typeset question

typeset question

[Bernd Eggink]

I'm confused... These two statements work fine and give the same
results:

	typeset x=(a b c)

	x=($(cat file))

where file contains the lines 

	a
	b
	c

But this one does _not_ work:

	typeset x=($(cat file))
Output:
	zsh: not an identifier: c)

Am I missing something or is this a bug? If it's a bug, it's there at
least since 3.0.2

Bernd

--
Bernd Eggink
Regionales Rechenzentrum der Uni Hamburg
eggink@rrz.uni-hamburg.de
http://www.rrz.uni-hamburg.de/eggink/BEggink.html

Re: typeset question

[Peter Stephenson]

Bernd Eggink wrote:
> I'm confused... These two statements work fine and give the same
> results:
> 
> 	typeset x=(a b c)
> 
> 	x=($(cat file))

Actually, the first is not an array assignment; there is nothing
syntactically special about the parentheses in a typeset statement.
(In fact, it does grouping in all statements, to make globs using
parentheses work sensibly, which is why the spaces don't separate words,
but even so typeset just gets the string `x=(a b c)').  You should find
x contains the string '(a b c)'.

> But this one does _not_ work:
> 
> 	typeset x=($(cat file))
> Output:
> 	zsh: not an identifier: c)

As the outer (...) is not special, the $(cat file) splits the thing
into three arguments: x=(a, b and c).  typeset complains about the last
one.

The fix is to do `typeset x' first, then the array assignment to x in
a separate statement.

-- 
Peter Stephenson <pws@ifh.de>       Tel: +49 33762 77366
WWW:  http://www.ifh.de/~pws/       Fax: +49 33762 77413
Deutsches Elektronen-Synchrotron --- Institut fuer Hochenergiephysik Zeuthen
DESY-IfH, Platanenallee 6, 15738 Zeuthen, Germany.

Re: typeset question

[Bernd Eggink]

Peter Stephenson wrote:
> 
> Bernd Eggink wrote:
> > I'm confused... These two statements work fine and give the same
> > results:
> >
> >       typeset x=(a b c)
> >
> >       x=($(cat file))
> 
> Actually, the first is not an array assignment; there is nothing
> syntactically special about the parentheses in a typeset statement.
> (In fact, it does grouping in all statements, to make globs using
> parentheses work sensibly, which is why the spaces don't separate words,
> but even so typeset just gets the string `x=(a b c)').  You should find
> x contains the string '(a b c)'.

My confusion was caused by a curious property of 'typeset'. If the
variable 
is already defined as a normal variable, and if it is an array, typeset 
does _nothing_. In all other cases it works as expected. Try this:

	x=a
	typeset x=b	
	print $x	# prints: b

OK... Now try

	unset x
	x=(a b c)
	typeset x=(x y z)
	print $x	# prints: a b c

The contents of the brace gets evaluated, but no assignment takes place.
Bug or 
feature? It's not documented nor does it make sense to me. 

--
Bernd Eggink
Regionales Rechenzentrum der Uni Hamburg
eggink@rrz.uni-hamburg.de
http://www.rrz.uni-hamburg.de/eggink/BEggink.html