JavaScript/Notes/Singleton

Singleton with information hiding.

Lazy Initialization

<source lang="javascript"> function getAnObject(a) {

 var anObject;

 var b = a + 1;

 return (getAnObject = function() {
   if(! anObject ) {
     anObject = {name: b};
   }
   return anObject;
 })();

} </source>

Eager Initialization

Not a Singleton, but a constructor. <source lang="javascript"> // Not a Singleton. var c = function(a) {

 var b = a + 2;
 this.name = b;

};

var anObject = new c(); </source> Example: Constructors and prototype inheritance. jsbin

Singleton: <source lang="javascript"> var anObject = new function(a) {

 var b = a + 2;
 this.name = b;

}(3); </source> jsbin

Example: APE Animation Manager