Pseudo-inheritance in JS

consumer.js

angular.module('otherModule', ['myModule'])
  .factory('consumer', function (myClass) {
    var instance1 = myClass(),
        instance2 = myClass(),
        instance3 = myClass();
      
    }})

consumer2.js

angular.module('otherModule', ['myModule'])
  .factory('consumer', function (mySingleton) {
    var instance = mySingleton;  
    }})

my-class.js

angular.module('myModule', [])
  .factory('myClass', function () {
    function myClass() {
      var d = {};
      
      d.myMethod = function (x) {
        return x + 5;
      }
      
      return d;
    }
    
    return myClass;
  });

my-class2.js

angular.module('myModule', [])
  .factory('mySingleton', function () {
    function myClass() {
      var d = {};
      
      d.myMethod = function (x) {
        return x + 5;
      }
      
      return d;
    }
    
    return myClass();
  });