Re: [RFC] Combined Comparison (Spaceship) Operator

Hey Nikita, > On 19 Jan 2015, at 14:07, Nikita Popov <nikita.ppv@gmail.com> wrote: > > I like the idea behind this (exposing internal compare_function), but I don't want to have > an extra operator for a minor use case. Please just introduce a function instead. I originally wanted a function, but an operator has some advantages. There’s no backwards-compatibility issues from function name conflicts (nor do we have to break with tradition and use a namespace despite everything else not having one). The syntax is similar to other comparisons: we don’t have lt(), gt(), lt_or_eq(), gt_or_eq(), eq() and not_eq(), we have <, >, <=, >=, == and !=. Why, then, should we have cmp() or compare()? We get to fix one of C’s mistakes here, in that C (unlike FORTRAN of all things) failed to provide a three-way comparison operation despite it being useful and often available natively. <=> has a certain brevity and is familiar to Ruby and Perl users. Plus, it looks cool and has a cool name (not really an argument, I know). Still, there is a case for a function, but I’m trying for an operator for now. I quite like how this feature makes multi-item comparisons much simpler. -- Andrea Faulds http://ajf.me/