Error messages technically true but that does not help if several cases have the same erasure

[Maurizio Cimadamore]

On 07/07/2021 18:42, Remi Forax wrote:
> The same is true for
>    List<?> list =  null;
>    switch (list) {
>      case List l -> System.out.println("list2");
>      case List<?> l -> System.out.println("list1");
>    }
>
> which reports
> PatternMatchingWrongDominated.java:18: error: duplicate total pattern
>        case List<?> l -> System.out.println("list1");
>             ^
>
>
> I think javac should have a specific error if two cases have the same erasure.

I tend to agree, javac usually adds "detailed" messages, in parenthesis 
after the main issue. So this could be:

```
PatternMatchingWrongDominated.java:18: error: duplicate total pattern
       case List<?> l -> System.out.println("list1");
            ^
(List and List<?> have the same erasure)

```


Maurizio