bugs? hash and the debugger.
ohshima at is.titech.ac.jp
ohshima at is.titech.ac.jp
Mon Dec 13 11:35:22 UTC 1999
Hi,
> Hash should be a fast function, since it is often used for
> quick rejection of potentially long comparisons. How about
> making the default collection hash be order independent, so
> there's no need to sort as part of hashing, and perhaps fall
> back to a simple function of size if it is greater than,
> say, 10.
Yes. Simply xor'ing the elements' hash values seems
better.
At first, I thought the hash values of Sets should be
distributed widely even if the elements of the Sets are
similar. But it doesn't have to.
> hash
> | hash |
> hash := self species hash.
> self size > 10 ifTrue: [^ hash + size].
> self do: [:elem | hash := hash bitXor: elem hash].
> ^ hash.
>
> Would this answer your needs?
Precisely speaking, this is not my needs:-) but it seems
reasonable implementation.
Thank you.
-- Yoshiki
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