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=-1.8 required=3.0 tests=BAYES_00,PLING_QUERY autolearn=no 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: 2dsa | !2dsa ? Date: Wed, 23 Dec 2020 09:44:26 +0100 Organization: Aioe.org NNTP Server Message-ID: References: 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/78.6.0 X-Notice: Filtered by postfilter v. 0.9.2 Content-Language: en-US Xref: reader02.eternal-september.org comp.lang.ada:60934 List-Id: On 2020-12-23 02:32, Randy Brukardt wrote: > "Rod Kay" wrote in message > news:d3f3b7fb-e051-428b-a947-32310a64933en@googlegroups.com... >> Hello all, >> >> I've heard that the Distributed Systems Annex (DSA) may be dropped from >> the Ada standard soon. Can anyone confirm this ? > > Annex E remains in the proposed Ada 202x standard. > > Compiler support, of course, is up to vendors. Dunno if anyone is still > supporting it. It should be moved to the user level. As specified in the Annex there seems no obvious way to provide a user-defined transport for DSA, and there seems no way to have different implementations of DSA in the same program. >> I've been using the Polyorb implementation of DSA for some time and >> find >> it very useful. The way in which it abstracts away socket 'plumbing' >> details makes >> for very simple/understandable comms. Yes, but too simple to be universally useful. > That was the promise, not sure it ever really was realized. Since the Annex > was weakened enough that third-party support isn't really possible anymore > (necessary to allow it to be used with current middleware), it's really a > vendor-specific thing these days. Yes, I always wished to include DSA support based on various communication protocols I have implemented in Ada, rather than plain sockets. E.g. I have a ready-to-go DSA implementation for interprocess communication over shared memory, but no idea how to make GNAT aware of it. Or AQMP and ASN.1 look like a straightforward candidate as a DSA transport as they have detailed type description systems to map Ada objects. -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de