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: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: Generators/coroutines in future Ada? Date: Tue, 11 Jul 2017 22:25:18 +0200 Organization: Aioe.org NNTP Server Message-ID: References: NNTP-Posting-Host: MajGvm9MbNtGBKE7r8NgYA.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 X-Notice: Filtered by postfilter v. 0.8.2 Content-Language: en-US Xref: news.eternal-september.org comp.lang.ada:47364 Date: 2017-07-11T22:25:18+02:00 List-Id: On 2017-07-11 21:22, J-P. Rosen wrote: > Le 11/07/2017 à 20:36, Victor Porton a écrit : >> This state also includes the point of execution (like "We are in the second >> loop in its second operator.") >> >>> This can easily be achieved with a function within a package, where the >>> package serves to protect and hide the function's state. >> Ada currently has no support to save such (point of execution) states. > It has. Make your generator a task, and have an accept when the data is > ready, which can be nested as deep as you want in any construct. > > A task is a perfect abstraction for a thread of control that maintains > its own execution state! Except that no control is required. I don't understand what is wrong with: type Stateful is limited private; function Generate (X : not null access Stateful) return Things; -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de