At 2002-06-06 03:38, Cagdas Ozgenc wrote:

Then either -> is not a type constructor,

(->) is a type constructor.

or the concept of type constructors has to be divided into two : consuming type constructors, and producing type constructors.

Type constructors can do anything they like with their arguments. Here are some of kind (* -> *): newtype Holds a = MkHolds a data Ignores a = MkIgnores newtype Wants a = MkWants (a -> Bool) data List a = MkPairList a (List a) | MkEmptyList data Maybe a = Just a | Nothing I don't think you can divide them up into two categories... -- Ashley Yakeley, Seattle WA