Allow Infix on enum

[bishabosha]

Minimized code

example 1:

infix enum mul[T <: Int, U <: Int] {                                                                                                                       
  case Refl(r: compiletime.ops.int.*[T,U])
}

example 2:

enum Expr {
  infix case Add(l: Expr, r: Expr)
  case Lit(i: Int)
}

Output

example 1:

1 |infix enum mul[T <: Int, U <: Int] { 
  |           ^^^
  |           Only access modifiers are allowed on enum definitions

example 2:

2 |    infix case Add(l: Expr, r: Expr)
  |          ^^^^
  |          end of statement expected but 'case' found
2 |    infix case Add(l: Expr, r: Expr)
  |               ^^^
  |               ';' expected, but identifier found

Expectation

infix is allowed for a class definition:

example 1:

infix sealed trait mul[T <: Int, U <: Int]
object mul {
  final case class Refl[T <: Int, U <: Int](r: compiletime.ops.int.*[T,U]) extends (T mul U)
}

[odersky]

That's an enhancement request, not a bug. infix behaves as is documented.

[odersky]

I think it should be a feature request. Let's try to keep the issues here focussed on actionably items.