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,FREEMAIL_FROM autolearn=unavailable autolearn_force=no version=3.4.4 X-Received: by 10.66.237.100 with SMTP id vb4mr11354474pac.20.1466906558275; Sat, 25 Jun 2016 19:02:38 -0700 (PDT) X-Received: by 10.157.11.173 with SMTP id 42mr519901oth.10.1466906558230; Sat, 25 Jun 2016 19:02:38 -0700 (PDT) Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!mx02.eternal-september.org!feeder.eternal-september.org!news.glorb.com!jk6no2350678igb.0!news-out.google.com!i62ni5205ith.0!nntp.google.com!jk6no2350674igb.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Sat, 25 Jun 2016 19:02:37 -0700 (PDT) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=2601:191:8202:8510:5985:2c17:9409:aa9c; posting-account=fdRd8woAAADTIlxCu9FgvDrUK4wPzvy3 NNTP-Posting-Host: 2601:191:8202:8510:5985:2c17:9409:aa9c References: <58b78af5-28d8-4029-8804-598b2b63013c@googlegroups.com> User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: <3a978db3-e775-4e4a-acc0-8082f7376069@googlegroups.com> Subject: Re: RFC: Prototype for a user threading library in Ada From: rieachus@comcast.net Injection-Date: Sun, 26 Jun 2016 02:02:38 +0000 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Xref: news.eternal-september.org comp.lang.ada:30937 Date: 2016-06-25T19:02:37-07:00 List-Id: On Saturday, June 25, 2016 at 3:11:57 AM UTC-4, Dmitry A. Kazakov wrote: =20 > The problem at hand is that parallel asynchronous code cannot be=20 > designed in a reasonable way, at all. It is written it in a form of a=20 > state machine, logically and technically *gotos*. It is the state of=20 > software engineering of 70s wrapped in Ada constructs. Um, I've always thought it funny that Ada state machines and Ada tasking mi= x nicely, and both need to be at the library level to work efficiently. I a= lways used LALR on Multics which could handle LALR(k) grammars for any k, a= nd even some non-LR grammars. But it could also take a source file which m= ixed PL/I, C, Fortran, or Ada code with the grammar productions, and genera= te a (huge) source file which used a table driven engine. If, and I understand it is a big if you could map the input to one or more = independent sequential file, everything was wonderful. However if you want= ed to handle interacting inputs you were up a creek. This limitation is no= t as bad as it sounds. To take am aircraft radio, there would be several s= ubsystems that could be handled separately. The interrupt causing events (f= rom operator input) could be mixed into the data stream: operating_state := :=3D (receiver_input) | (transmission) |(interrupt) (operating_state); I can't imagine building a complex real-time system without a grammar tool = and Lui Sha & Goodenough real-time scheduling support tools.