If you're sure that T is an int or a string, then why not constrain it as such? https://go.dev/play/p/1kT6EacMHco
You could go further and constrain it to allow any type with ordering defined: https://go.dev/play/p/il5koj1RPkh If you want to allow any kind of comparable key in your set, one could observe that essentially you're trying to solve the same problem that the fmt package is solving when it converts maps to string. It uses the internal fmtsort <https://pkg.go.dev/internal/fmtsort> package, which, as luck would have it, has been factored out into an externally available package <https://pkg.go.dev/github.com/rogpeppe/go-internal/fmtsort>. So you could do this: https://go.dev/play/p/oKTGSm_o22a To answer the specific question you asked, there is an issue that tracks the ability to do a switch directly on a type parameter: https://github.com/golang/go/issues/45380 But you can also work around the lack of that feature by doing something like this: https://go.dev/play/p/3C2a61Ojbxs Hope this helps, rog. On Tue, 8 Nov 2022 at 08:53, 'Mark' via golang-nuts < golang-nuts@googlegroups.com> wrote: > Given a function: > > func F[T comparable](a T) { > } > > is it possible to check T's type inside F? > > My use case is that I have a function with signature G[T comparable](x > []T) and inside G I want to sort the elements in slice x where T could be > int or string. > > This arises in a tiny generic set module I've created: > https://github.com/mark-summerfield/gset > In the String() method I want to return a string with the elements sorted > (for human readability and for testing convenience); but at the moment I > can only do this by converting all elements to strings and sorting them > which isn't good for ints. > > -- > You received this message because you are subscribed to the Google Groups > "golang-nuts" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to golang-nuts+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/golang-nuts/e746f065-24fa-474a-90ec-2d8367bf3e3bn%40googlegroups.com > <https://groups.google.com/d/msgid/golang-nuts/e746f065-24fa-474a-90ec-2d8367bf3e3bn%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/CAJhgacibPQ%3DbgK74G4YSiyHdQQrNZJpahFph3Zz2%2BhDe_2j_0g%40mail.gmail.com.
