%%
%% The LaTeX Companion, 3ed
%%
%% Example A-5-8 on page II-692 in "ifthen --- Advanced control structures".
%%
%% 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{171.0pt}
%StartShownPreambleCommands
\usepackage{ifthen}  \newcounter{howoften}
%StopShownPreambleCommands

\begin{document}
\setcounter{howoften}{1}
\whiledo{\value{howoften}<5}{I should not talk
     during seminar (\thehowoften).
     \stepcounter{howoften}}
\end{document}