%%
%% The LaTeX Companion, 2ed (second printing August 2004)
%%
%% Example 3-4-10 on page 157.
%%
%% Copyright (C) 2004 Frank Mittelbach, Michel Goossens,
%%    Johannes Braams, David Carlisle, and Chris Rowley
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3
%% of this license or (at your option) any later version.
%%
%% See http://www.latex-project.org/lppl.txt for details.
%%

\documentclass{ttctexa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{183.0pt}

\StartShownPreambleCommands
\usepackage{ifthen,color,fancyvrb}
\StopShownPreambleCommands
\begin{document}
\renewcommand\FancyVerbFormatLine[1]
  {\ifthenelse{\isodd{\value{FancyVerbLine}}}%
              {\textcolor{blue}{#1}}{#1}}
\begin{Verbatim}[gobble=2]
  This line should become blue while
   this one will be black. And here
you can observe that gobble removes
not only blanks but any character.
\end{Verbatim}
\end{document}
