On Mon, May 3, 2021 at 6:44 PM Delta Echo <deltaecho...@gmail.com> wrote:
> Hi, Is there any document that explains how recursive type definitions like > > type stateFn func(*Scanner) stateFn > > are handled in Go? Not sure what "handle" means in this case. The language specs do not mention recursive types, so what follows is my opinion only. A recursive type is a type size of which cannot be computed because for that you need to know its size in the first place. So `type t struct { t }` is recursive: https://play.golang.org/p/M64qW_XnnsG But `type t struct { *t }` is not: https://play.golang.org/p/7EE2hzcRst1 because the fixed size of a pointer "breaks" the recursive chain. In this ad hoc definition `type stateFn func(*Scanner) stateFn` is not recursive and thus compiles just fine: https://play.golang.org/p/sLDd4K58FDG -- 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/CAA40n-UJ5Yj6akZbKXq4AY0n6XJE9JU1Ot_LXgLSVFxxmRPGDA%40mail.gmail.com.