\docsvlist and \forcsvlist (from the etoolbox
package). The first uses the time-honoured LaTeX technique of
changing the definition of a \do command; it runs through the
list, and processes every item of the list as the argument of the
\do command; so:
\begin{itemize}
\renewcommand*{\do}[1]{\item #1}
\docsvlist{item1, item2, {item3a, item3b}, item4}
\end{itemize}
will convert the elements of a CSV list into an itemised list.
The macro \forcsvlist applies a function to each element of a
CSV list; this can of course be used to implement
\docsvlist, at the cost of a little clarity.
This answer was added: 2013-09-10
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