on goto
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From: Nick Keighley on 8 May 2010 12:33 On 8 May, 07:50, "io_x" <a...(a)b.c.invalid> wrote: > "Lie Ryan" <lie.1...(a)gmail.com> ha scritto nel messaggionews:4be4b38f$1(a)dnews.tpgi.com.au... > > On 05/08/10 10:39, Lie Ryan wrote: > >> I've never heard of any programming languages that doesn't support > >> recursion. > > > except for assembly, perhaps... or some very ancient or jokular languages > > with assembly is possible to write recursions functions too depends on the architecture
From: Nick Keighley on 8 May 2010 12:34 On 8 May, 11:25, "Nathan Baker" <nathancba...(a)gmail.com> wrote: > "Juha Nieminen" <nos...(a)thanks.invalid> wrote in message > news:4be50dcf$0$2544$7b1e8fa0(a)news.nbl.fi... > > In comp.lang.c++ io_x <a...(a)b.c.invalid> wrote: > >> with assembly is possible to write recursions functions too > > > That's like saying that C supports object-oriented programming. > > Of course it does! C certainly has support for data structures. > > There is absolutely no high-level language feature that can't also be > implemented in C and ASM. the Turing tar pit where everything is possible and nothing is feasible
From: Keith Thompson on 8 May 2010 12:41 Juha Nieminen <nospam(a)thanks.invalid> writes: > In comp.lang.c++ io_x <a(a)b.c.invalid> wrote: >> with assembly is possible to write recursions functions too > > That's like saying that C supports object-oriented programming. Depending on the architecure, not really. Supporting full object-orientation in C can be quite difficult. For some assembly languages (certainly for the very few I've used), recursion is just a matter of having a subroutine call itself. -- Keith Thompson (The_Other_Keith) kst-u(a)mib.org <http://www.ghoti.net/~kst> Nokia "We must do something. This is something. Therefore, we must do this." -- Antony Jay and Jonathan Lynn, "Yes Minister"
From: Nick on 8 May 2010 14:57 Keith Thompson <kst-u(a)mib.org> writes: > Juha Nieminen <nospam(a)thanks.invalid> writes: >> In comp.lang.c++ io_x <a(a)b.c.invalid> wrote: >>> with assembly is possible to write recursions functions too >> >> That's like saying that C supports object-oriented programming. > > Depending on the architecure, not really. Supporting full > object-orientation in C can be quite difficult. For some assembly > languages (certainly for the very few I've used), recursion is just > a matter of having a subroutine call itself. And, in all but the most trivial cases, using a couple of push/pop instructions to keep some state between calls. It's certainly easier to write recursive functions in assembly than in old "line number only and no local variables" BASIC. -- Online waterways route planner | http://canalplan.eu Plan trips, see photos, check facilities | http://canalplan.org.uk
From: Richard Heathfield on 8 May 2010 16:57
Juha Nieminen wrote: > In comp.lang.c++ Richard Heathfield <rjh(a)see.sig.invalid> wrote: >> Juha Nieminen wrote: >>> In comp.lang.c++ Richard Heathfield <rjh(a)see.sig.invalid> wrote: >>>> If the data are sorted, bsearch. >>>> >>>> If not, why not? >>>> >>>> In any case, your loop condition expressions do not correctly describe >>>> the conditions under which the loop will terminate. Please rewrite your >>>> example so that they do, and then by all means ask me again if you wish. >>> No offense, but it always amuses me how some C programmers try to >>> wiggle themselves out of actually giving honest answers when they are >>> presented with problematic situations related to their coding style, C, >>> or both. >> Your paragraph, above, is a classic example. > > You know, an answer of "no, you are" is rather childish. How about > presenting some actual arguments instead? Well, I thought I had done so. Sorry for the late reply, by the way - I've been kinda busy. > I gave you a piece of code and asked you to modify it to conform to > your principles. You did not do that. Who is trying to avoid answering > to a challenge here? Oh, I can modify it easily enough, and I am reasonably confident of how you'll react to the modification, but here it is anyway. I am too lazy/tired to look up your original code now, but IIRC basically you're searching through an unsorted 3D array, which I would do along these lines: /* p is a pointer to a valid "struct point" object, with x, y, and z members */ int found = 0; for(x = 0; !found && x < xlim; x++) { for(y = 0; !found && y < ylim; y++) { for(z = 0; !found && z < zlim; z++) { if(haystack[x][y][z] == needle) { found = 1; point_assign(p, x, y, z); /* that is, p.x = x; p.y = y, etc */ } } } } return found; And I know you're not going to like the extra tests any more than I like your early returns. Style issue. <snip> >>> Is it *really* that hard to simply say "yes, in this particular example >>> the 'return' is indeed the simplest way"? Does it hurt your pride or >>> something? >> What has pride got to do with it? It's common sense, that's all. The >> simplest way (and one of the fastest) to get from Tower Bridge Approach >> to St Katharine's Way is to jump off the bridge, but that doesn't >> necessarily mean it's the /best/ way. > > Then kindly show me this "best way". One man's best is another man's mediocre, and a third man's worst. <shrug> -- Richard Heathfield <http://www.cpax.org.uk> Email: -http://www. +rjh@ "Usenet is a strange place" - dmr 29 July 1999 Sig line vacant - apply within |