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, MSGID_RANDY autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,820de86ed0dafb8a X-Google-Attributes: gid103376,public From: Robert Dewar Subject: Re: Help Me Please :) Date: 2000/03/04 Message-ID: <89rqgp$nmb$1@nnrp1.deja.com>#1/1 X-Deja-AN: 593166288 References: <38BC4EAF.209AE20C@port.ac.uk> <89i6bi$u4p$1@nnrp1.deja.com> <2000Mar3.183321.69279@ludens> X-Http-Proxy: 1.0 x26.deja.com:80 (Squid/1.1.22) for client 205.232.38.14 Organization: Deja.com - Before you buy. X-Article-Creation-Date: Sat Mar 04 20:09:00 2000 GMT X-MyDeja-Info: XMYDJUIDrobert_dewar Newsgroups: comp.lang.ada X-Http-User-Agent: Mozilla/4.61 [en] (OS/2; I) Date: 2000-03-04T00:00:00+00:00 List-Id: In article <2000Mar3.183321.69279@ludens>, gazso@ludens.elte.hu (Erdelyi Gaspar) wrote: > I think that GNAT is not comparable to DEC Ada (for OpenVMS) > which provides very useful error messages. DEC Ada is Ada83 > only and the prices are not comoparable, too... Well the prices are not that far from comparable, but that's another issue anyway. With regard to error messages there are four cases of interest: 1. Cases where DEC Ada 83 simply gets confused, and GNAT does not. There are quite a few of these, one notable example is the GNAT circuit for dealing with the semicolon/IS confusion. All other compilers I know can get confused by this, including DEC Ada 83. 2. Cases where GNAT gets confused, and DEC Ada 83 does not. I don't currently know of any such cases, but that does not mean they do not exist. If you know of such cases, it is always useful to submit them to report@gnat.com, we are always working to tune the error message circuit (indeed giving good messages is a hobby of mine :-) 3. Cases where neither compiler gets confused and the error messages are comparable. Having worked through the entire DEC test suite, which contains thousands of examples of error situations, I would say this is probably the most common case. 4. Cases where neither compiler gets confused and the error messages are substantially different. These are interesting cases to look at. Sometimes there is simply a difference in style. GNAT aims at trying to keep error messages short and informative, whereas DEC Ada 83 often gives rather voluminous messages. In GNAT, you can more nearly approximate this verbose mode by using the -gnatf switch. But there will still be differences, some of these might just be a matter of taste, some may be cases where real improvements are possible (there are certainly cases in the DEC test suite where the GNAT message is more useful, I don't know of any cases left where I consider the DEC Ada 83 message significantly better in this test suite, because we used the suite to tune up such cases in GNAT :-) Here again, in case 4, it is very useful if you send in cases where you think an error message can be improved. This actually is a much more general request than just comparing these two compilers. Any time you get a compile time message that you think could be clearer, send it along. We may well agree, and we may well be able to do something about it. Robert Dewar Ada Core Technologies Sent via Deja.com http://www.deja.com/ Before you buy.