%%
%% The LaTeX Companion, 2ed (second printing August 2004)
%%
%% Example 3-4-42 on page 175.
%%
%% 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{listings}
\StopShownPreambleCommands
\begin{document}
\lstset{literate={:=}{{$\gets$}}1
 {<=}{{$\leq$}}1 {>=}{{$\geq$}}1 {<>}{{$\neq$}}1}
\begin{lstlisting}[gobble=2]
  var i:integer;
  if (i<=0) i := 1;
  if (i>=0) i := 0;
  if (i<>0) i := 0;
\end{lstlisting}
\end{document}