%%
%% The LaTeX Companion, 3ed
%%
%% Example 4-1-18 on page I-270 in "The placement of the item label or item text".
%%
%% 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{177.0pt}


  \addtolength\textwidth{-25pt}  % account for protrusion into left margin

  \usepackage{microtype} % to improve h&j


%StartShownPreambleCommands
\usepackage{enumitem}
\setlist[itemize]{format=\bfseries}
\SetLabelAlign{rightextend}{\hfill#1}
%StopShownPreambleCommands

\begin{document}
\noindent A sample text showing the outer margins.
\begin{itemize}
\item             Label fits the available space.
\item[Wide label] Label is wider than the available
 space so protrudes into the left margin.\end{itemize}

\begin{itemize}[align=rightextend]
\item             No change to the default.
\item[Wide label] But now wide labels move following
 text partly to the right.               \end{itemize}

\begin{itemize}[align=parleft]
\item[Wide label] A rather ugly example for the use of
 the \texttt{parleft} alignment.         \end{itemize}
\end{document}