JavaScript/Notes/Singleton

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Singleton with information hiding.

Lazy Initialization

function getAnObject(a) {
  var anObject;
 
  var b = a + 1;
 
  return (getAnObject = function() {
    if(! anObject ) {
      anObject = {name: b};
    }
    return anObject;
  })();
}

Eager Initialization

Not a Singleton, but a constructor.

// Not a Singleton.
var c = function(a) {
  var b = a + 2;
  this.name = b;
};
 
var anObject = new c();

Example: Constructors and prototype inheritance. jsbin

Singleton:

var anObject = new function(a) {
  var b = a + 2;
  this.name = b;
}(3);

jsbin

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