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=unavailable autolearn_force=no version=3.4.4 X-Received: by 10.129.178.65 with SMTP id q62mr2128783ywh.122.1485508843401; Fri, 27 Jan 2017 01:20:43 -0800 (PST) X-Received: by 10.157.35.89 with SMTP id k25mr501020otd.11.1485508843324; Fri, 27 Jan 2017 01:20:43 -0800 (PST) Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!2.eu.feeder.erje.net!feeder.erje.net!2.us.feeder.erje.net!feeder.usenetexpress.com!feeder1.iad1.usenetexpress.com!216.166.98.84.MISMATCH!border1.nntp.dca1.giganews.com!nntp.giganews.com!q58no402623qte.0!news-out.google.com!78ni12919itm.0!nntp.google.com!r185no584411ita.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Fri, 27 Jan 2017 01:20:42 -0800 (PST) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=85.167.236.133; posting-account=bPTmZAoAAAC_6HP9XLKB9aAAxBa6BuOR NNTP-Posting-Host: 85.167.236.133 References: <65f79e53-a468-4b77-8ee1-440c26a09371@googlegroups.com> User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: <717db8c1-f6ae-4b6f-adff-d8e5c8fbfcaa@googlegroups.com> Subject: Re: Question on type invariants From: reinkor Injection-Date: Fri, 27 Jan 2017 09:20:43 +0000 Content-Type: text/plain; charset=UTF-8 Xref: news.eternal-september.org comp.lang.ada:33188 Date: 2017-01-27T01:20:42-08:00 List-Id: On Thursday, January 26, 2017 at 9:38:21 AM UTC+1, Dmitry A. Kazakov wrote: > What you have described looks like a lazy evaluation scheme. Exactly. But no way to express this intention in a somehow explicite way in Ada? The point is to produce updates only when you need it (i.e. when you read from (use) S and A has changed since last update (of S).