# How to break a very long line?

I am using a lstinputlisting to read text from an external file.

\lstinputlisting[breaklines]{text.txt}


The file contains a very long line:

ssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringgggggggggggggggggggggggg ssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringgggggggggggggggggggggggg ssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringgggggggggggggggggggggggg ssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringgggggggggggggggggggggggg ssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringgggggggggggggggggggggggg ssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringgggggggggggggggggggggggg ssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringgggggggggggggggggggggggg ssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringggggggggggggggggggggggggssssssssssssssssssssssssssstrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrringgggggggggggggggggggggggg


I would like the line to break into several consecutive lines, but it shows a "Dimension too large" error.

• Thank you for posting a working example! At the same time, much of your code does not seem to be relevant to the question you're asking here. Please limit the example to only the code required for your issue to appear. You can have a look at this guide for how to prune your code for this purpose. – Stefan Pinnow Aug 1 '18 at 18:51
• Are the strings you posted in the code block above for real? – Mico Aug 1 '18 at 19:11
• If this is all that is contained within the file, consider this option: How to break long words after n chars (long genomic sequences) – Werner Aug 1 '18 at 19:14
• Werner, the answers posted there include the string in the code instead of reading it from a file. – Marcelo Henrique Bittencourt Aug 1 '18 at 19:50
• @MarceloHenriqueBittencourt: You can capture the contents of a file in a macro (using catchfile) and use that... – Werner Aug 1 '18 at 20:58

I found a solution based on the comments to my question:

\documentclass{article}
\usepackage{listings}
\makeatletter
\def\@tempA#1#2\@end
{
\@tempA@{#1}
\ifx\relax#2\relax
\else\@tempA#2\@end
\fi
}
\def\@tempA@#1
{
{\noexpand#1}
{{\char\noexpand#1\allowbreak}}1
}
\edef\@tempB
{
\noexpand\lstdefinelanguage{text}
{
keepspaces,
breaklines,
literate=\@tempA !"\#\$\%\&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_abcdefghijklmnopqrstuvwxyz\{|\}~\@end } } \@tempB \makeatother \newlength\basewidth \settowidth\basewidth{\ttfamily\tiny X} \lstset { language=text, basicstyle=\ttfamily\tiny, basewidth=\basewidth, breakindent=4\basewidth, postbreak=\llap{$\hookrightarrow\$}
}
\begin{document}
\lstinputlisting{text.txt}
\end{document}


The solution was based primarily on this answer. I do not know exactly how the code above works, but it works.

Curiously, that approach still does not work if the line is too big, i.e., if the line spans two or more pages. In that case, the error "Dimension too large" is still shown. A possible workaround for that is decreasing font size and page margins so that the line would fit in less than two pages, although it is not a perfect solution.