi))
5588 		{
5589 		    --todo;
5590 		    abort = abort || set_ref_in_item(&HI2DI(hi)->di_tv, copyID,
5591 						       &ht_stack, list_stack);
5592 		}
5593 	}
5594 
5595 	if (ht_stack == NULL)
5596 	    break;
5597 
5598 	/* take an item from the stack */
5599 	cur_ht = ht_stack->ht;
5600 	tempitem = ht_stack;
5601 	ht_stack = ht_stack->prev;
5602 	free(tempitem);
5603     }
5604 
5605     return abort;
5606 }
5607 
5608 /*
5609  * Mark all lists and dicts referenced through list "l" with "copyID".
5610  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
5611  *
5612  * Returns TRUE if setting references failed somehow.
5613  */
5614     int
5615 set_ref_in_list(list_T *l, int copyID, ht_stack_T **ht_stack)
5616 {
5617     listitem_T	 *li;
5618     int		 abort = FALSE;
5619     list_T	 *cur_l;
5620     list_stack_T *list_stack = NULL;
5621     list_stack_T *tempitem;
5622 
5623     cur_l = l;
5624     for (;;)
5625     {
5626 	if (!abort)
5627 	    /* Mark each item in the list.  If the item contains a hashtab
5628 	     * it is added to ht_stack, if it contains a list it is added to
5629 	     * list_stack. */
5630 	    for (li = cur_l->lv_first; !abort && li != NULL; li = li->li_next)
5631 		abort = abort || set_ref_in_item(&li->li_tv, copyID,
5632 						       ht_stack, &list_stack);
5633 	if (list_stack == NULL)
5634 	    break;
5635 
5636 	/* take an item from the stack */
5637 	cur_l = list_stack->list;
5638 	tempitem = list_stack;
5639 	list_stack = list_stack->prev;
5640 	free(tempitem);
5641     }
5642 
5643     return abort;
5644 }
5645 
5646 /*
5647  * Mark all lists and dicts referenced through typval "tv" with "copyID".
5648  * "list_stack" is used to add lists to be marked.  Can be NULL.
5649  * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
5650  *
5651  * Returns TRUE if setting references failed somehow.
5652  */
5653     int
5654 set_ref_in_item(
5655     typval_T	    *tv,
5656     int		    copyID,
5657     ht_stack_T	    **ht_stack,
5658     list_stack_T    **list_stack)
5659 {
5660     int		abort = FALSE;
5661 
5662     if (tv->v_type == VAR_DICT)
5663     {
5664 	dict_T	*dd = tv->vval.v_dict;
5665 
5666 	if (dd != NULL && dd->dv_copyID != copyID)
5667 	{
5668 	    /* Didn't see this dict yet. */
5669 	    dd->dv_copyID = copyID;
5670 	    if (ht_stack == NULL)
5671 	    {
5672 		abort = set_ref_in_ht(&dd->dv_hashtab, copyID, list_stack);
5673 	    }
5674 	    else
5675 	    {
5676 		ht_stack_T *newitem = (ht_stack_T*)malloc(sizeof(ht_stack_T));
5677 		if (newitem == NULL)
5678 		    abort = TRUE;
5679 		else
5680 		{
5681 		    newitem->ht = &dd->dv_hashtab;
5682 		    newitem->prev = *ht_stack;
5683 		    *ht_stack = newitem;
5684 		}
5685 	    }
5686 	}
5687     }
5688     else if (tv->v_type == VAR_LIST)
5689     {
5690 	list_T	*ll = tv->vval.v_list;
5691 
5692 	if (ll != NULL && ll->lv_copyID != copyID)
5693 	{
5694 	    /* Didn't see this list yet. */
5695 	    ll->lv_copyID = copyID;
5696 	    if (list_stack == NULL)
5697 	    {
5698 		abort = set_ref_in_list(ll, copyID, ht_stack);
5699 	    }
5700 	    else
5701 	    {
5702 		list_stack_T *newitem = (list_stack_T*)malloc(
5703 							sizeof(list_stack_T));
5704 		if (newitem == NULL)
5705 		    abort = TRUE;
5706 		else
5707 		{
5708 		    newitem->list = ll;
5709 		    newitem->prev = *list_stack;
5710 		    *list_stack = newitem;
5711 		}
5712 	    }
5713 	}
5714     }
5715     else if (tv->v_type == VAR_FUNC)
5716     {
5717 	abort = set_ref_in_func(tv->vval.v_string, NULL, copyID);
5718     }
5719     else if (tv->v_type == VAR_PARTIAL)
5720     {
5721 	partial_T	*pt = tv->vval.v_partial;
5722 	int		i;
5723 
5724 	/* A partial does not have a copyID, because it cannot contain itself.
5725 	 */
5726 	if (pt != NULL)
5727 	{
5728 	    abort = set_ref_in_func(pt->pt_name, pt->pt_func, copyID);
5729 
5730 	    if (pt->pt_dict != NULL)
5731 	    {
5732 		typval_T dtv;
5733 
5734 		dtv.v_type = VAR_DICT;
5735 		dtv.vval.v_dict = pt->pt_dict;
5736 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5737 	    }
5738 
5739 	    for (i = 0; i < pt->pt_argc; ++i)
5740 		abort = abort || set_ref_in_item(&pt->pt_argv[i], copyID,
5741 							ht_stack, list_stack);
5742 	}
5743     }
5744 #ifdef FEAT_JOB_CHANNEL
5745     else if (tv->v_type == VAR_JOB)
5746     {
5747 	job_T	    *job = tv->vval.v_job;
5748 	typval_T    dtv;
5749 
5750 	if (job != NULL && job->jv_copyID != copyID)
5751 	{
5752 	    job->jv_copyID = copyID;
5753 	    if (job->jv_channel != NULL)
5754 	    {
5755 		dtv.v_type = VAR_CHANNEL;
5756 		dtv.vval.v_channel = job->jv_channel;
5757 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5758 	    }
5759 	    if (job->jv_exit_partial != NULL)
5760 	    {
5761 		dtv.v_type = VAR_PARTIAL;
5762 		dtv.vval.v_partial = job->jv_exit_partial;
5763 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5764 	    }
5765 	}
5766     }
5767     else if (tv->v_type == VAR_CHANNEL)
5768     {
5769 	channel_T   *ch =tv->vval.v_channel;
5770 	ch_part_T   part;
5771 	typval_T    dtv;
5772 	jsonq_T	    *jq;
5773 	cbq_T	    *cq;
5774 
5775 	if (ch != NULL && ch->ch_copyID != copyID)
5776 	{
5777 	    ch->ch_copyID = copyID;
5778 	    for (part = PART_SOCK; part < PART_COUNT; ++part)
5779 	    {
5780 		for (jq = ch->ch_part[part].ch_json_head.jq_next; jq != NULL;
5781 							     jq = jq->jq_next)
5782 		    set_ref_in_item(jq->jq_value, copyID, ht_stack, list_stack);
5783 		for (cq = ch->ch_part[part].ch_cb_head.cq_next; cq != NULL;
5784 							     cq = cq->cq_next)
5785 		    if (cq->cq_partial != NULL)
5786 		    {
5787 			dtv.v_type = VAR_PARTIAL;
5788 			dtv.vval.v_partial = cq->cq_partial;
5789 			set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5790 		    }
5791 		if (ch->ch_part[part].ch_partial != NULL)
5792 		{
5793 		    dtv.v_type = VAR_PARTIAL;
5794 		    dtv.vval.v_partial = ch->ch_part[part].ch_partial;
5795 		    set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5796 		}
5797 	    }
5798 	    if (ch->ch_partial != NULL)
5799 	    {
5800 		dtv.v_type = VAR_PARTIAL;
5801 		dtv.vval.v_partial = ch->ch_partial;
5802 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5803 	    }
5804 	    if (ch->ch_close_partial != NULL)
5805 	    {
5806 		dtv.v_type = VAR_PARTIAL;
5807 		dtv.vval.v_partial = ch->ch_close_partial;
5808 		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
5809 	    }
5810 	}
5811     }
5812 #endif
5813     return abort;
5814 }
5815 
5816     static char *
5817 get_var_special_name(int nr)
5818 {
5819     switch (nr)
5820     {
5821 	case VVAL_FALSE: return "v:false";
5822 	case VVAL_TRUE:  return "v:true";
5823 	case VVAL_NONE:  return "v:none";
5824 	case VVAL_NULL:  return "v:null";
5825     }
5826     internal_error("get_var_special_name()");
5827     return "42";
5828 }
5829 
5830 /*
5831  * Return a string with the string representation of a variable.
5832  * If the memory is allocated "tofree" is set to it, otherwise NULL.
5833  * "numbuf" is used for a number.
5834  * When "copyID" is not NULL replace recursive lists and dicts with "...".
5835  * When both "echo_style" and "composite_val" are FALSE, put quotes around
5836  * stings as "string()", otherwise does not put quotes around strings, as
5837  * ":echo" displays values.
5838  * When "restore_copyID" is FALSE, repeated items in dictionaries and lists
5839  * are replaced with "...".
5840  * May return NULL.
5841  */
5842     char_u *
5843 echo_string_core(
5844     typval_T	*tv,
5845     char_u	**tofree,
5846     char_u	*numbuf,
5847     int		copyID,
5848     int		echo_style,
5849     int		restore_copyID,
5850     int		composite_val)
5851 {
5852     static int	recurse = 0;
5853     char_u	*r = NULL;
5854 
5855     if (recurse >= DICT_MAXNEST)
5856     {
5857 	if (!did_echo_string_emsg)
5858 	{
5859 	    /* Only give this message once for a recursive call to avoid
5860 	     * flooding the user with errors.  And stop iterating over lists
5861 	     * and dicts. */
5862 	    did_echo_string_emsg = TRUE;
5863 	    emsg(_("E724: variable nested too deep for displaying"));
5864 	}
5865 	*tofree = NULL;
5866 	return (char_u *)"{E724}";
5867     }
5868     ++recurse;
5869 
5870     switch (tv->v_type)
5871     {
5872 	case VAR_STRING:
5873 	    if (echo_style && !composite_val)
5874 	    {
5875 		*tofree = NULL;
5876 		r = tv->vval.v_string;
5877 		if (r == NULL)
5878 		    r = (char_u *)"";
5879 	    }
5880 	    else
5881 	    {
5882 		*tofree = string_quote(tv->vval.v_string, FALSE);
5883 		r = *tofree;
5884 	    }
5885 	    break;
5886 
5887 	case VAR_FUNC:
5888 	    if (echo_style)
5889 	    {
5890 		*tofree = NULL;
5891 		r = tv->vval.v_string;
5892 	    }
5893 	    else
5894 	    {
5895 		*tofree = string_quote(tv->vval.v_string, TRUE);
5896 		r = *tofree;
5897 	    }
5898 	    break;
5899 
5900 	case VAR_PARTIAL:
5901 	    {
5902 		partial_T   *pt = tv->vval.v_partial;
5903 		char_u	    *fname = string_quote(pt == NULL ? NULL
5904 						    : partial_name(pt), FALSE);
5905 		garray_T    ga;
5906 		int	    i;
5907 		char_u	    *tf;
5908 
5909 		ga_init2(&ga, 1, 100);
5910 		ga_concat(&ga, (char_u *)"function(");
5911 		if (fname != NULL)
5912 		{
5913 		    ga_concat(&ga, fname);
5914 		    vim_free(fname);
5915 		}
5916 		if (pt != NULL && pt->pt_argc > 0)
5917 		{
5918 		    ga_concat(&ga, (char_u *)", [");
5919 		    for (i = 0; i < pt->pt_argc; ++i)
5920 		    {
5921 			if (i > 0)
5922 			    ga_concat(&ga, (char_u *)", ");
5923 			ga_concat(&ga,
5924 			     tv2string(&pt->pt_argv[i], &tf, numbuf, copyID));
5925 			vim_free(tf);
5926 		    }
5927 		    ga_concat(&ga, (char_u *)"]");
5928 		}
5929 		if (pt != NULL && pt->pt_dict != NULL)
5930 		{
5931 		    typval_T dtv;
5932 
5933 		    ga_concat(&ga, (char_u *)", ");
5934 		    dtv.v_type = VAR_DICT;
5935 		    dtv.vval.v_dict = pt->pt_dict;
5936 		    ga_concat(&ga, tv2string(&dtv, &tf, numbuf, copyID));
5937 		    vim_free(tf);
5938 		}
5939 		ga_concat(&ga, (char_u *)")");
5940 
5941 		*tofree = ga.ga_data;
5942 		r = *tofree;
5943 		break;
5944 	    }
5945 
5946 	case VAR_BLOB:
5947 	    r = blob2string(tv->vval.v_blob, tofree, numbuf);
5948 	    break;
5949 
5950 	case VAR_LIST:
5951 	    if (tv->vval.v_list == NULL)
5952 	    {
5953 		*tofree = NULL;
5954 		r = NULL;
5955 	    }
5956 	    else if (copyID != 0 && tv->vval.v_list->lv_copyID == copyID
5957 		    && tv->vval.v_list->lv_len > 0)
5958 	    {
5959 		*tofree = NULL;
5960 		r = (char_u *)"[...]";
5961 	    }
5962 	    else
5963 	    {
5964 		int old_copyID = tv->vval.v_list->lv_copyID;
5965 
5966 		tv->vval.v_list->lv_copyID = copyID;
5967 		*tofree = list2string(tv, copyID, restore_copyID);
5968 		if (restore_copyID)
5969 		    tv->vval.v_list->lv_copyID = old_copyID;
5970 		r = *tofree;
5971 	    }
5972 	    break;
5973 
5974 	case VAR_DICT:
5975 	    if (tv->vval.v_dict == NULL)
5976 	    {
5977 		*tofree = NULL;
5978 		r = NULL;
5979 	    }
5980 	    else if (copyID != 0 && tv->vval.v_dict->dv_copyID == copyID
5981 		    && tv->vval.v_dict->dv_hashtab.ht_used != 0)
5982 	    {
5983 		*tofree = NULL;
5984 		r = (char_u *)"{...}";
5985 	    }
5986 	    else
5987 	    {
5988 		int old_copyID = tv->vval.v_dict->dv_copyID;
5989 		tv->vval.v_dict->dv_copyID = copyID;
5990 		*tofree = dict2string(tv, copyID, restore_copyID);
5991 		if (restore_copyID)
5992 		    tv->vval.v_dict->dv_copyID = old_copyID;
5993 		r = *tofree;
5994 	    }
5995 	    break;
5996 
5997 	case VAR_NUMBER:
5998 	case VAR_UNKNOWN:
5999 	    *tofree = NULL;
6000 	    r = tv_get_string_buf(tv, numbuf);
6001 	    break;
6002 
6003 	case VAR_JOB:
6004 	case VAR_CHANNEL:
6005 	    *tofree = NULL;
6006 	    r = tv_get_string_buf(tv, numbuf);
6007 	    if (composite_val)
6008 	    {
6009 		*tofree = string_quote(r, FALSE);
6010 		r = *tofree;
6011 	    }
6012 	    break;
6013 
6014 	case VAR_FLOAT:
6015 #ifdef FEAT_FLOAT
6016 	    *tofree = NULL;
6017 	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv->vval.v_float);
6018 	    r = numbuf;
6019 	    break;
6020 #endif
6021 
6022 	case VAR_SPECIAL:
6023 	    *tofree = NULL;
6024 	    r = (char_u *)get_var_special_name(tv->vval.v_number);
6025 	    break;
6026     }
6027 
6028     if (--recurse == 0)
6029 	did_echo_string_emsg = FALSE;
6030     return r;
6031 }
6032 
6033 /*
6034  * Return a string with the string representation of a variable.
6035  * If the memory is allocated "tofree" is set to it, otherwise NULL.
6036  * "numbuf" is used for a number.
6037  * Does not put quotes around strings, as ":echo" displays values.
6038  * When "copyID" is not NULL replace recursive lists and dicts with "...".
6039  * May return NULL.
6040  */
6041     char_u *
6042 echo_string(
6043     typval_T	*tv,
6044     char_u	**tofree,
6045     char_u	*numbuf,
6046     int		copyID)
6047 {
6048     return echo_string_core(tv, tofree, numbuf, copyID, TRUE, FALSE, FALSE);
6049 }
6050 
6051 /*
6052  * Return a string with the string representation of a variable.
6053  * If the memory is allocated "tofree" is set to it, otherwise NULL.
6054  * "numbuf" is used for a number.
6055  * Puts quotes around strings, so that they can be parsed back by eval().
6056  * May return NULL.
6057  */
6058     char_u *
6059 tv2string(
6060     typval_T	*tv,
6061     char_u	**tofree,
6062     char_u	*numbuf,
6063     int		copyID)
6064 {
6065     return echo_string_core(tv, tofree, numbuf, copyID, FALSE, TRUE, FALSE);
6066 }
6067 
6068 /*
6069  * Return string "str" in ' quotes, doubling ' characters.
6070  * If "str" is NULL an empty string is assumed.
6071  * If "function" is TRUE make it function('string').
6072  */
6073     char_u *
6074 string_quote(char_u *str, int function)
6075 {
6076     unsigned	len;
6077     char_u	*p, *r, *s;
6078 
6079     len = (function ? 13 : 3);
6080     if (str != NULL)
6081     {
6082 	len += (unsigned)STRLEN(str);
6083 	for (p = str; *p != NUL; MB_PTR_ADV(p))
6084 	    if (*p == '\'')
6085 		++len;
6086     }
6087     s = r = alloc(len);
6088     if (r != NULL)
6089     {
6090 	if (function)
6091 	{
6092 	    STRCPY(r, "function('");
6093 	    r += 10;
6094 	}
6095 	else
6096 	    *r++ = '\'';
6097 	if (str != NULL)
6098 	    for (p = str; *p != NUL; )
6099 	    {
6100 		if (*p == '\'')
6101 		    *r++ = '\'';
6102 		MB_COPY_CHAR(p, r);
6103 	    }
6104 	*r++ = '\'';
6105 	if (function)
6106 	    *r++ = ')';
6107 	*r++ = NUL;
6108     }
6109     return s;
6110 }
6111 
6112 #if defined(FEAT_FLOAT) || defined(PROTO)
6113 /*
6114  * Convert the string "text" to a floating point number.
6115  * This uses strtod().  setlocale(LC_NUMERIC, "C") has been used to make sure
6116  * this always uses a decimal point.
6117  * Returns the length of the text that was consumed.
6118  */
6119     int
6120 string2float(
6121     char_u	*text,
6122     float_T	*value)	    /* result stored here */
6123 {
6124     char	*s = (char *)text;
6125     float_T	f;
6126 
6127     /* MS-Windows does not deal with "inf" and "nan" properly. */
6128     if (STRNICMP(text, "inf", 3) == 0)
6129     {
6130 	*value = INFINITY;
6131 	return 3;
6132     }
6133     if (STRNICMP(text, "-inf", 3) == 0)
6134     {
6135 	*value = -INFINITY;
6136 	return 4;
6137     }
6138     if (STRNICMP(text, "nan", 3) == 0)
6139     {
6140 	*value = NAN;
6141 	return 3;
6142     }
6143     f = strtod(s, &s);
6144     *value = f;
6145     return (int)((char_u *)s - text);
6146 }
6147 #endif
6148 
6149 /*
6150  * Get the value of an environment variable.
6151  * "arg" is pointing to the '$'.  It is advanced to after the name.
6152  * If the environment variable was not set, silently assume it is empty.
6153  * Return FAIL if the name is invalid.
6154  */
6155     static int
6156 get_env_tv(char_u **arg, typval_T *rettv, int evaluate)
6157 {
6158     char_u	*string = NULL;
6159     int		len;
6160     int		cc;
6161     char_u	*name;
6162     int		mustfree = FALSE;
6163 
6164     ++*arg;
6165     name = *arg;
6166     len = get_env_len(arg);
6167     if (evaluate)
6168     {
6169 	if (len == 0)
6170 	    return FAIL; /* invalid empty name */
6171 
6172 	cc = name[len];
6173 	name[len] = NUL;
6174 	/* first try vim_getenv(), fast for normal environment vars */
6175 	string = vim_getenv(name, &mustfree);
6176 	if (string != NULL && *string != NUL)
6177 	{
6178 	    if (!mustfree)
6179 		string = vim_strsave(string);
6180 	}
6181 	else
6182 	{
6183 	    if (mustfree)
6184 		vim_free(string);
6185 
6186 	    /* next try expanding things like $VIM and ${HOME} */
6187 	    string = expand_env_save(name - 1);
6188 	    if (string != NULL && *string == '$')
6189 		VIM_CLEAR(string);
6190 	}
6191 	name[len] = cc;
6192 
6193 	rettv->v_type = VAR_STRING;
6194 	rettv->vval.v_string = string;
6195     }
6196 
6197     return OK;
6198 }
6199 
6200 
6201 
6202 /*
6203  * Translate a String variable into a position.
6204  * Returns NULL when there is an error.
6205  */
6206     pos_T *
6207 var2fpos(
6208     typval_T	*varp,
6209     int		dollar_lnum,	/* TRUE when $ is last line */
6210     int		*fnum)		/* set to fnum for '0, 'A, etc. */
6211 {
6212     char_u		*name;
6213     static pos_T	pos;
6214     pos_T		*pp;
6215 
6216     /* Argument can be [lnum, col, coladd]. */
6217     if (varp->v_type == VAR_LIST)
6218     {
6219 	list_T		*l;
6220 	int		len;
6221 	int		error = FALSE;
6222 	listitem_T	*li;
6223 
6224 	l = varp->vval.v_list;
6225 	if (l == NULL)
6226 	    return NULL;
6227 
6228 	/* Get the line number */
6229 	pos.lnum = list_find_nr(l, 0L, &error);
6230 	if (error || pos.lnum <= 0 || pos.lnum > curbuf->b_ml.ml_line_count)
6231 	    return NULL;	/* invalid line number */
6232 
6233 	/* Get the column number */
6234 	pos.col = list_find_nr(l, 1L, &error);
6235 	if (error)
6236 	    return NULL;
6237 	len = (long)STRLEN(ml_get(pos.lnum));
6238 
6239 	/* We accept "$" for the column number: last column. */
6240 	li = list_find(l, 1L);
6241 	if (li != NULL && li->li_tv.v_type == VAR_STRING
6242 		&& li->li_tv.vval.v_string != NULL
6243 		&& STRCMP(li->li_tv.vval.v_string, "$") == 0)
6244 	    pos.col = len + 1;
6245 
6246 	/* Accept a position up to the NUL after the line. */
6247 	if (pos.col == 0 || (int)pos.col > len + 1)
6248 	    return NULL;	/* invalid column number */
6249 	--pos.col;
6250 
6251 	/* Get the virtual offset.  Defaults to zero. */
6252 	pos.coladd = list_find_nr(l, 2L, &error);
6253 	if (error)
6254 	    pos.coladd = 0;
6255 
6256 	return &pos;
6257     }
6258 
6259     name = tv_get_string_chk(varp);
6260     if (name == NULL)
6261 	return NULL;
6262     if (name[0] == '.')				/* cursor */
6263 	return &curwin->w_cursor;
6264     if (name[0] == 'v' && name[1] == NUL)	/* Visual start */
6265     {
6266 	if (VIsual_active)
6267 	    return &VIsual;
6268 	return &curwin->w_cursor;
6269     }
6270     if (name[0] == '\'')			/* mark */
6271     {
6272 	pp = getmark_buf_fnum(curbuf, name[1], FALSE, fnum);
6273 	if (pp == NULL || pp == (pos_T *)-1 || pp->lnum <= 0)
6274 	    return NULL;
6275 	return pp;
6276     }
6277 
6278     pos.coladd = 0;
6279 
6280     if (name[0] == 'w' && dollar_lnum)
6281     {
6282 	pos.col = 0;
6283 	if (name[1] == '0')		/* "w0": first visible line */
6284 	{
6285 	    update_topline();
6286 	    /* In silent Ex mode topline is zero, but that's not a valid line
6287 	     * number; use one instead. */
6288 	    pos.lnum = curwin->w_topline > 0 ? curwin->w_topline : 1;
6289 	    return &pos;
6290 	}
6291 	else if (name[1] == '$')	/* "w$": last visible line */
6292 	{
6293 	    validate_botline();
6294 	    /* In silent Ex mode botline is zero, return zero then. */
6295 	    pos.lnum = curwin->w_botline > 0 ? curwin->w_botline - 1 : 0;
6296 	    return &pos;
6297 	}
6298     }
6299     else if (name[0] == '$')		/* last column or line */
6300     {
6301 	if (dollar_lnum)
6302 	{
6303 	    pos.lnum = curbuf->b_ml.ml_line_count;
6304 	    pos.col = 0;
6305 	}
6306 	else
6307 	{
6308 	    pos.lnum = curwin->w_cursor.lnum;
6309 	    pos.col = (colnr_T)STRLEN(ml_get_curline());
6310 	}
6311 	return &pos;
6312     }
6313     return NULL;
6314 }
6315 
6316 /*
6317  * Convert list in "arg" into a position and optional file number.
6318  * When "fnump" is NULL there is no file number, only 3 items.
6319  * Note that the column is passed on as-is, the caller may want to decrement
6320  * it to use 1 for the first column.
6321  * Return FAIL when conversion is not possible, doesn't check the position for
6322  * validity.
6323  */
6324     int
6325 list2fpos(
6326     typval_T	*arg,
6327     pos_T	*posp,
6328     int		*fnump,
6329     colnr_T	*curswantp)
6330 {
6331     list_T	*l = arg->vval.v_list;
6332     long	i = 0;
6333     long	n;
6334 
6335     /* List must be: [fnum, lnum, col, coladd, curswant], where "fnum" is only
6336      * there when "fnump" isn't NULL; "coladd" and "curswant" are optional. */
6337     if (arg->v_type != VAR_LIST
6338 	    || l == NULL
6339 	    || l->lv_len < (fnump == NULL ? 2 : 3)
6340 	    || l->lv_len > (fnump == NULL ? 4 : 5))
6341 	return FAIL;
6342 
6343     if (fnump != NULL)
6344     {
6345 	n = list_find_nr(l, i++, NULL);	/* fnum */
6346 	if (n < 0)
6347 	    return FAIL;
6348 	if (n == 0)
6349 	    n = curbuf->b_fnum;		/* current buffer */
6350 	*fnump = n;
6351     }
6352 
6353     n = list_find_nr(l, i++, NULL);	/* lnum */
6354     if (n < 0)
6355 	return FAIL;
6356     posp->lnum = n;
6357 
6358     n = list_find_nr(l, i++, NULL);	/* col */
6359     if (n < 0)
6360 	return FAIL;
6361     posp->col = n;
6362 
6363     n = list_find_nr(l, i, NULL);	/* off */
6364     if (n < 0)
6365 	posp->coladd = 0;
6366     else
6367 	posp->coladd = n;
6368 
6369     if (curswantp != NULL)
6370 	*curswantp = list_find_nr(l, i + 1, NULL);  /* curswant */
6371 
6372     return OK;
6373 }
6374 
6375 /*
6376  * Get the length of an environment variable name.
6377  * Advance "arg" to the first character after the name.
6378  * Return 0 for error.
6379  */
6380     static int
6381 get_env_len(char_u **arg)
6382 {
6383     char_u	*p;
6384     int		len;
6385 
6386     for (p = *arg; vim_isIDc(*p); ++p)
6387 	;
6388     if (p == *arg)	    /* no name found */
6389 	return 0;
6390 
6391     len = (int)(p - *arg);
6392     *arg = p;
6393     return len;
6394 }
6395 
6396 /*
6397  * Get the length of the name of a function or internal variable.
6398  * "arg" is advanced to the first non-white character after the name.
6399  * Return 0 if something is wrong.
6400  */
6401     int
6402 get_id_len(char_u **arg)
6403 {
6404     char_u	*p;
6405     int		len;
6406 
6407     /* Find the end of the name. */
6408     for (p = *arg; eval_isnamec(*p); ++p)
6409     {
6410 	if (*p == ':')
6411 	{
6412 	    /* "s:" is start of "s:var", but "n:" is not and can be used in
6413 	     * slice "[n:]".  Also "xx:" is not a namespace. */
6414 	    len = (int)(p - *arg);
6415 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, **arg) == NULL)
6416 		    || len > 1)
6417 		break;
6418 	}
6419     }
6420     if (p == *arg)	    /* no name found */
6421 	return 0;
6422 
6423     len = (int)(p - *arg);
6424     *arg = skipwhite(p);
6425 
6426     return len;
6427 }
6428 
6429 /*
6430  * Get the length of the name of a variable or function.
6431  * Only the name is recognized, does not handle ".key" or "[idx]".
6432  * "arg" is advanced to the first non-white character after the name.
6433  * Return -1 if curly braces expansion failed.
6434  * Return 0 if something else is wrong.
6435  * If the name contains 'magic' {}'s, expand them and return the
6436  * expanded name in an allocated string via 'alias' - caller must free.
6437  */
6438     int
6439 get_name_len(
6440     char_u	**arg,
6441     char_u	**alias,
6442     int		evaluate,
6443     int		verbose)
6444 {
6445     int		len;
6446     char_u	*p;
6447     char_u	*expr_start;
6448     char_u	*expr_end;
6449 
6450     *alias = NULL;  /* default to no alias */
6451 
6452     if ((*arg)[0] == K_SPECIAL && (*arg)[1] == KS_EXTRA
6453 						  && (*arg)[2] == (int)KE_SNR)
6454     {
6455 	/* hard coded <SNR>, already translated */
6456 	*arg += 3;
6457 	return get_id_len(arg) + 3;
6458     }
6459     len = eval_fname_script(*arg);
6460     if (len > 0)
6461     {
6462 	/* literal "<SID>", "s:" or "<SNR>" */
6463 	*arg += len;
6464     }
6465 
6466     /*
6467      * Find the end of the name; check for {} construction.
6468      */
6469     p = find_name_end(*arg, &expr_start, &expr_end,
6470 					       len > 0 ? 0 : FNE_CHECK_START);
6471     if (expr_start != NULL)
6472     {
6473 	char_u	*temp_string;
6474 
6475 	if (!evaluate)
6476 	{
6477 	    len += (int)(p - *arg);
6478 	    *arg = skipwhite(p);
6479 	    return len;
6480 	}
6481 
6482 	/*
6483 	 * Include any <SID> etc in the expanded string:
6484 	 * Thus the -len here.
6485 	 */
6486 	temp_string = make_expanded_name(*arg - len, expr_start, expr_end, p);
6487 	if (temp_string == NULL)
6488 	    return -1;
6489 	*alias = temp_string;
6490 	*arg = skipwhite(p);
6491 	return (int)STRLEN(temp_string);
6492     }
6493 
6494     len += get_id_len(arg);
6495     // Only give an error when there is something, otherwise it will be
6496     // reported at a higher level.
6497     if (len == 0 && verbose && **arg != NUL)
6498 	semsg(_(e_invexpr2), *arg);
6499 
6500     return len;
6501 }
6502 
6503 /*
6504  * Find the end of a variable or function name, taking care of magic braces.
6505  * If "expr_start" is not NULL then "expr_start" and "expr_end" are set to the
6506  * start and end of the first magic braces item.
6507  * "flags" can have FNE_INCL_BR and FNE_CHECK_START.
6508  * Return a pointer to just after the name.  Equal to "arg" if there is no
6509  * valid name.
6510  */
6511     char_u *
6512 find_name_end(
6513     char_u	*arg,
6514     char_u	**expr_start,
6515     char_u	**expr_end,
6516     int		flags)
6517 {
6518     int		mb_nest = 0;
6519     int		br_nest = 0;
6520     char_u	*p;
6521     int		len;
6522 
6523     if (expr_start != NULL)
6524     {
6525 	*expr_start = NULL;
6526 	*expr_end = NULL;
6527     }
6528 
6529     /* Quick check for valid starting character. */
6530     if ((flags & FNE_CHECK_START) && !eval_isnamec1(*arg) && *arg != '{')
6531 	return arg;
6532 
6533     for (p = arg; *p != NUL
6534 		    && (eval_isnamec(*p)
6535 			|| *p == '{'
6536 			|| ((flags & FNE_INCL_BR) && (*p == '[' || *p == '.'))
6537 			|| mb_nest != 0
6538 			|| br_nest != 0); MB_PTR_ADV(p))
6539     {
6540 	if (*p == '\'')
6541 	{
6542 	    /* skip over 'string' to avoid counting [ and ] inside it. */
6543 	    for (p = p + 1; *p != NUL && *p != '\''; MB_PTR_ADV(p))
6544 		;
6545 	    if (*p == NUL)
6546 		break;
6547 	}
6548 	else if (*p == '"')
6549 	{
6550 	    /* skip over "str\"ing" to avoid counting [ and ] inside it. */
6551 	    for (p = p + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
6552 		if (*p == '\\' && p[1] != NUL)
6553 		    ++p;
6554 	    if (*p == NUL)
6555 		break;
6556 	}
6557 	else if (br_nest == 0 && mb_nest == 0 && *p == ':')
6558 	{
6559 	    /* "s:" is start of "s:var", but "n:" is not and can be used in
6560 	     * slice "[n:]".  Also "xx:" is not a namespace. But {ns}: is. */
6561 	    len = (int)(p - arg);
6562 	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, *arg) == NULL)
6563 		    || (len > 1 && p[-1] != '}'))
6564 		break;
6565 	}
6566 
6567 	if (mb_nest == 0)
6568 	{
6569 	    if (*p == '[')
6570 		++br_nest;
6571 	    else if (*p == ']')
6572 		--br_nest;
6573 	}
6574 
6575 	if (br_nest == 0)
6576 	{
6577 	    if (*p == '{')
6578 	    {
6579 		mb_nest++;
6580 		if (expr_start != NULL && *expr_start == NULL)
6581 		    *expr_start = p;
6582 	    }
6583 	    else if (*p == '}')
6584 	    {
6585 		mb_nest--;
6586 		if (expr_start != NULL && mb_nest == 0 && *expr_end == NULL)
6587 		    *expr_end = p;
6588 	    }
6589 	}
6590     }
6591 
6592     return p;
6593 }
6594 
6595 /*
6596  * Expands out the 'magic' {}'s in a variable/function name.
6597  * Note that this can call itself recursively, to deal with
6598  * constructs like foo{bar}{baz}{bam}
6599  * The four pointer arguments point to "foo{expre}ss{ion}bar"
6600  *			"in_start"      ^
6601  *			"expr_start"	   ^
6602  *			"expr_end"		 ^
6603  *			"in_end"			    ^
6604  *
6605  * Returns a new allocated string, which the caller must free.
6606  * Returns NULL for failure.
6607  */
6608     static char_u *
6609 make_expanded_name(
6610     char_u	*in_start,
6611     char_u	*expr_start,
6612     char_u	*expr_end,
6613     char_u	*in_end)
6614 {
6615     char_u	c1;
6616     char_u	*retval = NULL;
6617     char_u	*temp_result;
6618     char_u	*nextcmd = NULL;
6619 
6620     if (expr_end == NULL || in_end == NULL)
6621 	return NULL;
6622     *expr_start	= NUL;
6623     *expr_end = NUL;
6624     c1 = *in_end;
6625     *in_end = NUL;
6626 
6627     temp_result = eval_to_string(expr_start + 1, &nextcmd, FALSE);
6628     if (temp_result != NULL && nextcmd == NULL)
6629     {
6630 	retval = alloc((unsigned)(STRLEN(temp_result) + (expr_start - in_start)
6631 						   + (in_end - expr_end) + 1));
6632 	if (retval != NULL)
6633 	{
6634 	    STRCPY(retval, in_start);
6635 	    STRCAT(retval, temp_result);
6636 	    STRCAT(retval, expr_end + 1);
6637 	}
6638     }
6639     vim_free(temp_result);
6640 
6641     *in_end = c1;		/* put char back for error messages */
6642     *expr_start = '{';
6643     *expr_end = '}';
6644 
6645     if (retval != NULL)
6646     {
6647 	temp_result = find_name_end(retval, &expr_start, &expr_end, 0);
6648 	if (expr_start != NULL)
6649 	{
6650 	    /* Further expansion! */
6651 	    temp_result = make_expanded_name(retval, expr_start,
6652 						       expr_end, temp_result);
6653 	    vim_free(retval);
6654 	    retval = temp_result;
6655 	}
6656     }
6657 
6658     return retval;
6659 }
6660 
6661 /*
6662  * Return TRUE if character "c" can be used in a variable or function name.
6663  * Does not include '{' or '}' for magic braces.
6664  */
6665     int
6666 eval_isnamec(int c)
6667 {
6668     return (ASCII_ISALNUM(c) || c == '_' || c == ':' || c == AUTOLOAD_CHAR);
6669 }
6670 
6671 /*
6672  * Return TRUE if character "c" can be used as the first character in a
6673  * variable or function name (excluding '{' and '}').
6674  */
6675     int
6676 eval_isnamec1(int c)
6677 {
6678     return (ASCII_ISALPHA(c) || c == '_');
6679 }
6680 
6681 /*
6682  * Set number v: variable to "val".
6683  */
6684     void
6685 set_vim_var_nr(int idx, varnumber_T val)
6686 {
6687     vimvars[idx].vv_nr = val;
6688 }
6689 
6690 /*
6691  * Get number v: variable value.
6692  */
6693     varnumber_T
6694 get_vim_var_nr(int idx)
6695 {
6696     return vimvars[idx].vv_nr;
6697 }
6698 
6699 /*
6700  * Get string v: variable value.  Uses a static buffer, can only be used once.
6701  * If the String variable has never been set, return an empty string.
6702  * Never returns NULL;
6703  */
6704     char_u *
6705 get_vim_var_str(int idx)
6706 {
6707     return tv_get_string(&vimvars[idx].vv_tv);
6708 }
6709 
6710 /*
6711  * Get List v: variable value.  Caller must take care of reference count when
6712  * needed.
6713  */
6714     list_T *
6715 get_vim_var_list(int idx)
6716 {
6717     return vimvars[idx].vv_list;
6718 }
6719 
6720 /*
6721  * Get Dict v: variable value.  Caller must take care of reference count when
6722  * needed.
6723  */
6724     dict_T *
6725 get_vim_var_dict(int idx)
6726 {
6727     return vimvars[idx].vv_dict;
6728 }
6729 
6730 /*
6731  * Set v:char to character "c".
6732  */
6733     void
6734 set_vim_var_char(int c)
6735 {
6736     char_u	buf[MB_MAXBYTES + 1];
6737 
6738     if (has_mbyte)
6739 	buf[(*mb_char2bytes)(c, buf)] = NUL;
6740     else
6741     {
6742 	buf[0] = c;
6743 	buf[1] = NUL;
6744     }
6745     set_vim_var_string(VV_CHAR, buf, -1);
6746 }
6747 
6748 /*
6749  * Set v:count to "count" and v:count1 to "count1".
6750  * When "set_prevcount" is TRUE first set v:prevcount from v:count.
6751  */
6752     void
6753 set_vcount(
6754     long	count,
6755     long	count1,
6756     int		set_prevcount)
6757 {
6758     if (set_prevcount)
6759 	vimvars[VV_PREVCOUNT].vv_nr = vimvars[VV_COUNT].vv_nr;
6760     vimvars[VV_COUNT].vv_nr = count;
6761     vimvars[VV_COUNT1].vv_nr = count1;
6762 }
6763 
6764 /*
6765  * Save variables that might be changed as a side effect.  Used when executing
6766  * a timer callback.
6767  */
6768     void
6769 save_vimvars(vimvars_save_T *vvsave)
6770 {
6771     vvsave->vv_prevcount = vimvars[VV_PREVCOUNT].vv_nr;
6772     vvsave->vv_count = vimvars[VV_COUNT].vv_nr;
6773     vvsave->vv_count1 = vimvars[VV_COUNT1].vv_nr;
6774 }
6775 
6776 /*
6777  * Restore variables saved by save_vimvars().
6778  */
6779     void
6780 restore_vimvars(vimvars_save_T *vvsave)
6781 {
6782     vimvars[VV_PREVCOUNT].vv_nr = vvsave->vv_prevcount;
6783     vimvars[VV_COUNT].vv_nr = vvsave->vv_count;
6784     vimvars[VV_COUNT1].vv_nr = vvsave->vv_count1;
6785 }
6786 
6787 /*
6788  * Set string v: variable to a copy of "val".
6789  */
6790     void
6791 set_vim_var_string(
6792     int		idx,
6793     char_u	*val,
6794     int		len)	    /* length of "val" to use or -1 (whole string) */
6795 {
6796     clear_tv(&vimvars[idx].vv_di.di_tv);
6797     vimvars[idx].vv_type = VAR_STRING;
6798     if (val == NULL)
6799 	vimvars[idx].vv_str = NULL;
6800     else if (len == -1)
6801 	vimvars[idx].vv_str = vim_strsave(val);
6802     else
6803 	vimvars[idx].vv_str = vim_strnsave(val, len);
6804 }
6805 
6806 /*
6807  * Set List v: variable to "val".
6808  */
6809     void
6810 set_vim_var_list(int idx, list_T *val)
6811 {
6812     clear_tv(&vimvars[idx].vv_di.di_tv);
6813     vimvars[idx].vv_type = VAR_LIST;
6814     vimvars[idx].vv_list = val;
6815     if (val != NULL)
6816 	++val->lv_refcount;
6817 }
6818 
6819 /*
6820  * Set Dictionary v: variable to "val".
6821  */
6822     void
6823 set_vim_var_dict(int idx, dict_T *val)
6824 {
6825     clear_tv(&vimvars[idx].vv_di.di_tv);
6826     vimvars[idx].vv_type = VAR_DICT;
6827     vimvars[idx].vv_dict = val;
6828     if (val != NULL)
6829     {
6830 	++val->dv_refcount;
6831 	dict_set_items_ro(val);
6832     }
6833 }
6834 
6835 /*
6836  * Set v:register if needed.
6837  */
6838     void
6839 set_reg_var(int c)
6840 {
6841     char_u	regname;
6842 
6843     if (c == 0 || c == ' ')
6844 	regname = '"';
6845     else
6846 	regname = c;
6847     /* Avoid free/alloc when the value is already right. */
6848     if (vimvars[VV_REG].vv_str == NULL || vimvars[VV_REG].vv_str[0] != c)
6849 	set_vim_var_string(VV_REG, &regname, 1);
6850 }
6851 
6852 /*
6853  * Get or set v:exception.  If "oldval" == NULL, return the current value.
6854  * Otherwise, restore the value to "oldval" and return NULL.
6855  * Must always be called in pairs to save and restore v:exception!  Does not
6856  * take care of memory allocations.
6857  */
6858     char_u *
6859 v_exception(char_u *oldval)
6860 {
6861     if (oldval == NULL)
6862 	return vimvars[VV_EXCEPTION].vv_str;
6863 
6864     vimvars[VV_EXCEPTION].vv_str = oldval;
6865     return NULL;
6866 }
6867 
6868 /*
6869  * Get or set v:throwpoint.  If "oldval" == NULL, return the current value.
6870  * Otherwise, restore the value to "oldval" and return NULL.
6871  * Must always be called in pairs to save and restore v:throwpoint!  Does not
6872  * take care of memory allocations.
6873  */
6874     char_u *
6875 v_throwpoint(char_u *oldval)
6876 {
6877     if (oldval == NULL)
6878 	return vimvars[VV_THROWPOINT].vv_str;
6879 
6880     vimvars[VV_THROWPOINT].vv_str = oldval;
6881     return NULL;
6882 }
6883 
6884 /*
6885  * Set v:cmdarg.
6886  * If "eap" != NULL, use "eap" to generate the value and return the old value.
6887  * If "oldarg" != NULL, restore the value to "oldarg" and return NULL.
6888  * Must always be called in pairs!
6889  */
6890     char_u *
6891 set_cmdarg(exarg_T *eap, char_u *oldarg)
6892 {
6893     char_u	*oldval;
6894     char_u	*newval;
6895     unsigned	len;
6896 
6897     oldval = vimvars[VV_CMDARG].vv_str;
6898     if (eap == NULL)
6899     {
6900 	vim_free(oldval);
6901 	vimvars[VV_CMDARG].vv_str = oldarg;
6902 	return NULL;
6903     }
6904 
6905     if (eap->force_bin == FORCE_BIN)
6906 	len = 6;
6907     else if (eap->force_bin == FORCE_NOBIN)
6908 	len = 8;
6909     else
6910 	len = 0;
6911 
6912     if (eap->read_edit)
6913 	len += 7;
6914 
6915     if (eap->force_ff != 0)
6916 	len += 10; /* " ++ff=unix" */
6917     if (eap->force_enc != 0)
6918 	len += (unsigned)STRLEN(eap->cmd + eap->force_enc) + 7;
6919     if (eap->bad_char != 0)
6920 	len += 7 + 4;  /* " ++bad=" + "keep" or "drop" */
6921 
6922     newval = alloc(len + 1);
6923     if (newval == NULL)
6924 	return NULL;
6925 
6926     if (eap->force_bin == FORCE_BIN)
6927 	sprintf((char *)newval, " ++bin");
6928     else if (eap->force_bin == FORCE_NOBIN)
6929 	sprintf((char *)newval, " ++nobin");
6930     else
6931 	*newval = NUL;
6932 
6933     if (eap->read_edit)
6934 	STRCAT(newval, " ++edit");
6935 
6936     if (eap->force_ff != 0)
6937 	sprintf((char *)newval + STRLEN(newval), " ++ff=%s",
6938 						eap->force_ff == 'u' ? "unix"
6939 						: eap->force_ff == 'd' ? "dos"
6940 						: "mac");
6941     if (eap->force_enc != 0)
6942 	sprintf((char *)newval + STRLEN(newval), " ++enc=%s",
6943 					       eap->cmd + eap->force_enc);
6944     if (eap->bad_char == BAD_KEEP)
6945 	STRCPY(newval + STRLEN(newval), " ++bad=keep");
6946     else if (eap->bad_char == BAD_DROP)
6947 	STRCPY(newval + STRLEN(newval), " ++bad=drop");
6948     else if (eap->bad_char != 0)
6949 	sprintf((char *)newval + STRLEN(newval), " ++bad=%c", eap->bad_char);
6950     vimvars[VV_CMDARG].vv_str = newval;
6951     return oldval;
6952 }
6953 
6954 /*
6955  * Get the value of internal variable "name".
6956  * Return OK or FAIL.  If OK is returned "rettv" must be cleared.
6957  */
6958     int
6959 get_var_tv(
6960     char_u	*name,
6961     int		len,		/* length of "name" */
6962     typval_T	*rettv,		/* NULL when only checking existence */
6963     dictitem_T	**dip,		/* non-NULL when typval's dict item is needed */
6964     int		verbose,	/* may give error message */
6965     int		no_autoload)	/* do not use script autoloading */
6966 {
6967     int		ret = OK;
6968     typval_T	*tv = NULL;
6969     dictitem_T	*v;
6970     int		cc;
6971 
6972     /* truncate the name, so that we can use strcmp() */
6973     cc = name[len];
6974     name[len] = NUL;
6975 
6976     /*
6977      * Check for user-defined variables.
6978      */
6979     v = find_var(name, NULL, no_autoload);
6980     if (v != NULL)
6981     {
6982 	tv = &v->di_tv;
6983 	if (dip != NULL)
6984 	    *dip = v;
6985     }
6986 
6987     if (tv == NULL)
6988     {
6989 	if (rettv != NULL && verbose)
6990 	    semsg(_(e_undefvar), name);
6991 	ret = FAIL;
6992     }
6993     else if (rettv != NULL)
6994 	copy_tv(tv, rettv);
6995 
6996     name[len] = cc;
6997 
6998     return ret;
6999 }
7000 
7001 /*
7002  * Check if variable "name[len]" is a local variable or an argument.
7003  * If so, "*eval_lavars_used" is set to TRUE.
7004  */
7005     static void
7006 check_vars(char_u *name, int len)
7007 {
7008     int		cc;
7009     char_u	*varname;
7010     hashtab_T	*ht;
7011 
7012     if (eval_lavars_used == NULL)
7013 	return;
7014 
7015     /* truncate the name, so that we can use strcmp() */
7016     cc = name[len];
7017     name[len] = NUL;
7018 
7019     ht = find_var_ht(name, &varname);
7020     if (ht == get_funccal_local_ht() || ht == get_funccal_args_ht())
7021     {
7022 	if (find_var(name, NULL, TRUE) != NULL)
7023 	    *eval_lavars_used = TRUE;
7024     }
7025 
7026     name[len] = cc;
7027 }
7028 
7029 /*
7030  * Handle expr[expr], expr[expr:expr] subscript and .name lookup.
7031  * Also handle function call with Funcref variable: func(expr)
7032  * Can all be combined: dict.func(expr)[idx]['func'](expr)
7033  */
7034     int
7035 handle_subscript(
7036     char_u	**arg,
7037     typval_T	*rettv,
7038     int		evaluate,	/* do more than finding the end */
7039     int		verbose)	/* give error messages */
7040 {
7041     int		ret = OK;
7042     dict_T	*selfdict = NULL;
7043     char_u	*s;
7044     int		len;
7045     typval_T	functv;
7046 
7047     while (ret == OK
7048 	    && (**arg == '['
7049 		|| (**arg == '.' && rettv->v_type == VAR_DICT)
7050 		|| (**arg == '(' && (!evaluate || rettv->v_type == VAR_FUNC
7051 					    || rettv->v_type == VAR_PARTIAL)))
7052 	    && !VIM_ISWHITE(*(*arg - 1)))
7053     {
7054 	if (**arg == '(')
7055 	{
7056 	    partial_T	*pt = NULL;
7057 
7058 	    /* need to copy the funcref so that we can clear rettv */
7059 	    if (evaluate)
7060 	    {
7061 		functv = *rettv;
7062 		rettv->v_type = VAR_UNKNOWN;
7063 
7064 		/* Invoke the function.  Recursive! */
7065 		if (functv.v_type == VAR_PARTIAL)
7066 		{
7067 		    pt = functv.vval.v_partial;
7068 		    s = partial_name(pt);
7069 		}
7070 		else
7071 		    s = functv.vval.v_string;
7072 	    }
7073 	    else
7074 		s = (char_u *)"";
7075 	    ret = get_func_tv(s, (int)STRLEN(s), rettv, arg,
7076 			curwin->w_cursor.lnum, curwin->w_cursor.lnum,
7077 			&len, evaluate, pt, selfdict);
7078 
7079 	    /* Clear the funcref afterwards, so that deleting it while
7080 	     * evaluating the arguments is possible (see test55). */
7081 	    if (evaluate)
7082 		clear_tv(&functv);
7083 
7084 	    /* Stop the expression evaluation when immediately aborting on
7085 	     * error, or when an interrupt occurred or an exception was thrown
7086 	     * but not caught. */
7087 	    if (aborting())
7088 	    {
7089 		if (ret == OK)
7090 		    clear_tv(rettv);
7091 		ret = FAIL;
7092 	    }
7093 	    dict_unref(selfdict);
7094 	    selfdict = NULL;
7095 	}
7096 	else /* **arg == '[' || **arg == '.' */
7097 	{
7098 	    dict_unref(selfdict);
7099 	    if (rettv->v_type == VAR_DICT)
7100 	    {
7101 		selfdict = rettv->vval.v_dict;
7102 		if (selfdict != NULL)
7103 		    ++selfdict->dv_refcount;
7104 	    }
7105 	    else
7106 		selfdict = NULL;
7107 	    if (eval_index(arg, rettv, evaluate, verbose) == FAIL)
7108 	    {
7109 		clear_tv(rettv);
7110 		ret = FAIL;
7111 	    }
7112 	}
7113     }
7114 
7115     /* Turn "dict.Func" into a partial for "Func" bound to "dict".
7116      * Don't do this when "Func" is already a partial that was bound
7117      * explicitly (pt_auto is FALSE). */
7118     if (selfdict != NULL
7119 	    && (rettv->v_type == VAR_FUNC
7120 		|| (rettv->v_type == VAR_PARTIAL
7121 		    && (rettv->vval.v_partial->pt_auto
7122 			|| rettv->vval.v_partial->pt_dict == NULL))))
7123 	selfdict = make_partial(selfdict, rettv);
7124 
7125     dict_unref(selfdict);
7126     return ret;
7127 }
7128 
7129 /*
7130  * Allocate memory for a variable type-value, and make it empty (0 or NULL
7131  * value).
7132  */
7133     typval_T *
7134 alloc_tv(void)
7135 {
7136     return (typval_T *)alloc_clear((unsigned)sizeof(typval_T));
7137 }
7138 
7139 /*
7140  * Allocate memory for a variable type-value, and assign a string to it.
7141  * The string "s" must have been allocated, it is consumed.
7142  * Return NULL for out of memory, the variable otherwise.
7143  */
7144     static typval_T *
7145 alloc_string_tv(char_u *s)
7146 {
7147     typval_T	*rettv;
7148 
7149     rettv = alloc_tv();
7150     if (rettv != NULL)
7151     {
7152 	rettv->v_type = VAR_STRING;
7153 	rettv->vval.v_string = s;
7154     }
7155     else
7156 	vim_free(s);
7157     return rettv;
7158 }
7159 
7160 /*
7161  * Free the memory for a variable type-value.
7162  */
7163     void
7164 free_tv(typval_T *varp)
7165 {
7166     if (varp != NULL)
7167     {
7168 	switch (varp->v_type)
7169 	{
7170 	    case VAR_FUNC:
7171 		func_unref(varp->vval.v_string);
7172 		/* FALLTHROUGH */
7173 	    case VAR_STRING:
7174 		vim_free(varp->vval.v_string);
7175 		break;
7176 	    case VAR_PARTIAL:
7177 		partial_unref(varp->vval.v_partial);
7178 		break;
7179 	    case VAR_BLOB:
7180 		blob_unref(varp->vval.v_blob);
7181 		break;
7182 	    case VAR_LIST:
7183 		list_unref(varp->vval.v_list);
7184 		break;
7185 	    case VAR_DICT:
7186 		dict_unref(varp->vval.v_dict);
7187 		break;
7188 	    case VAR_JOB:
7189 #ifdef FEAT_JOB_CHANNEL
7190 		job_unref(varp->vval.v_job);
7191 		break;
7192 #endif
7193 	    case VAR_CHANNEL:
7194 #ifdef FEAT_JOB_CHANNEL
7195 		channel_unref(varp->vval.v_channel);
7196 		break;
7197 #endif
7198 	    case VAR_NUMBER:
7199 	    case VAR_FLOAT:
7200 	    case VAR_UNKNOWN:
7201 	    case VAR_SPECIAL:
7202 		break;
7203 	}
7204 	vim_free(varp);
7205     }
7206 }
7207 
7208 /*
7209  * Free the memory for a variable value and set the value to NULL or 0.
7210  */
7211     void
7212 clear_tv(typval_T *varp)
7213 {
7214     if (varp != NULL)
7215     {
7216 	switch (varp->v_type)
7217 	{
7218 	    case VAR_FUNC:
7219 		func_unref(varp->vval.v_string);
7220 		/* FALLTHROUGH */
7221 	    case VAR_STRING:
7222 		VIM_CLEAR(varp->vval.v_string);
7223 		break;
7224 	    case VAR_PARTIAL:
7225 		partial_unref(varp->vval.v_partial);
7226 		varp->vval.v_partial = NULL;
7227 		break;
7228 	    case VAR_BLOB:
7229 		blob_unref(varp->vval.v_blob);
7230 		varp->vval.v_blob = NULL;
7231 		break;
7232 	    case VAR_LIST:
7233 		list_unref(varp->vval.v_list);
7234 		varp->vval.v_list = NULL;
7235 		break;
7236 	    case VAR_DICT:
7237 		dict_unref(varp->vval.v_dict);
7238 		varp->vval.v_dict = NULL;
7239 		break;
7240 	    case VAR_NUMBER:
7241 	    case VAR_SPECIAL:
7242 		varp->vval.v_number = 0;
7243 		break;
7244 	    case VAR_FLOAT:
7245 #ifdef FEAT_FLOAT
7246 		varp->vval.v_float = 0.0;
7247 		break;
7248 #endif
7249 	    case VAR_JOB:
7250 #ifdef FEAT_JOB_CHANNEL
7251 		job_unref(varp->vval.v_job);
7252 		varp->vval.v_job = NULL;
7253 #endif
7254 		break;
7255 	    case VAR_CHANNEL:
7256 #ifdef FEAT_JOB_CHANNEL
7257 		channel_unref(varp->vval.v_channel);
7258 		varp->vval.v_channel = NULL;
7259 #endif
7260 	    case VAR_UNKNOWN:
7261 		break;
7262 	}
7263 	varp->v_lock = 0;
7264     }
7265 }
7266 
7267 /*
7268  * Set the value of a variable to NULL without freeing items.
7269  */
7270     void
7271 init_tv(typval_T *varp)
7272 {
7273     if (varp != NULL)
7274 	vim_memset(varp, 0, sizeof(typval_T));
7275 }
7276 
7277 /*
7278  * Get the number value of a variable.
7279  * If it is a String variable, uses vim_str2nr().
7280  * For incompatible types, return 0.
7281  * tv_get_number_chk() is similar to tv_get_number(), but informs the
7282  * caller of incompatible types: it sets *denote to TRUE if "denote"
7283  * is not NULL or returns -1 otherwise.
7284  */
7285     varnumber_T
7286 tv_get_number(typval_T *varp)
7287 {
7288     int		error = FALSE;
7289 
7290     return tv_get_number_chk(varp, &error);	/* return 0L on error */
7291 }
7292 
7293     varnumber_T
7294 tv_get_number_chk(typval_T *varp, int *denote)
7295 {
7296     varnumber_T	n = 0L;
7297 
7298     switch (varp->v_type)
7299     {
7300 	case VAR_NUMBER:
7301 	    return varp->vval.v_number;
7302 	case VAR_FLOAT:
7303 #ifdef FEAT_FLOAT
7304 	    emsg(_("E805: Using a Float as a Number"));
7305 	    break;
7306 #endif
7307 	case VAR_FUNC:
7308 	case VAR_PARTIAL:
7309 	    emsg(_("E703: Using a Funcref as a Number"));
7310 	    break;
7311 	case VAR_STRING:
7312 	    if (varp->vval.v_string != NULL)
7313 		vim_str2nr(varp->vval.v_string, NULL, NULL,
7314 						    STR2NR_ALL, &n, NULL, 0);
7315 	    return n;
7316 	case VAR_LIST:
7317 	    emsg(_("E745: Using a List as a Number"));
7318 	    break;
7319 	case VAR_DICT:
7320 	    emsg(_("E728: Using a Dictionary as a Number"));
7321 	    break;
7322 	case VAR_SPECIAL:
7323 	    return varp->vval.v_number == VVAL_TRUE ? 1 : 0;
7324 	    break;
7325 	case VAR_JOB:
7326 #ifdef FEAT_JOB_CHANNEL
7327 	    emsg(_("E910: Using a Job as a Number"));
7328 	    break;
7329 #endif
7330 	case VAR_CHANNEL:
7331 #ifdef FEAT_JOB_CHANNEL
7332 	    emsg(_("E913: Using a Channel as a Number"));
7333 	    break;
7334 #endif
7335 	case VAR_BLOB:
7336 	    emsg(_("E974: Using a Blob as a Number"));
7337 	    break;
7338 	case VAR_UNKNOWN:
7339 	    internal_error("tv_get_number(UNKNOWN)");
7340 	    break;
7341     }
7342     if (denote == NULL)		/* useful for values that must be unsigned */
7343 	n = -1;
7344     else
7345 	*denote = TRUE;
7346     return n;
7347 }
7348 
7349 #ifdef FEAT_FLOAT
7350     float_T
7351 tv_get_float(typval_T *varp)
7352 {
7353     switch (varp->v_type)
7354     {
7355 	case VAR_NUMBER:
7356 	    return (float_T)(varp->vval.v_number);
7357 	case VAR_FLOAT:
7358 	    return varp->vval.v_float;
7359 	case VAR_FUNC:
7360 	case VAR_PARTIAL:
7361 	    emsg(_("E891: Using a Funcref as a Float"));
7362 	    break;
7363 	case VAR_STRING:
7364 	    emsg(_("E892: Using a String as a Float"));
7365 	    break;
7366 	case VAR_LIST:
7367 	    emsg(_("E893: Using a List as a Float"));
7368 	    break;
7369 	case VAR_DICT:
7370 	    emsg(_("E894: Using a Dictionary as a Float"));
7371 	    break;
7372 	case VAR_SPECIAL:
7373 	    emsg(_("E907: Using a special value as a Float"));
7374 	    break;
7375 	case VAR_JOB:
7376 # ifdef FEAT_JOB_CHANNEL
7377 	    emsg(_("E911: Using a Job as a Float"));
7378 	    break;
7379 # endif
7380 	case VAR_CHANNEL:
7381 # ifdef FEAT_JOB_CHANNEL
7382 	    emsg(_("E914: Using a Channel as a Float"));
7383 	    break;
7384 # endif
7385 	case VAR_BLOB:
7386 	    emsg(_("E975: Using a Blob as a Float"));
7387 	    break;
7388 	case VAR_UNKNOWN:
7389 	    internal_error("tv_get_float(UNKNOWN)");
7390 	    break;
7391     }
7392     return 0;
7393 }
7394 #endif
7395 
7396 /*
7397  * Get the string value of a variable.
7398  * If it is a Number variable, the number is converted into a string.
7399  * tv_get_string() uses a single, static buffer.  YOU CAN ONLY USE IT ONCE!
7400  * tv_get_string_buf() uses a given buffer.
7401  * If the String variable has never been set, return an empty string.
7402  * Never returns NULL;
7403  * tv_get_string_chk() and tv_get_string_buf_chk() are similar, but return
7404  * NULL on error.
7405  */
7406     char_u *
7407 tv_get_string(typval_T *varp)
7408 {
7409     static char_u   mybuf[NUMBUFLEN];
7410 
7411     return tv_get_string_buf(varp, mybuf);
7412 }
7413 
7414     char_u *
7415 tv_get_string_buf(typval_T *varp, char_u *buf)
7416 {
7417     char_u	*res =  tv_get_string_buf_chk(varp, buf);
7418 
7419     return res != NULL ? res : (char_u *)"";
7420 }
7421 
7422 /*
7423  * Careful: This uses a single, static buffer.  YOU CAN ONLY USE IT ONCE!
7424  */
7425     char_u *
7426 tv_get_string_chk(typval_T *varp)
7427 {
7428     static char_u   mybuf[NUMBUFLEN];
7429 
7430     return tv_get_string_buf_chk(varp, mybuf);
7431 }
7432 
7433     char_u *
7434 tv_get_string_buf_chk(typval_T *varp, char_u *buf)
7435 {
7436     switch (varp->v_type)
7437     {
7438 	case VAR_NUMBER:
7439 	    vim_snprintf((char *)buf, NUMBUFLEN, "%lld",
7440 					    (long_long_T)varp->vval.v_number);
7441 	    return buf;
7442 	case VAR_FUNC:
7443 	case VAR_PARTIAL:
7444 	    emsg(_("E729: using Funcref as a String"));
7445 	    break;
7446 	case VAR_LIST:
7447 	    emsg(_("E730: using List as a String"));
7448 	    break;
7449 	case VAR_DICT:
7450 	    emsg(_("E731: using Dictionary as a String"));
7451 	    break;
7452 	case VAR_FLOAT:
7453 #ifdef FEAT_FLOAT
7454 	    emsg(_(e_float_as_string));
7455 	    break;
7456 #endif
7457 	case VAR_STRING:
7458 	    if (varp->vval.v_string != NULL)
7459 		return varp->vval.v_string;
7460 	    return (char_u *)"";
7461 	case VAR_SPECIAL:
7462 	    STRCPY(buf, get_var_special_name(varp->vval.v_number));
7463 	    return buf;
7464         case VAR_BLOB:
7465 	    emsg(_("E976: using Blob as a String"));
7466 	    break;
7467 	case VAR_JOB:
7468 #ifdef FEAT_JOB_CHANNEL
7469 	    {
7470 		job_T *job = varp->vval.v_job;
7471 		char  *status;
7472 
7473 		if (job == NULL)
7474 		    return (char_u *)"no process";
7475 		status = job->jv_status == JOB_FAILED ? "fail"
7476 				: job->jv_status >= JOB_ENDED ? "dead"
7477 				: "run";
7478 # ifdef UNIX
7479 		vim_snprintf((char *)buf, NUMBUFLEN,
7480 			    "process %ld %s", (long)job->jv_pid, status);
7481 # elif defined(MSWIN)
7482 		vim_snprintf((char *)buf, NUMBUFLEN,
7483 			    "process %ld %s",
7484 			    (long)job->jv_proc_info.dwProcessId,
7485 			    status);
7486 # else
7487 		/* fall-back */
7488 		vim_snprintf((char *)buf, NUMBUFLEN, "process ? %s", status);
7489 # endif
7490 		return buf;
7491 	    }
7492 #endif
7493 	    break;
7494 	case VAR_CHANNEL:
7495 #ifdef FEAT_JOB_CHANNEL
7496 	    {
7497 		channel_T *channel = varp->vval.v_channel;
7498 		char      *status = channel_status(channel, -1);
7499 
7500 		if (channel == NULL)
7501 		    vim_snprintf((char *)buf, NUMBUFLEN, "channel %s", status);
7502 		else
7503 		    vim_snprintf((char *)buf, NUMBUFLEN,
7504 				     "channel %d %s", channel->ch_id, status);
7505 		return buf;
7506 	    }
7507 #endif
7508 	    break;
7509 	case VAR_UNKNOWN:
7510 	    emsg(_("E908: using an invalid value as a String"));
7511 	    break;
7512     }
7513     return NULL;
7514 }
7515 
7516 /*
7517  * Turn a typeval into a string.  Similar to tv_get_string_buf() but uses
7518  * string() on Dict, List, etc.
7519  */
7520     char_u *
7521 tv_stringify(typval_T *varp, char_u *buf)
7522 {
7523     if (varp->v_type == VAR_LIST
7524 	    || varp->v_type == VAR_DICT
7525 	    || varp->v_type == VAR_FUNC
7526 	    || varp->v_type == VAR_PARTIAL
7527 	    || varp->v_type == VAR_FLOAT)
7528     {
7529 	typval_T tmp;
7530 
7531 	f_string(varp, &tmp);
7532 	tv_get_string_buf(&tmp, buf);
7533 	clear_tv(varp);
7534 	*varp = tmp;
7535 	return tmp.vval.v_string;
7536     }
7537     return tv_get_string_buf(varp, buf);
7538 }
7539 
7540 /*
7541  * Find variable "name" in the list of variables.
7542  * Return a pointer to it if found, NULL if not found.
7543  * Careful: "a:0" variables don't have a name.
7544  * When "htp" is not NULL we are writing to the variable, set "htp" to the
7545  * hashtab_T used.
7546  */
7547     dictitem_T *
7548 find_var(char_u *name, hashtab_T **htp, int no_autoload)
7549 {
7550     char_u	*varname;
7551     hashtab_T	*ht;
7552     dictitem_T	*ret = NULL;
7553 
7554     ht = find_var_ht(name, &varname);
7555     if (htp != NULL)
7556 	*htp = ht;
7557     if (ht == NULL)
7558 	return NULL;
7559     ret = find_var_in_ht(ht, *name, varname, no_autoload || htp != NULL);
7560     if (ret != NULL)
7561 	return ret;
7562 
7563     /* Search in parent scope for lambda */
7564     return find_var_in_scoped_ht(name, no_autoload || htp != NULL);
7565 }
7566 
7567 /*
7568  * Find variable "varname" in hashtab "ht" with name "htname".
7569  * Returns NULL if not found.
7570  */
7571     dictitem_T *
7572 find_var_in_ht(
7573     hashtab_T	*ht,
7574     int		htname,
7575     char_u	*varname,
7576     int		no_autoload)
7577 {
7578     hashitem_T	*hi;
7579 
7580     if (*varname == NUL)
7581     {
7582 	/* Must be something like "s:", otherwise "ht" would be NULL. */
7583 	switch (htname)
7584 	{
7585 	    case 's': return &SCRIPT_SV(current_sctx.sc_sid)->sv_var;
7586 	    case 'g': return &globvars_var;
7587 	    case 'v': return &vimvars_var;
7588 	    case 'b': return &curbuf->b_bufvar;
7589 	    case 'w': return &curwin->w_winvar;
7590 	    case 't': return &curtab->tp_winvar;
7591 	    case 'l': return get_funccal_local_var();
7592 	    case 'a': return get_funccal_args_var();
7593 	}
7594 	return NULL;
7595     }
7596 
7597     hi = hash_find(ht, varname);
7598     if (HASHITEM_EMPTY(hi))
7599     {
7600 	/* For global variables we may try auto-loading the script.  If it
7601 	 * worked find the variable again.  Don't auto-load a script if it was
7602 	 * loaded already, otherwise it would be loaded every time when
7603 	 * checking if a function name is a Funcref variable. */
7604 	if (ht == &globvarht && !no_autoload)
7605 	{
7606 	    /* Note: script_autoload() may make "hi" invalid. It must either
7607 	     * be obtained again or not used. */
7608 	    if (!script_autoload(varname, FALSE) || aborting())
7609 		return NULL;
7610 	    hi = hash_find(ht, varname);
7611 	}
7612 	if (HASHITEM_EMPTY(hi))
7613 	    return NULL;
7614     }
7615     return HI2DI(hi);
7616 }
7617 
7618 /*
7619  * Find the hashtab used for a variable name.
7620  * Return NULL if the name is not valid.
7621  * Set "varname" to the start of name without ':'.
7622  */
7623     hashtab_T *
7624 find_var_ht(char_u *name, char_u **varname)
7625 {
7626     hashitem_T	*hi;
7627     hashtab_T	*ht;
7628 
7629     if (name[0] == NUL)
7630 	return NULL;
7631     if (name[1] != ':')
7632     {
7633 	/* The name must not start with a colon or #. */
7634 	if (name[0] == ':' || name[0] == AUTOLOAD_CHAR)
7635 	    return NULL;
7636 	*varname = name;
7637 
7638 	/* "version" is "v:version" in all scopes */
7639 	hi = hash_find(&compat_hashtab, name);
7640 	if (!HASHITEM_EMPTY(hi))
7641 	    return &compat_hashtab;
7642 
7643 	ht = get_funccal_local_ht();
7644 	if (ht == NULL)
7645 	    return &globvarht;			/* global variable */
7646 	return ht;				/* local variable */
7647     }
7648     *varname = name + 2;
7649     if (*name == 'g')				/* global variable */
7650 	return &globvarht;
7651     /* There must be no ':' or '#' in the rest of the name, unless g: is used
7652      */
7653     if (vim_strchr(name + 2, ':') != NULL
7654 			       || vim_strchr(name + 2, AUTOLOAD_CHAR) != NULL)
7655 	return NULL;
7656     if (*name == 'b')				/* buffer variable */
7657 	return &curbuf->b_vars->dv_hashtab;
7658     if (*name == 'w')				/* window variable */
7659 	return &curwin->w_vars->dv_hashtab;
7660     if (*name == 't')				/* tab page variable */
7661 	return &curtab->tp_vars->dv_hashtab;
7662     if (*name == 'v')				/* v: variable */
7663 	return &vimvarht;
7664     if (*name == 'a')				/* a: function argument */
7665 	return get_funccal_args_ht();
7666     if (*name == 'l')				/* l: local function variable */
7667 	return get_funccal_local_ht();
7668     if (*name == 's'				/* script variable */
7669 	    && current_sctx.sc_sid > 0 && current_sctx.sc_sid <= ga_scripts.ga_len)
7670 	return &SCRIPT_VARS(current_sctx.sc_sid);
7671     return NULL;
7672 }
7673 
7674 /*
7675  * Get the string value of a (global/local) variable.
7676  * Note: see tv_get_string() for how long the pointer remains valid.
7677  * Returns NULL when it doesn't exist.
7678  */
7679     char_u *
7680 get_var_value(char_u *name)
7681 {
7682     dictitem_T	*v;
7683 
7684     v = find_var(name, NULL, FALSE);
7685     if (v == NULL)
7686 	return NULL;
7687     return tv_get_string(&v->di_tv);
7688 }
7689 
7690 /*
7691  * Allocate a new hashtab for a sourced script.  It will be used while
7692  * sourcing this script and when executing functions defined in the script.
7693  */
7694     void
7695 new_script_vars(scid_T id)
7696 {
7697     int		i;
7698     hashtab_T	*ht;
7699     scriptvar_T *sv;
7700 
7701     if (ga_grow(&ga_scripts, (int)(id - ga_scripts.ga_len)) == OK)
7702     {
7703 	/* Re-allocating ga_data means that an ht_array pointing to
7704 	 * ht_smallarray becomes invalid.  We can recognize this: ht_mask is
7705 	 * at its init value.  Also reset "v_dict", it's always the same. */
7706 	for (i = 1; i <= ga_scripts.ga_len; ++i)
7707 	{
7708 	    ht = &SCRIPT_VARS(i);
7709 	    if (ht->ht_mask == HT_INIT_SIZE - 1)
7710 		ht->ht_array = ht->ht_smallarray;
7711 	    sv = SCRIPT_SV(i);
7712 	    sv->sv_var.di_tv.vval.v_dict = &sv->sv_dict;
7713 	}
7714 
7715 	while (ga_scripts.ga_len < id)
7716 	{
7717 	    sv = SCRIPT_SV(ga_scripts.ga_len + 1) =
7718 		(scriptvar_T *)alloc_clear(sizeof(scriptvar_T));
7719 	    init_var_dict(&sv->sv_dict, &sv->sv_var, VAR_SCOPE);
7720 	    ++ga_scripts.ga_len;
7721 	}
7722     }
7723 }
7724 
7725 /*
7726  * Initialize dictionary "dict" as a scope and set variable "dict_var" to
7727  * point to it.
7728  */
7729     void
7730 init_var_dict(dict_T *dict, dictitem_T *dict_var, int scope)
7731 {
7732     hash_init(&dict->dv_hashtab);
7733     dict->dv_lock = 0;
7734     dict->dv_scope = scope;
7735     dict->dv_refcount = DO_NOT_FREE_CNT;
7736     dict->dv_copyID = 0;
7737     dict_var->di_tv.vval.v_dict = dict;
7738     dict_var->di_tv.v_type = VAR_DICT;
7739     dict_var->di_tv.v_lock = VAR_FIXED;
7740     dict_var->di_flags = DI_FLAGS_RO | DI_FLAGS_FIX;
7741     dict_var->di_key[0] = NUL;
7742 }
7743 
7744 /*
7745  * Unreference a dictionary initialized by init_var_dict().
7746  */
7747     void
7748 unref_var_dict(dict_T *dict)
7749 {
7750     /* Now the dict needs to be freed if no one else is using it, go back to
7751      * normal reference counting. */
7752     dict->dv_refcount -= DO_NOT_FREE_CNT - 1;
7753     dict_unref(dict);
7754 }
7755 
7756 /*
7757  * Clean up a list of internal variables.
7758  * Frees all allocated variables and the value they contain.
7759  * Clears hashtab "ht", does not free it.
7760  */
7761     void
7762 vars_clear(hashtab_T *ht)
7763 {
7764     vars_clear_ext(ht, TRUE);
7765 }
7766 
7767 /*
7768  * Like vars_clear(), but only free the value if "free_val" is TRUE.
7769  */
7770     void
7771 vars_clear_ext(hashtab_T *ht, int free_val)
7772 {
7773     int		todo;
7774     hashitem_T	*hi;
7775     dictitem_T	*v;
7776 
7777     hash_lock(ht);
7778     todo = (int)ht->ht_used;
7779     for (hi = ht->ht_array; todo > 0; ++hi)
7780     {
7781 	if (!HASHITEM_EMPTY(hi))
7782 	{
7783 	    --todo;
7784 
7785 	    /* Free the variable.  Don't remove it from the hashtab,
7786 	     * ht_array might change then.  hash_clear() takes care of it
7787 	     * later. */
7788 	    v = HI2DI(hi);
7789 	    if (free_val)
7790 		clear_tv(&v->di_tv);
7791 	    if (v->di_flags & DI_FLAGS_ALLOC)
7792 		vim_free(v);
7793 	}
7794     }
7795     hash_clear(ht);
7796     ht->ht_used = 0;
7797 }
7798 
7799 /*
7800  * Delete a variable from hashtab "ht" at item "hi".
7801  * Clear the variable value and free the dictitem.
7802  */
7803     static void
7804 delete_var(hashtab_T *ht, hashitem_T *hi)
7805 {
7806     dictitem_T	*di = HI2DI(hi);
7807 
7808     hash_remove(ht, hi);
7809     clear_tv(&di->di_tv);
7810     vim_free(di);
7811 }
7812 
7813 /*
7814  * List the value of one internal variable.
7815  */
7816     static void
7817 list_one_var(dictitem_T *v, char *prefix, int *first)
7818 {
7819     char_u	*tofree;
7820     char_u	*s;
7821     char_u	numbuf[NUMBUFLEN];
7822 
7823     s = echo_string(&v->di_tv, &tofree, numbuf, get_copyID());
7824     list_one_var_a(prefix, v->di_key, v->di_tv.v_type,
7825 					 s == NULL ? (char_u *)"" : s, first);
7826     vim_free(tofree);
7827 }
7828 
7829     static void
7830 list_one_var_a(
7831     char	*prefix,
7832     char_u	*name,
7833     int		type,
7834     char_u	*string,
7835     int		*first)  /* when TRUE clear rest of screen and set to FALSE */
7836 {
7837     /* don't use msg() or msg_attr() to avoid overwriting "v:statusmsg" */
7838     msg_start();
7839     msg_puts(prefix);
7840     if (name != NULL)	/* "a:" vars don't have a name stored */
7841 	msg_puts((char *)name);
7842     msg_putchar(' ');
7843     msg_advance(22);
7844     if (type == VAR_NUMBER)
7845 	msg_putchar('#');
7846     else if (type == VAR_FUNC || type == VAR_PARTIAL)
7847 	msg_putchar('*');
7848     else if (type == VAR_LIST)
7849     {
7850 	msg_putchar('[');
7851 	if (*string == '[')
7852 	    ++string;
7853     }
7854     else if (type == VAR_DICT)
7855     {
7856 	msg_putchar('{');
7857 	if (*string == '{')
7858 	    ++string;
7859     }
7860     else
7861 	msg_putchar(' ');
7862 
7863     msg_outtrans(string);
7864 
7865     if (type == VAR_FUNC || type == VAR_PARTIAL)
7866 	msg_puts("()");
7867     if (*first)
7868     {
7869 	msg_clr_eos();
7870 	*first = FALSE;
7871     }
7872 }
7873 
7874 /*
7875  * Set variable "name" to value in "tv".
7876  * If the variable already exists, the value is updated.
7877  * Otherwise the variable is created.
7878  */
7879     void
7880 set_var(
7881     char_u	*name,
7882     typval_T	*tv,
7883     int		copy)	    /* make copy of value in "tv" */
7884 {
7885     dictitem_T	*v;
7886     char_u	*varname;
7887     hashtab_T	*ht;
7888 
7889     ht = find_var_ht(name, &varname);
7890     if (ht == NULL || *varname == NUL)
7891     {
7892 	semsg(_(e_illvar), name);
7893 	return;
7894     }
7895     v = find_var_in_ht(ht, 0, varname, TRUE);
7896 
7897     /* Search in parent scope which is possible to reference from lambda */
7898     if (v == NULL)
7899 	v = find_var_in_scoped_ht(name, TRUE);
7900 
7901     if ((tv->v_type == VAR_FUNC || tv->v_type == VAR_PARTIAL)
7902 				      && var_check_func_name(name, v == NULL))
7903 	return;
7904 
7905     if (v != NULL)
7906     {
7907 	/* existing variable, need to clear the value */
7908 	if (var_check_ro(v->di_flags, name, FALSE)
7909 			      || var_check_lock(v->di_tv.v_lock, name, FALSE))
7910 	    return;
7911 
7912 	/*
7913 	 * Handle setting internal v: variables separately where needed to
7914 	 * prevent changing the type.
7915 	 */
7916 	if (ht == &vimvarht)
7917 	{
7918 	    if (v->di_tv.v_type == VAR_STRING)
7919 	    {
7920 		VIM_CLEAR(v->di_tv.vval.v_string);
7921 		if (copy || tv->v_type != VAR_STRING)
7922 		{
7923 		    char_u *val = tv_get_string(tv);
7924 
7925 		    // Careful: when assigning to v:errmsg and tv_get_string()
7926 		    // causes an error message the variable will alrady be set.
7927 		    if (v->di_tv.vval.v_string == NULL)
7928 			v->di_tv.vval.v_string = vim_strsave(val);
7929 		}
7930 		else
7931 		{
7932 		    /* Take over the string to avoid an extra alloc/free. */
7933 		    v->di_tv.vval.v_string = tv->vval.v_string;
7934 		    tv->vval.v_string = NULL;
7935 		}
7936 		return;
7937 	    }
7938 	    else if (v->di_tv.v_type == VAR_NUMBER)
7939 	    {
7940 		v->di_tv.vval.v_number = tv_get_number(tv);
7941 		if (STRCMP(varname, "searchforward") == 0)
7942 		    set_search_direction(v->di_tv.vval.v_number ? '/' : '?');
7943 #ifdef FEAT_SEARCH_EXTRA
7944 		else if (STRCMP(varname, "hlsearch") == 0)
7945 		{
7946 		    no_hlsearch = !v->di_tv.vval.v_number;
7947 		    redraw_all_later(SOME_VALID);
7948 		}
7949 #endif
7950 		return;
7951 	    }
7952 	    else if (v->di_tv.v_type != tv->v_type)
7953 	    {
7954 		semsg(_("E963: setting %s to value with wrong type"), name);
7955 		return;
7956 	    }
7957 	}
7958 
7959 	clear_tv(&v->di_tv);
7960     }
7961     else		    /* add a new variable */
7962     {
7963 	// Can't add "v:" or "a:" variable.
7964 	if (ht == &vimvarht || ht == get_funccal_args_ht())
7965 	{
7966 	    semsg(_(e_illvar), name);
7967 	    return;
7968 	}
7969 
7970 	// Make sure the variable name is valid.
7971 	if (!valid_varname(varname))
7972 	    return;
7973 
7974 	v = (dictitem_T *)alloc((unsigned)(sizeof(dictitem_T)
7975 							  + STRLEN(varname)));
7976 	if (v == NULL)
7977 	    return;
7978 	STRCPY(v->di_key, varname);
7979 	if (hash_add(ht, DI2HIKEY(v)) == FAIL)
7980 	{
7981 	    vim_free(v);
7982 	    return;
7983 	}
7984 	v->di_flags = DI_FLAGS_ALLOC;
7985     }
7986 
7987     if (copy || tv->v_type == VAR_NUMBER || tv->v_type == VAR_FLOAT)
7988 	copy_tv(tv, &v->di_tv);
7989     else
7990     {
7991 	v->di_tv = *tv;
7992 	v->di_tv.v_lock = 0;
7993 	init_tv(tv);
7994     }
7995 }
7996 
7997 /*
7998  * Return TRUE if di_flags "flags" indicates variable "name" is read-only.
7999  * Also give an error message.
8000  */
8001     int
8002 var_check_ro(int flags, char_u *name, int use_gettext)
8003 {
8004     if (flags & DI_FLAGS_RO)
8005     {
8006 	semsg(_(e_readonlyvar), use_gettext ? (char_u *)_(name) : name);
8007 	return TRUE;
8008     }
8009     if ((flags & DI_FLAGS_RO_SBX) && sandbox)
8010     {
8011 	semsg(_(e_readonlysbx), use_gettext ? (char_u *)_(name) : name);
8012 	return TRUE;
8013     }
8014     return FALSE;
8015 }
8016 
8017 /*
8018  * Return TRUE if di_flags "flags" indicates variable "name" is fixed.
8019  * Also give an error message.
8020  */
8021     int
8022 var_check_fixed(int flags, char_u *name, int use_gettext)
8023 {
8024     if (flags & DI_FLAGS_FIX)
8025     {
8026 	semsg(_("E795: Cannot delete variable %s"),
8027 				      use_gettext ? (char_u *)_(name) : name);
8028 	return TRUE;
8029     }
8030     return FALSE;
8031 }
8032 
8033 /*
8034  * Check if a funcref is assigned to a valid variable name.
8035  * Return TRUE and give an error if not.
8036  */
8037     int
8038 var_check_func_name(
8039     char_u *name,    /* points to start of variable name */
8040     int    new_var)  /* TRUE when creating the variable */
8041 {
8042     /* Allow for w: b: s: and t:. */
8043     if (!(vim_strchr((char_u *)"wbst", name[0]) != NULL && name[1] == ':')
8044 	    && !ASCII_ISUPPER((name[0] != NUL && name[1] == ':')
8045 						     ? name[2] : name[0]))
8046     {
8047 	semsg(_("E704: Funcref variable name must start with a capital: %s"),
8048 									name);
8049 	return TRUE;
8050     }
8051     /* Don't allow hiding a function.  When "v" is not NULL we might be
8052      * assigning another function to the same var, the type is checked
8053      * below. */
8054     if (new_var && function_exists(name, FALSE))
8055     {
8056 	semsg(_("E705: Variable name conflicts with existing function: %s"),
8057 								    name);
8058 	return TRUE;
8059     }
8060     return FALSE;
8061 }
8062 
8063 /*
8064  * Return TRUE if "flags" indicates variable "name" is locked (immutable).
8065  * Also give an error message, using "name" or _("name") when use_gettext is
8066  * TRUE.
8067  */
8068     int
8069 var_check_lock(int lock, char_u *name, int use_gettext)
8070 {
8071     if (lock & VAR_LOCKED)
8072     {
8073 	semsg(_("E741: Value is locked: %s"),
8074 				name == NULL ? (char_u *)_("Unknown")
8075 					     : use_gettext ? (char_u *)_(name)
8076 					     : name);
8077 	return TRUE;
8078     }
8079     if (lock & VAR_FIXED)
8080     {
8081 	semsg(_("E742: Cannot change value of %s"),
8082 				name == NULL ? (char_u *)_("Unknown")
8083 					     : use_gettext ? (char_u *)_(name)
8084 					     : name);
8085 	return TRUE;
8086     }
8087     return FALSE;
8088 }
8089 
8090 /*
8091  * Return TRUE if typeval "tv" and its value are set to be locked (immutable).
8092  * Also give an error message, using "name" or _("name") when use_gettext is
8093  * TRUE.
8094  */
8095     static int
8096 tv_check_lock(typval_T *tv, char_u *name, int use_gettext)
8097 {
8098     int	lock = 0;
8099 
8100     switch (tv->v_type)
8101     {
8102 	case VAR_BLOB:
8103 	    if (tv->vval.v_blob != NULL)
8104 		lock = tv->vval.v_blob->bv_lock;
8105 	    break;
8106 	case VAR_LIST:
8107 	    if (tv->vval.v_list != NULL)
8108 		lock = tv->vval.v_list->lv_lock;
8109 	    break;
8110 	case VAR_DICT:
8111 	    if (tv->vval.v_dict != NULL)
8112 		lock = tv->vval.v_dict->dv_lock;
8113 	    break;
8114 	default:
8115 	    break;
8116     }
8117     return var_check_lock(tv->v_lock, name, use_gettext)
8118 		    || (lock != 0 && var_check_lock(lock, name, use_gettext));
8119 }
8120 
8121 /*
8122  * Check if a variable name is valid.
8123  * Return FALSE and give an error if not.
8124  */
8125     int
8126 valid_varname(char_u *varname)
8127 {
8128     char_u *p;
8129 
8130     for (p = varname; *p != NUL; ++p)
8131 	if (!eval_isnamec1(*p) && (p == varname || !VIM_ISDIGIT(*p))
8132 						   && *p != AUTOLOAD_CHAR)
8133 	{
8134 	    semsg(_(e_illvar), varname);
8135 	    return FALSE;
8136 	}
8137     return TRUE;
8138 }
8139 
8140 /*
8141  * Copy the values from typval_T "from" to typval_T "to".
8142  * When needed allocates string or increases reference count.
8143  * Does not make a copy of a list, blob or dict but copies the reference!
8144  * It is OK for "from" and "to" to point to the same item.  This is used to
8145  * make a copy later.
8146  */
8147     void
8148 copy_tv(typval_T *from, typval_T *to)
8149 {
8150     to->v_type = from->v_type;
8151     to->v_lock = 0;
8152     switch (from->v_type)
8153     {
8154 	case VAR_NUMBER:
8155 	case VAR_SPECIAL:
8156 	    to->vval.v_number = from->vval.v_number;
8157 	    break;
8158 	case VAR_FLOAT:
8159 #ifdef FEAT_FLOAT
8160 	    to->vval.v_float = from->vval.v_float;
8161 	    break;
8162 #endif
8163 	case VAR_JOB:
8164 #ifdef FEAT_JOB_CHANNEL
8165 	    to->vval.v_job = from->vval.v_job;
8166 	    if (to->vval.v_job != NULL)
8167 		++to->vval.v_job->jv_refcount;
8168 	    break;
8169 #endif
8170 	case VAR_CHANNEL:
8171 #ifdef FEAT_JOB_CHANNEL
8172 	    to->vval.v_channel = from->vval.v_channel;
8173 	    if (to->vval.v_channel != NULL)
8174 		++to->vval.v_channel->ch_refcount;
8175 	    break;
8176 #endif
8177 	case VAR_STRING:
8178 	case VAR_FUNC:
8179 	    if (from->vval.v_string == NULL)
8180 		to->vval.v_string = NULL;
8181 	    else
8182 	    {
8183 		to->vval.v_string = vim_strsave(from->vval.v_string);
8184 		if (from->v_type == VAR_FUNC)
8185 		    func_ref(to->vval.v_string);
8186 	    }
8187 	    break;
8188 	case VAR_PARTIAL:
8189 	    if (from->vval.v_partial == NULL)
8190 		to->vval.v_partial = NULL;
8191 	    else
8192 	    {
8193 		to->vval.v_partial = from->vval.v_partial;
8194 		++to->vval.v_partial->pt_refcount;
8195 	    }
8196 	    break;
8197 	case VAR_BLOB:
8198 	    if (from->vval.v_blob == NULL)
8199 		to->vval.v_blob = NULL;
8200 	    else
8201 	    {
8202 		to->vval.v_blob = from->vval.v_blob;
8203 		++to->vval.v_blob->bv_refcount;
8204 	    }
8205 	    break;
8206 	case VAR_LIST:
8207 	    if (from->vval.v_list == NULL)
8208 		to->vval.v_list = NULL;
8209 	    else
8210 	    {
8211 		to->vval.v_list = from->vval.v_list;
8212 		++to->vval.v_list->lv_refcount;
8213 	    }
8214 	    break;
8215 	case VAR_DICT:
8216 	    if (from->vval.v_dict == NULL)
8217 		to->vval.v_dict = NULL;
8218 	    else
8219 	    {
8220 		to->vval.v_dict = from->vval.v_dict;
8221 		++to->vval.v_dict->dv_refcount;
8222 	    }
8223 	    break;
8224 	case VAR_UNKNOWN:
8225 	    internal_error("copy_tv(UNKNOWN)");
8226 	    break;
8227     }
8228 }
8229 
8230 /*
8231  * Make a copy of an item.
8232  * Lists and Dictionaries are also copied.  A deep copy if "deep" is set.
8233  * For deepcopy() "copyID" is zero for a full copy or the ID for when a
8234  * reference to an already copied list/dict can be used.
8235  * Returns FAIL or OK.
8236  */
8237     int
8238 item_copy(
8239     typval_T	*from,
8240     typval_T	*to,
8241     int		deep,
8242     int		copyID)
8243 {
8244     static int	recurse = 0;
8245     int		ret = OK;
8246 
8247     if (recurse >= DICT_MAXNEST)
8248     {
8249 	emsg(_("E698: variable nested too deep for making a copy"));
8250 	return FAIL;
8251     }
8252     ++recurse;
8253 
8254     switch (from->v_type)
8255     {
8256 	case VAR_NUMBER:
8257 	case VAR_FLOAT:
8258 	case VAR_STRING:
8259 	case VAR_FUNC:
8260 	case VAR_PARTIAL:
8261 	case VAR_SPECIAL:
8262 	case VAR_JOB:
8263 	case VAR_CHANNEL:
8264 	    copy_tv(from, to);
8265 	    break;
8266 	case VAR_LIST:
8267 	    to->v_type = VAR_LIST;
8268 	    to->v_lock = 0;
8269 	    if (from->vval.v_list == NULL)
8270 		to->vval.v_list = NULL;
8271 	    else if (copyID != 0 && from->vval.v_list->lv_copyID == copyID)
8272 	    {
8273 		/* use the copy made earlier */
8274 		to->vval.v_list = from->vval.v_list->lv_copylist;
8275 		++to->vval.v_list->lv_refcount;
8276 	    }
8277 	    else
8278 		to->vval.v_list = list_copy(from->vval.v_list, deep, copyID);
8279 	    if (to->vval.v_list == NULL)
8280 		ret = FAIL;
8281 	    break;
8282 	case VAR_BLOB:
8283 	    ret = blob_copy(from, to);
8284 	    break;
8285 	case VAR_DICT:
8286 	    to->v_type = VAR_DICT;
8287 	    to->v_lock = 0;
8288 	    if (from->vval.v_dict == NULL)
8289 		to->vval.v_dict = NULL;
8290 	    else if (copyID != 0 && from->vval.v_dict->dv_copyID == copyID)
8291 	    {
8292 		/* use the copy made earlier */
8293 		to->vval.v_dict = from->vval.v_dict->dv_copydict;
8294 		++to->vval.v_dict->dv_refcount;
8295 	    }
8296 	    else
8297 		to->vval.v_dict = dict_copy(from->vval.v_dict, deep, copyID);
8298 	    if (to->vval.v_dict == NULL)
8299 		ret = FAIL;
8300 	    break;
8301 	case VAR_UNKNOWN:
8302 	    internal_error("item_copy(UNKNOWN)");
8303 	    ret = FAIL;
8304     }
8305     --recurse;
8306     return ret;
8307 }
8308 
8309 /*
8310  * This function is used by f_input() and f_inputdialog() functions. The third
8311  * argument to f_input() specifies the type of completion to use at the
8312  * prompt. The third argument to f_inputdialog() specifies the value to return
8313  * when the user cancels the prompt.
8314  */
8315     void
8316 get_user_input(
8317     typval_T	*argvars,
8318     typval_T	*rettv,
8319     int		inputdialog,
8320     int		secret)
8321 {
8322     char_u	*prompt = tv_get_string_chk(&argvars[0]);
8323     char_u	*p = NULL;
8324     int		c;
8325     char_u	buf[NUMBUFLEN];
8326     int		cmd_silent_save = cmd_silent;
8327     char_u	*defstr = (char_u *)"";
8328     int		xp_type = EXPAND_NOTHING;
8329     char_u	*xp_arg = NULL;
8330 
8331     rettv->v_type = VAR_STRING;
8332     rettv->vval.v_string = NULL;
8333 
8334 #ifdef NO_CONSOLE_INPUT
8335     /* While starting up, there is no place to enter text. When running tests
8336      * with --not-a-term we assume feedkeys() will be used. */
8337     if (no_console_input() && !is_not_a_term())
8338 	return;
8339 #endif
8340 
8341     cmd_silent = FALSE;		/* Want to see the prompt. */
8342     if (prompt != NULL)
8343     {
8344 	/* Only the part of the message after the last NL is considered as
8345 	 * prompt for the command line */
8346 	p = vim_strrchr(prompt, '\n');
8347 	if (p == NULL)
8348 	    p = prompt;
8349 	else
8350 	{
8351 	    ++p;
8352 	    c = *p;
8353 	    *p = NUL;
8354 	    msg_start();
8355 	    msg_clr_eos();
8356 	    msg_puts_attr((char *)prompt, echo_attr);
8357 	    msg_didout = FALSE;
8358 	    msg_starthere();
8359 	    *p = c;
8360 	}
8361 	cmdline_row = msg_row;
8362 
8363 	if (argvars[1].v_type != VAR_UNKNOWN)
8364 	{
8365 	    defstr = tv_get_string_buf_chk(&argvars[1], buf);
8366 	    if (defstr != NULL)
8367 		stuffReadbuffSpec(defstr);
8368 
8369 	    if (!inputdialog && argvars[2].v_type != VAR_UNKNOWN)
8370 	    {
8371 		char_u	*xp_name;
8372 		int	xp_namelen;
8373 		long	argt;
8374 
8375 		/* input() with a third argument: completion */
8376 		rettv->vval.v_string = NULL;
8377 
8378 		xp_name = tv_get_string_buf_chk(&argvars[2], buf);
8379 		if (xp_name == NULL)
8380 		    return;
8381 
8382 		xp_namelen = (int)STRLEN(xp_name);
8383 
8384 		if (parse_compl_arg(xp_name, xp_namelen, &xp_type, &argt,
8385 							     &xp_arg) == FAIL)
8386 		    return;
8387 	    }
8388 	}
8389 
8390 	if (defstr != NULL)
8391 	{
8392 	    int save_ex_normal_busy = ex_normal_busy;
8393 
8394 	    ex_normal_busy = 0;
8395 	    rettv->vval.v_string =
8396 		getcmdline_prompt(secret ? NUL : '@', p, echo_attr,
8397 							      xp_type, xp_arg);
8398 	    ex_normal_busy = save_ex_normal_busy;
8399 	}
8400 	if (inputdialog && rettv->vval.v_string == NULL
8401 		&& argvars[1].v_type != VAR_UNKNOWN
8402 		&& argvars[2].v_type != VAR_UNKNOWN)
8403 	    rettv->vval.v_string = vim_strsave(tv_get_string_buf(
8404 							   &argvars[2], buf));
8405 
8406 	vim_free(xp_arg);
8407 
8408 	/* since the user typed this, no need to wait for return */
8409 	need_wait_return = FALSE;
8410 	msg_didout = FALSE;
8411     }
8412     cmd_silent = cmd_silent_save;
8413 }
8414 
8415 /*
8416  * ":echo expr1 ..."	print each argument separated with a space, add a
8417  *			newline at the end.
8418  * ":echon expr1 ..."	print each argument plain.
8419  */
8420     void
8421 ex_echo(exarg_T *eap)
8422 {
8423     char_u	*arg = eap->arg;
8424     typval_T	rettv;
8425     char_u	*tofree;
8426     char_u	*p;
8427     int		needclr = TRUE;
8428     int		atstart = TRUE;
8429     char_u	numbuf[NUMBUFLEN];
8430     int		did_emsg_before = did_emsg;
8431     int		called_emsg_before = called_emsg;
8432 
8433     if (eap->skip)
8434 	++emsg_skip;
8435     while (*arg != NUL && *arg != '|' && *arg != '\n' && !got_int)
8436     {
8437 	/* If eval1() causes an error message the text from the command may
8438 	 * still need to be cleared. E.g., "echo 22,44". */
8439 	need_clr_eos = needclr;
8440 
8441 	p = arg;
8442 	if (eval1(&arg, &rettv, !eap->skip) == FAIL)
8443 	{
8444 	    /*
8445 	     * Report the invalid expression unless the expression evaluation
8446 	     * has been cancelled due to an aborting error, an interrupt, or an
8447 	     * exception.
8448 	     */
8449 	    if (!aborting() && did_emsg == did_emsg_before
8450 					  && called_emsg == called_emsg_before)
8451 		semsg(_(e_invexpr2), p);
8452 	    need_clr_eos = FALSE;
8453 	    break;
8454 	}
8455 	need_clr_eos = FALSE;
8456 
8457 	if (!eap->skip)
8458 	{
8459 	    if (atstart)
8460 	    {
8461 		atstart = FALSE;
8462 		/* Call msg_start() after eval1(), evaluating the expression
8463 		 * may cause a message to appear. */
8464 		if (eap->cmdidx == CMD_echo)
8465 		{
8466 		    /* Mark the saved text as finishing the line, so that what
8467 		     * follows is displayed on a new line when scrolling back
8468 		     * at the more prompt. */
8469 		    msg_sb_eol();
8470 		    msg_start();
8471 		}
8472 	    }
8473 	    else if (eap->cmdidx == CMD_echo)
8474 		msg_puts_attr(" ", echo_attr);
8475 	    p = echo_string(&rettv, &tofree, numbuf, get_copyID());
8476 	    if (p != NULL)
8477 		for ( ; *p != NUL && !got_int; ++p)
8478 		{
8479 		    if (*p == '\n' || *p == '\r' || *p == TAB)
8480 		    {
8481 			if (*p != TAB && needclr)
8482 			{
8483 			    /* remove any text still there from the command */
8484 			    msg_clr_eos();
8485 			    needclr = FALSE;
8486 			}
8487 			msg_putchar_attr(*p, echo_attr);
8488 		    }
8489 		    else
8490 		    {
8491 			if (has_mbyte)
8492 			{
8493 			    int i = (*mb_ptr2len)(p);
8494 
8495 			    (void)msg_outtrans_len_attr(p, i, echo_attr);
8496 			    p += i - 1;
8497 			}
8498 			else
8499 			    (void)msg_outtrans_len_attr(p, 1, echo_attr);
8500 		    }
8501 		}
8502 	    vim_free(tofree);
8503 	}
8504 	clear_tv(&rettv);
8505 	arg = skipwhite(arg);
8506     }
8507     eap->nextcmd = check_nextcmd(arg);
8508 
8509     if (eap->skip)
8510 	--emsg_skip;
8511     else
8512     {
8513 	/* remove text that may still be there from the command */
8514 	if (needclr)
8515 	    msg_clr_eos();
8516 	if (eap->cmdidx == CMD_echo)
8517 	    msg_end();
8518     }
8519 }
8520 
8521 /*
8522  * ":echohl {name}".
8523  */
8524     void
8525 ex_echohl(exarg_T *eap)
8526 {
8527     echo_attr = syn_name2attr(eap->arg);
8528 }
8529 
8530 /*
8531  * ":execute expr1 ..."	execute the result of an expression.
8532  * ":echomsg expr1 ..."	Print a message
8533  * ":echoerr expr1 ..."	Print an error
8534  * Each gets spaces around each argument and a newline at the end for
8535  * echo commands
8536  */
8537     void
8538 ex_execute(exarg_T *eap)
8539 {
8540     char_u	*arg = eap->arg;
8541     typval_T	rettv;
8542     int		ret = OK;
8543     char_u	*p;
8544     garray_T	ga;
8545     int		len;
8546     int		save_did_emsg = did_emsg;
8547 
8548     ga_init2(&ga, 1, 80);
8549 
8550     if (eap->skip)
8551 	++emsg_skip;
8552     while (*arg != NUL && *arg != '|' && *arg != '\n')
8553     {
8554 	p = arg;
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 /* reset v:option_new, v:option_old and v:option_type */
9223     void
9224 reset_v_option_vars(void)
9225 {
9226     set_vim_var_string(VV_OPTION_NEW,  NULL, -1);
9227     set_vim_var_string(VV_OPTION_OLD,  NULL, -1);
9228     set_vim_var_string(VV_OPTION_TYPE, NULL, -1);
9229 }
9230 
9231 /*
9232  * Prepare "gap" for an assert error and add the sourcing position.
9233  */
9234     void
9235 prepare_assert_error(garray_T *gap)
9236 {
9237     char buf[NUMBUFLEN];
9238 
9239     ga_init2(gap, 1, 100);
9240     if (sourcing_name != NULL)
9241     {
9242 	ga_concat(gap, sourcing_name);
9243 	if (sourcing_lnum > 0)
9244 	    ga_concat(gap, (char_u *)" ");
9245     }
9246     if (sourcing_lnum > 0)
9247     {
9248 	sprintf(buf, "line %ld", (long)sourcing_lnum);
9249 	ga_concat(gap, (char_u *)buf);
9250     }
9251     if (sourcing_name != NULL || sourcing_lnum > 0)
9252 	ga_concat(gap, (char_u *)": ");
9253 }
9254 
9255 /*
9256  * Add an assert error to v:errors.
9257  */
9258     void
9259 assert_error(garray_T *gap)
9260 {
9261     struct vimvar   *vp = &vimvars[VV_ERRORS];
9262 
9263     if (vp->vv_type != VAR_LIST || vimvars[VV_ERRORS].vv_list == NULL)
9264 	/* Make sure v:errors is a list. */
9265 	set_vim_var_list(VV_ERRORS, list_alloc());
9266     list_append_string(vimvars[VV_ERRORS].vv_list, gap->ga_data, gap->ga_len);
9267 }
9268 
9269     int
9270 assert_equal_common(typval_T *argvars, assert_type_T atype)
9271 {
9272     garray_T	ga;
9273 
9274     if (tv_equal(&argvars[0], &argvars[1], FALSE, FALSE)
9275 						   != (atype == ASSERT_EQUAL))
9276     {
9277 	prepare_assert_error(&ga);
9278 	fill_assert_error(&ga, &argvars[2], NULL, &argvars[0], &argvars[1],
9279 								       atype);
9280 	assert_error(&ga);
9281 	ga_clear(&ga);
9282 	return 1;
9283     }
9284     return 0;
9285 }
9286 
9287     int
9288 assert_equalfile(typval_T *argvars)
9289 {
9290     char_u	buf1[NUMBUFLEN];
9291     char_u	buf2[NUMBUFLEN];
9292     char_u	*fname1 = tv_get_string_buf_chk(&argvars[0], buf1);
9293     char_u	*fname2 = tv_get_string_buf_chk(&argvars[1], buf2);
9294     garray_T	ga;
9295     FILE	*fd1;
9296     FILE	*fd2;
9297 
9298     if (fname1 == NULL || fname2 == NULL)
9299 	return 0;
9300 
9301     IObuff[0] = NUL;
9302     fd1 = mch_fopen((char *)fname1, READBIN);
9303     if (fd1 == NULL)
9304     {
9305 	vim_snprintf((char *)IObuff, IOSIZE, (char *)e_notread, fname1);
9306     }
9307     else
9308     {
9309 	fd2 = mch_fopen((char *)fname2, READBIN);
9310 	if (fd2 == NULL)
9311 	{
9312 	    fclose(fd1);
9313 	    vim_snprintf((char *)IObuff, IOSIZE, (char *)e_notread, fname2);
9314 	}
9315 	else
9316 	{
9317 	    int c1, c2;
9318 	    long count = 0;
9319 
9320 	    for (;;)
9321 	    {
9322 		c1 = fgetc(fd1);
9323 		c2 = fgetc(fd2);
9324 		if (c1 == EOF)
9325 		{
9326 		    if (c2 != EOF)
9327 			STRCPY(IObuff, "first file is shorter");
9328 		    break;
9329 		}
9330 		else if (c2 == EOF)
9331 		{
9332 		    STRCPY(IObuff, "second file is shorter");
9333 		    break;
9334 		}
9335 		else if (c1 != c2)
9336 		{
9337 		    vim_snprintf((char *)IObuff, IOSIZE,
9338 					      "difference at byte %ld", count);
9339 		    break;
9340 		}
9341 		++count;
9342 	    }
9343 	    fclose(fd1);
9344 	    fclose(fd2);
9345 	}
9346     }
9347     if (IObuff[0] != NUL)
9348     {
9349 	prepare_assert_error(&ga);
9350 	ga_concat(&ga, IObuff);
9351 	assert_error(&ga);
9352 	ga_clear(&ga);
9353 	return 1;
9354     }
9355     return 0;
9356 }
9357 
9358     int
9359 assert_match_common(typval_T *argvars, assert_type_T atype)
9360 {
9361     garray_T	ga;
9362     char_u	buf1[NUMBUFLEN];
9363     char_u	buf2[NUMBUFLEN];
9364     char_u	*pat = tv_get_string_buf_chk(&argvars[0], buf1);
9365     char_u	*text = tv_get_string_buf_chk(&argvars[1], buf2);
9366 
9367     if (pat == NULL || text == NULL)
9368 	emsg(_(e_invarg));
9369     else if (pattern_match(pat, text, FALSE) != (atype == ASSERT_MATCH))
9370     {
9371 	prepare_assert_error(&ga);
9372 	fill_assert_error(&ga, &argvars[2], NULL, &argvars[0], &argvars[1],
9373 									atype);
9374 	assert_error(&ga);
9375 	ga_clear(&ga);
9376 	return 1;
9377     }
9378     return 0;
9379 }
9380 
9381     int
9382 assert_inrange(typval_T *argvars)
9383 {
9384     garray_T	ga;
9385     int		error = FALSE;
9386     char_u	*tofree;
9387     char	msg[200];
9388     char_u	numbuf[NUMBUFLEN];
9389 
9390 #ifdef FEAT_FLOAT
9391     if (argvars[0].v_type == VAR_FLOAT
9392 	    || argvars[1].v_type == VAR_FLOAT
9393 	    || argvars[2].v_type == VAR_FLOAT)
9394     {
9395 	float_T flower = tv_get_float(&argvars[0]);
9396 	float_T fupper = tv_get_float(&argvars[1]);
9397 	float_T factual = tv_get_float(&argvars[2]);
9398 
9399 	if (factual < flower || factual > fupper)
9400 	{
9401 	    prepare_assert_error(&ga);
9402 	    if (argvars[3].v_type != VAR_UNKNOWN)
9403 	    {
9404 		ga_concat(&ga, tv2string(&argvars[3], &tofree, numbuf, 0));
9405 		vim_free(tofree);
9406 	    }
9407 	    else
9408 	    {
9409 		vim_snprintf(msg, 200, "Expected range %g - %g, but got %g",
9410 						      flower, fupper, factual);
9411 		ga_concat(&ga, (char_u *)msg);
9412 	    }
9413 	    assert_error(&ga);
9414 	    ga_clear(&ga);
9415 	    return 1;
9416 	}
9417     }
9418     else
9419 #endif
9420     {
9421 	varnumber_T	lower = tv_get_number_chk(&argvars[0], &error);
9422 	varnumber_T	upper = tv_get_number_chk(&argvars[1], &error);
9423 	varnumber_T	actual = tv_get_number_chk(&argvars[2], &error);
9424 
9425 	if (error)
9426 	    return 0;
9427 	if (actual < lower || actual > upper)
9428 	{
9429 	    prepare_assert_error(&ga);
9430 	    if (argvars[3].v_type != VAR_UNKNOWN)
9431 	    {
9432 		ga_concat(&ga, tv2string(&argvars[3], &tofree, numbuf, 0));
9433 		vim_free(tofree);
9434 	    }
9435 	    else
9436 	    {
9437 		vim_snprintf(msg, 200, "Expected range %ld - %ld, but got %ld",
9438 				       (long)lower, (long)upper, (long)actual);
9439 		ga_concat(&ga, (char_u *)msg);
9440 	    }
9441 	    assert_error(&ga);
9442 	    ga_clear(&ga);
9443 	    return 1;
9444 	}
9445     }
9446     return 0;
9447 }
9448 
9449 /*
9450  * Common for assert_true() and assert_false().
9451  * Return non-zero for failure.
9452  */
9453     int
9454 assert_bool(typval_T *argvars, int isTrue)
9455 {
9456     int		error = FALSE;
9457     garray_T	ga;
9458 
9459     if (argvars[0].v_type == VAR_SPECIAL
9460 	    && argvars[0].vval.v_number == (isTrue ? VVAL_TRUE : VVAL_FALSE))
9461 	return 0;
9462     if (argvars[0].v_type != VAR_NUMBER
9463 	    || (tv_get_number_chk(&argvars[0], &error) == 0) == isTrue
9464 	    || error)
9465     {
9466 	prepare_assert_error(&ga);
9467 	fill_assert_error(&ga, &argvars[1],
9468 		(char_u *)(isTrue ? "True" : "False"),
9469 		NULL, &argvars[0], ASSERT_OTHER);
9470 	assert_error(&ga);
9471 	ga_clear(&ga);
9472 	return 1;
9473     }
9474     return 0;
9475 }
9476 
9477     int
9478 assert_report(typval_T *argvars)
9479 {
9480     garray_T	ga;
9481 
9482     prepare_assert_error(&ga);
9483     ga_concat(&ga, tv_get_string(&argvars[0]));
9484     assert_error(&ga);
9485     ga_clear(&ga);
9486     return 1;
9487 }
9488 
9489     int
9490 assert_exception(typval_T *argvars)
9491 {
9492     garray_T	ga;
9493     char_u	*error = tv_get_string_chk(&argvars[0]);
9494 
9495     if (vimvars[VV_EXCEPTION].vv_str == NULL)
9496     {
9497 	prepare_assert_error(&ga);
9498 	ga_concat(&ga, (char_u *)"v:exception is not set");
9499 	assert_error(&ga);
9500 	ga_clear(&ga);
9501 	return 1;
9502     }
9503     else if (error != NULL
9504 	&& strstr((char *)vimvars[VV_EXCEPTION].vv_str, (char *)error) == NULL)
9505     {
9506 	prepare_assert_error(&ga);
9507 	fill_assert_error(&ga, &argvars[1], NULL, &argvars[0],
9508 				  &vimvars[VV_EXCEPTION].vv_tv, ASSERT_OTHER);
9509 	assert_error(&ga);
9510 	ga_clear(&ga);
9511 	return 1;
9512     }
9513     return 0;
9514 }
9515 
9516     int
9517 assert_beeps(typval_T *argvars)
9518 {
9519     char_u	*cmd = tv_get_string_chk(&argvars[0]);
9520     garray_T	ga;
9521     int		ret = 0;
9522 
9523     called_vim_beep = FALSE;
9524     suppress_errthrow = TRUE;
9525     emsg_silent = FALSE;
9526     do_cmdline_cmd(cmd);
9527     if (!called_vim_beep)
9528     {
9529 	prepare_assert_error(&ga);
9530 	ga_concat(&ga, (char_u *)"command did not beep: ");
9531 	ga_concat(&ga, cmd);
9532 	assert_error(&ga);
9533 	ga_clear(&ga);
9534 	ret = 1;
9535     }
9536 
9537     suppress_errthrow = FALSE;
9538     emsg_on_display = FALSE;
9539     return ret;
9540 }
9541 
9542     int
9543 assert_fails(typval_T *argvars)
9544 {
9545     char_u	*cmd = tv_get_string_chk(&argvars[0]);
9546     garray_T	ga;
9547     int		ret = 0;
9548     char_u	numbuf[NUMBUFLEN];
9549     char_u	*tofree;
9550 
9551     called_emsg = FALSE;
9552     suppress_errthrow = TRUE;
9553     emsg_silent = TRUE;
9554     do_cmdline_cmd(cmd);
9555     if (!called_emsg)
9556     {
9557 	prepare_assert_error(&ga);
9558 	ga_concat(&ga, (char_u *)"command did not fail: ");
9559 	if (argvars[1].v_type != VAR_UNKNOWN
9560 					   && argvars[2].v_type != VAR_UNKNOWN)
9561 	{
9562 	    ga_concat(&ga, echo_string(&argvars[2], &tofree, numbuf, 0));
9563 	    vim_free(tofree);
9564 	}
9565 	else
9566 	    ga_concat(&ga, cmd);
9567 	assert_error(&ga);
9568 	ga_clear(&ga);
9569 	ret = 1;
9570     }
9571     else if (argvars[1].v_type != VAR_UNKNOWN)
9572     {
9573 	char_u	buf[NUMBUFLEN];
9574 	char	*error = (char *)tv_get_string_buf_chk(&argvars[1], buf);
9575 
9576 	if (error == NULL
9577 		  || strstr((char *)vimvars[VV_ERRMSG].vv_str, error) == NULL)
9578 	{
9579 	    prepare_assert_error(&ga);
9580 	    fill_assert_error(&ga, &argvars[2], NULL, &argvars[1],
9581 				     &vimvars[VV_ERRMSG].vv_tv, ASSERT_OTHER);
9582 	    assert_error(&ga);
9583 	    ga_clear(&ga);
9584 	ret = 1;
9585 	}
9586     }
9587 
9588     called_emsg = FALSE;
9589     suppress_errthrow = FALSE;
9590     emsg_silent = FALSE;
9591     emsg_on_display = FALSE;
9592     set_vim_var_string(VV_ERRMSG, NULL, 0);
9593     return ret;
9594 }
9595 
9596 /*
9597  * Append "p[clen]" to "gap", escaping unprintable characters.
9598  * Changes NL to \n, CR to \r, etc.
9599  */
9600     static void
9601 ga_concat_esc(garray_T *gap, char_u *p, int clen)
9602 {
9603     char_u  buf[NUMBUFLEN];
9604 
9605     if (clen > 1)
9606     {
9607 	mch_memmove(buf, p, clen);
9608 	buf[clen] = NUL;
9609 	ga_concat(gap, buf);
9610     }
9611     else switch (*p)
9612     {
9613 	case BS: ga_concat(gap, (char_u *)"\\b"); break;
9614 	case ESC: ga_concat(gap, (char_u *)"\\e"); break;
9615 	case FF: ga_concat(gap, (char_u *)"\\f"); break;
9616 	case NL: ga_concat(gap, (char_u *)"\\n"); break;
9617 	case TAB: ga_concat(gap, (char_u *)"\\t"); break;
9618 	case CAR: ga_concat(gap, (char_u *)"\\r"); break;
9619 	case '\\': ga_concat(gap, (char_u *)"\\\\"); break;
9620 	default:
9621 		   if (*p < ' ')
9622 		   {
9623 		       vim_snprintf((char *)buf, NUMBUFLEN, "\\x%02x", *p);
9624 		       ga_concat(gap, buf);
9625 		   }
9626 		   else
9627 		       ga_append(gap, *p);
9628 		   break;
9629     }
9630 }
9631 
9632 /*
9633  * Append "str" to "gap", escaping unprintable characters.
9634  * Changes NL to \n, CR to \r, etc.
9635  */
9636     static void
9637 ga_concat_shorten_esc(garray_T *gap, char_u *str)
9638 {
9639     char_u  *p;
9640     char_u  *s;
9641     int	    c;
9642     int	    clen;
9643     char_u  buf[NUMBUFLEN];
9644     int	    same_len;
9645 
9646     if (str == NULL)
9647     {
9648 	ga_concat(gap, (char_u *)"NULL");
9649 	return;
9650     }
9651 
9652     for (p = str; *p != NUL; ++p)
9653     {
9654 	same_len = 1;
9655 	s = p;
9656 	c = mb_ptr2char_adv(&s);
9657 	clen = s - p;
9658 	while (*s != NUL && c == mb_ptr2char(s))
9659 	{
9660 	    ++same_len;
9661 	    s += clen;
9662 	}
9663 	if (same_len > 20)
9664 	{
9665 	    ga_concat(gap, (char_u *)"\\[");
9666 	    ga_concat_esc(gap, p, clen);
9667 	    ga_concat(gap, (char_u *)" occurs ");
9668 	    vim_snprintf((char *)buf, NUMBUFLEN, "%d", same_len);
9669 	    ga_concat(gap, buf);
9670 	    ga_concat(gap, (char_u *)" times]");
9671 	    p = s - 1;
9672 	}
9673 	else
9674 	    ga_concat_esc(gap, p, clen);
9675     }
9676 }
9677 
9678 /*
9679  * Fill "gap" with information about an assert error.
9680  */
9681     void
9682 fill_assert_error(
9683     garray_T	*gap,
9684     typval_T	*opt_msg_tv,
9685     char_u      *exp_str,
9686     typval_T	*exp_tv,
9687     typval_T	*got_tv,
9688     assert_type_T atype)
9689 {
9690     char_u	numbuf[NUMBUFLEN];
9691     char_u	*tofree;
9692 
9693     if (opt_msg_tv->v_type != VAR_UNKNOWN)
9694     {
9695 	ga_concat(gap, echo_string(opt_msg_tv, &tofree, numbuf, 0));
9696 	vim_free(tofree);
9697 	ga_concat(gap, (char_u *)": ");
9698     }
9699 
9700     if (atype == ASSERT_MATCH || atype == ASSERT_NOTMATCH)
9701 	ga_concat(gap, (char_u *)"Pattern ");
9702     else if (atype == ASSERT_NOTEQUAL)
9703 	ga_concat(gap, (char_u *)"Expected not equal to ");
9704     else
9705 	ga_concat(gap, (char_u *)"Expected ");
9706     if (exp_str == NULL)
9707     {
9708 	ga_concat_shorten_esc(gap, tv2string(exp_tv, &tofree, numbuf, 0));
9709 	vim_free(tofree);
9710     }
9711     else
9712 	ga_concat_shorten_esc(gap, exp_str);
9713     if (atype != ASSERT_NOTEQUAL)
9714     {
9715 	if (atype == ASSERT_MATCH)
9716 	    ga_concat(gap, (char_u *)" does not match ");
9717 	else if (atype == ASSERT_NOTMATCH)
9718 	    ga_concat(gap, (char_u *)" does match ");
9719 	else
9720 	    ga_concat(gap, (char_u *)" but got ");
9721 	ga_concat_shorten_esc(gap, tv2string(got_tv, &tofree, numbuf, 0));
9722 	vim_free(tofree);
9723     }
9724 }
9725 
9726 /*
9727  * Compare "typ1" and "typ2".  Put the result in "typ1".
9728  */
9729     int
9730 typval_compare(
9731     typval_T	*typ1,   /* first operand */
9732     typval_T	*typ2,   /* second operand */
9733     exptype_T	type,    /* operator */
9734     int		type_is, /* TRUE for "is" and "isnot" */
9735     int		ic)      /* ignore case */
9736 {
9737     int		i;
9738     varnumber_T	n1, n2;
9739     char_u	*s1, *s2;
9740     char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
9741 
9742     if (type_is && typ1->v_type != typ2->v_type)
9743     {
9744 	/* For "is" a different type always means FALSE, for "notis"
9745 	    * it means TRUE. */
9746 	n1 = (type == TYPE_NEQUAL);
9747     }
9748     else if (typ1->v_type == VAR_BLOB || typ2->v_type == VAR_BLOB)
9749     {
9750 	if (type_is)
9751 	{
9752 	    n1 = (typ1->v_type == typ2->v_type
9753 			    && typ1->vval.v_blob == typ2->vval.v_blob);
9754 	    if (type == TYPE_NEQUAL)
9755 		n1 = !n1;
9756 	}
9757 	else if (typ1->v_type != typ2->v_type
9758 		|| (type != TYPE_EQUAL && type != TYPE_NEQUAL))
9759 	{
9760 	    if (typ1->v_type != typ2->v_type)
9761 		emsg(_("E977: Can only compare Blob with Blob"));
9762 	    else
9763 		emsg(_(e_invalblob));
9764 	    clear_tv(typ1);
9765 	    return FAIL;
9766 	}
9767 	else
9768 	{
9769 	    // Compare two Blobs for being equal or unequal.
9770 	    n1 = blob_equal(typ1->vval.v_blob, typ2->vval.v_blob);
9771 	    if (type == TYPE_NEQUAL)
9772 		n1 = !n1;
9773 	}
9774     }
9775     else if (typ1->v_type == VAR_LIST || typ2->v_type == VAR_LIST)
9776     {
9777 	if (type_is)
9778 	{
9779 	    n1 = (typ1->v_type == typ2->v_type
9780 			    && typ1->vval.v_list == typ2->vval.v_list);
9781 	    if (type == TYPE_NEQUAL)
9782 		n1 = !n1;
9783 	}
9784 	else if (typ1->v_type != typ2->v_type
9785 		|| (type != TYPE_EQUAL && type != TYPE_NEQUAL))
9786 	{
9787 	    if (typ1->v_type != typ2->v_type)
9788 		emsg(_("E691: Can only compare List with List"));
9789 	    else
9790 		emsg(_("E692: Invalid operation for List"));
9791 	    clear_tv(typ1);
9792 	    return FAIL;
9793 	}
9794 	else
9795 	{
9796 	    /* Compare two Lists for being equal or unequal. */
9797 	    n1 = list_equal(typ1->vval.v_list, typ2->vval.v_list,
9798 							    ic, FALSE);
9799 	    if (type == TYPE_NEQUAL)
9800 		n1 = !n1;
9801 	}
9802     }
9803 
9804     else if (typ1->v_type == VAR_DICT || typ2->v_type == VAR_DICT)
9805     {
9806 	if (type_is)
9807 	{
9808 	    n1 = (typ1->v_type == typ2->v_type
9809 			    && typ1->vval.v_dict == typ2->vval.v_dict);
9810 	    if (type == TYPE_NEQUAL)
9811 		n1 = !n1;
9812 	}
9813 	else if (typ1->v_type != typ2->v_type
9814 		|| (type != TYPE_EQUAL && type != TYPE_NEQUAL))
9815 	{
9816 	    if (typ1->v_type != typ2->v_type)
9817 		emsg(_("E735: Can only compare Dictionary with Dictionary"));
9818 	    else
9819 		emsg(_("E736: Invalid operation for Dictionary"));
9820 	    clear_tv(typ1);
9821 	    return FAIL;
9822 	}
9823 	else
9824 	{
9825 	    /* Compare two Dictionaries for being equal or unequal. */
9826 	    n1 = dict_equal(typ1->vval.v_dict, typ2->vval.v_dict,
9827 							    ic, FALSE);
9828 	    if (type == TYPE_NEQUAL)
9829 		n1 = !n1;
9830 	}
9831     }
9832 
9833     else if (typ1->v_type == VAR_FUNC || typ2->v_type == VAR_FUNC
9834 	|| typ1->v_type == VAR_PARTIAL || typ2->v_type == VAR_PARTIAL)
9835     {
9836 	if (type != TYPE_EQUAL && type != TYPE_NEQUAL)
9837 	{
9838 	    emsg(_("E694: Invalid operation for Funcrefs"));
9839 	    clear_tv(typ1);
9840 	    return FAIL;
9841 	}
9842 	if ((typ1->v_type == VAR_PARTIAL
9843 					&& typ1->vval.v_partial == NULL)
9844 		|| (typ2->v_type == VAR_PARTIAL
9845 					&& typ2->vval.v_partial == NULL))
9846 	    /* when a partial is NULL assume not equal */
9847 	    n1 = FALSE;
9848 	else if (type_is)
9849 	{
9850 	    if (typ1->v_type == VAR_FUNC && typ2->v_type == VAR_FUNC)
9851 		/* strings are considered the same if their value is
9852 		    * the same */
9853 		n1 = tv_equal(typ1, typ2, ic, FALSE);
9854 	    else if (typ1->v_type == VAR_PARTIAL
9855 					&& typ2->v_type == VAR_PARTIAL)
9856 		n1 = (typ1->vval.v_partial == typ2->vval.v_partial);
9857 	    else
9858 		n1 = FALSE;
9859 	}
9860 	else
9861 	    n1 = tv_equal(typ1, typ2, ic, FALSE);
9862 	if (type == TYPE_NEQUAL)
9863 	    n1 = !n1;
9864     }
9865 
9866 #ifdef FEAT_FLOAT
9867     /*
9868 	* If one of the two variables is a float, compare as a float.
9869 	* When using "=~" or "!~", always compare as string.
9870 	*/
9871     else if ((typ1->v_type == VAR_FLOAT || typ2->v_type == VAR_FLOAT)
9872 	    && type != TYPE_MATCH && type != TYPE_NOMATCH)
9873     {
9874 	float_T f1, f2;
9875 
9876 	f1 = tv_get_float(typ1);
9877 	f2 = tv_get_float(typ2);
9878 	n1 = FALSE;
9879 	switch (type)
9880 	{
9881 	    case TYPE_EQUAL:    n1 = (f1 == f2); break;
9882 	    case TYPE_NEQUAL:   n1 = (f1 != f2); break;
9883 	    case TYPE_GREATER:  n1 = (f1 > f2); break;
9884 	    case TYPE_GEQUAL:   n1 = (f1 >= f2); break;
9885 	    case TYPE_SMALLER:  n1 = (f1 < f2); break;
9886 	    case TYPE_SEQUAL:   n1 = (f1 <= f2); break;
9887 	    case TYPE_UNKNOWN:
9888 	    case TYPE_MATCH:
9889 	    case TYPE_NOMATCH:  break;  /* avoid gcc warning */
9890 	}
9891     }
9892 #endif
9893 
9894     /*
9895 	* If one of the two variables is a number, compare as a number.
9896 	* When using "=~" or "!~", always compare as string.
9897 	*/
9898     else if ((typ1->v_type == VAR_NUMBER || typ2->v_type == VAR_NUMBER)
9899 	    && type != TYPE_MATCH && type != TYPE_NOMATCH)
9900     {
9901 	n1 = tv_get_number(typ1);
9902 	n2 = tv_get_number(typ2);
9903 	switch (type)
9904 	{
9905 	    case TYPE_EQUAL:    n1 = (n1 == n2); break;
9906 	    case TYPE_NEQUAL:   n1 = (n1 != n2); break;
9907 	    case TYPE_GREATER:  n1 = (n1 > n2); break;
9908 	    case TYPE_GEQUAL:   n1 = (n1 >= n2); break;
9909 	    case TYPE_SMALLER:  n1 = (n1 < n2); break;
9910 	    case TYPE_SEQUAL:   n1 = (n1 <= n2); break;
9911 	    case TYPE_UNKNOWN:
9912 	    case TYPE_MATCH:
9913 	    case TYPE_NOMATCH:  break;  /* avoid gcc warning */
9914 	}
9915     }
9916     else
9917     {
9918 	s1 = tv_get_string_buf(typ1, buf1);
9919 	s2 = tv_get_string_buf(typ2, buf2);
9920 	if (type != TYPE_MATCH && type != TYPE_NOMATCH)
9921 	    i = ic ? MB_STRICMP(s1, s2) : STRCMP(s1, s2);
9922 	else
9923 	    i = 0;
9924 	n1 = FALSE;
9925 	switch (type)
9926 	{
9927 	    case TYPE_EQUAL:    n1 = (i == 0); break;
9928 	    case TYPE_NEQUAL:   n1 = (i != 0); break;
9929 	    case TYPE_GREATER:  n1 = (i > 0); break;
9930 	    case TYPE_GEQUAL:   n1 = (i >= 0); break;
9931 	    case TYPE_SMALLER:  n1 = (i < 0); break;
9932 	    case TYPE_SEQUAL:   n1 = (i <= 0); break;
9933 
9934 	    case TYPE_MATCH:
9935 	    case TYPE_NOMATCH:
9936 		    n1 = pattern_match(s2, s1, ic);
9937 		    if (type == TYPE_NOMATCH)
9938 			n1 = !n1;
9939 		    break;
9940 
9941 	    case TYPE_UNKNOWN:  break;  /* avoid gcc warning */
9942 	}
9943     }
9944     clear_tv(typ1);
9945     typ1->v_type = VAR_NUMBER;
9946     typ1->vval.v_number = n1;
9947 
9948     return OK;
9949 }
9950 
9951     char_u *
9952 typval_tostring(typval_T *arg)
9953 {
9954     char_u	*tofree;
9955     char_u	numbuf[NUMBUFLEN];
9956     char_u	*ret = NULL;
9957 
9958     if (arg == NULL)
9959 	return vim_strsave((char_u *)"(does not exist)");
9960     ret = tv2string(arg, &tofree, numbuf, 0);
9961     /* Make a copy if we have a value but it's not in allocated memory. */
9962     if (ret != NULL && tofree == NULL)
9963 	ret = vim_strsave(ret);
9964     return ret;
9965 }
9966 
9967     int
9968 var_exists(char_u *var)
9969 {
9970     char_u	*name;
9971     char_u	*tofree;
9972     typval_T    tv;
9973     int		len = 0;
9974     int		n = FALSE;
9975 
9976     /* get_name_len() takes care of expanding curly braces */
9977     name = var;
9978     len = get_name_len(&var, &tofree, TRUE, FALSE);
9979     if (len > 0)
9980     {
9981 	if (tofree != NULL)
9982 	    name = tofree;
9983 	n = (get_var_tv(name, len, &tv, NULL, FALSE, TRUE) == OK);
9984 	if (n)
9985 	{
9986 	    /* handle d.key, l[idx], f(expr) */
9987 	    n = (handle_subscript(&var, &tv, TRUE, FALSE) == OK);
9988 	    if (n)
9989 		clear_tv(&tv);
9990 	}
9991     }
9992     if (*var != NUL)
9993 	n = FALSE;
9994 
9995     vim_free(tofree);
9996     return n;
9997 }
9998 
9999 #endif /* FEAT_EVAL */
10000 
10001 
10002 #if defined(FEAT_MODIFY_FNAME) || defined(FEAT_EVAL) || defined(PROTO)
10003 
10004 #ifdef MSWIN
10005 /*
10006  * Functions for ":8" filename modifier: get 8.3 version of a filename.
10007  */
10008 
10009 /*
10010  * Get the short path (8.3) for the filename in "fnamep".
10011  * Only works for a valid file name.
10012  * When the path gets longer "fnamep" is changed and the allocated buffer
10013  * is put in "bufp".
10014  * *fnamelen is the length of "fnamep" and set to 0 for a nonexistent path.
10015  * Returns OK on success, FAIL on failure.
10016  */
10017     static int
10018 get_short_pathname(char_u **fnamep, char_u **bufp, int *fnamelen)
10019 {
10020     int		l, len;
10021     char_u	*newbuf;
10022 
10023     len = *fnamelen;
10024     l = GetShortPathName((LPSTR)*fnamep, (LPSTR)*fnamep, len);
10025     if (l > len - 1)
10026     {
10027 	/* If that doesn't work (not enough space), then save the string
10028 	 * and try again with a new buffer big enough. */
10029 	newbuf = vim_strnsave(*fnamep, l);
10030 	if (newbuf == NULL)
10031 	    return FAIL;
10032 
10033 	vim_free(*bufp);
10034 	*fnamep = *bufp = newbuf;
10035 
10036 	/* Really should always succeed, as the buffer is big enough. */
10037 	l = GetShortPathName((LPSTR)*fnamep, (LPSTR)*fnamep, l+1);
10038     }
10039 
10040     *fnamelen = l;
10041     return OK;
10042 }
10043 
10044 /*
10045  * Get the short path (8.3) for the filename in "fname". The converted
10046  * path is returned in "bufp".
10047  *
10048  * Some of the directories specified in "fname" may not exist. This function
10049  * will shorten the existing directories at the beginning of the path and then
10050  * append the remaining non-existing path.
10051  *
10052  * fname - Pointer to the filename to shorten.  On return, contains the
10053  *	   pointer to the shortened pathname
10054  * bufp -  Pointer to an allocated buffer for the filename.
10055  * fnamelen - Length of the filename pointed to by fname
10056  *
10057  * Returns OK on success (or nothing done) and FAIL on failure (out of memory).
10058  */
10059     static int
10060 shortpath_for_invalid_fname(
10061     char_u	**fname,
10062     char_u	**bufp,
10063     int		*fnamelen)
10064 {
10065     char_u	*short_fname, *save_fname, *pbuf_unused;
10066     char_u	*endp, *save_endp;
10067     char_u	ch;
10068     int		old_len, len;
10069     int		new_len, sfx_len;
10070     int		retval = OK;
10071 
10072     /* Make a copy */
10073     old_len = *fnamelen;
10074     save_fname = vim_strnsave(*fname, old_len);
10075     pbuf_unused = NULL;
10076     short_fname = NULL;
10077 
10078     endp = save_fname + old_len - 1; /* Find the end of the copy */
10079     save_endp = endp;
10080 
10081     /*
10082      * Try shortening the supplied path till it succeeds by removing one
10083      * directory at a time from the tail of the path.
10084      */
10085     len = 0;
10086     for (;;)
10087     {
10088 	/* go back one path-separator */
10089 	while (endp > save_fname && !after_pathsep(save_fname, endp + 1))
10090 	    --endp;
10091 	if (endp <= save_fname)
10092 	    break;		/* processed the complete path */
10093 
10094 	/*
10095 	 * Replace the path separator with a NUL and try to shorten the
10096 	 * resulting path.
10097 	 */
10098 	ch = *endp;
10099 	*endp = 0;
10100 	short_fname = save_fname;
10101 	len = (int)STRLEN(short_fname) + 1;
10102 	if (get_short_pathname(&short_fname, &pbuf_unused, &len) == FAIL)
10103 	{
10104 	    retval = FAIL;
10105 	    goto theend;
10106 	}
10107 	*endp = ch;	/* preserve the string */
10108 
10109 	if (len > 0)
10110 	    break;	/* successfully shortened the path */
10111 
10112 	/* failed to shorten the path. Skip the path separator */
10113 	--endp;
10114     }
10115 
10116     if (len > 0)
10117     {
10118 	/*
10119 	 * Succeeded in shortening the path. Now concatenate the shortened
10120 	 * path with the remaining path at the tail.
10121 	 */
10122 
10123 	/* Compute the length of the new path. */
10124 	sfx_len = (int)(save_endp - endp) + 1;
10125 	new_len = len + sfx_len;
10126 
10127 	*fnamelen = new_len;
10128 	vim_free(*bufp);
10129 	if (new_len > old_len)
10130 	{
10131 	    /* There is not enough space in the currently allocated string,
10132 	     * copy it to a buffer big enough. */
10133 	    *fname = *bufp = vim_strnsave(short_fname, new_len);
10134 	    if (*fname == NULL)
10135 	    {
10136 		retval = FAIL;
10137 		goto theend;
10138 	    }
10139 	}
10140 	else
10141 	{
10142 	    /* Transfer short_fname to the main buffer (it's big enough),
10143 	     * unless get_short_pathname() did its work in-place. */
10144 	    *fname = *bufp = save_fname;
10145 	    if (short_fname != save_fname)
10146 		vim_strncpy(save_fname, short_fname, len);
10147 	    save_fname = NULL;
10148 	}
10149 
10150 	/* concat the not-shortened part of the path */
10151 	vim_strncpy(*fname + len, endp, sfx_len);
10152 	(*fname)[new_len] = NUL;
10153     }
10154 
10155 theend:
10156     vim_free(pbuf_unused);
10157     vim_free(save_fname);
10158 
10159     return retval;
10160 }
10161 
10162 /*
10163  * Get a pathname for a partial path.
10164  * Returns OK for success, FAIL for failure.
10165  */
10166     static int
10167 shortpath_for_partial(
10168     char_u	**fnamep,
10169     char_u	**bufp,
10170     int		*fnamelen)
10171 {
10172     int		sepcount, len, tflen;
10173     char_u	*p;
10174     char_u	*pbuf, *tfname;
10175     int		hasTilde;
10176 
10177     /* Count up the path separators from the RHS.. so we know which part
10178      * of the path to return. */
10179     sepcount = 0;
10180     for (p = *fnamep; p < *fnamep + *fnamelen; MB_PTR_ADV(p))
10181 	if (vim_ispathsep(*p))
10182 	    ++sepcount;
10183 
10184     /* Need full path first (use expand_env() to remove a "~/") */
10185     hasTilde = (**fnamep == '~');
10186     if (hasTilde)
10187 	pbuf = tfname = expand_env_save(*fnamep);
10188     else
10189 	pbuf = tfname = FullName_save(*fnamep, FALSE);
10190 
10191     len = tflen = (int)STRLEN(tfname);
10192 
10193     if (get_short_pathname(&tfname, &pbuf, &len) == FAIL)
10194 	return FAIL;
10195 
10196     if (len == 0)
10197     {
10198 	/* Don't have a valid filename, so shorten the rest of the
10199 	 * path if we can. This CAN give us invalid 8.3 filenames, but
10200 	 * there's not a lot of point in guessing what it might be.
10201 	 */
10202 	len = tflen;
10203 	if (shortpath_for_invalid_fname(&tfname, &pbuf, &len) == FAIL)
10204 	    return FAIL;
10205     }
10206 
10207     /* Count the paths backward to find the beginning of the desired string. */
10208     for (p = tfname + len - 1; p >= tfname; --p)
10209     {
10210 	if (has_mbyte)
10211 	    p -= mb_head_off(tfname, p);
10212 	if (vim_ispathsep(*p))
10213 	{
10214 	    if (sepcount == 0 || (hasTilde && sepcount == 1))
10215 		break;
10216 	    else
10217 		sepcount --;
10218 	}
10219     }
10220     if (hasTilde)
10221     {
10222 	--p;
10223 	if (p >= tfname)
10224 	    *p = '~';
10225 	else
10226 	    return FAIL;
10227     }
10228     else
10229 	++p;
10230 
10231     /* Copy in the string - p indexes into tfname - allocated at pbuf */
10232     vim_free(*bufp);
10233     *fnamelen = (int)STRLEN(p);
10234     *bufp = pbuf;
10235     *fnamep = p;
10236 
10237     return OK;
10238 }
10239 #endif // MSWIN
10240 
10241 /*
10242  * Adjust a filename, according to a string of modifiers.
10243  * *fnamep must be NUL terminated when called.  When returning, the length is
10244  * determined by *fnamelen.
10245  * Returns VALID_ flags or -1 for failure.
10246  * When there is an error, *fnamep is set to NULL.
10247  */
10248     int
10249 modify_fname(
10250     char_u	*src,		// string with modifiers
10251     int		tilde_file,	// "~" is a file name, not $HOME
10252     int		*usedlen,	// characters after src that are used
10253     char_u	**fnamep,	// file name so far
10254     char_u	**bufp,		// buffer for allocated file name or NULL
10255     int		*fnamelen)	// length of fnamep
10256 {
10257     int		valid = 0;
10258     char_u	*tail;
10259     char_u	*s, *p, *pbuf;
10260     char_u	dirname[MAXPATHL];
10261     int		c;
10262     int		has_fullname = 0;
10263 #ifdef MSWIN
10264     char_u	*fname_start = *fnamep;
10265     int		has_shortname = 0;
10266 #endif
10267 
10268 repeat:
10269     /* ":p" - full path/file_name */
10270     if (src[*usedlen] == ':' && src[*usedlen + 1] == 'p')
10271     {
10272 	has_fullname = 1;
10273 
10274 	valid |= VALID_PATH;
10275 	*usedlen += 2;
10276 
10277 	/* Expand "~/path" for all systems and "~user/path" for Unix and VMS */
10278 	if ((*fnamep)[0] == '~'
10279 #if !defined(UNIX) && !(defined(VMS) && defined(USER_HOME))
10280 		&& ((*fnamep)[1] == '/'
10281 # ifdef BACKSLASH_IN_FILENAME
10282 		    || (*fnamep)[1] == '\\'
10283 # endif
10284 		    || (*fnamep)[1] == NUL)
10285 #endif
10286 		&& !(tilde_file && (*fnamep)[1] == NUL)
10287 	   )
10288 	{
10289 	    *fnamep = expand_env_save(*fnamep);
10290 	    vim_free(*bufp);	/* free any allocated file name */
10291 	    *bufp = *fnamep;
10292 	    if (*fnamep == NULL)
10293 		return -1;
10294 	}
10295 
10296 	/* When "/." or "/.." is used: force expansion to get rid of it. */
10297 	for (p = *fnamep; *p != NUL; MB_PTR_ADV(p))
10298 	{
10299 	    if (vim_ispathsep(*p)
10300 		    && p[1] == '.'
10301 		    && (p[2] == NUL
10302 			|| vim_ispathsep(p[2])
10303 			|| (p[2] == '.'
10304 			    && (p[3] == NUL || vim_ispathsep(p[3])))))
10305 		break;
10306 	}
10307 
10308 	/* FullName_save() is slow, don't use it when not needed. */
10309 	if (*p != NUL || !vim_isAbsName(*fnamep))
10310 	{
10311 	    *fnamep = FullName_save(*fnamep, *p != NUL);
10312 	    vim_free(*bufp);	/* free any allocated file name */
10313 	    *bufp = *fnamep;
10314 	    if (*fnamep == NULL)
10315 		return -1;
10316 	}
10317 
10318 #ifdef MSWIN
10319 # if _WIN32_WINNT >= 0x0500
10320 	if (vim_strchr(*fnamep, '~') != NULL)
10321 	{
10322 	    /* Expand 8.3 filename to full path.  Needed to make sure the same
10323 	     * file does not have two different names.
10324 	     * Note: problem does not occur if _WIN32_WINNT < 0x0500. */
10325 	    p = alloc(_MAX_PATH + 1);
10326 	    if (p != NULL)
10327 	    {
10328 		if (GetLongPathName((LPSTR)*fnamep, (LPSTR)p, _MAX_PATH))
10329 		{
10330 		    vim_free(*bufp);
10331 		    *bufp = *fnamep = p;
10332 		}
10333 		else
10334 		    vim_free(p);
10335 	    }
10336 	}
10337 # endif
10338 #endif
10339 	/* Append a path separator to a directory. */
10340 	if (mch_isdir(*fnamep))
10341 	{
10342 	    /* Make room for one or two extra characters. */
10343 	    *fnamep = vim_strnsave(*fnamep, (int)STRLEN(*fnamep) + 2);
10344 	    vim_free(*bufp);	/* free any allocated file name */
10345 	    *bufp = *fnamep;
10346 	    if (*fnamep == NULL)
10347 		return -1;
10348 	    add_pathsep(*fnamep);
10349 	}
10350     }
10351 
10352     /* ":." - path relative to the current directory */
10353     /* ":~" - path relative to the home directory */
10354     /* ":8" - shortname path - postponed till after */
10355     while (src[*usedlen] == ':'
10356 		  && ((c = src[*usedlen + 1]) == '.' || c == '~' || c == '8'))
10357     {
10358 	*usedlen += 2;
10359 	if (c == '8')
10360 	{
10361 #ifdef MSWIN
10362 	    has_shortname = 1; /* Postpone this. */
10363 #endif
10364 	    continue;
10365 	}
10366 	pbuf = NULL;
10367 	/* Need full path first (use expand_env() to remove a "~/") */
10368 	if (!has_fullname)
10369 	{
10370 	    if (c == '.' && **fnamep == '~')
10371 		p = pbuf = expand_env_save(*fnamep);
10372 	    else
10373 		p = pbuf = FullName_save(*fnamep, FALSE);
10374 	}
10375 	else
10376 	    p = *fnamep;
10377 
10378 	has_fullname = 0;
10379 
10380 	if (p != NULL)
10381 	{
10382 	    if (c == '.')
10383 	    {
10384 		mch_dirname(dirname, MAXPATHL);
10385 		s = shorten_fname(p, dirname);
10386 		if (s != NULL)
10387 		{
10388 		    *fnamep = s;
10389 		    if (pbuf != NULL)
10390 		    {
10391 			vim_free(*bufp);   /* free any allocated file name */
10392 			*bufp = pbuf;
10393 			pbuf = NULL;
10394 		    }
10395 		}
10396 	    }
10397 	    else
10398 	    {
10399 		home_replace(NULL, p, dirname, MAXPATHL, TRUE);
10400 		/* Only replace it when it starts with '~' */
10401 		if (*dirname == '~')
10402 		{
10403 		    s = vim_strsave(dirname);
10404 		    if (s != NULL)
10405 		    {
10406 			*fnamep = s;
10407 			vim_free(*bufp);
10408 			*bufp = s;
10409 		    }
10410 		}
10411 	    }
10412 	    vim_free(pbuf);
10413 	}
10414     }
10415 
10416     tail = gettail(*fnamep);
10417     *fnamelen = (int)STRLEN(*fnamep);
10418 
10419     /* ":h" - head, remove "/file_name", can be repeated  */
10420     /* Don't remove the first "/" or "c:\" */
10421     while (src[*usedlen] == ':' && src[*usedlen + 1] == 'h')
10422     {
10423 	valid |= VALID_HEAD;
10424 	*usedlen += 2;
10425 	s = get_past_head(*fnamep);
10426 	while (tail > s && after_pathsep(s, tail))
10427 	    MB_PTR_BACK(*fnamep, tail);
10428 	*fnamelen = (int)(tail - *fnamep);
10429 #ifdef VMS
10430 	if (*fnamelen > 0)
10431 	    *fnamelen += 1; /* the path separator is part of the path */
10432 #endif
10433 	if (*fnamelen == 0)
10434 	{
10435 	    /* Result is empty.  Turn it into "." to make ":cd %:h" work. */
10436 	    p = vim_strsave((char_u *)".");
10437 	    if (p == NULL)
10438 		return -1;
10439 	    vim_free(*bufp);
10440 	    *bufp = *fnamep = tail = p;
10441 	    *fnamelen = 1;
10442 	}
10443 	else
10444 	{
10445 	    while (tail > s && !after_pathsep(s, tail))
10446 		MB_PTR_BACK(*fnamep, tail);
10447 	}
10448     }
10449 
10450     /* ":8" - shortname  */
10451     if (src[*usedlen] == ':' && src[*usedlen + 1] == '8')
10452     {
10453 	*usedlen += 2;
10454 #ifdef MSWIN
10455 	has_shortname = 1;
10456 #endif
10457     }
10458 
10459 #ifdef MSWIN
10460     /*
10461      * Handle ":8" after we have done 'heads' and before we do 'tails'.
10462      */
10463     if (has_shortname)
10464     {
10465 	/* Copy the string if it is shortened by :h and when it wasn't copied
10466 	 * yet, because we are going to change it in place.  Avoids changing
10467 	 * the buffer name for "%:8". */
10468 	if (*fnamelen < (int)STRLEN(*fnamep) || *fnamep == fname_start)
10469 	{
10470 	    p = vim_strnsave(*fnamep, *fnamelen);
10471 	    if (p == NULL)
10472 		return -1;
10473 	    vim_free(*bufp);
10474 	    *bufp = *fnamep = p;
10475 	}
10476 
10477 	/* Split into two implementations - makes it easier.  First is where
10478 	 * there isn't a full name already, second is where there is. */
10479 	if (!has_fullname && !vim_isAbsName(*fnamep))
10480 	{
10481 	    if (shortpath_for_partial(fnamep, bufp, fnamelen) == FAIL)
10482 		return -1;
10483 	}
10484 	else
10485 	{
10486 	    int		l = *fnamelen;
10487 
10488 	    /* Simple case, already have the full-name.
10489 	     * Nearly always shorter, so try first time. */
10490 	    if (get_short_pathname(fnamep, bufp, &l) == FAIL)
10491 		return -1;
10492 
10493 	    if (l == 0)
10494 	    {
10495 		/* Couldn't find the filename, search the paths. */
10496 		l = *fnamelen;
10497 		if (shortpath_for_invalid_fname(fnamep, bufp, &l) == FAIL)
10498 		    return -1;
10499 	    }
10500 	    *fnamelen = l;
10501 	}
10502     }
10503 #endif // MSWIN
10504 
10505     /* ":t" - tail, just the basename */
10506     if (src[*usedlen] == ':' && src[*usedlen + 1] == 't')
10507     {
10508 	*usedlen += 2;
10509 	*fnamelen -= (int)(tail - *fnamep);
10510 	*fnamep = tail;
10511     }
10512 
10513     /* ":e" - extension, can be repeated */
10514     /* ":r" - root, without extension, can be repeated */
10515     while (src[*usedlen] == ':'
10516 	    && (src[*usedlen + 1] == 'e' || src[*usedlen + 1] == 'r'))
10517     {
10518 	/* find a '.' in the tail:
10519 	 * - for second :e: before the current fname
10520 	 * - otherwise: The last '.'
10521 	 */
10522 	if (src[*usedlen + 1] == 'e' && *fnamep > tail)
10523 	    s = *fnamep - 2;
10524 	else
10525 	    s = *fnamep + *fnamelen - 1;
10526 	for ( ; s > tail; --s)
10527 	    if (s[0] == '.')
10528 		break;
10529 	if (src[*usedlen + 1] == 'e')		/* :e */
10530 	{
10531 	    if (s > tail)
10532 	    {
10533 		*fnamelen += (int)(*fnamep - (s + 1));
10534 		*fnamep = s + 1;
10535 #ifdef VMS
10536 		/* cut version from the extension */
10537 		s = *fnamep + *fnamelen - 1;
10538 		for ( ; s > *fnamep; --s)
10539 		    if (s[0] == ';')
10540 			break;
10541 		if (s > *fnamep)
10542 		    *fnamelen = s - *fnamep;
10543 #endif
10544 	    }
10545 	    else if (*fnamep <= tail)
10546 		*fnamelen = 0;
10547 	}
10548 	else				/* :r */
10549 	{
10550 	    if (s > tail)	/* remove one extension */
10551 		*fnamelen = (int)(s - *fnamep);
10552 	}
10553 	*usedlen += 2;
10554     }
10555 
10556     /* ":s?pat?foo?" - substitute */
10557     /* ":gs?pat?foo?" - global substitute */
10558     if (src[*usedlen] == ':'
10559 	    && (src[*usedlen + 1] == 's'
10560 		|| (src[*usedlen + 1] == 'g' && src[*usedlen + 2] == 's')))
10561     {
10562 	char_u	    *str;
10563 	char_u	    *pat;
10564 	char_u	    *sub;
10565 	int	    sep;
10566 	char_u	    *flags;
10567 	int	    didit = FALSE;
10568 
10569 	flags = (char_u *)"";
10570 	s = src + *usedlen + 2;
10571 	if (src[*usedlen + 1] == 'g')
10572 	{
10573 	    flags = (char_u *)"g";
10574 	    ++s;
10575 	}
10576 
10577 	sep = *s++;
10578 	if (sep)
10579 	{
10580 	    /* find end of pattern */
10581 	    p = vim_strchr(s, sep);
10582 	    if (p != NULL)
10583 	    {
10584 		pat = vim_strnsave(s, (int)(p - s));
10585 		if (pat != NULL)
10586 		{
10587 		    s = p + 1;
10588 		    /* find end of substitution */
10589 		    p = vim_strchr(s, sep);
10590 		    if (p != NULL)
10591 		    {
10592 			sub = vim_strnsave(s, (int)(p - s));
10593 			str = vim_strnsave(*fnamep, *fnamelen);
10594 			if (sub != NULL && str != NULL)
10595 			{
10596 			    *usedlen = (int)(p + 1 - src);
10597 			    s = do_string_sub(str, pat, sub, NULL, flags);
10598 			    if (s != NULL)
10599 			    {
10600 				*fnamep = s;
10601 				*fnamelen = (int)STRLEN(s);
10602 				vim_free(*bufp);
10603 				*bufp = s;
10604 				didit = TRUE;
10605 			    }
10606 			}
10607 			vim_free(sub);
10608 			vim_free(str);
10609 		    }
10610 		    vim_free(pat);
10611 		}
10612 	    }
10613 	    /* after using ":s", repeat all the modifiers */
10614 	    if (didit)
10615 		goto repeat;
10616 	}
10617     }
10618 
10619     if (src[*usedlen] == ':' && src[*usedlen + 1] == 'S')
10620     {
10621 	/* vim_strsave_shellescape() needs a NUL terminated string. */
10622 	c = (*fnamep)[*fnamelen];
10623 	if (c != NUL)
10624 	    (*fnamep)[*fnamelen] = NUL;
10625 	p = vim_strsave_shellescape(*fnamep, FALSE, FALSE);
10626 	if (c != NUL)
10627 	    (*fnamep)[*fnamelen] = c;
10628 	if (p == NULL)
10629 	    return -1;
10630 	vim_free(*bufp);
10631 	*bufp = *fnamep = p;
10632 	*fnamelen = (int)STRLEN(p);
10633 	*usedlen += 2;
10634     }
10635 
10636     return valid;
10637 }
10638 
10639 /*
10640  * Perform a substitution on "str" with pattern "pat" and substitute "sub".
10641  * When "sub" is NULL "expr" is used, must be a VAR_FUNC or VAR_PARTIAL.
10642  * "flags" can be "g" to do a global substitute.
10643  * Returns an allocated string, NULL for error.
10644  */
10645     char_u *
10646 do_string_sub(
10647     char_u	*str,
10648     char_u	*pat,
10649     char_u	*sub,
10650     typval_T	*expr,
10651     char_u	*flags)
10652 {
10653     int		sublen;
10654     regmatch_T	regmatch;
10655     int		i;
10656     int		do_all;
10657     char_u	*tail;
10658     char_u	*end;
10659     garray_T	ga;
10660     char_u	*ret;
10661     char_u	*save_cpo;
10662     char_u	*zero_width = NULL;
10663 
10664     /* Make 'cpoptions' empty, so that the 'l' flag doesn't work here */
10665     save_cpo = p_cpo;
10666     p_cpo = empty_option;
10667 
10668     ga_init2(&ga, 1, 200);
10669 
10670     do_all = (flags[0] == 'g');
10671 
10672     regmatch.rm_ic = p_ic;
10673     regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
10674     if (regmatch.regprog != NULL)
10675     {
10676 	tail = str;
10677 	end = str + STRLEN(str);
10678 	while (vim_regexec_nl(&regmatch, str, (colnr_T)(tail - str)))
10679 	{
10680 	    /* Skip empty match except for first match. */
10681 	    if (regmatch.startp[0] == regmatch.endp[0])
10682 	    {
10683 		if (zero_width == regmatch.startp[0])
10684 		{
10685 		    /* avoid getting stuck on a match with an empty string */
10686 		    i = MB_PTR2LEN(tail);
10687 		    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail,
10688 								   (size_t)i);
10689 		    ga.ga_len += i;
10690 		    tail += i;
10691 		    continue;
10692 		}
10693 		zero_width = regmatch.startp[0];
10694 	    }
10695 
10696 	    /*
10697 	     * Get some space for a temporary buffer to do the substitution
10698 	     * into.  It will contain:
10699 	     * - The text up to where the match is.
10700 	     * - The substituted text.
10701 	     * - The text after the match.
10702 	     */
10703 	    sublen = vim_regsub(&regmatch, sub, expr, tail, FALSE, TRUE, FALSE);
10704 	    if (ga_grow(&ga, (int)((end - tail) + sublen -
10705 			    (regmatch.endp[0] - regmatch.startp[0]))) == FAIL)
10706 	    {
10707 		ga_clear(&ga);
10708 		break;
10709 	    }
10710 
10711 	    /* copy the text up to where the match is */
10712 	    i = (int)(regmatch.startp[0] - tail);
10713 	    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail, (size_t)i);
10714 	    /* add the substituted text */
10715 	    (void)vim_regsub(&regmatch, sub, expr, (char_u *)ga.ga_data
10716 					  + ga.ga_len + i, TRUE, TRUE, FALSE);
10717 	    ga.ga_len += i + sublen - 1;
10718 	    tail = regmatch.endp[0];
10719 	    if (*tail == NUL)
10720 		break;
10721 	    if (!do_all)
10722 		break;
10723 	}
10724 
10725 	if (ga.ga_data != NULL)
10726 	    STRCPY((char *)ga.ga_data + ga.ga_len, tail);
10727 
10728 	vim_regfree(regmatch.regprog);
10729     }
10730 
10731     ret = vim_strsave(ga.ga_data == NULL ? str : (char_u *)ga.ga_data);
10732     ga_clear(&ga);
10733     if (p_cpo == empty_option)
10734 	p_cpo = save_cpo;
10735     else
10736 	/* Darn, evaluating {sub} expression or {expr} changed the value. */
10737 	free_string_option(save_cpo);
10738 
10739     return ret;
10740 }
10741 
10742     static int
10743 filter_map_one(typval_T *tv, typval_T *expr, int map, int *remp)
10744 {
10745     typval_T	rettv;
10746     typval_T	argv[3];
10747     int		retval = FAIL;
10748 
10749     copy_tv(tv, &vimvars[VV_VAL].vv_tv);
10750     argv[0] = vimvars[VV_KEY].vv_tv;
10751     argv[1] = vimvars[VV_VAL].vv_tv;
10752     if (eval_expr_typval(expr, argv, 2, &rettv) == FAIL)
10753 	goto theend;
10754     if (map)
10755     {
10756 	/* map(): replace the list item value */
10757 	clear_tv(tv);
10758 	rettv.v_lock = 0;
10759 	*tv = rettv;
10760     }
10761     else
10762     {
10763 	int	    error = FALSE;
10764 
10765 	/* filter(): when expr is zero remove the item */
10766 	*remp = (tv_get_number_chk(&rettv, &error) == 0);
10767 	clear_tv(&rettv);
10768 	/* On type error, nothing has been removed; return FAIL to stop the
10769 	 * loop.  The error message was given by tv_get_number_chk(). */
10770 	if (error)
10771 	    goto theend;
10772     }
10773     retval = OK;
10774 theend:
10775     clear_tv(&vimvars[VV_VAL].vv_tv);
10776     return retval;
10777 }
10778 
10779 
10780 /*
10781  * Implementation of map() and filter().
10782  */
10783     void
10784 filter_map(typval_T *argvars, typval_T *rettv, int map)
10785 {
10786     typval_T	*expr;
10787     listitem_T	*li, *nli;
10788     list_T	*l = NULL;
10789     dictitem_T	*di;
10790     hashtab_T	*ht;
10791     hashitem_T	*hi;
10792     dict_T	*d = NULL;
10793     typval_T	save_val;
10794     typval_T	save_key;
10795     blob_T	*b = NULL;
10796     int		rem;
10797     int		todo;
10798     char_u	*ermsg = (char_u *)(map ? "map()" : "filter()");
10799     char_u	*arg_errmsg = (char_u *)(map ? N_("map() argument")
10800 				   : N_("filter() argument"));
10801     int		save_did_emsg;
10802     int		idx = 0;
10803 
10804     if (argvars[0].v_type == VAR_BLOB)
10805     {
10806 	if ((b = argvars[0].vval.v_blob) == NULL)
10807 	    return;
10808     }
10809     else if (argvars[0].v_type == VAR_LIST)
10810     {
10811 	if ((l = argvars[0].vval.v_list) == NULL
10812 	      || (!map && var_check_lock(l->lv_lock, arg_errmsg, TRUE)))
10813 	    return;
10814     }
10815     else if (argvars[0].v_type == VAR_DICT)
10816     {
10817 	if ((d = argvars[0].vval.v_dict) == NULL
10818 	      || (!map && var_check_lock(d->dv_lock, arg_errmsg, TRUE)))
10819 	    return;
10820     }
10821     else
10822     {
10823 	semsg(_(e_listdictarg), ermsg);
10824 	return;
10825     }
10826 
10827     expr = &argvars[1];
10828     /* On type errors, the preceding call has already displayed an error
10829      * message.  Avoid a misleading error message for an empty string that
10830      * was not passed as argument. */
10831     if (expr->v_type != VAR_UNKNOWN)
10832     {
10833 	prepare_vimvar(VV_VAL, &save_val);
10834 
10835 	/* We reset "did_emsg" to be able to detect whether an error
10836 	 * occurred during evaluation of the expression. */
10837 	save_did_emsg = did_emsg;
10838 	did_emsg = FALSE;
10839 
10840 	prepare_vimvar(VV_KEY, &save_key);
10841 	if (argvars[0].v_type == VAR_DICT)
10842 	{
10843 	    vimvars[VV_KEY].vv_type = VAR_STRING;
10844 
10845 	    ht = &d->dv_hashtab;
10846 	    hash_lock(ht);
10847 	    todo = (int)ht->ht_used;
10848 	    for (hi = ht->ht_array; todo > 0; ++hi)
10849 	    {
10850 		if (!HASHITEM_EMPTY(hi))
10851 		{
10852 		    int r;
10853 
10854 		    --todo;
10855 		    di = HI2DI(hi);
10856 		    if (map && (var_check_lock(di->di_tv.v_lock,
10857 							   arg_errmsg, TRUE)
10858 				|| var_check_ro(di->di_flags,
10859 							   arg_errmsg, TRUE)))
10860 			break;
10861 		    vimvars[VV_KEY].vv_str = vim_strsave(di->di_key);
10862 		    r = filter_map_one(&di->di_tv, expr, map, &rem);
10863 		    clear_tv(&vimvars[VV_KEY].vv_tv);
10864 		    if (r == FAIL || did_emsg)
10865 			break;
10866 		    if (!map && rem)
10867 		    {
10868 			if (var_check_fixed(di->di_flags, arg_errmsg, TRUE)
10869 			    || var_check_ro(di->di_flags, arg_errmsg, TRUE))
10870 			    break;
10871 			dictitem_remove(d, di);
10872 		    }
10873 		}
10874 	    }
10875 	    hash_unlock(ht);
10876 	}
10877 	else if (argvars[0].v_type == VAR_BLOB)
10878 	{
10879 	    int		i;
10880 	    typval_T	tv;
10881 
10882 	    vimvars[VV_KEY].vv_type = VAR_NUMBER;
10883 	    for (i = 0; i < b->bv_ga.ga_len; i++)
10884 	    {
10885 		tv.v_type = VAR_NUMBER;
10886 		tv.vval.v_number = blob_get(b, i);
10887 		vimvars[VV_KEY].vv_nr = idx;
10888 		if (filter_map_one(&tv, expr, map, &rem) == FAIL || did_emsg)
10889 		    break;
10890 		if (tv.v_type != VAR_NUMBER)
10891 		{
10892 		    emsg(_(e_invalblob));
10893 		    return;
10894 		}
10895 		tv.v_type = VAR_NUMBER;
10896 		blob_set(b, i, tv.vval.v_number);
10897 		if (!map && rem)
10898 		{
10899 		    char_u *p = (char_u *)argvars[0].vval.v_blob->bv_ga.ga_data;
10900 
10901 		    mch_memmove(p + idx, p + i + 1,
10902 					      (size_t)b->bv_ga.ga_len - i - 1);
10903 		    --b->bv_ga.ga_len;
10904 		    --i;
10905 		}
10906 	    }
10907 	}
10908 	else
10909 	{
10910 	    // argvars[0].v_type == VAR_LIST
10911 	    vimvars[VV_KEY].vv_type = VAR_NUMBER;
10912 
10913 	    for (li = l->lv_first; li != NULL; li = nli)
10914 	    {
10915 		if (map && var_check_lock(li->li_tv.v_lock, arg_errmsg, TRUE))
10916 		    break;
10917 		nli = li->li_next;
10918 		vimvars[VV_KEY].vv_nr = idx;
10919 		if (filter_map_one(&li->li_tv, expr, map, &rem) == FAIL
10920 								  || did_emsg)
10921 		    break;
10922 		if (!map && rem)
10923 		    listitem_remove(l, li);
10924 		++idx;
10925 	    }
10926 	}
10927 
10928 	restore_vimvar(VV_KEY, &save_key);
10929 	restore_vimvar(VV_VAL, &save_val);
10930 
10931 	did_emsg |= save_did_emsg;
10932     }
10933 
10934     copy_tv(&argvars[0], rettv);
10935 }
10936 
10937 #endif /* defined(FEAT_MODIFY_FNAME) || defined(FEAT_EVAL) */
10938