1.0.0[−][src]Trait boolean_enums::lstd::ops::Add
The addition operator +
.
Note that RHS
is Self
by default, but this is not mandatory. For
example, std::time::SystemTime
implements Add<Duration>
, which permits
operations of the form SystemTime = SystemTime + Duration
.
Examples
Add
able points
use std::ops::Add; #[derive(Debug, PartialEq)] struct Point { x: i32, y: i32, } impl Add for Point { type Output = Point; fn add(self, other: Point) -> Point { Point { x: self.x + other.x, y: self.y + other.y, } } } assert_eq!(Point { x: 1, y: 0 } + Point { x: 2, y: 3 }, Point { x: 3, y: 3 });
Implementing Add
with generics
Here is an example of the same Point
struct implementing the Add
trait
using generics.
use std::ops::Add; #[derive(Debug, PartialEq)] struct Point<T> { x: T, y: T, } // Notice that the implementation uses the associated type `Output`. impl<T: Add<Output=T>> Add for Point<T> { type Output = Point<T>; fn add(self, other: Point<T>) -> Point<T> { Point { x: self.x + other.x, y: self.y + other.y, } } } assert_eq!(Point { x: 1, y: 0 } + Point { x: 2, y: 3 }, Point { x: 3, y: 3 });
Associated Types
type Output
The resulting type after applying the +
operator.
Required methods
Loading content...Implementations on Foreign Types
impl<'a> Add<f32> for &'a f32
[src]
impl<'a> Add<f32> for &'a f32
impl<'a> Add<&'a i32> for i32
[src]
impl<'a> Add<&'a i32> for i32
type Output = <i32 as Add<i32>>::Output
fn add(self, other: &'a i32) -> <i32 as Add<i32>>::Output | [src] |
impl<'a, 'b> Add<&'a u16> for &'b u16
[src]
impl<'a, 'b> Add<&'a u16> for &'b u16
type Output = <u16 as Add<u16>>::Output
fn add(self, other: &'a u16) -> <u16 as Add<u16>>::Output | [src] |
impl<'a> Add<i32> for &'a i32
[src]
impl<'a> Add<i32> for &'a i32
impl<'a> Add<isize> for &'a isize
[src]
impl<'a> Add<isize> for &'a isize
type Output = <isize as Add<isize>>::Output
fn add(self, other: isize) -> <isize as Add<isize>>::Output | [src] |
impl<'a> Add<&'a u16> for u16
[src]
impl<'a> Add<&'a u16> for u16
type Output = <u16 as Add<u16>>::Output
fn add(self, other: &'a u16) -> <u16 as Add<u16>>::Output | [src] |
impl<'a, 'b> Add<&'a f32> for &'b f32
[src]
impl<'a, 'b> Add<&'a f32> for &'b f32
type Output = <f32 as Add<f32>>::Output
fn add(self, other: &'a f32) -> <f32 as Add<f32>>::Output | [src] |
impl Add<u32> for u32
[src]
impl Add<u32> for u32
impl Add<u16> for u16
[src]
impl Add<u16> for u16
impl Add<i64> for i64
[src]
impl Add<i64> for i64
impl Add<f32> for f32
[src]
impl Add<f32> for f32
impl<'a, 'b> Add<&'a i128> for &'b i128
[src]
impl<'a, 'b> Add<&'a i128> for &'b i128
type Output = <i128 as Add<i128>>::Output
fn add(self, other: &'a i128) -> <i128 as Add<i128>>::Output | [src] |
impl<'a, 'b> Add<&'a i16> for &'b i16
[src]
impl<'a, 'b> Add<&'a i16> for &'b i16
type Output = <i16 as Add<i16>>::Output
fn add(self, other: &'a i16) -> <i16 as Add<i16>>::Output | [src] |
impl Add<i32> for i32
[src]
impl Add<i32> for i32
impl<'a> Add<i128> for &'a i128
[src]
impl<'a> Add<i128> for &'a i128
type Output = <i128 as Add<i128>>::Output
fn add(self, other: i128) -> <i128 as Add<i128>>::Output | [src] |
impl<'a, 'b> Add<&'a i64> for &'b i64
[src]
impl<'a, 'b> Add<&'a i64> for &'b i64
type Output = <i64 as Add<i64>>::Output
fn add(self, other: &'a i64) -> <i64 as Add<i64>>::Output | [src] |
impl<'a> Add<i16> for &'a i16
[src]
impl<'a> Add<i16> for &'a i16
impl<'a> Add<&'a u8> for u8
[src]
impl<'a> Add<&'a u8> for u8
impl<'a> Add<&'a u32> for u32
[src]
impl<'a> Add<&'a u32> for u32
type Output = <u32 as Add<u32>>::Output
fn add(self, other: &'a u32) -> <u32 as Add<u32>>::Output | [src] |
impl<'a, 'b> Add<&'a i32> for &'b i32
[src]
impl<'a, 'b> Add<&'a i32> for &'b i32
type Output = <i32 as Add<i32>>::Output
fn add(self, other: &'a i32) -> <i32 as Add<i32>>::Output | [src] |
impl<'a, 'b> Add<&'a u128> for &'b u128
[src]
impl<'a, 'b> Add<&'a u128> for &'b u128
type Output = <u128 as Add<u128>>::Output
fn add(self, other: &'a u128) -> <u128 as Add<u128>>::Output | [src] |
impl<'a, 'b> Add<&'a u64> for &'b u64
[src]
impl<'a, 'b> Add<&'a u64> for &'b u64
type Output = <u64 as Add<u64>>::Output
fn add(self, other: &'a u64) -> <u64 as Add<u64>>::Output | [src] |
impl<'a, 'b> Add<&'a u8> for &'b u8
[src]
impl<'a, 'b> Add<&'a u8> for &'b u8
impl Add<i16> for i16
[src]
impl Add<i16> for i16
impl Add<u64> for u64
[src]
impl Add<u64> for u64
impl<'a> Add<u16> for &'a u16
[src]
impl<'a> Add<u16> for &'a u16
impl<'a> Add<&'a u128> for u128
[src]
impl<'a> Add<&'a u128> for u128
type Output = <u128 as Add<u128>>::Output
fn add(self, other: &'a u128) -> <u128 as Add<u128>>::Output | [src] |
impl<'a, 'b> Add<&'a f64> for &'b f64
[src]
impl<'a, 'b> Add<&'a f64> for &'b f64
type Output = <f64 as Add<f64>>::Output
fn add(self, other: &'a f64) -> <f64 as Add<f64>>::Output | [src] |
impl Add<i8> for i8
[src]
impl Add<i8> for i8
impl Add<usize> for usize
[src]
impl Add<usize> for usize
impl<'a> Add<u32> for &'a u32
[src]
impl<'a> Add<u32> for &'a u32
impl<'a> Add<&'a f64> for f64
[src]
impl<'a> Add<&'a f64> for f64
type Output = <f64 as Add<f64>>::Output
fn add(self, other: &'a f64) -> <f64 as Add<f64>>::Output | [src] |
impl<'a> Add<i8> for &'a i8
[src]
impl<'a> Add<i8> for &'a i8
impl<'a, 'b> Add<&'a i8> for &'b i8
[src]
impl<'a, 'b> Add<&'a i8> for &'b i8
impl Add<i128> for i128
[src]
impl Add<i128> for i128
impl<'a> Add<u128> for &'a u128
[src]
impl<'a> Add<u128> for &'a u128
type Output = <u128 as Add<u128>>::Output
fn add(self, other: u128) -> <u128 as Add<u128>>::Output | [src] |
impl<'a> Add<&'a u64> for u64
[src]
impl<'a> Add<&'a u64> for u64
type Output = <u64 as Add<u64>>::Output
fn add(self, other: &'a u64) -> <u64 as Add<u64>>::Output | [src] |
impl<'a> Add<usize> for &'a usize
[src]
impl<'a> Add<usize> for &'a usize
type Output = <usize as Add<usize>>::Output
fn add(self, other: usize) -> <usize as Add<usize>>::Output | [src] |
impl<'a> Add<&'a i64> for i64
[src]
impl<'a> Add<&'a i64> for i64
type Output = <i64 as Add<i64>>::Output
fn add(self, other: &'a i64) -> <i64 as Add<i64>>::Output | [src] |
impl Add<u8> for u8
[src]
impl Add<u8> for u8
impl<'a> Add<u64> for &'a u64
[src]
impl<'a> Add<u64> for &'a u64
impl<'a, 'b> Add<&'a u32> for &'b u32
[src]
impl<'a, 'b> Add<&'a u32> for &'b u32
type Output = <u32 as Add<u32>>::Output
fn add(self, other: &'a u32) -> <u32 as Add<u32>>::Output | [src] |
impl<'a> Add<&'a isize> for isize
[src]
impl<'a> Add<&'a isize> for isize
type Output = <isize as Add<isize>>::Output
fn add(self, other: &'a isize) -> <isize as Add<isize>>::Output | [src] |
impl<'a, 'b> Add<&'a isize> for &'b isize
[src]
impl<'a, 'b> Add<&'a isize> for &'b isize
type Output = <isize as Add<isize>>::Output
fn add(self, other: &'a isize) -> <isize as Add<isize>>::Output | [src] |
impl<'a> Add<f64> for &'a f64
[src]
impl<'a> Add<f64> for &'a f64
impl Add<u128> for u128
[src]
impl Add<u128> for u128
impl Add<f64> for f64
[src]
impl Add<f64> for f64
impl<'a> Add<&'a i16> for i16
[src]
impl<'a> Add<&'a i16> for i16
type Output = <i16 as Add<i16>>::Output
fn add(self, other: &'a i16) -> <i16 as Add<i16>>::Output | [src] |
impl<'a> Add<i64> for &'a i64
[src]
impl<'a> Add<i64> for &'a i64
impl<'a> Add<&'a i128> for i128
[src]
impl<'a> Add<&'a i128> for i128
type Output = <i128 as Add<i128>>::Output
fn add(self, other: &'a i128) -> <i128 as Add<i128>>::Output | [src] |
impl<'a> Add<&'a i8> for i8
[src]
impl<'a> Add<&'a i8> for i8
impl<'a> Add<&'a f32> for f32
[src]
impl<'a> Add<&'a f32> for f32
type Output = <f32 as Add<f32>>::Output
fn add(self, other: &'a f32) -> <f32 as Add<f32>>::Output | [src] |
impl<'a> Add<&'a usize> for usize
[src]
impl<'a> Add<&'a usize> for usize
type Output = <usize as Add<usize>>::Output
fn add(self, other: &'a usize) -> <usize as Add<usize>>::Output | [src] |
impl<'a, 'b> Add<&'a usize> for &'b usize
[src]
impl<'a, 'b> Add<&'a usize> for &'b usize
type Output = <usize as Add<usize>>::Output
fn add(self, other: &'a usize) -> <usize as Add<usize>>::Output | [src] |
impl Add<isize> for isize
[src]
impl Add<isize> for isize
impl<'a> Add<u8> for &'a u8
[src]
Loading content...
impl<'a> Add<u8> for &'a u8
Implementors
impl Add<Wrapping<i128>> for Wrapping<i128>
[src]
impl Add<Wrapping<i128>> for Wrapping<i128>
impl Add<Wrapping<i16>> for Wrapping<i16>
[src]
impl Add<Wrapping<i16>> for Wrapping<i16>
impl Add<Wrapping<i32>> for Wrapping<i32>
[src]
impl Add<Wrapping<i32>> for Wrapping<i32>
impl Add<Wrapping<i64>> for Wrapping<i64>
[src]
impl Add<Wrapping<i64>> for Wrapping<i64>
impl Add<Wrapping<i8>> for Wrapping<i8>
[src]
impl Add<Wrapping<i8>> for Wrapping<i8>
impl Add<Wrapping<isize>> for Wrapping<isize>
[src]
impl Add<Wrapping<isize>> for Wrapping<isize>
impl Add<Wrapping<u128>> for Wrapping<u128>
[src]
impl Add<Wrapping<u128>> for Wrapping<u128>
impl Add<Wrapping<u16>> for Wrapping<u16>
[src]
impl Add<Wrapping<u16>> for Wrapping<u16>
impl Add<Wrapping<u32>> for Wrapping<u32>
[src]
impl Add<Wrapping<u32>> for Wrapping<u32>
impl Add<Wrapping<u64>> for Wrapping<u64>
[src]
impl Add<Wrapping<u64>> for Wrapping<u64>
impl Add<Wrapping<u8>> for Wrapping<u8>
[src]
impl Add<Wrapping<u8>> for Wrapping<u8>
impl Add<Wrapping<usize>> for Wrapping<usize>
[src]
impl Add<Wrapping<usize>> for Wrapping<usize>
impl Add<Duration> for Duration
[src]
impl Add<Duration> for Duration
impl Add<Duration> for Instant
[src]
impl Add<Duration> for Instant
type Output = Instant
fn add(self, other: Duration) -> Instant | [src] |
Panics
This function may panic if the resulting point in time cannot be represented by the
underlying data structure. See checked_add
for a version without panic.
impl Add<Duration> for SystemTime
[src]
impl Add<Duration> for SystemTime
type Output = SystemTime
fn add(self, dur: Duration) -> SystemTime | [src] |
Panics
This function may panic if the resulting point in time cannot be represented by the
underlying data structure. See checked_add
for a version without panic.
impl<'a> Add<&'a str> for Cow<'a, str>
[src]
impl<'a> Add<&'a str> for Cow<'a, str>
impl<'a> Add<&'a str> for String
[src]
impl<'a> Add<&'a str> for String
Implements the +
operator for concatenating two strings.
This consumes the String
on the left-hand side and re-uses its buffer (growing it if
necessary). This is done to avoid allocating a new String
and copying the entire contents on
every operation, which would lead to O(n^2)
running time when building an n
-byte string by
repeated concatenation.
The string on the right-hand side is only borrowed; its contents are copied into the returned
String
.
Examples
Concatenating two String
s takes the first by value and borrows the second:
let a = String::from("hello"); let b = String::from(" world"); let c = a + &b; // `a` is moved and can no longer be used here.
If you want to keep using the first String
, you can clone it and append to the clone instead:
let a = String::from("hello"); let b = String::from(" world"); let c = a.clone() + &b; // `a` is still valid here.
Concatenating &str
slices can be done by converting the first to a String
:
let a = "hello"; let b = " world"; let c = a.to_string() + b;
impl<'a> Add<&'a Wrapping<i128>> for Wrapping<i128>
[src]
impl<'a> Add<&'a Wrapping<i128>> for Wrapping<i128>
type Output = <Wrapping<i128> as Add<Wrapping<i128>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<i16>> for Wrapping<i16>
[src]
impl<'a> Add<&'a Wrapping<i16>> for Wrapping<i16>
type Output = <Wrapping<i16> as Add<Wrapping<i16>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<i32>> for Wrapping<i32>
[src]
impl<'a> Add<&'a Wrapping<i32>> for Wrapping<i32>
type Output = <Wrapping<i32> as Add<Wrapping<i32>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<i64>> for Wrapping<i64>
[src]
impl<'a> Add<&'a Wrapping<i64>> for Wrapping<i64>
type Output = <Wrapping<i64> as Add<Wrapping<i64>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<i8>> for Wrapping<i8>
[src]
impl<'a> Add<&'a Wrapping<i8>> for Wrapping<i8>
type Output = <Wrapping<i8> as Add<Wrapping<i8>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<isize>> for Wrapping<isize>
[src]
impl<'a> Add<&'a Wrapping<isize>> for Wrapping<isize>
type Output = <Wrapping<isize> as Add<Wrapping<isize>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<u128>> for Wrapping<u128>
[src]
impl<'a> Add<&'a Wrapping<u128>> for Wrapping<u128>
type Output = <Wrapping<u128> as Add<Wrapping<u128>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<u16>> for Wrapping<u16>
[src]
impl<'a> Add<&'a Wrapping<u16>> for Wrapping<u16>
type Output = <Wrapping<u16> as Add<Wrapping<u16>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<u32>> for Wrapping<u32>
[src]
impl<'a> Add<&'a Wrapping<u32>> for Wrapping<u32>
type Output = <Wrapping<u32> as Add<Wrapping<u32>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<u64>> for Wrapping<u64>
[src]
impl<'a> Add<&'a Wrapping<u64>> for Wrapping<u64>
type Output = <Wrapping<u64> as Add<Wrapping<u64>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<u8>> for Wrapping<u8>
[src]
impl<'a> Add<&'a Wrapping<u8>> for Wrapping<u8>
type Output = <Wrapping<u8> as Add<Wrapping<u8>>>::Output
fn add( | [src] |
impl<'a> Add<&'a Wrapping<usize>> for Wrapping<usize>
[src]
impl<'a> Add<&'a Wrapping<usize>> for Wrapping<usize>
type Output = <Wrapping<usize> as Add<Wrapping<usize>>>::Output
fn add( | [src] |
impl<'a> Add<Cow<'a, str>> for Cow<'a, str>
[src]
impl<'a> Add<Cow<'a, str>> for Cow<'a, str>
type Output = Cow<'a, str>
fn add(self, rhs: Cow<'a, str>) -> <Cow<'a, str> as Add<Cow<'a, str>>>::Output | [src] |
impl<'a> Add<Wrapping<i128>> for &'a Wrapping<i128>
[src]
impl<'a> Add<Wrapping<i128>> for &'a Wrapping<i128>
type Output = <Wrapping<i128> as Add<Wrapping<i128>>>::Output
fn add( | [src] |
impl<'a> Add<Wrapping<i16>> for &'a Wrapping<i16>
[src]
impl<'a> Add<Wrapping<i16>> for &'a Wrapping<i16>
type Output = <Wrapping<i16> as Add<Wrapping<i16>>>::Output
fn add( | [src] |
impl<'a> Add<Wrapping<i32>> for &'a Wrapping<i32>
[src]
impl<'a> Add<Wrapping<i32>> for &'a Wrapping<i32>
type Output = <Wrapping<i32> as Add<Wrapping<i32>>>::Output
fn add( | [src] |
impl<'a> Add<Wrapping<i64>> for &'a Wrapping<i64>
[src]
impl<'a> Add<Wrapping<i64>> for &'a Wrapping<i64>
type Output = <Wrapping<i64> as Add<Wrapping<i64>>>::Output
fn add( | [src] |
impl<'a> Add<Wrapping<i8>> for &'a Wrapping<i8>
[src]
impl<'a> Add<Wrapping<i8>> for &'a Wrapping<i8>
type Output = <Wrapping<i8> as Add<Wrapping<i8>>>::Output
fn add(self, other: Wrapping<i8>) -> <Wrapping<i8> as Add<Wrapping<i8>>>::Output | [src] |
impl<'a> Add<Wrapping<isize>> for &'a Wrapping<isize>
[src]
impl<'a> Add<Wrapping<isize>> for &'a Wrapping<isize>
type Output = <Wrapping<isize> as Add<Wrapping<isize>>>::Output
fn add( | [src] |
impl<'a> Add<Wrapping<u128>> for &'a Wrapping<u128>
[src]
impl<'a> Add<Wrapping<u128>> for &'a Wrapping<u128>
type Output = <Wrapping<u128> as Add<Wrapping<u128>>>::Output
fn add( | [src] |
impl<'a> Add<Wrapping<u16>> for &'a Wrapping<u16>
[src]
impl<'a> Add<Wrapping<u16>> for &'a Wrapping<u16>
type Output = <Wrapping<u16> as Add<Wrapping<u16>>>::Output
fn add( | [src] |
impl<'a> Add<Wrapping<u32>> for &'a Wrapping<u32>
[src]
impl<'a> Add<Wrapping<u32>> for &'a Wrapping<u32>
type Output = <Wrapping<u32> as Add<Wrapping<u32>>>::Output
fn add( | [src] |
impl<'a> Add<Wrapping<u64>> for &'a Wrapping<u64>
[src]
impl<'a> Add<Wrapping<u64>> for &'a Wrapping<u64>
type Output = <Wrapping<u64> as Add<Wrapping<u64>>>::Output
fn add( | [src] |
impl<'a> Add<Wrapping<u8>> for &'a Wrapping<u8>
[src]
impl<'a> Add<Wrapping<u8>> for &'a Wrapping<u8>
type Output = <Wrapping<u8> as Add<Wrapping<u8>>>::Output
fn add(self, other: Wrapping<u8>) -> <Wrapping<u8> as Add<Wrapping<u8>>>::Output | [src] |
impl<'a> Add<Wrapping<usize>> for &'a Wrapping<usize>
[src]
impl<'a> Add<Wrapping<usize>> for &'a Wrapping<usize>
type Output = <Wrapping<usize> as Add<Wrapping<usize>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<i128>> for &'b Wrapping<i128>
[src]
impl<'a, 'b> Add<&'a Wrapping<i128>> for &'b Wrapping<i128>
type Output = <Wrapping<i128> as Add<Wrapping<i128>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<i16>> for &'b Wrapping<i16>
[src]
impl<'a, 'b> Add<&'a Wrapping<i16>> for &'b Wrapping<i16>
type Output = <Wrapping<i16> as Add<Wrapping<i16>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<i32>> for &'b Wrapping<i32>
[src]
impl<'a, 'b> Add<&'a Wrapping<i32>> for &'b Wrapping<i32>
type Output = <Wrapping<i32> as Add<Wrapping<i32>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<i64>> for &'b Wrapping<i64>
[src]
impl<'a, 'b> Add<&'a Wrapping<i64>> for &'b Wrapping<i64>
type Output = <Wrapping<i64> as Add<Wrapping<i64>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<i8>> for &'b Wrapping<i8>
[src]
impl<'a, 'b> Add<&'a Wrapping<i8>> for &'b Wrapping<i8>
type Output = <Wrapping<i8> as Add<Wrapping<i8>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<isize>> for &'b Wrapping<isize>
[src]
impl<'a, 'b> Add<&'a Wrapping<isize>> for &'b Wrapping<isize>
type Output = <Wrapping<isize> as Add<Wrapping<isize>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<u128>> for &'b Wrapping<u128>
[src]
impl<'a, 'b> Add<&'a Wrapping<u128>> for &'b Wrapping<u128>
type Output = <Wrapping<u128> as Add<Wrapping<u128>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<u16>> for &'b Wrapping<u16>
[src]
impl<'a, 'b> Add<&'a Wrapping<u16>> for &'b Wrapping<u16>
type Output = <Wrapping<u16> as Add<Wrapping<u16>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<u32>> for &'b Wrapping<u32>
[src]
impl<'a, 'b> Add<&'a Wrapping<u32>> for &'b Wrapping<u32>
type Output = <Wrapping<u32> as Add<Wrapping<u32>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<u64>> for &'b Wrapping<u64>
[src]
impl<'a, 'b> Add<&'a Wrapping<u64>> for &'b Wrapping<u64>
type Output = <Wrapping<u64> as Add<Wrapping<u64>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<u8>> for &'b Wrapping<u8>
[src]
impl<'a, 'b> Add<&'a Wrapping<u8>> for &'b Wrapping<u8>
type Output = <Wrapping<u8> as Add<Wrapping<u8>>>::Output
fn add( | [src] |
impl<'a, 'b> Add<&'a Wrapping<usize>> for &'b Wrapping<usize>
[src]
impl<'a, 'b> Add<&'a Wrapping<usize>> for &'b Wrapping<usize>