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Re: Ann: SWI-Prolog 5.6.54

by Jan Wielemaker :: Rate this Message:

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On Thursday 17 April 2008 02:48:24 Richard A. O'Keefe wrote:

> Concerning the hashing of integers,
> There is a great new book by Andres Valloud,
> called "Hashing in Smalltalk: Theory and Practice."
>
> Anyone concerned with hashing should read this book.
> Its relevance here is that there are excellent reasons
> for letting the hash of fixnums be themselves.
>
> Someone, was it Jan, said:
> >> I think the new implementation is better as it guarantees proper
> >> distribution when hashing integers that have some pattern.
>
> It can't.  No hashing method can possibly do that.

I guess `guarantees' is a bit too strong. Using a cryptographic hash in
the bits of the integer however would come very close to a `guarantee'.

        Cheers --- Jan

P.s. I'd suspect you to have an opinion on hash_term <-> term_hash ...


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