From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.5-pre1 (2020-06-20) on ip-172-31-74-118.ec2.internal X-Spam-Level: X-Spam-Status: No, score=-1.9 required=3.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.5-pre1 Path: eternal-september.org!reader02.eternal-september.org!aioe.org!5WHqCw2XxjHb2npjM9GYbw.user.gioia.aioe.org.POSTED!not-for-mail From: "Dmitry A. Kazakov" Newsgroups: comp.lang.ada Subject: Re: ? How get/use a 'type' from a Ada shared library loaded at run time (plugin) ? Date: Thu, 15 Apr 2021 11:28:24 +0200 Organization: Aioe.org NNTP Server Message-ID: References: <865ff80f-0954-472b-b460-75bd63dfbecbn@googlegroups.com> NNTP-Posting-Host: 5WHqCw2XxjHb2npjM9GYbw.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.9.1 Content-Language: en-US X-Notice: Filtered by postfilter v. 0.9.2 Xref: reader02.eternal-september.org comp.lang.ada:61791 List-Id: On 2021-04-15 10:48, Daniel Norte Moraes wrote: > How use Ada 'type(s)' from an library loaded at run time (dlopen &Cia)? are they possible? Like any other type. You should not forget to initialize the library though. The library project should normally have for Library_Auto_Init use "false"; because otherwise it would likely deadlock under Windows [if you wish to make your project portable]. Under Linux I am not sure if it deadlocks, never tested for that. > My main need is to declare variables from these types or and make > dispatching calls based in these types. You cannot declare variables of types declared in a dynamically loaded library for the obvious reason that you cannot dynamically refer to a package from the library. But you can dispatch on a class-wide object which specific type is declared in a dynamically loaded library. For example you can call a dynamically loaded constructing function that returns T'Class where T is declared outside the library and then dispatch to an overridden primitive operation of S derived from T inside the library. To my understanding library initialization expands dispatching tables with all tagged types declared in the library. P.S. What happens on finalization is an intriguing question. I would rather never attempt to unload an Ada library... -- Regards, Dmitry A. Kazakov http://www.dmitry-kazakov.de