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Newsgroups: comp.lang.ada
Date: Sat, 31 Aug 2013 08:57:32 -0700 (PDT)
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Subject: Re: Hash Type Size
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Xref: news.eternal-september.org comp.lang.ada:17068
Date: 2013-08-31T08:57:32-07:00
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To be honest, this was mostly just laziness on my part; there is no good (r=
ead: easy) way to hash an opaque data type, and so a quick and dirty (and a=
dmittedly non-ideal) way to simply use the pointer as the key itself.  But =
this is a lot tougher to rationalize now that they are different sizes, so =
I guess the real question is "what's a good way to hash a private type/acce=
ss value/system.address?"

It would be nice if there was a interface exclusively for doing this; somet=
hing like an 'Hash attribute that could be applied to any type to return ei=
ther a implementation-provided hash (like for strings) or that could be ove=
rridden by a programmer in fancier cases.  You can already sort of hack it =
together now using Ada.Strings.Hash(T'Image(o)).