From: Bart Schaefer <schaefer@brasslantern.com>
To: zsh-users@zsh.org
Subject: Re: Catch `setopt nounset`
Date: Thu, 9 Apr 2015 11:42:05 -0700 [thread overview]
Message-ID: <150409114205.ZM25276@torch.brasslantern.com> (raw)
In-Reply-To: <mg69er$i52$1@ger.gmane.org>
On Apr 9, 6:30pm, Thorsten Kampe wrote:
}
} I'd to catch the call of a parameter that does not exist with `setopt
} nounset`.
setopt nounset
{
print "$DOESNOTEXIST"
} always {
if (( TRY_BLOCK_ERROR ))
then print "error"
else print "no error"
fi
}
} If I replace the `catch` statement with `if result=$(testfunc)` it
} prints "error". What am I missing here? Why does the latter work but
} not the former?
"parameter not set" is a fatal error, so whatever the current shell is
doing is stopped when that happens. $(testfunc) is run in a subshell,
so the current shell proceeds even though the subshell died.
You could get the same result with
if ( testfunc )
then
printf "no error\n"
else
printf "error\n"
fi
but of course that also suppresses all other side-effects of "testfunc",
which the "always" construct will not.
next prev parent reply other threads:[~2015-04-09 18:42 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-09 16:30 Thorsten Kampe
2015-04-09 18:42 ` Bart Schaefer [this message]
2015-04-10 1:11 ` Thorsten Kampe
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