OO JavaScript调用同一对象的另一种方法的方法

Question

I'm having trouble calling a method from within another method of the same object.

Any help on what I may be missing, or what to look for, would be greatly appreciated.

var IceCream = function (flavor) {
  this.tub = 100;
  this.flavor = flavor;
};

IceCream.prototype = { 
        scoop : function () {
            this.updateInventory; alert("scooping");
        },
        updateInventory : function () {
            this.tub --;
        alert(this.tub);
        }
};

 var vanilla = new IceCream("vanilla");
 vanilla.scoop();

Answer 1

Convert this

 this.updateInventory;

to this

 this.updateInventory();

DEMO