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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Unchecked_Deallocation with tagged types
Date: Sun, 18 Apr 2021 18:08:44 +0200
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On 4/18/21 12:20 PM, J-P. Rosen wrote:
>>
>> For every access variable P, there could exist the attribute procedure
>>
>>    P'Free;
>>
> Which would defeat the goal of Unchecked_Deallocation.
> 
> Ada (or more precisely Ichbiah) chose to deallocate through an instantiation of 
> a generic for good reason. Deallocation is a place where many problems can come 
> from, it is important to be able to trace where they are. The current solution 
> forces you to put "with Unchecked_Deallocation" on top of every module that 
> deallocates, therefore telling the reader that there is some danger in it, and 
> making it easier to find where all the deallocations happen.

Since all Ada developers only use access types when necessary (0.1% of programs) 
and always hide them in packages, this is less of an issue.

In the ideal world.

-- 
Jeff Carter
"Run away! Run away!"
Monty Python and the Holy Grail
58