Using qualified enum in `old` switch

[David Alayachew]

CC'ing the Amber Dev Team.

On Mon, Jul 10, 2023 at 4:21 AM Mikhail Pyltsin <pyltsinm at gmail.com> wrote:

>   Hi!
> I am investigating a new version of jep440+441
> (
> https://cr.openjdk.org/~gbierman/jep440%2B441/jep440+441-20230612/specs/patterns-switch-record-patterns-jls.html
> )
> After `2023-06-12: Misc editorial changes.` I can't find any explicit
> mention that it is allowed to use qualified names for enums in `old` switch.
> But according to https://openjdk.org/jeps/441 it must be allowed
> ```
>
> static void goodEnumSwitch2(Coin c) {
>     switch (c) {
>         case HEADS -> {
>             System.out.println("Heads");
>         }
>         case Coin.TAILS -> {    // Unnecessary qualification but allowed
>             System.out.println("Tails");
>         }
>     }
> }
>
>
> ```
> before  `2023-06-12: Misc editorial changes.`, It was
> ```Every case constant must be either (1) the null literal, (2) a
> constant expression (15.29
> <https://docs.oracle.com/javase/specs/jls/se19/html/jls-15.html#jls-15.29>),
> or (3) the (simple or qualified) name of an enum constant (8.9.1
> <https://docs.oracle.com/javase/specs/jls/se19/html/jls-8.html#jls-8.9.1>);
> otherwise a compile-time error occurs. A single null case constant may
> also be paired with the default keyword.
> ```,  but now there is no mention of the type of enum names.
>
> Could you help me, which point allows it now?
>
> This question arose because the next code doesn't produce errors:
> ```
>     enum EN{A, B}
>
>     public void test(EN en) {
>         switch (en) {
>             case A -> System.out.println("a");
>             case EN.A -> System.out.println("a too");
>             case EN.B -> System.out.println("b");
>         }
>     }
> ```
> Is this expected?
>
>
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