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-Language: ENGLISH,ASCII-7-bit X-Google-Thread: fac41,b2bad1e85ca20475 X-Google-Attributes: gidfac41,public X-Google-Thread: 103376,5b3c19b1631bb558 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2000-10-31 18:00:19 PST From: "Tom Hargraves" Newsgroups: comp.lang.eiffel,comp.lang.ada References: <39DCB9E3.EAE8F426@ftw.rsc.raytheon.com> <39F9FCCE.D6719C6F@ftw.rsc.raytheon.com> <1c9kvs4uvj4ofd46f7a8vq0pju596iu2gr@4ax.com> <39fed7b6@rsl2.rslnet.net> <39FF1DBD.74184FDC@worldnet.att.net> Subject: Re: The best thing/greatest feature summary Date: Tue, 31 Oct 2000 18:13:15 -0800 X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 NNTP-Posting-Host: van-port156.imag.net X-Original-NNTP-Posting-Host: van-port156.imag.net Message-ID: <39ff792d@rsl2.rslnet.net> X-Trace: 31 Oct 2000 18:00:13 -0800, van-port156.imag.net Path: supernews.google.com!sn-xit-02!sn-xit-03!supernews.com!cyclone-sjo1.usenetserver.com!news-out.usenetserver.com!cyclone.bc.net!rsl2.rslnet.net!van-port156.imag.net Xref: supernews.google.com comp.lang.eiffel:945 comp.lang.ada:1676 Date: 2000-10-31T18:13:15-08:00 List-Id: Good point James. All these ease-of-programming features come at a cost. But what is the cost here? A few strings can hardly be much of a cost nowadays. I'm not asking for a 1Mbyte dynamic .GIF icon to popup, just a routine name... These 256 byte strings could live quite happily in the corner of the xMbyte proms and nobody would even know they where there ;-) (OK, so I'm setting myself up here. There's bound to be a space shuttle designer out there who knows the weight of a byte of memory and how much it costs to put it in orbit...) Regards, Tom H. "James Rogers" wrote in message news:39FF1DBD.74184FDC@worldnet.att.net... > > > Tom Hargraves wrote: > > > > Let > > X := Ada > > Y := Java > > > > then the wish is > > > > to add java.lang.reflect 'style' routines to the ada language > > > > Here's a simple example where I'd find it useful: > > > > Quite often in user written Ada error handling packages, it is nice to be > > able to increase the detail in the error message, and be able to print or > > log the name of the routine or class in which it occured. A 'debug' mode so > > to speak. > > > > In ada I've seen this done by declaring constant strings which match (at the > > time of writing) the text to be displayed or logged. However there is > > nothing to link the content of these strings to the items they refer, so > > during the life of an application mismatches can occur. > > > > java.lang.reflect has getName, getDeclaringClass, to name but two. > > > > The java.lang.reflect 'style' of routines rely on the fact that Java > creates > a "Class" object for each class defined in a program. This "Class" > object > contains the name of the class, the name of the Super for the class, and > several other pieces of information. I, for one, do not want this extra > overhead > in realtime programs. Realtime systems are frequently constrained by > memory as well as by timing. The extra overhead of such shadow data > structures > is easily overlooked by developers. In realtime systems the consequences > of > such errors can be disasterous. > > If an Ada developer wants such a capability, then all you need is a > simple > generic package with parameters for all the items you want to identify. > > Each package can instantiate the generic with appropriate parameter > values. > The generic package would declare the "getName", "getDeclaringClass", > and > other java-like subprograms as needed. > > Jim Rogers > Colorado Springs, Colorado