At 19:32 +0100 1998/11/06, Marcel Oliver wrote:
>Question: how difficult would it be to extend TeX to
>allow for dual/multiple tier expansion?  What are the draw-backs?

(I leave to somebody else more qualified to respond to your particular idea.)

For the general problems with TeX one must rely on more general mechanisms
to solve them.

>So precisely why do you think
>one needs to distinguish "authoring semantics", "typesetting style" and

It depends on how far one wants to go: On the more general side, one would
work through the different movements with TeX/LaTeX, SGML, etc, isolate the
semantic components, define runtime object which can be used by the
Lex/Yacc parts to define a local syntactic module. A rather major
undertaking. :-)

  Hans Aberg
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