func mockable<ReturnType >(ParameterType ..., function: String, file: StaticString , line: UInt) -> MockableSubscript .Writable<ReturnType > Creates a
MockableSubscript.Writable for a subcript.func mockable<ReturnType >(ParameterType ..., function: String, file: StaticString , line: UInt) -> MockableSubscript .Readable<ReturnType > Creates a
MockableSubscript.Readable for a subcript.