perms.py 文件源码

def __iter__(self):
        tally = []
        values = (pair[1] for pair in self.of)
        keys = [pair[0] for pair in self.of]

        # evaluate any transformers in order
        for i, v in enumerate(values):
            if callable(v):  # then create a permutation for everything 
                for p in [x for x in AllPerms(*tally)]:
                    tally.append((keys[i], v(**p)))
            else:
                tally.append((keys[i], v))

        values = (pair[1] for pair in tally)

        for tup in itertools.product(*values):
            yield dict(zip(keys, tup))