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,FREEMAIL_FROM autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,64afbf156d06bbe7 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-09-29 19:58:56 PST Path: news1.google.com!newsfeed.stanford.edu!bloom-beacon.mit.edu!nycmny1-snh1.gtei.net!washdc3-snh1.gtei.net!news.gtei.net!chcgil2-snh1.gtei.net!news.bbnplanet.com!wn11feed!worldnet.att.net!204.127.198.203!attbi_feed3!attbi.com!rwcrnsc54.POSTED!not-for-mail Message-ID: <3F78F159.9040800@comcast.net> From: "Robert I. Eachus" User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.0.2) Gecko/20021120 Netscape/7.01 X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: 'Valid, subtypes and constraint checking - Thanks References: <3F74E844.1020001@comcast.net> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit NNTP-Posting-Host: 24.34.139.183 X-Complaints-To: abuse@comcast.net X-Trace: rwcrnsc54 1064890735 24.34.139.183 (Tue, 30 Sep 2003 02:58:55 GMT) NNTP-Posting-Date: Tue, 30 Sep 2003 02:58:55 GMT Organization: Comcast Online Date: Tue, 30 Sep 2003 02:58:55 GMT Xref: news1.google.com comp.lang.ada:281 Date: 2003-09-30T02:58:55+00:00 List-Id: Peter Amey wrote: > Thanks to all the responders. The advice is consistent and useful. In > deference to Jean-Pierre, I withdraw the adjective "horrible" for the > use of unchecked conversion! The right name for Unchecked_Conversion is It_is_the_programmer's_job_to_do_some_checking_on_this_Conversion. But the apostrophe would have made it an attribute. ;-) Seriously the right place to use Unchecked_Conversion is when you, the programmer need to do some type checking, and nowhere else. For completeness, Unchecked_Deallocation should be Assume_that_there_are_no_other_valid_copies_of_this_access_value. In both cases, the compiler is not promising the user it won't do any checking, or will free the memory pointed to by the access value. The purpose of these units is to allow the programmer to assert something to the compiler. -- Robert I. Eachus "Quality is the Buddha. Quality is scientific reality. Quality is the goal of Art. It remains to work these concepts into a practical, down-to-earth context, and for this there is nothing more practical or down-to-earth than what I have been talking about all along...the repair of an old motorcycle." -- from Zen and the Art of Motorcycle Maintenance by Robert Pirsig