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From: Anthony Heading <aheading@jpmorgan.com>
Message-Id: <199611270920.JAA24482@et-sun4.uk.jpmorgan.com>
Subject: Is ${} supported?
To: zsh-workers@math.gatech.edu
Date: Wed, 27 Nov 1996 09:20:41 +0000 (GMT)
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The "null" parameter seems useful to allow the following sort of thing:

% echo ${(j/+/):-{one,two,three}}
one+two+three

But does it only work by accident, or can it be relied on?  Should
it be documented?

Anthony