Path: utzoo!attcan!uunet!mcsun!unido!fauern!tumuc!lan!weiske
From: weiske@lan.informatik.tu-muenchen.dbp.de (Thomas Weiske)
Newsgroups: comp.text.tex
Subject: Do something special in verbatim
Keywords: LaTeX, verbatim
Message-ID: <2852@tuminfo1.lan.informatik.tu-muenchen.dbp.de>
Date: 13 Jun 90 13:59:20 GMT
Sender: news@lan.informatik.tu-muenchen.dbp.de
Reply-To: weiske@lan.informatik.tu-muenchen.dbp.de (Thomas Weiske)
Organization: Technische Universitaet Muenchen
Lines: 18

Here is a macro, that allows you to escape verbatim
mode and to call macros.  The idea is to define
a new command char, for example '@', that is not
used in the verbatim environment.

% \beginspecial\begin{verbatim} ... verb @macro... \end{verbatim}\endspecial
\def\beginspecial{\catcode`@=0}
\def\endspecial{\catcode`@=12}

Grammar with bold tokens
\def\bebecoms{$\rightarrow$}
\beginspecial\begin{verbatim}
       while_stat @bebecoms @bf while @tt cond @bf do @tt stat_list @bf od @tt
       stat_list  @bebecoms  stat ; stat_list
				  |
\end{verbatim}\endspecial

I think the idea is old but not too bad.