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 X-Google-Thread: 103376,98c463a9e98cfdf5 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2002-06-13 07:45:08 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!news.he.net!cyclone-sf.pbi.net!151.164.30.35!cyclone.swbell.net!bos-service1.ext.raytheon.com!dfw-service2.ext.raytheon.com.POSTED!not-for-mail Message-ID: <3D08ABBA.C8AF105@raytheon.com> From: Mark Johnson X-Mailer: Mozilla 4.76 [en] (Windows NT 5.0; U) X-Accept-Language: en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: Ada exceptions. unchecked? References: <8db3d6c8.0206112300.3965a62b@posting.google.com> <3D0750F1.7A12342@raytheon.com> Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Date: Thu, 13 Jun 2002 09:27:06 -0500 NNTP-Posting-Host: 192.27.48.39 X-Complaints-To: news@ext.ray.com X-Trace: dfw-service2.ext.raytheon.com 1023978445 192.27.48.39 (Thu, 13 Jun 2002 09:27:25 CDT) NNTP-Posting-Date: Thu, 13 Jun 2002 09:27:25 CDT Organization: Raytheon Company Xref: archiver1.google.com comp.lang.ada:25871 Date: 2002-06-13T09:27:06-05:00 List-Id: Gisle S�lensminde wrote: > In article <3D0750F1.7A12342@raytheon.com>, Mark Johnson wrote: > [snip - explanation of java exceptions...] > > Adding it to Ada at this point would break a lot of code (but also > > likely FIX a lot of code when implemented). > > --Mark > > Checked exceptions as in Java is in fact a horrible idea. If you assume > that the program is designed with error handling in mind from the start, > it could work, but in practice you will discover at some point that some > lowlevel error condition the highlevel need to handle. In that case > all the methods in the entire call tree need to be changed. If the > application is sufficiently large, you simply can't do that. > I am not so certain if the problem is... - the implementation of checked exceptions in Java is broke - the constraints on implementing code that uses checked exceptions are too onerous or something else entirely. The point you make addresses a typical application problem. You have a higher level module attempting to recover from some low level implementation detail that should be transparent to it. I can argue that the one of the abstractions used to build the application is broken - not checked exceptions. Checked exceptions helped you find out that the design or implementation is broke - fix it. If THAT was the only problem with checked exceptions in Java, then I would argue that the addition of checked exceptions to Ada would be a good idea. However, I am not convinced of that at this time. --Mark