comma-separated listmacros
I have a macro accepting several optional arguments in a comma separated list.
I would like to assign a value containing a comma to a particular argument. Is there a way to "escape" this particular comma so that it will not be interpreted as the beginning of a new argument.
Here is an except of what I would like to achieve:
\begin{mymacro}[arg1=a,b,arg2=c]
% ...
\end{mymacro}
I would like to set arg1 to a,b and not, of course, seeing this interpreted as "arg1=a and b".
Thanks!
This is similar to @egreg's solution and avoids \ifcase in favour of just cycling the list, but the coding is probably a bit simpler (unless you'be already loaded expl3 for other reasons)
\documentclass{article}
\usepackage{xcolor}
\def\ColorList#1{\def\xcolorlist{#1}}
\let\xsection\section
\def\section{\expandafter\xxcycle\xcolorlist,\xcolorlist\xsection}
\def\xxcycle#1,#2{%
\ifx\relax#1\relax\else
\color{#1}%
\ifx\xcolorlist#2\else
\xcycle#1,#2%
\fi
\fi}
\def\xcycle#1,#2\fi\fi#3\xcolorlist{\fi\fi\ColorList{#2#3#1}}
\ColorList{yellow,magenta,cyan,orange,blue,green!30,red!50!black}
%\ColorList{yellow}
%\ColorList{}
\begin{document}
\section{Title}
\section{Title}
\section{Title}
\section{Title}
\section{Title}
\section{Title}
\section{Title}
\section{Title}
\section{Title}
\end{document}
etoolbox's list processing capabilities are straight forward:
\documentclass{article}
\usepackage{etoolbox}% http://ctan.org/pkg/etoolbox
\newcommand{\ppath}[2][$\;\triangleright\;$]{%
\def\nextitem{\def\nextitem{#1}}% Separator
\renewcommand*{\do}[1]{\nextitem\textsf{##1}}% How to process each item
\docsvlist{#2}% Process list
}
\begin{document}
A decent file path is \ppath{File,New,Document}.
\end{document}
The separator \nextitem is defined to do nothing during its first use. \do defines how each item is processed, while \docsvlist processes a comma-separated list. See Cunning (La)TeX tricks for a short discussion on the use of \nextitem.
Best Answer
Well I guess that was a trivial question...
The answer is:
@Qrrbrbirlbel: thanks.