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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: grassroots thoughts on access types
Date: Fri, 9 Feb 2018 18:01:38 +0100
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Xref: reader02.eternal-september.org comp.lang.ada:50340
Date: 2018-02-09T18:01:38+01:00
List-Id: <comp.lang.ada>

Others have responded to your questions. I'd like to mention my thoughts on 
using access-to-object types (which I'll call "access types") in general. (By 
"use", I'm referring to designing code with access types, not to using them when 
required to in order to reuse existing code. Gnoga, for example, requires you to 
supply some access values to use it.)

It's very rare to actually need to use access types in Ada. Other than while 
learning the language, it's quite likely that you'll never encounter a situation 
in which you'll need them. So while it's important to learn how they work, you 
shouldn't be designing in terms of them.

My personal rules for designing with access types:

1. Don't use access types
2. If you think you need access types, see rule 1.
3. If you still think you need access types, don't use visible or anonymous 
access types
4. If you think you need visible or anonymous access types, see rule 3.
5. If you still think you need visible or anonymous access types, then you 
shouldn't design software.

-- 
Jeff Carter
"Gentlemen, you can't fight in here. This is the War Room!"
Dr. Strangelove
30