:: (c -> d) -> (a -> b -> c) -> a -> b -> d -package:pointless-fun -package:composition

Compose composed with compose operator.
(f ... g) x y === f (g x y)
Compose functions with one argument with function with two arguments. f .: g = \x y -> f (g x y).
Multivariable composition.
f .: g ≡ (f .) . g ≡ \c d -> f (g c d)
Wrap the result of a function applied to 2 arguments.