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From: Duncan Sands <baldrick@free.fr>
Newsgroups: comp.lang.ada
Subject: Re: Hashing on System.Address
Date: Tue, 14 Jun 2005 09:27:33 +0200
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Date: 2005-06-14T09:27:33+02:00

> Good idea.  The other thing I haven't really figured out is what to do
> if you have a 64-bit address, and Hash_Type is only 32.  Ideally you'd
> like to compute a 32-bit hash value that uses all 64 bits of the
> address.

Yes, that's the problem.  In fact to be portable the code should work
regardless of which type has the bigger modulus.

> Alternatively, you could use the ordered container, since type
> System.Address has a less than ("<") relational operator.

I considered that, but since I'm sure to want to hash on addresses one
day, it seemed like a good idea to bite the bullet and come up with a
good solution now.

By the way, is there any reason why Ada.Containers doesn't provide some
standard hash functions?  I reckon hashing on strings and on addresses
would be pretty handy.

Ciao,

Duncan.