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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Intervention needed?
Date: Fri, 29 Mar 2019 17:16:06 -0500
Organization: JSA Research & Innovation
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Xref: reader01.eternal-september.org comp.lang.ada:56008
Date: 2019-03-29T17:16:06-05:00
List-Id: <comp.lang.ada>

"Florian Weimer" <fw@deneb.enyo.de> wrote in message 
news:87wokhk289.fsf@mid.deneb.enyo.de...
>* Randy Brukardt:
>
>> It's also possible that Ada 2020 will have a form of pointer ownership.
>> (Unfortunately, we didn't make any conclusions on that during yesterday's
>> meeting, so it's still in limbo, and we're getting very close to the 
>> finish
>> line.)
>
> What about other holes in the type system?  Aliasing can occur in
> function calls even without pointers.

No one submitted any problems in that area (and I don't see why "aliasing" 
equates to "a hole in the type system" anyway).

Personally, I don't think it is possible to meet the goals for efficiency 
without aliasing -- one would have to eliminate things like by-reference 
parameter passing and techniques like lookup indexes to avoid aliasing. That 
sort of thing is pointless, at least when performance (time/space/power) 
matter.

One can always chose to use Ada in a functional manner (by requiring single 
assignment and the like), but I don't think that functional programming of 
that sort is practical for larger programs.

                                           Randy.