[texhax] optionally compiling parts of a document

[Uwe Lück]

> "Neal H. Walfield" <neal at walfield.org> wrote:
> An: texhax at tug.org
> Betreff: [texhax] optionally compiling parts of a document
> Hi,
> 
> The document that I'm working on now takes about a minute to typeset.
> I want to improve this by only compiling a subset of the chapters. I
> know about breaking the document into multiple files and using
> \includeonly to only select a subset of the chapters, but I like
> having a single file. I thought that I could get the same effect
> using the filecontents package. I've written some macros that appear
> to do what I want, but the file inclusion results in an "infinite"
> loop. 

Maybe this is just another poor guess ...

> Here's the output of the attached example:
> 
> LaTeX Warning: Overwriting file `./b-segment-1.tex'.
> 
> 
> LaTeX Warning: Overwriting file `./b-segment-2.tex'.
> 
> (./b-segment-2.tex
> 
> ! LaTeX Error: \include cannot be nested.
> 
> See the LaTeX manual or LaTeX Companion for explanation.
> Type H <return> for immediate help.
> ...
> 
> l.1
> 
> I think that the problem has something to do with the interaction of
> \filecontents and \include. If I replace the \include with just some
> text, it seems to work fine.
> [...]
> Here is a minimal example using my macros:

It seems to me that you are confusing \include with \input, 
trying to issue \include conditionally. Instead, you still must issue 
\include for /each/ "segment" (chapter). What to "actually include" 
is controlled by \includeonly. So your "segment" macro only should 
determine the file name. Separately from that, you must transform 
\segmentsToInclude into the proper input for the \includeonly macro, 
which must happen in the document preamble already.

It appears to me that the main difficulty with your idea is 
that you want to refer to the "segments" by something different 
from their file names, I cannot help you with that tonight ...

Cheers, 

    Uwe.

> \documentclass{report}
> 
> \usepackage{lipsum}
> \usepackage{filecontents}
> \usepackage{tikz}
> 
> % The segments to include in the document. If empty or undefined, all
> % segments are included.
> \def\segmentsToInclude{chapter 2, 3}
> 
> \def\segmentcount{0}
> % Create a segment of text, which is only included in the compiled
> % document if its name or segment index is in \segmentsToInclude.
> %
> % \begin{segment}{name}
> % text.
> % \end{segment}
> %
> % If name is empty, then a name will be assigned automatically.
> \newenvironment{segment}[1]{%
> % #1 is optional in the sense that it can be empty, but it is
> % required because otherwise TeX starts to convert the text into
> % tokens, which we need to avoid.
> \xdef\segmentname{#1}%
> %
> % Increment the segment count macro.
> \pgfmathparse{\segmentcount + 1}
> % Save the result. Note: \pgfmathresult is 'XXX.0'. Strip the
> % trailing .0.
> \def\nozerohelper##1.0{##1}%
> \def\nozero##1{\expandafter\nozerohelper##1}%
> \xdef\segmentcount{\nozero{\pgfmathresult}}%
> %
> % If the provided segment name is empty, use the segment's offset.
> \def\empty{}%
> \ifx\segmentname\empty%
> \xdef\segmentname{\segmentcount}%
> \fi%
> %
> % The segment's filename.
> \xdef\segmentsfilename{\jobname-segment-\segmentcount}%
> %
> % Write out the segment's contents.
> \filecontents{\segmentsfilename.tex}%
> }{%
> % Include the segment if appropriate.
> \def\empty{}%
> \def\doinclude{\include{\segmentsfilename}}%
> %\def\doinclude{including \segmentsfilename}%
> \expandafter \ifx \csname segmentsToInclude\endcsname \relax
> % \segmentsToInclude is undefined. Include the segment.
> \doinclude%
> \else%
> \ifx\segmentsToInclude\empty%
> % \segmentsToInclude is empty. Include the segment.
> \doinclude%
> \else%
> \foreach \i in \segmentsToInclude {%
> % Determine whether to include the segment.
> \def\includep{}%
> \ifx \i\segmentname%
> % The segment's name is in \segmentsToInclude. Include the
> % segment.
> \def\includep{1}%
> \fi%
> \ifx \i\segmentcount%
> % The segment's index is in \segmentsToInclude. Include the
> % segment.
> \def\includep{1}%
> \fi%
> %
> \ifx \includep\empty%
> \else%
> \doinclude%
> \breakforeach%
> \fi%
> }%
> \fi%
> \fi%
> }
> 
> \begin{document}
> 
> \begin{segment}{}
> \chapter{One}
> 
> Start of chapter one.
> 
> \lipsum[1-10]
> 
> End of chapter one.
> 
> \end{segment}
> 
> \begin{segment}{chapter 2}
> \chapter{Two}
> 
> Start of chapter two.
> 
> \lipsum[11-20]
> 
> End of chapter two.
> 
> \end{segment}
> 
> \begin{segment}{}
> \chapter{Three}
> 
> Start of chapter three.
> 
> \lipsum[21-30]
> 
> End of chapter three.
> 
> \end{segment}
> 
> \end{document}