Trait std::ops::Neg

pub trait Neg {
    type Output;
    fn neg(self) -> Self::Output;
}

The Neg trait is used to specify the functionality of unary -.

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);

Associated Types

Required Methods

Implementors

• impl Neg for std::num::Wrapping<usize>
• impl Neg for std::num::Wrapping<u8>
• impl Neg for std::num::Wrapping<u16>
• impl Neg for std::num::Wrapping<u32>
• impl Neg for std::num::Wrapping<u64>
• impl Neg for std::num::Wrapping<isize>
• impl Neg for std::num::Wrapping<i8>
• impl Neg for std::num::Wrapping<i16>
• impl Neg for std::num::Wrapping<i32>
• impl Neg for std::num::Wrapping<i64>
• impl<'a> Neg for &'a Wrapping<usize>
• impl<'a> Neg for &'a Wrapping<u8>
• impl<'a> Neg for &'a Wrapping<u16>
• impl<'a> Neg for &'a Wrapping<u32>
• impl<'a> Neg for &'a Wrapping<u64>
• impl<'a> Neg for &'a Wrapping<isize>
• impl<'a> Neg for &'a Wrapping<i8>
• impl<'a> Neg for &'a Wrapping<i16>
• impl<'a> Neg for &'a Wrapping<i32>
• impl<'a> Neg for &'a Wrapping<i64>
• impl Neg for std::num::Wrapping<u128>
• impl Neg for std::num::Wrapping<i128>
• impl<'a> Neg for &'a Wrapping<u128>
• impl<'a> Neg for &'a Wrapping<i128>
• impl Neg for isize
• impl Neg for i8
• impl Neg for i16
• impl Neg for i32
• impl Neg for i64
• impl Neg for f32
• impl Neg for f64
• impl<'a> Neg for &'a isize
• impl<'a> Neg for &'a i8
• impl<'a> Neg for &'a i16
• impl<'a> Neg for &'a i32
• impl<'a> Neg for &'a i64
• impl<'a> Neg for &'a f32
• impl<'a> Neg for &'a f64
• impl Neg for i128
• impl<'a> Neg for &'a i128