xargs is only needed if you have macros with optional arguments. Of course, \newcommand could handle the case with one optional. But, what we need in fact is something equivalent to \global\def for this case. Is there a way to do this with \newcommand?
Why \global?
I think that \global\newcommand works in any case.It would be nice to make the case "all optional arguments are before required ones" work with plain \newcommand.
JMarc
