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=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,cae92f92d6a1d4b1 X-Google-NewGroupId: yes X-Google-Attributes: gida07f3367d7,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII Path: g2news2.google.com!postnews.google.com!a28g2000prb.googlegroups.com!not-for-mail From: Adam Beneschan Newsgroups: comp.lang.ada Subject: Re: Ada.Execution_Time Date: Tue, 14 Dec 2010 07:51:20 -0800 (PST) Organization: http://groups.google.com Message-ID: References: <4d05e737$0$6980$9b4e6d93@newsspool4.arcor-online.net> NNTP-Posting-Host: 66.126.103.122 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable X-Trace: posting.google.com 1292341911 4321 127.0.0.1 (14 Dec 2010 15:51:51 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Tue, 14 Dec 2010 15:51:51 +0000 (UTC) Complaints-To: groups-abuse@google.com Injection-Info: a28g2000prb.googlegroups.com; posting-host=66.126.103.122; posting-account=duW0ogkAAABjRdnxgLGXDfna0Gc6XqmQ User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0; WOW64; SLCC1; .NET CLR 2.0.50727; Media Center PC 5.0; .NET CLR 3.5.21022; .NET CLR 3.5.30729; .NET CLR 3.0.30618; .NET4.0C),gzip(gfe) Xref: g2news2.google.com comp.lang.ada:16902 Date: 2010-12-14T07:51:20-08:00 List-Id: On Dec 14, 12:17=A0am, "Vinzent Hoefler" <0439279208b62c95f1880bf0f8776...@t-domaingrabbing.de> wrote: > > The logic is that you need a "null;" statement when there is nothing in= some > > list of statements. A pragma (or label) is not "nothing", so the requir= ement > > for "null;" is illogical in those cases. > > I believe, back in the old days, there was a requirement that the presenc= e or > absence of a pragma shall have no effect on the legality of the program, = wasn't > it? RM83 2.8(8): "An implementation is not allowed to define pragmas whose presence or absence influences the legality of the text outside such pragmas." But note that this applied only to *implementation-defined* pragmas; language-defined pragmas could influence legality (in particular, the INTERFACE pragma could make an illegal program, i.e. one in which a subprogram declaration didn't have a corresponding body, legal). I don't think this was intended to be a statement about the *syntax* rules, since the syntax rules are defined by the language and can't be changed by the implementation, although I suppose that this rule could have been a reflection of an unstated principle that was used when the syntax rules were designed. The current version of this rule is in 2.8(16-19) and is only Implementation Advice. -- Adam > > Well, even if it just was that it "shall have no effect on a legal progra= m", I > still wonder why it is so necessary to introduce the possibility to turn = an > illegal program (without the null statement) into a legal one merely by a= dding > some random pragma where a "sequence of statements" was expected. A pragm= a is > /not/ a statement. > > I agree with Georg here, this is an unnecessary change with no apparent u= se, > it doesn't support neither of the three pillars of the Ada language "safe= ty", > "readability", or "maintainability". > > Vinzent. > > -- > Beaten by the odds since 1974.