# HG changeset patch
# User Bram Moolenaar <Bram@vim.org>
# Date 1625945404 -7200
# Node ID dc66d0284518dd5efea84ad65a695fd8a1f51a68
# Parent  362cabc968e832b31029250243e679c9e0546345
patch 8.2.3139: functions for string manipulation are spread out

Commit: https://github.com/vim/vim/commit/a2438132a675be4dde3acbdf03ba1fdb2f09427c
Author: Yegappan Lakshmanan <yegappan@yahoo.com>
Date:   Sat Jul 10 21:29:18 2021 +0200

    patch 8.2.3139: functions for string manipulation are spread out

    Problem:    Functions for string manipulation are spread out.
    Solution:   Move string related functions to a new source file. (Yegappan
                Lakshmanan, closes #8470)

diff --git a/Filelist b/Filelist
--- a/Filelist
+++ b/Filelist
@@ -134,6 +134,7 @@ SRC_ALL =	\
 		src/spell.h \
 		src/spellfile.c \
 		src/spellsuggest.c \
+		src/strings.c \
 		src/structs.h \
 		src/syntax.c \
 		src/tag.c \
@@ -296,6 +297,7 @@ SRC_ALL =	\
 		src/proto/spell.pro \
 		src/proto/spellfile.pro \
 		src/proto/spellsuggest.pro \
+		src/proto/strings.pro \
 		src/proto/syntax.pro \
 		src/proto/tag.pro \
 		src/proto/term.pro \
diff --git a/src/Make_ami.mak b/src/Make_ami.mak
--- a/src/Make_ami.mak
+++ b/src/Make_ami.mak
@@ -162,6 +162,7 @@ SRC += \
 	spell.c \
 	spellfile.c \
 	spellsuggest.c \
+	strings.c \
 	syntax.c \
 	tag.c \
 	term.c \
diff --git a/src/Make_cyg_ming.mak b/src/Make_cyg_ming.mak
--- a/src/Make_cyg_ming.mak
+++ b/src/Make_cyg_ming.mak
@@ -809,6 +809,7 @@ OBJ = \
 	$(OUTDIR)/spell.o \
 	$(OUTDIR)/spellfile.o \
 	$(OUTDIR)/spellsuggest.o \
+	$(OUTDIR)/strings.o \
 	$(OUTDIR)/syntax.o \
 	$(OUTDIR)/tag.o \
 	$(OUTDIR)/term.o \
diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -819,6 +819,7 @@ OBJ = \
 	$(OUTDIR)\spell.obj \
 	$(OUTDIR)\spellfile.obj \
 	$(OUTDIR)\spellsuggest.obj \
+	$(OUTDIR)\strings.obj \
 	$(OUTDIR)\syntax.obj \
 	$(OUTDIR)\tag.obj \
 	$(OUTDIR)\term.obj \
@@ -1792,6 +1793,8 @@ lib$(MZSCHEME_MAIN_LIB)$(MZSCHEME_VER).l
 
 $(OUTDIR)/spellsuggest.obj:	$(OUTDIR) spellsuggest.c  $(INCL)
 
+$(OUTDIR)/strings.obj:	$(OUTDIR) strings.c  $(INCL)
+
 $(OUTDIR)/syntax.obj:	$(OUTDIR) syntax.c  $(INCL)
 
 $(OUTDIR)/tag.obj:	$(OUTDIR) tag.c  $(INCL)
@@ -2012,6 +2015,7 @@ proto.h: \
 	proto/spell.pro \
 	proto/spellfile.pro \
 	proto/spellsuggest.pro \
+	proto/strings.pro \
 	proto/syntax.pro \
 	proto/tag.pro \
 	proto/term.pro \
diff --git a/src/Make_vms.mms b/src/Make_vms.mms
--- a/src/Make_vms.mms
+++ b/src/Make_vms.mms
@@ -393,6 +393,7 @@ SRC = \
 	spell.c \
 	spellfile.c \
 	spellsuggest.c \
+	strings.c \
 	syntax.c \
 	tag.c \
 	term.c \
@@ -512,6 +513,7 @@ OBJ = \
 	spell.obj \
 	spellfile.obj \
 	spellsuggest.obj \
+	strings.obj \
 	syntax.obj \
 	tag.obj \
 	term.obj \
@@ -1048,6 +1050,10 @@ spellsuggest.obj : spellsuggest.c vim.h 
  ascii.h keymap.h term.h macros.h option.h structs.h \
  regexp.h gui.h beval.h [.proto]gui_beval.pro alloc.h ex_cmds.h spell.h \
  proto.h errors.h globals.h
+strings.obj : strings.c vim.h [.auto]config.h feature.h os_unix.h \
+ ascii.h keymap.h term.h macros.h option.h structs.h \
+ regexp.h gui.h beval.h [.proto]gui_beval.pro alloc.h ex_cmds.h spell.h \
+ proto.h errors.h globals.h
 syntax.obj : syntax.c vim.h [.auto]config.h feature.h os_unix.h \
  ascii.h keymap.h term.h macros.h structs.h regexp.h \
  gui.h beval.h [.proto]gui_beval.pro option.h ex_cmds.h proto.h \
diff --git a/src/Makefile b/src/Makefile
--- a/src/Makefile
+++ b/src/Makefile
@@ -1677,6 +1677,7 @@ BASIC_SRC = \
 	spell.c \
 	spellfile.c \
 	spellsuggest.c \
+	strings.c \
 	syntax.c \
 	tag.c \
 	term.c \
@@ -1828,6 +1829,7 @@ OBJ_COMMON = \
 	objects/spell.o \
 	objects/spellfile.o \
 	objects/spellsuggest.o \
+	objects/strings.o \
 	objects/syntax.o \
 	objects/tag.o \
 	objects/term.o \
@@ -2011,6 +2013,7 @@ PRO_AUTO = \
 	spell.pro \
 	spellfile.pro \
 	spellsuggest.pro \
+	strings.pro \
 	syntax.pro \
 	tag.pro \
 	term.pro \
@@ -3516,6 +3519,9 @@ objects/spellfile.o: spellfile.c
 objects/spellsuggest.o: spellsuggest.c
 	$(CCC) -o $@ spellsuggest.c
 
+objects/strings.o: strings.c
+	$(CCC) -o $@ strings.c
+
 objects/syntax.o: syntax.c
 	$(CCC) -o $@ syntax.c
 
@@ -4049,6 +4055,10 @@ objects/spellsuggest.o: spellsuggest.c v
  os_unix.h auto/osdef.h ascii.h keymap.h term.h macros.h option.h beval.h \
  proto/gui_beval.pro structs.h regexp.h gui.h alloc.h ex_cmds.h spell.h \
  proto.h errors.h globals.h
+objects/strings.o: strings.c vim.h protodef.h auto/config.h feature.h os_unix.h \
+ auto/osdef.h ascii.h keymap.h term.h macros.h option.h beval.h \
+ proto/gui_beval.pro structs.h regexp.h gui.h alloc.h ex_cmds.h spell.h \
+ proto.h errors.h globals.h
 objects/syntax.o: syntax.c vim.h protodef.h auto/config.h feature.h os_unix.h \
  auto/osdef.h ascii.h keymap.h term.h macros.h option.h beval.h \
  proto/gui_beval.pro structs.h regexp.h gui.h alloc.h ex_cmds.h spell.h \
diff --git a/src/README.md b/src/README.md
--- a/src/README.md
+++ b/src/README.md
@@ -80,6 +80,7 @@ sign.c		| signs
 spell.c		| spell checking core
 spellfile.c	| spell file handling
 spellsuggest.c	| spell correction suggestions
+strings.c	| string manipulation functions
 syntax.c	| syntax and other highlighting
 tag.c		| tags
 term.c		| terminal handling, termcap codes
diff --git a/src/eval.c b/src/eval.c
--- a/src/eval.c
+++ b/src/eval.c
@@ -57,6 +57,7 @@ static int eval7_leader(typval_T *rettv,
 
 static int free_unref_items(int copyID);
 static char_u *make_expanded_name(char_u *in_start, char_u *expr_start, char_u *expr_end, char_u *in_end);
+static char_u *eval_next_line(evalarg_T *evalarg);
 
 /*
  * Return "n1" divided by "n2", taking care of dividing by zero.
@@ -2113,7 +2114,7 @@ getline_peek_skip_comments(evalarg_T *ev
  * FALSE.
  * "arg" must point somewhere inside a line, not at the start.
  */
-    char_u *
+    static char_u *
 eval_next_non_blank(char_u *arg, evalarg_T *evalarg, int *getnext)
 {
     char_u *p = skipwhite(arg);
@@ -2144,7 +2145,7 @@ eval_next_non_blank(char_u *arg, evalarg
  * To be called after eval_next_non_blank() sets "getnext" to TRUE.
  * Only called for Vim9 script.
  */
-    char_u *
+    static char_u *
 eval_next_line(evalarg_T *evalarg)
 {
     garray_T	*gap = &evalarg->eval_ga;
@@ -5172,50 +5173,6 @@ echo_string(
 }
 
 /*
- * Return string "str" in ' quotes, doubling ' characters.
- * If "str" is NULL an empty string is assumed.
- * If "function" is TRUE make it function('string').
- */
-    char_u *
-string_quote(char_u *str, int function)
-{
-    unsigned	len;
-    char_u	*p, *r, *s;
-
-    len = (function ? 13 : 3);
-    if (str != NULL)
-    {
-	len += (unsigned)STRLEN(str);
-	for (p = str; *p != NUL; MB_PTR_ADV(p))
-	    if (*p == '\'')
-		++len;
-    }
-    s = r = alloc(len);
-    if (r != NULL)
-    {
-	if (function)
-	{
-	    STRCPY(r, "function('");
-	    r += 10;
-	}
-	else
-	    *r++ = '\'';
-	if (str != NULL)
-	    for (p = str; *p != NUL; )
-	    {
-		if (*p == '\'')
-		    *r++ = '\'';
-		MB_COPY_CHAR(p, r);
-	    }
-	*r++ = '\'';
-	if (function)
-	    *r++ = ')';
-	*r++ = NUL;
-    }
-    return s;
-}
-
-/*
  * Convert the specified byte index of line 'lnum' in buffer 'buf' to a
  * character index.  Works only for loaded buffers. Returns -1 on failure.
  * The index of the first byte and the first character is zero.
diff --git a/src/evalfunc.c b/src/evalfunc.c
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -29,14 +29,10 @@ static void f_balloon_split(typval_T *ar
 # endif
 #endif
 static void f_byte2line(typval_T *argvars, typval_T *rettv);
-static void byteidx(typval_T *argvars, typval_T *rettv, int comp);
-static void f_byteidx(typval_T *argvars, typval_T *rettv);
-static void f_byteidxcomp(typval_T *argvars, typval_T *rettv);
 static void f_call(typval_T *argvars, typval_T *rettv);
 static void f_changenr(typval_T *argvars, typval_T *rettv);
 static void f_char2nr(typval_T *argvars, typval_T *rettv);
 static void f_charcol(typval_T *argvars, typval_T *rettv);
-static void f_charidx(typval_T *argvars, typval_T *rettv);
 static void f_col(typval_T *argvars, typval_T *rettv);
 static void f_confirm(typval_T *argvars, typval_T *rettv);
 static void f_copy(typval_T *argvars, typval_T *rettv);
@@ -83,7 +79,6 @@ static void f_hasmapto(typval_T *argvars
 static void f_hlID(typval_T *argvars, typval_T *rettv);
 static void f_hlexists(typval_T *argvars, typval_T *rettv);
 static void f_hostname(typval_T *argvars, typval_T *rettv);
-static void f_iconv(typval_T *argvars, typval_T *rettv);
 static void f_index(typval_T *argvars, typval_T *rettv);
 static void f_input(typval_T *argvars, typval_T *rettv);
 static void f_inputdialog(typval_T *argvars, typval_T *rettv);
@@ -173,19 +168,6 @@ static void f_spellbadword(typval_T *arg
 static void f_spellsuggest(typval_T *argvars, typval_T *rettv);
 static void f_split(typval_T *argvars, typval_T *rettv);
 static void f_srand(typval_T *argvars, typval_T *rettv);
-static void f_str2list(typval_T *argvars, typval_T *rettv);
-static void f_str2nr(typval_T *argvars, typval_T *rettv);
-static void f_strcharlen(typval_T *argvars, typval_T *rettv);
-static void f_strchars(typval_T *argvars, typval_T *rettv);
-static void f_strgetchar(typval_T *argvars, typval_T *rettv);
-static void f_stridx(typval_T *argvars, typval_T *rettv);
-static void f_strlen(typval_T *argvars, typval_T *rettv);
-static void f_strcharpart(typval_T *argvars, typval_T *rettv);
-static void f_strpart(typval_T *argvars, typval_T *rettv);
-static void f_strridx(typval_T *argvars, typval_T *rettv);
-static void f_strtrans(typval_T *argvars, typval_T *rettv);
-static void f_strdisplaywidth(typval_T *argvars, typval_T *rettv);
-static void f_strwidth(typval_T *argvars, typval_T *rettv);
 static void f_submatch(typval_T *argvars, typval_T *rettv);
 static void f_substitute(typval_T *argvars, typval_T *rettv);
 static void f_swapinfo(typval_T *argvars, typval_T *rettv);
@@ -198,10 +180,6 @@ static void f_synconcealed(typval_T *arg
 static void f_tabpagebuflist(typval_T *argvars, typval_T *rettv);
 static void f_taglist(typval_T *argvars, typval_T *rettv);
 static void f_tagfiles(typval_T *argvars, typval_T *rettv);
-static void f_tolower(typval_T *argvars, typval_T *rettv);
-static void f_toupper(typval_T *argvars, typval_T *rettv);
-static void f_tr(typval_T *argvars, typval_T *rettv);
-static void f_trim(typval_T *argvars, typval_T *rettv);
 static void f_type(typval_T *argvars, typval_T *rettv);
 static void f_virtcol(typval_T *argvars, typval_T *rettv);
 static void f_visualmode(typval_T *argvars, typval_T *rettv);
@@ -2377,50 +2355,6 @@ f_byte2line(typval_T *argvars UNUSED, ty
 #endif
 }
 
-    static void
-byteidx(typval_T *argvars, typval_T *rettv, int comp UNUSED)
-{
-    char_u	*t;
-    char_u	*str;
-    varnumber_T	idx;
-
-    str = tv_get_string_chk(&argvars[0]);
-    idx = tv_get_number_chk(&argvars[1], NULL);
-    rettv->vval.v_number = -1;
-    if (str == NULL || idx < 0)
-	return;
-
-    t = str;
-    for ( ; idx > 0; idx--)
-    {
-	if (*t == NUL)		// EOL reached
-	    return;
-	if (enc_utf8 && comp)
-	    t += utf_ptr2len(t);
-	else
-	    t += (*mb_ptr2len)(t);
-    }
-    rettv->vval.v_number = (varnumber_T)(t - str);
-}
-
-/*
- * "byteidx()" function
- */
-    static void
-f_byteidx(typval_T *argvars, typval_T *rettv)
-{
-    byteidx(argvars, rettv, FALSE);
-}
-
-/*
- * "byteidxcomp()" function
- */
-    static void
-f_byteidxcomp(typval_T *argvars, typval_T *rettv)
-{
-    byteidx(argvars, rettv, TRUE);
-}
-
 /*
  * "call(func, arglist [, dict])" function
  */
@@ -2552,58 +2486,6 @@ f_charcol(typval_T *argvars, typval_T *r
     get_col(argvars, rettv, TRUE);
 }
 
-/*
- * "charidx()" function
- */
-    static void
-f_charidx(typval_T *argvars, typval_T *rettv)
-{
-    char_u	*str;
-    varnumber_T	idx;
-    varnumber_T	countcc = FALSE;
-    char_u	*p;
-    int		len;
-    int		(*ptr2len)(char_u *);
-
-    rettv->vval.v_number = -1;
-
-    if (argvars[0].v_type != VAR_STRING || argvars[1].v_type != VAR_NUMBER
-	    || (argvars[2].v_type != VAR_UNKNOWN
-					   && argvars[2].v_type != VAR_NUMBER
-					   && argvars[2].v_type != VAR_BOOL))
-    {
-	emsg(_(e_invarg));
-	return;
-    }
-
-    str = tv_get_string_chk(&argvars[0]);
-    idx = tv_get_number_chk(&argvars[1], NULL);
-    if (str == NULL || idx < 0)
-	return;
-
-    if (argvars[2].v_type != VAR_UNKNOWN)
-	countcc = tv_get_bool(&argvars[2]);
-    if (countcc < 0 || countcc > 1)
-    {
-	semsg(_(e_using_number_as_bool_nr), countcc);
-	return;
-    }
-
-    if (enc_utf8 && countcc)
-	ptr2len = utf_ptr2len;
-    else
-	ptr2len = mb_ptr2len;
-
-    for (p = str, len = 0; p <= str + idx; len++)
-    {
-	if (*p == NUL)
-	    return;
-	p += ptr2len(p);
-    }
-
-    rettv->vval.v_number = len > 0 ? len - 1 : 0;
-}
-
     win_T *
 get_optional_window(typval_T *argvars, int idx)
 {
@@ -5781,37 +5663,6 @@ f_hostname(typval_T *argvars UNUSED, typ
 }
 
 /*
- * iconv() function
- */
-    static void
-f_iconv(typval_T *argvars UNUSED, typval_T *rettv)
-{
-    char_u	buf1[NUMBUFLEN];
-    char_u	buf2[NUMBUFLEN];
-    char_u	*from, *to, *str;
-    vimconv_T	vimconv;
-
-    rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = NULL;
-
-    str = tv_get_string(&argvars[0]);
-    from = enc_canonize(enc_skip(tv_get_string_buf(&argvars[1], buf1)));
-    to = enc_canonize(enc_skip(tv_get_string_buf(&argvars[2], buf2)));
-    vimconv.vc_type = CONV_NONE;
-    convert_setup(&vimconv, from, to);
-
-    // If the encodings are equal, no conversion needed.
-    if (vimconv.vc_type == CONV_NONE)
-	rettv->vval.v_string = vim_strsave(str);
-    else
-	rettv->vval.v_string = string_convert(&vimconv, str, NULL);
-
-    convert_setup(&vimconv, NULL, NULL);
-    vim_free(from);
-    vim_free(to);
-}
-
-/*
  * "index()" function
  */
     static void
@@ -8787,452 +8638,6 @@ theend:
 }
 
 /*
- * "str2list()" function
- */
-    static void
-f_str2list(typval_T *argvars, typval_T *rettv)
-{
-    char_u	*p;
-    int		utf8 = FALSE;
-
-    if (rettv_list_alloc(rettv) == FAIL)
-	return;
-
-    if (argvars[1].v_type != VAR_UNKNOWN)
-	utf8 = (int)tv_get_bool_chk(&argvars[1], NULL);
-
-    p = tv_get_string(&argvars[0]);
-
-    if (has_mbyte || utf8)
-    {
-	int (*ptr2len)(char_u *);
-	int (*ptr2char)(char_u *);
-
-	if (utf8 || enc_utf8)
-	{
-	    ptr2len = utf_ptr2len;
-	    ptr2char = utf_ptr2char;
-	}
-	else
-	{
-	    ptr2len = mb_ptr2len;
-	    ptr2char = mb_ptr2char;
-	}
-
-	for ( ; *p != NUL; p += (*ptr2len)(p))
-	    list_append_number(rettv->vval.v_list, (*ptr2char)(p));
-    }
-    else
-	for ( ; *p != NUL; ++p)
-	    list_append_number(rettv->vval.v_list, *p);
-}
-
-/*
- * "str2nr()" function
- */
-    static void
-f_str2nr(typval_T *argvars, typval_T *rettv)
-{
-    int		base = 10;
-    char_u	*p;
-    varnumber_T	n;
-    int		what = 0;
-    int		isneg;
-
-    if (argvars[1].v_type != VAR_UNKNOWN)
-    {
-	base = (int)tv_get_number(&argvars[1]);
-	if (base != 2 && base != 8 && base != 10 && base != 16)
-	{
-	    emsg(_(e_invarg));
-	    return;
-	}
-	if (argvars[2].v_type != VAR_UNKNOWN && tv_get_bool(&argvars[2]))
-	    what |= STR2NR_QUOTE;
-    }
-
-    p = skipwhite(tv_get_string_strict(&argvars[0]));
-    isneg = (*p == '-');
-    if (*p == '+' || *p == '-')
-	p = skipwhite(p + 1);
-    switch (base)
-    {
-	case 2: what |= STR2NR_BIN + STR2NR_FORCE; break;
-	case 8: what |= STR2NR_OCT + STR2NR_OOCT + STR2NR_FORCE; break;
-	case 16: what |= STR2NR_HEX + STR2NR_FORCE; break;
-    }
-    vim_str2nr(p, NULL, NULL, what, &n, NULL, 0, FALSE);
-    // Text after the number is silently ignored.
-    if (isneg)
-	rettv->vval.v_number = -n;
-    else
-	rettv->vval.v_number = n;
-
-}
-
-/*
- * "strgetchar()" function
- */
-    static void
-f_strgetchar(typval_T *argvars, typval_T *rettv)
-{
-    char_u	*str;
-    int		len;
-    int		error = FALSE;
-    int		charidx;
-    int		byteidx = 0;
-
-    rettv->vval.v_number = -1;
-    str = tv_get_string_chk(&argvars[0]);
-    if (str == NULL)
-	return;
-    len = (int)STRLEN(str);
-    charidx = (int)tv_get_number_chk(&argvars[1], &error);
-    if (error)
-	return;
-
-    while (charidx >= 0 && byteidx < len)
-    {
-	if (charidx == 0)
-	{
-	    rettv->vval.v_number = mb_ptr2char(str + byteidx);
-	    break;
-	}
-	--charidx;
-	byteidx += MB_CPTR2LEN(str + byteidx);
-    }
-}
-
-/*
- * "stridx()" function
- */
-    static void
-f_stridx(typval_T *argvars, typval_T *rettv)
-{
-    char_u	buf[NUMBUFLEN];
-    char_u	*needle;
-    char_u	*haystack;
-    char_u	*save_haystack;
-    char_u	*pos;
-    int		start_idx;
-
-    needle = tv_get_string_chk(&argvars[1]);
-    save_haystack = haystack = tv_get_string_buf_chk(&argvars[0], buf);
-    rettv->vval.v_number = -1;
-    if (needle == NULL || haystack == NULL)
-	return;		// type error; errmsg already given
-
-    if (argvars[2].v_type != VAR_UNKNOWN)
-    {
-	int	    error = FALSE;
-
-	start_idx = (int)tv_get_number_chk(&argvars[2], &error);
-	if (error || start_idx >= (int)STRLEN(haystack))
-	    return;
-	if (start_idx >= 0)
-	    haystack += start_idx;
-    }
-
-    pos	= (char_u *)strstr((char *)haystack, (char *)needle);
-    if (pos != NULL)
-	rettv->vval.v_number = (varnumber_T)(pos - save_haystack);
-}
-
-/*
- * "string()" function
- */
-    void
-f_string(typval_T *argvars, typval_T *rettv)
-{
-    char_u	*tofree;
-    char_u	numbuf[NUMBUFLEN];
-
-    rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = tv2string(&argvars[0], &tofree, numbuf,
-								get_copyID());
-    // Make a copy if we have a value but it's not in allocated memory.
-    if (rettv->vval.v_string != NULL && tofree == NULL)
-	rettv->vval.v_string = vim_strsave(rettv->vval.v_string);
-}
-
-/*
- * "strlen()" function
- */
-    static void
-f_strlen(typval_T *argvars, typval_T *rettv)
-{
-    rettv->vval.v_number = (varnumber_T)(STRLEN(
-					      tv_get_string(&argvars[0])));
-}
-
-    static void
-strchar_common(typval_T *argvars, typval_T *rettv, int skipcc)
-{
-    char_u		*s = tv_get_string(&argvars[0]);
-    varnumber_T		len = 0;
-    int			(*func_mb_ptr2char_adv)(char_u **pp);
-
-    func_mb_ptr2char_adv = skipcc ? mb_ptr2char_adv : mb_cptr2char_adv;
-    while (*s != NUL)
-    {
-	func_mb_ptr2char_adv(&s);
-	++len;
-    }
-    rettv->vval.v_number = len;
-}
-
-/*
- * "strcharlen()" function
- */
-    static void
-f_strcharlen(typval_T *argvars, typval_T *rettv)
-{
-    strchar_common(argvars, rettv, TRUE);
-}
-
-/*
- * "strchars()" function
- */
-    static void
-f_strchars(typval_T *argvars, typval_T *rettv)
-{
-    varnumber_T		skipcc = FALSE;
-
-    if (argvars[1].v_type != VAR_UNKNOWN)
-	skipcc = tv_get_bool(&argvars[1]);
-    if (skipcc < 0 || skipcc > 1)
-	semsg(_(e_using_number_as_bool_nr), skipcc);
-    else
-	strchar_common(argvars, rettv, skipcc);
-}
-
-/*
- * "strdisplaywidth()" function
- */
-    static void
-f_strdisplaywidth(typval_T *argvars, typval_T *rettv)
-{
-    char_u	*s = tv_get_string(&argvars[0]);
-    int		col = 0;
-
-    if (argvars[1].v_type != VAR_UNKNOWN)
-	col = (int)tv_get_number(&argvars[1]);
-
-    rettv->vval.v_number = (varnumber_T)(linetabsize_col(col, s) - col);
-}
-
-/*
- * "strwidth()" function
- */
-    static void
-f_strwidth(typval_T *argvars, typval_T *rettv)
-{
-    char_u	*s = tv_get_string_strict(&argvars[0]);
-
-    rettv->vval.v_number = (varnumber_T)(mb_string2cells(s, -1));
-}
-
-/*
- * "strcharpart()" function
- */
-    static void
-f_strcharpart(typval_T *argvars, typval_T *rettv)
-{
-    char_u	*p;
-    int		nchar;
-    int		nbyte = 0;
-    int		charlen;
-    int		skipcc = FALSE;
-    int		len = 0;
-    int		slen;
-    int		error = FALSE;
-
-    p = tv_get_string(&argvars[0]);
-    slen = (int)STRLEN(p);
-
-    nchar = (int)tv_get_number_chk(&argvars[1], &error);
-    if (!error)
-    {
-	if (argvars[2].v_type != VAR_UNKNOWN
-					   && argvars[3].v_type != VAR_UNKNOWN)
-	{
-	    skipcc = tv_get_bool(&argvars[3]);
-	    if (skipcc < 0 || skipcc > 1)
-	    {
-		semsg(_(e_using_number_as_bool_nr), skipcc);
-		return;
-	    }
-	}
-
-	if (nchar > 0)
-	    while (nchar > 0 && nbyte < slen)
-	    {
-		if (skipcc)
-		    nbyte += mb_ptr2len(p + nbyte);
-		else
-		    nbyte += MB_CPTR2LEN(p + nbyte);
-		--nchar;
-	    }
-	else
-	    nbyte = nchar;
-	if (argvars[2].v_type != VAR_UNKNOWN)
-	{
-	    charlen = (int)tv_get_number(&argvars[2]);
-	    while (charlen > 0 && nbyte + len < slen)
-	    {
-		int off = nbyte + len;
-
-		if (off < 0)
-		    len += 1;
-		else
-		{
-		    if (skipcc)
-			len += mb_ptr2len(p + off);
-		    else
-			len += MB_CPTR2LEN(p + off);
-		}
-		--charlen;
-	    }
-	}
-	else
-	    len = slen - nbyte;    // default: all bytes that are available.
-    }
-
-    /*
-     * Only return the overlap between the specified part and the actual
-     * string.
-     */
-    if (nbyte < 0)
-    {
-	len += nbyte;
-	nbyte = 0;
-    }
-    else if (nbyte > slen)
-	nbyte = slen;
-    if (len < 0)
-	len = 0;
-    else if (nbyte + len > slen)
-	len = slen - nbyte;
-
-    rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = vim_strnsave(p + nbyte, len);
-}
-
-/*
- * "strpart()" function
- */
-    static void
-f_strpart(typval_T *argvars, typval_T *rettv)
-{
-    char_u	*p;
-    int		n;
-    int		len;
-    int		slen;
-    int		error = FALSE;
-
-    p = tv_get_string(&argvars[0]);
-    slen = (int)STRLEN(p);
-
-    n = (int)tv_get_number_chk(&argvars[1], &error);
-    if (error)
-	len = 0;
-    else if (argvars[2].v_type != VAR_UNKNOWN)
-	len = (int)tv_get_number(&argvars[2]);
-    else
-	len = slen - n;	    // default len: all bytes that are available.
-
-    // Only return the overlap between the specified part and the actual
-    // string.
-    if (n < 0)
-    {
-	len += n;
-	n = 0;
-    }
-    else if (n > slen)
-	n = slen;
-    if (len < 0)
-	len = 0;
-    else if (n + len > slen)
-	len = slen - n;
-
-    if (argvars[2].v_type != VAR_UNKNOWN && argvars[3].v_type != VAR_UNKNOWN)
-    {
-	int off;
-
-	// length in characters
-	for (off = n; off < slen && len > 0; --len)
-	    off += mb_ptr2len(p + off);
-	len = off - n;
-    }
-
-    rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = vim_strnsave(p + n, len);
-}
-
-/*
- * "strridx()" function
- */
-    static void
-f_strridx(typval_T *argvars, typval_T *rettv)
-{
-    char_u	buf[NUMBUFLEN];
-    char_u	*needle;
-    char_u	*haystack;
-    char_u	*rest;
-    char_u	*lastmatch = NULL;
-    int		haystack_len, end_idx;
-
-    needle = tv_get_string_chk(&argvars[1]);
-    haystack = tv_get_string_buf_chk(&argvars[0], buf);
-
-    rettv->vval.v_number = -1;
-    if (needle == NULL || haystack == NULL)
-	return;		// type error; errmsg already given
-
-    haystack_len = (int)STRLEN(haystack);
-    if (argvars[2].v_type != VAR_UNKNOWN)
-    {
-	// Third argument: upper limit for index
-	end_idx = (int)tv_get_number_chk(&argvars[2], NULL);
-	if (end_idx < 0)
-	    return;	// can never find a match
-    }
-    else
-	end_idx = haystack_len;
-
-    if (*needle == NUL)
-    {
-	// Empty string matches past the end.
-	lastmatch = haystack + end_idx;
-    }
-    else
-    {
-	for (rest = haystack; *rest != '\0'; ++rest)
-	{
-	    rest = (char_u *)strstr((char *)rest, (char *)needle);
-	    if (rest == NULL || rest > haystack + end_idx)
-		break;
-	    lastmatch = rest;
-	}
-    }
-
-    if (lastmatch == NULL)
-	rettv->vval.v_number = -1;
-    else
-	rettv->vval.v_number = (varnumber_T)(lastmatch - haystack);
-}
-
-/*
- * "strtrans()" function
- */
-    static void
-f_strtrans(typval_T *argvars, typval_T *rettv)
-{
-    rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = transstr(tv_get_string(&argvars[0]));
-}
-
-/*
  * "submatch()" function
  */
     static void
@@ -9628,236 +9033,6 @@ f_taglist(typval_T *argvars, typval_T *r
 }
 
 /*
- * "tolower(string)" function
- */
-    static void
-f_tolower(typval_T *argvars, typval_T *rettv)
-{
-    rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = strlow_save(tv_get_string(&argvars[0]));
-}
-
-/*
- * "toupper(string)" function
- */
-    static void
-f_toupper(typval_T *argvars, typval_T *rettv)
-{
-    rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = strup_save(tv_get_string(&argvars[0]));
-}
-
-/*
- * "tr(string, fromstr, tostr)" function
- */
-    static void
-f_tr(typval_T *argvars, typval_T *rettv)
-{
-    char_u	*in_str;
-    char_u	*fromstr;
-    char_u	*tostr;
-    char_u	*p;
-    int		inlen;
-    int		fromlen;
-    int		tolen;
-    int		idx;
-    char_u	*cpstr;
-    int		cplen;
-    int		first = TRUE;
-    char_u	buf[NUMBUFLEN];
-    char_u	buf2[NUMBUFLEN];
-    garray_T	ga;
-
-    in_str = tv_get_string(&argvars[0]);
-    fromstr = tv_get_string_buf_chk(&argvars[1], buf);
-    tostr = tv_get_string_buf_chk(&argvars[2], buf2);
-
-    // Default return value: empty string.
-    rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = NULL;
-    if (fromstr == NULL || tostr == NULL)
-	    return;		// type error; errmsg already given
-    ga_init2(&ga, (int)sizeof(char), 80);
-
-    if (!has_mbyte)
-	// not multi-byte: fromstr and tostr must be the same length
-	if (STRLEN(fromstr) != STRLEN(tostr))
-	{
-error:
-	    semsg(_(e_invarg2), fromstr);
-	    ga_clear(&ga);
-	    return;
-	}
-
-    // fromstr and tostr have to contain the same number of chars
-    while (*in_str != NUL)
-    {
-	if (has_mbyte)
-	{
-	    inlen = (*mb_ptr2len)(in_str);
-	    cpstr = in_str;
-	    cplen = inlen;
-	    idx = 0;
-	    for (p = fromstr; *p != NUL; p += fromlen)
-	    {
-		fromlen = (*mb_ptr2len)(p);
-		if (fromlen == inlen && STRNCMP(in_str, p, inlen) == 0)
-		{
-		    for (p = tostr; *p != NUL; p += tolen)
-		    {
-			tolen = (*mb_ptr2len)(p);
-			if (idx-- == 0)
-			{
-			    cplen = tolen;
-			    cpstr = p;
-			    break;
-			}
-		    }
-		    if (*p == NUL)	// tostr is shorter than fromstr
-			goto error;
-		    break;
-		}
-		++idx;
-	    }
-
-	    if (first && cpstr == in_str)
-	    {
-		// Check that fromstr and tostr have the same number of
-		// (multi-byte) characters.  Done only once when a character
-		// of in_str doesn't appear in fromstr.
-		first = FALSE;
-		for (p = tostr; *p != NUL; p += tolen)
-		{
-		    tolen = (*mb_ptr2len)(p);
-		    --idx;
-		}
-		if (idx != 0)
-		    goto error;
-	    }
-
-	    (void)ga_grow(&ga, cplen);
-	    mch_memmove((char *)ga.ga_data + ga.ga_len, cpstr, (size_t)cplen);
-	    ga.ga_len += cplen;
-
-	    in_str += inlen;
-	}
-	else
-	{
-	    // When not using multi-byte chars we can do it faster.
-	    p = vim_strchr(fromstr, *in_str);
-	    if (p != NULL)
-		ga_append(&ga, tostr[p - fromstr]);
-	    else
-		ga_append(&ga, *in_str);
-	    ++in_str;
-	}
-    }
-
-    // add a terminating NUL
-    (void)ga_grow(&ga, 1);
-    ga_append(&ga, NUL);
-
-    rettv->vval.v_string = ga.ga_data;
-}
-
-/*
- * "trim({expr})" function
- */
-    static void
-f_trim(typval_T *argvars, typval_T *rettv)
-{
-    char_u	buf1[NUMBUFLEN];
-    char_u	buf2[NUMBUFLEN];
-    char_u	*head = tv_get_string_buf_chk(&argvars[0], buf1);
-    char_u	*mask = NULL;
-    char_u	*tail;
-    char_u	*prev;
-    char_u	*p;
-    int		c1;
-    int		dir = 0;
-
-    rettv->v_type = VAR_STRING;
-    rettv->vval.v_string = NULL;
-    if (head == NULL)
-	return;
-
-    if (argvars[1].v_type != VAR_UNKNOWN && argvars[1].v_type != VAR_STRING)
-    {
-	semsg(_(e_invarg2), tv_get_string(&argvars[1]));
-	return;
-    }
-
-    if (argvars[1].v_type == VAR_STRING)
-    {
-	mask = tv_get_string_buf_chk(&argvars[1], buf2);
-
-	if (argvars[2].v_type != VAR_UNKNOWN)
-	{
-	    int	error = 0;
-
-	    // leading or trailing characters to trim
-	    dir = (int)tv_get_number_chk(&argvars[2], &error);
-	    if (error)
-		return;
-	    if (dir < 0 || dir > 2)
-	    {
-		semsg(_(e_invarg2), tv_get_string(&argvars[2]));
-		return;
-	    }
-	}
-    }
-
-    if (dir == 0 || dir == 1)
-    {
-	// Trim leading characters
-	while (*head != NUL)
-	{
-	    c1 = PTR2CHAR(head);
-	    if (mask == NULL)
-	    {
-		if (c1 > ' ' && c1 != 0xa0)
-		    break;
-	    }
-	    else
-	    {
-		for (p = mask; *p != NUL; MB_PTR_ADV(p))
-		    if (c1 == PTR2CHAR(p))
-			break;
-		if (*p == NUL)
-		    break;
-	    }
-	    MB_PTR_ADV(head);
-	}
-    }
-
-    tail = head + STRLEN(head);
-    if (dir == 0 || dir == 2)
-    {
-	// Trim trailing characters
-	for (; tail > head; tail = prev)
-	{
-	    prev = tail;
-	    MB_PTR_BACK(head, prev);
-	    c1 = PTR2CHAR(prev);
-	    if (mask == NULL)
-	    {
-		if (c1 > ' ' && c1 != 0xa0)
-		    break;
-	    }
-	    else
-	    {
-		for (p = mask; *p != NUL; MB_PTR_ADV(p))
-		    if (c1 == PTR2CHAR(p))
-			break;
-		if (*p == NUL)
-		    break;
-	    }
-	}
-    }
-    rettv->vval.v_string = vim_strnsave(head, tail - head);
-}
-
-/*
  * "type(expr)" function
  */
     static void
diff --git a/src/mbyte.c b/src/mbyte.c
--- a/src/mbyte.c
+++ b/src/mbyte.c
@@ -4961,6 +4961,37 @@ f_getimstatus(typval_T *argvars UNUSED, 
     rettv->vval.v_number = im_get_status();
 # endif
 }
+
+/*
+ * iconv() function
+ */
+    void
+f_iconv(typval_T *argvars UNUSED, typval_T *rettv)
+{
+    char_u	buf1[NUMBUFLEN];
+    char_u	buf2[NUMBUFLEN];
+    char_u	*from, *to, *str;
+    vimconv_T	vimconv;
+
+    rettv->v_type = VAR_STRING;
+    rettv->vval.v_string = NULL;
+
+    str = tv_get_string(&argvars[0]);
+    from = enc_canonize(enc_skip(tv_get_string_buf(&argvars[1], buf1)));
+    to = enc_canonize(enc_skip(tv_get_string_buf(&argvars[2], buf2)));
+    vimconv.vc_type = CONV_NONE;
+    convert_setup(&vimconv, from, to);
+
+    // If the encodings are equal, no conversion needed.
+    if (vimconv.vc_type == CONV_NONE)
+	rettv->vval.v_string = vim_strsave(str);
+    else
+	rettv->vval.v_string = string_convert(&vimconv, str, NULL);
+
+    convert_setup(&vimconv, NULL, NULL);
+    vim_free(from);
+    vim_free(to);
+}
 #endif
 
 /*
diff --git a/src/misc1.c b/src/misc1.c
--- a/src/misc1.c
+++ b/src/misc1.c
@@ -695,7 +695,8 @@ f_mode(typval_T *argvars, typval_T *rett
 	if (finish_op)
 	{
 	    buf[1] = 'o';
-	    // to be able to detect force-linewise/blockwise/characterwise operations
+	    // to be able to detect force-linewise/blockwise/characterwise
+	    // operations
 	    buf[2] = motion_force;
 	}
 	else if (restart_edit == 'I' || restart_edit == 'R'
@@ -2099,29 +2100,6 @@ match_user(char_u *name)
     return result;
 }
 
-/*
- * Concatenate two strings and return the result in allocated memory.
- * Returns NULL when out of memory.
- */
-    char_u  *
-concat_str(char_u *str1, char_u *str2)
-{
-    char_u  *dest;
-    size_t  l = str1 == NULL ? 0 : STRLEN(str1);
-
-    dest = alloc(l + (str2 == NULL ? 0 : STRLEN(str2)) + 1L);
-    if (dest != NULL)
-    {
-	if (str1 == NULL)
-	    *dest = NUL;
-	else
-	    STRCPY(dest, str1);
-	if (str2 != NULL)
-	    STRCPY(dest + l, str2);
-    }
-    return dest;
-}
-
     static void
 prepare_to_exit(void)
 {
diff --git a/src/misc2.c b/src/misc2.c
--- a/src/misc2.c
+++ b/src/misc2.c
@@ -1268,42 +1268,6 @@ free_all_mem(void)
 #endif
 
 /*
- * Copy "string" into newly allocated memory.
- */
-    char_u *
-vim_strsave(char_u *string)
-{
-    char_u	*p;
-    size_t	len;
-
-    len = STRLEN(string) + 1;
-    p = alloc(len);
-    if (p != NULL)
-	mch_memmove(p, string, len);
-    return p;
-}
-
-/*
- * Copy up to "len" bytes of "string" into newly allocated memory and
- * terminate with a NUL.
- * The allocated memory always has size "len + 1", also when "string" is
- * shorter.
- */
-    char_u *
-vim_strnsave(char_u *string, size_t len)
-{
-    char_u	*p;
-
-    p = alloc(len + 1);
-    if (p != NULL)
-    {
-	STRNCPY(p, string, len);
-	p[len] = NUL;
-    }
-    return p;
-}
-
-/*
  * Copy "p[len]" into allocated memory, ignoring NUL characters.
  * Returns NULL when out of memory.
  */
@@ -1318,465 +1282,6 @@ vim_memsave(char_u *p, size_t len)
 }
 
 /*
- * Same as vim_strsave(), but any characters found in esc_chars are preceded
- * by a backslash.
- */
-    char_u *
-vim_strsave_escaped(char_u *string, char_u *esc_chars)
-{
-    return vim_strsave_escaped_ext(string, esc_chars, '\\', FALSE);
-}
-
-/*
- * Same as vim_strsave_escaped(), but when "bsl" is TRUE also escape
- * characters where rem_backslash() would remove the backslash.
- * Escape the characters with "cc".
- */
-    char_u *
-vim_strsave_escaped_ext(
-    char_u	*string,
-    char_u	*esc_chars,
-    int		cc,
-    int		bsl)
-{
-    char_u	*p;
-    char_u	*p2;
-    char_u	*escaped_string;
-    unsigned	length;
-    int		l;
-
-    /*
-     * First count the number of backslashes required.
-     * Then allocate the memory and insert them.
-     */
-    length = 1;				// count the trailing NUL
-    for (p = string; *p; p++)
-    {
-	if (has_mbyte && (l = (*mb_ptr2len)(p)) > 1)
-	{
-	    length += l;		// count a multibyte char
-	    p += l - 1;
-	    continue;
-	}
-	if (vim_strchr(esc_chars, *p) != NULL || (bsl && rem_backslash(p)))
-	    ++length;			// count a backslash
-	++length;			// count an ordinary char
-    }
-    escaped_string = alloc(length);
-    if (escaped_string != NULL)
-    {
-	p2 = escaped_string;
-	for (p = string; *p; p++)
-	{
-	    if (has_mbyte && (l = (*mb_ptr2len)(p)) > 1)
-	    {
-		mch_memmove(p2, p, (size_t)l);
-		p2 += l;
-		p += l - 1;		// skip multibyte char
-		continue;
-	    }
-	    if (vim_strchr(esc_chars, *p) != NULL || (bsl && rem_backslash(p)))
-		*p2++ = cc;
-	    *p2++ = *p;
-	}
-	*p2 = NUL;
-    }
-    return escaped_string;
-}
-
-/*
- * Return TRUE when 'shell' has "csh" in the tail.
- */
-    int
-csh_like_shell(void)
-{
-    return (strstr((char *)gettail(p_sh), "csh") != NULL);
-}
-
-/*
- * Escape "string" for use as a shell argument with system().
- * This uses single quotes, except when we know we need to use double quotes
- * (MS-DOS and MS-Windows not using PowerShell and without 'shellslash' set).
- * PowerShell also uses a novel escaping for enclosed single quotes - double
- * them up.
- * Escape a newline, depending on the 'shell' option.
- * When "do_special" is TRUE also replace "!", "%", "#" and things starting
- * with "<" like "<cfile>".
- * When "do_newline" is FALSE do not escape newline unless it is csh shell.
- * Returns the result in allocated memory, NULL if we have run out.
- */
-    char_u *
-vim_strsave_shellescape(char_u *string, int do_special, int do_newline)
-{
-    unsigned	length;
-    char_u	*p;
-    char_u	*d;
-    char_u	*escaped_string;
-    int		l;
-    int		csh_like;
-    char_u	*shname;
-    int		powershell;
-# ifdef MSWIN
-    int		double_quotes;
-# endif
-
-    // Only csh and similar shells expand '!' within single quotes.  For sh and
-    // the like we must not put a backslash before it, it will be taken
-    // literally.  If do_special is set the '!' will be escaped twice.
-    // Csh also needs to have "\n" escaped twice when do_special is set.
-    csh_like = csh_like_shell();
-
-    // PowerShell uses it's own version for quoting single quotes
-    shname = gettail(p_sh);
-    powershell = strstr((char *)shname, "pwsh") != NULL;
-# ifdef MSWIN
-    powershell = powershell || strstr((char *)shname, "powershell") != NULL;
-    // PowerShell only accepts single quotes so override shellslash.
-    double_quotes = !powershell && !p_ssl;
-# endif
-
-    // First count the number of extra bytes required.
-    length = (unsigned)STRLEN(string) + 3;  // two quotes and a trailing NUL
-    for (p = string; *p != NUL; MB_PTR_ADV(p))
-    {
-# ifdef MSWIN
-	if (double_quotes)
-	{
-	    if (*p == '"')
-		++length;		// " -> ""
-	}
-	else
-# endif
-	if (*p == '\'')
-	{
-	    if (powershell)
-		length +=2;		// ' => ''
-	    else
-		length += 3;		// ' => '\''
-	}
-	if ((*p == '\n' && (csh_like || do_newline))
-		|| (*p == '!' && (csh_like || do_special)))
-	{
-	    ++length;			// insert backslash
-	    if (csh_like && do_special)
-		++length;		// insert backslash
-	}
-	if (do_special && find_cmdline_var(p, &l) >= 0)
-	{
-	    ++length;			// insert backslash
-	    p += l - 1;
-	}
-    }
-
-    // Allocate memory for the result and fill it.
-    escaped_string = alloc(length);
-    if (escaped_string != NULL)
-    {
-	d = escaped_string;
-
-	// add opening quote
-# ifdef MSWIN
-	if (double_quotes)
-	    *d++ = '"';
-	else
-# endif
-	    *d++ = '\'';
-
-	for (p = string; *p != NUL; )
-	{
-# ifdef MSWIN
-	    if (double_quotes)
-	    {
-		if (*p == '"')
-		{
-		    *d++ = '"';
-		    *d++ = '"';
-		    ++p;
-		    continue;
-		}
-	    }
-	    else
-# endif
-	    if (*p == '\'')
-	    {
-		if (powershell)
-		{
-		    *d++ = '\'';
-		    *d++ = '\'';
-		}
-		else
-		{
-		    *d++ = '\'';
-		    *d++ = '\\';
-		    *d++ = '\'';
-		    *d++ = '\'';
-		}
-		++p;
-		continue;
-	    }
-	    if ((*p == '\n' && (csh_like || do_newline))
-		    || (*p == '!' && (csh_like || do_special)))
-	    {
-		*d++ = '\\';
-		if (csh_like && do_special)
-		    *d++ = '\\';
-		*d++ = *p++;
-		continue;
-	    }
-	    if (do_special && find_cmdline_var(p, &l) >= 0)
-	    {
-		*d++ = '\\';		// insert backslash
-		while (--l >= 0)	// copy the var
-		    *d++ = *p++;
-		continue;
-	    }
-
-	    MB_COPY_CHAR(p, d);
-	}
-
-	// add terminating quote and finish with a NUL
-# ifdef MSWIN
-	if (double_quotes)
-	    *d++ = '"';
-	else
-# endif
-	    *d++ = '\'';
-	*d = NUL;
-    }
-
-    return escaped_string;
-}
-
-/*
- * Like vim_strsave(), but make all characters uppercase.
- * This uses ASCII lower-to-upper case translation, language independent.
- */
-    char_u *
-vim_strsave_up(char_u *string)
-{
-    char_u *p1;
-
-    p1 = vim_strsave(string);
-    vim_strup(p1);
-    return p1;
-}
-
-/*
- * Like vim_strnsave(), but make all characters uppercase.
- * This uses ASCII lower-to-upper case translation, language independent.
- */
-    char_u *
-vim_strnsave_up(char_u *string, size_t len)
-{
-    char_u *p1;
-
-    p1 = vim_strnsave(string, len);
-    vim_strup(p1);
-    return p1;
-}
-
-/*
- * ASCII lower-to-upper case translation, language independent.
- */
-    void
-vim_strup(
-    char_u	*p)
-{
-    char_u  *p2;
-    int	    c;
-
-    if (p != NULL)
-    {
-	p2 = p;
-	while ((c = *p2) != NUL)
-#ifdef EBCDIC
-	    *p2++ = isalpha(c) ? toupper(c) : c;
-#else
-	    *p2++ = (c < 'a' || c > 'z') ? c : (c - 0x20);
-#endif
-    }
-}
-
-#if defined(FEAT_EVAL) || defined(FEAT_SPELL) || defined(PROTO)
-/*
- * Make string "s" all upper-case and return it in allocated memory.
- * Handles multi-byte characters as well as possible.
- * Returns NULL when out of memory.
- */
-    char_u *
-strup_save(char_u *orig)
-{
-    char_u	*p;
-    char_u	*res;
-
-    res = p = vim_strsave(orig);
-
-    if (res != NULL)
-	while (*p != NUL)
-	{
-	    int		l;
-
-	    if (enc_utf8)
-	    {
-		int	c, uc;
-		int	newl;
-		char_u	*s;
-
-		c = utf_ptr2char(p);
-		l = utf_ptr2len(p);
-		if (c == 0)
-		{
-		    // overlong sequence, use only the first byte
-		    c = *p;
-		    l = 1;
-		}
-		uc = utf_toupper(c);
-
-		// Reallocate string when byte count changes.  This is rare,
-		// thus it's OK to do another malloc()/free().
-		newl = utf_char2len(uc);
-		if (newl != l)
-		{
-		    s = alloc(STRLEN(res) + 1 + newl - l);
-		    if (s == NULL)
-		    {
-			vim_free(res);
-			return NULL;
-		    }
-		    mch_memmove(s, res, p - res);
-		    STRCPY(s + (p - res) + newl, p + l);
-		    p = s + (p - res);
-		    vim_free(res);
-		    res = s;
-		}
-
-		utf_char2bytes(uc, p);
-		p += newl;
-	    }
-	    else if (has_mbyte && (l = (*mb_ptr2len)(p)) > 1)
-		p += l;		// skip multi-byte character
-	    else
-	    {
-		*p = TOUPPER_LOC(*p); // note that toupper() can be a macro
-		p++;
-	    }
-	}
-
-    return res;
-}
-
-/*
- * Make string "s" all lower-case and return it in allocated memory.
- * Handles multi-byte characters as well as possible.
- * Returns NULL when out of memory.
- */
-    char_u *
-strlow_save(char_u *orig)
-{
-    char_u	*p;
-    char_u	*res;
-
-    res = p = vim_strsave(orig);
-
-    if (res != NULL)
-	while (*p != NUL)
-	{
-	    int		l;
-
-	    if (enc_utf8)
-	    {
-		int	c, lc;
-		int	newl;
-		char_u	*s;
-
-		c = utf_ptr2char(p);
-		l = utf_ptr2len(p);
-		if (c == 0)
-		{
-		    // overlong sequence, use only the first byte
-		    c = *p;
-		    l = 1;
-		}
-		lc = utf_tolower(c);
-
-		// Reallocate string when byte count changes.  This is rare,
-		// thus it's OK to do another malloc()/free().
-		newl = utf_char2len(lc);
-		if (newl != l)
-		{
-		    s = alloc(STRLEN(res) + 1 + newl - l);
-		    if (s == NULL)
-		    {
-			vim_free(res);
-			return NULL;
-		    }
-		    mch_memmove(s, res, p - res);
-		    STRCPY(s + (p - res) + newl, p + l);
-		    p = s + (p - res);
-		    vim_free(res);
-		    res = s;
-		}
-
-		utf_char2bytes(lc, p);
-		p += newl;
-	    }
-	    else if (has_mbyte && (l = (*mb_ptr2len)(p)) > 1)
-		p += l;		// skip multi-byte character
-	    else
-	    {
-		*p = TOLOWER_LOC(*p); // note that tolower() can be a macro
-		p++;
-	    }
-	}
-
-    return res;
-}
-#endif
-
-/*
- * delete spaces at the end of a string
- */
-    void
-del_trailing_spaces(char_u *ptr)
-{
-    char_u	*q;
-
-    q = ptr + STRLEN(ptr);
-    while (--q > ptr && VIM_ISWHITE(q[0]) && q[-1] != '\\' && q[-1] != Ctrl_V)
-	*q = NUL;
-}
-
-/*
- * Like strncpy(), but always terminate the result with one NUL.
- * "to" must be "len + 1" long!
- */
-    void
-vim_strncpy(char_u *to, char_u *from, size_t len)
-{
-    STRNCPY(to, from, len);
-    to[len] = NUL;
-}
-
-/*
- * Like strcat(), but make sure the result fits in "tosize" bytes and is
- * always NUL terminated. "from" and "to" may overlap.
- */
-    void
-vim_strcat(char_u *to, char_u *from, size_t tosize)
-{
-    size_t tolen = STRLEN(to);
-    size_t fromlen = STRLEN(from);
-
-    if (tolen + fromlen + 1 > tosize)
-    {
-	mch_memmove(to + tolen, from, tosize - tolen - 1);
-	to[tosize - 1] = NUL;
-    }
-    else
-	mch_memmove(to + tolen, from, fromlen + 1);
-}
-
-/*
  * Isolate one part of a string option where parts are separated with
  * "sep_chars".
  * The part is copied into "buf[maxlen]".
@@ -1848,180 +1353,6 @@ vim_memset(void *ptr, int c, size_t size
 }
 #endif
 
-#if (!defined(HAVE_STRCASECMP) && !defined(HAVE_STRICMP)) || defined(PROTO)
-/*
- * Compare two strings, ignoring case, using current locale.
- * Doesn't work for multi-byte characters.
- * return 0 for match, < 0 for smaller, > 0 for bigger
- */
-    int
-vim_stricmp(char *s1, char *s2)
-{
-    int		i;
-
-    for (;;)
-    {
-	i = (int)TOLOWER_LOC(*s1) - (int)TOLOWER_LOC(*s2);
-	if (i != 0)
-	    return i;			    // this character different
-	if (*s1 == NUL)
-	    break;			    // strings match until NUL
-	++s1;
-	++s2;
-    }
-    return 0;				    // strings match
-}
-#endif
-
-#if (!defined(HAVE_STRNCASECMP) && !defined(HAVE_STRNICMP)) || defined(PROTO)
-/*
- * Compare two strings, for length "len", ignoring case, using current locale.
- * Doesn't work for multi-byte characters.
- * return 0 for match, < 0 for smaller, > 0 for bigger
- */
-    int
-vim_strnicmp(char *s1, char *s2, size_t len)
-{
-    int		i;
-
-    while (len > 0)
-    {
-	i = (int)TOLOWER_LOC(*s1) - (int)TOLOWER_LOC(*s2);
-	if (i != 0)
-	    return i;			    // this character different
-	if (*s1 == NUL)
-	    break;			    // strings match until NUL
-	++s1;
-	++s2;
-	--len;
-    }
-    return 0;				    // strings match
-}
-#endif
-
-/*
- * Search for first occurrence of "c" in "string".
- * Version of strchr() that handles unsigned char strings with characters from
- * 128 to 255 correctly.  It also doesn't return a pointer to the NUL at the
- * end of the string.
- */
-    char_u  *
-vim_strchr(char_u *string, int c)
-{
-    char_u	*p;
-    int		b;
-
-    p = string;
-    if (enc_utf8 && c >= 0x80)
-    {
-	while (*p != NUL)
-	{
-	    int l = utfc_ptr2len(p);
-
-	    // Avoid matching an illegal byte here.
-	    if (utf_ptr2char(p) == c && l > 1)
-		return p;
-	    p += l;
-	}
-	return NULL;
-    }
-    if (enc_dbcs != 0 && c > 255)
-    {
-	int	n2 = c & 0xff;
-
-	c = ((unsigned)c >> 8) & 0xff;
-	while ((b = *p) != NUL)
-	{
-	    if (b == c && p[1] == n2)
-		return p;
-	    p += (*mb_ptr2len)(p);
-	}
-	return NULL;
-    }
-    if (has_mbyte)
-    {
-	while ((b = *p) != NUL)
-	{
-	    if (b == c)
-		return p;
-	    p += (*mb_ptr2len)(p);
-	}
-	return NULL;
-    }
-    while ((b = *p) != NUL)
-    {
-	if (b == c)
-	    return p;
-	++p;
-    }
-    return NULL;
-}
-
-/*
- * Version of strchr() that only works for bytes and handles unsigned char
- * strings with characters above 128 correctly. It also doesn't return a
- * pointer to the NUL at the end of the string.
- */
-    char_u  *
-vim_strbyte(char_u *string, int c)
-{
-    char_u	*p = string;
-
-    while (*p != NUL)
-    {
-	if (*p == c)
-	    return p;
-	++p;
-    }
-    return NULL;
-}
-
-/*
- * Search for last occurrence of "c" in "string".
- * Version of strrchr() that handles unsigned char strings with characters from
- * 128 to 255 correctly.  It also doesn't return a pointer to the NUL at the
- * end of the string.
- * Return NULL if not found.
- * Does not handle multi-byte char for "c"!
- */
-    char_u  *
-vim_strrchr(char_u *string, int c)
-{
-    char_u	*retval = NULL;
-    char_u	*p = string;
-
-    while (*p)
-    {
-	if (*p == c)
-	    retval = p;
-	MB_PTR_ADV(p);
-    }
-    return retval;
-}
-
-/*
- * Vim's version of strpbrk(), in case it's missing.
- * Don't generate a prototype for this, causes problems when it's not used.
- */
-#ifndef PROTO
-# ifndef HAVE_STRPBRK
-#  ifdef vim_strpbrk
-#   undef vim_strpbrk
-#  endif
-    char_u *
-vim_strpbrk(char_u *s, char_u *charset)
-{
-    while (*s)
-    {
-	if (vim_strchr(charset, *s) != NULL)
-	    return s;
-	MB_PTR_ADV(s);
-    }
-    return NULL;
-}
-# endif
-#endif
-
 /*
  * Vim has its own isspace() function, because on some machines isspace()
  * can't handle characters above 128.
@@ -3975,25 +3306,6 @@ qsort(
 #endif
 
 /*
- * Sort an array of strings.
- */
-static int sort_compare(const void *s1, const void *s2);
-
-    static int
-sort_compare(const void *s1, const void *s2)
-{
-    return STRCMP(*(char **)s1, *(char **)s2);
-}
-
-    void
-sort_strings(
-    char_u	**files,
-    int		count)
-{
-    qsort((void *)files, (size_t)count, sizeof(char_u *), sort_compare);
-}
-
-/*
  * The putenv() implementation below comes from the "screen" program.
  * Included with permission from Juergen Weigert.
  * See pty.c for the copyright notice.
@@ -4304,24 +3616,6 @@ put_bytes(FILE *fd, long_u nr, int len)
 
 #endif
 
-#if defined(FEAT_QUICKFIX) || defined(FEAT_SPELL) || defined(PROTO)
-/*
- * Return TRUE if string "s" contains a non-ASCII character (128 or higher).
- * When "s" is NULL FALSE is returned.
- */
-    int
-has_non_ascii(char_u *s)
-{
-    char_u	*p;
-
-    if (s != NULL)
-	for (p = s; *p != NUL; ++p)
-	    if (*p >= 128)
-		return TRUE;
-    return FALSE;
-}
-#endif
-
 #ifndef PROTO  // proto is defined in vim.h
 # ifdef ELAPSED_TIMEVAL
 /*
diff --git a/src/proto.h b/src/proto.h
--- a/src/proto.h
+++ b/src/proto.h
@@ -211,6 +211,7 @@ void mbyte_im_set_active(int active_arg)
 # include "spell.pro"
 # include "spellfile.pro"
 # include "spellsuggest.pro"
+# include "strings.pro"
 # include "syntax.pro"
 # include "tag.pro"
 # include "term.pro"
diff --git a/src/proto/eval.pro b/src/proto/eval.pro
--- a/src/proto/eval.pro
+++ b/src/proto/eval.pro
@@ -32,8 +32,6 @@ int next_for_item(void *fi_void, char_u 
 void free_for_info(void *fi_void);
 void set_context_for_expression(expand_T *xp, char_u *arg, cmdidx_T cmdidx);
 int pattern_match(char_u *pat, char_u *text, int ic);
-char_u *eval_next_non_blank(char_u *arg, evalarg_T *evalarg, int *getnext);
-char_u *eval_next_line(evalarg_T *evalarg);
 char_u *skipwhite_and_linebreak(char_u *arg, evalarg_T *evalarg);
 void clear_evalarg(evalarg_T *evalarg, exarg_T *eap);
 int eval0(char_u *arg, typval_T *rettv, exarg_T *eap, evalarg_T *evalarg);
@@ -55,7 +53,6 @@ int set_ref_in_list_items(list_T *l, int
 int set_ref_in_item(typval_T *tv, int copyID, ht_stack_T **ht_stack, list_stack_T **list_stack);
 char_u *echo_string_core(typval_T *tv, char_u **tofree, char_u *numbuf, int copyID, int echo_style, int restore_copyID, int composite_val);
 char_u *echo_string(typval_T *tv, char_u **tofree, char_u *numbuf, int copyID);
-char_u *string_quote(char_u *str, int function);
 int buf_byteidx_to_charidx(buf_T *buf, int lnum, int byteidx);
 int buf_charidx_to_byteidx(buf_T *buf, int lnum, int charidx);
 pos_T *var2fpos(typval_T *varp, int dollar_lnum, int *fnum, int charcol);
diff --git a/src/proto/evalfunc.pro b/src/proto/evalfunc.pro
--- a/src/proto/evalfunc.pro
+++ b/src/proto/evalfunc.pro
@@ -23,5 +23,4 @@ int dynamic_feature(char_u *feature);
 void mzscheme_call_vim(char_u *name, typval_T *args, typval_T *rettv);
 void range_list_materialize(list_T *list);
 long do_searchpair(char_u *spat, char_u *mpat, char_u *epat, int dir, typval_T *skip, int flags, pos_T *match_pos, linenr_T lnum_stop, long time_limit);
-void f_string(typval_T *argvars, typval_T *rettv);
 /* vim: set ft=c : */
diff --git a/src/proto/mbyte.pro b/src/proto/mbyte.pro
--- a/src/proto/mbyte.pro
+++ b/src/proto/mbyte.pro
@@ -86,4 +86,5 @@ char_u *string_convert(vimconv_T *vcp, c
 char_u *string_convert_ext(vimconv_T *vcp, char_u *ptr, int *lenp, int *unconvlenp);
 void f_setcellwidths(typval_T *argvars, typval_T *rettv);
 void f_charclass(typval_T *argvars, typval_T *rettv);
+void f_iconv(typval_T *argvars UNUSED, typval_T *rettv);
 /* vim: set ft=c : */
diff --git a/src/proto/misc1.pro b/src/proto/misc1.pro
--- a/src/proto/misc1.pro
+++ b/src/proto/misc1.pro
@@ -36,7 +36,6 @@ void vim_setenv(char_u *name, char_u *va
 char_u *get_env_name(expand_T *xp, int idx);
 char_u *get_users(expand_T *xp, int idx);
 int match_user(char_u *name);
-char_u *concat_str(char_u *str1, char_u *str2);
 void preserve_exit(void);
 void line_breakcheck(void);
 void fast_breakcheck(void);
diff --git a/src/proto/misc2.pro b/src/proto/misc2.pro
--- a/src/proto/misc2.pro
+++ b/src/proto/misc2.pro
@@ -31,28 +31,9 @@ void *lalloc_id(size_t size, int message
 void *mem_realloc(void *ptr, size_t size);
 void do_outofmem_msg(size_t size);
 void free_all_mem(void);
-char_u *vim_strsave(char_u *string);
-char_u *vim_strnsave(char_u *string, size_t len);
 char_u *vim_memsave(char_u *p, size_t len);
-char_u *vim_strsave_escaped(char_u *string, char_u *esc_chars);
-char_u *vim_strsave_escaped_ext(char_u *string, char_u *esc_chars, int cc, int bsl);
-int csh_like_shell(void);
-char_u *vim_strsave_shellescape(char_u *string, int do_special, int do_newline);
-char_u *vim_strsave_up(char_u *string);
-char_u *vim_strnsave_up(char_u *string, size_t len);
-void vim_strup(char_u *p);
-char_u *strup_save(char_u *orig);
-char_u *strlow_save(char_u *orig);
-void del_trailing_spaces(char_u *ptr);
-void vim_strncpy(char_u *to, char_u *from, size_t len);
-void vim_strcat(char_u *to, char_u *from, size_t tosize);
 int copy_option_part(char_u **option, char_u *buf, int maxlen, char *sep_chars);
 void vim_free(void *x);
-int vim_stricmp(char *s1, char *s2);
-int vim_strnicmp(char *s1, char *s2, size_t len);
-char_u *vim_strchr(char_u *string, int c);
-char_u *vim_strbyte(char_u *string, int c);
-char_u *vim_strrchr(char_u *string, int c);
 int vim_isspace(int x);
 void ga_clear(garray_T *gap);
 void ga_clear_strings(garray_T *gap);
@@ -93,14 +74,12 @@ int get_shape_idx(int mouse);
 void update_mouseshape(int shape_idx);
 int vim_chdir(char_u *new_dir);
 int get_user_name(char_u *buf, int len);
-void sort_strings(char_u **files, int count);
 int filewritable(char_u *fname);
 int get2c(FILE *fd);
 int get3c(FILE *fd);
 int get4c(FILE *fd);
 char_u *read_string(FILE *fd, int cnt);
 int put_bytes(FILE *fd, long_u nr, int len);
-int has_non_ascii(char_u *s);
 int mch_parse_cmd(char_u *cmd, int use_shcf, char ***argv, int *argc);
 int build_argv_from_string(char_u *cmd, char ***argv, int *argc);
 int build_argv_from_list(list_T *l, char ***argv, int *argc);
diff --git a/src/proto/strings.pro b/src/proto/strings.pro
new file mode 100644
--- /dev/null
+++ b/src/proto/strings.pro
@@ -0,0 +1,45 @@
+/* strings.c */
+char_u *vim_strsave(char_u *string);
+char_u *vim_strnsave(char_u *string, size_t len);
+char_u *vim_strsave_escaped(char_u *string, char_u *esc_chars);
+char_u *vim_strsave_escaped_ext(char_u *string, char_u *esc_chars, int cc, int bsl);
+int csh_like_shell(void);
+char_u *vim_strsave_shellescape(char_u *string, int do_special, int do_newline);
+char_u *vim_strsave_up(char_u *string);
+char_u *vim_strnsave_up(char_u *string, size_t len);
+void vim_strup(char_u *p);
+char_u *strlow_save(char_u *orig);
+void del_trailing_spaces(char_u *ptr);
+void vim_strncpy(char_u *to, char_u *from, size_t len);
+void vim_strcat(char_u *to, char_u *from, size_t tosize);
+int vim_stricmp(char *s1, char *s2);
+int vim_strnicmp(char *s1, char *s2, size_t len);
+char_u *vim_strchr(char_u *string, int c);
+char_u *vim_strbyte(char_u *string, int c);
+char_u *vim_strrchr(char_u *string, int c);
+void sort_strings(char_u **files, int count);
+int has_non_ascii(char_u *s);
+char_u *concat_str(char_u *str1, char_u *str2);
+char_u *string_quote(char_u *str, int function);
+void f_byteidx(typval_T *argvars, typval_T *rettv);
+void f_byteidxcomp(typval_T *argvars, typval_T *rettv);
+void f_charidx(typval_T *argvars, typval_T *rettv);
+void f_str2list(typval_T *argvars, typval_T *rettv);
+void f_str2nr(typval_T *argvars, typval_T *rettv);
+void f_strgetchar(typval_T *argvars, typval_T *rettv);
+void f_stridx(typval_T *argvars, typval_T *rettv);
+void f_string(typval_T *argvars, typval_T *rettv);
+void f_strlen(typval_T *argvars, typval_T *rettv);
+void f_strcharlen(typval_T *argvars, typval_T *rettv);
+void f_strchars(typval_T *argvars, typval_T *rettv);
+void f_strdisplaywidth(typval_T *argvars, typval_T *rettv);
+void f_strwidth(typval_T *argvars, typval_T *rettv);
+void f_strcharpart(typval_T *argvars, typval_T *rettv);
+void f_strpart(typval_T *argvars, typval_T *rettv);
+void f_strridx(typval_T *argvars, typval_T *rettv);
+void f_strtrans(typval_T *argvars, typval_T *rettv);
+void f_tolower(typval_T *argvars, typval_T *rettv);
+void f_toupper(typval_T *argvars, typval_T *rettv);
+void f_tr(typval_T *argvars, typval_T *rettv);
+void f_trim(typval_T *argvars, typval_T *rettv);
+/* vim: set ft=c : */
diff --git a/src/strings.c b/src/strings.c
new file mode 100644
--- /dev/null
+++ b/src/strings.c
@@ -0,0 +1,1563 @@
+/* vi:set ts=8 sts=4 sw=4 noet:
+ *
+ * VIM - Vi IMproved	by Bram Moolenaar
+ *
+ * Do ":help uganda"  in Vim to read copying and usage conditions.
+ * Do ":help credits" in Vim to see a list of people who contributed.
+ * See README.txt for an overview of the Vim source code.
+ */
+
+/*
+ * strings.c: string manipulation functions
+ */
+
+#include "vim.h"
+
+/*
+ * Copy "string" into newly allocated memory.
+ */
+    char_u *
+vim_strsave(char_u *string)
+{
+    char_u	*p;
+    size_t	len;
+
+    len = STRLEN(string) + 1;
+    p = alloc(len);
+    if (p != NULL)
+	mch_memmove(p, string, len);
+    return p;
+}
+
+/*
+ * Copy up to "len" bytes of "string" into newly allocated memory and
+ * terminate with a NUL.
+ * The allocated memory always has size "len + 1", also when "string" is
+ * shorter.
+ */
+    char_u *
+vim_strnsave(char_u *string, size_t len)
+{
+    char_u	*p;
+
+    p = alloc(len + 1);
+    if (p != NULL)
+    {
+	STRNCPY(p, string, len);
+	p[len] = NUL;
+    }
+    return p;
+}
+
+/*
+ * Same as vim_strsave(), but any characters found in esc_chars are preceded
+ * by a backslash.
+ */
+    char_u *
+vim_strsave_escaped(char_u *string, char_u *esc_chars)
+{
+    return vim_strsave_escaped_ext(string, esc_chars, '\\', FALSE);
+}
+
+/*
+ * Same as vim_strsave_escaped(), but when "bsl" is TRUE also escape
+ * characters where rem_backslash() would remove the backslash.
+ * Escape the characters with "cc".
+ */
+    char_u *
+vim_strsave_escaped_ext(
+    char_u	*string,
+    char_u	*esc_chars,
+    int		cc,
+    int		bsl)
+{
+    char_u	*p;
+    char_u	*p2;
+    char_u	*escaped_string;
+    unsigned	length;
+    int		l;
+
+    /*
+     * First count the number of backslashes required.
+     * Then allocate the memory and insert them.
+     */
+    length = 1;				// count the trailing NUL
+    for (p = string; *p; p++)
+    {
+	if (has_mbyte && (l = (*mb_ptr2len)(p)) > 1)
+	{
+	    length += l;		// count a multibyte char
+	    p += l - 1;
+	    continue;
+	}
+	if (vim_strchr(esc_chars, *p) != NULL || (bsl && rem_backslash(p)))
+	    ++length;			// count a backslash
+	++length;			// count an ordinary char
+    }
+    escaped_string = alloc(length);
+    if (escaped_string != NULL)
+    {
+	p2 = escaped_string;
+	for (p = string; *p; p++)
+	{
+	    if (has_mbyte && (l = (*mb_ptr2len)(p)) > 1)
+	    {
+		mch_memmove(p2, p, (size_t)l);
+		p2 += l;
+		p += l - 1;		// skip multibyte char
+		continue;
+	    }
+	    if (vim_strchr(esc_chars, *p) != NULL || (bsl && rem_backslash(p)))
+		*p2++ = cc;
+	    *p2++ = *p;
+	}
+	*p2 = NUL;
+    }
+    return escaped_string;
+}
+
+/*
+ * Return TRUE when 'shell' has "csh" in the tail.
+ */
+    int
+csh_like_shell(void)
+{
+    return (strstr((char *)gettail(p_sh), "csh") != NULL);
+}
+
+/*
+ * Escape "string" for use as a shell argument with system().
+ * This uses single quotes, except when we know we need to use double quotes
+ * (MS-DOS and MS-Windows not using PowerShell and without 'shellslash' set).
+ * PowerShell also uses a novel escaping for enclosed single quotes - double
+ * them up.
+ * Escape a newline, depending on the 'shell' option.
+ * When "do_special" is TRUE also replace "!", "%", "#" and things starting
+ * with "<" like "<cfile>".
+ * When "do_newline" is FALSE do not escape newline unless it is csh shell.
+ * Returns the result in allocated memory, NULL if we have run out.
+ */
+    char_u *
+vim_strsave_shellescape(char_u *string, int do_special, int do_newline)
+{
+    unsigned	length;
+    char_u	*p;
+    char_u	*d;
+    char_u	*escaped_string;
+    int		l;
+    int		csh_like;
+    char_u	*shname;
+    int		powershell;
+# ifdef MSWIN
+    int		double_quotes;
+# endif
+
+    // Only csh and similar shells expand '!' within single quotes.  For sh and
+    // the like we must not put a backslash before it, it will be taken
+    // literally.  If do_special is set the '!' will be escaped twice.
+    // Csh also needs to have "\n" escaped twice when do_special is set.
+    csh_like = csh_like_shell();
+
+    // PowerShell uses it's own version for quoting single quotes
+    shname = gettail(p_sh);
+    powershell = strstr((char *)shname, "pwsh") != NULL;
+# ifdef MSWIN
+    powershell = powershell || strstr((char *)shname, "powershell") != NULL;
+    // PowerShell only accepts single quotes so override shellslash.
+    double_quotes = !powershell && !p_ssl;
+# endif
+
+    // First count the number of extra bytes required.
+    length = (unsigned)STRLEN(string) + 3;  // two quotes and a trailing NUL
+    for (p = string; *p != NUL; MB_PTR_ADV(p))
+    {
+# ifdef MSWIN
+	if (double_quotes)
+	{
+	    if (*p == '"')
+		++length;		// " -> ""
+	}
+	else
+# endif
+	if (*p == '\'')
+	{
+	    if (powershell)
+		length +=2;		// ' => ''
+	    else
+		length += 3;		// ' => '\''
+	}
+	if ((*p == '\n' && (csh_like || do_newline))
+		|| (*p == '!' && (csh_like || do_special)))
+	{
+	    ++length;			// insert backslash
+	    if (csh_like && do_special)
+		++length;		// insert backslash
+	}
+	if (do_special && find_cmdline_var(p, &l) >= 0)
+	{
+	    ++length;			// insert backslash
+	    p += l - 1;
+	}
+    }
+
+    // Allocate memory for the result and fill it.
+    escaped_string = alloc(length);
+    if (escaped_string != NULL)
+    {
+	d = escaped_string;
+
+	// add opening quote
+# ifdef MSWIN
+	if (double_quotes)
+	    *d++ = '"';
+	else
+# endif
+	    *d++ = '\'';
+
+	for (p = string; *p != NUL; )
+	{
+# ifdef MSWIN
+	    if (double_quotes)
+	    {
+		if (*p == '"')
+		{
+		    *d++ = '"';
+		    *d++ = '"';
+		    ++p;
+		    continue;
+		}
+	    }
+	    else
+# endif
+	    if (*p == '\'')
+	    {
+		if (powershell)
+		{
+		    *d++ = '\'';
+		    *d++ = '\'';
+		}
+		else
+		{
+		    *d++ = '\'';
+		    *d++ = '\\';
+		    *d++ = '\'';
+		    *d++ = '\'';
+		}
+		++p;
+		continue;
+	    }
+	    if ((*p == '\n' && (csh_like || do_newline))
+		    || (*p == '!' && (csh_like || do_special)))
+	    {
+		*d++ = '\\';
+		if (csh_like && do_special)
+		    *d++ = '\\';
+		*d++ = *p++;
+		continue;
+	    }
+	    if (do_special && find_cmdline_var(p, &l) >= 0)
+	    {
+		*d++ = '\\';		// insert backslash
+		while (--l >= 0)	// copy the var
+		    *d++ = *p++;
+		continue;
+	    }
+
+	    MB_COPY_CHAR(p, d);
+	}
+
+	// add terminating quote and finish with a NUL
+# ifdef MSWIN
+	if (double_quotes)
+	    *d++ = '"';
+	else
+# endif
+	    *d++ = '\'';
+	*d = NUL;
+    }
+
+    return escaped_string;
+}
+
+/*
+ * Like vim_strsave(), but make all characters uppercase.
+ * This uses ASCII lower-to-upper case translation, language independent.
+ */
+    char_u *
+vim_strsave_up(char_u *string)
+{
+    char_u *p1;
+
+    p1 = vim_strsave(string);
+    vim_strup(p1);
+    return p1;
+}
+
+/*
+ * Like vim_strnsave(), but make all characters uppercase.
+ * This uses ASCII lower-to-upper case translation, language independent.
+ */
+    char_u *
+vim_strnsave_up(char_u *string, size_t len)
+{
+    char_u *p1;
+
+    p1 = vim_strnsave(string, len);
+    vim_strup(p1);
+    return p1;
+}
+
+/*
+ * ASCII lower-to-upper case translation, language independent.
+ */
+    void
+vim_strup(
+    char_u	*p)
+{
+    char_u  *p2;
+    int	    c;
+
+    if (p != NULL)
+    {
+	p2 = p;
+	while ((c = *p2) != NUL)
+#ifdef EBCDIC
+	    *p2++ = isalpha(c) ? toupper(c) : c;
+#else
+	    *p2++ = (c < 'a' || c > 'z') ? c : (c - 0x20);
+#endif
+    }
+}
+
+#if defined(FEAT_EVAL) || defined(FEAT_SPELL) || defined(PROTO)
+/*
+ * Make string "s" all upper-case and return it in allocated memory.
+ * Handles multi-byte characters as well as possible.
+ * Returns NULL when out of memory.
+ */
+    static char_u *
+strup_save(char_u *orig)
+{
+    char_u	*p;
+    char_u	*res;
+
+    res = p = vim_strsave(orig);
+
+    if (res != NULL)
+	while (*p != NUL)
+	{
+	    int		l;
+
+	    if (enc_utf8)
+	    {
+		int	c, uc;
+		int	newl;
+		char_u	*s;
+
+		c = utf_ptr2char(p);
+		l = utf_ptr2len(p);
+		if (c == 0)
+		{
+		    // overlong sequence, use only the first byte
+		    c = *p;
+		    l = 1;
+		}
+		uc = utf_toupper(c);
+
+		// Reallocate string when byte count changes.  This is rare,
+		// thus it's OK to do another malloc()/free().
+		newl = utf_char2len(uc);
+		if (newl != l)
+		{
+		    s = alloc(STRLEN(res) + 1 + newl - l);
+		    if (s == NULL)
+		    {
+			vim_free(res);
+			return NULL;
+		    }
+		    mch_memmove(s, res, p - res);
+		    STRCPY(s + (p - res) + newl, p + l);
+		    p = s + (p - res);
+		    vim_free(res);
+		    res = s;
+		}
+
+		utf_char2bytes(uc, p);
+		p += newl;
+	    }
+	    else if (has_mbyte && (l = (*mb_ptr2len)(p)) > 1)
+		p += l;		// skip multi-byte character
+	    else
+	    {
+		*p = TOUPPER_LOC(*p); // note that toupper() can be a macro
+		p++;
+	    }
+	}
+
+    return res;
+}
+
+/*
+ * Make string "s" all lower-case and return it in allocated memory.
+ * Handles multi-byte characters as well as possible.
+ * Returns NULL when out of memory.
+ */
+    char_u *
+strlow_save(char_u *orig)
+{
+    char_u	*p;
+    char_u	*res;
+
+    res = p = vim_strsave(orig);
+
+    if (res != NULL)
+	while (*p != NUL)
+	{
+	    int		l;
+
+	    if (enc_utf8)
+	    {
+		int	c, lc;
+		int	newl;
+		char_u	*s;
+
+		c = utf_ptr2char(p);
+		l = utf_ptr2len(p);
+		if (c == 0)
+		{
+		    // overlong sequence, use only the first byte
+		    c = *p;
+		    l = 1;
+		}
+		lc = utf_tolower(c);
+
+		// Reallocate string when byte count changes.  This is rare,
+		// thus it's OK to do another malloc()/free().
+		newl = utf_char2len(lc);
+		if (newl != l)
+		{
+		    s = alloc(STRLEN(res) + 1 + newl - l);
+		    if (s == NULL)
+		    {
+			vim_free(res);
+			return NULL;
+		    }
+		    mch_memmove(s, res, p - res);
+		    STRCPY(s + (p - res) + newl, p + l);
+		    p = s + (p - res);
+		    vim_free(res);
+		    res = s;
+		}
+
+		utf_char2bytes(lc, p);
+		p += newl;
+	    }
+	    else if (has_mbyte && (l = (*mb_ptr2len)(p)) > 1)
+		p += l;		// skip multi-byte character
+	    else
+	    {
+		*p = TOLOWER_LOC(*p); // note that tolower() can be a macro
+		p++;
+	    }
+	}
+
+    return res;
+}
+#endif
+
+/*
+ * delete spaces at the end of a string
+ */
+    void
+del_trailing_spaces(char_u *ptr)
+{
+    char_u	*q;
+
+    q = ptr + STRLEN(ptr);
+    while (--q > ptr && VIM_ISWHITE(q[0]) && q[-1] != '\\' && q[-1] != Ctrl_V)
+	*q = NUL;
+}
+
+/*
+ * Like strncpy(), but always terminate the result with one NUL.
+ * "to" must be "len + 1" long!
+ */
+    void
+vim_strncpy(char_u *to, char_u *from, size_t len)
+{
+    STRNCPY(to, from, len);
+    to[len] = NUL;
+}
+
+/*
+ * Like strcat(), but make sure the result fits in "tosize" bytes and is
+ * always NUL terminated. "from" and "to" may overlap.
+ */
+    void
+vim_strcat(char_u *to, char_u *from, size_t tosize)
+{
+    size_t tolen = STRLEN(to);
+    size_t fromlen = STRLEN(from);
+
+    if (tolen + fromlen + 1 > tosize)
+    {
+	mch_memmove(to + tolen, from, tosize - tolen - 1);
+	to[tosize - 1] = NUL;
+    }
+    else
+	mch_memmove(to + tolen, from, fromlen + 1);
+}
+
+#if (!defined(HAVE_STRCASECMP) && !defined(HAVE_STRICMP)) || defined(PROTO)
+/*
+ * Compare two strings, ignoring case, using current locale.
+ * Doesn't work for multi-byte characters.
+ * return 0 for match, < 0 for smaller, > 0 for bigger
+ */
+    int
+vim_stricmp(char *s1, char *s2)
+{
+    int		i;
+
+    for (;;)
+    {
+	i = (int)TOLOWER_LOC(*s1) - (int)TOLOWER_LOC(*s2);
+	if (i != 0)
+	    return i;			    // this character different
+	if (*s1 == NUL)
+	    break;			    // strings match until NUL
+	++s1;
+	++s2;
+    }
+    return 0;				    // strings match
+}
+#endif
+
+#if (!defined(HAVE_STRNCASECMP) && !defined(HAVE_STRNICMP)) || defined(PROTO)
+/*
+ * Compare two strings, for length "len", ignoring case, using current locale.
+ * Doesn't work for multi-byte characters.
+ * return 0 for match, < 0 for smaller, > 0 for bigger
+ */
+    int
+vim_strnicmp(char *s1, char *s2, size_t len)
+{
+    int		i;
+
+    while (len > 0)
+    {
+	i = (int)TOLOWER_LOC(*s1) - (int)TOLOWER_LOC(*s2);
+	if (i != 0)
+	    return i;			    // this character different
+	if (*s1 == NUL)
+	    break;			    // strings match until NUL
+	++s1;
+	++s2;
+	--len;
+    }
+    return 0;				    // strings match
+}
+#endif
+
+/*
+ * Search for first occurrence of "c" in "string".
+ * Version of strchr() that handles unsigned char strings with characters from
+ * 128 to 255 correctly.  It also doesn't return a pointer to the NUL at the
+ * end of the string.
+ */
+    char_u  *
+vim_strchr(char_u *string, int c)
+{
+    char_u	*p;
+    int		b;
+
+    p = string;
+    if (enc_utf8 && c >= 0x80)
+    {
+	while (*p != NUL)
+	{
+	    int l = utfc_ptr2len(p);
+
+	    // Avoid matching an illegal byte here.
+	    if (utf_ptr2char(p) == c && l > 1)
+		return p;
+	    p += l;
+	}
+	return NULL;
+    }
+    if (enc_dbcs != 0 && c > 255)
+    {
+	int	n2 = c & 0xff;
+
+	c = ((unsigned)c >> 8) & 0xff;
+	while ((b = *p) != NUL)
+	{
+	    if (b == c && p[1] == n2)
+		return p;
+	    p += (*mb_ptr2len)(p);
+	}
+	return NULL;
+    }
+    if (has_mbyte)
+    {
+	while ((b = *p) != NUL)
+	{
+	    if (b == c)
+		return p;
+	    p += (*mb_ptr2len)(p);
+	}
+	return NULL;
+    }
+    while ((b = *p) != NUL)
+    {
+	if (b == c)
+	    return p;
+	++p;
+    }
+    return NULL;
+}
+
+/*
+ * Version of strchr() that only works for bytes and handles unsigned char
+ * strings with characters above 128 correctly. It also doesn't return a
+ * pointer to the NUL at the end of the string.
+ */
+    char_u  *
+vim_strbyte(char_u *string, int c)
+{
+    char_u	*p = string;
+
+    while (*p != NUL)
+    {
+	if (*p == c)
+	    return p;
+	++p;
+    }
+    return NULL;
+}
+
+/*
+ * Search for last occurrence of "c" in "string".
+ * Version of strrchr() that handles unsigned char strings with characters from
+ * 128 to 255 correctly.  It also doesn't return a pointer to the NUL at the
+ * end of the string.
+ * Return NULL if not found.
+ * Does not handle multi-byte char for "c"!
+ */
+    char_u  *
+vim_strrchr(char_u *string, int c)
+{
+    char_u	*retval = NULL;
+    char_u	*p = string;
+
+    while (*p)
+    {
+	if (*p == c)
+	    retval = p;
+	MB_PTR_ADV(p);
+    }
+    return retval;
+}
+
+/*
+ * Vim's version of strpbrk(), in case it's missing.
+ * Don't generate a prototype for this, causes problems when it's not used.
+ */
+#ifndef PROTO
+# ifndef HAVE_STRPBRK
+#  ifdef vim_strpbrk
+#   undef vim_strpbrk
+#  endif
+    char_u *
+vim_strpbrk(char_u *s, char_u *charset)
+{
+    while (*s)
+    {
+	if (vim_strchr(charset, *s) != NULL)
+	    return s;
+	MB_PTR_ADV(s);
+    }
+    return NULL;
+}
+# endif
+#endif
+
+/*
+ * Sort an array of strings.
+ */
+static int sort_compare(const void *s1, const void *s2);
+
+    static int
+sort_compare(const void *s1, const void *s2)
+{
+    return STRCMP(*(char **)s1, *(char **)s2);
+}
+
+    void
+sort_strings(
+    char_u	**files,
+    int		count)
+{
+    qsort((void *)files, (size_t)count, sizeof(char_u *), sort_compare);
+}
+
+#if defined(FEAT_QUICKFIX) || defined(FEAT_SPELL) || defined(PROTO)
+/*
+ * Return TRUE if string "s" contains a non-ASCII character (128 or higher).
+ * When "s" is NULL FALSE is returned.
+ */
+    int
+has_non_ascii(char_u *s)
+{
+    char_u	*p;
+
+    if (s != NULL)
+	for (p = s; *p != NUL; ++p)
+	    if (*p >= 128)
+		return TRUE;
+    return FALSE;
+}
+#endif
+
+/*
+ * Concatenate two strings and return the result in allocated memory.
+ * Returns NULL when out of memory.
+ */
+    char_u  *
+concat_str(char_u *str1, char_u *str2)
+{
+    char_u  *dest;
+    size_t  l = str1 == NULL ? 0 : STRLEN(str1);
+
+    dest = alloc(l + (str2 == NULL ? 0 : STRLEN(str2)) + 1L);
+    if (dest != NULL)
+    {
+	if (str1 == NULL)
+	    *dest = NUL;
+	else
+	    STRCPY(dest, str1);
+	if (str2 != NULL)
+	    STRCPY(dest + l, str2);
+    }
+    return dest;
+}
+
+#if defined(FEAT_EVAL) || defined(PROTO)
+
+/*
+ * Return string "str" in ' quotes, doubling ' characters.
+ * If "str" is NULL an empty string is assumed.
+ * If "function" is TRUE make it function('string').
+ */
+    char_u *
+string_quote(char_u *str, int function)
+{
+    unsigned	len;
+    char_u	*p, *r, *s;
+
+    len = (function ? 13 : 3);
+    if (str != NULL)
+    {
+	len += (unsigned)STRLEN(str);
+	for (p = str; *p != NUL; MB_PTR_ADV(p))
+	    if (*p == '\'')
+		++len;
+    }
+    s = r = alloc(len);
+    if (r != NULL)
+    {
+	if (function)
+	{
+	    STRCPY(r, "function('");
+	    r += 10;
+	}
+	else
+	    *r++ = '\'';
+	if (str != NULL)
+	    for (p = str; *p != NUL; )
+	    {
+		if (*p == '\'')
+		    *r++ = '\'';
+		MB_COPY_CHAR(p, r);
+	    }
+	*r++ = '\'';
+	if (function)
+	    *r++ = ')';
+	*r++ = NUL;
+    }
+    return s;
+}
+
+    static void
+byteidx(typval_T *argvars, typval_T *rettv, int comp UNUSED)
+{
+    char_u	*t;
+    char_u	*str;
+    varnumber_T	idx;
+
+    str = tv_get_string_chk(&argvars[0]);
+    idx = tv_get_number_chk(&argvars[1], NULL);
+    rettv->vval.v_number = -1;
+    if (str == NULL || idx < 0)
+	return;
+
+    t = str;
+    for ( ; idx > 0; idx--)
+    {
+	if (*t == NUL)		// EOL reached
+	    return;
+	if (enc_utf8 && comp)
+	    t += utf_ptr2len(t);
+	else
+	    t += (*mb_ptr2len)(t);
+    }
+    rettv->vval.v_number = (varnumber_T)(t - str);
+}
+
+/*
+ * "byteidx()" function
+ */
+    void
+f_byteidx(typval_T *argvars, typval_T *rettv)
+{
+    byteidx(argvars, rettv, FALSE);
+}
+
+/*
+ * "byteidxcomp()" function
+ */
+    void
+f_byteidxcomp(typval_T *argvars, typval_T *rettv)
+{
+    byteidx(argvars, rettv, TRUE);
+}
+
+/*
+ * "charidx()" function
+ */
+    void
+f_charidx(typval_T *argvars, typval_T *rettv)
+{
+    char_u	*str;
+    varnumber_T	idx;
+    varnumber_T	countcc = FALSE;
+    char_u	*p;
+    int		len;
+    int		(*ptr2len)(char_u *);
+
+    rettv->vval.v_number = -1;
+
+    if (argvars[0].v_type != VAR_STRING || argvars[1].v_type != VAR_NUMBER
+	    || (argvars[2].v_type != VAR_UNKNOWN
+					   && argvars[2].v_type != VAR_NUMBER
+					   && argvars[2].v_type != VAR_BOOL))
+    {
+	emsg(_(e_invarg));
+	return;
+    }
+
+    str = tv_get_string_chk(&argvars[0]);
+    idx = tv_get_number_chk(&argvars[1], NULL);
+    if (str == NULL || idx < 0)
+	return;
+
+    if (argvars[2].v_type != VAR_UNKNOWN)
+	countcc = tv_get_bool(&argvars[2]);
+    if (countcc < 0 || countcc > 1)
+    {
+	semsg(_(e_using_number_as_bool_nr), countcc);
+	return;
+    }
+
+    if (enc_utf8 && countcc)
+	ptr2len = utf_ptr2len;
+    else
+	ptr2len = mb_ptr2len;
+
+    for (p = str, len = 0; p <= str + idx; len++)
+    {
+	if (*p == NUL)
+	    return;
+	p += ptr2len(p);
+    }
+
+    rettv->vval.v_number = len > 0 ? len - 1 : 0;
+}
+
+/*
+ * "str2list()" function
+ */
+    void
+f_str2list(typval_T *argvars, typval_T *rettv)
+{
+    char_u	*p;
+    int		utf8 = FALSE;
+
+    if (rettv_list_alloc(rettv) == FAIL)
+	return;
+
+    if (argvars[1].v_type != VAR_UNKNOWN)
+	utf8 = (int)tv_get_bool_chk(&argvars[1], NULL);
+
+    p = tv_get_string(&argvars[0]);
+
+    if (has_mbyte || utf8)
+    {
+	int (*ptr2len)(char_u *);
+	int (*ptr2char)(char_u *);
+
+	if (utf8 || enc_utf8)
+	{
+	    ptr2len = utf_ptr2len;
+	    ptr2char = utf_ptr2char;
+	}
+	else
+	{
+	    ptr2len = mb_ptr2len;
+	    ptr2char = mb_ptr2char;
+	}
+
+	for ( ; *p != NUL; p += (*ptr2len)(p))
+	    list_append_number(rettv->vval.v_list, (*ptr2char)(p));
+    }
+    else
+	for ( ; *p != NUL; ++p)
+	    list_append_number(rettv->vval.v_list, *p);
+}
+
+/*
+ * "str2nr()" function
+ */
+    void
+f_str2nr(typval_T *argvars, typval_T *rettv)
+{
+    int		base = 10;
+    char_u	*p;
+    varnumber_T	n;
+    int		what = 0;
+    int		isneg;
+
+    if (argvars[1].v_type != VAR_UNKNOWN)
+    {
+	base = (int)tv_get_number(&argvars[1]);
+	if (base != 2 && base != 8 && base != 10 && base != 16)
+	{
+	    emsg(_(e_invarg));
+	    return;
+	}
+	if (argvars[2].v_type != VAR_UNKNOWN && tv_get_bool(&argvars[2]))
+	    what |= STR2NR_QUOTE;
+    }
+
+    p = skipwhite(tv_get_string_strict(&argvars[0]));
+    isneg = (*p == '-');
+    if (*p == '+' || *p == '-')
+	p = skipwhite(p + 1);
+    switch (base)
+    {
+	case 2: what |= STR2NR_BIN + STR2NR_FORCE; break;
+	case 8: what |= STR2NR_OCT + STR2NR_OOCT + STR2NR_FORCE; break;
+	case 16: what |= STR2NR_HEX + STR2NR_FORCE; break;
+    }
+    vim_str2nr(p, NULL, NULL, what, &n, NULL, 0, FALSE);
+    // Text after the number is silently ignored.
+    if (isneg)
+	rettv->vval.v_number = -n;
+    else
+	rettv->vval.v_number = n;
+
+}
+
+/*
+ * "strgetchar()" function
+ */
+    void
+f_strgetchar(typval_T *argvars, typval_T *rettv)
+{
+    char_u	*str;
+    int		len;
+    int		error = FALSE;
+    int		charidx;
+    int		byteidx = 0;
+
+    rettv->vval.v_number = -1;
+    str = tv_get_string_chk(&argvars[0]);
+    if (str == NULL)
+	return;
+    len = (int)STRLEN(str);
+    charidx = (int)tv_get_number_chk(&argvars[1], &error);
+    if (error)
+	return;
+
+    while (charidx >= 0 && byteidx < len)
+    {
+	if (charidx == 0)
+	{
+	    rettv->vval.v_number = mb_ptr2char(str + byteidx);
+	    break;
+	}
+	--charidx;
+	byteidx += MB_CPTR2LEN(str + byteidx);
+    }
+}
+
+/*
+ * "stridx()" function
+ */
+    void
+f_stridx(typval_T *argvars, typval_T *rettv)
+{
+    char_u	buf[NUMBUFLEN];
+    char_u	*needle;
+    char_u	*haystack;
+    char_u	*save_haystack;
+    char_u	*pos;
+    int		start_idx;
+
+    needle = tv_get_string_chk(&argvars[1]);
+    save_haystack = haystack = tv_get_string_buf_chk(&argvars[0], buf);
+    rettv->vval.v_number = -1;
+    if (needle == NULL || haystack == NULL)
+	return;		// type error; errmsg already given
+
+    if (argvars[2].v_type != VAR_UNKNOWN)
+    {
+	int	    error = FALSE;
+
+	start_idx = (int)tv_get_number_chk(&argvars[2], &error);
+	if (error || start_idx >= (int)STRLEN(haystack))
+	    return;
+	if (start_idx >= 0)
+	    haystack += start_idx;
+    }
+
+    pos	= (char_u *)strstr((char *)haystack, (char *)needle);
+    if (pos != NULL)
+	rettv->vval.v_number = (varnumber_T)(pos - save_haystack);
+}
+
+/*
+ * "string()" function
+ */
+    void
+f_string(typval_T *argvars, typval_T *rettv)
+{
+    char_u	*tofree;
+    char_u	numbuf[NUMBUFLEN];
+
+    rettv->v_type = VAR_STRING;
+    rettv->vval.v_string = tv2string(&argvars[0], &tofree, numbuf,
+								get_copyID());
+    // Make a copy if we have a value but it's not in allocated memory.
+    if (rettv->vval.v_string != NULL && tofree == NULL)
+	rettv->vval.v_string = vim_strsave(rettv->vval.v_string);
+}
+
+/*
+ * "strlen()" function
+ */
+    void
+f_strlen(typval_T *argvars, typval_T *rettv)
+{
+    rettv->vval.v_number = (varnumber_T)(STRLEN(
+					      tv_get_string(&argvars[0])));
+}
+
+    static void
+strchar_common(typval_T *argvars, typval_T *rettv, int skipcc)
+{
+    char_u		*s = tv_get_string(&argvars[0]);
+    varnumber_T		len = 0;
+    int			(*func_mb_ptr2char_adv)(char_u **pp);
+
+    func_mb_ptr2char_adv = skipcc ? mb_ptr2char_adv : mb_cptr2char_adv;
+    while (*s != NUL)
+    {
+	func_mb_ptr2char_adv(&s);
+	++len;
+    }
+    rettv->vval.v_number = len;
+}
+
+/*
+ * "strcharlen()" function
+ */
+    void
+f_strcharlen(typval_T *argvars, typval_T *rettv)
+{
+    strchar_common(argvars, rettv, TRUE);
+}
+
+/*
+ * "strchars()" function
+ */
+    void
+f_strchars(typval_T *argvars, typval_T *rettv)
+{
+    varnumber_T		skipcc = FALSE;
+
+    if (argvars[1].v_type != VAR_UNKNOWN)
+	skipcc = tv_get_bool(&argvars[1]);
+    if (skipcc < 0 || skipcc > 1)
+	semsg(_(e_using_number_as_bool_nr), skipcc);
+    else
+	strchar_common(argvars, rettv, skipcc);
+}
+
+/*
+ * "strdisplaywidth()" function
+ */
+    void
+f_strdisplaywidth(typval_T *argvars, typval_T *rettv)
+{
+    char_u	*s = tv_get_string(&argvars[0]);
+    int		col = 0;
+
+    if (argvars[1].v_type != VAR_UNKNOWN)
+	col = (int)tv_get_number(&argvars[1]);
+
+    rettv->vval.v_number = (varnumber_T)(linetabsize_col(col, s) - col);
+}
+
+/*
+ * "strwidth()" function
+ */
+    void
+f_strwidth(typval_T *argvars, typval_T *rettv)
+{
+    char_u	*s = tv_get_string_strict(&argvars[0]);
+
+    rettv->vval.v_number = (varnumber_T)(mb_string2cells(s, -1));
+}
+
+/*
+ * "strcharpart()" function
+ */
+    void
+f_strcharpart(typval_T *argvars, typval_T *rettv)
+{
+    char_u	*p;
+    int		nchar;
+    int		nbyte = 0;
+    int		charlen;
+    int		skipcc = FALSE;
+    int		len = 0;
+    int		slen;
+    int		error = FALSE;
+
+    p = tv_get_string(&argvars[0]);
+    slen = (int)STRLEN(p);
+
+    nchar = (int)tv_get_number_chk(&argvars[1], &error);
+    if (!error)
+    {
+	if (argvars[2].v_type != VAR_UNKNOWN
+					   && argvars[3].v_type != VAR_UNKNOWN)
+	{
+	    skipcc = tv_get_bool(&argvars[3]);
+	    if (skipcc < 0 || skipcc > 1)
+	    {
+		semsg(_(e_using_number_as_bool_nr), skipcc);
+		return;
+	    }
+	}
+
+	if (nchar > 0)
+	    while (nchar > 0 && nbyte < slen)
+	    {
+		if (skipcc)
+		    nbyte += mb_ptr2len(p + nbyte);
+		else
+		    nbyte += MB_CPTR2LEN(p + nbyte);
+		--nchar;
+	    }
+	else
+	    nbyte = nchar;
+	if (argvars[2].v_type != VAR_UNKNOWN)
+	{
+	    charlen = (int)tv_get_number(&argvars[2]);
+	    while (charlen > 0 && nbyte + len < slen)
+	    {
+		int off = nbyte + len;
+
+		if (off < 0)
+		    len += 1;
+		else
+		{
+		    if (skipcc)
+			len += mb_ptr2len(p + off);
+		    else
+			len += MB_CPTR2LEN(p + off);
+		}
+		--charlen;
+	    }
+	}
+	else
+	    len = slen - nbyte;    // default: all bytes that are available.
+    }
+
+    /*
+     * Only return the overlap between the specified part and the actual
+     * string.
+     */
+    if (nbyte < 0)
+    {
+	len += nbyte;
+	nbyte = 0;
+    }
+    else if (nbyte > slen)
+	nbyte = slen;
+    if (len < 0)
+	len = 0;
+    else if (nbyte + len > slen)
+	len = slen - nbyte;
+
+    rettv->v_type = VAR_STRING;
+    rettv->vval.v_string = vim_strnsave(p + nbyte, len);
+}
+
+/*
+ * "strpart()" function
+ */
+    void
+f_strpart(typval_T *argvars, typval_T *rettv)
+{
+    char_u	*p;
+    int		n;
+    int		len;
+    int		slen;
+    int		error = FALSE;
+
+    p = tv_get_string(&argvars[0]);
+    slen = (int)STRLEN(p);
+
+    n = (int)tv_get_number_chk(&argvars[1], &error);
+    if (error)
+	len = 0;
+    else if (argvars[2].v_type != VAR_UNKNOWN)
+	len = (int)tv_get_number(&argvars[2]);
+    else
+	len = slen - n;	    // default len: all bytes that are available.
+
+    // Only return the overlap between the specified part and the actual
+    // string.
+    if (n < 0)
+    {
+	len += n;
+	n = 0;
+    }
+    else if (n > slen)
+	n = slen;
+    if (len < 0)
+	len = 0;
+    else if (n + len > slen)
+	len = slen - n;
+
+    if (argvars[2].v_type != VAR_UNKNOWN && argvars[3].v_type != VAR_UNKNOWN)
+    {
+	int off;
+
+	// length in characters
+	for (off = n; off < slen && len > 0; --len)
+	    off += mb_ptr2len(p + off);
+	len = off - n;
+    }
+
+    rettv->v_type = VAR_STRING;
+    rettv->vval.v_string = vim_strnsave(p + n, len);
+}
+
+/*
+ * "strridx()" function
+ */
+    void
+f_strridx(typval_T *argvars, typval_T *rettv)
+{
+    char_u	buf[NUMBUFLEN];
+    char_u	*needle;
+    char_u	*haystack;
+    char_u	*rest;
+    char_u	*lastmatch = NULL;
+    int		haystack_len, end_idx;
+
+    needle = tv_get_string_chk(&argvars[1]);
+    haystack = tv_get_string_buf_chk(&argvars[0], buf);
+
+    rettv->vval.v_number = -1;
+    if (needle == NULL || haystack == NULL)
+	return;		// type error; errmsg already given
+
+    haystack_len = (int)STRLEN(haystack);
+    if (argvars[2].v_type != VAR_UNKNOWN)
+    {
+	// Third argument: upper limit for index
+	end_idx = (int)tv_get_number_chk(&argvars[2], NULL);
+	if (end_idx < 0)
+	    return;	// can never find a match
+    }
+    else
+	end_idx = haystack_len;
+
+    if (*needle == NUL)
+    {
+	// Empty string matches past the end.
+	lastmatch = haystack + end_idx;
+    }
+    else
+    {
+	for (rest = haystack; *rest != '\0'; ++rest)
+	{
+	    rest = (char_u *)strstr((char *)rest, (char *)needle);
+	    if (rest == NULL || rest > haystack + end_idx)
+		break;
+	    lastmatch = rest;
+	}
+    }
+
+    if (lastmatch == NULL)
+	rettv->vval.v_number = -1;
+    else
+	rettv->vval.v_number = (varnumber_T)(lastmatch - haystack);
+}
+
+/*
+ * "strtrans()" function
+ */
+    void
+f_strtrans(typval_T *argvars, typval_T *rettv)
+{
+    rettv->v_type = VAR_STRING;
+    rettv->vval.v_string = transstr(tv_get_string(&argvars[0]));
+}
+
+/*
+ * "tolower(string)" function
+ */
+    void
+f_tolower(typval_T *argvars, typval_T *rettv)
+{
+    rettv->v_type = VAR_STRING;
+    rettv->vval.v_string = strlow_save(tv_get_string(&argvars[0]));
+}
+
+/*
+ * "toupper(string)" function
+ */
+    void
+f_toupper(typval_T *argvars, typval_T *rettv)
+{
+    rettv->v_type = VAR_STRING;
+    rettv->vval.v_string = strup_save(tv_get_string(&argvars[0]));
+}
+
+/*
+ * "tr(string, fromstr, tostr)" function
+ */
+    void
+f_tr(typval_T *argvars, typval_T *rettv)
+{
+    char_u	*in_str;
+    char_u	*fromstr;
+    char_u	*tostr;
+    char_u	*p;
+    int		inlen;
+    int		fromlen;
+    int		tolen;
+    int		idx;
+    char_u	*cpstr;
+    int		cplen;
+    int		first = TRUE;
+    char_u	buf[NUMBUFLEN];
+    char_u	buf2[NUMBUFLEN];
+    garray_T	ga;
+
+    in_str = tv_get_string(&argvars[0]);
+    fromstr = tv_get_string_buf_chk(&argvars[1], buf);
+    tostr = tv_get_string_buf_chk(&argvars[2], buf2);
+
+    // Default return value: empty string.
+    rettv->v_type = VAR_STRING;
+    rettv->vval.v_string = NULL;
+    if (fromstr == NULL || tostr == NULL)
+	    return;		// type error; errmsg already given
+    ga_init2(&ga, (int)sizeof(char), 80);
+
+    if (!has_mbyte)
+	// not multi-byte: fromstr and tostr must be the same length
+	if (STRLEN(fromstr) != STRLEN(tostr))
+	{
+error:
+	    semsg(_(e_invarg2), fromstr);
+	    ga_clear(&ga);
+	    return;
+	}
+
+    // fromstr and tostr have to contain the same number of chars
+    while (*in_str != NUL)
+    {
+	if (has_mbyte)
+	{
+	    inlen = (*mb_ptr2len)(in_str);
+	    cpstr = in_str;
+	    cplen = inlen;
+	    idx = 0;
+	    for (p = fromstr; *p != NUL; p += fromlen)
+	    {
+		fromlen = (*mb_ptr2len)(p);
+		if (fromlen == inlen && STRNCMP(in_str, p, inlen) == 0)
+		{
+		    for (p = tostr; *p != NUL; p += tolen)
+		    {
+			tolen = (*mb_ptr2len)(p);
+			if (idx-- == 0)
+			{
+			    cplen = tolen;
+			    cpstr = p;
+			    break;
+			}
+		    }
+		    if (*p == NUL)	// tostr is shorter than fromstr
+			goto error;
+		    break;
+		}
+		++idx;
+	    }
+
+	    if (first && cpstr == in_str)
+	    {
+		// Check that fromstr and tostr have the same number of
+		// (multi-byte) characters.  Done only once when a character
+		// of in_str doesn't appear in fromstr.
+		first = FALSE;
+		for (p = tostr; *p != NUL; p += tolen)
+		{
+		    tolen = (*mb_ptr2len)(p);
+		    --idx;
+		}
+		if (idx != 0)
+		    goto error;
+	    }
+
+	    (void)ga_grow(&ga, cplen);
+	    mch_memmove((char *)ga.ga_data + ga.ga_len, cpstr, (size_t)cplen);
+	    ga.ga_len += cplen;
+
+	    in_str += inlen;
+	}
+	else
+	{
+	    // When not using multi-byte chars we can do it faster.
+	    p = vim_strchr(fromstr, *in_str);
+	    if (p != NULL)
+		ga_append(&ga, tostr[p - fromstr]);
+	    else
+		ga_append(&ga, *in_str);
+	    ++in_str;
+	}
+    }
+
+    // add a terminating NUL
+    (void)ga_grow(&ga, 1);
+    ga_append(&ga, NUL);
+
+    rettv->vval.v_string = ga.ga_data;
+}
+
+/*
+ * "trim({expr})" function
+ */
+    void
+f_trim(typval_T *argvars, typval_T *rettv)
+{
+    char_u	buf1[NUMBUFLEN];
+    char_u	buf2[NUMBUFLEN];
+    char_u	*head = tv_get_string_buf_chk(&argvars[0], buf1);
+    char_u	*mask = NULL;
+    char_u	*tail;
+    char_u	*prev;
+    char_u	*p;
+    int		c1;
+    int		dir = 0;
+
+    rettv->v_type = VAR_STRING;
+    rettv->vval.v_string = NULL;
+    if (head == NULL)
+	return;
+
+    if (argvars[1].v_type != VAR_UNKNOWN && argvars[1].v_type != VAR_STRING)
+    {
+	semsg(_(e_invarg2), tv_get_string(&argvars[1]));
+	return;
+    }
+
+    if (argvars[1].v_type == VAR_STRING)
+    {
+	mask = tv_get_string_buf_chk(&argvars[1], buf2);
+
+	if (argvars[2].v_type != VAR_UNKNOWN)
+	{
+	    int	error = 0;
+
+	    // leading or trailing characters to trim
+	    dir = (int)tv_get_number_chk(&argvars[2], &error);
+	    if (error)
+		return;
+	    if (dir < 0 || dir > 2)
+	    {
+		semsg(_(e_invarg2), tv_get_string(&argvars[2]));
+		return;
+	    }
+	}
+    }
+
+    if (dir == 0 || dir == 1)
+    {
+	// Trim leading characters
+	while (*head != NUL)
+	{
+	    c1 = PTR2CHAR(head);
+	    if (mask == NULL)
+	    {
+		if (c1 > ' ' && c1 != 0xa0)
+		    break;
+	    }
+	    else
+	    {
+		for (p = mask; *p != NUL; MB_PTR_ADV(p))
+		    if (c1 == PTR2CHAR(p))
+			break;
+		if (*p == NUL)
+		    break;
+	    }
+	    MB_PTR_ADV(head);
+	}
+    }
+
+    tail = head + STRLEN(head);
+    if (dir == 0 || dir == 2)
+    {
+	// Trim trailing characters
+	for (; tail > head; tail = prev)
+	{
+	    prev = tail;
+	    MB_PTR_BACK(head, prev);
+	    c1 = PTR2CHAR(prev);
+	    if (mask == NULL)
+	    {
+		if (c1 > ' ' && c1 != 0xa0)
+		    break;
+	    }
+	    else
+	    {
+		for (p = mask; *p != NUL; MB_PTR_ADV(p))
+		    if (c1 == PTR2CHAR(p))
+			break;
+		if (*p == NUL)
+		    break;
+	    }
+	}
+    }
+    rettv->vval.v_string = vim_strnsave(head, tail - head);
+}
+
+#endif
diff --git a/src/version.c b/src/version.c
--- a/src/version.c
+++ b/src/version.c
@@ -756,6 +756,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3139,
+/**/
     3138,
 /**/
     3137,