[Python-Dev] Re: PEP 218 (sets); moving set.py to Lib

Tim Peters tim_one@email.msn.com
Wed, 21 Aug 2002 01:25:42 -0400

[Guido, retroactively channeling Tim]
> A few transformations down the road, here's a 4-line powerset() generator:
> def powerset(base):
>     pairs = [(2**i, x) for i, x in enumerate(base)]
>     for n in xrange(2**len(pairs)):
>         yield [x for m, x in pairs if m&n]

Mine used one less local variable, so is more cache-friendly <wink>.