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,e64088334cf5790e X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2002-11-13 22:29:21 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!logbridge.uoregon.edu!kibo.news.demon.net!news.demon.co.uk!demon!not-for-mail From: Simon Wright Newsgroups: comp.lang.ada Subject: Re: Exchanging objects between programs with different inheritance hierarchies Date: 14 Nov 2002 06:29:23 +0000 Organization: Pushface Sender: simon@smaug.pushface.org Message-ID: References: NNTP-Posting-Host: pogner.demon.co.uk Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: news.demon.co.uk 1037255360 15068 62.49.19.209 (14 Nov 2002 06:29:20 GMT) X-Complaints-To: abuse@demon.net NNTP-Posting-Date: Thu, 14 Nov 2002 06:29:20 +0000 (UTC) User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.1 Xref: archiver1.google.com comp.lang.ada:30851 Date: 2002-11-14T06:29:23+00:00 List-Id: tmoran@acm.org writes: > > You almost never have to override 'Input, 'Output. 'Read and 'Write, > I think it's "almost always" rather than "almost never". If it's an > object of any complexity, in a program that's more than just quick > and dirty, you probably need to code your own routines to have > better control over just how things are laid out in the stream, and > how fast it runs. (The following is "as I understand it") 'Input, 'Output use bounds, discriminants or tags to control exactly what 'Read, 'Write routines get called. So you _must_ get 'Read, 'Write right. Of course I agree that you may need control over how bounds, discriminants or tags are written, in which case you'll need to specify 'Input, 'Output as well. But it's not a 'must'.