Traversable
Identity functor Constant functor Traversable functor Traversable functor laws Traversable functor - PS より・・・ foldMap/foldr 参考文献 Foldable and Traversable - Jakub Arnold Blog
記法 Category of applicative functors - PS Traversable functor その1 functor: natural transformation: *1 のペアで (unitality) (linearity) を満たすもの。 Traversable functor その2 functor: natural transformation: *2 のペアで (identity) (com…