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 From: "Randy Brukardt" Newsgroups: comp.lang.ada Subject: Re: The future of Spark . Spark 2014 : a wreckage Date: Thu, 11 Jul 2013 19:07:24 -0500 Organization: Jacob Sparre Andersen Research & Innovation Message-ID: References: <7ebe0439-fa4c-4374-a6c7-365ac78e6e39@googlegroups.com> <2bvcgf0jmjcv$.79izri1n5n9r.dlg@40tude.net> NNTP-Posting-Host: static-69-95-181-76.mad.choiceone.net X-Trace: loke.gir.dk 1373587645 29533 69.95.181.76 (12 Jul 2013 00:07:25 GMT) X-Complaints-To: news@jacob-sparre.dk NNTP-Posting-Date: Fri, 12 Jul 2013 00:07:25 +0000 (UTC) X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2900.5931 X-RFC2646: Format=Flowed; Original X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.6157 Path: border1.nntp.ams3.giganews.com!border1.nntp.ams2.giganews.com!border3.nntp.ams.giganews.com!border1.nntp.ams.giganews.com!nntp.giganews.com!de-l.enfer-du-nord.net!feeder2.enfer-du-nord.net!usenet-fr.net!feed.ac-versailles.fr!news.ecp.fr!news.jacob-sparre.dk!loke.jacob-sparre.dk!pnx.dk!.POSTED!not-for-mail X-Original-Bytes: 2936 Xref: number.nntp.dca.giganews.com comp.lang.ada:182478 Date: 2013-07-11T19:07:24-05:00 List-Id: "Dmitry A. Kazakov" wrote in message news:2bvcgf0jmjcv$.79izri1n5n9r.dlg@40tude.net... > On Thu, 11 Jul 2013 03:10:51 -0700 (PDT), vincent.diemunsch@gmail.com > wrote: > >> Spark syntax needs to be different from Ada syntax because they >> manipulate >> different things : Ada manipulates types like boolean, integers. Spark >> annotations manipulates propositions based on abstraction of types (that >> I >> call categories). > > Yes this is a crucial point. These are two different languages where one > (Ada) is a subject of another (SPARK). Statements in these languages > should > be visually distinct. The problem here is that there is a strong overlap in these annotations. If you make them completely distinct, you'll have to write most of them twice (especially globals contracts, which you'll want for the optimization/code generation benefits, and preconditions and predicates, because they expose what otherwise are checks buried in subprogram bodies [where they never can be eliminated] to the compiler [which can then eliminate them from the call site - no matter whether you are using proofs or not]). These to me are a code quality issue, and items intended for the Ada compiler have to be in the Ada syntax.) And I agree that you don't want to make them completely the same either (Ada has no use for the "depends" annotation that I can see; Ada code shouldn't have items in it that are of no use to an Ada compiler). Which leaves us with a problem that isn't obvious to solve. AdaCore is trying. Anyway, I've said enough on this topic. Randy.