def __init__(self, visitors, backend=None):
TraversalVisitor.__init__(self)
self.visit_order_dirty = True
self.visitor_instances = {}
self.visitors_by_name = {}
self.visit_order = []
self.backend = BackendCore() if backend is None else backend
for visitor_type, args in visitors.items():
self.add_visitor(visitor_type, args)
self.compile_visit_order()
def __init__(self, agg):
TraversalVisitor.__init__(self)
self.properties = agg
self.value = ydict(backend=agg)
