classof for CoffeeScript

gistfile1.coffee

## ----- classof.coffee ----- ##

_classof = (o) ->
  if o is null
    'Null'
  else if o is undefined
    'Undefined'
  else
    Object.prototype.toString.call(o).slice(8,-1)


module.exports = classof = (o) ->
  klass = _classof(o)
  if klass in ['Null', 'Undefined', 'Window']
    klass
  else
    Klass = eval(klass)
    if o.toString is Klass.prototype.toString
      klass
    else
      o.toString().slice(8,-1)

## ----- Now load it as a module ----- ##

classof = require './classof'

class MyClass
  getFnName: (fn) ->
    fn.name or fn.toString().match(/function\s*([^(]*)\(/)[1]

  toString: -> '[object ' + @getFnName(@constructor) + ']'

class Other extends MyClass

class Another extends Other

hiThere = new Another

classof hiThere is 'Another' # true

class YetAnother extends Another
  constructor: (@someprop) ->
    @initialize()

  initialize: ->
    if (classof @someprop) isnt 'MyClass' then throw 'an error' # I'm requiring @someprop to be an instance of MyClass

inst1 = new YetAnother [] # throws an error

inst2 = new YetAnother (new MyClass) # works okay