ApplicativeError: add raiseOption operation.

typelevel · Mar 20, 2020 · 92031da · 92031da
1 parent f28136c
commit 92031da
Showing 1 changed file with 21 additions and 0 deletions.
diff --git a/core/src/main/scala/cats/ApplicativeError.scala b/core/src/main/scala/cats/ApplicativeError.scala
@@ -273,6 +273,27 @@ trait ApplicativeError[F[_], E] extends Applicative[F] {
       case None    => raiseError(ifEmpty)
     }
 
+  /**
+   * Convert from scala.Option when the content is a value of the error type.
+   * If the option is empty, an empty unit effect is given.
+   * If the option contains an error, it is raised.
+   *
+   * Example:
+   * {{{
+   * scala> import cats.implicits._
+   * scala> import cats.ApplicativeError
+   * scala> val F = ApplicativeError[Either[String, *], String]
+   *
+   * scala> F.raiseOption(Option.empty[String])
+   * res0: scala.Either[String, Unit] = Right(())
+   *
+   * scala> F.raiseOption(Option("Failed"))
+   * res1: scala.Either[String, Unit] = Left("Failed")
+   * }}}
+   */
+  def raiseOption(oe: Option[E]): F[Unit] =
+    oe.fold(unit)(raiseError)
+
   /**
    * Convert from cats.data.Validated
    *