| 116 | |
| 117 | |
| 118 | def all_partial_orderings(tuples, elements): |
| 119 | edges = defaultdict(set) |
| 120 | for parent, child in tuples: |
| 121 | edges[child].add(parent) |
| 122 | |
| 123 | def _all_orderings(elements): |
| 124 | if len(elements) == 1: |
| 125 | yield list(elements) |
| 126 | else: |
| 127 | for elem in elements: |
| 128 | subset = set(elements).difference([elem]) |
| 129 | if not subset.intersection(edges[elem]): |
| 130 | for sub_ordering in _all_orderings(subset): |
| 131 | yield [elem] + sub_ordering |
| 132 | |
| 133 | return iter(_all_orderings(elements)) |
| 134 | |
| 135 | |
| 136 | def function_named(fn, name): |