Y combinator: Difference between revisions

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 =={{header|Scala}}==
 Credit goes to the thread in [https://web.archive.org/web/20160709050901/http://scala-blogs.org/2008/09/y-combinator-in-scala.html scala blog]
-<lang scala>def Y[A,B](f: (A=>B)=>(A=>B)) = {
+<lang scala>
-  case class W(wf: W=>A=>B) {
+def Y[A, B](f: (A => B) => (A => B)): A => B = {
-    def apply(w: W) = wf(w)
+  case class W(wf: W => A => B) {
+    def apply(w: W): A => B = wf(w)
   }
-  val g: W=>A=>B = w => f(w(w))(_)
+  val g: W => A => B = w => f(w(w))(_)
   g(W(g))
+}
-}</lang>
+</lang>
 Example
+<lang scala>
-<lang scala>val fac = Y[Int, Int](f => i => if (i <= 0) 1 else f(i - 1) * i)
+val fac: Int => Int = Y[Int, Int](f => i => if (i <= 0) 1 else f(i - 1) * i)
 fac(6)  //> res0: Int = 720
-val fib = Y[Int, Int](f => i => if (i < 2) i else f(i - 1) + f(i - 2))
+val fib: Int => Int = Y[Int, Int](f => i => if (i < 2) i else f(i - 1) + f(i - 2))
-fib(6)  //> res1: Int = 8</lang>
+fib(6)  //> res1: Int = 8
+</lang>
 =={{header|Scheme}}==