CoffeeScript implementation of Python-like decorators

math.coffee

class window.EasyMath

  # decorators
  remember_last_result = (func) -> ->
    @last_result = func.apply(@, arguments)

  verify_number = (func) -> (args...) ->
    if args.some((arg) -> typeof arg isnt 'number')
      throw new Error('Numbers, idiot.')
    func.apply(@, arguments)


  last_result: null

  add: remember_last_result verify_number (num1, num2) ->
    num1 + num2

  subtract: remember_last_result verify_number (num1, num2) ->
    num1 - num2

  divide: remember_last_result verify_number (num1, num2) ->
    num1 / num2

  multiply: remember_last_result verify_number (num1, num2) ->
    num1 * num2

  max: remember_last_result verify_number (numbers...) ->
    Math.max.apply(null, numbers)