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!weretis.net!feeder8.news.weretis.net!news.szaf.org!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: Niklas Holsti Newsgroups: comp.lang.ada Subject: Re: array from static predicate on enumerated type Date: Thu, 18 Mar 2021 12:15:30 +0200 Organization: Tidorum Ltd Message-ID: References: <89128f73-fcc5-4e57-8067-d09877ba0211n@googlegroups.com> <6ca041f3-2669-4497-9548-2f17666702a6n@googlegroups.com> <26c44e00-a899-455a-a929-1e23c7935fe3n@googlegroups.com> <9abb081d-a323-466d-9ae8-a2fc8fa24725n@googlegroups.com> <9933c99a-46b1-4541-aa15-f5c23e92b037n@googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: individual.net yMCv+mDh3II+k6CIK8KjTw/M9/Y+AuFAqWgQ4TyTyqMYFHCeu1 Cancel-Lock: sha1:na6ozFjBi/6RG0Dk0hV7D0tNAzo= User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:78.0) Gecko/20100101 Thunderbird/78.7.0 In-Reply-To: <9933c99a-46b1-4541-aa15-f5c23e92b037n@googlegroups.com> Content-Language: en-US Xref: reader02.eternal-september.org comp.lang.ada:61610 List-Id: On 2021-03-18 3:30, Matt Borchers wrote: > On Wednesday, March 17, 2021 at 3:41:16 PM UTC-4, Dmitry A. Kazakov wrote: >> On 2021-03-17 19:44, Matt Borchers wrote: [about "sparse" enumeration subtypes defined by static predicates, and arrays indexed by such subtypes] >>> Nevertheless, it still feels like an unfinished feature as it is now. >> It is not unfinished. It is irreparably broken. > > And this does not make for good advertising for Ada. Matt, you should be aware that Dmitry has strong opinions about language and program design that are not shared by all Ada users and Ada proponents. To be sure, Ada is showing some of its age. Updates of the Ada standards have made extensive additions to the language, while taking great pains to remain mostly upwards compatible, not only in syntax and semantics but also in wider usability goals such as remaining competitive for hard-real-time embedded systems and safety-critical systems where implementation overheads and implementation complexity must be held down. This inevitably means that new high-level features such as static predicates cannot always be fully orthogonal to other features of the language. There have been suggestions and discussion here of an "Ada successor" language, and Dmitry in particular thinks that the type system should be completely overhauled for such a new language. Unfortunately there seems to be no demand from any large potential user group for such a language, or if there is demand, it is being satisfied mostly by new "grass-roots" languages such as Rust. I have some hope that the swiftly growing scope and impact of malware and SW security breaches will prompt a major effort to develop computer systems, including programming languages, which are provably secure and incorruptible, and perhaps that will be an opportunity for an Ada successor language.