Struct std::num::NonZeroUsize

#[repr(transparent)]
pub struct NonZeroUsize(_);

An integer that is known not to equal zero.

This enables some memory layout optimization. For example, Option<NonZeroUsize> is the same size as usize:

use std::mem::size_of;
assert_eq!(size_of::<Option<core::num::NonZeroUsize>>(), size_of::<usize>());

Methods

impl NonZeroUsize

pub const unsafe fn new_unchecked(n: usize) -> NonZeroUsize

Creates a non-zero without checking the value.

Safety

The value must not be zero.

pub fn new(n: usize) -> Option<NonZeroUsize>

Creates a non-zero if the given value is not zero.

pub const fn get(self) -> usize

Returns the value as a primitive type.

Trait Implementations

impl Binary for NonZeroUsize

fn fmt(&self, f: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

impl Clone for NonZeroUsize

fn clone(&self) -> NonZeroUsize

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for NonZeroUsize

impl Debug for NonZeroUsize

fn fmt(&self, f: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

impl Display for NonZeroUsize

fn fmt(&self, f: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

impl Eq for NonZeroUsize

impl From<NonZeroU16> for NonZeroUsize

Converts NonZeroU16 to NonZeroUsize losslessly.

fn from(small: NonZeroU16) -> NonZeroUsize

Performs the conversion.

impl From<NonZeroU8> for NonZeroUsize

Converts NonZeroU8 to NonZeroUsize losslessly.

fn from(small: NonZeroU8) -> NonZeroUsize

Performs the conversion.

impl From<NonZeroUsize> for usize

fn from(nonzero: NonZeroUsize) -> usize

Performs the conversion.

impl FromStr for NonZeroUsize

type Err = ParseIntError

The associated error which can be returned from parsing.

fn from_str(src: &str) -> Result<NonZeroUsize, <NonZeroUsize as FromStr>::Err>

Parses a string s to return a value of this type.

impl Hash for NonZeroUsize

fn hash<__H>(&self, state: &mut __H) where
    __H: Hasher, 

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl LowerHex for NonZeroUsize

fn fmt(&self, f: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

impl Octal for NonZeroUsize

fn fmt(&self, f: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

impl Ord for NonZeroUsize

fn cmp(&self, other: &NonZeroUsize) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

🔬 This is a nightly-only experimental API. (clamp #44095)

Restrict a value to a certain interval.

impl PartialEq<NonZeroUsize> for NonZeroUsize

fn eq(&self, other: &NonZeroUsize) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &NonZeroUsize) -> bool

This method tests for !=.

impl PartialOrd<NonZeroUsize> for NonZeroUsize

fn partial_cmp(&self, other: &NonZeroUsize) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &NonZeroUsize) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &NonZeroUsize) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &NonZeroUsize) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &NonZeroUsize) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralEq for NonZeroUsize

impl StructuralPartialEq for NonZeroUsize

impl UpperHex for NonZeroUsize

fn fmt(&self, f: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.