[Python-Dev] Hashable memoryviews

Stefan Krah stefan at bytereef.org
Sun Nov 13 13:05:24 CET 2011

Nick Coghlan <ncoghlan at gmail.com> wrote:
> > With slices or the new casts (See: http://bugs.python.org/issue5231,
> > implemented in http://hg.python.org/features/pep-3118#memoryview ),
> > it is possible to have different hashes for equal objects:
> Note that Antoine isn't suggesting that the underlying hash be *used*
> as the memoryview's hash (that would be calculated according to the
> same rules as the equality comparison). Instead, the ability to hash
> the underlying object would just gate whether or not you could hash
> the memoryview at all.

I think they necessarily have to use the same hash, since:

exporter = m1 ==> hash(exporter) = hash(m1)
m1 = m2 ==> hash(m1) = hash(m2)

Am I missing something?

Stefan Krah

More information about the Python-Dev mailing list