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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 09:18:31 +0200
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Date: 2005-06-14T09:18:31+02:00

Hi Matthew,

> Use System.Storage_Elements.To_Integer to convert the address to an
> Integer_Address, and then convert that to type Hash_Type.

that's what I'm doing.  But there's no guarantee that they have the
same size, so it's not portable.  It's easy enough to thunk Integer_Address
to a modular type (which I'll also call Integer_Address here).  If
Integer_Address is smaller than or equal to Hash_Type then there's no
problem.  If it's larger then you can do some bit rotation, but it's surprisingly
awkward to do when you don't know the sizes in advance.  I was hoping
someone knew how to do this in a clean way.

All the best,

Duncan.