PATCH: 3.1.5-pws-6: vared and associative arrays

["Bart Schaefer" <schaefer@brasslantern.com>]

The following patch makes vared do reasonable things with associative arrays.
Using vared on an associative array edits a string consisting of all the keys
and values of the array; the string is then split at spaces and assigned as
alternating keys and values.

Put another way:

	vared array	is to	print -z "array=( ${array} )"
as
	vared assoc	is to	print -z "assoc=( ${(kv)assoc} )"

The patch also adds two new options, -a and -A, which are only interesting
when used with -c.  `vared -ca array` creates an array parameter, and (as
you might expect) `vared -cA assoc` creates an associative array parameter.

There is one change here that might be controversial.  Using `vared -ca`
on an existing parameter whose type is not array converts it into an array.
Similarly, `vared -cA` converts to an associative array.  Plain `vared -c`
still does not change the type of existing parameters, so no existing uses
should be broken by this.

Finally, vared can now be used to edit individual elements of arrays and
associative arrays, like so:

zsh% array=(this is an array)
zsh% noglob vared array[-1]
array				<== here type C-a ESC-u RET
zsh% echo $array
this is an ARRAY
zsh% noglob vared array[8]
				<== here type E I G H T RET
zsh$ echo $#array $array
8 this is an ARRAY EIGHT

Note that you don't have to use -c to create new elements, and that it's
an error to use -ca or -cA when editing elements.

I'd have included some of those examples in the manual, but I couldn't
decide on the correct yodl incantation.

(BTW, you can even edit array slices this way; but due to limitations on
my understanding of the parameter code, the whole array is inserted into
the editor buffer, and whatever's left when you press return is correctly
assigned to the slice.)

The one other change to this patch is to move a test for recursive ZLE up
to the top of the function; there's no point in parsing the args if the
whole thing is goig to bail anyway.

Have fun.

Index: Doc/Zsh/mod_zle.yo
===================================================================
RCS file: /extra/cvsroot/zsh/zsh-3.1/Doc/Zsh/mod_zle.yo,v
retrieving revision 1.4
diff -u -r1.4 mod_zle.yo
--- mod_zle.yo	1999/01/26 05:23:21	1.4
+++ mod_zle.yo	1999/01/31 20:34:24
@@ -131,12 +131,20 @@
 findex(vared)
 cindex(parameters, editing)
 cindex(editing parameters)
-item(tt(vared) [ tt(-ch) ] [ tt(-p) var(prompt) ] [ tt(-r) var(rprompt) ] var(name))(
+item(tt(vared) [ tt(-Aach) ] [ tt(-p) var(prompt) ] [ tt(-r) var(rprompt) ] var(name))(
 The value of the parameter var(name) is loaded into the edit
 buffer, and the line editor is invoked.  When the editor exits,
 var(name) is set to the string value returned by the editor.
-If the tt(-c) flag is given, the parameter is created if it doesn't
-already exist.
+When the tt(-c) flag is given, the parameter is created if it doesn't
+already exist.  The tt(-a) flag may be given with tt(-c) to create
+an array parameter, or the tt(-A) flag to create an associative array.
+If the type of an existing parameter does not match the type to be
+created, the parameter is unset and recreated.
+
+Individual elements of existing array or associative array parameters
+may be edited by using subscript syntax on var(name).  New elements are
+created automatically, even without tt(-c).
+
 If the tt(-p) flag is given, the following string will be taken as
 the prompt to display at the left.  If the tt(-r) flag is given,
 the following string gives the prompt to display at the right.  If the
Index: Src/Zle/zle_main.c
===================================================================
RCS file: /extra/cvsroot/zsh/zsh-3.1/Src/Zle/zle_main.c,v
retrieving revision 1.12
diff -u -r1.12 zle_main.c
--- zle_main.c	1999/01/29 17:24:07	1.12
+++ zle_main.c	1999/01/31 20:13:55
@@ -674,10 +674,17 @@
 {
     char *s;
     char *t;
-    Param pm;
+    Value v;
+    Param pm = 0;
     int create = 0;
+    int type = PM_SCALAR;
     char *p1 = NULL, *p2 = NULL;
 
+    if (zleactive) {
+	zwarnnam(name, "ZLE cannot be used recursively (yet)", NULL, 0);
+	return 1;
+    }
+
     /* all options are handled as arguments */
     while (*args && **args == '-') {
 	while (*++(*args))
@@ -687,6 +694,12 @@
 		yet exist */
 		create = 1;
 		break;
+	    case 'a':
+		type = PM_ARRAY;
+		break;
+	    case 'A':
+		type = PM_HASHED;
+		break;
 	    case 'p':
 		/* -p option -- set main prompt string */
 		if ((*args)[1])
@@ -722,6 +735,9 @@
 	    }
 	args++;
     }
+    if (type && !create) {
+	zwarnnam(name, "-%s ignored", type == PM_ARRAY ? "a" : "A", 0);
+    }
 
     /* check we have a parameter name */
     if (!*args) {
@@ -729,17 +745,17 @@
 	return 1;
     }
     /* handle non-existent parameter */
-    if (!(s = getsparam(args[0]))) {
-	if (create)
-	    createparam(args[0], PM_SCALAR);
-	else {
-	    zwarnnam(name, "no such variable: %s", args[0], 0);
-	    return 1;
-	}
-    }
-
-    if(zleactive) {
-	zwarnnam(name, "ZLE cannot be used recursively (yet)", NULL, 0);
+    s = args[0];
+    v = fetchvalue(&s, (!create || type == PM_SCALAR),
+		   SCANPM_WANTKEYS|SCANPM_WANTVALS|SCANPM_MATCHMANY);
+    if (!v && !create) {
+	zwarnnam(name, "no such variable: %s", args[0], 0);
+	return 1;
+    } else if (v) {
+	s = getstrvalue(v);
+	pm = v->pm;
+    } else if (*s) {
+	zwarnnam(name, "invalid parameter name: %s", args[0], 0);
 	return 1;
     }
 
@@ -757,14 +773,24 @@
     if (t[strlen(t) - 1] == '\n')
 	t[strlen(t) - 1] = '\0';
     /* final assignment of parameter value */
-    pm = (Param) paramtab->getnode(paramtab, args[0]);
-    if (pm && PM_TYPE(pm->flags) == PM_ARRAY) {
+    if (create && (!pm || (type && PM_TYPE(pm->flags) != type))) {
+	if (pm)
+	    unsetparam(args[0]);
+	createparam(args[0], type);
+	pm = 0;
+    }
+    if (!pm)
+	pm = (Param) paramtab->getnode(paramtab, args[0]);
+    if (pm && (PM_TYPE(pm->flags) & (PM_ARRAY|PM_HASHED))) {
 	char **a;
 
 	PERMALLOC {
 	    a = spacesplit(t, 1);
 	} LASTALLOC;
-	setaparam(args[0], a);
+	if (PM_TYPE(pm->flags) == PM_ARRAY)
+	    setaparam(args[0], a);
+	else
+	    sethparam(args[0], a);
     } else
 	setsparam(args[0], t);
     return 0;

-- 
Bart Schaefer                                 Brass Lantern Enterprises
http://www.well.com/user/barts              http://www.brasslantern.com