Javascript/Y_Combinator: Add

Author: GHScan

JavaScript/Y_Combinator/main.js

@@ -0,0 +1,36 @@
+'use strict'; 
+
+//------------------------------
+// Y combinator
+function Y(f) {
+    return (function(g) {
+        return g(g);
+    })(function(g) {
+        return f(function() { return g(g).apply(null, arguments); });
+    });
+}
+
+//------------------------------
+// via Y-combinator
+var f = Y(function(self) {
+    return function(n) {
+        return n < 2 ? n : self(n - 1) + self(n - 2);
+    }
+});
+
+// via function expression
+var f2 = (function f(n) {
+    return n < 2 ? n : f(n - 1) + f(n - 2);
+})
+
+// via expand function expression
+var f3 = (function () {
+    var f = function(n) {
+        return n < 2 ? n : f(n - 1) + f(n - 2);
+    };
+    return f;
+})();
+
+console.log(f(30));
+console.log(f2(30));
+console.log(f3(30));