method WriteTo(w: Writer): tuple of (n: int64, err: error)

(int64 n, error err) WriteTo(Writer w)

func WriteTo(_ w: Writer) -> tuple of (int64, error)

func WriteTo(w Writer) tuple of (|name=n| int64, |name=err| error)

Function WriteTo(w As Writer) As Tuple (Of int64, error)