ben.tay...@email.com writes: > 1. Is it correct that if you hash two things that are not equal they > might give you the same hash value?
Yes, hashes are 32 bit numbers and there are far more than 2**32 possible Python values (think of long ints), so obviously there must be multiple values that hash to the same slot. > 2. Should the hash of None vary per-machine? If the docs say this shouldn't happen, then it's a bug. Otherwise, it should probably be considered ok. > 3. Given that presumably not all things can be hashed (since the > documentation description of hash() says it gives you the hash of the > object "if it can be hashed"), should None be hashable? Yes, anything that can be used as a dict key (basically all immutable values with equality comparison) should be hashable. -- http://mail.python.org/mailman/listinfo/python-list
