229     type Output = Delta;  typedef
241     type Output = Self;  typedef
244     fn add(self, rhs: Delta) -> Self::Output {  in add()  argument
261     type Output = Self;  typedef
264     fn sub(self, rhs: Delta) -> Self::Output {  in sub()  argument
291     type Output = Self;  typedef
309     type Output = Self;  typedef
312     fn sub(self, rhs: Self) -> Self::Output {  in sub()  argument
327     type Output = Self;  typedef
330     fn mul(self, rhs: i64) -> Self::Output {  in mul()  argument
345     type Output = i64;  typedef
348     fn div(self, rhs: Self) -> Self::Output {  in div()  argument