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,e61c8636ef35379d X-Google-Attributes: gid103376,public From: "Randy Brukardt" Subject: Re: Ada Streams usage (was Escape Sequences in Strings) Date: 2000/11/21 Message-ID: #1/1 X-Deja-AN: 696351254 References: <3A17B0E2@MailAndNews.com> <3A129A89.1B69E2FE@acm.org> <3A13D59E.63A6F92@earthlink.net> <3A168546.89CA38F7@acm.org> <3A177878.AD747325@telepath.com> <3A182633.BDE82EA9@acm.org> <8v9lip$2dr$1@nnrp1.deja.com> <8ves0e$a0m$1@nnrp1.deja.com> X-MimeOLE: Produced By Microsoft MimeOLE V4.72.3719.2500 X-Complaints-To: abuse@alpha.net X-Trace: homer.alpha.net 974846947 156.46.62.124 (Tue, 21 Nov 2000 16:49:07 CST) NNTP-Posting-Date: Tue, 21 Nov 2000 16:49:07 CST Newsgroups: comp.lang.ada Date: 2000-11-21T00:00:00+00:00 List-Id: Ted Dennison wrote in message <8ves0e$a0m$1@nnrp1.deja.com>... >In article , > "Randy Brukardt" wrote: >> (Importantly, the base type problem means that streams may not be >> portable between different Ada compilers on the same machine. Even if >> GNAT is following the AI proposal, there is no requirement that other >> compilers do so until the AI is completed.... Caveat empor.) > >That *still* won't make streams compatable between diferent compilers >though, will it? Isn't the representation of a tagged type's tag on >'output implementation defined? You can of course specify it. But you'd >have to know ahead of time that you want to use streams portably with >your objects, then go in and specify the external tag for every object. Yes, for tagged types, you have to specify the external tag for every tagged type. I doubt anything will change there soon (could be wrong, though). I was thinking more about reading an untagged object from a stream. We ran into this problem trying to read Windows bitmaps from a stream (given that it is hetrogeneous, we pretty much have to use streams to do it); this isn't a tagged type (we do put the data into a tagged object after reading it, but it isn't read as one). We had quite a time getting all of the supported compilers to do it right. Randy Brukardt.