I didn't realize the goal was to remove the implicit conversion. Recently I made a patch to remove the subscript instead since it seemed redundant. But we could put them back, and disable the implicit conversion in Swift 4 mode. This would require an evolution proposal though. Is this still something you want to pursue or shall we just close this?

Comment by Andrew Pleshkov (JIRA)

I have a question about AnyHashable:
Found it's ok to use it as a function argument type and swift implicitly boxes any Hashable I provide there (like it does for dictionaries).
Can I be sure in such behaviour?

func foo(_ a: AnyHashable) {
    print(a)
}

foo(1) // compiles
foo("lol") // compiles

$ swift --version
Apple Swift version 3.0.2 (swiftlang-800.0.63 clang-800.0.42.1)
Target: x86_64-apple-macosx10.9

Comment by Andrew Pleshkov (JIRA)

above question is answered in SR-4273, see comments

@swift-ci create

It looks like these APIs are gone as of 66bcf5b. Should we close this bug, or is there more to do here?

Yeah, this is resolved. Will mark closed.