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-Thread: 103376,699cc914522aa7c4 X-Google-Attributes: gid103376,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news2.google.com!news4.google.com!news3.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local01.nntp.dca.giganews.com!nntp.megapath.net!news.megapath.net.POSTED!not-for-mail NNTP-Posting-Date: Tue, 16 Jan 2007 16:35:17 -0600 From: "Randy Brukardt" Newsgroups: comp.lang.ada References: <1168885771.30643.20.camel@localhost> <1168891576.30643.39.camel@localhost> <5NKdnTv2UZfVZTbYnZ2dnUVZ_vipnZ2d@megapath.net> Subject: Re: Structured exception information Date: Tue, 16 Jan 2007 16:36:13 -0600 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1807 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1807 Message-ID: NNTP-Posting-Host: 64.32.209.38 X-Trace: sv3-3V9GVPnL/d7A9h2NvCcaDfpLQvpLmypqVEvHjIJnbHGtGeCNHvRU6Udnq7dl327ARLHZix9DoC2vkqp!AhVP5u0pgQM5t+OpzscMKACtdJmWCAGawBVnYsvhcLKJFm/AfYlmqXP03zL9PE8tU9dqemqdniWS!t0LkdLSDUnElRw== X-Complaints-To: abuse@megapath.net X-DMCA-Complaints-To: abuse@megapath.net X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.32 Xref: g2news2.google.com comp.lang.ada:8203 Date: 2007-01-16T16:36:13-06:00 List-Id: "Robert A Duff" wrote in message news:wcc64b7or96.fsf@shell01.TheWorld.com... > "Randy Brukardt" writes: > > > We did look at this issue when working on the Amendment. The "obvious" > > answers seem to have issues with visibility and compatibility with existing > > Ada.Exceptions mechanisms. > > If we had done it right in Ada 95, we wouldn't have had the > Ada.Exceptions kludge in the first place, so no need to be complatible > with it. Well, don't look at me on that one... ;-) > I don't know what the visibility issues were, so I can't comment on > that. Do you happen to know which AI this was? Not off-hand, but it only takes a minute to look up... It was AI-264, "Exceptions as types". The title alone suggests trouble: the main issue is to provide type-safe data along with exceptions. The minor issue is a better way to deal with sets of exceptions. Neither of those necessarily require making exceptions into types. My personal feeling is that we solved a lot of the problems that we had with the exception proposal when we dealt with all of the issues that nested tagged types brought up. When we considered AI-264, we hadn't yet gone through that exercise, and the entire thing looked impossible. Having solved some of the related issues, it would be easier to deal with now. It would be even easier if we had a mechanism for user-defined 'Image (which would allow automatic converting to strings to keep the existing Ada.Exceptions routines working). Randy.