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Variations on the `\expandafter` TeX primitive
==============================================
* E-mail: blflatex@gmail.com
* Released under the LaTeX Project Public License v1.3c or later
See http://www.latex-project.org/lppl.txt
Every TeX programmer knows `\expandafter`, and how messy it can become
when trying to expand several times a very deeply hidden token. For
example, say we want to expand `\C` four times before `\A` and `\B` in
`\A\B\C`. The traditional approach would be to insert 15 `\expandafter`
before `\A` and the same number before `\B`. This package allows the two
simpler codes
\expandafter\A\expandafter\B\romannumeral\multiexpand{4}\C
or
\expandafter\A\romannumeral\multiexpandafter{4}\B\C
In one step of expansion (triggered by the `\expandafter`'s), the
sequence `\romannumeral\multiexpand{4}` expands the following token 4
times, whereas `\romannumeral\multiexpandafter{4}` expands the token
after that 4 times.
The code behaves with braces as `\expandafter` would. Another example is
\MultiExpandAfter{2}\a\MultiExpandAfter{3}{%
\MultiExpandAfter{10}\b\MultiExpandAfter{10}\c\d},
which expands `\d` 10 times, then `\c` 8 times, then `\b` once.
The whole process will only take two steps of expansion.
The package can be built from the file `multiexpand.dtx' by running
pdflatex multiexpand.dtx
pdflatex multiexpand.dtx
pdflatex multiexpand-example.tex
The last step is optional: it runs a series of tests.
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