cats

Function: map[A, B](F[A])(A => B): F[B]
Monad[M[_]]



In [1]:

    
classpath.add(
  "org.typelevel" %% "cats-core" % "1.0.0-RC1"
);









    



4 new artifact(s)






    



4 new artifacts in macro
4 new artifacts in runtime
4 new artifacts in compile



In [6]:

    
import cats._, cats.instances.all._









    





import cats._, cats.instances.all._



In [7]:

    
val len: String => Int = _.length









    





len: String => Int = <function1>



In [8]:

    
Functor[List].map(List("scala", "cats")) (len)









    





res7: List[Int] = List(5, 4)



In [20]:

    
Functor[List].map(List[Int](1, 2, 3)) (_ / 2L)









    





res19: List[Long] = List(0L, 1L, 1L)



In [21]:

    
import cats.syntax.functor._









    





import cats.syntax.functor._



In [24]:

    
List("s", "cats").fproduct(len)









    





res23: List[(String, Int)] = List(("s", 1), ("cats", 4))

To be continued...