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=unavailable autolearn_force=no version=3.4.4 Path: border1.nntp.dca3.giganews.com!border3.nntp.dca.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!news.snarked.org!feeder.erje.net!us.feeder.erje.net!newsfeed.fsmpi.rwth-aachen.de!news-1.dfn.de!news.dfn.de!news.uni-weimar.de!medsec1.medien.uni-weimar.de!lucks From: Stefan.Lucks@uni-weimar.de Newsgroups: comp.lang.ada Subject: Re: Is this expected behavior or not Date: Fri, 5 Apr 2013 22:38:07 +0200 Organization: Bauhaus-Universitaet Weimar Message-ID: References: <1gnmajx2fdjju.1bo28xwmzt1nr.dlg@40tude.net> <3gv2jwc95otm.pl2aahsh9ox8.dlg@40tude.net> <1gkxiwepaxvtt$.u3ly33rbwthf.dlg@40tude.net> <1fmcdkj58brky.bjedt0pr39cd$.dlg@40tude.net> <1bj564vat3q1j$.1s4d00rlzx4ux$.dlg@40tude.net> <1cfhriq4xpg9s$.3yl33z705wpn$.dlg@40tude.net> <16wai67izvmu5.13yz864sx1cqd$.dlg@40tude.net> <1xbow8ojtmac9.1sfor8ytiplgx.dlg@40tude.net> NNTP-Posting-Host: medsec1.medien.uni-weimar.de Mime-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="8323329-453900254-1365194288=:31746" X-Trace: tigger.scc.uni-weimar.de 1365194359 8865 141.54.178.228 (5 Apr 2013 20:39:19 GMT) X-Complaints-To: news@tigger.scc.uni-weimar.de NNTP-Posting-Date: Fri, 5 Apr 2013 20:39:19 +0000 (UTC) X-X-Sender: lucks@debian In-Reply-To: <1xbow8ojtmac9.1sfor8ytiplgx.dlg@40tude.net> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) X-Original-Bytes: 3842 Xref: number.nntp.dca.giganews.com comp.lang.ada:180943 Date: 2013-04-05T22:38:07+02:00 List-Id: This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-453900254-1365194288=:31746 Content-Type: TEXT/PLAIN; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE On Fri, 5 Apr 2013, Dmitry A. Kazakov wrote: > We are discussing deficiencies of Ada type system, unable to capture > relations between domain specific entities modeled as objects and types. Well, that is a broader discussion than the part I was in, that was about= =20 the need for some Universal_String type, but OK. > E.g. few built-in numeric types, which are supposed to fit everything and > expectedly fail, because predefined numbers have properties you might not > need and miss ones you do need. The Op's subtype Prim was a perfect examp= le > of such a failure. Prime numbers are neither additive nor multiplicative. > It is not a group. Yet Prime inherited the interface of a group from base > type (Positive) and there is no way to prohibit this. It also inherited t= he > order of Positives ('Succ), which is not one of Prime, and, again, there = is > no language means for fix that. Here, I have agree with you. I understand that for historical reasons Prime'Succ is actually=20 Prime'Base'Succ, and the designers of Ada 2012 have unable to get rid of=20 that without introducing too many incompatibilities. But Prime'Succ(5)=3D4 is a big OUCH! I hope that Ada 2020 (or whatever) will prohibit the attibutes Succ and=20 Pred for all subtypes with dynamic predicates! (I think, First and Last=20 are prohibited anyway.) ------ I love the taste of Cryptanalysis in the morning! ------ --Stefan.Lucks (at) uni-weimar.de, Bauhaus-Universit=E4t Weimar, Germany-- --8323329-453900254-1365194288=:31746--