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# Copyright (c) 2002 Zope Corporation and Contributors.
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# This software is subject to the provisions of the Zope Public License,
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"""Dependable framework interfaces

$Id: interfaces.py 67630 2006-04-27 00:54:03Z jim $
"""
__docformat__ = 'restructuredtext'

from zope.interface import Interface
from zope.exceptions.interfaces import UserError

class IDependable(Interface):
    """Objects that other objects depend on.

    Note that `IDependable` will normally be implemented by an adapter.
    """

    def addDependent(location):
        """Add a dependency to a dependent object by location

        The location is the physical path to the dependent object.
        """
    def removeDependent(location):
        """Remove a dependency with a dependent object by location.

        The location is the physical path to the dependent object.
        """
    def dependents():
        """Return a sequence of dependent object locations.
        """

class DependencyError(UserError):
    """ This object is dependable"""