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Date:         Tue, 16 Sep 2008 06:56:12 +0100
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From: Joseph Wright <joseph.wright@MORNINGSTAR2.CO.UK>
Subject: Re: Generic quark test
To: LATEX-L@LISTSERV.UNI-HEIDELBERG.DE
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Status: R

Will Robertson wrote:
> Hi,
> 
> I've been thinking more about this.
> Just so we're clear, what you're looking for is a function that can be
> given a token list and return true or false depending if, without
> expansion, the list contains a quark.

I was thinking on a much less grand scale.  Currently, you can test if
tlp contains a quark (usually q_no_value).  However, the moment you
create a second quark to indicate something else (lets say
q_value_required) you always need two tests.  If you have more
possibilities, the number of tests rises.  Of course, you are probably
using these quarks separately, but in some places you may need a simple
"Is it a quark? yes/no" test.

My thinking is that trying to see if a tlp contains a quark + something
else is a bit too complicated.  It is really down to the programmer to
watch for that.
-- 
Joseph Wright