From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <zsh-workers-return-26299-mason-zsh=primenet.com.au@sunsite.dk>
Received: (qmail 2234 invoked from network); 13 Jan 2009 07:32:51 -0000
X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on f.primenet.com.au
X-Spam-Level: 
X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00 autolearn=ham
	version=3.2.5
Received: from news.dotsrc.org (HELO a.mx.sunsite.dk) (130.225.247.88)
  by ns1.primenet.com.au with SMTP; 13 Jan 2009 07:32:51 -0000
Received-SPF: none (ns1.primenet.com.au: domain at sunsite.dk does not designate permitted sender hosts)
Received: (qmail 60496 invoked from network); 13 Jan 2009 07:32:46 -0000
Received: from sunsite.dk (130.225.247.90)
  by a.mx.sunsite.dk with SMTP; 13 Jan 2009 07:32:46 -0000
Received: (qmail 16177 invoked by alias); 13 Jan 2009 07:32:42 -0000
Mailing-List: contact zsh-workers-help@sunsite.dk; run by ezmlm
Precedence: bulk
X-No-Archive: yes
X-Seq: 26299
Received: (qmail 16164 invoked from network); 13 Jan 2009 07:32:42 -0000
Received: from bifrost.dotsrc.org (130.225.254.106)
  by sunsite.dk with SMTP; 13 Jan 2009 07:32:42 -0000
Received: from QMTA05.westchester.pa.mail.comcast.net (qmta05.westchester.pa.mail.comcast.net [76.96.62.48])
	by bifrost.dotsrc.org (Postfix) with ESMTP id 7680580271F0
	for <zsh-workers@sunsite.dk>; Tue, 13 Jan 2009 08:32:35 +0100 (CET)
Received: from OMTA07.westchester.pa.mail.comcast.net ([76.96.62.59])
	by QMTA05.westchester.pa.mail.comcast.net with comcast
	id 2vRw1b00C1GhbT855vYbhw; Tue, 13 Jan 2009 07:32:35 +0000
Received: from smtp.klanderman.net ([98.217.254.247])
	by OMTA07.westchester.pa.mail.comcast.net with comcast
	id 2vYb1b00A5M2Np63TvYbZE; Tue, 13 Jan 2009 07:32:35 +0000
Received: from lwm.klanderman.net (unknown [192.168.100.50])
	by smtp.klanderman.net (Postfix) with ESMTP id 4CCDAB30144
	for <zsh-workers@sunsite.dk>; Tue, 13 Jan 2009 02:32:34 -0500 (EST)
Received: by lwm.klanderman.net (Postfix, from userid 500)
	id 222A49FC5E5; Tue, 13 Jan 2009 02:32:34 -0500 (EST)
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Message-ID: <18796.17298.94642.461735@gargle.gargle.HOWL>
Date: Tue, 13 Jan 2009 02:32:34 -0500
From: Greg Klanderman <gak@klanderman.net>
To: Zsh list <zsh-workers@sunsite.dk>
Subject: treatment of empty strings - why is this not a bug?
Reply-To: gak@klanderman.net
X-Mailer: VM 7.17 under 21.4 (patch 17) "Jumbo Shrimp" XEmacs Lucid
X-Virus-Scanned: ClamAV 0.92.1/8856/Mon Jan 12 17:36:19 2009 on bifrost
X-Virus-Status: Clean

It's so nice that zsh doesn't do splitting on unquoted parameter
expansions:

[~] greg@lwm| zsh -f
lwm% function count () { echo $# }
lwm% a=( "a b" "c d" )
lwm% echo $#a[@]
2
lwm% count $a[@]
2
lwm% count "$a[@]"
2

however, it does silently drop empty strings:

lwm% a=( "" "" "" )
lwm% echo $#a[@] 
3
lwm% count $a[@]
0
lwm% count "$a[@]"
3

which means you still have to use all those quotes anyway.

I just don't understand why there should be any distinction
between the splitting and dropping of empty strings.

And even using quotes, zsh's treatment of empty strings here
seems very inconsistent:

lwm% x=::: && for v in "${(s-:-)x}" ; do echo "v= =>$v<=" ; done
v= =><=
v= =><=
lwm% x=:a:b: && for v in "${(s-:-)x}" ; do echo "v= =>$v<=" ; done 
v= =><=
v= =>a<=
v= =>b<=
v= =><=

thanks,
Greg