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```
```use core::ops::{Add, Sub, Mul};
use core::num::Wrapping;

macro_rules! wrapping_impl {
(\$trait_name:ident, \$method:ident, \$t:ty) => {
impl \$trait_name for \$t {
#[inline]
fn \$method(&self, v: &Self) -> Self {
<\$t>::\$method(*self, *v)
}
}
};
(\$trait_name:ident, \$method:ident, \$t:ty, \$rhs:ty) => {
impl \$trait_name<\$rhs> for \$t {
#[inline]
fn \$method(&self, v: &\$rhs) -> Self {
<\$t>::\$method(*self, *v)
}
}
}
}

/// Performs addition that wraps around on overflow.
/// Wrapping (modular) addition. Computes `self + other`, wrapping around at the boundary of
/// the type.
fn wrapping_add(&self, v: &Self) -> Self;
}

/// Performs subtraction that wraps around on overflow.
pub trait WrappingSub: Sized + Sub<Self, Output=Self> {
/// Wrapping (modular) subtraction. Computes `self - other`, wrapping around at the boundary
/// of the type.
fn wrapping_sub(&self, v: &Self) -> Self;
}

wrapping_impl!(WrappingSub, wrapping_sub, u8);
wrapping_impl!(WrappingSub, wrapping_sub, u16);
wrapping_impl!(WrappingSub, wrapping_sub, u32);
wrapping_impl!(WrappingSub, wrapping_sub, u64);
wrapping_impl!(WrappingSub, wrapping_sub, usize);

wrapping_impl!(WrappingSub, wrapping_sub, i8);
wrapping_impl!(WrappingSub, wrapping_sub, i16);
wrapping_impl!(WrappingSub, wrapping_sub, i32);
wrapping_impl!(WrappingSub, wrapping_sub, i64);
wrapping_impl!(WrappingSub, wrapping_sub, isize);

/// Performs multiplication that wraps around on overflow.
pub trait WrappingMul: Sized + Mul<Self, Output=Self> {
/// Wrapping (modular) multiplication. Computes `self * other`, wrapping around at the boundary
/// of the type.
fn wrapping_mul(&self, v: &Self) -> Self;
}

wrapping_impl!(WrappingMul, wrapping_mul, u8);
wrapping_impl!(WrappingMul, wrapping_mul, u16);
wrapping_impl!(WrappingMul, wrapping_mul, u32);
wrapping_impl!(WrappingMul, wrapping_mul, u64);
wrapping_impl!(WrappingMul, wrapping_mul, usize);

wrapping_impl!(WrappingMul, wrapping_mul, i8);
wrapping_impl!(WrappingMul, wrapping_mul, i16);
wrapping_impl!(WrappingMul, wrapping_mul, i32);
wrapping_impl!(WrappingMul, wrapping_mul, i64);
wrapping_impl!(WrappingMul, wrapping_mul, isize);

// Well this is a bit funny, but all the more appropriate.
fn wrapping_add(&self, v: &Self) -> Self {
}
}
impl<T: WrappingSub> WrappingSub for Wrapping<T> where Wrapping<T>: Sub<Output = Wrapping<T>> {
fn wrapping_sub(&self, v: &Self) -> Self {
Wrapping(self.0.wrapping_sub(&v.0))
}
}
impl<T: WrappingMul> WrappingMul for Wrapping<T> where Wrapping<T>: Mul<Output = Wrapping<T>> {
fn wrapping_mul(&self, v: &Self) -> Self {
Wrapping(self.0.wrapping_mul(&v.0))
}
}

#[test]
fn test_wrapping_traits() {
fn wrapping_sub<T: WrappingSub>(a: T, b: T) -> T { a.wrapping_sub(&b) }
fn wrapping_mul<T: WrappingMul>(a: T, b: T) -> T { a.wrapping_mul(&b) }
assert_eq!(wrapping_sub(0, 1), 255u8);
assert_eq!(wrapping_mul(255, 2), 254u8);
assert_eq!(wrapping_sub(0, 1), (Wrapping(0u8) - Wrapping(1u8)).0);
assert_eq!(wrapping_mul(255, 2), (Wrapping(255u8) * Wrapping(2u8)).0);
}

#[test]
}

#[test]
fn wrapping_is_wrappingsub() {
fn require_wrappingsub<T: WrappingSub>(_: &T) {}
require_wrappingsub(&Wrapping(42));
}

#[test]
fn wrapping_is_wrappingmul() {
fn require_wrappingmul<T: WrappingMul>(_: &T) {}
require_wrappingmul(&Wrapping(42));
}
```