Derive Macro SaturatingSub 

#[derive(SaturatingSub)]

Implements num::traits::SaturatingSub for a struct by delegating to each field.

Example

#[derive(SaturatingSub)]
struct MyStruct(usize);

adds

impl num::traits::SaturatingSub for MyStruct {
    fn saturating_sub(&self, v: &Self) -> Self {
        Self(self.0.saturating_sub(&v.0))
    }
}