Private members in CoffeeScript?

Question

Does somebody know how to make private, non-static members in CoffeeScript? Currently I\'m doing this, which just uses a public variable starting with an underscore to clari

Answer 1

"class" in coffee scripts leads to an prototype based result. So even if you use a private variable it is shared between instances. You can do this:

EventEmitter = ->
  privateName = ""

  setName: (name) -> privateName = name
  getName: -> privateName

.. leads to

emitter1 = new EventEmitter()
emitter1.setName 'Name1'

emitter2 = new EventEmitter()
emitter2.setName 'Name2'

console.log emitter1.getName() # 'Name1'
console.log emitter2.getName() # 'Name2'

But be careful to put the private members before the public functions, because coffee script returns the public functions as object. Look at the compiled Javascript:

EventEmitter = function() {
  var privateName = "";

  return {
    setName: function(name) {
      return privateName = name;
    },
    getName: function() {
      return privateName;
    }
  };
};