On Thu, Dec 22, 2022 at 2:23 PM Pierre Durand <pierredur...@gmail.com> wrote:
> Is there a way to declare a "nillable" constraint that matches all types > that can be nil (pointer, slice, map, etc.) ? There is currently no way to do that. In particular, any interface type can be `nil`, therefore any such constraint would have to be satisfied by all interface types. > I would like to write a function, that receives a parameter (with a > generic type), and check if this parameter is nil. > I don't understand the point, to be honest. It seems to me `== nil` is a better way to spell that, than a function call. And a generic function can always do `v == *new(T)` to check if a value is the zero value. > I found a very ugly way to write it: https://go.dev/play/p/0g0SoTlBEgs > The problem: the map type needs more than 1 type, so I need to provide the > 3 types when I call the `IsNil()` function/ > Is there a better way ? > > Yes I know I could use `any`, and check with reflect if the value inside > the interface is nil. > But I want to know if it's possible to do it with generics. > > Thank you. > > -- > 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/2043afe5-3d18-445a-90a9-75b48d3ec078n%40googlegroups.com > <https://groups.google.com/d/msgid/golang-nuts/2043afe5-3d18-445a-90a9-75b48d3ec078n%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/CAEkBMfH-4aRxrGY2VrfWs52PecpjWR-s0yGOO7m-3%3Dpg37H9BQ%40mail.gmail.com.
