This is the mail archive of the guile@cygnus.com mailing list for the guile project.
Index Nav: | [Date Index] [Subject Index] [Author Index] [Thread Index] | |
---|---|---|
Message Nav: | [Date Prev] [Date Next] | [Thread Prev] [Thread Next] |
klaus@debian said: > I recently heard that scheme is turing complete, but saw no > explanation. Anyone here may explain what that means? This has nothing to do with guile, of course. ObGuile: I'm really impressed by the work going into GNOME, and especially the GIMP (although I think the gimp is SIOD based, currently). The gimp could easily become a killer free app, it's amazingly cool. And Gtk, the toolkit that they're using looks very nice. Something that can compute all functions that a universal Turing machine can. Equivalently, a language which can express a program that can compute any function that any specific Turing machine can. > What languages are not turing-complete? A language without control structures, for example. Where the only legal statements are <var> := <expr> where <expr> is some expression including, say, variables, constants and the four binary operators (+, -, *, /). A less uninteresting one would be one which included finite for loops. So you'd allow for <var> = <low> to <high> <statements which don't modify <var>> endfor That still disallows the computation of interesting functions. And partial functions, of course (where the value is undefined for some input parameters).