state machine and a global variable

[tuom.larsen at gmail.com]

On Dec 14, 7:35 pm, Matimus <mccre... at gmail.com> wrote:
> On Dec 14, 8:52 am, tuom.lar... at gmail.com wrote:
>
>
>
> > Dear list,
> > I'm writing very simple state machine library, like this:
>
> > _state = None
>
> > def set_state(state):
> >     global _state
> >     _state = state
>
> > def get_state():
> >     print _surface
>
> > but I hate to use global variable. So, please, is there a better way
> > of doing this? All I want is that a user has to type as little as
> > possible, like:
>
> > from state_machine import *
> > set_state(3)
> > get_state()
>
> > I.e., nothing like:
> > import state_machine
> > my_machine = state_machine.new_machine()
> > my_machine.set_state(3)
> > my_machine.get_state()
>
> > Thanks, in advance!
>
> Personally I _would_ do it the second way. That seems to be the most
> appropriate way to do it. However, you can do it the second way and
> still get the functionality you desire.
>
> [code in state_machine.py]
> class StateMachine(object):
>     def __init__(self, state=None):
>         if state is None:
>             state = "DEFAULT_INIT_STATE"
>         self._state = state
>
>     def get_state(self):
>         # print self._surface
>         return self._state
>
>     def set_state(self, state):
>         self._state = state
>
> _sm = StateMachine()
> set_state = _sm.set_state
> get_state = _sm.get_state
> [/code]
>
> Matt


Thanks a lot! This is precisely what I had on my mind.