# [OS X TeX] LaTeX macro question

J. McKenzie Alexander jalex at lse.ac.uk
Wed Feb 8 12:25:23 EST 2012

Hello,

I'm trying to write an environment that does the following things: (1) saves the verbatim text between the \begin and \end commands as a list of tokens, (2) computes a simple hash function on that token list to generate a value (so as to be able to detect when the content changes), and (3) uses \scantokens to re-process that list of tokens so as to typeset it "properly".

Right now, I'm having problems with (1) and (3) — I just can't seem to figure out how to save the verbatim text and then process it with \scantokens.

I know the following lets me save verbatim text:

\usepackage{fancyvrb}

\begin{SaveVerbatim}{asdf}
\begin{tikzpicture}
\draw (0,0) -- (0,1) -- (1,1) -- cycle;
\end{tikzpicture}
\end{SaveVerbatim}

And now I can typeset that as many times as I want via \UseVerbatim{asdf}.

But

\scantokens{\UseVerbatim{asdf}}

Just reproduces the same output as \UseVerbatim{asdf}

and

\expandafter\scantokens\expandafter{\UseVerbatim{asdf}}

produces an error.

Any suggestions would be most appreciated!

Cheers,

Jason

--
Dr J. McKenzie Alexander
Department of Philosophy, Logic and Scientific Method
London School of Economics and Political Science
Houghton Street, London WC2A 2AE

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