More support for Swift 6.

[mbrandonw]

No description provided.

[NachoSoto]

I understand this, but unfortunately this means that because Combine is stuck in the past, you can't do this anymore:

publisher.values.eraseToStream()

[stephencelis]

Does a @preconcurrency import help with that? Or worst case, a @retroactive @unchecked Sendable conformance for the publisher in question?

[NachoSoto]

Does a @preconcurrency import help with that?

Nope

a @retroactive @unchecked Sendable conformance for the publisher in question?

Yeah but that would silence all other issues related to mis-using Publishers.

[NachoSoto]

Any chance of relaxing this requirement? We'll be stuck on 1.1.0 otherwise to be able to keep supporting Combine.

[stephencelis]

@NachoSoto We recently introduced a conditional conformance to UncheckedSendable here: #44

Can you use that?

[NachoSoto]

Yes that's perfect thank you!

Ended up doing this (AnyAsyncSequence is our own type to deal with the Failure associatedtype availability):

extension Publisher where Output: Sendable {
  public func eraseToAnyAsyncSequence() -> AnyAsyncSequence<Output> {
    // Combine does not support Swift concurrency, so we rely on `ConcurrencyExtras`
    // allowing this.
    UncheckedSendable(values).eraseToAnyAsyncSequence()
  }
}