calling objects

var dice = {
   sides: 6,
   roll: function(){
      return Math.floor(Math.random() * dice.sides) + 1;
   }
}

As far as syntax is concerned for this code, you can't use dice() because it would refer to a function and dice is an object.

Even if syntax weren't an issue, the underlying problem is objects can contain multiple properties. The compiler has no way of knowing what you want to get from inside dice. It looks obvious to you because there's one function, but what if we had ten? There has to be a clear way of telling the compiler which property we need. This is why we use dot notation.

//Get the roll method from dice.
dice.roll();

//Get the number of sides from dice.
dice.sides;

If you really wanted to use dice() you could make dice a function constructor and have it return the roll function. The downside to this is you cannot interact with it in any other way. This is much more complex than using just an object, and I don't recommend it unless you have a purpose to set it this way. You'll learn about constructors later on in this course, but it won't get to this degree.

/*** Dice Constructor ****/
var Dice = function(){

   var that = this;

   this.sides = 6;
   this.roll = function(){
      return Math.floor(Math.random() * that.sides) + 1;
   }

   return this.roll;
}



//create a new dice object.
var dice = new Dice();

//access the roll from dice.
console.log(dice());

//Throws an error because dice refers to the roll function and not itself.
console.log(dice.sides);