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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: prohibit certain generic instantiations in Ada 2005
Newsgroups: comp.lang.ada
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Date: Sat, 11 Feb 2006 11:45:32 +0100
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Date: 2006-02-11T11:45:22+01:00
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On Fri, 10 Feb 2006 20:03:25 +0100, Georg Bauhaus wrote:

> On Fri, 2006-02-10 at 19:25 +0100, Dmitry A. Kazakov wrote:
> 
>> So,
>> basically, C++ is unable to check anything specific about the type of
>> template a parameter.
> 
> Don't you think that while template <class T> doesn't
> require T to conform to some type, T's operations can
> still be named in the template definition? Like with
> the Can_Copy example that Stroustrup explains?

Things from the definition are checked upon instantiation = too late.
Talking about compile-time checks, we should separate compilation of
templates and their instantiations. In my view, anything checked outside
the formal part does not count, because it is *other* compile-time.

[ Let you use a code management system and a template library is under that
system. Then each time you ship a new version of the library, all the
projects dependant on it should get a new version as well. Now, because
templates aren't properly checked, you can't much rely on them until you
try. In the end, you have an immense overhead in the developing cycle.]

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de