On Sun, 19 Oct 2008, Andre van Tonder wrote: > On Sun, 19 Oct 2008, John Cowan wrote: > >> The fact there's no dispute about the meaning of more than one argument, >> whereas the interpretations of zero and one arguments are all over the >> lot, suggests that the restriction is anything but arbitrary. > > They may be all over the lot, but I do not believe they are equally natural. > There seems to be only one natural interpretation. > >> The true >> underlying domain, I think, is not numbers but ordering itself (there >> is no reason why these functions could not be polymorphic, as they are in >> many other languages), and in a domain where there exist (timelessly) >> only one item, or zero items, ordering simply doesn't apply. > > Are you saying you cannot sort an empty or one-item sequence? I have > directories with zero or one entry on my computer, and I can order them fine > using various criteria without my OS complaining, and that's Windows! ;-) >
yes, but in this case, on any criterion, sorting increasing and sorting decreasing would give the same result, meaning < and > have the same result. this is, of course, impossible. the definition of monotonic increase and decrease relies on pairwise comparison; a sequence with one element is neither increasing nor decreasing. -elf _______________________________________________ r6rs-discuss mailing list [email protected] http://lists.r6rs.org/cgi-bin/mailman/listinfo/r6rs-discuss
