Question

I have the following class:

var Person = Class.create({
  initialize: function(name) {
    this.name = name;
  },
  say: function(message) {
    return this.name + ': ' + message;
  }
});

If I’m to declare a new instance variable, do I have to explictly state the datatype?

Answer 1

JavaScript does not have datatype declarations. It’s been a while since I’ve used prototypejs, but I think you can do something like this:

var Person = Class.create({
  name: '',
  someOtherVariable: 1,

  initialize: function(name) {
    this.name = name;
  },
  say: function(message) {
    return this.name + ': ' + message;
  }
});

Using the variable without declaration (as in your code sample) will work, but it can be a bit more clear which properties are being used if they are also declared separately. Plus, you can give them default values this way.