Necessary package for "codeexample"

Question

What is the necessary package for

 \begin{codeexample}[]

 \end{codeexample}

In latex?

When we use this?

Answer 1

Presumably you have seen this command somewhere? However searching my local tree (or you could have used google)

$ grep -l codeexample /usr/local/texlive/2014/texmf-dist/tex/latex/*/*.sty
/usr/local/texlive/2014/texmf-dist/tex/latex/frankenstein/abbrevs.sty
/usr/local/texlive/2014/texmf-dist/tex/latex/frankenstein/attrib.sty
/usr/local/texlive/2014/texmf-dist/tex/latex/frankenstein/compsci.sty
/usr/local/texlive/2014/texmf-dist/tex/latex/frankenstein/lips.sty
/usr/local/texlive/2014/texmf-dist/tex/latex/frankenstein/moredefs.sty
/usr/local/texlive/2014/texmf-dist/tex/latex/frankenstein/newclude.sty
/usr/local/texlive/2014/texmf-dist/tex/latex/frankenstein/titles.sty
/usr/local/texlive/2014/texmf-dist/tex/latex/pgfplots/bugtracker.sty
/usr/local/texlive/2014/texmf-dist/tex/latex/tkz-doc/tkzexample.sty

so the frankenstein and tkzexample packages both define an environment of that name.

Answer 2

Note that the package tkzexample.sty does not actually define codeexample. It only refers to `codeexample' in this comment:

 % The author of the original code 
 % of the environment 'codeexample' is Till Tantau

However, tkzexample includes the environment:

 \begin{tkzltxexample}

which appears to be similar.

Here is a simple example:

\documentclass[10pt]{article}
\usepackage{xcolor}
\usepackage{pgf,tikz}
\usepackage{tkzexample} 


\colorlet{codeonlybackground}{red!10}% sets background for tkzltxexample

\begin{document}

This file started:

\begin{tkzltxexample}[]
\documentclass[10pt]{article}
\usepackage{xcolor}
\usepackage{pgf,tikz}
\usepackage{tkzexample} 
\colorlet{codeonlybackground}{red!10}% sets background for tkzltxexample
\begin{document}
...
\end{tkzltxexample}

\end{document}

which gives:

Note that the background color here is set via:

 \colorlet{codeonlybackground}{red!10}

The option very small is also useful.

\begin{tkzltxexample}[very small]

See also the answer of @alain-matthes for further information on displaying code and output in parallel.