# Struct std::num::NonZeroUsize 1.28.0[−][src]

    #[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>());

Run

## Implementations

### `impl NonZeroUsize`[src]

#### `pub const unsafe fn new_unchecked(n: usize) -> NonZeroUsize` 1.28.0 (const: 1.34.0)[src]

Creates a non-zero without checking the value.

# Safety

The value must not be zero.

#### `pub const fn new(n: usize) -> Option<NonZeroUsize>`1.28.0 (const: 1.47.0)[src]

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

#### `pub const fn get(self) -> usize` 1.28.0 (const: 1.34.0)[src]

Returns the value as a primitive type.

### `impl NonZeroUsize`[src]

#### `pub fn leading_zeros(self) -> u32`[src]

🔬 This is a nightly-only experimental API. (`nonzero_leading_trailing_zeros` #79143)

Returns the number of leading zeros in the binary representation of `self`.

On many architectures, this function can perform better than `leading_zeros()` on the underlying integer type, as special handling of zero can be avoided.

# Examples

Basic usage:

    #![feature(nonzero_leading_trailing_zeros)]
    let n = std::num::NonZeroUsize::new(usize::MAX).unwrap();

    assert_eq!(n.leading_zeros(), 0);

Run

#### `pub fn trailing_zeros(self) -> u32`[src]

🔬 This is a nightly-only experimental API. (`nonzero_leading_trailing_zeros` #79143)

Returns the number of trailing zeros in the binary representation of `self`.

On many architectures, this function can perform better than `trailing_zeros()` on the underlying integer type, as special handling of zero can be avoided.

# Examples

Basic usage:

    #![feature(nonzero_leading_trailing_zeros)]
    let n = std::num::NonZeroUsize::new(0b0101000).unwrap();

    assert_eq!(n.trailing_zeros(), 3);

Run

### `impl NonZeroUsize`[src]

#### `pub fn is_power_of_two(self) -> bool`[src]

🔬 This is a nightly-only experimental API. (`nonzero_is_power_of_two` #81106)

Returns `true` if and only if `self == (1 << k)` for some `k`.

On many architectures, this function can perform better than `is_power_of_two()` on the underlying integer type, as special handling of zero can be avoided.

# Examples

Basic usage:

    #![feature(nonzero_is_power_of_two)]

    let eight = std::num::NonZeroUsize::new(8).unwrap();
    assert!(eight.is_power_of_two());
    let ten = std::num::NonZeroUsize::new(10).unwrap();
    assert!(!ten.is_power_of_two());

Run

## Trait Implementations

### `impl Binary for NonZeroUsize`[src]

#### `pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

Formats the value using the given formatter.

### `impl BitOr<NonZeroUsize> for usize` 1.45.0[src]

#### `type Output = NonZeroUsize`

The resulting type after applying the `|` operator.

#### `pub fn bitor(self, rhs: NonZeroUsize) -> <usize as BitOr<NonZeroUsize>>::Output`[src]

Performs the `|` operation. Read more

### `impl BitOr<NonZeroUsize> for NonZeroUsize` 1.45.0[src]

#### `type Output = NonZeroUsize`

The resulting type after applying the `|` operator.

#### `pub fn bitor(
self,
rhs: NonZeroUsize
) -> <NonZeroUsize as BitOr<NonZeroUsize>>::Output`[src]

Performs the `|` operation. Read more

### `impl BitOr<usize> for NonZeroUsize` 1.45.0[src]

#### `type Output = NonZeroUsize`

The resulting type after applying the `|` operator.

#### `pub fn bitor(self, rhs: usize) -> <NonZeroUsize as BitOr<usize>>::Output`[src]

Performs the `|` operation. Read more

### `impl BitOrAssign<NonZeroUsize> for NonZeroUsize` 1.45.0[src]

#### `pub fn bitor_assign(&mut self, rhs: NonZeroUsize)`[src]

Performs the `|=` operation. Read more

### `impl BitOrAssign<usize> for NonZeroUsize` 1.45.0[src]

#### `pub fn bitor_assign(&mut self, rhs: usize)`[src]

Performs the `|=` operation. Read more

### `impl Clone for NonZeroUsize`[src]

#### `pub fn clone(&self) -> NonZeroUsize`[src]

Returns a copy of the value. Read more

#### `pub fn clone_from(&mut self, source: &Self)`1.0.0[src]

Performs copy-assignment from `source`. Read more

### `impl Copy for NonZeroUsize`[src]

### `impl Debug for NonZeroUsize`[src]

#### `pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

Formats the value using the given formatter. Read more

### `impl Display for NonZeroUsize`[src]

#### `pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

Formats the value using the given formatter. Read more

### `impl Div<NonZeroUsize> for usize` 1.51.0[src]

#### `type Output = usize`

The resulting type after applying the `/` operator.

#### `pub fn div(self, other: NonZeroUsize) -> usize`[src]

This operation rounds towards zero, truncating any fractional part of the exact result, and cannot panic.

### `impl Eq for NonZeroUsize`[src]

### `impl From<NonZeroU16> for NonZeroUsize` 1.41.0[src]

Converts `NonZeroU16` to `NonZeroUsize` losslessly.

#### `pub fn from(small: NonZeroU16) -> NonZeroUsize`[src]

Performs the conversion.

### `impl From<NonZeroU8> for NonZeroUsize` 1.41.0[src]

Converts `NonZeroU8` to `NonZeroUsize` losslessly.

#### `pub fn from(small: NonZeroU8) -> NonZeroUsize`[src]

Performs the conversion.

### `impl From<NonZeroUsize> for usize` 1.31.0[src]

#### `pub fn from(nonzero: NonZeroUsize) -> usize`[src]

Converts a `NonZeroUsize` into an `usize`

### `impl FromStr for NonZeroUsize` 1.35.0[src]

#### `type Err = ParseIntError`

The associated error which can be returned from parsing.

#### `pub fn from_str(
src: &str
) -> Result<NonZeroUsize, <NonZeroUsize as FromStr>::Err>`[src]

Parses a string `s` to return a value of this type. Read more

### `impl Hash for NonZeroUsize`[src]

#### `pub fn hash<__H>(&self, state: &mut __H) where
__H: Hasher,` [src]

Feeds this value into the given `Hasher`. Read more

#### `pub fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,` 1.3.0[src]

Feeds a slice of this type into the given `Hasher`. Read more

### `impl LowerHex for NonZeroUsize`[src]

#### `pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

Formats the value using the given formatter.

### `impl Octal for NonZeroUsize`[src]

#### `pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

Formats the value using the given formatter.

### `impl Ord for NonZeroUsize`[src]

#### `pub fn cmp(&self, other: &NonZeroUsize) -> Ordering`[src]

This method returns an `Ordering` between `self` and `other`. Read more

#### `#[must_use]pub fn max(self, other: Self) -> Self` 1.21.0[src]

Compares and returns the maximum of two values. Read more

#### `#[must_use]pub fn min(self, other: Self) -> Self` 1.21.0[src]

Compares and returns the minimum of two values. Read more

#### `#[must_use]pub fn clamp(self, min: Self, max: Self) -> Self` 1.50.0[src]

Restrict a value to a certain interval. Read more

### `impl PartialEq<NonZeroUsize> for NonZeroUsize`[src]

#### `pub fn eq(&self, other: &NonZeroUsize) -> bool`[src]

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

#### `pub fn ne(&self, other: &NonZeroUsize) -> bool`[src]

This method tests for `!=`.

### `impl PartialOrd<NonZeroUsize> for NonZeroUsize`[src]

#### `pub fn partial_cmp(&self, other: &NonZeroUsize) -> Option<Ordering>`[src]

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

#### `pub fn lt(&self, other: &NonZeroUsize) -> bool`[src]

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

#### `pub fn le(&self, other: &NonZeroUsize) -> bool`[src]

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

#### `pub fn gt(&self, other: &NonZeroUsize) -> bool`[src]

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

#### `pub fn ge(&self, other: &NonZeroUsize) -> bool`[src]

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

### `impl Rem<NonZeroUsize> for usize` 1.51.0[src]

#### `type Output = usize`

The resulting type after applying the `%` operator.

#### `pub fn rem(self, other: NonZeroUsize) -> usize`[src]

This operation satisfies `n % d == n - (n / d) * d`, and cannot panic.

### `impl StructuralEq for NonZeroUsize`[src]

### `impl StructuralPartialEq for NonZeroUsize`[src]

### `impl TryFrom<NonZeroI128> for NonZeroUsize` 1.49.0[src]

Attempts to convert `NonZeroI128` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroI128
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroI128>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroI16> for NonZeroUsize` 1.49.0[src]

Attempts to convert `NonZeroI16` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroI16
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroI16>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroI32> for NonZeroUsize` 1.49.0[src]

Attempts to convert `NonZeroI32` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroI32
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroI32>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroI64> for NonZeroUsize` 1.49.0[src]

Attempts to convert `NonZeroI64` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroI64
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroI64>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroI8> for NonZeroUsize` 1.49.0[src]

Attempts to convert `NonZeroI8` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroI8
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroI8>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroIsize> for NonZeroUsize` 1.49.0[src]

Attempts to convert `NonZeroIsize` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroIsize
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroIsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroU128> for NonZeroUsize` 1.49.0[src]

Attempts to convert `NonZeroU128` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroU128
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroU128>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroU32> for NonZeroUsize` 1.49.0[src]

Attempts to convert `NonZeroU32` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroU32
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroU32>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroU64> for NonZeroUsize` 1.49.0[src]

Attempts to convert `NonZeroU64` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroU64
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroU64>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroU32` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroU32`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroI128` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroI128`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroI128, <NonZeroI128 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroIsize` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroIsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroIsize, <NonZeroIsize as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroI16` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroI16`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroI16, <NonZeroI16 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroI8` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroI8`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroU64` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroU64`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroU64, <NonZeroU64 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroI64` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroI64`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroI64, <NonZeroI64 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroU128` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroU128`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroU128, <NonZeroU128 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroU16` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroU16`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroU16, <NonZeroU16 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroU8` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroU8`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroU8, <NonZeroU8 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<NonZeroUsize> for NonZeroI32` 1.49.0[src]

Attempts to convert `NonZeroUsize` to `NonZeroI32`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: NonZeroUsize
) -> Result<NonZeroI32, <NonZeroI32 as TryFrom<NonZeroUsize>>::Error>`[src]

Performs the conversion.

### `impl TryFrom<usize> for NonZeroUsize` 1.46.0[src]

Attempts to convert `usize` to `NonZeroUsize`.

#### `type Error = TryFromIntError`

The type returned in the event of a conversion error.

#### `pub fn try_from(
value: usize
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<usize>>::Error>`[src]

Performs the conversion.

### `impl UpperHex for NonZeroUsize`[src]

#### `pub fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>`[src]

Formats the value using the given formatter.

## Auto Trait Implementations

### `impl RefUnwindSafe for NonZeroUsize`[src]

### `impl Send for NonZeroUsize`[src]

### `impl Sync for NonZeroUsize`[src]

### `impl Unpin for NonZeroUsize`[src]

### `impl UnwindSafe for NonZeroUsize`[src]

## Blanket Implementations

### `impl<T> Any for T where
T: 'static + ?Sized,` [src]

#### `pub fn type_id(&self) -> TypeId`[src]

Gets the `TypeId` of `self`. Read more

### `impl<T> Borrow<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow(&self) -> &Tⓘ

### Notable traits for &'_ mut F

`impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized, type Output = <F as Future>::Output;impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[src]

Immutably borrows from an owned value. Read more

### `impl<T> BorrowMut<T> for T where
T: ?Sized,` [src]

#### `pub fn borrow_mut(&mut self) -> &mut Tⓘ

### Notable traits for &'_ mut F

`impl<'_, F> Future for &'_ mut F where
F: Unpin + Future + ?Sized, type Output = <F as Future>::Output;impl<'_, I> Iterator for &'_ mut I where
I: Iterator + ?Sized, type Item = <I as Iterator>::Item;impl<R: Read + ?Sized> Read for &mut Rimpl<W: Write + ?Sized> Write for &mut W`
`[src]

Mutably borrows from an owned value. Read more

### `impl<T> From<T> for T`[src]

#### `pub fn from(t: T) -> T`[src]

Performs the conversion.

### `impl<T, U> Into<U> for T where
U: From<T>,` [src]

#### `pub fn into(self) -> U`[src]

Performs the conversion.

### `impl<T> ToOwned for T where
T: Clone,` [src]

#### `type Owned = T`

The resulting type after obtaining ownership.

#### `pub fn to_owned(&self) -> T`[src]

Creates owned data from borrowed data, usually by cloning. Read more

#### `pub fn clone_into(&self, target: &mut T)`[src]

🔬 This is a nightly-only experimental API. (`toowned_clone_into` #41263)

recently added

Uses borrowed data to replace owned data, usually by cloning. Read more

### `impl<T> ToString for T where
T: Display + ?Sized,` [src]

#### `pub default fn to_string(&self) -> String`[src]

Converts the given value to a `String`. Read more

### `impl<T, U> TryFrom<U> for T where
U: Into<T>,` [src]

#### `type Error = Infallible`

The type returned in the event of a conversion error.

#### `pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

Performs the conversion.

### `impl<T, U> TryInto<U> for T where
U: TryFrom<T>,` [src]

#### `type Error = <U as TryFrom<T>>::Error`

The type returned in the event of a conversion error.

#### `pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`[src]

Performs the conversion.