Re: About `<prefix>--' (was Re: filenotify.el)

[Stefan Monnier]

> Agreed.  XOR is also an example.  Some generally useful features have
> been added to core Emacs Lisp recently (e.g., generalized variables),

Notice that these are language features, whereas powerset is in
a different category of "occasionally useful library function".

We sadly don't have a good place to put such generic functions.
Maybe we could create a new "set" library of set functions
(union, intersection, difference, powerset, membership, negation, ...).


        Stefan