[Tex/LaTex] Highlight a prompt with the listings package

highlightinglistings

I use the listings package to typeset a series of commands in the language Octave (a free clone of Matlab) in my lecture notes. Most of the command lines look like this:

octave:1> A=eye(4)
A =

Diagonal Matrix

   1   0   0   0
   0   1   0   0
   0   0   1   0
   0   0   0   1

octave:2> det(A)
ans =  1
octave:3>

As you can see, each command is prefixed by a prompt in the form octave:N>, where N is the number of the command in the session (may have more than one character). I do not skip this prompt because I want my notes to look exactly like the students' screens. Output lines have no prefix.

I would like this command prefix to be formatted in a different color (grayed out, to mean that it is not as important as what follows).

How can I do that with listings? In the manual I find only an option gobble to ignore the first k characters of every line, but this does not work in my case since only some lines have this prefix.

Best Answer

Is this what you want?

Code

\documentclass{article}
\usepackage{listings,xcolor}
\lstset{
    language=Octave,
    moredelim=[s][\color{gray}]{octave:}{>}
}
\begin{document}
\begin{lstlisting}
octave:1> A=eye(4)
A =

Diagonal Matrix

   1   0   0   0
   0   1   0   0
   0   0   1   0
   0   0   0   1

octave:2> det(A)
ans =  1
octave:3>
\end{lstlisting}
\end{document}

Output

Output of posted code

`moredelim`

The moredelim key defines new delimiters that are used to format text manually between them. In this case the delimiters are octave: and > and they are not thrown away (that would happen if you use [is] instead of [s]).
Confer to manual section 3.3 and 4.5 to read more about the use of delimiters.

Related Solutions

[Tex/LaTex] Listings package: How to highlight math operators

You can't do this with the emph key. But you can do it using the literate key:

\documentclass{article}
\usepackage{listings,xcolor}
\begin{document}

\lstset{
emph={proc,retp,endp,local}, emphstyle={\color{blue}\textbf},
literate={./}{{{\color{red}./}}}2 {.^}{{{\color{red}.\^{}}}}2 {=}{{{\color{red}=}}}1
}

\begin{lstlisting}
proc(1) = tdist(n,v);
local x, z, z2, u, t;
x=rndn(n,1); 
z=rndn(n,v);
z2=z.^2; 
t=x./((U./v)^(1/2));
retp(t);
endp;
\end{lstlisting}

\end{document}

Note that all the braces are required, since you need to limit the scope of the \color command.

output of code

[Tex/LaTex] Listing language for “screen session”

This might answer some of your questions. For the prompt, you may use the literate option. Two ways are shown to color output. The first way is not very good but it gets the job done for very short and simple output. The other way is to define an output environment. The result from the two are different : when using the escape character, you are leaving the listings mode and the spacing between the letters is not the same. See the output text in red below.

\documentclass{minimal}

\usepackage{listings}
\usepackage{xcolor}

\lstnewenvironment{code}
    {\lstset{%
        basicstyle=\ttfamily,
        escapechar=~,
        morekeywords={foo,bar},
        keywordstyle=\color{green},
        literate={\$}{{\textcolor{blue}{\$}}}1}
    }
    {}

\lstnewenvironment{codeoutput}
    {\lstset{basicstyle=\ttfamily\color{red}}}
    {}

\begin{document}

\begin{code}
$ git status
# on branch "master"
foo in bar is blah

for short output
~\color{red}This is output\color{black}~
\end{code}

\begin{codeoutput}
This is output
\end{codeoutput}

\end{document}

The output is

output