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=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,703c4f68db81387d X-Google-Thread: 109fba,703c4f68db81387d X-Google-Thread: 115aec,703c4f68db81387d X-Google-Thread: f43e6,703c4f68db81387d X-Google-Attributes: gid103376,gid109fba,gid115aec,gidf43e6,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news1.google.com!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: Peter Amey Newsgroups: comp.lang.ada,comp.lang.c++,comp.realtime,comp.software-eng Subject: Re: Teaching new tricks to an old dog (C++ -->Ada) Date: Tue, 08 Mar 2005 15:31:22 +0000 Message-ID: <395uqaF5rhu2mU1@individual.net> References: <4229bad9$0$1019$afc38c87@news.optusnet.com.au> <1110032222.447846.167060@g14g2000cwa.googlegroups.com> <871xau9nlh.fsf@insalien.org> <3SjWd.103128$Vf.3969241@news000.worldonline.dk> <87r7iu85lf.fsf@insalien.org> <1110052142.832650@athnrd02> <1110284070.410136.205090@o13g2000cwo.googlegroups.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Trace: individual.net /3IahiYwB77o3Oh64mUaggdSPMP49O4JAec8+nGWM3lkFFqpk= User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en In-Reply-To: <1110284070.410136.205090@o13g2000cwo.googlegroups.com> Xref: g2news1.google.com comp.lang.ada:8861 comp.lang.c++:44607 comp.realtime:1066 comp.software-eng:4619 Date: 2005-03-08T15:31:22+00:00 List-Id: Hans Malherbe wrote: >>support efficient, real-time safe environments > > > Can you explain the "real-time" part? > > Reading this thread, it seems to me Ada's focus is on safety rather > than efficiency. > These safety constraints also tend to limit expressiveness. Not that > safety is bad, just that it's not free. > Actually, a close reading of the thread should have made it clear that the additional safety is indeed "free". Since the majority of Ada's checks are compile time they do not impact on run-time efficiency. Where Ada's goals can only be met by run-time checks these are no more expensive than equivalent manually-inserted checks in any other language (and are often less because Ada provides the compiler with more information by which to judge when they can safely be optimised away). They can, in any case be turned off if the user requires a different performance/safety tradeoff. It should also have been clear from the thread that Ada imposes no limits on expressiveness. Can you say what led you to the opposite conclusion? Peter