I have a class in coffeescript a class layout like the following.

class @A
  foo: ->
    console.log('foo')

class @B extends A
  fooB: ->
      @foo()

class @C extends B
  fooC: ->
      @foo()  

I tried this in interpreters, it works. However it raises errors, when executing this in the browser (all of them are in separate coffee files, and are used in a global context. Therefore the @ before the class):

Uncaught ReferenceError: B is not defined application.js

It seems that B is defined after the definition of C. How can this happen?