[Tex/LaTex] Problem with literate and breaklines=true in listings package

listings

As the title says, the option breaklines=true seems to have an undesired interaction when using literate; in the following example the closing parenthesis doesn't get colorized 

\documentclass{article}
\usepackage{xcolor}
\usepackage{listings}

\lstset{
  literate=
    {)}{{\textcolor{red}{)}}}{1}
    {(}{{\textcolor{red}{(}}}{1},
  breaklines=true,
}

\begin{document}

\begin{lstlisting}
()
\end{lstlisting}

\end{document}

enter image description here

Commenting out the breaklines=true option produces the desired result. What is producing this odd behaviour and how can it be prevented?

Best Answer

When the breaklines=true option is given, a code that's executed after doing \lst@literate (which assigns the special meaning to the defined characters) is

\lst@ifbreaklines \lst@Def {`)}{\lst@breakProcessOther )}\fi

and this expands to

\lccode `\~=#1\lowercase {\def ~}{\lst@breakProcessOther )}

which makes the active ) expand to

\lst@breakProcessOther )

where ) is not active. All this happens when \lsthk@SelectCharTable is executed.

If, just for trying, I apply a patch with etoolbox

\makeatletter
\patchcmd{\lsthk@SelectCharTable}{`)}{`]}{}{}
\makeatother

then the right parenthesis will be printed red, but a similar problem will appear with the ] in case, say,

literate=
  {[}{{\textcolor{red}{[}}}{1}
  {]}{{\textcolor{red}{]}}}{1},

is specified (the right bracket will become a black right parenthesis, which I expected).

I believe this has to do with precautions listings makes in order to correctly treat parenthesized expressions. And I suspect that not much can be done about this.

If I try to patch the definition of \lsthk@SelectCharTable removing that conditional part, then the right parenthesis comes out red. But I don't know if other problems will arise.

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