%%
%% The LaTeX Companion, 2ed (second printing August 2004)
%%
%% Example 5-1-4 on page 242.
%%
%% 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{207.0pt}
\StartShownPreambleCommands
\newcommand\lenrule[1]{\makebox[#1]{%
  \rule{.4pt}{4pt}\hrulefill\rule{.4pt}{4pt}}}
\StopShownPreambleCommands
\begin{document}
\begin{tabbing}
dd\quad \= \hspace{.55\linewidth} \= \kill
pc  \> Pica = 12pt \> \lenrule{1pc} \\
cc  \> Cicero  = 12dd \> \lenrule{1cc} \\
cm  \> Centimeter = 10mm \> \lenrule{1cm} \\
\end{tabbing}
\end{document}
