https://github.com/apple/swift-evolution/blob/main/proposals/0416-keypath-function-subtyping.md これって0416が必要なの？

swift-evolution/proposals/0416-keypath-function-subtyping.md at mai...

This maintains proposals for changes and user-visible enhancements to the Swift Programming Language. - apple/swift-evolution

7:50 AM

でもこれSwift6.0からって書いてあるんだよな