data Sum : Rel a -> Rel a -> Rel aSum / Either of relations (linear!)
bimapOnce : {0 f : a -> b} -> p x y -@ r (f x) (f y) -> q x y -@ s (f x) (f y) -> Sum p q x y -@ Sum r s (f x) (f y)Linear 'bimap'
bimap : {0 f : a -> b} -> (p x y -> r (f x) (f y)) -> (q x y -> s (f x) (f y)) -> Sum p q x y -> Sum r s (f x) (f y)Transform relationships