[Python-Dev] Hashing proposal: change only string-only dicts

[Victor Stinner]

> Each string would get two hashes: the "public" hash, which is constant
> across runs and bugfix releases, and the dict-hash, which is only used
> by the dictionary implementation, and only if all keys to the dict are
> strings.

The distinction between secret (private, secure) and "public" hash
(deterministic) is not clear to me.

Example: collections.UserDict implements __hash__() using
hash(self.data). Should it use the public or the private hash?
collections.abc.Set computes its hash using hash(x) of each item. Same
question.

If we need to use the secret hash, it should be exposed in Python.
Which function/method would be used? I suppose that we cannot add
anything to stable releases like 2.7.

Victor