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Date: Sat, 26 Sep 2015 13:18:39 +0300
From: Dmitri Vereshchagin <dmitri.vereshchagin@gmail.com>
To: Zsh Users <zsh-users@zsh.org>
Subject: question about parameter expansion
Message-ID: <20150926101839.GA14021@gmail.com>
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User-Agent: Mutt/1.5.24 (2015-08-30)

Hello.

Here is a code sample I would like to rewrite using parameter expansion

  if (( ${+foo} )); then
    bar=
  else
    bar=baz
  fi

Cannot find it in the docs, but I suppose there is a way to do that.  Am
I right?

Thanks.

-- 
Dmitri Vereshchagin