# Trait std::ops::Add

1.0.0 · source ·

    pub trait Add<Rhs = Self> {
        type Output;

        // Required method
        fn add(self, rhs: Rhs) -> Self::Output;
    }

Expand description

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, Copy, Clone, PartialEq)]
    struct Point {
        x: i32,
        y: i32,
    }

    impl Add for Point {
        type Output = Self;

        fn add(self, other: Self) -> Self {
            Self {
                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 });

Run

### 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, Copy, Clone, 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 = Self;

        fn add(self, other: Self) -> Self::Output {
            Self {
                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 });

Run

## Required Associated Types§

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#### type Output

The resulting type after applying the `+` operator.

## Required Methods§

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#### fn add(self, rhs: Rhs) -> Self::Output

Performs the `+` operation.

##### Example

    assert_eq!(12 + 1, 13);

Run

## Implementors§

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### impl Add for f32

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#### type Output = f32

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### impl Add for f64

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#### type Output = f64

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### impl Add for i8

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#### type Output = i8

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### impl Add for i16

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#### type Output = i16

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### impl Add for i32

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#### type Output = i32

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### impl Add for i64

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#### type Output = i64

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### impl Add for i128

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#### type Output = i128

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### impl Add for isize

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#### type Output = isize

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### impl Add for u8

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#### type Output = u8

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### impl Add for u16

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#### type Output = u16

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### impl Add for u32

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#### type Output = u32

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### impl Add for u64

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#### type Output = u64

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### impl Add for u128

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#### type Output = u128

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### impl Add for usize

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#### type Output = usize

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### impl Add for Assume

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#### type Output = Assume

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### impl Add for Saturating<i8>

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#### type Output = Saturating<i8>

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### impl Add for Saturating<i16>

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#### type Output = Saturating<i16>

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### impl Add for Saturating<i32>

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#### type Output = Saturating<i32>

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### impl Add for Saturating<i64>

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#### type Output = Saturating<i64>

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### impl Add for Saturating<i128>

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#### type Output = Saturating<i128>

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### impl Add for Saturating<isize>

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#### type Output = Saturating<isize>

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### impl Add for Saturating<u8>

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#### type Output = Saturating<u8>

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### impl Add for Saturating<u16>

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#### type Output = Saturating<u16>

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### impl Add for Saturating<u32>

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#### type Output = Saturating<u32>

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### impl Add for Saturating<u64>

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#### type Output = Saturating<u64>

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### impl Add for Saturating<u128>

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#### type Output = Saturating<u128>

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### impl Add for Saturating<usize>

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#### type Output = Saturating<usize>

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### impl Add for Wrapping<i8>

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#### type Output = Wrapping<i8>

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### impl Add for Wrapping<i16>

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#### type Output = Wrapping<i16>

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### impl Add for Wrapping<i32>

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#### type Output = Wrapping<i32>

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### impl Add for Wrapping<i64>

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#### type Output = Wrapping<i64>

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### impl Add for Wrapping<i128>

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#### type Output = Wrapping<i128>

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### impl Add for Wrapping<isize>

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#### type Output = Wrapping<isize>

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### impl Add for Wrapping<u8>

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#### type Output = Wrapping<u8>

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### impl Add for Wrapping<u16>

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#### type Output = Wrapping<u16>

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### impl Add for Wrapping<u32>

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#### type Output = Wrapping<u32>

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### impl Add for Wrapping<u64>

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#### type Output = Wrapping<u64>

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### impl Add for Wrapping<u128>

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#### type Output = Wrapping<u128>

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### impl Add for Wrapping<usize>

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#### type Output = Wrapping<usize>

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### impl Add for Duration

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#### type Output = Duration

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### impl Add<&f32> for &f32

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#### type Output = <f32 as Add>::Output

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### impl Add<&f32> for f32

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#### type Output = <f32 as Add>::Output

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### impl Add<&f64> for &f64

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#### type Output = <f64 as Add>::Output

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### impl Add<&f64> for f64

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#### type Output = <f64 as Add>::Output

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### impl Add<&i8> for &i8

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#### type Output = <i8 as Add>::Output

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### impl Add<&i8> for i8

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#### type Output = <i8 as Add>::Output

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### impl Add<&i16> for &i16

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#### type Output = <i16 as Add>::Output

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### impl Add<&i16> for i16

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#### type Output = <i16 as Add>::Output

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### impl Add<&i32> for &i32

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#### type Output = <i32 as Add>::Output

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### impl Add<&i32> for i32

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#### type Output = <i32 as Add>::Output

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### impl Add<&i64> for &i64

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#### type Output = <i64 as Add>::Output

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### impl Add<&i64> for i64

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#### type Output = <i64 as Add>::Output

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### impl Add<&i128> for &i128

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#### type Output = <i128 as Add>::Output

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### impl Add<&i128> for i128

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#### type Output = <i128 as Add>::Output

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### impl Add<&isize> for &isize

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#### type Output = <isize as Add>::Output

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### impl Add<&isize> for isize

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#### type Output = <isize as Add>::Output

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### impl Add<&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.

Run

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.

Run

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;

Run
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#### type Output = String

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### impl Add<&u8> for &u8

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#### type Output = <u8 as Add>::Output

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### impl Add<&u8> for u8

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#### type Output = <u8 as Add>::Output

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### impl Add<&u16> for &u16

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#### type Output = <u16 as Add>::Output

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### impl Add<&u16> for u16

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#### type Output = <u16 as Add>::Output

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### impl Add<&u32> for &u32

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#### type Output = <u32 as Add>::Output

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### impl Add<&u32> for u32

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#### type Output = <u32 as Add>::Output

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### impl Add<&u64> for &u64

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#### type Output = <u64 as Add>::Output

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### impl Add<&u64> for u64

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#### type Output = <u64 as Add>::Output

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### impl Add<&u128> for &u128

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#### type Output = <u128 as Add>::Output

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### impl Add<&u128> for u128

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#### type Output = <u128 as Add>::Output

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### impl Add<&usize> for &usize

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#### type Output = <usize as Add>::Output

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### impl Add<&usize> for usize

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#### type Output = <usize as Add>::Output

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### impl Add<&Saturating<i8>> for &Saturating<i8>

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#### type Output = <Saturating<i8> as Add>::Output

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### impl Add<&Saturating<i8>> for Saturating<i8>

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#### type Output = <Saturating<i8> as Add>::Output

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### impl Add<&Saturating<i16>> for &Saturating<i16>

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#### type Output = <Saturating<i16> as Add>::Output

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### impl Add<&Saturating<i16>> for Saturating<i16>

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#### type Output = <Saturating<i16> as Add>::Output

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### impl Add<&Saturating<i32>> for &Saturating<i32>

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#### type Output = <Saturating<i32> as Add>::Output

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### impl Add<&Saturating<i32>> for Saturating<i32>

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#### type Output = <Saturating<i32> as Add>::Output

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### impl Add<&Saturating<i64>> for &Saturating<i64>

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#### type Output = <Saturating<i64> as Add>::Output

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### impl Add<&Saturating<i64>> for Saturating<i64>

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#### type Output = <Saturating<i64> as Add>::Output

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### impl Add<&Saturating<i128>> for &Saturating<i128>

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#### type Output = <Saturating<i128> as Add>::Output

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### impl Add<&Saturating<i128>> for Saturating<i128>

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#### type Output = <Saturating<i128> as Add>::Output

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### impl Add<&Saturating<isize>> for &Saturating<isize>

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#### type Output = <Saturating<isize> as Add>::Output

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### impl Add<&Saturating<isize>> for Saturating<isize>

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#### type Output = <Saturating<isize> as Add>::Output

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### impl Add<&Saturating<u8>> for &Saturating<u8>

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#### type Output = <Saturating<u8> as Add>::Output

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### impl Add<&Saturating<u8>> for Saturating<u8>

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#### type Output = <Saturating<u8> as Add>::Output

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### impl Add<&Saturating<u16>> for &Saturating<u16>

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#### type Output = <Saturating<u16> as Add>::Output

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### impl Add<&Saturating<u16>> for Saturating<u16>

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#### type Output = <Saturating<u16> as Add>::Output

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### impl Add<&Saturating<u32>> for &Saturating<u32>

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#### type Output = <Saturating<u32> as Add>::Output

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### impl Add<&Saturating<u32>> for Saturating<u32>

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#### type Output = <Saturating<u32> as Add>::Output

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### impl Add<&Saturating<u64>> for &Saturating<u64>

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#### type Output = <Saturating<u64> as Add>::Output

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### impl Add<&Saturating<u64>> for Saturating<u64>

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#### type Output = <Saturating<u64> as Add>::Output

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### impl Add<&Saturating<u128>> for &Saturating<u128>

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#### type Output = <Saturating<u128> as Add>::Output

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### impl Add<&Saturating<u128>> for Saturating<u128>

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#### type Output = <Saturating<u128> as Add>::Output

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### impl Add<&Saturating<usize>> for &Saturating<usize>

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#### type Output = <Saturating<usize> as Add>::Output

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### impl Add<&Saturating<usize>> for Saturating<usize>

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#### type Output = <Saturating<usize> as Add>::Output

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### impl Add<&Wrapping<i8>> for &Wrapping<i8>

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#### type Output = <Wrapping<i8> as Add>::Output

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### impl Add<&Wrapping<i8>> for Wrapping<i8>

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#### type Output = <Wrapping<i8> as Add>::Output

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### impl Add<&Wrapping<i16>> for &Wrapping<i16>

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#### type Output = <Wrapping<i16> as Add>::Output

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### impl Add<&Wrapping<i16>> for Wrapping<i16>

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#### type Output = <Wrapping<i16> as Add>::Output

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### impl Add<&Wrapping<i32>> for &Wrapping<i32>

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#### type Output = <Wrapping<i32> as Add>::Output

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### impl Add<&Wrapping<i32>> for Wrapping<i32>

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#### type Output = <Wrapping<i32> as Add>::Output

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### impl Add<&Wrapping<i64>> for &Wrapping<i64>

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#### type Output = <Wrapping<i64> as Add>::Output

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### impl Add<&Wrapping<i64>> for Wrapping<i64>

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#### type Output = <Wrapping<i64> as Add>::Output

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### impl Add<&Wrapping<i128>> for &Wrapping<i128>

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#### type Output = <Wrapping<i128> as Add>::Output

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### impl Add<&Wrapping<i128>> for Wrapping<i128>

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#### type Output = <Wrapping<i128> as Add>::Output

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### impl Add<&Wrapping<isize>> for &Wrapping<isize>

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#### type Output = <Wrapping<isize> as Add>::Output

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### impl Add<&Wrapping<isize>> for Wrapping<isize>

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#### type Output = <Wrapping<isize> as Add>::Output

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### impl Add<&Wrapping<u8>> for &Wrapping<u8>

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#### type Output = <Wrapping<u8> as Add>::Output

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### impl Add<&Wrapping<u8>> for Wrapping<u8>

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#### type Output = <Wrapping<u8> as Add>::Output

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### impl Add<&Wrapping<u16>> for &Wrapping<u16>

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#### type Output = <Wrapping<u16> as Add>::Output

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### impl Add<&Wrapping<u16>> for Wrapping<u16>

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#### type Output = <Wrapping<u16> as Add>::Output

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### impl Add<&Wrapping<u32>> for &Wrapping<u32>

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#### type Output = <Wrapping<u32> as Add>::Output

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### impl Add<&Wrapping<u32>> for Wrapping<u32>

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#### type Output = <Wrapping<u32> as Add>::Output

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### impl Add<&Wrapping<u64>> for &Wrapping<u64>

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#### type Output = <Wrapping<u64> as Add>::Output

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### impl Add<&Wrapping<u64>> for Wrapping<u64>

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#### type Output = <Wrapping<u64> as Add>::Output

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### impl Add<&Wrapping<u128>> for &Wrapping<u128>

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#### type Output = <Wrapping<u128> as Add>::Output

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### impl Add<&Wrapping<u128>> for Wrapping<u128>

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#### type Output = <Wrapping<u128> as Add>::Output

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### impl Add<&Wrapping<usize>> for &Wrapping<usize>

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#### type Output = <Wrapping<usize> as Add>::Output

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### impl Add<&Wrapping<usize>> for Wrapping<usize>

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#### type Output = <Wrapping<usize> as Add>::Output

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### impl Add<Duration> for Instant

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#### type Output = Instant

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### impl Add<Duration> for SystemTime

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#### type Output = SystemTime

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### impl<'a> Add for Cow<'a, str>

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#### type Output = Cow<'a, str>

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### impl<'a> Add<&'a str> for Cow<'a, str>

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#### type Output = Cow<'a, str>

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### impl<'a> Add<f32> for &'a f32

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#### type Output = <f32 as Add>::Output

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### impl<'a> Add<f64> for &'a f64

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#### type Output = <f64 as Add>::Output

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### impl<'a> Add<i8> for &'a i8

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#### type Output = <i8 as Add>::Output

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### impl<'a> Add<i16> for &'a i16

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#### type Output = <i16 as Add>::Output

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### impl<'a> Add<i32> for &'a i32

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#### type Output = <i32 as Add>::Output

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### impl<'a> Add<i64> for &'a i64

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#### type Output = <i64 as Add>::Output

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### impl<'a> Add<i128> for &'a i128

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#### type Output = <i128 as Add>::Output

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### impl<'a> Add<isize> for &'a isize

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#### type Output = <isize as Add>::Output

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### impl<'a> Add<u8> for &'a u8

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#### type Output = <u8 as Add>::Output

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### impl<'a> Add<u16> for &'a u16

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#### type Output = <u16 as Add>::Output

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### impl<'a> Add<u32> for &'a u32

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#### type Output = <u32 as Add>::Output

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### impl<'a> Add<u64> for &'a u64

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#### type Output = <u64 as Add>::Output

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### impl<'a> Add<u128> for &'a u128

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#### type Output = <u128 as Add>::Output

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### impl<'a> Add<usize> for &'a usize

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#### type Output = <usize as Add>::Output

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### impl<'a> Add<Saturating<i8>> for &'a Saturating<i8>

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#### type Output = <Saturating<i8> as Add>::Output

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### impl<'a> Add<Saturating<i16>> for &'a Saturating<i16>

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#### type Output = <Saturating<i16> as Add>::Output

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### impl<'a> Add<Saturating<i32>> for &'a Saturating<i32>

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#### type Output = <Saturating<i32> as Add>::Output

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### impl<'a> Add<Saturating<i64>> for &'a Saturating<i64>

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#### type Output = <Saturating<i64> as Add>::Output

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### impl<'a> Add<Saturating<i128>> for &'a Saturating<i128>

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#### type Output = <Saturating<i128> as Add>::Output

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### impl<'a> Add<Saturating<isize>> for &'a Saturating<isize>

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#### type Output = <Saturating<isize> as Add>::Output

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### impl<'a> Add<Saturating<u8>> for &'a Saturating<u8>

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#### type Output = <Saturating<u8> as Add>::Output

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### impl<'a> Add<Saturating<u16>> for &'a Saturating<u16>

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#### type Output = <Saturating<u16> as Add>::Output

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### impl<'a> Add<Saturating<u32>> for &'a Saturating<u32>

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#### type Output = <Saturating<u32> as Add>::Output

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### impl<'a> Add<Saturating<u64>> for &'a Saturating<u64>

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#### type Output = <Saturating<u64> as Add>::Output

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### impl<'a> Add<Saturating<u128>> for &'a Saturating<u128>

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#### type Output = <Saturating<u128> as Add>::Output

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### impl<'a> Add<Saturating<usize>> for &'a Saturating<usize>

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#### type Output = <Saturating<usize> as Add>::Output

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### impl<'a> Add<Wrapping<i8>> for &'a Wrapping<i8>

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#### type Output = <Wrapping<i8> as Add>::Output

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### impl<'a> Add<Wrapping<i16>> for &'a Wrapping<i16>

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#### type Output = <Wrapping<i16> as Add>::Output

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### impl<'a> Add<Wrapping<i32>> for &'a Wrapping<i32>

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#### type Output = <Wrapping<i32> as Add>::Output

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### impl<'a> Add<Wrapping<i64>> for &'a Wrapping<i64>

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#### type Output = <Wrapping<i64> as Add>::Output

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### impl<'a> Add<Wrapping<i128>> for &'a Wrapping<i128>

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#### type Output = <Wrapping<i128> as Add>::Output

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### impl<'a> Add<Wrapping<isize>> for &'a Wrapping<isize>

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#### type Output = <Wrapping<isize> as Add>::Output

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### impl<'a> Add<Wrapping<u8>> for &'a Wrapping<u8>

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#### type Output = <Wrapping<u8> as Add>::Output

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### impl<'a> Add<Wrapping<u16>> for &'a Wrapping<u16>

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#### type Output = <Wrapping<u16> as Add>::Output

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### impl<'a> Add<Wrapping<u32>> for &'a Wrapping<u32>

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#### type Output = <Wrapping<u32> as Add>::Output

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### impl<'a> Add<Wrapping<u64>> for &'a Wrapping<u64>

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#### type Output = <Wrapping<u64> as Add>::Output

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### impl<'a> Add<Wrapping<u128>> for &'a Wrapping<u128>

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#### type Output = <Wrapping<u128> as Add>::Output

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### impl<'a> Add<Wrapping<usize>> for &'a Wrapping<usize>

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#### type Output = <Wrapping<usize> as Add>::Output

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### impl<'lhs, 'rhs, T, const LANES: usize> Add<&'rhs Simd<T, LANES>> for &'lhs Simd<T, LANES>where T: SimdElement, Simd<T, LANES>: Add<Output = Simd<T, LANES>>, LaneCount<LANES>: SupportedLaneCount,

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#### type Output = Simd<T, LANES>

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### impl<T, const LANES: usize> Add<&Simd<T, LANES>> for Simd<T, LANES>where T: SimdElement, Simd<T, LANES>: Add<Output = Simd<T, LANES>>, LaneCount<LANES>: SupportedLaneCount,

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#### type Output = Simd<T, LANES>

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### impl<T, const LANES: usize> Add<Simd<T, LANES>> for &Simd<T, LANES>where T: SimdElement, Simd<T, LANES>: Add<Output = Simd<T, LANES>>, LaneCount<LANES>: SupportedLaneCount,

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#### type Output = Simd<T, LANES>

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### impl<const N: usize> Add for Simd<f32, N>where f32: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<f32, N>

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### impl<const N: usize> Add for Simd<f64, N>where f64: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<f64, N>

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### impl<const N: usize> Add for Simd<i8, N>where i8: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<i8, N>

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### impl<const N: usize> Add for Simd<i16, N>where i16: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<i16, N>

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### impl<const N: usize> Add for Simd<i32, N>where i32: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<i32, N>

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### impl<const N: usize> Add for Simd<i64, N>where i64: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<i64, N>

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### impl<const N: usize> Add for Simd<isize, N>where isize: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<isize, N>

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### impl<const N: usize> Add for Simd<u8, N>where u8: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<u8, N>

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### impl<const N: usize> Add for Simd<u16, N>where u16: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<u16, N>

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### impl<const N: usize> Add for Simd<u32, N>where u32: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<u32, N>

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### impl<const N: usize> Add for Simd<u64, N>where u64: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<u64, N>

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### impl<const N: usize> Add for Simd<usize, N>where usize: SimdElement, LaneCount<N>: SupportedLaneCount,

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#### type Output = Simd<usize, N>