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,d402e2c741db0d0 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2004-01-08 17:28:18 PST Path: archiver1.google.com!postnews1.google.com!not-for-mail From: adam@irvine.com (Adam Beneschan) Newsgroups: comp.lang.ada Subject: Re: Language lawyer question: Equality on 'Access attributes Date: 8 Jan 2004 17:28:14 -0800 Organization: http://groups.google.com Message-ID: References: <4LKdnRRNyv6AlmCiRVn-ig@comcast.com> <6bSdnYBKy_diPGCi4p2dnA@gbronline.com> NNTP-Posting-Host: 66.126.103.122 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: posting.google.com 1073611698 14196 127.0.0.1 (9 Jan 2004 01:28:18 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Fri, 9 Jan 2004 01:28:18 +0000 (UTC) Xref: archiver1.google.com comp.lang.ada:4234 Date: 2004-01-08T17:28:14-08:00 List-Id: Ze Administrator wrote in message news:<6bSdnYBKy_diPGCi4p2dnA@gbronline.com>... > Robert A Duff wrote: > >>3.10.2(24), X'Access does *not* necessarily return any sort of type > >>implicitly defined by the language (for which no comparison operations > >>would be defined). The wording of this clause is: > >> > >> The type of X'Access is an access-to-object type, as determined by > >> the expected type. > >> > >>The way I read this is that the type of X'Access is the expected type, > >>which could be a program-defined type, which *would* have comparison > >>operations defined for it. > > I'd rather agree with Robert Eachus. If 'X' and 'Y' are > both Integers, then X'Access obviously has to be a named > or anonymous type that is an access Integer. Problem is, > there could be a dozen named types visible at that point > which are defined that way. Some of them could be limited. > You are asking the compiler to arbitrarily pick any visible > non-limited 'access Integer' type, and use it for the comparison. No, I'm not. If there are a dozen named access-to-integer types directly visible at that point (which would mean that their "=" operators are also visible), the RM rules clearly say that "=" would be ambiguous. I think I briefly touched on that situation in my original post. The question is, what should happen when only one such "=" operator is a possibility. -- Adam