patch 8.1.1933: the eval.c file is too bigv8.1.1933

Problem:    The eval.c file is too big.
Solution:   Move code related to variables to evalvars.c. (Yegappan
            Lakshmanan, closes #4868)

1 files changed, 38 insertions, 1869 deletions

diff --git a/src/eval.c b/src/eval.c
index 9a2642cbe8..7795f41dbf 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -20,15 +20,8 @@
 # include <float.h>
 #endif
 
-#define DICT_MAXNEST 100	/* maximum nesting of lists and dicts */
-
-static char *e_letunexp	= N_("E18: Unexpected characters in :let");
-static char *e_undefvar = N_("E121: Undefined variable: %s");
 static char *e_missbrac = N_("E111: Missing ']'");
 static char *e_dictrange = N_("E719: Cannot use [:] with a Dictionary");
-static char *e_letwrong = N_("E734: Wrong variable type for %s=");
-static char *e_illvar = N_("E461: Illegal variable name: %s");
-static char *e_cannot_mod = N_("E995: Cannot modify existing variable");
 #ifdef FEAT_FLOAT
 static char *e_float_as_string = N_("E806: using Float as a String");
 #endif
@@ -217,25 +210,7 @@ static struct vimvar
 static dictitem_T	vimvars_var;		/* variable used for v: */
 #define vimvarht  vimvardict.dv_hashtab
 
-static void ex_let_const(exarg_T *eap, int is_const);
-static int ex_let_vars(char_u *arg, typval_T *tv, int copy, int semicolon, int var_count, int is_const, char_u *nextchars);
-static char_u *skip_var_list(char_u *arg, int *var_count, int *semicolon);
-static char_u *skip_var_one(char_u *arg);
-static void list_glob_vars(int *first);
-static void list_buf_vars(int *first);
-static void list_win_vars(int *first);
-static void list_tab_vars(int *first);
-static void list_vim_vars(int *first);
-static void list_script_vars(int *first);
-static char_u *list_arg_vars(exarg_T *eap, char_u *arg, int *first);
-static char_u *ex_let_one(char_u *arg, typval_T *tv, int copy, int is_const, char_u *endchars, char_u *op);
-static void set_var_lval(lval_T *lp, char_u *endp, typval_T *rettv, int copy, int is_const, char_u *op);
 static int tv_op(typval_T *tv1, typval_T *tv2, char_u  *op);
-static void ex_unletlock(exarg_T *eap, char_u *argstart, int deep);
-static int do_unlet_var(lval_T *lp, char_u *name_end, int forceit);
-static int do_lock_var(lval_T *lp, char_u *name_end, int deep, int lock);
-static void item_lock(typval_T *tv, int deep, int lock);
-
 static int eval2(char_u **arg, typval_T *rettv, int evaluate);
 static int eval3(char_u **arg, typval_T *rettv, int evaluate);
 static int eval4(char_u **arg, typval_T *rettv, int evaluate);
@@ -248,18 +223,10 @@ static int get_string_tv(char_u **arg, typval_T *rettv, int evaluate);
 static int get_lit_string_tv(char_u **arg, typval_T *rettv, int evaluate);
 static int free_unref_items(int copyID);
 static int get_env_tv(char_u **arg, typval_T *rettv, int evaluate);
-static int get_env_len(char_u **arg);
-static int get_name_len(char_u **arg, char_u **alias, int evaluate, int verbose);
 static char_u *make_expanded_name(char_u *in_start, char_u *expr_start, char_u *expr_end, char_u *in_end);
-static int get_var_tv(char_u *name, int len, typval_T *rettv, dictitem_T **dip, int verbose, int no_autoload);
 static void check_vars(char_u *name, int len);
 static typval_T *alloc_string_tv(char_u *string);
-static void delete_var(hashtab_T *ht, hashitem_T *hi);
-static void list_one_var(dictitem_T *v, char *prefix, int *first);
-static void list_one_var_a(char *prefix, char_u *name, int type, char_u *string, int *first);
-static void set_var_const(char_u *name, typval_T *tv, int copy, int is_const);
 static int tv_check_lock(typval_T *tv, char_u *name, int use_gettext);
-static char_u *find_option_end(char_u **arg, int *opt_flags);
 
 /* for VIM_VERSION_ defines */
 #include "version.h"
@@ -267,7 +234,7 @@ static char_u *find_option_end(char_u **arg, int *opt_flags);
 /*
  * Return "n1" divided by "n2", taking care of dividing by zero.
  */
-	static varnumber_T
+	varnumber_T
 num_divide(varnumber_T n1, varnumber_T n2)
 {
     varnumber_T	result;
@@ -290,7 +257,7 @@ num_divide(varnumber_T n1, varnumber_T n2)
 /*
  * Return "n1" modulus "n2", taking care of dividing by zero.
  */
-	static varnumber_T
+	varnumber_T
 num_modulus(varnumber_T n1, varnumber_T n2)
 {
     // Give an error when n2 is 0?
@@ -978,6 +945,38 @@ eval_to_number(char_u *expr)
 }
 
 /*
+ * List Vim variables.
+ */
+    void
+list_vim_vars(int *first)
+{
+    list_hashtable_vars(&vimvarht, "v:", FALSE, first);
+}
+
+/*
+ * List script-local variables, if there is a script.
+ */
+    void
+list_script_vars(int *first)
+{
+    if (current_sctx.sc_sid > 0 && current_sctx.sc_sid <= ga_scripts.ga_len)
+	list_hashtable_vars(&SCRIPT_VARS(current_sctx.sc_sid),
+							   "s:", FALSE, first);
+}
+
+    int
+is_vimvarht(hashtab_T *ht)
+{
+    return ht == &vimvarht;
+}
+
+    int
+is_compatht(hashtab_T *ht)
+{
+    return ht == &compat_hashtab;
+}
+
+/*
  * Prepare v: variable "idx" to be used.
  * Save the current typeval in "save_tv".
  * When not used yet add the variable to the v: hashtable.
@@ -1237,849 +1236,6 @@ eval_foldexpr(char_u *arg, int *cp)
 #endif
 
 /*
- * Get a list of lines from a HERE document. The here document is a list of
- * lines surrounded by a marker.
- *	cmd << {marker}
- *	  {line1}
- *	  {line2}
- *	  ....
- *	{marker}
- *
- * The {marker} is a string. If the optional 'trim' word is supplied before the
- * marker, then the leading indentation before the lines (matching the
- * indentation in the 'cmd' line) is stripped.
- * Returns a List with {lines} or NULL.
- */
-    static list_T *
-heredoc_get(exarg_T *eap, char_u *cmd)
-{
-    char_u	*theline;
-    char_u	*marker;
-    list_T	*l;
-    char_u	*p;
-    int		marker_indent_len = 0;
-    int		text_indent_len = 0;
-    char_u	*text_indent = NULL;
-
-    if (eap->getline == NULL)
-    {
-	emsg(_("E991: cannot use =<< here"));
-	return NULL;
-    }
-
-    // Check for the optional 'trim' word before the marker
-    cmd = skipwhite(cmd);
-    if (STRNCMP(cmd, "trim", 4) == 0 && (cmd[4] == NUL || VIM_ISWHITE(cmd[4])))
-    {
-	cmd = skipwhite(cmd + 4);
-
-	// Trim the indentation from all the lines in the here document.
-	// The amount of indentation trimmed is the same as the indentation of
-	// the first line after the :let command line.  To find the end marker
-	// the indent of the :let command line is trimmed.
-	p = *eap->cmdlinep;
-	while (VIM_ISWHITE(*p))
-	{
-	    p++;
-	    marker_indent_len++;
-	}
-	text_indent_len = -1;
-    }
-
-    // The marker is the next word.
-    if (*cmd != NUL && *cmd != '"')
-    {
-	marker = skipwhite(cmd);
-	p = skiptowhite(marker);
-	if (*skipwhite(p) != NUL && *skipwhite(p) != '"')
-	{
-	    emsg(_(e_trailing));
-	    return NULL;
-	}
-	*p = NUL;
-	if (vim_islower(*marker))
-	{
-	    emsg(_("E221: Marker cannot start with lower case letter"));
-	    return NULL;
-	}
-    }
-    else
-    {
-	emsg(_("E172: Missing marker"));
-	return NULL;
-    }
-
-    l = list_alloc();
-    if (l == NULL)
-	return NULL;
-
-    for (;;)
-    {
-	int	mi = 0;
-	int	ti = 0;
-
-	theline = eap->getline(NUL, eap->cookie, 0, FALSE);
-	if (theline == NULL)
-	{
-	    semsg(_("E990: Missing end marker '%s'"), marker);
-	    break;
-	}
-
-	// with "trim": skip the indent matching the :let line to find the
-	// marker
-	if (marker_indent_len > 0
-		&& STRNCMP(theline, *eap->cmdlinep, marker_indent_len) == 0)
-	    mi = marker_indent_len;
-	if (STRCMP(marker, theline + mi) == 0)
-	{
-	    vim_free(theline);
-	    break;
-	}
-
-	if (text_indent_len == -1 && *theline != NUL)
-	{
-	    // set the text indent from the first line.
-	    p = theline;
-	    text_indent_len = 0;
-	    while (VIM_ISWHITE(*p))
-	    {
-		p++;
-		text_indent_len++;
-	    }
-	    text_indent = vim_strnsave(theline, text_indent_len);
-	}
-	// with "trim": skip the indent matching the first line
-	if (text_indent != NULL)
-	    for (ti = 0; ti < text_indent_len; ++ti)
-		if (theline[ti] != text_indent[ti])
-		    break;
-
-	if (list_append_string(l, theline + ti, -1) == FAIL)
-	    break;
-	vim_free(theline);
-    }
-    vim_free(text_indent);
-
-    return l;
-}
-
-/*
- * ":let"			list all variable values
- * ":let var1 var2"		list variable values
- * ":let var = expr"		assignment command.
- * ":let var += expr"		assignment command.
- * ":let var -= expr"		assignment command.
- * ":let var *= expr"		assignment command.
- * ":let var /= expr"		assignment command.
- * ":let var %= expr"		assignment command.
- * ":let var .= expr"		assignment command.
- * ":let var ..= expr"		assignment command.
- * ":let [var1, var2] = expr"	unpack list.
- */
-    void
-ex_let(exarg_T *eap)
-{
-    ex_let_const(eap, FALSE);
-}
-
-/*
- * ":const"			list all variable values
- * ":const var1 var2"		list variable values
- * ":const var = expr"		assignment command.
- * ":const [var1, var2] = expr"	unpack list.
- */
-    void
-ex_const(exarg_T *eap)
-{
-    ex_let_const(eap, TRUE);
-}
-
-    static void
-ex_let_const(exarg_T *eap, int is_const)
-{
-    char_u	*arg = eap->arg;
-    char_u	*expr = NULL;
-    typval_T	rettv;
-    int		i;
-    int		var_count = 0;
-    int		semicolon = 0;
-    char_u	op[2];
-    char_u	*argend;
-    int		first = TRUE;
-    int		concat;
-
-    argend = skip_var_list(arg, &var_count, &semicolon);
-    if (argend == NULL)
-	return;
-    if (argend > arg && argend[-1] == '.')  // for var.='str'
-	--argend;
-    expr = skipwhite(argend);
-    concat = expr[0] == '.'
-	&& ((expr[1] == '=' && current_sctx.sc_version < 2)
-		|| (expr[1] == '.' && expr[2] == '='));
-    if (*expr != '=' && !((vim_strchr((char_u *)"+-*/%", *expr) != NULL
-						 && expr[1] == '=') || concat))
-    {
-	/*
-	 * ":let" without "=": list variables
-	 */
-	if (*arg == '[')
-	    emsg(_(e_invarg));
-	else if (expr[0] == '.')
-	    emsg(_("E985: .= is not supported with script version 2"));
-	else if (!ends_excmd(*arg))
-	    /* ":let var1 var2" */
-	    arg = list_arg_vars(eap, arg, &first);
-	else if (!eap->skip)
-	{
-	    /* ":let" */
-	    list_glob_vars(&first);
-	    list_buf_vars(&first);
-	    list_win_vars(&first);
-	    list_tab_vars(&first);
-	    list_script_vars(&first);
-	    list_func_vars(&first);
-	    list_vim_vars(&first);
-	}
-	eap->nextcmd = check_nextcmd(arg);
-    }
-    else if (expr[0] == '=' && expr[1] == '<' && expr[2] == '<')
-    {
-	list_T	*l;
-
-	// HERE document
-	l = heredoc_get(eap, expr + 3);
-	if (l != NULL)
-	{
-	    rettv_list_set(&rettv, l);
-	    op[0] = '=';
-	    op[1] = NUL;
-	    (void)ex_let_vars(eap->arg, &rettv, FALSE, semicolon, var_count,
-								is_const, op);
-	    clear_tv(&rettv);
-	}
-    }
-    else
-    {
-	op[0] = '=';
-	op[1] = NUL;
-	if (*expr != '=')
-	{
-	    if (vim_strchr((char_u *)"+-*/%.", *expr) != NULL)
-	    {
-		op[0] = *expr;   // +=, -=, *=, /=, %= or .=
-		if (expr[0] == '.' && expr[1] == '.') // ..=
-		    ++expr;
-	    }
-	    expr = skipwhite(expr + 2);
-	}
-	else
-	    expr = skipwhite(expr + 1);
-
-	if (eap->skip)
-	    ++emsg_skip;
-	i = eval0(expr, &rettv, &eap->nextcmd, !eap->skip);
-	if (eap->skip)
-	{
-	    if (i != FAIL)
-		clear_tv(&rettv);
-	    --emsg_skip;
-	}
-	else if (i != FAIL)
-	{
-	    (void)ex_let_vars(eap->arg, &rettv, FALSE, semicolon, var_count,
-								 is_const, op);
-	    clear_tv(&rettv);
-	}
-    }
-}
-
-/*
- * Assign the typevalue "tv" to the variable or variables at "arg_start".
- * Handles both "var" with any type and "[var, var; var]" with a list type.
- * When "op" is not NULL it points to a string with characters that
- * must appear after the variable(s).  Use "+", "-" or "." for add, subtract
- * or concatenate.
- * Returns OK or FAIL;
- */
-    static int
-ex_let_vars(
-    char_u	*arg_start,
-    typval_T	*tv,
-    int		copy,		// copy values from "tv", don't move
-    int		semicolon,	// from skip_var_list()
-    int		var_count,	// from skip_var_list()
-    int		is_const,	// lock variables for const
-    char_u	*op)
-{
-    char_u	*arg = arg_start;
-    list_T	*l;
-    int		i;
-    listitem_T	*item;
-    typval_T	ltv;
-
-    if (*arg != '[')
-    {
-	/*
-	 * ":let var = expr" or ":for var in list"
-	 */
-	if (ex_let_one(arg, tv, copy, is_const, op, op) == NULL)
-	    return FAIL;
-	return OK;
-    }
-
-    /*
-     * ":let [v1, v2] = list" or ":for [v1, v2] in listlist"
-     */
-    if (tv->v_type != VAR_LIST || (l = tv->vval.v_list) == NULL)
-    {
-	emsg(_(e_listreq));
-	return FAIL;
-    }
-
-    i = list_len(l);
-    if (semicolon == 0 && var_count < i)
-    {
-	emsg(_("E687: Less targets than List items"));
-	return FAIL;
-    }
-    if (var_count - semicolon > i)
-    {
-	emsg(_("E688: More targets than List items"));
-	return FAIL;
-    }
-
-    item = l->lv_first;
-    while (*arg != ']')
-    {
-	arg = skipwhite(arg + 1);
-	arg = ex_let_one(arg, &item->li_tv, TRUE, is_const,
-							  (char_u *)",;]", op);
-	item = item->li_next;
-	if (arg == NULL)
-	    return FAIL;
-
-	arg = skipwhite(arg);
-	if (*arg == ';')
-	{
-	    /* Put the rest of the list (may be empty) in the var after ';'.
-	     * Create a new list for this. */
-	    l = list_alloc();
-	    if (l == NULL)
-		return FAIL;
-	    while (item != NULL)
-	    {
-		list_append_tv(l, &item->li_tv);
-		item = item->li_next;
-	    }
-
-	    ltv.v_type = VAR_LIST;
-	    ltv.v_lock = 0;
-	    ltv.vval.v_list = l;
-	    l->lv_refcount = 1;
-
-	    arg = ex_let_one(skipwhite(arg + 1), &ltv, FALSE, is_const,
-							    (char_u *)"]", op);
-	    clear_tv(&ltv);
-	    if (arg == NULL)
-		return FAIL;
-	    break;
-	}
-	else if (*arg != ',' && *arg != ']')
-	{
-	    internal_error("ex_let_vars()");
-	    return FAIL;
-	}
-    }
-
-    return OK;
-}
-
-/*
- * Skip over assignable variable "var" or list of variables "[var, var]".
- * Used for ":let varvar = expr" and ":for varvar in expr".
- * For "[var, var]" increment "*var_count" for each variable.
- * for "[var, var; var]" set "semicolon".
- * Return NULL for an error.
- */
-    static char_u *
-skip_var_list(
-    char_u	*arg,
-    int		*var_count,
-    int		*semicolon)
-{
-    char_u	*p, *s;
-
-    if (*arg == '[')
-    {
-	/* "[var, var]": find the matching ']'. */
-	p = arg;
-	for (;;)
-	{
-	    p = skipwhite(p + 1);	/* skip whites after '[', ';' or ',' */
-	    s = skip_var_one(p);
-	    if (s == p)
-	    {
-		semsg(_(e_invarg2), p);
-		return NULL;
-	    }
-	    ++*var_count;
-
-	    p = skipwhite(s);
-	    if (*p == ']')
-		break;
-	    else if (*p == ';')
-	    {
-		if (*semicolon == 1)
-		{
-		    emsg(_("Double ; in list of variables"));
-		    return NULL;
-		}
-		*semicolon = 1;
-	    }
-	    else if (*p != ',')
-	    {
-		semsg(_(e_invarg2), p);
-		return NULL;
-	    }
-	}
-	return p + 1;
-    }
-    else
-	return skip_var_one(arg);
-}
-
-/*
- * Skip one (assignable) variable name, including @r, $VAR, &option, d.key,
- * l[idx].
- */
-    static char_u *
-skip_var_one(char_u *arg)
-{
-    if (*arg == '@' && arg[1] != NUL)
-	return arg + 2;
-    return find_name_end(*arg == '$' || *arg == '&' ? arg + 1 : arg,
-				   NULL, NULL, FNE_INCL_BR | FNE_CHECK_START);
-}
-
-/*
- * List variables for hashtab "ht" with prefix "prefix".
- * If "empty" is TRUE also list NULL strings as empty strings.
- */
-    void
-list_hashtable_vars(
-    hashtab_T	*ht,
-    char	*prefix,
-    int		empty,
-    int		*first)
-{
-    hashitem_T	*hi;
-    dictitem_T	*di;
-    int		todo;
-    char_u	buf[IOSIZE];
-
-    todo = (int)ht->ht_used;
-    for (hi = ht->ht_array; todo > 0 && !got_int; ++hi)
-    {
-	if (!HASHITEM_EMPTY(hi))
-	{
-	    --todo;
-	    di = HI2DI(hi);
-
-	    // apply :filter /pat/ to variable name
-	    vim_strncpy((char_u *)buf, (char_u *)prefix, IOSIZE - 1);
-	    vim_strcat((char_u *)buf, di->di_key, IOSIZE);
-	    if (message_filtered(buf))
-		continue;
-
-	    if (empty || di->di_tv.v_type != VAR_STRING
-					   || di->di_tv.vval.v_string != NULL)
-		list_one_var(di, prefix, first);
-	}
-    }
-}
-
-/*
- * List global variables.
- */
-    static void
-list_glob_vars(int *first)
-{
-    list_hashtable_vars(&globvarht, "", TRUE, first);
-}
-
-/*
- * List buffer variables.
- */
-    static void
-list_buf_vars(int *first)
-{
-    list_hashtable_vars(&curbuf->b_vars->dv_hashtab, "b:", TRUE, first);
-}
-
-/*
- * List window variables.
- */
-    static void
-list_win_vars(int *first)
-{
-    list_hashtable_vars(&curwin->w_vars->dv_hashtab, "w:", TRUE, first);
-}
-
-/*
- * List tab page variables.
- */
-    static void
-list_tab_vars(int *first)
-{
-    list_hashtable_vars(&curtab->tp_vars->dv_hashtab, "t:", TRUE, first);
-}
-
-/*
- * List Vim variables.
- */
-    static void
-list_vim_vars(int *first)
-{
-    list_hashtable_vars(&vimvarht, "v:", FALSE, first);
-}
-
-/*
- * List script-local variables, if there is a script.
- */
-    static void
-list_script_vars(int *first)
-{
-    if (current_sctx.sc_sid > 0 && current_sctx.sc_sid <= ga_scripts.ga_len)
-	list_hashtable_vars(&SCRIPT_VARS(current_sctx.sc_sid),
-							   "s:", FALSE, first);
-}
-
-/*
- * List variables in "arg".
- */
-    static char_u *
-list_arg_vars(exarg_T *eap, char_u *arg, int *first)
-{
-    int		error = FALSE;
-    int		len;
-    char_u	*name;
-    char_u	*name_start;
-    char_u	*arg_subsc;
-    char_u	*tofree;
-    typval_T    tv;
-
-    while (!ends_excmd(*arg) && !got_int)
-    {
-	if (error || eap->skip)
-	{
-	    arg = find_name_end(arg, NULL, NULL, FNE_INCL_BR | FNE_CHECK_START);
-	    if (!VIM_ISWHITE(*arg) && !ends_excmd(*arg))
-	    {
-		emsg_severe = TRUE;
-		emsg(_(e_trailing));
-		break;
-	    }
-	}
-	else
-	{
-	    /* get_name_len() takes care of expanding curly braces */
-	    name_start = name = arg;
-	    len = get_name_len(&arg, &tofree, TRUE, TRUE);
-	    if (len <= 0)
-	    {
-		/* This is mainly to keep test 49 working: when expanding
-		 * curly braces fails overrule the exception error message. */
-		if (len < 0 && !aborting())
-		{
-		    emsg_severe = TRUE;
-		    semsg(_(e_invarg2), arg);
-		    break;
-		}
-		error = TRUE;
-	    }
-	    else
-	    {
-		if (tofree != NULL)
-		    name = tofree;
-		if (get_var_tv(name, len, &tv, NULL, TRUE, FALSE) == FAIL)
-		    error = TRUE;
-		else
-		{
-		    /* handle d.key, l[idx], f(expr) */
-		    arg_subsc = arg;
-		    if (handle_subscript(&arg, &tv, TRUE, TRUE,
-							  name, &name) == FAIL)
-			error = TRUE;
-		    else
-		    {
-			if (arg == arg_subsc && len == 2 && name[1] == ':')
-			{
-			    switch (*name)
-			    {
-				case 'g': list_glob_vars(first); break;
-				case 'b': list_buf_vars(first); break;
-				case 'w': list_win_vars(first); break;
-				case 't': list_tab_vars(first); break;
-				case 'v': list_vim_vars(first); break;
-				case 's': list_script_vars(first); break;
-				case 'l': list_func_vars(first); break;
-				default:
-					  semsg(_("E738: Can't list variables for %s"), name);
-			    }
-			}
-			else
-			{
-			    char_u	numbuf[NUMBUFLEN];
-			    char_u	*tf;
-			    int		c;
-			    char_u	*s;
-
-			    s = echo_string(&tv, &tf, numbuf, 0);
-			    c = *arg;
-			    *arg = NUL;
-			    list_one_var_a("",
-				    arg == arg_subsc ? name : name_start,
-				    tv.v_type,
-				    s == NULL ? (char_u *)"" : s,
-				    first);
-			    *arg = c;
-			    vim_free(tf);
-			}
-			clear_tv(&tv);
-		    }
-		}
-	    }
-
-	    vim_free(tofree);
-	}
-
-	arg = skipwhite(arg);
-    }
-
-    return arg;
-}
-
-/*
- * Set one item of ":let var = expr" or ":let [v1, v2] = list" to its value.
- * Returns a pointer to the char just after the var name.
- * Returns NULL if there is an error.
- */
-    static char_u *
-ex_let_one(
-    char_u	*arg,		// points to variable name
-    typval_T	*tv,		// value to assign to variable
-    int		copy,		// copy value from "tv"
-    int		is_const,	// lock variable for const
-    char_u	*endchars,	// valid chars after variable name  or NULL
-    char_u	*op)		// "+", "-", "."  or NULL
-{
-    int		c1;
-    char_u	*name;
-    char_u	*p;
-    char_u	*arg_end = NULL;
-    int		len;
-    int		opt_flags;
-    char_u	*tofree = NULL;
-
-    /*
-     * ":let $VAR = expr": Set environment variable.
-     */
-    if (*arg == '$')
-    {
-	if (is_const)
-	{
-	    emsg(_("E996: Cannot lock an environment variable"));
-	    return NULL;
-	}
-	/* Find the end of the name. */
-	++arg;
-	name = arg;
-	len = get_env_len(&arg);
-	if (len == 0)
-	    semsg(_(e_invarg2), name - 1);
-	else
-	{
-	    if (op != NULL && vim_strchr((char_u *)"+-*/%", *op) != NULL)
-		semsg(_(e_letwrong), op);
-	    else if (endchars != NULL
-			     && vim_strchr(endchars, *skipwhite(arg)) == NULL)
-		emsg(_(e_letunexp));
-	    else if (!check_secure())
-	    {
-		c1 = name[len];
-		name[len] = NUL;
-		p = tv_get_string_chk(tv);
-		if (p != NULL && op != NULL && *op == '.')
-		{
-		    int	    mustfree = FALSE;
-		    char_u  *s = vim_getenv(name, &mustfree);
-
-		    if (s != NULL)
-		    {
-			p = tofree = concat_str(s, p);
-			if (mustfree)
-			    vim_free(s);
-		    }
-		}
-		if (p != NULL)
-		{
-		    vim_setenv(name, p);
-		    if (STRICMP(name, "HOME") == 0)
-			init_homedir();
-		    else if (didset_vim && STRICMP(name, "VIM") == 0)
-			didset_vim = FALSE;
-		    else if (didset_vimruntime
-					&& STRICMP(name, "VIMRUNTIME") == 0)
-			didset_vimruntime = FALSE;
-		    arg_end = arg;
-		}
-		name[len] = c1;
-		vim_free(tofree);
-	    }
-	}
-    }
-
-    /*
-     * ":let &option = expr": Set option value.
-     * ":let &l:option = expr": Set local option value.
-     * ":let &g:option = expr": Set global option value.
-     */
-    else if (*arg == '&')
-    {
-	if (is_const)
-	{
-	    emsg(_("E996: Cannot lock an option"));
-	    return NULL;
-	}
-	/* Find the end of the name. */
-	p = find_option_end(&arg, &opt_flags);
-	if (p == NULL || (endchars != NULL
-			      && vim_strchr(endchars, *skipwhite(p)) == NULL))
-	    emsg(_(e_letunexp));
-	else
-	{
-	    long	n;
-	    int		opt_type;
-	    long	numval;
-	    char_u	*stringval = NULL;
-	    char_u	*s;
-
-	    c1 = *p;
-	    *p = NUL;
-
-	    n = (long)tv_get_number(tv);
-	    s = tv_get_string_chk(tv);	    /* != NULL if number or string */
-	    if (s != NULL && op != NULL && *op != '=')
-	    {
-		opt_type = get_option_value(arg, &numval,
-						       &stringval, opt_flags);
-		if ((opt_type == 1 && *op == '.')
-			|| (opt_type == 0 && *op != '.'))
-		{
-		    semsg(_(e_letwrong), op);
-		    s = NULL;  // don't set the value
-		}
-		else
-		{
-		    if (opt_type == 1)  // number
-		    {
-			switch (*op)
-			{
-			    case '+': n = numval + n; break;
-			    case '-': n = numval - n; break;
-			    case '*': n = numval * n; break;
-			    case '/': n = (long)num_divide(numval, n); break;
-			    case '%': n = (long)num_modulus(numval, n); break;
-			}
-		    }
-		    else if (opt_type == 0 && stringval != NULL) // string
-		    {
-			s = concat_str(stringval, s);
-			vim_free(stringval);
-			stringval = s;
-		    }
-		}
-	    }
-	    if (s != NULL)
-	    {
-		set_option_value(arg, n, s, opt_flags);
-		arg_end = p;
-	    }
-	    *p = c1;
-	    vim_free(stringval);
-	}
-    }
-
-    /*
-     * ":let @r = expr": Set register contents.
-     */
-    else if (*arg == '@')
-    {
-	if (is_const)
-	{
-	    emsg(_("E996: Cannot lock a register"));
-	    return NULL;
-	}
-	++arg;
-	if (op != NULL && vim_strchr((char_u *)"+-*/%", *op) != NULL)
-	    semsg(_(e_letwrong), op);
-	else if (endchars != NULL
-			 && vim_strchr(endchars, *skipwhite(arg + 1)) == NULL)
-	    emsg(_(e_letunexp));
-	else
-	{
-	    char_u	*ptofree = NULL;
-	    char_u	*s;
-
-	    p = tv_get_string_chk(tv);
-	    if (p != NULL && op != NULL && *op == '.')
-	    {
-		s = get_reg_contents(*arg == '@' ? '"' : *arg, GREG_EXPR_SRC);
-		if (s != NULL)
-		{
-		    p = ptofree = concat_str(s, p);
-		    vim_free(s);
-		}
-	    }
-	    if (p != NULL)
-	    {
-		write_reg_contents(*arg == '@' ? '"' : *arg, p, -1, FALSE);
-		arg_end = arg + 1;
-	    }
-	    vim_free(ptofree);
-	}
-    }
-
-    /*
-     * ":let var = expr": Set internal variable.
-     * ":let {expr} = expr": Idem, name made with curly braces
-     */
-    else if (eval_isnamec1(*arg) || *arg == '{')
-    {
-	lval_T	lv;
-
-	p = get_lval(arg, tv, &lv, FALSE, FALSE, 0, FNE_CHECK_START);
-	if (p != NULL && lv.ll_name != NULL)
-	{
-	    if (endchars != NULL && vim_strchr(endchars, *skipwhite(p)) == NULL)
-		emsg(_(e_letunexp));
-	    else
-	    {
-		set_var_lval(&lv, p, tv, copy, is_const, op);
-		arg_end = p;
-	    }
-	}
-	clear_lval(&lv);
-    }
-
-    else
-	semsg(_(e_invarg2), arg);
-
-    return arg_end;
-}
-
-/*
  * Get an lval: variable, Dict item or List item that can be assigned a value
  * to: "name", "na{me}", "name[expr]", "name[expr:expr]", "name[expr][expr]",
  * "name.key", "name.key[expr]" etc.
@@ -2502,7 +1658,7 @@ clear_lval(lval_T *lp)
  * "op" is NULL, "+" for "+=", "-" for "-=", "*" for "*=", "/" for "/=",
  * "%" for "%=", "." for ".=" or "=" for "=".
  */
-    static void
+    void
 set_var_lval(
     lval_T	*lp,
     char_u	*endp,
@@ -3105,378 +2261,6 @@ set_context_for_expression(
     xp->xp_pattern = arg;
 }
 
-/*
- * ":unlet[!] var1 ... " command.
- */
-    void
-ex_unlet(exarg_T *eap)
-{
-    ex_unletlock(eap, eap->arg, 0);
-}
-
-/*
- * ":lockvar" and ":unlockvar" commands
- */
-    void
-ex_lockvar(exarg_T *eap)
-{
-    char_u	*arg = eap->arg;
-    int		deep = 2;
-
-    if (eap->forceit)
-	deep = -1;
-    else if (vim_isdigit(*arg))
-    {
-	deep = getdigits(&arg);
-	arg = skipwhite(arg);
-    }
-
-    ex_unletlock(eap, arg, deep);
-}
-
-/*
- * ":unlet", ":lockvar" and ":unlockvar" are quite similar.
- */
-    static void
-ex_unletlock(
-    exarg_T	*eap,
-    char_u	*argstart,
-    int		deep)
-{
-    char_u	*arg = argstart;
-    char_u	*name_end;
-    int		error = FALSE;
-    lval_T	lv;
-
-    do
-    {
-	if (*arg == '$')
-	{
-	    char_u    *name = ++arg;
-
-	    if (get_env_len(&arg) == 0)
-	    {
-		semsg(_(e_invarg2), name - 1);
-		return;
-	    }
-	    vim_unsetenv(name);
-	    arg = skipwhite(arg);
-	    continue;
-	}
-
-	/* Parse the name and find the end. */
-	name_end = get_lval(arg, NULL, &lv, TRUE, eap->skip || error, 0,
-							     FNE_CHECK_START);
-	if (lv.ll_name == NULL)
-	    error = TRUE;	    /* error but continue parsing */
-	if (name_end == NULL || (!VIM_ISWHITE(*name_end)
-						   && !ends_excmd(*name_end)))
-	{
-	    if (name_end != NULL)
-	    {
-		emsg_severe = TRUE;
-		emsg(_(e_trailing));
-	    }
-	    if (!(eap->skip || error))
-		clear_lval(&lv);
-	    break;
-	}
-
-	if (!error && !eap->skip)
-	{
-	    if (eap->cmdidx == CMD_unlet)
-	    {
-		if (do_unlet_var(&lv, name_end, eap->forceit) == FAIL)
-		    error = TRUE;
-	    }
-	    else
-	    {
-		if (do_lock_var(&lv, name_end, deep,
-					  eap->cmdidx == CMD_lockvar) == FAIL)
-		    error = TRUE;
-	    }
-	}
-
-	if (!eap->skip)
-	    clear_lval(&lv);
-
-	arg = skipwhite(name_end);
-    } while (!ends_excmd(*arg));
-
-    eap->nextcmd = check_nextcmd(arg);
-}
-
-    static int
-do_unlet_var(
-    lval_T	*lp,
-    char_u	*name_end,
-    int		forceit)
-{
-    int		ret = OK;
-    int		cc;
-
-    if (lp->ll_tv == NULL)
-    {
-	cc = *name_end;
-	*name_end = NUL;
-
-	/* Normal name or expanded name. */
-	if (do_unlet(lp->ll_name, forceit) == FAIL)
-	    ret = FAIL;
-	*name_end = cc;
-    }
-    else if ((lp->ll_list != NULL
-		 && var_check_lock(lp->ll_list->lv_lock, lp->ll_name, FALSE))
-	    || (lp->ll_dict != NULL
-		 && var_check_lock(lp->ll_dict->dv_lock, lp->ll_name, FALSE)))
-	return FAIL;
-    else if (lp->ll_range)
-    {
-	listitem_T    *li;
-	listitem_T    *ll_li = lp->ll_li;
-	int	      ll_n1 = lp->ll_n1;
-
-	while (ll_li != NULL && (lp->ll_empty2 || lp->ll_n2 >= ll_n1))
-	{
-	    li = ll_li->li_next;
-	    if (var_check_lock(ll_li->li_tv.v_lock, lp->ll_name, FALSE))
-		return FAIL;
-	    ll_li = li;
-	    ++ll_n1;
-	}
-
-	/* Delete a range of List items. */
-	while (lp->ll_li != NULL && (lp->ll_empty2 || lp->ll_n2 >= lp->ll_n1))
-	{
-	    li = lp->ll_li->li_next;
-	    listitem_remove(lp->ll_list, lp->ll_li);
-	    lp->ll_li = li;
-	    ++lp->ll_n1;
-	}
-    }
-    else
-    {
-	if (lp->ll_list != NULL)
-	    /* unlet a List item. */
-	    listitem_remove(lp->ll_list, lp->ll_li);
-	else
-	    /* unlet a Dictionary item. */
-	    dictitem_remove(lp->ll_dict, lp->ll_di);
-    }
-
-    return ret;
-}
-
-/*
- * "unlet" a variable.  Return OK if it existed, FAIL if not.
- * When "forceit" is TRUE don't complain if the variable doesn't exist.
- */
-    int
-do_unlet(char_u *name, int forceit)
-{
-    hashtab_T	*ht;
-    hashitem_T	*hi;
-    char_u	*varname;
-    dict_T	*d;
-    dictitem_T	*di;
-
-    ht = find_var_ht(name, &varname);
-    if (ht != NULL && *varname != NUL)
-    {
-	d = get_current_funccal_dict(ht);
-	if (d == NULL)
-	{
-	    if (ht == &globvarht)
-		d = &globvardict;
-	    else if (ht == &compat_hashtab)
-		d = &vimvardict;
-	    else
-	    {
-		di = find_var_in_ht(ht, *name, (char_u *)"", FALSE);
-		d = di == NULL ? NULL : di->di_tv.vval.v_dict;
-	    }
-	    if (d == NULL)
-	    {
-		internal_error("do_unlet()");
-		return FAIL;
-	    }
-	}
-	hi = hash_find(ht, varname);
-	if (HASHITEM_EMPTY(hi))
-	    hi = find_hi_in_scoped_ht(name, &ht);
-	if (hi != NULL && !HASHITEM_EMPTY(hi))
-	{
-	    di = HI2DI(hi);
-	    if (var_check_fixed(di->di_flags, name, FALSE)
-		    || var_check_ro(di->di_flags, name, FALSE)
-		    || var_check_lock(d->dv_lock, name, FALSE))
-		return FAIL;
-
-	    delete_var(ht, hi);
-	    return OK;
-	}
-    }
-    if (forceit)
-	return OK;
-    semsg(_("E108: No such variable: \"%s\""), name);
-    return FAIL;
-}
-
-/*
- * Lock or unlock variable indicated by "lp".
- * "deep" is the levels to go (-1 for unlimited);
- * "lock" is TRUE for ":lockvar", FALSE for ":unlockvar".
- */
-    static int
-do_lock_var(
-    lval_T	*lp,
-    char_u	*name_end,
-    int		deep,
-    int		lock)
-{
-    int		ret = OK;
-    int		cc;
-    dictitem_T	*di;
-
-    if (deep == 0)	/* nothing to do */
-	return OK;
-
-    if (lp->ll_tv == NULL)
-    {
-	cc = *name_end;
-	*name_end = NUL;
-
-	/* Normal name or expanded name. */
-	di = find_var(lp->ll_name, NULL, TRUE);
-	if (di == NULL)
-	    ret = FAIL;
-	else if ((di->di_flags & DI_FLAGS_FIX)
-			&& di->di_tv.v_type != VAR_DICT
-			&& di->di_tv.v_type != VAR_LIST)
-	    /* For historic reasons this error is not given for a list or dict.
-	     * E.g., the b: dict could be locked/unlocked. */
-	    semsg(_("E940: Cannot lock or unlock variable %s"), lp->ll_name);
-	else
-	{
-	    if (lock)
-		di->di_flags |= DI_FLAGS_LOCK;
-	    else
-		di->di_flags &= ~DI_FLAGS_LOCK;