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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Why does Ada.Iterator_Interfaces specify Next as a function
 rather than a procedure?
Date: Thu, 7 Sep 2017 18:17:54 -0500
Organization: JSA Research & Innovation
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Xref: news.eternal-september.org comp.lang.ada:47977
Date: 2017-09-07T18:17:54-05:00
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<briot.emmanuel@gmail.com> wrote in message 
news:806ff091-efd2-4625-afec-c7a6dc7886a8@googlegroups.com...
>In my experience, a simpler approach is to use GNAT's Iterable aspect, 
>which
>is way simpler and more logical (really just a thin layer about the usual
>Cursor/Has_Element/Next/... operations).

If he's trying to create portable Ada code, that's hardly an option. Perhaps 
Ada 202x will include an easier solution to the problem.

I tend to agree that the use of interfaces here was a mistake; we ended up 
needing a bunch of aspects to make the solution usable, and at that point we 
should have just abandoned the interfaces and just used aspects. (This is 
one of my reasons for saying that interfaces themselves are pointless.) In 
any case, though, portable Ada code is stuck with them.

                                     Randy.