this works great---well, I stole it right out of the docs:
{
\catcode`!=\active
\begin{Verbatim}[defineactive=\def!{\color{red}\bf}]
black
! red
black
\end{Verbatim}
}
now I would like to have multiple active characters, each designating a particular style. I could bore everyone with my code that tries to generalize this to two or three characters (define '-' as active, then add another defineactive with a comma), but they were all wrong.
is this easy?
a related question (not needed) is whether one can easy switch forth and back on the same line.
advice appreciated.
