From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00
	autolearn=unavailable autolearn_force=no version=3.4.4
Path: 
 eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!feed.usenet.farm!feeder3.usenet.farm!newsfeed.xs4all.nl!newsfeed9.news.xs4all.nl!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail
From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Ada Annoyances
Date: Tue, 4 Jul 2017 22:52:57 +0300
Organization: Tidorum Ltd
Message-ID: <es2a0qFqlamU1@mid.individual.net>
References: <1ac5a44b-4423-443a-a7bb-2864d9abe78f@googlegroups.com>
 <d6b02354-93b5-4364-9fe5-3d22b47156e9@googlegroups.com>
 <be1619b4-2220-4287-8e67-1af32377d3f7@googlegroups.com>
 <oijkah$mnh$1@franka.jacob-sparre.dk>
 <4921bd4e-3827-a7ac-7f2d-d60edbc514a3@tidorum.invalid>
 <oiphqk$osf$1@franka.jacob-sparre.dk> <erd8jiFhsroU1@mid.individual.net>
 <oirvdf$t0$1@franka.jacob-sparre.dk> <erl137Fp39dU1@mid.individual.net>
 <wcca84q5vq1.fsf@TheWorld.com> <oj4784$kqb$1@franka.jacob-sparre.dk>
 <wccy3s51cic.fsf@TheWorld.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
X-Trace: individual.net XlRI9Sj/rwAhnzCpWCrS7gGjrtcc8cyGC/1BIWlLIOGVjLqse5
Cancel-Lock: sha1:DPNNQm9CIXXUKvc+1oMPKInTFf8=
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:45.0)
 Gecko/20100101 Thunderbird/45.8.0
In-Reply-To: <wccy3s51cic.fsf@TheWorld.com>
Xref: news.eternal-september.org comp.lang.ada:47288
Date: 2017-07-04T22:52:57+03:00
List-Id: <comp.lang.ada>

On 17-07-03 23:39 , Robert A Duff wrote:
> "Randy Brukardt" <randy@rrsoftware.com> writes:
>
>> "Robert A Duff" <bobduff@TheWorld.com> wrote in message
>> news:wcca84q5vq1.fsf@TheWorld.com...
>>> Niklas Holsti <niklas.holsti@tidorum.invalid> writes:
>> ...
>>> I agree, I don't see a problem here.  When Finalize is called, it
>>> dispatches via the currrent Tag.  Tags can't change in Ada, but if they
>>> could it would still dispatch via the Tag value present when Finalize is
>>> called.
>>
>> That's not the problem. The problem is knowing whether to call Finalize at
>> all. The only solution I could see for the GNAT approach is to treat all
>> tagged objects as controlled (using a null Finalize in cause the object
>> isn't controlled). That's expensive.
>
> In this fictional/future version of Ada, I presume the Tag of an object
> could only change if it's a class-wide object.

That was my intention, yes, apologies for not saying so, explicitly.

> So you don't have to
> finalize all tagged objects -- just class-wide ones,

    [snip]

> Actually, not even that.  Just every class-wide object that
> uses this new feature.  It would be known at the root of
> the type hierarchy whether Tags can change.  So there's no
> distributed overhead.

Good to hear. I will try to write up a 'Maximum_Size suggestion for 
ada-comment. May take a while, though.

-- 
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
       .      @       .