Empty array and parameter expansion

Empty array and parameter expansion

[Vincent Lefevre]

I don't understand the following behavior (with zsh 3.0.5):

% i=test
% a=()
% a=($a $i)
% echo $a
$i

I would have thought that "test" would be printed.
Is it a bug or a strange feature?

-- 
Vincent Lefevre <Vincent.Lefevre@ens-lyon.fr> - PhD stud. in Computer Science
Web: http://www.ens-lyon.fr/~vlefevre/ - 100% validated HTML - Acorn Risc PC,
Yellow Pig 17, Championnat International des Jeux Mathematiques et Logiques,
TETRHEX, Faits divers insolites, etc...

Re: Empty array and parameter expansion

[Vincent Lefevre]

On Wed, Jun 10, 1998 at 10:26:51 -0700, Bart Schaefer wrote:
> } % i=test
> } % a=()
> } % a=($a $i)
> } % echo $a
> } $i
> 
> I don't understand it either, as it doesn't happen to me.

After some tests... it happens only when RC_EXPAND_PARAM is set.
But is it normal?

-- 
Vincent Lefevre <Vincent.Lefevre@ens-lyon.fr> - PhD stud. in Computer Science
Web: http://www.ens-lyon.fr/~vlefevre/ - 100% validated HTML - Acorn Risc PC,
Yellow Pig 17, Championnat International des Jeux Mathematiques et Logiques,
TETRHEX, Faits divers insolites, etc...

Re: Empty array and parameter expansion

[Bart Schaefer]

On Jun 10, 11:36pm, Vincent Lefevre wrote:
> Subject: Re: Empty array and parameter expansion
> On Wed, Jun 10, 1998 at 10:26:51 -0700, Bart Schaefer wrote:
> > } % i=test
> > } % a=()
> > } % a=($a $i)
> > } % echo $a
> > } $i
> > 
> > I don't understand it either, as it doesn't happen to me.
> 
> After some tests... it happens only when RC_EXPAND_PARAM is set.
> But is it normal?

You want this patch, from zsh-workers article 3548 last November:

Index: subst.c
===================================================================
--- subst.c	1997/11/19 16:40:31	1.6
+++ subst.c	1997/11/19 16:44:41	1.7
@@ -1440,7 +1440,7 @@
 	    }
 	    if (plan9) {
 		uremnode(l, n);
-		return NULL;
+		return n;
 	    }
 	} else {
 	    x = aval[0];