Monad explained in one picture

标签：margin   elf   mon   and   eid   abi   style   display   block   

The whole point of Monad is composability. In the category in green, T -> Monad<U> and U -> Monad<R> are not composable. With the help of fmap and join, we map them in to the category in blue (actually the category itself), they become composable.

Monad explained in one picture

标签：margin   elf   mon   and   eid   abi   style   display   block   

原文地址：http://www.cnblogs.com/weidagang2046/p/monad-explained-in-one-picture.html