Creating independently-numbered Chapter-level structures

Question

I'm writing a book in which, between chapters, I may have chapter-size chunks of text that discuss a software package related to the book's content. Consequently, I wish to label these things something other than chapters. For example, I'd like my TOC to be something like this:

1   Here would go my title for Chapter 1

2   Here would go my title for Chapter 2

Software Break 1: Getting to Know Foo and Bar

3   Here would go my title for Chapter 3

Software Break 2: Here Come Baz and Quux!

4   Here would go my title for Chapter 4

and so on. You can see three requirements here:

1. Software Breaks have a counter independent from that of Chapters.
2. Software Breaks appear differently in the TOC.

3. Otherwise, Software Breaks function identically to chapters. E.g., somewhere in a chapter, I might type something like this:

   We covered widget frozzling in Software Break \ref{break:intro} on page \pageref{break:intro}.
   

I guess what I'm saying is that I want to recreate whatever the standard book document class does for Chapters, but again, as a totally other class of thing, called a Software Break. So I took a look at the book.cls source code (here), but I'm simply not a sophisticated enough LaTeXer to understand it yet. I could try copying and pasting big chunks of stuff about chapter definitions, but I'd have no confidence I was doing it right or that it would succeed.

Alternately, perhaps what I need to do is manually change the name/appearance/number of just some of my chapters? I won't exactly be moving chapters around a lot, so if I have to manually number them, it's not a big deal.

Any advice appreciated! Thank you!

Answer 1

Here's how I ended up solving my own problem.

Overall gist:

1. Create another counter for software break sections.
2. Create a new command for starting software break sections, which swaps the chapter counter for the software break counter, reformats chapter headings and numbering and appearance in the ToC and everything.
3. Create a separate command for when a software break is ending, to put everything back to normal.

The code looks like this, and requires \usepackage{titlesec}.

% Define and initialize counters used below
\newcounter{swbreak}
\setcounter{swbreak}{0}
\newcounter{swapspace}

% Choose the phrase that will be used in the titles:
\def\swbreakphrase{Software Break}

% The following one-parameter environment is used to wrap a "software break."
% Yes, that's write, you wrap the entire chapter-like thing in this:
% \begin{swbreak}
% ...lots and lots of stuff...
% \end{swbreak}
\newenvironment{swbreak}[1]{
    % Swap chapter and software break counters:
    \setcounter{swapspace}{\value{chapter}}
    \setcounter{chapter}{\value{swbreak}}
    % Use A,B,C for software breaks instead of 1,2,3:
    \renewcommand{\thechapter}{\Alph{chapter}}
    % Don't let the actual chapter title *also* show up in the ToC:
    \addtocontents{toc}{\protect\setcounter{tocdepth}{-1}}
    % Change Chapter heading to Software Break heading, and start a new "chapter":
    \titleformat{\chapter}[display]{\normalfont\huge\bfseries}{Software Break \thechapter}{20pt}{\Huge}
    \chapter{#1}
    % Re-enable chapter heading style, and chapters appearing in ToC:
    \addtocontents{toc}{\protect\setcounter{tocdepth}{1}}
    \titleformat{\chapter}[display]{\normalfont\huge\bfseries}{\chaptertitlename\ \thechapter}{20pt}{\Huge}
    % Insert a custom ToC entry style for this software break:
    \addcontentsline{toc}{chapter}{\swbreakphrase\ \Alph{chapter}: #1}
}{
    % Swap chapter and software break counters back to the way they were:
    \setcounter{swbreak}{\value{chapter}}
    \setcounter{chapter}{\value{swapspace}}
    % Use 1,2,3 again instead of A,B,C:
    \renewcommand{\thechapter}{\arabic{chapter}}
}

Answer 2

Here is an example that defines an environment for Software Breaks and corrects the TOC

\documentclass{book}
\makeatletter

\newcommand\SWbreakname{Software Break}

%-- Counter
\newcounter{SWbreak}
\renewcommand\theSWbreak{\Alph{SWbreak}}
\@addtoreset{equation}{SWbreak}
\@addtoreset{table}{SWbreak}
\@addtoreset{figure}{SWbreak}

%-- Software break environment
%-- Usage: \begin{SoftwareBreak}[<short title>]{<full title>}
%--           Contents....
%--        \end{SoftwareBreak}
%--
\newenvironment{SoftwareBreak}[2][\SB@temp]
   {\gdef\SB@temp{#2}%
    \global\let\@chapapp@old=\@chapapp
    \global\let\thechapter@old=\thechapter
    \gdef\@chapapp{\SWbreakname}
    \gdef\thechapter{\theSWbreak}%
    \SB@chapt{#1}{#2}%
   }%
   {%
    \global\let\@chapapp=\@chapapp@old
    \global\let\thechapter=\thechapter@old}

%-- Custom chapter to correct TOC
\newcommand\SB@chapt[2]{%
    \if@openright\cleardoublepage\else\clearpage\fi
    \thispagestyle{plain}%
    \global\@topnum\z@
    \@afterindentfalse
    \ifnum \c@secnumdepth >\m@ne
        \if@mainmatter
            \refstepcounter{SWbreak}%
            \addcontentsline{toc}{SWbreak}%
                {\protect\numberline{\SWbreakname~\theSWbreak:}#1}%
        \else
            \addcontentsline{toc}{SWbreak}{#1}%
        \fi
    \else
        \addcontentsline{toc}{SWbreak}{#1}%
    \fi
    \chaptermark{#1}%
    \addtocontents{lof}{\protect\addvspace{10\p@}}%
    \addtocontents{lot}{\protect\addvspace{10\p@}}%
    \if@twocolumn
        \@topnewpage[\@makechapterhead{#2}]%
    \else
        \@makechapterhead{#2}%
        \@afterheading
    \fi}

%-- TOC formating
\newcommand*\l@SWbreak[2]{%
  \ifnum \c@tocdepth >\m@ne
    \addpenalty{-\@highpenalty}%
    \vskip 1.0em \@plus\p@
    \settowidth\@tempdima{\bfseries \SWbreakname~XX:~}%
    \begingroup
      \parindent \z@ \rightskip \@pnumwidth
      \parfillskip -\@pnumwidth
      \leavevmode \bfseries
      \advance\leftskip\@tempdima
      \hskip -\leftskip
      #1\nobreak\hfil \nobreak\hb@xt@\@pnumwidth{\hss #2}\par
      \penalty\@highpenalty
    \endgroup
  \fi}

%-- Keep hyperref happy
\def\toclevel@SWbreak{0}

\makeatother

\usepackage{lipsum}
\begin{document}
\frontmatter
\tableofcontents
\listoffigures

\mainmatter
\chapter{First Chapter}
\section{A section}
\lipsum[1]
\section{Another section}
\lipsum[1]
\begin{figure}
    \caption{A figure}
\end{figure}
\lipsum[1]

\begin{SoftwareBreak}[First Software Break]
                     {First Software Break plus a very long line to check for wrapping}
    \section{A section in a Software Break}
    \lipsum[1]
    \section{Another section in a Software Break}
    \lipsum[1]
    \begin{figure}
        \caption{A figure}
    \end{figure}
    \lipsum[1]
\end{SoftwareBreak}

\chapter{Second Chapter}
\section{A section}
\lipsum[1]
\section{Another section}
\lipsum[1]
\begin{figure}
    \caption{A figure}
\end{figure}
\lipsum[1]

\begin{SoftwareBreak}{Second Software Break}
    \section{A section in a Software Break}
    \lipsum[1]
    \section{Another section in a Software Break}
    \lipsum[1]
    \begin{figure}
        \caption{A figure}
    \end{figure}
    \lipsum[1]
\end{SoftwareBreak}

\end{document}