Hi chaps, Hugs (Feb 2001) fails to compile the following, complaining that the instances are not consistent with the dependencies: class Foo f a r | f a->r where foo::f->a->r instance Foo (a->r) (c a) (c r) instance Foo ((a,b)->r) (c a,c b)(c r) My intention is to overload the uncurried function foo for based on both its arity and the kind of tuple it is passed. Could you please explain what i am doing wrong here? Thank you so much, _______________________________ Jonathon Bell jbell@mathsoft.com MathSoft, Inc. www.mathsoft.com 101 Main St, Cambridge, MA 02142 (617) 577-1017 x745