From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.5-pre1 (2020-06-20) on ip-172-31-74-118.ec2.internal X-Spam-Level: X-Spam-Status: No, score=-1.9 required=3.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.5-pre1 Path: eternal-september.org!reader02.eternal-september.org!aioe.org!5WHqCw2XxjHb2npjM9GYbw.user.gioia.aioe.org.POSTED!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: Unchecked_Deallocation with tagged types Date: Wed, 21 Apr 2021 12:11:07 +0200 Organization: Aioe.org NNTP Server Message-ID: References: <607b56f8$0$3721$426a34cc@news.free.fr> <07863309-4541-4497-8cec-d88179e634bdn@googlegroups.com> <3d6e49b6-f195-4dc2-bf4b-795f18f2da9dn@googlegroups.com> NNTP-Posting-Host: 5WHqCw2XxjHb2npjM9GYbw.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.9.1 X-Notice: Filtered by postfilter v. 0.9.2 Content-Language: en-US Xref: reader02.eternal-september.org comp.lang.ada:61881 List-Id: On 2021-04-21 10:35, Jeffrey R. Carter wrote: > On 4/20/21 11:10 PM, Niklas Holsti wrote: >> On 2021-04-20 23:32, Jeffrey R. Carter wrote: >>> On 4/20/21 8:53 PM, Randy Brukardt wrote: >>>> >>>> 'Free makes more sense in a new language (an Ada follow-on). >>> >>> Right. I don't think it would be a good idea to add it to Ada. >>> >>> But I think a new language should not have pointers at all. >>> >>> No more radical than not having arrays. >> >> >> It seems to me that a language without arrays and pointers would be >> very difficult to use in an embedded, real-time, close-to-HW context. >> So we would lose the nice wide-spectrum nature of Ada. > > I don't see that pointers are needed for such S/W. Try to load and bind a relocatable library without pointers. > Brukardt has recently been discussing the idea that a high-level > language such as Ada should not have arrays, which is why I referenced > it. Such a language might not be convenient for such systems. > > But the idea is that arrays are a low-level implementation feature that > are usually used to implement higher-level abstractions, such as > sequences and maps. A language without arrays would have direct support > for such abstractions. That is not enough, even if providing such abstractions were viable. Which is not, because they would be far more complex than array abstraction and resolve none of the problems array abstraction has. E.g. container subtypes constrained to subtypes of elements and/or subtypes of keys. Array is a simplest case of container. If you cannot handle arrays, how do you hope to handle maps? Then see above, and explain how an opaque map will deal with a shared memory mapped into the process address space? Or what would be the primitive operation Write of Root_Stream_Type? -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de