from utils.value import AttributeChange


class Connectable(AttributeChange):
	"""Observable hardware-connection state shared by AHeater/AStirrer.

	Simulated devices are always connected; real (serial) devices start
	disconnected and only flip once connect() actually reaches the
	hardware.
	"""

	def __init__(self, simulated):
		AttributeChange.__init__(self)
		self.simulated = simulated
		self.connected = simulated

	def connect(self):
		return self.connected

	def disconnect(self):
		pass