Sendable enums with @Sendable case constructors

I couldn't find any information on this in the structured concurrency proposal, but has there been any discussion of making the cases of a Sendable enum act as a @Sendable function? Currently the following produces a warning:

enum Foo: Sendable {
  case bar(Int)

let f: @Sendable (Int) -> Foo =

…saying that is not @Sendable. As far as I can tell it seems @Sendable to me.

Is this theoretically possible at some point, or was it specifically disallowed for a particular reason?


I've run into something similar to this before, but in that situation it was a func rather than an enum case. This solution worked for me then; does it work here, too?

let f: @Sendable (Int) -> Foo = { .bar($0) }

Regardless, I think it is odd that this doesn't work.

Yeah that's right and I should have mentioned. Using {$0) } does get around the problem. However, it can make call sites of APIs look really bad, so I was hoping would work.

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