How to remove Uncaught TypeError: Cannot read property 'idAttribute' of undefined in Backbone Collection?

Question

backbone.js

Coffeescript code:

UserNameModel =
  # idAttribute: 'id'
  defaults:
    "Name": ""

ProjectGroup = Backbone.Collection.extend
  model: UserNameModel
  checkUser: (username) ->
    findResult = @find (user) -> user.get "Name" == username
    findResult != null

SE1 = new ProjectGroup [
  {id: 1, Name: "Artem"}
  {id: 2, Name: "Airat"}
  {id: 3, Name: "Vlad"}
  {id: 4, Name: "Maxim"}
  {id: 5, Name: "Igor"}
]

On startup, Uncaught TypeError: Cannot read property 'idAttribute' of undefined, points to the line where SE1 is created.
How to make the code work?

Answer 1

First, idAttribute must be specified on the model, not on the collection.
Secondly, if you have it equal to 'id', then you do not need to specify it at all - this is the default value.