SHOW:
|
|
- or go back to the newest paste.
| 1 | package extension.monad | |
| 2 | ||
| 3 | trait Monad[A, M[_]] {
| |
| 4 | - | // >>= :: Monad m => m a -> (a -> m b) -> m b |
| 4 | + | // >>= :: Monad m => m a -> (a -> m b) -> m b |
| 5 | - | def flatMap[B](input: A => M[B]): M[B] // AKA "bind" |
| 5 | + | def flatMap[B](input: A => M[B]): M[B] // AKA "bind" |
| 6 | } | |
| 7 | ||
| 8 | trait Functor[A, F[_]] {
| |
| 9 | - | // fmap :: Functor f => (a -> b) -> f a -> f b |
| 9 | + | // fmap :: Functor f => (a -> b) -> f a -> f b |
| 10 | - | def map[B](input: A => B): F[B] // AKA "fmap" |
| 10 | + | def map[B](input: A => B): F[B] // AKA "fmap" |
| 11 | } | |
| 12 | ||
| 13 | object MOption {
| |
| 14 | implicit class MonadicOption[A](left: Option[A]) extends Monad[A, Option] with Functor[A, Option] {
| |
| 15 | def flatMap[B](right: A => Option[B]): Option[B] = left match {
| |
| 16 | case Some(x) => right(x) | |
| 17 | case None => None | |
| 18 | } | |
| 19 | ||
| 20 | def map[B](right: A => B): Option[B] = left match {
| |
| 21 | case Some(x) => Some(right(x)) | |
| 22 | case None => None | |
| 23 | } | |
| 24 | } | |
| 25 | } |
