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=-0.9 required=5.0 tests=BAYES_00,FORGED_GMAIL_RCVD, FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,b88383a5d9c51aa0 X-Google-Attributes: gid103376,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!postnews.google.com!g19g2000yql.googlegroups.com!not-for-mail From: Maciej Sobczak Newsgroups: comp.lang.ada Subject: Re: Ada-Singleton-Why does it work like this? Date: Thu, 26 Mar 2009 06:39:26 -0700 (PDT) Organization: http://groups.google.com Message-ID: References: <5a7a870c-40e2-4803-8753-0f9cfd2b800f@k2g2000yql.googlegroups.com> <6d2b2c67-22fb-4283-87ab-58357e47d5ca@v39g2000yqm.googlegroups.com> NNTP-Posting-Host: 137.138.182.236 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Trace: posting.google.com 1238074766 13737 127.0.0.1 (26 Mar 2009 13:39:26 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Thu, 26 Mar 2009 13:39:26 +0000 (UTC) Complaints-To: groups-abuse@google.com Injection-Info: g19g2000yql.googlegroups.com; posting-host=137.138.182.236; posting-account=bMuEOQoAAACUUr_ghL3RBIi5neBZ5w_S User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.0.7) Gecko/2009021906 Firefox/3.0.7,gzip(gfe),gzip(gfe) Xref: g2news1.google.com comp.lang.ada:4331 Date: 2009-03-26T06:39:26-07:00 List-Id: On 26 Mar, 10:28, "Dmitry A. Kazakov" wrote: > This highlights the point. "Singletonness" is not a property of the type > used to implement it. Depends. The type involves not only the set of possible states, but also the set of possible operations. Is the creation as an operation part of this set? If creation belongs to the set of operations of some type, then "singletonness" is obviously a property of the type. If, on the other hand, creation does not belong to this set, then indeed these concepts are orthogonal. Can you defend the idea that creation does not belong to the type? > So the pattern is all wrong. Or not - maybe it is a way to express some property of the *type* that cannot be expressed due to the limitations in the language? -- Maciej Sobczak * www.msobczak.com * www.inspirel.com Database Access Library for Ada: www.inspirel.com/soci-ada