From mboxrd@z Thu Jan 1 00:00:00 1970 From: "David A. Wheeler" Subject: Re: [PATCH] Allow == as synonym for = in test Date: Sun, 06 Mar 2011 20:12:29 -0500 (EST) Message-ID: References: <20110306234845.GC18385@elie> Reply-To: dwheeler@dwheeler.com Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: Received: from aibo.runbox.com ([87.238.52.70]:35589 "EHLO aibo.runbox.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753266Ab1CGBMb convert rfc822-to-8bit (ORCPT ); Sun, 6 Mar 2011 20:12:31 -0500 Content-Disposition: inline In-Reply-To: <20110306234845.GC18385@elie> Sender: dash-owner@vger.kernel.org List-Id: dash@vger.kernel.org To: dash@vger.kernel.org, jrnieder@gmail.com Jonathan Nieder: > Has the Austin Group made a decision > on whether this syntax is going to be supported? I don't think a decision has been formally made. Most of the email discussion has been about possibly adding "<" and ">" to the spec, which are not in the current POSIX spec but are already implemented in dash. The last comment posted on mantis about this extension to POSIX was positive; eblake (manager) said, "adding the other four operators (==, -ot, -nt, -ef) make[s] sense" [http://austingroupbugs.net/view.php?id=375]. > dash tends to support features that ash and older > versions of dash supported (to avoid breaking backward compatibility) Busybox's ash *already* supports "==", so I think that's *also* an argument for adding "==". After all, adding "==" would improve compatibility between busybox ash and dash, and its effect on space and speed is miniscule. I understand that dash wants to be "lean and mean", but busybox does too, and even busybox supports "==". I think it's reasonably likely that "==" will be added to the POSIX spec, but that's not up to me. Even if this syntax isn't added to the official standard, I still think it'd make sense to support "==". It's already implemented in a number of shells, including bash, busybox ash, and ksh. More importantly, a lot of extant shell scripts use it; many scripts won't work on dash because dash doesn't include "==". --- David A. Wheeler