Trait CheckedNeg

pub trait CheckedNeg: Sized {
    // Required method
    fn checked_neg(&self) -> Option<Self>;
}

Performs negation that returns None if the result can’t be represented.

Required Methods

fn checked_neg(&self) -> Option<Self>

Negates a number, returning None for results that can’t be represented, like signed MIN values that can’t be positive, or non-zero unsigned values that can’t be negative.

Examples

use num_traits::CheckedNeg;
use std::i32::MIN;

assert_eq!(CheckedNeg::checked_neg(&1_i32), Some(-1));
assert_eq!(CheckedNeg::checked_neg(&-1_i32), Some(1));
assert_eq!(CheckedNeg::checked_neg(&MIN), None);

assert_eq!(CheckedNeg::checked_neg(&0_u32), Some(0));
assert_eq!(CheckedNeg::checked_neg(&1_u32), None);

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl CheckedNeg for i8

fn checked_neg(&self) -> Option<i8>

impl CheckedNeg for i16

fn checked_neg(&self) -> Option<i16>

impl CheckedNeg for i32

fn checked_neg(&self) -> Option<i32>

impl CheckedNeg for i64

fn checked_neg(&self) -> Option<i64>

impl CheckedNeg for i128

fn checked_neg(&self) -> Option<i128>

impl CheckedNeg for isize

fn checked_neg(&self) -> Option<isize>

impl CheckedNeg for u8

fn checked_neg(&self) -> Option<u8>

impl CheckedNeg for u16

fn checked_neg(&self) -> Option<u16>

impl CheckedNeg for u32

fn checked_neg(&self) -> Option<u32>

impl CheckedNeg for u64

fn checked_neg(&self) -> Option<u64>

impl CheckedNeg for u128

fn checked_neg(&self) -> Option<u128>

impl CheckedNeg for usize

fn checked_neg(&self) -> Option<usize>

Implementors