type APPLY :: forall a b. (a -> b) -> a -> btype APPLY f a = f a

Polymorphic Type application

For example...

APPLY Maybe Int == Maybe $ Int == Maybe Int

#type ($)

Operator alias for Type.Function.APPLY (right-associative / precedence 0)


type FLIP :: forall a b. a -> (a -> b) -> btype FLIP a f = f a

Reversed polymorphic Type application

For example...

FLIP Int Maybe == Maybe Int

Note: an infix for FLIP (e.g. Int # Maybe) is not allowed. Before the 0.14.0 release, we used # Type to refer to a row of types. In the 0.14.0 release, the # Type syntax was deprecated, and Row Type is the correct way to do this now. To help mitigate breakage, # Type was made an alias to Row Type. When the # Type syntax is fully dropped in a later language release, we can then support the infix version: Int # Maybe.