> Actually, I even see a feature missing from CL, which is to get &rest
> arguments minus processed
> keyword arguments. (Hence Gauche supports it).
Do you mean that when allow-other-keys is given, those "other" keys and
their values end up in their own association list?
Yes, Gauche allows an optional argument follows :allow-other-keys, which receives keyword-value list
that didn't match known keywords. Handy when you're writing a wrapper procedure that takes
additional keyword arguments; you process those additional keys then pass the rest to the
inner procedure.