# defining (-> Bool) as a set

**Hal Daume III
**
hdaume@ISI.EDU

*Mon, 22 Apr 2002 15:31:36 -0700 (PDT)*

I'd like to be able to define something like
instance Eq a => Coll (-> Bool) a where
empty = \_ -> False
single x = \y -> if x == y then True else False
union a b = \x -> a x || b x
insert s x = \y -> x == y || s y
and the like
However, this seems to be impossible. Is this the type lambda restriction
that's been discussed recently on the mailing list?
- Hal
--
Hal Daume III
"Computer science is no more about computers | hdaume@isi.edu
than astronomy is about telescopes." -Dijkstra | www.isi.edu/~hdaume