README

Traversable structures support element-wise sequencing of Applicative effects (thus also Monad effects) to construct new structures of the same shape as the input.

To illustrate what is meant by same shape, if the input structure is [a], each output structure is a list [b] of the same length as the input. If the input is a Tree<A>, each output Tree<B> has the same graph of intermediate nodes and leaves. Similarly, if the input is a tuple (x, a), each output is a tuple (x, b), and so forth.

Every Traversable structure is both a Functor and Foldable.