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Haskell's mapM equivalent for Scala cats

Does cats provide a function equivalent to mapM in Haskell? It should look like:

  def mapM[A, B, F[_], Col[_]]
  (col: Col[A])(f: A => F[B])(implicit F: Applicative[F], T: Traverse[Col]): F[Col[B]] = 
    T.sequence[F, B](F.map(col)(f))

Unfortunately I haven't found any function like this one =(

like image 349
Vitalii Honta Avatar asked Nov 15 '25 13:11

Vitalii Honta


1 Answers

It's called traverse:

scala> import cats.implicits._
import cats.implicits._

scala> List(1, 2, 3).traverse(n => Option((n * 2).toString))
res1: Option[List[String]] = Some(List(2, 4, 6))
like image 91
Kolmar Avatar answered Nov 18 '25 04:11

Kolmar