root/cpsskins/branches/jmo-perspectives/ontology.py

##############################################################################
#
# Copyright (c) 2005-2006 Nuxeo and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""

$Id$
"""
__docformat__ = "reStructuredText"

from zope.component import getUtilitiesFor
from zope.interface import implements, Interface

from cpsskins.relations import Predicate, CompoundPredicate, ProxyPredicate

# Monadic predicates

isDefault = Predicate('_ is default')

# Dyadic predicates

hasDisplay = Predicate('_ has display _')
hasPortlet = Predicate('_ has portlet _')

# Triadic predicates

hasPortletFromPerspective = Predicate('_ has portlet _ from perspective _')
hasDisplayFromPerspective = Predicate('_ has display _ from perspective _')

# Compound predicates

# Formats

class IFormatPredicate(Interface):
    """A predicate used by a format"""

class FormatPredicate(object):
    """A predicate used by a format
    """
    implements(IFormatPredicate)

    def __init__(self, predicate):
        self.predicate = predicate

def hasFormatProxy():
    return CompoundPredicate(
        tuple([v.predicate for k, v in getUtilitiesFor(IFormatPredicate)]
        ))

hasFormat = ProxyPredicate(hasFormatProxy)