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Message-ID:  <4B750AD0.4070302@morningstar2.co.uk>
Date:         Fri, 12 Feb 2010 08:01:20 +0000
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From: Joseph Wright <joseph.wright@MORNINGSTAR2.CO.UK>
Subject: Re: Scratch variables
To: LATEX-L@listserv.uni-heidelberg.de
In-Reply-To:  <FF9BC9F2-D33A-4051-82A7-8A78DEFD8469@gmail.com>
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Status: R

On 12/02/2010 00:35, Will Robertson wrote:
> On 12/02/2010, at 5:56 AM, Joseph Wright wrote:
>
>> On 11/02/2010 18:26, Philipp Stephani wrote:
>>>
>>> I wonder what the guarantees about the scratch variables like \l_tmpa_tl are. The documentation just states that "they are not used by conditionals or predicate functions." Does this mean that any other kernel macro might modify them?
>>
>> A quick search shows they are used in the tl module. I'd stick to defining "private" scratch variables.
>
> Should we change this?
> I.e., use \l_kernel_tmpa_tl or \l_reserveda_tl instead for us and let package writers use \l_tmpa_tl ?
>
> -- Will
>
I think we probably should: the documentation seems to imply that they 
are available, and it would be best if there was clear demarcation.
-- 
Joseph Wright