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: ff6c8,b7857cb3cbabcf8d X-Google-Attributes: gidff6c8,public X-Google-Thread: f43e6,b7857cb3cbabcf8d X-Google-Attributes: gidf43e6,public X-Google-Thread: 103376,b7857cb3cbabcf8d X-Google-Attributes: gid103376,public X-Google-Thread: 10db24,b7857cb3cbabcf8d X-Google-Attributes: gid10db24,public X-Google-Thread: 1108a1,b7857cb3cbabcf8d X-Google-Attributes: gid1108a1,public From: dewar@merv.cs.nyu.edu (Robert Dewar) Subject: Re: Ada News Brief Date: 1996/10/27 Message-ID: #1/1 X-Deja-AN: 192495143 references: <533utt$43p@ns1.sw-eng.falls-church.va.us> <1996Oct15.160047.1@eisner> <32716EA6.4B35@thomsoft.com> organization: New York University newsgroups: comp.lang.ada,comp.sw.components,comp.object,comp.software-eng,comp.edu Date: 1996-10-27T00:00:00+00:00 List-Id: Dave Wood said "Er, well, rest assured that 'the company' made no such claim. The actual press release contained some suitable adjective, like "virtually", which somehow was dropped by the press. But hey, if they're going to screw up our press releases, I'm glad it's in our favor. (At least they didn't say: ObjectAda includes the full Ada 95 core language and will compile no Ada 83 code without changes...) " Well I am not sure this is in your favor. I think it is important to educate people away from the expectation that an Ada 83 switch will work perfectly on their Ada 83 code. There are two reasons. 1. The switch from an Ada 83 to an Ada 95 compiler may involve changes in implementatoin dependent choices (e.g. the behavior of representation pragmas). This is especially likely to be so if you are switching front ends (VADS to GNAT, or DEC to Rational, or Alsys to TSP). 2. There are subtle changes in semantics, e.g. of overloading, which are unlikely to be copied exactly. It makes no sense to have two overloading algorityhms, where the only function of one of them is to implement obscure Ada 83 rules that have been judged (a) undesriable and (b) too obscure to worry about compatibility issues. In addition, usually it is only worth trying to worry about correct Ada 83 rules, there seems little point (and it would be tough) to diagnose all possible Ada 83 semantic errors. One interesting criterion would be to see if a compiler can 100% validate against 1.11 with its Ada 83 switch. GNAT certainly makes no such claim. it is certainly true that advertisers and press are likely to be over enthusiastic in their claims here (I have seem literature from more than one vendor mislead on this point, not so much deliberately, but simply as the result of abbreviation, advertising often gives false impressions by not being able to give details).