Lists implemented as integer-hashed Dictionaries?

[Christian Heimes]

Stephen Hansen schrieb:
> Now, I believe Python sets *are* for all intents and purposes
> dictionaries, but I think that's just because its the easiest and most
> efficient way to implement their uniqueness properties; they took the
> very-well-tuned dictionary implementation and cut out the stuff not
> needed by sets and did some tweaks here or there. I /believe/.

You are correct. The first set implementation in pure Python was using a
dict as internal storage. The new set implementation is heavily based on
the highly optimized dict code. Sets are basically dicts without values.

from Objects/setobject.c

   set object implementation
   Written and maintained by Raymond D. Hettinger <python at rcn.com>
   Derived from Lib/sets.py and Objects/dictobject.c.