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: 103376,67ca96c42837a9ca X-Google-Attributes: gid103376,public From: dewar@gnat.com Subject: Re: Getting GNAT to issue ARM error messages Date: 1999/02/12 Message-ID: <7a1a9i$2kq$1@nnrp1.dejanews.com>#1/1 X-Deja-AN: 443593924 References: <79oj1f$e8p$1@nnrp1.dejanews.com> <1999Feb10.073547.1@eisner> X-Http-Proxy: 1.0 x10.dejanews.com:80 (Squid/1.1.22) for client 129.37.71.50 Organization: Deja News - The Leader in Internet Discussion X-Article-Creation-Date: Fri Feb 12 13:28:28 1999 GMT Newsgroups: comp.lang.ada X-Http-User-Agent: Mozilla/4.04 [en] (OS/2; I) Date: 1999-02-12T00:00:00+00:00 List-Id: In article <1999Feb10.073547.1@eisner>, Kilgallen@eisner.decus.org.nospam wrote: > A compiler referring a > newcomer to a page in the Ada95 reference manual could > lead to confusion because of the way that book is > written. And just to clarify what Larry wrote above, this is not in any way a criticism of the ADa 95 RM, just a comment on its different stylistic approach. Clarity for non-experts and precision for experts are often opposing goals. There are several factors in this opposition: 1. Precision for experts usually requires a more formal style that is less accessible for non-experts. 2. Precision requires considering marginal cases carefully and thoroughly that may confuse non-experts. 3. Redundancy, that is so often helpful in explaining things to non-experts, is a menace in a precise definition, it can only lead to self-contradiction, and adds nothing. 4. In a formal definition, precise terminology, and the style of depending on that terminology is an important tool, but it can often confuse (an example: how many non-expert users immediately understand that a generic package is not a package, so a rule that applies to packages does not [necessarily] apply to generic packages). The viewpoint of the designers of Ada 95 was that the Ada 83 reference manual was insufficiently precise, and that a more formal, more precise approach was desirable. This was a controversial point, and remains moot (undecided and arguable) in my opinion, but that's a separate issue from the current one (whether to put RM references in messages). One thing to remember here is that I was the one who started the idea of putting RM references in messages. The first compiler to do this was Ada/Ed, and at the time it was an innovation. I am not aware of previous compilers for other languages that contained references to the standard in this manner (after all most programmers for other languages don't even know a standard exists, let alone use it as a standard reference source). Other Ada 83 compilers copied this innovation from Ada/Ed. So I certainly don't oppose the general idea, and indeed the general idea is a good one, *if* the standard is written in an aggressively accessible style. For the Ada 83 standard, I think this criterion was usually met. For the Ada 95 standard, it makes better sense to decide on a case by case basis if an RM reference is helpful. That is why my suggestion is to consider individual examples where an RM reference would be helpful, rather than discussing the point as a general abstract issue. Robert Dewar Ada Core Technologies -----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own