At 13:13 +0000 1998/11/03, David Carlisle wrote:
>and then the question is do you expand before or after testing.
>
>in \quote{this}\foo
>
>do you expand \foo first in case it is defined to start with a , ?
>
>If you decide no then sometimes your quote command will sometimes make
>the wrong decision (this is what xspace does)
>
>If you expand once (by inserting some \expandafter s at suitable places
>then your quote command will make the wrong decision at slightly
>different set of times.

  This problem should be resolved (in principle) by clearly defining what
input syntax LaTeX can accept. The problem is of course that TeX does not
provide a mechanism checking that the input syuntax is correct. So it may
prove difficult to do it in practise within the current TeX.

  Hans Aberg
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