# $Id: INotifyable.py,v 1.4.2.1 2006/08/17 21:42:22 marcusva Exp $
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# Copyright (c) 2006, Marcus von Appen
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"""Notifier interface class for event-capable objects."""

class INotifyable (object):
    """INotifyable () -> INotifyable

    A notifier interface class for event-capable objects.

    The INotifyable class is an interface, which should be used by
    objects, that make use of events using the EventManager class. It
    declares a single method, notify(), which consumes the events the
    object listens to.

    A short example for consuming events:

    class EventObject (INotifyable):
        def __init__ (self):
            ....
        def notify (self, event):
            if event.signal == 'EventObjectSignal':
                self.do_certain_action ()
            ...
    """
    def notify (self, event):
        """I.notify (...) -> None
        
        Notifies the object about an event.

        This method has to be implemented by inherited classes. Its
        signature matches the basic requirements of the EventManager
        class.
        """
        raise NotImplementedError