/rust/registry/src/index.crates.io-1949cf8c6b5b557f/num-traits-0.2.19/src/ops/wrapping.rs

Source
use core::num::Wrapping;
use core::ops::{Add, Mul, Neg, Shl, Shr, Sub};

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.
pub trait WrappingAdd: Sized + Add<Self, Output = Self> {
    /// Wrapping (modular) addition. Computes `self + other`, wrapping around at the boundary of
    /// the type.
    fn wrapping_add(&self, v: &Self) -> Self;
}

wrapping_impl!(WrappingAdd, wrapping_add, u8);
wrapping_impl!(WrappingAdd, wrapping_add, u16);
wrapping_impl!(WrappingAdd, wrapping_add, u32);
wrapping_impl!(WrappingAdd, wrapping_add, u64);
wrapping_impl!(WrappingAdd, wrapping_add, usize);
wrapping_impl!(WrappingAdd, wrapping_add, u128);

wrapping_impl!(WrappingAdd, wrapping_add, i8);
wrapping_impl!(WrappingAdd, wrapping_add, i16);
wrapping_impl!(WrappingAdd, wrapping_add, i32);
wrapping_impl!(WrappingAdd, wrapping_add, i64);
wrapping_impl!(WrappingAdd, wrapping_add, isize);
wrapping_impl!(WrappingAdd, wrapping_add, i128);

/// 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, u128);

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);
wrapping_impl!(WrappingSub, wrapping_sub, i128);

/// 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, u128);

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);
wrapping_impl!(WrappingMul, wrapping_mul, i128);

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

/// Performs a negation that does not panic.
pub trait WrappingNeg: Sized {
    /// Wrapping (modular) negation. Computes `-self`,
    /// wrapping around at the boundary of the type.
    ///
    /// Since unsigned types do not have negative equivalents
    /// all applications of this function will wrap (except for `-0`).
    /// For values smaller than the corresponding signed type's maximum
    /// the result is the same as casting the corresponding signed value.
    /// Any larger values are equivalent to `MAX + 1 - (val - MAX - 1)` where
    /// `MAX` is the corresponding signed type's maximum.
    ///
    /// ```
    /// use num_traits::WrappingNeg;
    ///
    /// assert_eq!(100i8.wrapping_neg(), -100);
    /// assert_eq!((-100i8).wrapping_neg(), 100);
    /// assert_eq!((-128i8).wrapping_neg(), -128); // wrapped!
    /// ```
    fn wrapping_neg(&self) -> Self;
}

wrapping_unary_impl!(WrappingNeg, wrapping_neg, u8);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, u16);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, u32);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, u64);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, usize);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, u128);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, i8);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, i16);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, i32);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, i64);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, isize);
wrapping_unary_impl!(WrappingNeg, wrapping_neg, i128);

macro_rules! wrapping_shift_impl {
    ($trait_name:ident, $method:ident, $t:ty) => {
        impl $trait_name for $t {
            #[inline]
            fn $method(&self, rhs: u32) -> $t {
                <$t>::$method(*self, rhs)
            }
        }
    };
}

/// Performs a left shift that does not panic.
pub trait WrappingShl: Sized + Shl<usize, Output = Self> {
    /// Panic-free bitwise shift-left; yields `self << mask(rhs)`,
    /// where `mask` removes any high order bits of `rhs` that would
    /// cause the shift to exceed the bitwidth of the type.
    ///
    /// ```
    /// use num_traits::WrappingShl;
    ///
    /// let x: u16 = 0x0001;
    ///
    /// assert_eq!(WrappingShl::wrapping_shl(&x, 0),  0x0001);
    /// assert_eq!(WrappingShl::wrapping_shl(&x, 1),  0x0002);
    /// assert_eq!(WrappingShl::wrapping_shl(&x, 15), 0x8000);
    /// assert_eq!(WrappingShl::wrapping_shl(&x, 16), 0x0001);
    /// ```
    fn wrapping_shl(&self, rhs: u32) -> Self;
}

wrapping_shift_impl!(WrappingShl, wrapping_shl, u8);
wrapping_shift_impl!(WrappingShl, wrapping_shl, u16);
wrapping_shift_impl!(WrappingShl, wrapping_shl, u32);
wrapping_shift_impl!(WrappingShl, wrapping_shl, u64);
wrapping_shift_impl!(WrappingShl, wrapping_shl, usize);
wrapping_shift_impl!(WrappingShl, wrapping_shl, u128);

wrapping_shift_impl!(WrappingShl, wrapping_shl, i8);
wrapping_shift_impl!(WrappingShl, wrapping_shl, i16);
wrapping_shift_impl!(WrappingShl, wrapping_shl, i32);
wrapping_shift_impl!(WrappingShl, wrapping_shl, i64);
wrapping_shift_impl!(WrappingShl, wrapping_shl, isize);
wrapping_shift_impl!(WrappingShl, wrapping_shl, i128);

/// Performs a right shift that does not panic.
pub trait WrappingShr: Sized + Shr<usize, Output = Self> {
    /// Panic-free bitwise shift-right; yields `self >> mask(rhs)`,
    /// where `mask` removes any high order bits of `rhs` that would
    /// cause the shift to exceed the bitwidth of the type.
    ///
    /// ```
    /// use num_traits::WrappingShr;
    ///
    /// let x: u16 = 0x8000;
    ///
    /// assert_eq!(WrappingShr::wrapping_shr(&x, 0),  0x8000);
    /// assert_eq!(WrappingShr::wrapping_shr(&x, 1),  0x4000);
    /// assert_eq!(WrappingShr::wrapping_shr(&x, 15), 0x0001);
    /// assert_eq!(WrappingShr::wrapping_shr(&x, 16), 0x8000);
    /// ```
    fn wrapping_shr(&self, rhs: u32) -> Self;
}

wrapping_shift_impl!(WrappingShr, wrapping_shr, u8);
wrapping_shift_impl!(WrappingShr, wrapping_shr, u16);
wrapping_shift_impl!(WrappingShr, wrapping_shr, u32);
wrapping_shift_impl!(WrappingShr, wrapping_shr, u64);
wrapping_shift_impl!(WrappingShr, wrapping_shr, usize);
wrapping_shift_impl!(WrappingShr, wrapping_shr, u128);

wrapping_shift_impl!(WrappingShr, wrapping_shr, i8);
wrapping_shift_impl!(WrappingShr, wrapping_shr, i16);
wrapping_shift_impl!(WrappingShr, wrapping_shr, i32);
wrapping_shift_impl!(WrappingShr, wrapping_shr, i64);
wrapping_shift_impl!(WrappingShr, wrapping_shr, isize);
wrapping_shift_impl!(WrappingShr, wrapping_shr, i128);

// Well this is a bit funny, but all the more appropriate.
impl<T: WrappingAdd> WrappingAdd for Wrapping<T>
where
    Wrapping<T>: Add<Output = Wrapping<T>>,
{
    fn wrapping_add(&self, v: &Self) -> Self {
        Wrapping(self.0.wrapping_add(&v.0))
    }
}
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))
    }
}
impl<T: WrappingNeg> WrappingNeg for Wrapping<T>
where
    Wrapping<T>: Neg<Output = Wrapping<T>>,
{
    fn wrapping_neg(&self) -> Self {
        Wrapping(self.0.wrapping_neg())
    }
}
impl<T: WrappingShl> WrappingShl for Wrapping<T>
where
    Wrapping<T>: Shl<usize, Output = Wrapping<T>>,
{
    fn wrapping_shl(&self, rhs: u32) -> Self {
        Wrapping(self.0.wrapping_shl(rhs))
    }
}
impl<T: WrappingShr> WrappingShr for Wrapping<T>
where
    Wrapping<T>: Shr<usize, Output = Wrapping<T>>,
{
    fn wrapping_shr(&self, rhs: u32) -> Self {
        Wrapping(self.0.wrapping_shr(rhs))
    }
}

#[test]
fn test_wrapping_traits() {
    fn wrapping_add<T: WrappingAdd>(a: T, b: T) -> T {
        a.wrapping_add(&b)
    }
    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)
    }
    fn wrapping_neg<T: WrappingNeg>(a: T) -> T {
        a.wrapping_neg()
    }
    fn wrapping_shl<T: WrappingShl>(a: T, b: u32) -> T {
        a.wrapping_shl(b)
    }
    fn wrapping_shr<T: WrappingShr>(a: T, b: u32) -> T {
        a.wrapping_shr(b)
    }
    assert_eq!(wrapping_add(255, 1), 0u8);
    assert_eq!(wrapping_sub(0, 1), 255u8);
    assert_eq!(wrapping_mul(255, 2), 254u8);
    assert_eq!(wrapping_neg(255), 1u8);
    assert_eq!(wrapping_shl(255, 8), 255u8);
    assert_eq!(wrapping_shr(255, 8), 255u8);
    assert_eq!(wrapping_add(255, 1), (Wrapping(255u8) + Wrapping(1u8)).0);
    assert_eq!(wrapping_sub(0, 1), (Wrapping(0u8) - Wrapping(1u8)).0);
    assert_eq!(wrapping_mul(255, 2), (Wrapping(255u8) * Wrapping(2u8)).0);
    assert_eq!(wrapping_neg(255), (-Wrapping(255u8)).0);
    assert_eq!(wrapping_shl(255, 8), (Wrapping(255u8) << 8).0);
    assert_eq!(wrapping_shr(255, 8), (Wrapping(255u8) >> 8).0);
}

#[test]
fn wrapping_is_wrappingadd() {
    fn require_wrappingadd<T: WrappingAdd>(_: &T) {}
    require_wrappingadd(&Wrapping(42));
}

#[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));
}

#[test]
fn wrapping_is_wrappingneg() {
    fn require_wrappingneg<T: WrappingNeg>(_: &T) {}
    require_wrappingneg(&Wrapping(42));
}

#[test]
fn wrapping_is_wrappingshl() {
    fn require_wrappingshl<T: WrappingShl>(_: &T) {}
    require_wrappingshl(&Wrapping(42));
}

#[test]
fn wrapping_is_wrappingshr() {
    fn require_wrappingshr<T: WrappingShr>(_: &T) {}
    require_wrappingshr(&Wrapping(42));
}

Coverage Report

Created: 2025-10-28 06:54

Line	Count	Source
1		use core::num::Wrapping;
2		use core::ops::{Add, Mul, Neg, Shl, Shr, Sub};
3
4		macro_rules! wrapping_impl {
5		($trait_name:ident, $method:ident, $t:ty) => {
6		impl $trait_name for $t {
7		#[inline]
8	0	fn $method(&self, v: &Self) -> Self {
9	0	<$t>::$method(self, v)
10	0	} Unexecuted instantiation: <u8 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <u16 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <u32 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <u64 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <usize as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <u128 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <i32 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <i64 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <isize as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <i128 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <i8 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <i16 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <i32 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <i64 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <isize as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <i128 as num_traits::ops::wrapping::WrappingAdd>::wrapping_add Unexecuted instantiation: <u8 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <u16 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <u32 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <u64 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <usize as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <u128 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <i8 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <i16 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <i32 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <i64 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <isize as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <i128 as num_traits::ops::wrapping::WrappingSub>::wrapping_sub Unexecuted instantiation: <u8 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <u16 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <u32 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <u64 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <usize as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <u128 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <i8 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul Unexecuted instantiation: <i16 as num_traits::ops::wrapping::WrappingMul>::wrapping_mul
11		}
12		};
13		($trait_name:ident, $method:ident, $t:ty, $rhs:ty) => {
14		impl $trait_name<$rhs> for $t {
15		#[inline]
16		fn $method(&self, v: &$rhs) -> Self {
17		<$t>::$method(self, v)
18		}
19		}
20		};
21		}
22
23		/// Performs addition that wraps around on overflow.
24		pub trait WrappingAdd: Sized + Add<Self, Output = Self> {
25		/// Wrapping (modular) addition. Computes `self + other`, wrapping around at the boundary of
26		/// the type.
27		fn wrapping_add(&self, v: &Self) -> Self;
28		}
29
30		wrapping_impl!(WrappingAdd, wrapping_add, u8);
31		wrapping_impl!(WrappingAdd, wrapping_add, u16);
32		wrapping_impl!(WrappingAdd, wrapping_add, u32);
33		wrapping_impl!(WrappingAdd, wrapping_add, u64);
34		wrapping_impl!(WrappingAdd, wrapping_add, usize);
35		wrapping_impl!(WrappingAdd, wrapping_add, u128);
36
37		wrapping_impl!(WrappingAdd, wrapping_add, i8);
38		wrapping_impl!(WrappingAdd, wrapping_add, i16);
39		wrapping_impl!(WrappingAdd, wrapping_add, i32);
40		wrapping_impl!(WrappingAdd, wrapping_add, i64);
41		wrapping_impl!(WrappingAdd, wrapping_add, isize);
42		wrapping_impl!(WrappingAdd, wrapping_add, i128);
43
44		/// Performs subtraction that wraps around on overflow.
45		pub trait WrappingSub: Sized + Sub<Self, Output = Self> {
46		/// Wrapping (modular) subtraction. Computes `self - other`, wrapping around at the boundary
47		/// of the type.
48		fn wrapping_sub(&self, v: &Self) -> Self;
49		}
50
51		wrapping_impl!(WrappingSub, wrapping_sub, u8);
52		wrapping_impl!(WrappingSub, wrapping_sub, u16);
53		wrapping_impl!(WrappingSub, wrapping_sub, u32);
54		wrapping_impl!(WrappingSub, wrapping_sub, u64);
55		wrapping_impl!(WrappingSub, wrapping_sub, usize);
56		wrapping_impl!(WrappingSub, wrapping_sub, u128);
57
58		wrapping_impl!(WrappingSub, wrapping_sub, i8);
59		wrapping_impl!(WrappingSub, wrapping_sub, i16);
60		wrapping_impl!(WrappingSub, wrapping_sub, i32);
61		wrapping_impl!(WrappingSub, wrapping_sub, i64);
62		wrapping_impl!(WrappingSub, wrapping_sub, isize);
63		wrapping_impl!(WrappingSub, wrapping_sub, i128);
64
65		/// Performs multiplication that wraps around on overflow.
66		pub trait WrappingMul: Sized + Mul<Self, Output = Self> {
67		/// Wrapping (modular) multiplication. Computes `self * other`, wrapping around at the boundary
68		/// of the type.
69		fn wrapping_mul(&self, v: &Self) -> Self;
70		}
71
72		wrapping_impl!(WrappingMul, wrapping_mul, u8);
73		wrapping_impl!(WrappingMul, wrapping_mul, u16);
74		wrapping_impl!(WrappingMul, wrapping_mul, u32);
75		wrapping_impl!(WrappingMul, wrapping_mul, u64);
76		wrapping_impl!(WrappingMul, wrapping_mul, usize);
77		wrapping_impl!(WrappingMul, wrapping_mul, u128);
78
79		wrapping_impl!(WrappingMul, wrapping_mul, i8);
80		wrapping_impl!(WrappingMul, wrapping_mul, i16);
81		wrapping_impl!(WrappingMul, wrapping_mul, i32);
82		wrapping_impl!(WrappingMul, wrapping_mul, i64);
83		wrapping_impl!(WrappingMul, wrapping_mul, isize);
84		wrapping_impl!(WrappingMul, wrapping_mul, i128);
85
86		macro_rules! wrapping_unary_impl {
87		($trait_name:ident, $method:ident, $t:ty) => {
88		impl $trait_name for $t {
89		#[inline]
90	0	fn $method(&self) -> $t {
91	0	<$t>::$method(*self)
92	0	} Unexecuted instantiation: <u8 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <u16 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <u32 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <u64 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <usize as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <u128 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <i8 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <i16 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <i32 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <i64 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <isize as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg Unexecuted instantiation: <i128 as num_traits::ops::wrapping::WrappingNeg>::wrapping_neg
93		}
94		};
95		}
96
97		/// Performs a negation that does not panic.
98		pub trait WrappingNeg: Sized {
99		/// Wrapping (modular) negation. Computes `-self`,
100		/// wrapping around at the boundary of the type.
101		///
102		/// Since unsigned types do not have negative equivalents
103		/// all applications of this function will wrap (except for `-0`).
104		/// For values smaller than the corresponding signed type's maximum
105		/// the result is the same as casting the corresponding signed value.
106		/// Any larger values are equivalent to `MAX + 1 - (val - MAX - 1)` where
107		/// `MAX` is the corresponding signed type's maximum.
108		///
109		/// ```
110		/// use num_traits::WrappingNeg;
111		///
112		/// assert_eq!(100i8.wrapping_neg(), -100);
113		/// assert_eq!((-100i8).wrapping_neg(), 100);
114		/// assert_eq!((-128i8).wrapping_neg(), -128); // wrapped!
115		/// ```
116		fn wrapping_neg(&self) -> Self;
117		}
118
119		wrapping_unary_impl!(WrappingNeg, wrapping_neg, u8);
120		wrapping_unary_impl!(WrappingNeg, wrapping_neg, u16);
121		wrapping_unary_impl!(WrappingNeg, wrapping_neg, u32);
122		wrapping_unary_impl!(WrappingNeg, wrapping_neg, u64);
123		wrapping_unary_impl!(WrappingNeg, wrapping_neg, usize);
124		wrapping_unary_impl!(WrappingNeg, wrapping_neg, u128);
125		wrapping_unary_impl!(WrappingNeg, wrapping_neg, i8);
126		wrapping_unary_impl!(WrappingNeg, wrapping_neg, i16);
127		wrapping_unary_impl!(WrappingNeg, wrapping_neg, i32);
128		wrapping_unary_impl!(WrappingNeg, wrapping_neg, i64);
129		wrapping_unary_impl!(WrappingNeg, wrapping_neg, isize);
130		wrapping_unary_impl!(WrappingNeg, wrapping_neg, i128);
131
132		macro_rules! wrapping_shift_impl {
133		($trait_name:ident, $method:ident, $t:ty) => {
134		impl $trait_name for $t {
135		#[inline]
136	0	fn $method(&self, rhs: u32) -> $t {
137	0	<$t>::$method(*self, rhs)
138	0	} Unexecuted instantiation: <isize as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <i128 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <u8 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <u16 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <u32 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <u64 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <usize as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <u128 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <i8 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <i16 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <i32 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <i64 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <isize as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <i128 as num_traits::ops::wrapping::WrappingShr>::wrapping_shr Unexecuted instantiation: <u8 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <u16 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <u32 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <u64 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <usize as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <u128 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <i8 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <i16 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <i32 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl Unexecuted instantiation: <i64 as num_traits::ops::wrapping::WrappingShl>::wrapping_shl
139		}
140		};
141		}
142
143		/// Performs a left shift that does not panic.
144		pub trait WrappingShl: Sized + Shl<usize, Output = Self> {
145		/// Panic-free bitwise shift-left; yields `self << mask(rhs)`,
146		/// where `mask` removes any high order bits of `rhs` that would
147		/// cause the shift to exceed the bitwidth of the type.
148		///
149		/// ```
150		/// use num_traits::WrappingShl;
151		///
152		/// let x: u16 = 0x0001;
153		///
154		/// assert_eq!(WrappingShl::wrapping_shl(&x, 0), 0x0001);
155		/// assert_eq!(WrappingShl::wrapping_shl(&x, 1), 0x0002);
156		/// assert_eq!(WrappingShl::wrapping_shl(&x, 15), 0x8000);
157		/// assert_eq!(WrappingShl::wrapping_shl(&x, 16), 0x0001);
158		/// ```
159		fn wrapping_shl(&self, rhs: u32) -> Self;
160		}
161
162		wrapping_shift_impl!(WrappingShl, wrapping_shl, u8);
163		wrapping_shift_impl!(WrappingShl, wrapping_shl, u16);
164		wrapping_shift_impl!(WrappingShl, wrapping_shl, u32);
165		wrapping_shift_impl!(WrappingShl, wrapping_shl, u64);
166		wrapping_shift_impl!(WrappingShl, wrapping_shl, usize);
167		wrapping_shift_impl!(WrappingShl, wrapping_shl, u128);
168
169		wrapping_shift_impl!(WrappingShl, wrapping_shl, i8);
170		wrapping_shift_impl!(WrappingShl, wrapping_shl, i16);
171		wrapping_shift_impl!(WrappingShl, wrapping_shl, i32);
172		wrapping_shift_impl!(WrappingShl, wrapping_shl, i64);
173		wrapping_shift_impl!(WrappingShl, wrapping_shl, isize);
174		wrapping_shift_impl!(WrappingShl, wrapping_shl, i128);
175
176		/// Performs a right shift that does not panic.
177		pub trait WrappingShr: Sized + Shr<usize, Output = Self> {
178		/// Panic-free bitwise shift-right; yields `self >> mask(rhs)`,
179		/// where `mask` removes any high order bits of `rhs` that would
180		/// cause the shift to exceed the bitwidth of the type.
181		///
182		/// ```
183		/// use num_traits::WrappingShr;
184		///
185		/// let x: u16 = 0x8000;
186		///
187		/// assert_eq!(WrappingShr::wrapping_shr(&x, 0), 0x8000);
188		/// assert_eq!(WrappingShr::wrapping_shr(&x, 1), 0x4000);
189		/// assert_eq!(WrappingShr::wrapping_shr(&x, 15), 0x0001);
190		/// assert_eq!(WrappingShr::wrapping_shr(&x, 16), 0x8000);
191		/// ```
192		fn wrapping_shr(&self, rhs: u32) -> Self;
193		}
194
195		wrapping_shift_impl!(WrappingShr, wrapping_shr, u8);
196		wrapping_shift_impl!(WrappingShr, wrapping_shr, u16);
197		wrapping_shift_impl!(WrappingShr, wrapping_shr, u32);
198		wrapping_shift_impl!(WrappingShr, wrapping_shr, u64);
199		wrapping_shift_impl!(WrappingShr, wrapping_shr, usize);
200		wrapping_shift_impl!(WrappingShr, wrapping_shr, u128);
201
202		wrapping_shift_impl!(WrappingShr, wrapping_shr, i8);
203		wrapping_shift_impl!(WrappingShr, wrapping_shr, i16);
204		wrapping_shift_impl!(WrappingShr, wrapping_shr, i32);
205		wrapping_shift_impl!(WrappingShr, wrapping_shr, i64);
206		wrapping_shift_impl!(WrappingShr, wrapping_shr, isize);
207		wrapping_shift_impl!(WrappingShr, wrapping_shr, i128);
208
209		// Well this is a bit funny, but all the more appropriate.
210		impl<T: WrappingAdd> WrappingAdd for Wrapping<T>
211		where
212		Wrapping<T>: Add<Output = Wrapping<T>>,
213		{
214	0	fn wrapping_add(&self, v: &Self) -> Self {
215	0	Wrapping(self.0.wrapping_add(&v.0))
216	0	}
217		}
218		impl<T: WrappingSub> WrappingSub for Wrapping<T>
219		where
220		Wrapping<T>: Sub<Output = Wrapping<T>>,
221		{
222	0	fn wrapping_sub(&self, v: &Self) -> Self {
223	0	Wrapping(self.0.wrapping_sub(&v.0))
224	0	}
225		}
226		impl<T: WrappingMul> WrappingMul for Wrapping<T>
227		where
228		Wrapping<T>: Mul<Output = Wrapping<T>>,
229		{
230	0	fn wrapping_mul(&self, v: &Self) -> Self {
231	0	Wrapping(self.0.wrapping_mul(&v.0))
232	0	}
233		}
234		impl<T: WrappingNeg> WrappingNeg for Wrapping<T>
235		where
236		Wrapping<T>: Neg<Output = Wrapping<T>>,
237		{
238	0	fn wrapping_neg(&self) -> Self {
239	0	Wrapping(self.0.wrapping_neg())
240	0	}
241		}
242		impl<T: WrappingShl> WrappingShl for Wrapping<T>
243		where
244		Wrapping<T>: Shl<usize, Output = Wrapping<T>>,
245		{
246	0	fn wrapping_shl(&self, rhs: u32) -> Self {
247	0	Wrapping(self.0.wrapping_shl(rhs))
248	0	}
249		}
250		impl<T: WrappingShr> WrappingShr for Wrapping<T>
251		where
252		Wrapping<T>: Shr<usize, Output = Wrapping<T>>,
253		{
254	0	fn wrapping_shr(&self, rhs: u32) -> Self {
255	0	Wrapping(self.0.wrapping_shr(rhs))
256	0	}
257		}
258
259		#[test]
260		fn test_wrapping_traits() {
261		fn wrapping_add<T: WrappingAdd>(a: T, b: T) -> T {
262		a.wrapping_add(&b)
263		}
264		fn wrapping_sub<T: WrappingSub>(a: T, b: T) -> T {
265		a.wrapping_sub(&b)
266		}
267		fn wrapping_mul<T: WrappingMul>(a: T, b: T) -> T {
268		a.wrapping_mul(&b)
269		}
270		fn wrapping_neg<T: WrappingNeg>(a: T) -> T {
271		a.wrapping_neg()
272		}
273		fn wrapping_shl<T: WrappingShl>(a: T, b: u32) -> T {
274		a.wrapping_shl(b)
275		}
276		fn wrapping_shr<T: WrappingShr>(a: T, b: u32) -> T {
277		a.wrapping_shr(b)
278		}
279		assert_eq!(wrapping_add(255, 1), 0u8);
280		assert_eq!(wrapping_sub(0, 1), 255u8);
281		assert_eq!(wrapping_mul(255, 2), 254u8);
282		assert_eq!(wrapping_neg(255), 1u8);
283		assert_eq!(wrapping_shl(255, 8), 255u8);
284		assert_eq!(wrapping_shr(255, 8), 255u8);
285		assert_eq!(wrapping_add(255, 1), (Wrapping(255u8) + Wrapping(1u8)).0);
286		assert_eq!(wrapping_sub(0, 1), (Wrapping(0u8) - Wrapping(1u8)).0);
287		assert_eq!(wrapping_mul(255, 2), (Wrapping(255u8) * Wrapping(2u8)).0);
288		assert_eq!(wrapping_neg(255), (-Wrapping(255u8)).0);
289		assert_eq!(wrapping_shl(255, 8), (Wrapping(255u8) << 8).0);
290		assert_eq!(wrapping_shr(255, 8), (Wrapping(255u8) >> 8).0);
291		}
292
293		#[test]
294		fn wrapping_is_wrappingadd() {
295		fn require_wrappingadd<T: WrappingAdd>(_: &T) {}
296		require_wrappingadd(&Wrapping(42));
297		}
298
299		#[test]
300		fn wrapping_is_wrappingsub() {
301		fn require_wrappingsub<T: WrappingSub>(_: &T) {}
302		require_wrappingsub(&Wrapping(42));
303		}
304
305		#[test]
306		fn wrapping_is_wrappingmul() {
307		fn require_wrappingmul<T: WrappingMul>(_: &T) {}
308		require_wrappingmul(&Wrapping(42));
309		}
310
311		#[test]
312		fn wrapping_is_wrappingneg() {
313		fn require_wrappingneg<T: WrappingNeg>(_: &T) {}
314		require_wrappingneg(&Wrapping(42));
315		}
316
317		#[test]
318		fn wrapping_is_wrappingshl() {
319		fn require_wrappingshl<T: WrappingShl>(_: &T) {}
320		require_wrappingshl(&Wrapping(42));
321		}
322
323		#[test]
324		fn wrapping_is_wrappingshr() {
325		fn require_wrappingshr<T: WrappingShr>(_: &T) {}
326		require_wrappingshr(&Wrapping(42));
327		}