Module Lens

This module is undocumented. This is a list of its definitions.

Lens :: (a -> b) -> (b -> a -> a) -> Lens a b
get :: Lens a b -> a -> b

Reads through the lens the part of the given value that the lens focuses on.

set :: Lens a b -> b -> a -> a

set l b a returns a copy of a where the part that the lens l focuses on is replaced by b.