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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: little precision about anonymous access types
Date: Wed, 21 Mar 2018 17:46:06 -0500
Organization: JSA Research & Innovation
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Xref: reader02.eternal-september.org comp.lang.ada:51118
Date: 2018-03-21T17:46:06-05:00
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"Mehdi Saada" <00120260a@gmail.com> wrote in message 
news:42387d28-c983-4e58-9522-815ccd1ad0fb@googlegroups.com...
> It sounds interesting. Could you explain a bit more what effect you refer 
> to ? Some code to show it ? Or a link to it.
> For the time being, the few things I know is that anonymous types are 
> useful and safe for : coextensions, and controlling access 
> parameters/results and the dispatching they allow.
> So if you allude to dispatching, I might understand your point (a bit), 
> otherwise I don't.

Yikes. Anonymous access type act differently than their named counterparts 
in the following cases (to name a few):
    (1) Hard to set the convention, pre/postconditions, other aspects 
(because there's no declaration);
    (2) Accessibility for anonymous access parameters (both objects and 
subprograms), discriminants, stand-alone objects;
    (3) Full context passed with anonymous access-to-subprogram parameters;
    (4) Dynamic accessibility causes a "tripping hazard" (Program_Error with 
some actual parameters) - access parameters, stand-alone objects.
    (5) Hidden null exclusion for controlling anonymous access parameters.

               Randy.