     @_indexOfKeys = -2
     @_ended = true
 
-  endSync: ->
+  freeSync: ->
     if @_indexOfKeys?
       return @_endKeys()
     else if @_endSync

    else
      @_ended = true
      @_end callback

        callback.apply null, arguments
    @

  free: (callback) ->
    throw new InvalidArgumentError("end() requires a callback argument")  unless typeof callback is "function"
    return callback(new AlreadyEndError("end() already called on iterator"))  if @_ended
    if @_indexOfKeys?
