From: Peter Stephenson <p.w.stephenson@ntlworld.com>
To: Patrick Reader <zsh578@pxeger.com>, zsh-workers@zsh.org
Subject: Re: Bug with assignments in some commands
Date: Mon, 18 Jan 2021 16:34:23 +0000 (GMT) [thread overview]
Message-ID: <1219668732.3070481.1610987664058@mail2.virginmedia.com> (raw)
In-Reply-To: <0102017716203d60-ea3cd78f-867c-4f6e-b37b-583ccdb44c13-000000@eu-west-1.amazonses.com>
> On 18 January 2021 at 15:32 Patrick Reader <zsh578@pxeger.com> wrote:
> I believe I have found a bug: in arithmetic $(( )) or $[ ] and variable
> expansions ${ } in some forms of command (pipelines, command
> substitutions, and inside here-documents and here-strings are the cases
> I know of so far), assignments to variables do not persist outside the
> command, almost as if it were in a subshell.
They *are* in a subshell. That's just how the shell works.
The only difference between zsh and other shells is that some other shells
run the left hand of a pipeline rather than the right hand of a pipeline
in the current shell (if it's shell code, of course), but that's not
something you can rely on. There is a patch floating around for
a compatibility mode, but in native zsh mode running the right hand
of a pipeline in the current shell, and hence the other parts in
subshells, is a feature.
pws
next prev parent reply other threads:[~2021-01-18 16:34 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-18 15:32 Patrick Reader
2021-01-18 16:34 ` Peter Stephenson [this message]
2021-01-18 17:40 ` Bart Schaefer
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