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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Anonymous access types are evil, why?
Date: Wed, 28 Aug 2013 16:10:13 -0500
Organization: Jacob Sparre Andersen Research & Innovation
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Date: 2013-08-28T16:10:13-05:00
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"Adam Beneschan" <adambeneschan@aol.com> wrote in message 
news:66f24ada-122c-4c01-9f04-5bc92233a456@googlegroups.com...
...
>> 2. Avoid anonymous access types. Prefer named access types and 
>> 'Unchecked_Access.
>
>I hope we don't have to draw this conclusion.  It would be sad if, with our 
>right hand,
>we're urging people to adopt Ada because of its safety, and then with our 
>left hand
>we recommend that they use 'Unchecked_Access and defeat the safety 
>mechanism.

Not sure why preferring named access types would imply anything about 
'Access or 'Unchecked_Access. If you're using either of those, you almost 
never have a choice - you almost always have to use 'Unchecked_Access. But 
you shouldn't have to use either, as Ada allows explicit conversion of 
structurally similar access types. You need named types in order to use 
structural conversion, of course.

Certainly "avoid anonymous access types" is good advice, not the least of 
which that they usually imply run-time accessibility checking overhead, 
which is never needed for named access types.

                          Randy.