> On Nov 1, 2017, at 9:16 AM, Ben Cohen via swift-dev <swift-dev@swift.org> > wrote: > > > >> On Oct 31, 2017, at 10:11 PM, Chris Lattner via swift-dev >> <swift-dev@swift.org> wrote: >> >> On Oct 31, 2017, at 9:07 AM, Stephen Canon via swift-dev >> <swift-dev@swift.org> wrote: >>> [Replying to the thread as a whole] >>> >>> There have been a bunch of suggestions for variants of `==` that either >>> trap on NaN or return `Bool?`. I think that these suggestions result from >>> people getting tunnel-vision on the idea of “make FloatingPoint equality >>> satisfy desired axioms of Equatable / Comparable”. This is misguided. Our >>> goal is (should be) to make a language usable by developers; satisfying >>> axioms is only useful in as much as they serve that goal. >>> >>> Trapping or returning `Bool?` does not make it easier to write correct >>> concrete code, and it does not enable writing generic algorithms that >>> operate on Comparable or Equatable. Those are the problems to be solved. >> >> +100. Swift isn’t the first language to face the problems of floating >> point, nor is it the first to try to shoehorn it into a framework like >> Equatable. > > Java and C# do not have this problem with their generic algorithms (albeit > possibly because of limitations in their languages that Swift doesn’t have). > Swift is setting itself up as a major language with confusing and > unjustifiable behavior by comparison. That some other languages are also bad > at this doesn’t seem relevant.
C++ has exactly this problem, std::sort on a std::vector<double>. I haven’t seen the world burn down in practice. -Chris _______________________________________________ swift-dev mailing list swift-dev@swift.org https://lists.swift.org/mailman/listinfo/swift-dev
