Hi all,
In the Swift 4 Keypaths proposal [0161] there seem to be several types
that are unimplemented (or not working as I expect them to), and I'm not
sure whether these are simply unfinished in Beta 1, or just ideas that
weren't accepted.
For instance, according to the proposal AnyKeyPath is supposed to be
fully type-erased and access properties as optionals at run-time, but
using it I only get the compile-time error "Type "FooClass" has no
subscript members", even when applied to objects that still have the
original type of the KeyPath's root.
Even if I use PartialKeyPath<Root> I get the same error:
--
var tester = TestClass(name: "steve")
let tester_path = \TestClass.name
let partial_path:PartialKeyPath<TestClass> = tester_path
let name = tester[keyPath: partial_path] /// no subscript members error
here
--
Only when I either use the original path variable, or cast it to
KeyPath<TestClass, String>, am I able to access the property without an
error. I am wanting to use KeyPaths in a more generic way, so the
AnyKeyPath and PartialKeyPath would be helpful. Does anyone have insight
into the status of these KeyPath types?
regards,
-brett
_______________________________________________
swift-users mailing list
swift-users@swift.org
https://lists.swift.org/mailman/listinfo/swift-users
