From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCHv5 16/16] Introduce portable_unset and use it to ensure
 proper && chaining
Date: Sun, 3 Oct 2010 09:51:22 -0500
Message-ID: <20101003145122.GF17084@burratino>
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To: Elijah Newren <newren@gmail.com>
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Elijah Newren wrote:

> --- a/t/test-lib.sh
> +++ b/t/test-lib.sh
> @@ -268,6 +268,10 @@ remove_cr () {
>  	tr '\015' Q | sed -e 's/Q$//'
>  }
>  
> +portable_unset () {
> +	unset $* || true
> +}

I think this should read

	portable_unset () {
		unset "$@"
		return 0
	}

(or || true).  That is, if I try

	portable_unset "foo bar"

then on platforms where an envvar named "foo bar" is allowed,
this should unset it, no?

Also, maybe a comment could guide people in using this:

	# In some bourne shell implementations, the "unset" builtin
	# returns nonzero status when a variable to be unset was not
	# set in the first place.
	#
	# Use portable_unset when that should not be considered an
	# error.

An update to t/README would be nice, too. :)