From: Peter Stephenson <p.stephenson@samsung.com>
To: Zsh Hackers' List <zsh-workers@zsh.org>
Subject: Re: Strange parameter visibility
Date: Thu, 29 Sep 2016 18:03:01 +0100 [thread overview]
Message-ID: <20160929180301.5d1930d0@pwslap01u.europe.root.pri> (raw)
In-Reply-To: <20160929172417.5022a014@pwslap01u.europe.root.pri>
On Thu, 29 Sep 2016 17:24:17 +0100
Peter Stephenson <p.stephenson@samsung.com> wrote:
> This isn't an optimisation gone awry --- we just plain miss out on
> checking that the LHS of the pipeline is supposed to run in the shell so
> we need to fork to do that, as we do in other cases.
This appears to be harder.
% unset x
% : ${x:=2} | echo $x
2
In this case, we don't know at the point where we start the pipeline
whether we're going to be in the current shell or not. If the command
is external we want to keep the current code (not sure where this gets
hairy otherwise but it does).
Other cases people find are likely to be similar to this one.
pws
next prev parent reply other threads:[~2016-09-29 17:03 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20160917181339eucas1p24d214aa618aa96b5a8ddfbf351598da6@eucas1p2.samsung.com>
[not found] ` <87bmzmtmzq.fsf@alfa.kjonca>
[not found] ` <831b307a-a00f-1df7-5136-17fcb769ccaf@gmx.com>
[not found] ` <CAH+w=7YtacLo6aY9gT5V27xYbh-wz0Tot1kbPxBiWN1ZXpavRA@mail.gmail.com>
2016-09-18 4:55 ` Bart Schaefer
2016-09-29 16:24 ` Peter Stephenson
2016-09-29 17:03 ` Peter Stephenson [this message]
2016-09-29 21:28 ` Bart Schaefer
2016-09-29 21:36 ` Bart Schaefer
2016-09-30 8:50 ` Peter Stephenson
2016-09-30 9:36 ` Peter Stephenson
2016-09-30 13:50 ` Peter Stephenson
2016-09-30 19:06 ` Bart Schaefer
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