> On Jul 20, 2016, at 10:12 AM, Arnold Schwaighofer via swift-evolution > <[email protected]> wrote: > >> >> On Jul 20, 2016, at 9:54 AM, Andrew Trick <[email protected]> wrote: >> >> >>> On Jul 20, 2016, at 9:44 AM, Arnold Schwaighofer <[email protected]> >>> wrote: >>> >>> >>> The question is are they relying on the non-@objc post-condition when the >>> API returns true? If they were to implement something like array they might. >> >> The conservative thing to do is not make that promise for now and address >> need later if it’s important. Conservative makes sense to me given the >> current level of confusion. > >>>> >>>> That said, something like “isUniquelyReferencedNativeSwift” would work >>>> assuming that’s semantically correct (“native" Swfit objects do not >>>> inherit from NSObject). “isKnownUniquelyReferenced” would be fine with a >>>> warning in the doc comment that it may always return false for objc >>>> objects. >>> >>> >>> Native swift objects are the ones that use native swift reference counting >>> and don’t alias Objc class instances. That is at least how we have defined >>> it at the SIL (Builtin.NativeObject vs Builtin.UnknownObject) level: >>> >>> >>> * A ``Builtin.NativeObject`` may alias any native Swift heap object, >>> including a Swift class instance, a box allocated by ``alloc_box``, >>> or a thick function's closure context. >>> It may not alias natively Objective-C class instances. >>> >>> >>> I think at the language/stdlib level the “native” concept is implementation >>> detail that is not witnessed other than with the non-@objc requirement of >>> ManageBufferPointer and isUniquelyReferencedNonObjC, i.e at the >>> language/stdlib level we call “native” "non-@objc”. Which IMO is more >>> descriptive. >> >> I totally agree, but people can’t have it both ways. You can’t avoid a >> negative in the name and refuse to define the positive nomenclature. >> >>> I understand the desire to remove Objc’ness from API names that can be used >>> on platforms without ObjC. >> >> Me too. >> >> +1 forisKnownUniquelyReferenced, with clarifying doc comments > > > Do we continue promise that “isKnownUniquelyReferenced” returns false for > non-@objc objects in the comments?
I think the conservative answer is yes. Since there might be clients relying on the behavior. _______________________________________________ swift-evolution mailing list [email protected] https://lists.swift.org/mailman/listinfo/swift-evolution
