[Python-Dev] returning longs from __hash__()
arigo at tunes.org
Tue Aug 8 12:26:08 CEST 2006
The 2.5 change of id() to return positive ints-or-longs is likely to
cause quite some breakage in user programs that erroneously implemented
custom __hash__() functions returning a value based on an id(). This
was discussed a few times already but it showed up again as a bug report
(#1536021). Of course it has always been documented that id() is not
directly suitable as the return value of a custom __hash__(), but so far
it worked on 32-bit machines so people have been doing it all the time.
Maybe the user should just be able to return any integer value from a
custom __hash__() without having to worry about not exceeding
After all the returned value has no real meaning. If a long is returned
we could take its hash again, and use that number internally.
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