Merge pull request #4146 from atais/ifF

added ifF to Functor
typelevel · Mar 16, 2022 · 219fcfb · 219fcfb
2 parents 65e7499 + fff0a3d
commit 219fcfb
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diff --git a/core/src/main/scala/cats/syntax/functor.scala b/core/src/main/scala/cats/syntax/functor.scala
@@ -4,6 +4,9 @@ package syntax
 trait FunctorSyntax extends Functor.ToFunctorOps {
   implicit final def catsSyntaxFunctorTuple2Ops[F[_], A, B](fab: F[(A, B)]): FunctorTuple2Ops[F, A, B] =
     new FunctorTuple2Ops[F, A, B](fab)
+
+  implicit final def catsSyntaxIfF[F[_]](fa: F[Boolean]): IfFOps[F] =
+    new IfFOps[F](fa)
 }
 
 final class FunctorTuple2Ops[F[_], A, B](private val fab: F[(A, B)]) extends AnyVal {
@@ -62,3 +65,19 @@ final class FunctorTuple2Ops[F[_], A, B](private val fab: F[(A, B)]) extends Any
    */
   def unzip(implicit F: Functor[F]): (F[A], F[B]) = F.unzip(fab)
 }
+
+final class IfFOps[F[_]](private val fa: F[Boolean]) extends AnyVal {
+
+  /**
+   * Lifts `if` to Functor
+   *
+   * Example:
+   * {{{
+   * scala> import cats.syntax.all._
+   *
+   * scala> List(true, false, false).ifF(1, 0)
+   * res0: List[Int] = List(1, 0, 0)
+   * }}}
+   */
+  def ifF[B](ifTrue: => B, ifFalse: => B)(implicit F: Functor[F]): F[B] = F.ifF(fa)(ifTrue, ifFalse)
+}
diff --git a/tests/src/test/scala/cats/tests/SyntaxSuite.scala b/tests/src/test/scala/cats/tests/SyntaxSuite.scala
@@ -284,6 +284,9 @@ object SyntaxSuite {
 
     val b = mock[B]
     val fb1: F[B] = fa.as(b)
+
+    val c = mock[F[Boolean]]
+    c.ifF(1, 0)
   }
 
   def testApply[F[_]: Apply: Semigroupal,