%%
%% The LaTeX Companion, 3ed
%%
%% Example 4-2-16 on page I-307 in "Customization keys for typesetting".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{183.0pt}

%StartShownPreambleCommands
\usepackage{fancyvrb}
%StopShownPreambleCommands

\begin{document}
\begin{itemize}  \item  Normal indentation left:
  \begin{Verbatim}[frame=single,xrightmargin=2pc]
A long line of verbatim text!
  \end{Verbatim}
  \item No indentation at either side:
  \begin{Verbatim}[resetmargins=true,
                   frame=single]
A long line of verbatim text!
  \end{Verbatim}
\end{itemize}
\end{document}