To escape many _ in LaTeX efficiently

Question

How can you escape _ without the use of \_?

This is the example of the question

word_a_a_a_a_a_b_c_dd

There is one function which you can use for this. However, I cannot remember its name.

Eschar

Answer 1

Are you thinking of the underscore package, which redefines the underscore symbol so that you don't have to escape it in text mode? See here.

Justino

Thank you for pointing that out! I will use this package in my next procject, since my current code breaks because it contains a lot of underscores espaces by \_. – Locate

Answer 2

Other than verbatim I wouldn't know.

Verbatim environment:

\begin{verbatim}
  word_a_a_a_a_a_b_c_dd
\end{verbatim}

Inline:

\verb|word_a_a_a_a_a_b_c_dd|

Sateen

A problem is that this doesn't work inside many things, like \item[\verb|here|] is illegal. See this answer for an alternative tex.stackexchange.com/a/2252/15665 I use \usepackage[Q=yes,pverb-linebreak=no]{examplep} and \item[\Q{this_works}] – Kaczmarek

Answer 3

I couldn't get the underscore package to work, so I used the url package:

\usepackage{url}
\urlstyle{sf}  % or rm, depending on your font

...

Foo \url{word_a_a_a_a_a_b_c_dd} bar.

Vanwinkle

Only issue here is that if you define the color of your urls elsewhere in the preamble, this will make them colored. – Degeneracy

Answer 4

It's funny how this is a question and answer site for programming questions but nobody has suggested programming yet.

You could define your own command which replaces the underscore tokens:

\documentclass{article}

\newcommand{\filename}[1]{\emph{\replunderscores{#1}}}

\makeatletter
% \expandafter for the case that the filename is given in a command
\newcommand{\replunderscores}[1]{\expandafter\@repl@underscores#1_\relax}

\def\@repl@underscores#1_#2\relax{%
    \ifx \relax #2\relax
        % #2 is empty => finish
        #1%
    \else
        % #2 is not empty => underscore was contained, needs to be replaced
        #1%
        \textunderscore
        % continue replacing
        % #2 ends with an extra underscore so I don't need to add another one
        \@repl@underscores#2\relax
    \fi
}
\makeatother


\begin{document}
    \filename{__init__.py}
\end{document}

Pistoleer

Thank you for this answer, this is precisely what I needed. I wanted to define a command to add an URL in a footnote but keeping a regular font. \newcommand{\footurl}[1]{\footnote{\href{#1}{\replunderscores{#1}}}} – Distasteful

@Distasteful I'm glad if my answer has helped you. Please keep in mind, though, that URLs can contain other characters where this approach does not work like % or #. So you may not always get around changing catcodes and simply speaking that does not work inside of arguments. The url package makes it easy to define a macro containing the URL where this is possible and then use the macro inside of the footnote without changing fonts if you wish so: \urlstyle{same} ... \urldef{\myurl}\url{some%url#} ... \footnote{see \myurl} – Pistoleer

Answer 5

Typically you want a monospaced font in such situations, so you can use this:

\verb|word_a_a_a_a_a_b_c_dd|

Thou

Answer 6

You may also be thinking of the lstlisting or verbatim environments, which are commonly used to display code - which can contain underscores. However, these environments do a lot more than just "escape" underscores.

Yuyuan

Answer 7

Most methods above fail when the text comes from another macro, because one does not want to list the macro name. The \url{} command works, but if one does not want a link generated, then one can use also \nolinkurl{} from the hyperref package.

For example you could use the macro \jobname to print the base name of your main LaTeX file. This will print some funny characters in place of the underscores, if the filename contains underscores. To print the filename properly, you could wrap the macro \jobname in \nolinkurl.

For example, if the filename is "my_project.tex" you could:

1. add \usepackage{hyperref} to the preamble.
2. use \nolinkurl{\jobname} to print the filename "my_project" in your document.

Admittedly, this is not a good answer to the original question on how to escape many underscores, since you won't be able to put a long text in \nolinkurl.

Guileful

Please add some code to show how to implement your solution. – Ermaermanno