The Go FAQ has another, perhaps slightly more applicable, entry:
https://go.dev/doc/faq#t_and_equal_interface
Basically, even though *packet satisfies the Packet interface,
interface {
Get() *packet
}
Is different than
interface {
Get() Packet
}
And one isn't directly convertible into the other. In Go, interface
signatures must match _exactly_ in order to satisfy an interface.
Jason
On Monday, October 28, 2024 at 3:44:37 PM UTC-4 Marvin Renich wrote:
> * Log4bob <qdon...@gmail.com> [241028 08:47]:
> >
> >
> > Given there's a generic interface:
> > type Packet interface { Content() int } type Recycler[T any] interface {
> > Get() *T }
> >
> > and their implementation:
> > type packet struct { content int } type BaseRecycler[T any] struct { t T
> }
> >
> > its impossible to convert the implementation to the interface:
> > r := &BaseRecycler[packet]{} r1 := r.(Recycler[Packet])
> > fmt.Println(r3.Get().Content()) // compile error: Unresolved reference
> > 'Content'
> >
> > here is a live code example: https://go.dev/play/p/qbnYfyDd22A
> >
> > The error is because the Packet interface align with the *packet instead
> of
> > packet. Could anyone suggest how to handle this?
>
> If you uncomment line 39 (assignment to r3), add «_ = r3» to avoid
> "unused variable" error, and run it, you get a runtime panic. Your
> primary problem is related to this FAQ:
>
> https://go.dev/doc/faq#convert_slice_of_interface
>
> because BaseRecycler[packet] is "struct { t packet }" not "struct { t
> Packet }" so r is *struct { t packet }, which has a different, and
> differently sized, internal representation.
>
> What are you really trying to do?
>
> ...Marvin
>
>
--
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 visit
https://groups.google.com/d/msgid/golang-nuts/8f1c7a3d-d71b-4a8b-bee8-376c2ffed215n%40googlegroups.com.
