if this == [None, None] and that == [None, None]:
				result = True
				break
		self.clear()
		other.clear()
		return(result)

	def __ne__(self, other):
		return(not self == other)

	def end(self):
		'''Returns last known point.'''
		end = None
		self.rewind()
		while True:
			this = self.pop()
			if this == [None, None]: