std::ops::Neg - Rust
Description: API documentation for the Rust `Neg` trait in crate `std`.
Keywords: rust, rustlang, rust-lang, Neg

# 1.0.0[−][src]Trait std::ops::Neg

    #[lang = "neg"]
    pub trait Neg {
        type Output;
        #[must_use]
    fn neg(self) -> Self::Output;
    }

The unary negation operator `-`.

# Examples

An implementation of `Neg` for `Sign`, which allows the use of `-` to negate its value.

    use std::ops::Neg;

    #[derive(Debug, PartialEq)]
    enum Sign {
        Negative,
        Zero,
        Positive,
    }

    impl Neg for Sign {
        type Output = Sign;

        fn neg(self) -> Sign {
            match self {
                Sign::Negative => Sign::Positive,
                Sign::Zero => Sign::Zero,
                Sign::Positive => Sign::Negative,
            }
        }
    }

    // A negative positive is a negative.
    assert_eq!(-Sign::Positive, Sign::Negative);
    // A double negative is a positive.
    assert_eq!(-Sign::Negative, Sign::Positive);
    // Zero is its own negation.
    assert_eq!(-Sign::Zero, Sign::Zero);Run

## Associated Types

### `type Output`

The resulting type after applying the `-` operator.

## Required Methods

### `
#[must_use]
fn neg(self) -> Self::Output`

Performs the unary `-` operation.

## Implementors

###

`impl Neg for f32`

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#### `type Output = f32`

####

`fn neg(self) -> f32`

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###

`impl Neg for f64`

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#### `type Output = f64`

####

`fn neg(self) -> f64`

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###

`impl Neg for i128`

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#### `type Output = i128`

####

`fn neg(self) -> i128`

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###

`impl Neg for i16`

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#### `type Output = i16`

####

`fn neg(self) -> i16`

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###

`impl Neg for i32`

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#### `type Output = i32`

####

`fn neg(self) -> i32`

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###

`impl Neg for i64`

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#### `type Output = i64`

####

`fn neg(self) -> i64`

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###

`impl Neg for i8`

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#### `type Output = i8`

####

`fn neg(self) -> i8`

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###

`impl Neg for isize`

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#### `type Output = isize`

####

`fn neg(self) -> isize`

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###

`impl Neg for Wrapping<i128>`

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#### `type Output = Wrapping<i128>`

####

`fn neg(self) -> Wrapping<i128>`

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###

`impl Neg for Wrapping<i16>`

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#### `type Output = Wrapping<i16>`

####

`fn neg(self) -> Wrapping<i16>`

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###

`impl Neg for Wrapping<i32>`

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#### `type Output = Wrapping<i32>`

####

`fn neg(self) -> Wrapping<i32>`

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###

`impl Neg for Wrapping<i64>`

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#### `type Output = Wrapping<i64>`

####

`fn neg(self) -> Wrapping<i64>`

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###

`impl Neg for Wrapping<i8>`

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#### `type Output = Wrapping<i8>`

####

`fn neg(self) -> Wrapping<i8>`

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###

`impl Neg for Wrapping<isize>`

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#### `type Output = Wrapping<isize>`

####

`fn neg(self) -> Wrapping<isize>`

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###

`impl Neg for Wrapping<u128>`

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#### `type Output = Wrapping<u128>`

####

`fn neg(self) -> Wrapping<u128>`

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###

`impl Neg for Wrapping<u16>`

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#### `type Output = Wrapping<u16>`

####

`fn neg(self) -> Wrapping<u16>`

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###

`impl Neg for Wrapping<u32>`

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#### `type Output = Wrapping<u32>`

####

`fn neg(self) -> Wrapping<u32>`

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###

`impl Neg for Wrapping<u64>`

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#### `type Output = Wrapping<u64>`

####

`fn neg(self) -> Wrapping<u64>`

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###

`impl Neg for Wrapping<u8>`

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#### `type Output = Wrapping<u8>`

####

`fn neg(self) -> Wrapping<u8>`

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###

`impl Neg for Wrapping<usize>`

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#### `type Output = Wrapping<usize>`

####

`fn neg(self) -> Wrapping<usize>`

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###

`impl<'a> Neg for &'a f32`

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#### `type Output = <f32 as Neg>::Output`

####

`fn neg(self) -> <f32 as Neg>::Output`

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###

`impl<'a> Neg for &'a f64`

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#### `type Output = <f64 as Neg>::Output`

####

`fn neg(self) -> <f64 as Neg>::Output`

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###

`impl<'a> Neg for &'a i128`

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#### `type Output = <i128 as Neg>::Output`

####

`fn neg(self) -> <i128 as Neg>::Output`

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###

`impl<'a> Neg for &'a i16`

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#### `type Output = <i16 as Neg>::Output`

####

`fn neg(self) -> <i16 as Neg>::Output`

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###

`impl<'a> Neg for &'a i32`

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#### `type Output = <i32 as Neg>::Output`

####

`fn neg(self) -> <i32 as Neg>::Output`

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###

`impl<'a> Neg for &'a i64`

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#### `type Output = <i64 as Neg>::Output`

####

`fn neg(self) -> <i64 as Neg>::Output`

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###

`impl<'a> Neg for &'a i8`

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#### `type Output = <i8 as Neg>::Output`

####

`fn neg(self) -> <i8 as Neg>::Output`

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###

`impl<'a> Neg for &'a isize`

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#### `type Output = <isize as Neg>::Output`

####

`fn neg(self) -> <isize as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<i128>`

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#### `type Output = <Wrapping<i128> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<i128> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<i16>`

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#### `type Output = <Wrapping<i16> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<i16> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<i32>`

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#### `type Output = <Wrapping<i32> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<i32> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<i64>`

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#### `type Output = <Wrapping<i64> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<i64> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<i8>`

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#### `type Output = <Wrapping<i8> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<i8> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<isize>`

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#### `type Output = <Wrapping<isize> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<isize> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<u128>`

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#### `type Output = <Wrapping<u128> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<u128> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<u16>`

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#### `type Output = <Wrapping<u16> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<u16> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<u32>`

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#### `type Output = <Wrapping<u32> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<u32> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<u64>`

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#### `type Output = <Wrapping<u64> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<u64> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<u8>`

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#### `type Output = <Wrapping<u8> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<u8> as Neg>::Output`

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###

`impl<'a> Neg for &'a Wrapping<usize>`

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#### `type Output = <Wrapping<usize> as Neg>::Output`

####

`fn neg(self) -> <Wrapping<usize> as Neg>::Output`

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