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=-1.2 required=5.0 tests=BAYES_00,FREEMAIL_FROM, FROM_STARTS_WITH_NUMS autolearn=no autolearn_force=no version=3.4.4 X-Received: by 10.36.112.2 with SMTP id f2mr7683167itc.36.1512386241091; Mon, 04 Dec 2017 03:17:21 -0800 (PST) X-Received: by 10.157.11.207 with SMTP id 73mr643931oth.2.1512386240856; Mon, 04 Dec 2017 03:17:20 -0800 (PST) Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!feeder.eternal-september.org!news.kjsl.com!usenet.stanford.edu!i6no2663953itb.0!news-out.google.com!s63ni3284itb.0!nntp.google.com!i6no2663945itb.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Mon, 4 Dec 2017 03:17:20 -0800 (PST) Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=85.242.253.113; posting-account=rhqvKAoAAABpikMmPHJSZh4400BboHwT NNTP-Posting-Host: 85.242.253.113 User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: Subject: Exception_Occurence and language designers From: Mehdi Saada <00120260a@gmail.com> Injection-Date: Mon, 04 Dec 2017 11:17:21 +0000 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Xref: reader02.eternal-september.org comp.lang.ada:49343 Date: 2017-12-04T03:17:20-08:00 List-Id: Curiously I find very interesting details of the norm, the inner working. M= aybe I have a vocation of language lawyer ? This time it's about exceptions. Why have created both Exception_Identity and Exception_Occurence, often for= the same subprograms ? Especially, about Exception_Occurence: Was it that the designers wanted to maintain compatibility, rather than bre= aking the last system and implementing something syntaxically closer to "su= btype/type File_Not_found is Exception/new Exception; Not_Found_Error: File= _Not_Found", a system closer to the type/subtype/instance model, but for ex= ceptions ? Has it been thought about at one time ? To me it seems the Excep= tion_Occurence'name declaration below, looks a lot like an object declarati= on, the exception Fine_Not_Found being a type. Not the first case I thought it could be nicer to syntaxic constructs, rath= er than relying on predefined libraries (as with "controlled") ? when Not_Found_Error : File_Not_Found =3D> Text_IO.Put_Line(Exceptions= .Exception_Message(Not_Found_Error));