Inheriting private member functions working in CoffeeScript, with .call()

gistfile1.coffee

# This is an example in a post about private members in CoffeeScript.
# Read more: http://evanhahn.com/?p=1126

class Sorcerer
  constructor: (@spell) ->
  conjureSpell = ->   # private
    @spell.conjure()
  useSpell: ->
    conjureSpell.call(this)
    @spell.use()

class Child extends Sorcerer
  constructor: (@spell) -> # Overriding the constructor

c = new Child
  conjure: -> console.log "Brewing potion..."
  use: -> console.log "Now I have superpowers!"

c.useSpell()

# This code by Evan Hahn (evanhahn.com) is licensed under the Unlicense.
# http://unlicense.org/