\documentclass{article} \usepackage{libertinus-otf} \setmonofont[Scale=MatchLowercase,FakeStretch=0.9]{AnonymousPro-Regular.ttf} \newif\ifChangeBar \ChangeBarfalse \usepackage{fancyvrb} \usepackage{fancyvrb-ex} \usepackage{xurl} \usepackage[colorlinks,linktocpage]{hyperref} \parskip=3pt plus 1pt minus 1pt % \newcommand\FBoxPackage{`\textsf{fancybox}'} \newcommand\FVrbPackage{`\textsf{fancyvrb}'} \newcommand\cs[1]{\texttt{\textbackslash#1}} % % From ltugboat.cls % % Typeset the name of an environment \providecommand\env[1]{\textsf{#1}} \providecommand\clsname[1]{\textsf{#1}} \providecommand\pkgname[1]{\textsf{#1}} \providecommand\optname[1]{\textsf{#1}} \providecommand\progname[1]{\textsf{#1}} % % A list of options for a package/class \newenvironment{optlist}{\begin{description}% \renewcommand\makelabel[1]{% \descriptionlabel{\mdseries\optname{##1}}}% \itemsep0.25\itemsep}% {\end{description}} % % Utility macros % % Special dashes \makeatletter \def\thinskip{\hskip 0.16667em\relax} \def\endash{--} \def\emdash{\endash-} \def\d@sh#1#2{\unskip#1\thinskip#2\thinskip\ignorespaces} \def\dash{\d@sh\nobreak\endash} \def\Dash{\d@sh\nobreak\emdash} \makeatother \newif\ifPostScriptFonts \PostScriptFontstrue % \setlength{\columnseprule}{0.6pt} % \newif\ifmulticols %\IfFileExists{multicol.sty}{\multicolstrue}{} \newif\ifpstricks \pstrickstrue % \title{The `\textsf{fancyvrb}' package\\Fancy Verbatims in \LaTeX} \author{Timothy Van Zandt\\Princeton University\\Princeton -- USA\\[5mm] % {\footnotesize \url{tvz@Princeton.EDU}}\\[5mm] {Packaging and documentation by}\\ {\footnotesize Denis Girou (CNRS/IDRIS -- France),}\\[-2mm] {\footnotesize Sebastian Rahtz (Elsevier -- GB)}\\[-2mm] {\footnotesize and}\\[-2mm] {\footnotesize Herbert Voß\ (FU Berlin -- DE)} } \date{Version 3.7\\ \today} \fvset{frame=single,xrightmargin=0cm,numbers=left,numbersep=3pt,commentchar=Z} \begin{document} \maketitle % \begin{abstract} This package provides very sophisticated facilities for reading and writing verbatim \TeX{} code. Users can perform common tasks like changing font family and size, numbering lines, framing code examples, colouring text and conditionally processing text. \end{abstract} \begin{center} Report bugs to \url{hvoss@tug.org} \end{center} \vfill Thanks to Claudio Beccari, Jean-François Burnol, Philippe Esperet, %\url{esperet@marie.polytechnique.fr}, Michael Friendly, %\url{friendly@hotspur.psych.yorku.ca}, Mario Hassler, %\url{HASSLER@ippnv2.ipp.kfa-juelich.de}, Mikhail Kolodin, %\url{myke@morrigan.spb.su}, Andreas Matthias, Frank Mittelbach, Rolf Niepraschk, %\url{Rolf.Niepraschk@gmx.de}, Will Robertson, Ulrich M. Schwarz, Thomas Siegel, % \url{siegel@aix520.informatik.uni-leipzig.de}, Clemens Steinke, and Vladimir Volovich. %\url{vvv@vvv.vsu.ru}. \clearpage \tableofcontents \clearpage %\part{\texttt{fancyvrb} package by Timothy Van Zandt} \part{Package \texttt{fancyvrb}} \section{Introduction} % \FVrbPackage{} is the development of the \emph{verbatim} macros of the \FBoxPackage{} package, Section 11 of \cite{FancyBox}. It offers six kinds of extended functionality, compared to the standard \LaTeX{} \textsf{verbatim} environment: \begin{enumerate} \item verbatim commands can be used in footnotes, \item several verbatim commands are enhanced, \item a variety of verbatim environments are provided, with many parameters to change the way the contents are printed; it is also possible to define new customized verbatim environments, \item a way is provided to save and restore verbatim text and environments, \item there are macros to write and read files in verbatim mode, with the usual versatility, \item you can build \emph{example} environments (showing both result and verbatim text), with the same versatility as normal verbatim. \end{enumerate} The package works by scanning a line at a time from an environment or a file. This allows it to pre-process each line, rejecting it, removing spaces, numbering it, etc, before going on to execute the body of the line with the appropriate catcodes set. \section{Verbatim material in footnotes} After a \cs{VerbatimFootnotes} macro declaration (to use after the preamble), it is possible to put verbatim commands and environments (the \LaTeX{} or \FVrbPackage{} ones) in footnotes, unlike in standard \LaTeX: \begin{Example} \VerbatimFootnotes We can put verbatim\footnote{\verb+_Yes!_+} text in footnotes. \end{Example} \section{Improved verbatim commands} % The \cs{DefineShortVerb} macro allows us to define a special character as an abbreviation to enclose verbatim text and the \cs{UndefineShortVerb} macro suppresses the special meaning of the specified character (the same functionalities are provided in the \LaTeX{} `\textsf{shortvrb}' package): \fvset{xrightmargin=4.8cm} \begin{SideBySideExample} \DefineShortVerb{\|} We can simply write \Verb+_verbatim_+ material using a single |_delimiter_| \UndefineShortVerb{\|} \DefineShortVerb{\+} And we can +_change_+ the character. \end{SideBySideExample} To make matters more versatile, we can nominate \emph{escape} characters in verbatim text (using the \cs{Verb} macro or with a `shortverb' character defined), to perform formatting or similar tasks, using the \texttt{commandchars} parameter as shown for environments in paragraph \ref{sec:commandchars}. \section{Verbatim environments} Several verbatim environments are available, each with a lot of parameters to customize them. In the following examples we use the \texttt{Verbatim} environment, which is the equivalent of the standard \texttt{verbatim}. The parameters can be set globally using the \cs{fvset} macro or in an optional argument after the start of the environment\footnote{For clarification in this paper, note that we generally indent each verbatim line with two spaces.}$^,$\footnote{This mechanism uses the `\textbf{keyval}' package from the standard \LaTeX{} graphics distribution, written by David \textsc{Carlisle}.}. \begin{SideBySideExample} \begin{Verbatim} First verbatim line. Second verbatim line. \end{Verbatim} \end{SideBySideExample} \subsection{Customization of verbatim environments} The appearance of verbatim environments can be changed in many and varied ways; here we list the keys that can be set. \subsubsection{Comments} \begin{optlist} \item[commentchar (character)]: character to define comments in the verbatim code, so that lines starting with this character will not be printed (\emph{Default: empty}). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[commentchar=!] A comment Verbatim line. ! A comment that you will not see \end{Verbatim} \end{SideBySideExample} Take care to a special effect if the comment character is not the first non blank one: it is because this character is in fact managed as the \TeX{} comment one, that is to say that it gobble the newline character too. So, in this case, the current line will be joined with the next one and, more, the last one will be lost if it contain a comment, as \FVrbPackage{} print a line only after finding it end character, which will never occured in this case... \begin{SideBySideExample} \begin{Verbatim}[commentchar=\%] First line. % First line Second. Third line. % Third line lost... \end{Verbatim} \end{SideBySideExample} \subsubsection{Initial characters to suppress} \begin{optlist} \item[gobble (integer)]: number of characters to suppress at the beginning of each line (up to a maximum of 9), mainly useful when environments are indented (\emph{Default: empty} \Dash no character suppressed). \end{optlist} \begin{SideBySideExample} \begin{Verbatim} Verbatim line. \end{Verbatim} \begin{Verbatim}[gobble=2] Verbatim line. \end{Verbatim} \begin{Verbatim}[gobble=8] Verbatim line. \end{Verbatim} \end{SideBySideExample} \subsubsection{Customization of formatting} \begin{optlist} \item[formatcom (command)]: command to execute before printing verbatim text (\emph{Default: empty}). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[formatcom=\color{red}] First verbatim line. Second verbatim line. \end{Verbatim} \end{SideBySideExample} \subsubsection{Changing individual line formatting} The macro \cs{FancyVerbFormatLine} defines the way each line is formatted. Its default value is \verb+\def\FancyVerbFormatLine#1{#1}+, but we can redefine it at our convenience (\texttt{FancyVerbLine} is the name of the line counter): {\fvset{fontsize=\small} \begin{SideBySideExample} Z\fvset{fontsize=\normalsize} \renewcommand{\FancyVerbFormatLine}[1]{% \makebox[0cm][l]{$\Rightarrow$}#1} \begin{Verbatim} First verbatim line. Second verbatim line. Third verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{SideBySideExample} \renewcommand{\FancyVerbFormatLine}[1]{% \ifodd\value{FancyVerbLine}% \MakeUppercase{#1}\else#1\fi} \begin{Verbatim} First verbatim line. Second verbatim line. Third verbatim line. \end{Verbatim} \end{SideBySideExample} } \subsubsection{Fonts} \begin{optlist} \item[fontfamily (family name)]: font family to use. \texttt{tt}, \texttt{courier} and \texttt{helvetica} are pre-defined (\emph{Default:~tt}). \end{optlist} \ifPostScriptFonts We can guess that PostScript fonts are available \begin{SideBySideExample} \begin{Verbatim}[fontfamily=helvetica] Verbatim line. \end{Verbatim} \end{SideBySideExample} \else \begin{quote} \textbf{\large Warning!} PostScript fonts seems not available on your platform (we are looking for the file \texttt{times.sty}, so we will not show the examplaes using such PostScript fonts. \end{quote} \fi \begin{optlist} \item[fontsize (font size)]: size of the font to use (\emph{Default: auto} \Dash the same as the current font). If you use the `\textsf{relsize}' package too, you can require a change of the size proportional to the current one (for instance: \verb+fontsize=\relsize{-2}+). \end{optlist} \ifPostScriptFonts We can guess that PostScript fonts are available \begin{SideBySideExample} \begin{Verbatim}[fontsize=\small] Verbatim line. \end{Verbatim} \begin{Verbatim}[fontfamily=courier, fontsize=\large] Verbatim line. \end{Verbatim} \end{SideBySideExample} \else \begin{SideBySideExample} \begin{Verbatim}[fontsize=\small] Verbatim line. \end{Verbatim} \end{SideBySideExample} \fi \begin{optlist} \item[fontshape (font shape)]: font shape to use (\emph{Default: auto} \Dash the same as the current font). \end{optlist} \ifPostScriptFonts We can guess that PostScript fonts are available \begin{SideBySideExample} \begin{Verbatim}[fontfamily=courier, fontshape=it] Verbatim line. \end{Verbatim} \end{SideBySideExample} \else \begin{SideBySideExample} \begin{Verbatim}[fontshape=it] Verbatim line. \end{Verbatim} \end{SideBySideExample} \fi \begin{optlist} \item[fontseries (series name)]: \LaTeX{} font `series' to use (\emph{Default: auto} \Dash the same as the current font). \end{optlist} \ifPostScriptFonts We can guess that PostScript fonts are available \begin{SideBySideExample} \begin{Verbatim}[fontfamily=courier, fontseries=b] Verbatim line. \end{Verbatim} \end{SideBySideExample} \else \begin{SideBySideExample} \begin{Verbatim}[fontseries=b] Verbatim line. \end{Verbatim} \end{SideBySideExample} \fi \subsubsection{Types and characteristics of frames} \begin{optlist} \item[frame (none$\mid$leftline$\mid$topline$\mid$bottomline$\mid$lines$\mid$single)]: type of frame around the verbatim environment (\emph{Default: none} \Dash no frame). With \textsf{leftline} and \textsf{single} modes, a space of a length given by the \LaTeX{} \cs{fboxsep} macro is added between the left vertical line and the text. \end{optlist} Problem at the top of a page... \begin{SideBySideExample} \begin{Verbatim}[frame=leftline] Verbatim line. \end{Verbatim} \begin{Verbatim}[frame=topline] Verbatim line. \end{Verbatim} \begin{Verbatim}[frame=bottomline] Verbatim line. \end{Verbatim} \begin{Verbatim}[frame=lines] Verbatim line. \end{Verbatim} \begin{Verbatim}[frame=single] Verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[framerule (dimension)]: width of the rule of the frame (\emph{Default: 0.4pt if framing specified}). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[frame=single, framerule=1mm] Verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[framesep (dimension)]: width of the gap between the frame and the text (\emph{Default: \cs{fboxsep}}). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[frame=single, framesep=5mm] Verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[rulecolor (color command)]: color of the frame rule, expressed in the standard \LaTeX{} way (\emph{Default: black}). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[frame=single, rulecolor=\color{red}] Verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[fillcolor (color command)]: color used to fill the space between the frame and the text (its thickness is given by \texttt{framesep}) (\emph{Default: none} \Dash no color). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[frame=single, framerule=1mm,framesep=3mm, rulecolor=\color{red}, fillcolor=\color{yellow}] Verbatim line. \end{Verbatim} \end{SideBySideExample} \subsubsection{Label for the environment} \begingroup \newcommand\Vitem{\SaveVerb[aftersave={\item[\UseVerb{Vitem}]}]{Vitem}} \DefineShortVerb{\|} \begin{optlist} \Vitem|label ({[string]string})|: label(s) to print on top, bottom or both frame lines of the environment to describe it content (\emph{Default: empty} \Dash no label). If the label(s) contains special characters, as a comma or an equal sign, it must be put inside a group. If only one string is given, it will be used for both top and bottom lines (if the two are printed), but if an optional first label is given too, this one will be used for the top line and the second one for the bottom line. Note also that, if another value than \textsf{topline}, \textsf{bottomline}, \textsf{lines} or \textsf{single} is used for the \textsf{frame} parameter, the label(s) will not be printed. \end{optlist} \endgroup Problem at the top of a page... \begin{SideBySideExample} \fvset{gobble=2} \begin{Verbatim}[frame=single, label=My text] First verbatim line. Second verbatim line. \end{Verbatim} \begin{Verbatim}[frame=topline, framesep=4mm, label=\fbox{\Large\emph{The code}}] First verbatim line. Second verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[labelposition (none$\mid$topline$\mid$bottomline$\mid$all)]: position where to print the label if one is defined, which must be coherent with the kind of frame chosen (\emph{Default: none if the label is empty, topline if one label is defined and all if two are defined}). Of course, some incompatible options (like \textsf{frame=topline,labelposition=bottomline}) will not print the label. \end{optlist} Problem at the top of a page... \begin{SideBySideExample} \fvset{gobble=2} \begin{Verbatim}[frame=single, framesep=2mm, label=Text,labelposition=all] First verbatim line. Second verbatim line. \end{Verbatim} \begin{Verbatim}[frame=lines, label=Text,labelposition=topline] First verbatim line. Second verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{SideBySideExample} \begin{Verbatim}[frame=bottomline, framesep=3mm, label=\textit{Code included}, labelposition=bottomline] First verbatim line. Second verbatim line. \end{Verbatim} \begin{Verbatim}[frame=lines, framesep=3mm, label={[Beginning of code]End of code}] First verbatim line. Second verbatim line. \end{Verbatim} \end{SideBySideExample} \subsubsection{Line numbering} \begin{optlist} \item[numbers (none$\mid$left$\mid$right)]: numbering of the verbatim lines (\emph{Default: none} \Dash no numbering). If requested, this numbering is done \emph{outside} the verbatim environment. \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[gobble=2,numbers=left] First verbatim line. Second verbatim line. \end{Verbatim} \begin{Verbatim}[gobble=2, numbers=right,numbersep=0pt] First verbatim line. Second verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[numbersep (dimension)]: gap between numbers and verbatim lines (\emph{Default: 12pt}). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[gobble=2, numbers=left,numbersep=2pt] First verbatim line. Second verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[firstnumber (auto$\mid$last$\mid$integer)]: number of the first line (\emph{Default: auto} \Dash numbering starts from 1). \textsf{last} means that the numbering is continued from the previous verbatim environment. If an integer is given, its value will be used to start the numbering. \end{optlist} \begin{SideBySideExample} \fvset{gobble=2, numbers=left,numbersep=3pt} \begin{Verbatim} Verbatim line. \end{Verbatim} \begin{Verbatim}[firstnumber=last] Verbatim line. \end{Verbatim} \begin{Verbatim}[firstnumber=100] Verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[stepnumber (integer)]: interval at which line numbers are printed (\emph{Default:~1} \Dash all lines are numbered). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[gobble=2,numbers=left, numbersep=3pt,stepnumber=2] First verbatim line. Second verbatim line. Third verbatim line. \end{Verbatim} \end{SideBySideExample} The macro \cs{theFancyVerbLine} defines the typesetting style of the numbering, and the counter used is \texttt{FancyVerbLine}: \begin{SideBySideExample} \renewcommand{\theFancyVerbLine}{% \textcolor{red}{\small 8.\alph{FancyVerbLine}}} \begin{Verbatim}[gobble=2, numbers=left,numbersep=2pt] First verbatim line. Second verbatim line. Third verbatim line. \end{Verbatim} \end{SideBySideExample} \ifChangeBar\begin{changebar}\fi \begin{optlist} \item[numberblanklines (boolean)]: to number or not the empty lines (really empty or containing blank characters only) (\emph{Default: true} \Dash all lines are numbered). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[gobble=2,numbers=left, numbersep=3pt, numberblanklines=false] First verbatim line. Second verbatim line. \end{Verbatim} \end{SideBySideExample} \ifChangeBar\end{changebar}\fi % \subsubsection{Selection of lines to print} \begin{optlist} \item[firstline (integer)]: first line to print (\emph{Default: empty} \Dash all lines from the first are printed). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[gobble=2,firstline=2, numbers=left,numbersep=2pt] First verbatim line. Second verbatim line. Third verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[lastline (integer)]: last line to print (\emph{Default: empty} \Dash all lines until the last one are printed). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[gobble=2,lastline=1, numbers=left,numbersep=2pt] First verbatim line. Second verbatim line. Third verbatim line. \end{Verbatim} \end{SideBySideExample} Instead of specifying a firstline at which to start printing a range of lines, you can define a start string; the start of the range is the first line that exactly equals the string. (The comparison is made before any characters are gobbled off the front of the line.) Similarly for a stop string. You can mix line-numbers and strings, e.g.\ start at firstline, and end at a stop string. Specifying the strings is a bit klunky. Initially you must define the strings with \cs{newcommand*} as in: \begin{SideBySideExample}[gobble=2] \newcommand*\FancyVerbStartString{FROM} \newcommand*\FancyVerbStopString{TO} \begin{Verbatim} First verbatim line. FROM Second verbatim line. TO Third verbatim line. \end{Verbatim} \end{SideBySideExample} \noindent To redefine the strings, you must use \cs{renewcommand*}. \subsubsection{Spaces and tab characters} \begin{optlist} \item[showspaces (boolean)]: print a special character representing each space (\emph{Default: false} \Dash spaces not shown). \end{optlist} \begin{SideBySideExample}[gobble=0] \begin{Verbatim}[showspaces=true] Verbatim line. \end{Verbatim} \end{SideBySideExample} In practice, all verbatim environments have a~\texttt{*} variant, which sets \texttt{showspaces=true}: \begin{SideBySideExample}[gobble=0] \begin{Verbatim*} Verbatim line. \end{Verbatim*} \end{SideBySideExample} There are also some parameters to determine the way tab characters are interpreted (using tabs is in fact a rather old-fashioned style of coding): \begin{optlist} \item[showtabs (boolean)]: explicitly show tab characters (\emph{Default: false} \Dash tab characters not shown). \end{optlist} \begin{optlist} \item[obeytabs (boolean)]: position characters according to the tabs (\emph{Default: false} \Dash tab characters are added to the current position). \end{optlist} \begin{optlist} \item[tabsize (integer)]: number of spaces given by a tab character (\emph{Default:~8}). \end{optlist} \subsubsection{Space between lines} \begin{optlist} \item[baselinestretch (auto$\mid$dimension)]: value to give to the usual `baselinestretch' \LaTeX{} parameter (\emph{Default: auto} \Dash its current value just before the verbatim command). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[baselinestretch=2] First verbatim line. Second verbatim line. \end{Verbatim} \end{SideBySideExample} \subsubsection{Escape characters for inserting commands} \begin{optlist} \item[commandchars (three characters)]: characters which define the character which starts a macro and marks the beginning and end of a group; thus lets us introduce \emph{escape} sequences in verbatim code. Of course, it is better to choose special characters which are not used in the verbatim text! (\emph{Default: empty}). \label{sec:commandchars} \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[commandchars=\\\{\}] \textit{This is a comment} First verbatim line. \fbox{Second} verbatim line. \textcolor{red}{Third} verbatim line. \end{Verbatim} \begin{Verbatim}[commandchars=+\[\]] +textit[\textbf{Verbatim} line]. \end{Verbatim} \end{SideBySideExample} \ifChangeBar\begin{changebar}\fi Using this way, it is also possible to put labels to be able, later, to make reference to some lines of the verbatim environments: \begin{SideBySideExample} \begin{Verbatim}[commandchars=\\\{\}, numbers=left,numbersep=2pt] First verbatim line. Second line.\label{vrb:Important} Third verbatim line. \end{Verbatim} As I previously shown line~\ref{vrb:Important}, it is... \end{SideBySideExample} \ifChangeBar\end{changebar}\fi \subsubsection{Margins} \begin{optlist} \item[xleftmargin (dimension)]: indentation to add at the start of each line (\emph{Default:~0pt} \Dash no left margin). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[frame=single, xleftmargin=5mm] Verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[xrightmargin (dimension)]: right margin to add after each line (\emph{Default:~0pt} \Dash no right margin). \end{optlist} \begin{SideBySideExample} \begin{Verbatim}[frame=single, xrightmargin=1cm] Verbatim line. \end{Verbatim} \end{SideBySideExample} \begin{optlist} \item[resetmargins (boolean)]: reset the left margin, which is useful if we are inside other indented environments (\emph{Default: false} \Dash no reset of the margin). \end{optlist} {% \DefineVerbatimEnvironment{Verbatim}{Verbatim}{gobble=0,numbers=none} \begin{SideBySideExample} \begin{itemize} \item First item \begin{Verbatim}[frame=single] Verbatim line. \end{Verbatim} \item Second item \begin{Verbatim}[frame=single, resetmargins=true] Verbatim line. \end{Verbatim} \end{itemize} \end{SideBySideExample} } \subsubsection{Overfull box messages} \begin{optlist} \item[hfuzz (dimension)]: value to give to the \TeX{} \cs{hfuzz} dimension for text to format. This can be used to avoid seeing some unimportant \emph{Overfull box} messages (\emph{Default:~2pt}). \end{optlist} \subsubsection{Page breaks} \begin{optlist} \item[samepage (boolean)]: in very special circumstances, we may want to make sure that a verbatim environment is not broken, even if it does not fit on the current page. To avoid a page break, we can set the \texttt{samepage} parameter to \emph{true} (\emph{Default: false}). \end{optlist} \subsubsection{Catcode characters} \begin{optlist} \item[codes (macro)]: to specify \emph{catcode} changes (\emph{Default: empty}). \end{optlist} For instance, this allows us to include formatted mathematics in verbatim text: {\fvset{fontsize=\small} \begin{SideBySideExample} Z\fvset{fontsize=\normalsize} \begin{Verbatim}[commandchars=\\\{\}, codes={\catcode`$=3\catcode`^=7}] x=1/sqrt(z**2) ! $\frac{1}{\sqrt{z^2}}$ \end{Verbatim} \end{SideBySideExample} } %$ \subsubsection{Active characters} \begin{optlist} \item[defineactive (macro)]: to define the effect of \emph{active} characters (\emph{Default: empty}). \end{optlist} This allows us to do some devious tricks: see the example in Section \ref{sec:VerbatimInclude} on page~\pageref{sec:VerbatimInclude}. \subsubsection{Reference label} \begin{optlist} \item[reflabel (