On Thu, Mar 17, 2022 at 12:18 AM Alex Besogonov <alex.besogo...@gmail.com> wrote:
> No. It should be a POINTER to a struct, which would have been fine. > Instead Go's reflection incorrectly latches on the type of the embedding > structure. > Your code says: var n3 Node LockObjects(n2, n3, n1) You are thus storing a `Node`, which is a struct value, in a `Lockable`. It's not a pointer. And the `reflect` package behaves correctly. > The code is NOT using anything incorrect. > We apparently have to agree to disagree. To me, passing around an interface value where every method call panics is a clear example of incorrect code. It is like writing a Boom io.Reader and claiming that the code is correct and the language is wrong for panicing when using it. The interface is obtained through a pointer to a struct, which is > completely valid. The only problem is that this pointer is embedded inside > a struct. > > If you rewrite the code to use a named field, it would work. This means > that the language behaves differently depending on a field having a name. > Well, yes. That's the point of embedding, after all. That is working as intended. The real example would look like this: https://go.dev/play/p/mwUfh4_RBUU - > you do see why it's a tad problematic? > Not really, no. It doesn't seem to change the basic properties of the code. I don't know what the return type of `store.GetNode` is: - If it is `Lockable`, it clearly should not return a `Node` with a nil `*BasicNode` field, as that is an invalid implementation of `Lockable`. - If it is `Node`, then you clearly shouldn't check `n1 == nil`, but perhaps `n1 == nil || n1.BasicNode == nil`, before assigning it to `Lockable` (in the call to `LockObjects`). Either way, some piece of code is assigning an invalid `Node` value to a `Lockable`. That code must be fixed, to no longer do that. Neither of these pieces of code seems particularly hard to fix. > -- > 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/58d5770b-4888-4980-8f9e-c96310d57490n%40googlegroups.com > <https://groups.google.com/d/msgid/golang-nuts/58d5770b-4888-4980-8f9e-c96310d57490n%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/CAEkBMfFHQ7ugJbi%2B0G1_OF9nNX4gLBSyJ2ndmU08YnjsrUf0NA%40mail.gmail.com.
