Re: [help-texinfo] Typing rules in Texinfo manual

[Karl Berry]

Hi Stefan - indeed, fractions a la \frac have never been supported in
Texinfo.  Or display math, or all kinds of other things.

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I'm not sure what kind of input you are hoping for.  But I fear that
this is a case where using @macro (or m4/other preprocessor macros,
except apparently nobody except me ever liked that idea) is the best
option.  Yes, you'd have to write different macro bodies for TeX, HTML,
Info[, Docbook, XML].

There will surely be plenty of problems, but I can't think of any other
approach, unless Gavin feels like adding a new @frac{num,den} (or
whatever) command, and you want to use a brand-new command in your
source ...

As for the general concept of "typing rules", I don't understand.  It's
not possible to document "X in LaTeX is equivalent to Y in Texinfo" for
the simple reason that only a tiny fraction ( :) of LaTeX is in Texinfo.
By design.  And anyway the purpose of the Texinfo manual is to document
Texinfo, not LaTeX.  But I know you already know all this, so I suppose
you must mean something else ...

Best,
Karl