[Tex/LaTex] Keyword Highlighting not working in Python with listings

listingssyntax highlighting

I am unable to get keywords to be highlighted in typeset Python.

Latex source:

\documentclass{minimal}
\usepackage{listings}
\usepackage{xcolor}

\lstset{
language=Python,
frame=single,
numbers=left,
showspaces=false,
showstringspaces=false,
basicstyle=\ttfamily,
captionpos=t,
caption=\lstname
keywordstyle=\ttfamily \color{blue},
keywordstyle=[2]\ttfamily \color{blue},
stringstyle=\color{green}\ttfamily,
commentstyle=\color{red}\ttfamily
}

\begin{document}

Keywords are not highlighted properly in the below segment:

\begin{lstlisting}
# This is a comment
print("Latex keywordstyles not working?")
if this_is_highlighted:
    print("Yay, this works!")
else:
    print("Why isn't this working?")
\end{lstlisting}
\end{document}

Typeset output:

Why isn't the keywordstyle coloring working when the keywords are properly defined in lstlang1.sty?

Best Answer

Try this:

% My standard header for TeX.SX answers:
\documentclass[a4paper]{article} % To avoid confusion, let us explicitly 
                                 % declare the paper format.

\usepackage[T1]{fontenc}         % Not always necessary, but recommended.
% End of standard header.  What follows pertains to the problem at hand.

\usepackage{xcolor}
\usepackage{listings}

\lstdefinestyle{Python}{
    language        = Python,
    basicstyle      = \ttfamily,
    keywordstyle    = \color{blue},
    keywordstyle    = [2] \color{teal}, % just to check that it works
    stringstyle     = \color{green},
    commentstyle    = \color{red}\ttfamily
}



\begin{document}

% This must be placed after "\begin{document}":
\lstset{
    frame       = single,
    numbers     = left,
    showspaces  = false,
    showstringspaces    = false,
    captionpos  = t,
    caption     = \lstname
}

Now keywords \emph{are} properly highlighted in the following code snippet:

\begin{lstlisting}[style = Python]
# This is a comment
print("Latex keywordstyles not working?")
if this_is_highlighted:
    print("Yay, this works!")
else:
    print("Why isn't this working?")
\end{lstlisting}

\end{document}

Output:

Related Solutions

[Tex/LaTex] Python “as” keyword ignored in Listings

The morekeyword=as option works if you declare it after telling listings that the language to be used is Python:

\documentclass{article}
\usepackage{listings}

\begin{document}
\begin{lstlisting}[language=Python,morekeywords=as]
#!/usr/bin/env python
"""
An animated image
"""
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.animation as animation
\end{lstlisting}
\end{document}

enter image description here

It's perhaps better to define an own environment for Python:

\lstnewenvironment{Python}[1][]
  {\lstset{language=Python,
           morekeywords=as,
           #1}%
  }
  {}

so that it will be possible to write

\begin{Python}
<Python code>
\end{Python}

possibly giving other local options, say

\begin{Python}[basicfamily=\ttfamily]
<Python code>
\end{Python}

Syntax highlighting of numeric literals with the listings package

Try this code. Its a very simplified solution. See the links mentioned in the comments and also Changing the color of numbers and special words for more comprehensive solutions.

\documentclass{article}

\usepackage{listings}
\usepackage{xcolor} 

\renewcommand{\lstlistingname}{Phyton code}

\lstdefinestyle{mystyle}{
    language=Python,            
    captionpos=b,             
}   

\lstset{style=mystyle}

\newcommand\digitstyle{\textcolor{orange}}
    {0}{{{\digitstyle0}}}1
    {1}{{{\digitstyle1}}}1
    {2}{{{\digitstyle2}}}1
    {3}{{{\digitstyle3}}}1
    {4}{{{\digitstyle4}}}1
    {5}{{{\digitstyle5}}}1
    {6}{{{\digitstyle6}}}1
    {7}{{{\digitstyle7}}}1
    {8}{{{\digitstyle8}}}1
    {9}{{{\digitstyle9}}}1
    {.}{{{\digitstyle.}}}1
}


\begin{document}
    
    \begin{lstlisting}[language=Python, caption=Highlighting  numeric literals.]    
        var_a = 3
        var_b = 20000
        var_c = 1.75e12
        var_d = 0.1415      
    \end{lstlisting}    

\end{document}

Best Answer

Related Solutions

[Tex/LaTex] Python “as” keyword ignored in Listings

Syntax highlighting of numeric literals with the listings package

Related Question