request: MultiMap

[haskell at alias.spaceandtime.org]

> I suggest you try "Map key (Set value)" with DData.
> A number of functions are there to help you to
> implement multimap semantics. (i.e. unionWith, adjust)

This is exactly what I'm currently doing.  But it would be nice to have
in the libraries.  MultiSet is easily emulated as well, but it's there.

> With the scheme I described eariler, it is rather
> trivial to implement; (almost) all you need is to
> rename functions.

Are you suggesting I implement it for the libraries, or for myself?  If
it's the former, trust me, you don't want *me* doing that. :)  If it's
the latter, I have, in some part, but it's a pain and distracts me from
my primary goal.

Thanks,

James