Using before as a Global setting in enumitem

Question

I am working on a small project and am using the enumitem package reasons for beyond this example. I read the docs and managed to produce this example. Currently, I am using the before argument on the \begin{description} (uncomment part of line 6).

To facilitate reuse I would like to move it into the global settings for description the description environment (line 4). However, it appears to be beyond my understanding.

Thanks for the help

\documentclass{article}
  \usepackage{enumitem}

  %\setlist[description]{before={\renewcommand{\makelabel}[1]{\textit{##1}: }}} % Illegal parameter number in definition of \enit@@description.
  \begin{document}
    \begin{description}%[before={\renewcommand{\makelabel}[1]{\textit{##1}: }}]
      \item[square]{a four-sided polygon is a square if and only if all sides are equal and its vertex angles are all right angles.}
    \end{description}
  \end{document}

Maybe I'm missing something here, but why don't you just use \setlist[description]{font=\normalfont\itshape} rather than using the before code? — Alan Munn, Jun 01 '13 at 20:52

Alan Munn · Accepted Answer · 2013-06-01T21:38:39.593

If your goal is simply to change the formatting of the description label, then you shouldn't be using the before argument at all, but instead just specifying the format for the label. If you're just changing font properties you can use the font argument (e.g. font=\normalfont\itshape) If you want to add material to the label (as you state in the comment), the best way to do that is to make a command to add the colon (or do any other formatting you want) and use that command as the last in the format argument. There should generally be very little need for the before argument with respect to formatting the parts of the list itself.

\documentclass{article}
\usepackage{enumitem}
\newcommand\addcolon[1]{#1:}
\setlist[description]{format=\normalfont\itshape\addcolon}.
\begin{document}
  \begin{description}
    \item[square]{a four-sided polygon is a square if and only if all sides are
     equal and its vertex angles are all right angles.}
  \end{description}
\end{document}

That is noted, but I am also adding characters after the label (colon in the example). — Ra is dead, Jun 01 '13 at 21:29

score 2 · Answer 2 · answered Jun 01 '13 at 20:48

2

The package apparently passes that argument through three levels of macro definition so you need

\documentclass{article}
  \usepackage{enumitem}

  \setlist[description]{before={\renewcommand{\makelabel}[1]{\textit{########1}: }}} % Illegal parameter number in definition of \enit@@description.
  \begin{document}
    \begin{description}%[before={\renewcommand{\makelabel}[1]{\textit{##1}: }}]
      \item[square]{a four-sided polygon is a square if and only if all sides are equal and its vertex angles are all right angles.}
      \item[square]{a four-sided polygon is a square if and only if all sides are equal and its vertex angles are all right angles.}
    \end{description}
  \end{document}

answered Jun 01 '13 at 20:48

David Carlisle

757,742

Wow! Is there a good way to find that out other than just reading the code or guessing? – Ra is dead Jun 01 '13 at 20:51
@Raisdead In this case, I just doubled them till it worked (it helps to know that that process will terminate:-) You could read the code and work it out, or the package could have been written not to require doubling #. – David Carlisle Jun 01 '13 at 20:54
@Raisdead See Why do paramaters of \renewcommand need to double up the # within a \foreach for some nice discussion of this. (Also by David). – Alan Munn Jun 01 '13 at 20:55
@AlanMunn Thanks for that reference. I'll be sure to read it thoroughly. – Ra is dead Jun 01 '13 at 21:00

Using before as a Global setting in enumitem

2 Answers2