Re: Recursion limit problems

On May 14, 1:20 pm, "Terry Reedy" <tjre...@xxxxxxxx> wrote:

Dicts first compare hashes and if they are equal, then check equality. If
two unequal strings have the same hash value, as is possible of course
(given only 2**32 possible hashes and many more possible strings), both can
still be used as different keys. Ditto for unequal numbers. Or for a
number and string with equal hashes. And so on. The first quoted
sentence, about mixing, is directed at minimizing such hash collisions.

Now my question is, since the definition mentions __cmp__ explicity.
Is that the only function it uses? What if __ne__, __eq__ are defined,
but not __cmp__?

Finally I am still confused about the inequality. Does dict only care
about the __cmp__ ouput being 0 and ignore the rest, or does it make
use of -1,1 as well? Could I just say that 0 defines equality in my
object and 1 otherwise, without regard of it being less than or
greater than?

Thanks!

.

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