> On Aug 17, 2020, at 8:07 AM, Remi Forax <fo...@univ-mlv.fr> wrote:
>
> static void foo() {
> sealed interface I {}
>
> record Foo implements I {}
> }
>
> but this code does not compile because Foo is a local class and a local class
> can not implement a sealed interface.
This scenario is not directly covered by the specs, because local interfaces
are a feature of the Records JEP, while 'sealed' is a feature of the Sealed
Classes JEP. (If we'd noticed the interaction, we could have specified Sealed
Classes in terms of the "Local Static Interfaces and Enum Classes" changes. But
if those changes are finalized in 16, the point will be moot.)
However, we *did* make a deliberate choice that a local *class* cannot be
'sealed' at all, and that restriction should naturally apply to local
interfaces, too:
"It is a compile-time error if a local class declaration contains any of the
access modifiers public, protected, or private (6.6), or any of the modifiers
static (8.1.1), sealed or non-sealed (8.1.1.2)."
I kind of think this is overly-restrictive, but it was a safe way to sidestep
all the questions that arise due to classes being "unavailable" from a certain
scope. I think it's worth thinking more carefully about this in the next
iteration.
