extension Set where Element == Int \{

    func foo() \{

        let arr: [String] = ["hello", "world"]

        let stringSet = Set(arr) // Error: Type of expression is ambiguous without more context

    }

 

    func bar() \{

        let arr: [String] = ["hello", "world"]

        let stringSet: Set<String> = Set.init(arr) // Error: No Set<Int>.Type.init canidates produce the expected contextual result type Set<String>

    }

 

    func baz() \{

        let arr: [String] = ["hello", "world"]

        let stringSet = Set<String>(arr) // No error

    }

}