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=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,573be8c453ecbff4 X-Google-Attributes: gid103376,public From: "Pat Rogers" Subject: Re: 'Read for pointers Date: 2000/07/26 Message-ID: #1/1 X-Deja-AN: 651187953 References: X-Priority: 3 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2919.6600 X-Complaints-To: abuseswbell.net X-Trace: nnrp3.sbc.net 964653904 208.191.184.67 (Wed, 26 Jul 2000 18:25:04 CDT) Organization: SBC Internet Services X-MSMail-Priority: Normal NNTP-Posting-Date: Wed, 26 Jul 2000 18:25:04 CDT Newsgroups: comp.lang.ada Date: 2000-07-26T00:00:00+00:00 List-Id: wrote in message news:YEJf5.49$LV1.69164@news.pacbell.net... > >Further to my previous post, to the effect that one can indeed read > >mode out parameters: the access value of the actual is copied into the > >formal, so you get a meaningful value coming in even though the mode > >is out. See RM 6.4.1{12,13} > So to catch bugs at an early time, given > type Handle_Type is access ... > procedure p(x : some_stuff; Handle : out Handle_Type); > one should > Handle := null; > p(y, Handle); > otherwise a supposedly new object at Handle.all may actually be > an old object. That must be fun to debug. I'm not sure I see your point, given the context. The variable Handle, used as the actual to the call to P, would initially have the null value (absent any explicit initialization) automatically. So the value copied in is still meaningful, even if never assigned prior to the call. -- Pat Rogers Consulting and Training in: http://www.classwide.com Deadline Schedulability Analysis progers@classwide.com Software Fault Tolerance (281)648-3165 Real-Time/OO Languages Adam ... does not deserve all the credit; much is due to Eve, the first woman, and Satan, the first consultant. Mark Twain