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unravel --- Watching TeX digest tokens
E-mail: blflatex@gmail.com
Released under the LaTeX Project Public License v1.3c or later
See http://www.latex-project.org/lppl.txt
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The unravel LaTeX package provides tools to explore TeX code,
performing expansion and assignments step by step.

TeX is a strange beast. Its eyes read files, making characters
into tokens. Its mouth then chews tokens, expanding them if
possible, namely, expanding user-defined macros, or conditionals,
etc. When meeting a so called ``unexpandable'' token, TeX's
stomach comes into play, performing assignments, or moving boxes
around, eventually typesetting the result thanks to its great
line- and page-breaking algorithms.

All of this is interleaved, and difficult to follow. Of course,
one can always use \tracingall, but the result is... messy.
This package is an attempt to replicate how TeX digests tokens,
and to make the process easier to follow. Namely,
\unravel{\some\tokens} will let you go through expansions and
assignments performed by TeX upon seeing of ``\some\tokens'',
step by step.

Some parts of TeX are not covered. In particular, category codes
are fixed for the whole argument of \unravel when it is read.

This package requires up-to-date versions of the l3kernel,
l3packages, and l3experimental bundles.

The package is extracted by running "pdflatex unravel.ins".
For documentation, run "pdflatex unravel.dtx" twice.