Will Robertson wrote: > I'm more in favour of having the single letter with a possible optional > default. > I still think that { o } and { o{default} } make the most sense. Well, in a way so do I (it was my suggestion :-)) > I like this way of doing coordinates. Could 'd{}{-default-}' be > shoe-horned into this syntax as well? I suppose that would mean > completely re-writing the parser. But then we wouldn't need another > letter for my feature of limited value. I thought about this. There is an issue, though. For a standard delimited argument, the two "ends" are arbitrary: [) will work as well as []. You can easily pick up: d{ ... for the opening-group token, but in this case you have to have a closing group token as the closing token (both for d{} and for gathering the argument). So d[]{default} and d{}{default} are subtly but importantly different. I'm not opposed, though: "d{}{<default>} can be used to include an optional argument surrounded by braces. Note that in this case the closing token *must* be a close-group token (usually `}')." -- Joseph Wright