def bind_arguments(bind, args):
"""
arguments:
bind : function variable -> vertex set
args : {arg_name : [variable, ...], ...}
return value:
bound_args : {arg_name : vertex set, ...}
"""
result = {}
for arg_name, v_exprs in args.iteritems():
symbols = map(E.unpack_v, v_exprs)
subsets = map(bind, symbols)
result[arg_name] = set_union(subsets)
return result
def ancestors(self):
return set_union([parent.ancestors()
for parent in self.parents] + [{self}])
def descendents(self):
return set_union([chld.descendents()
for chld in self.children] + [{self}])
