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,FREEMAIL_FROM autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: a07f3367d7,39579ad87542da0e X-Google-Attributes: gida07f3367d7,public,usenet X-Google-NewGroupId: yes X-Google-Language: ENGLISH,UTF8 X-Received: by 10.66.251.163 with SMTP id zl3mr7696444pac.39.1367837748667; Mon, 06 May 2013 03:55:48 -0700 (PDT) Path: ln4ni1493pbb.0!nntp.google.com!npeer03.iad.highwinds-media.com!feed-me.highwinds-media.com!cyclone03.ams2.highwinds-media.com!news.highwinds-media.com!voer-me.highwinds-media.com!newsfeed.eweka.nl!eweka.nl!feeder3.eweka.nl!de-l.enfer-du-nord.net!feeder1.enfer-du-nord.net!gegeweb.org!aioe.org!.POSTED!not-for-mail From: =?utf-8?Q?Yannick_Duch=C3=AAne_=28Hibou57?= =?utf-8?Q?=29?= Newsgroups: comp.lang.ada Subject: Re: Seeking for papers about tagged types vs access to subprograms Date: Mon, 06 May 2013 12:55:31 +0200 Organization: Ada @ Home Message-ID: References: NNTP-Posting-Host: 01/BPNoqk8s7XmPzrYdoUA.user.speranza.aioe.org Mime-Version: 1.0 X-Complaints-To: abuse@aioe.org User-Agent: Opera Mail/12.15 (Linux) X-Notice: Filtered by postfilter v. 0.8.2 X-Received-Bytes: 3272 Content-Type: text/plain; charset=utf-8; format=flowed; delsp=yes Content-Transfer-Encoding: Quoted-Printable Date: 2013-05-06T12:55:31+02:00 List-Id: Le Mon, 06 May 2013 12:18:40 +0200, Dmitry A. Kazakov = a =C3=A9crit: > On Mon, 06 May 2013 12:00:25 +0200, Yannick Duch=C3=AAne (Hibou57) wro= te: > >> Or else, may be it suggest types should rather be tagged by default > > No. All untagged types should have untagged classes. If I understand you correctly, that was something very close I was = thinking about when reading the RM page about user=E2=80=91defined index= ing (and = other tagged=E2=80=91types only allowed features), I just though =E2=80=9C= so, why not = considerer untagged types has a fixed static class (*) and on that basis= , = naturally allow the same definitions to be applied to untagged types=E2=80= =9D. = While some features are defined for tagged types only, no requirement is= = never made any where for these same tagged types to be derived, so it = could be defined for untagged types as well (or else I am missing = something). (*) class with no dispatching or deterministic dispatching, so would be = = untagged, indeed, if I understand you correctly. I feel the status distinction between tagged and untagged types as an = issue in some ways, this breaks something in the big picture, and break = = Ada, the language, in two too much distinct and foreign parts. That's no= t = that I'm against tagged types, just that I would prefer to not force the= = use of tagged types (hence the =E2=80=9Clack of orthogonality=E2=80=9D);= tagged are = sometime nice, sometime not nice, that depends on the area, on the = requirements, =E2=80=A6, both should be treated equally with regards to = primitives = and constructs, except for any primitives and construct which would = *requires* there are indeed tagged (non=E2=80=91deterministic members an= d = sub=E2=80=91programs) classes (like any operations which involves classe= s, as an = immediate example). -- = =E2=80=9CSyntactic sugar causes cancer of the semi-colons.=E2=80=9D [1] =E2=80=9CStructured Programming supports the law of the excluded muddle.= =E2=80=9D [1] [1]: Epigrams on Programming =E2=80=94 Alan J. =E2=80=94 P. Yale Univers= ity