Documentation
class Field1 r a x y | r x -> y, r y -> x, r -> a, x y -> r where Source
Instances
Field1 (a, b) a (a -> a2 -> (a, b)) (X -> a2 -> (a, b)) | |
class Field2 r a x y | r x -> y, r y -> x, r -> a, x y -> r where Source
Instances
Field2 (a, b) b (a1 -> b -> (a, b)) (a1 -> X -> (a, b)) | |