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Message-ID:  <4A7ADC50.9000700@morningstar2.co.uk>
Date:         Thu, 6 Aug 2009 14:36:16 +0100
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From: Joseph Wright <joseph.wright@MORNINGSTAR2.CO.UK>
Subject: Re: xparse
To: LATEX-L@LISTSERV.UNI-HEIDELBERG.DE
In-Reply-To:  <4A7A726F.3080006@morningstar2.co.uk>
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Status: R

I wrote:
>>> Is that a yes or no to my "harmless character sequences"? These can
>>> handle data like URLs which might prompt people to go verbatim, but
>>> they aren't implemented using \catcode changes.
>> Not sure I understand -- even URLs need to sanitise % if they're used
>> within an argument.
> 
> I'm with Will: I'm not sure I follow :-(

Okay, I looked at the xdoc2 code and have some feel for what you mean, I
hope. I assume we are talking about \MakeHarmless, and applying it to
the input.  I can see that the space handling there is very careful, but
I wonder what other differences there are between doing \MakeHarmless
and using \detokenize (noting as Will has done that things like % have
to be handled as full-verbatim due to the nested-macro issue).
-- 
Joseph Wright