See https://github.com/jgm/pandoc/issues/2956
Alternatively, in the dev version of pandoc you can tell
it you've got raw latex, not Markdown:
header-includes:
- `\let\oldsection\section`{=latex}
Final remark: I don't understand why it's not parsing
the `\section` as raw tex. I'll need to look into this;
it may be a bug in the LaTeX reader.
+++ David Nebauer [Aug 07 17 00:39 ]:
> If I process this markdown file ('mwe-latex.md'):
> ---
> title: "Minimal Working Example"
> header-includes:
> - \let\oldsection\section
> - \renewcommand{\section}[1]{\clearpage\oldsection{#1}}
> ---
> Text.
> with the pandoc command:
> pandoc -t latex --latex-engine=xelatex --output=mwe-latex.pdf
> mwe-latex.md
> I get the the error:
> ! LaTeX Error: Missing \begin{document}.
> See the LaTeX manual or LaTeX Companion for explanation.
> Type H <return> for immediate help.
> ...
> l.49 \let\oldsection\textbackslash{}s
> pandoc: Error producing PDF
> On generating latex output with the command:
> pandoc -t latex --latex-engine=xelatex --standalone
> --output=mwe-latex.tex mwe-latex.md
> and examining line 49 of the output file it becomes apparent that this
> line from the header inclusion:
> \let\oldsection\section
> has been munged by pandoc to:
> \let\oldsection\textbackslash{}section
> and this is causing the processing problem. (Note: changing latex
> engines makes no difference.)
> Once line 49 is edited to resemble the original command from the header
> inclusion the error disappears.
> How can I prevent this latex command in the header inclusion from being
> munged by pandoc?
>
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