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Message-ID:  <4DAE0235.1020602@morningstar2.co.uk>
Date:         Tue, 19 Apr 2011 22:44:21 +0100
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From: Joseph Wright <joseph.wright@MORNINGSTAR2.CO.UK>
Subject: Re: The nature of popping from an empty sequence
To: LATEX-L@listserv.uni-heidelberg.de
In-Reply-To:  <19886.69.963610.143806@morse.mittelbach-online.de>
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Status: R

On 19/04/2011 22:36, Frank Mittelbach wrote:
> Bruno Le Floch writes:
>  > > Within xtemplate, you'll find some places where we use the fact that the
>  > > keys do have catcodes to pull off some 'special effects'. Now, we also
>  > > remove spaces there, so spaces can also be used for said 'special
>  > > effects'. But such a change would require some alterations.
>  > 
>  > Ok, so my assumption was wrong. But really, playing with catcodes is evil
>  > ;-).
> 
> right and that was a fairly recent change in implementation, wasn't it. It
> might be worth while rethinking if we limit the nature of keys and their
> comparison even if we have to modify the xtemplate code for it

I'd have to check the detail, but from memory this was the most
convenient way to store the key order within the template itself. There
is nothing to stop us moving it back out again to a dedicated location.
-- 
Joseph Wright