[Pitch] Effectful Read-only Properties

[wowbagger (冀卓疌)]

@Chris_Lattner3

In motivation, I'd mention the async sequence proposal as further motivation for this. It had to turn a few get-only properties on sequence into functions because of lack of this.

I concur. I was thinking about the discussion about AsyncSequence.first() while reading this proposal.

It was also mentioned in the concurrency manifesto:

Swift currently doesn't allow property accessors to throw or be async . When this limitation is relaxed, it would be straight-forward to allow actor var s to provide the more natural API.