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: 103376,64fe8f87aae99538 X-Google-Attributes: gid103376,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news1.google.com!postnews.google.com!59g2000hsb.googlegroups.com!not-for-mail From: Maciej Sobczak Newsgroups: comp.lang.ada Subject: Re: How to return an empty aggregate Date: Thu, 3 Apr 2008 02:09:11 -0700 (PDT) Organization: http://groups.google.com Message-ID: <945217e8-ec37-4a33-9847-28e8e7d55798@59g2000hsb.googlegroups.com> References: NNTP-Posting-Host: 128.141.45.224 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Trace: posting.google.com 1207213751 4727 127.0.0.1 (3 Apr 2008 09:09:11 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Thu, 3 Apr 2008 09:09:11 +0000 (UTC) Complaints-To: groups-abuse@google.com Injection-Info: 59g2000hsb.googlegroups.com; posting-host=128.141.45.224; posting-account=bMuEOQoAAACUUr_ghL3RBIi5neBZ5w_S User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en-US; rv:1.8.1.13) Gecko/20080311 Firefox/2.0.0.13,gzip(gfe),gzip(gfe) Xref: g2news1.google.com comp.lang.ada:20771 Date: 2008-04-03T02:09:11-07:00 List-Id: On 3 Kwi, 07:02, george.p...@gmail.com wrote: > Sorry, maybe I am missing something but what's practical sense of > having non-abstract null record implementation of interface(s)? Stateless strategy patterns? Factories? Finite state machines (no need for state within state)? Actually, most of the design patterns I can think of make sense in some stateless form, because the concrete *type* of the object is often enough to play the role of a state at some higher level. Interfaces are more about operations than about data. -- Maciej Sobczak * www.msobczak.com * www.inspirel.com