#14

Re-stated Protocol Requirement

★★★

protocols
dispatch

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protocol P {
    func f()
}

extension P {
    func f() {
        print("ext-P")
    }
}

protocol Q: P {
    func f()
}

extension Q {
    func f() {
        print("ext-Q")
    }
}

struct S: Q {}

S().f()
(S() as P).f()
(S() as Q).f()

Hint

P requires f. Q: P also requires f. S: Q doesn't implement either. With two defaults in scope (one on P, one on Q), which one becomes the witness for S's conformance to P?

Your answer