June 26, 2002 - Defining a Polymorphic Function

June 26, 2002 Defining a Polymorphic Function Tips: June 2002 Yehuda Shiran, Ph.D. Doc JavaScript

The function WriteNameValue() accepts a name and a value as parameters, and prints them. The name is a string and the value is defined of type Object. In this way, the value parameter can be substituted with any type. The implementation of this utility function is based on the system's polymorphic method, ToString(). You can write your own implementation, making sure you handle each and every type correctly. Here is the code:

   // compile with: jsc writename.js
   function WriteNameValue(name : String, value : Object) : void {
     print(name + value.ToString());
   }
   var o : Object = new Object();
   var i : int    = 9;
   var d : double = 5.8;
   var b : Base = new Base();
   WriteNameValue("o: ", o);
   WriteNameValue("i: ", i);
   WriteNameValue("d: ", d);
   WriteNameValue("b: ", b);
 
   class Base {
    protected var i : int = 5;
    public function ToString() : String {
    print("i is " +  i);
	return("foo");
  }
}