4

I use three packages (in a latex "book" document) to display source files (not only tex and sometimes loaded from external files) and their outputs (sometimes loaded from external files) side by side.

  • listings for the syntax highlighting
  • paracol to display side-by-side
  • mdframed to customize appearance

My problem is, that this causes warnings of multiply defined labels (somewhere inside mdframed I think):

WARNING: Label 'mdf@pagelabel-1' multiply defined
WARNING: There were multiply defined labels

I hacked my way through, but I'm not satisfied with my solution... is there a better way?

Here is my minimal "working with warnings" example. My hacks are commented out (to use them toggle comment on the \switchcolumn command to).

\documentclass[]{book}

\usepackage{listings}
\usepackage{mdframed}
\usepackage{paracol}

\lstnewenvironment{insertcode}{\mdframed}{\endmdframed}

%-------------------------------------------------------
%\newcounter{mdfzrefhack}
%\setcounter{mdfzrefhack}{1}
%\newcommand{\swcsafe}{
%\switchcolumn
%\setcounter{mdf@zref@counter}{\value{mdfzrefhack}}
%\addtocounter{mdfzrefhack}{1}
%}
%=======================================================

%-------------------------------------------------------

\begin{document}

\begin{paracol}{2}
\begin{insertcode}
x
\end{insertcode}

%-------------------------------------------------------
%\swcsafe
%=======================================================
\switchcolumn
%-------------------------------------------------------

\begin{insertcode}
y
\end{insertcode}
\end{paracol}

\end{document}

Each of the modifications below (magically in some cases) make the warnings go away:

  • not using mdframed
  • changing the document type from book to minimal (for ex.)
  • shifting one of the listings a bit lower by placing some text above it in the column

Edited: made the example simpler, deleted PS (thanks to egreg)

UPDATE: I've just submitted this on the github of mdframed.

Community
  • 1
masu
  • 6,571

2 Answers2

5

You have to use the “internal” commands in \lstnewenvironment, instead of \begin{mdframed} and \end{mdframed}. This seems to work:

\documentclass[]{book}

\usepackage{listings}
\usepackage{mdframed}
\usepackage{paracol}

\lstnewenvironment{insertcode}{\mdframed}{\endmdframed}

\newcounter{mdfzrefhack}
\setcounter{mdfzrefhack}{1}
\newcommand{\swcsafe}{\switchcolumn
  \setcounter{mdf@zref@counter}{\value{mdfzrefhack}}%
  \addtocounter{mdfzrefhack}{1}%
}

\begin{document}

\begin{paracol}{2}
\begin{insertcode}
x
\end{insertcode}

\swcsafe

\begin{insertcode}
y
\end{insertcode}
\end{paracol}

\end{document}

enter image description here

I'd probably say

\lstnewenvironment{insertcode}[1][]
  {\lstset{#1}\mdframed}
  {\endmdframed}

so that additional listings options to insertcode can be set.

egreg
  • 1,121,712
  • Thanks, but this only answers my "PS", not the original question. Still it was a helpful info, but the problem stays. I'll edit my code according to your suggestion to leave out \Before... commands. And of course, I use a more complicated logic inside insertcode, but It was a minimal example so... – masu Sep 26 '13 at 10:17
3

Official answer from the mdframed package author and maintainer:

In your question you pointed out the correct issue. I think the simplest way is to use the option usetwoside=false:

\lstnewenvironment{insertcode}{\mdframed[usetwoside=false]}{\endmdframed}

In this case no check is done.

masu
  • 6,571