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 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,616091a85ff150f1 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-12-06 01:41:06 PST Path: archiver1.google.com!postnews1.google.com!not-for-mail From: rod@praxis-cs.co.uk (Rod Chapman) Newsgroups: comp.lang.ada Subject: Re: Ada 200X Assertions Date: 6 Dec 2001 01:41:06 -0800 Organization: http://groups.google.com/ Message-ID: References: <3C0C48BE.3B20F04E@adaworks.com> <9uj730$shr$1@news.online-isp.com> <9ujf1c$hhr$1@news.huji.ac.il> <3C0EEC25.E2738366@adaworks.com> NNTP-Posting-Host: 213.155.153.242 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: posting.google.com 1007631666 901 127.0.0.1 (6 Dec 2001 09:41:06 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: 6 Dec 2001 09:41:06 GMT Xref: archiver1.google.com comp.lang.ada:17500 Date: 2001-12-06T09:41:06+00:00 List-Id: Richard Riehle wrote in message news:<3C0EEC25.E2738366@adaworks.com>... > It sounds as if Dr. Lamm is > taking on the job of seeking solutions for DBC within Ada. Kudos to him. I hope any such effort starts with a good look at how SPARK works, where support for DBC is very strong. Even without explicit pre- or post-conditions, a simple subprogram declaration in SPARK carries a far more onerous contract than the same piece of text in Ada. One critical issue is visibility - most non-trivial assertions involve states which aren't visible according to Ada's rules, so we have to have the "--# global" annotation to extend visibilty of state in annotation context. The design of a useful assertion mechanism in Ada0Y or later would have to consider this need carefully. - Rod