9 Jun
2003
9 Jun
'03
1:03 a.m.
In article <oqn0gue5cv.fsf@premise.demon.co.uk>, peter@premise.demon.co.uk (Peter G. Hancock) wrote:
I forget whether I've aired this on the list, but I'm seriously thinking = that we should change 'forall' to 'exists' in existential data constructors
Thanks! It made me wonder what colour the sky is on planet Haskell. From a Curry-Howard point of view, (I think) the quantifiers are currently the wrong way round. It is actually painful!
Well don't forget the other one: data MyType1 = forall a. MkMyType1 a; data MyType2 = MkMyType2 (forall a. a); You can put anything in a MyType1, but only something of type (forall a. a) such as "undefined" in a MyType2. -- Ashley Yakeley, Seattle WA