many_to_one.py 文件源码

def _match_with_bipartite(
            self,
            subject_ids: MultisetOfInt,
            pattern_set: MultisetOfInt,
            substitution: Substitution,
    ) -> Iterator[Tuple[Substitution, MultisetOfInt]]:
        bipartite = self._build_bipartite(subject_ids, pattern_set)
        for matching in enum_maximum_matchings_iter(bipartite):
            if len(matching) < len(pattern_set):
                break
            if not self._is_canonical_matching(matching):
                continue
            for substs in itertools.product(*(bipartite[edge] for edge in matching.items())):
                try:
                    bipartite_substitution = substitution.union(*substs)
                except ValueError:
                    continue
                matched_subjects = Multiset(subexpression for subexpression, _ in matching)
                yield bipartite_substitution, matched_subjects