Borrowing func in noncopyable enum

Using Swift
1

Will borrowing funcs in enums be possible in the future?
See the following error where bla() cannot be called twice.

struct A: ~Copyable {
          func bla() {
                  print("A bla")
          }
  }
E>struct B: ~Copyable {
          func bla() {
                  print("B bla")
          }
  }
E>enum E: ~Copyable {
          case a(A)
          case b(B)
  
          consuming func bla() {
                  switch consume self {
                  case .a(let a):
                          a.bla()
                  case .b(let b):
                          b.bla()
                  }
          }
  }
  
  struct Laber {
          func laber() {
                  let e = E.a(A())
                  e.bla()
                  //e.bla() // bla.swift:27:21: error: 'e' consumed more than once
          }
  }
  
  let laber = Laber()
  laber.laber()

Without "consume self" the following error is generated:

bla.swift:16:24: error: noncopyable binding being pattern-matched must have the 'consume' operator applied
1 Like
2

Yeah, that is something we plan to work on soon.

3 Likes