6

My code:

\documentclass{article}
\usepackage{listings}
\usepackage{xcolor}
\lstset{
    language=[latex]tex,
    basicstyle=\ttfamily,
    commentstyle=\color{violet},
    columns=fullflexible,
    keepspaces=true,
    upquote=true,
    showstringspaces=false,
}
\begin{document}
\begin{lstlisting}
Foo % Comment 1
Bar % Comment 2
Baz \% Not a comment
\end{lstlisting}
\end{document}

Output:

enter image description here

Why is % Not a comment colored violet when it is not a comment? How can I fix this?

Improve this question
2
  • Inside lstlisting environment, backslash character \ is just a normal character, so \% is not interpreted as a command anymore. What other contents will you use inside that lstlisting environment?
    – muzimuzhi Z
    Jun 6, 2020 at 1:00
  • 1
    @muzimuzhiZ Isn't it a bug in lstlisting then? When I have mentioned [latex]tex as the language, shouldn't it use LaTeX grammar parsing rules for all content in lstlisting environment? I mean, Vim gets it right and does not highlight \% Not a comment as a comment. Shouldn't lstlisting do the same thing?
    – Lone Learner
    Jun 6, 2020 at 7:18

3 Answers 3

Reset to default
2
+25

you can try to setup the \% as a string:

\documentclass{article}
\usepackage{listings}
\usepackage{xcolor}
\lstset{
    language=[latex]tex,
    basicstyle=\ttfamily,
    commentstyle=\color{violet},
    columns=fullflexible,
    keepspaces=true,
    upquote=true,
    showstringspaces=false,
    morestring=[s]\\\%,
    stringstyle=\color{red},
}
\begin{document}
\begin{lstlisting}
Foo % Comment 1
Bar % Comment 2
Baz \%abc\% Not a comment %still a comment
\end{lstlisting}
\end{document}

enter image description here

Improve this answer
1
  • According to the doc of option morecomment=[s]{<delim>}{<delim>}, morestring=[s]\\\% defines a string delimited by \\ and \%. Hence for input text \large % text, the characters \large % is recognized as a string. I tried options moretexcs={large} and texcsstyle=*<style>, it seems that the string tokenizer has higher precedence than texcs.
    – muzimuzhi Z
    Jun 7, 2020 at 22:34
0

(This only shows some failed attempts, hence is not a standard answer.)

As I commented under @UlfikeFischer's answer, morestring=[s]\\\% creates a string pattern which begins at \\ and ends with \%. Therefore for input text \large % text, \large % is recognized as a string and colored red. And this cannot be overwritten by morekeywords and keywordstyle.

I also tried listings aspect texcs and keyword, none of them succeeds.

  • When comment=[l]\% is set (this is the default setting), control characters such as \# and \; can both be set and highlighted as texcs or keywords, but this fails on \%.
  • When another character other than % is used as comment char, then \% can be set and highlighted as texcs or keyword.
\documentclass{article}
\usepackage{listings}
\usepackage{xcolor}

% a texcs attempt
\lstset{
  language=[latex]tex,
  basicstyle=\ttfamily,
  texcsstyle=*\color{orange}, % the star (*) means highlight the backslash
  commentstyle=\color{violet},
  columns=fullflexible,
  keepspaces=true,
  upquote=true,
  showstringspaces=false,
  comment=[l], % clear comment setting
  alsoletter={\#\;\%},
  moretexcs={cmd, Foo, AtBeginDocument, \#, \;, \%}
}

\begin{document}
Use \verb|C| as comment character
\begin{lstlisting}[comment={[l]C}]
\cmd \Foo % Comment 1
\#\; Bar % Comment 2
Baz \% Not a Comment
\AtBeginDocument
\end{lstlisting}

Use \verb|\%| as comment character
\begin{lstlisting}[comment={[l]\%}]
\cmd \Foo % Comment 1
\#\; Bar % Comment 2
Baz \% Not a Comment
\AtBeginDocument
\end{lstlisting}
\end{document}

enter image description here

I think it is the precedence that matters. It looks like there is a precedence order like "string ~ comment > keyword ~ texcs".

Improve this answer
0

Just use literate to replace the \% with %, as follows:

\documentclass{article}
\usepackage{listings}
\usepackage{xcolor}
\lstset{
    language=[latex]tex,
    basicstyle=\ttfamily,
    commentstyle=\color{violet},
    columns=fullflexible,
    keepspaces=true,
    upquote=true,
    showstringspaces=false,
    literate={\\\%}{\%}1, % Replace \% with %
}
\begin{document}
\begin{lstlisting}
Foo % Comment 1
Bar % Comment 2
Baz \% Not a comment
\end{lstlisting}
\end{document}

enter image description here

Answer from Do not comment parts of a listing, listings package

Improve this answer

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.