From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [PATCH 1/6] Remote helper: accept ':<value> <name>' as a
 response to 'list'
Date: Mon, 4 Oct 2010 21:00:35 -0500
Message-ID: <20101005020035.GA10818@burratino>
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 <1286108511-55876-1-git-send-email-tom@dbservice.com>
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Cc: git@vger.kernel.org, Sverre Rabbelier <srabbelier@gmail.com>,
	David Michael Barr <david.barr@cordelta.com>,
	Ramkumar Ramachandra <artagnon@gmail.com>
To: Tomas Carnecky <tom@dbservice.com>
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Hi,

Tomas Carnecky wrote:

>                                                          The ref is first stored
> as 'impure', meaning that it doesn't have any representation within git. Only
> after the remote helper fetches that version into git, it can tell us which
> git object (SHA1) that revision maps to.

Hmm.

The existing ls-remote output looks something like

	<object id>	HEAD
	<object id>	<refname>
	<object id>	<refname>
	...
	<object id>	<tag refname>
	<object id>	<tag refname>^{}
	...

In particular, each line has a 40-character object id, a tab character,
and then something like a refname.

If we want to extend that, wouldn't we need to do something like

	0000...0000	<refname>
	0000...0000	<refname> is r11

to avoid breaking people's scripts?  For example, I wouldn't be surprised
if scripts are relying on the following two properties:

 - each object id is 40 characters (e.g., the old fetch--tool
   in contrib/examples relies on this)
 - each object id contains no whitespace

simply because they are convenient to script with.