new tasks

Task/Delegates/JavaScript/delegates.js

@@ -0,0 +1,25 @@
+function Delegator() {
+  this.delegate = null ;
+  this.operation = function(){
+    if(this.delegate && typeof(this.delegate.thing) == 'function')
+      return this.delegate.thing() ;
+    return 'default implementation' ;
+  }
+}
+
+function Delegate() {
+  this.thing = function(){
+    return 'Delegate Implementation' ;
+  }
+}
+
+function testDelegator(){
+  var a = new Delegator() ;
+  document.write(a.operation() + "\n") ;
+
+  a.delegate = 'A delegate may be any object' ;
+  document.write(a.operation() + "\n") ;
+
+  a.delegate = new Delegate() ;
+  document.write(a.operation() + "\n") ;
+}