What is the best way to fake Classes in JavaScript?

Question

is there a better way to fake classes with private members in JavaScript?
function Animal(name) {
// private
var age = 1;
// public
this.name = name;
this.getAge = function() {
return age;
}
this.celebrateBirthday() {
age++;
}
}
var cat = new Animal('Kitty');
cat.celebrateBirthday();
console.log(cat.age); // undefined
console.log(cat.getAge()); // 2
pro: private is not accessible from outside
con: no chance for inheritance /testing.
thanks!

Answer 1

You can actually define classes in JavaScript:
https://developer.mozilla.org/es/docs/Web/JavaScript/Referencia/Classes
And although JS does not have native private functionality, you can use closures instead:
https://developer.mozilla.org/en-US/Add-ons/SDK/Guides/Contributor_s_Guide/Private_Properties