`#[repr(transparent)]pub struct NonZeroI8(i8);`

## Expand description

An integer that is known not to equal zero.

This enables some memory layout optimization.
For example, `Option<NonZeroI8>`

is the same size as `i8`

:

```
use std::mem::size_of;
assert_eq!(size_of::<Option<core::num::NonZeroI8>>(), size_of::<i8>());
```

## Layout

`NonZeroI8`

is guaranteed to have the same layout and bit validity as `i8`

with the exception that `0`

is not a valid instance.
`Option<NonZeroI8>`

is guaranteed to be compatible with `i8`

,
including in FFI.

Thanks to the null pointer optimization,
`NonZeroI8`

and `Option<NonZeroI8>`

are guaranteed to have the same size and alignment:

```
use std::num::NonZeroI8;
assert_eq!(size_of::<NonZeroI8>(), size_of::<Option<NonZeroI8>>());
assert_eq!(align_of::<NonZeroI8>(), align_of::<Option<NonZeroI8>>());
```

## Tuple Fields§

§`0: i8`

## Implementations§

source§### impl NonZeroI8

### impl NonZeroI8

const: 1.34.0 · source#### pub const unsafe fn new_unchecked(n: i8) -> NonZeroI8

#### pub const unsafe fn new_unchecked(n: i8) -> NonZeroI8

Creates a non-zero without checking whether the value is non-zero. This results in undefined behaviour if the value is zero.

##### Safety

The value must not be zero.

source§### impl NonZeroI8

### impl NonZeroI8

1.53.0 (const: 1.53.0) · source#### pub const fn leading_zeros(self) -> u32

#### pub const fn leading_zeros(self) -> u32

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:

```
let n = std::num::NonZeroI8::new(-1i8).unwrap();
assert_eq!(n.leading_zeros(), 0);
```

1.53.0 (const: 1.53.0) · source#### pub const fn trailing_zeros(self) -> u32

#### pub const fn trailing_zeros(self) -> u32

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:

```
let n = std::num::NonZeroI8::new(0b0101000).unwrap();
assert_eq!(n.trailing_zeros(), 3);
```

source§### impl NonZeroI8

### impl NonZeroI8

1.64.0 (const: 1.64.0) · source#### pub const fn checked_abs(self) -> Option<NonZeroI8>

#### pub const fn checked_abs(self) -> Option<NonZeroI8>

1.64.0 (const: 1.64.0) · source#### pub const fn overflowing_abs(self) -> (NonZeroI8, bool)

#### pub const fn overflowing_abs(self) -> (NonZeroI8, bool)

Computes the absolute value of self,
with overflow information, see
`i8::overflowing_abs`

.

##### Example

```
let pos = NonZeroI8::new(1)?;
let neg = NonZeroI8::new(-1)?;
let min = NonZeroI8::new(i8::MIN)?;
assert_eq!((pos, false), pos.overflowing_abs());
assert_eq!((pos, false), neg.overflowing_abs());
assert_eq!((min, true), min.overflowing_abs());
```

1.64.0 (const: 1.64.0) · source#### pub const fn saturating_abs(self) -> NonZeroI8

#### pub const fn saturating_abs(self) -> NonZeroI8

Saturating absolute value, see
`i8::saturating_abs`

.

##### Example

```
let pos = NonZeroI8::new(1)?;
let neg = NonZeroI8::new(-1)?;
let min = NonZeroI8::new(i8::MIN)?;
let min_plus = NonZeroI8::new(i8::MIN + 1)?;
let max = NonZeroI8::new(i8::MAX)?;
assert_eq!(pos, pos.saturating_abs());
assert_eq!(pos, neg.saturating_abs());
assert_eq!(max, min.saturating_abs());
assert_eq!(max, min_plus.saturating_abs());
```

1.64.0 (const: 1.64.0) · source#### pub const fn wrapping_abs(self) -> NonZeroI8

#### pub const fn wrapping_abs(self) -> NonZeroI8

Wrapping absolute value, see
`i8::wrapping_abs`

.

##### Example

```
let pos = NonZeroI8::new(1)?;
let neg = NonZeroI8::new(-1)?;
let min = NonZeroI8::new(i8::MIN)?;
assert_eq!(pos, pos.wrapping_abs());
assert_eq!(pos, neg.wrapping_abs());
assert_eq!(min, min.wrapping_abs());
assert_eq!(max, (-max).wrapping_abs());
```

1.64.0 (const: 1.64.0) · source#### pub const fn unsigned_abs(self) -> NonZeroU8

#### pub const fn unsigned_abs(self) -> NonZeroU8

Computes the absolute value of self without any wrapping or panicking.

##### Example

```
let u_pos = NonZeroU8::new(1)?;
let i_pos = NonZeroI8::new(1)?;
let i_neg = NonZeroI8::new(-1)?;
let i_min = NonZeroI8::new(i8::MIN)?;
let u_max = NonZeroU8::new(u8::MAX / 2 + 1)?;
assert_eq!(u_pos, i_pos.unsigned_abs());
assert_eq!(u_pos, i_neg.unsigned_abs());
assert_eq!(u_max, i_min.unsigned_abs());
```

1.71.0 (const: 1.71.0) · source#### pub const fn is_positive(self) -> bool

#### pub const fn is_positive(self) -> bool

Returns `true`

if `self`

is positive and `false`

if the
number is negative.

##### Example

```
let pos_five = NonZeroI8::new(5)?;
let neg_five = NonZeroI8::new(-5)?;
assert!(pos_five.is_positive());
assert!(!neg_five.is_positive());
```

1.71.0 (const: 1.71.0) · source#### pub const fn is_negative(self) -> bool

#### pub const fn is_negative(self) -> bool

Returns `true`

if `self`

is negative and `false`

if the
number is positive.

##### Example

```
let pos_five = NonZeroI8::new(5)?;
let neg_five = NonZeroI8::new(-5)?;
assert!(neg_five.is_negative());
assert!(!pos_five.is_negative());
```

1.71.0 (const: 1.71.0) · source#### pub const fn checked_neg(self) -> Option<NonZeroI8>

#### pub const fn checked_neg(self) -> Option<NonZeroI8>

Checked negation. Computes `-self`

,
returning `None`

if `self == NonZeroI8::MIN`

.

##### Example

```
let pos_five = NonZeroI8::new(5)?;
let neg_five = NonZeroI8::new(-5)?;
let min = NonZeroI8::new(i8::MIN)?;
assert_eq!(pos_five.checked_neg(), Some(neg_five));
assert_eq!(min.checked_neg(), None);
```

1.71.0 (const: 1.71.0) · source#### pub const fn overflowing_neg(self) -> (NonZeroI8, bool)

#### pub const fn overflowing_neg(self) -> (NonZeroI8, bool)

Negates self, overflowing if this is equal to the minimum value.

See `i8::overflowing_neg`

for documentation on overflow behaviour.

##### Example

```
let pos_five = NonZeroI8::new(5)?;
let neg_five = NonZeroI8::new(-5)?;
let min = NonZeroI8::new(i8::MIN)?;
assert_eq!(pos_five.overflowing_neg(), (neg_five, false));
assert_eq!(min.overflowing_neg(), (min, true));
```

1.71.0 (const: 1.71.0) · source#### pub const fn saturating_neg(self) -> NonZeroI8

#### pub const fn saturating_neg(self) -> NonZeroI8

Saturating negation. Computes `-self`

,
returning `NonZeroI8::MAX`

if `self == NonZeroI8::MIN`

instead of overflowing.

##### Example

```
let pos_five = NonZeroI8::new(5)?;
let neg_five = NonZeroI8::new(-5)?;
let min = NonZeroI8::new(i8::MIN)?;
let min_plus_one = NonZeroI8::new(i8::MIN + 1)?;
let max = NonZeroI8::new(i8::MAX)?;
assert_eq!(pos_five.saturating_neg(), neg_five);
assert_eq!(min.saturating_neg(), max);
assert_eq!(max.saturating_neg(), min_plus_one);
```

1.71.0 (const: 1.71.0) · source#### pub const fn wrapping_neg(self) -> NonZeroI8

#### pub const fn wrapping_neg(self) -> NonZeroI8

Wrapping (modular) negation. Computes `-self`

, wrapping around at the boundary
of the type.

See `i8::wrapping_neg`

for documentation on overflow behaviour.

##### Example

```
let pos_five = NonZeroI8::new(5)?;
let neg_five = NonZeroI8::new(-5)?;
let min = NonZeroI8::new(i8::MIN)?;
assert_eq!(pos_five.wrapping_neg(), neg_five);
assert_eq!(min.wrapping_neg(), min);
```

source§### impl NonZeroI8

### impl NonZeroI8

1.64.0 (const: 1.64.0) · source#### pub const fn checked_mul(self, other: NonZeroI8) -> Option<NonZeroI8>

#### pub const fn checked_mul(self, other: NonZeroI8) -> Option<NonZeroI8>

Multiplies two non-zero integers together.
Checks for overflow and returns `None`

on overflow.
As a consequence, the result cannot wrap to zero.

##### Examples

```
let two = NonZeroI8::new(2)?;
let four = NonZeroI8::new(4)?;
let max = NonZeroI8::new(i8::MAX)?;
assert_eq!(Some(four), two.checked_mul(two));
assert_eq!(None, max.checked_mul(two));
```

1.64.0 (const: 1.64.0) · source#### pub const fn saturating_mul(self, other: NonZeroI8) -> NonZeroI8

#### pub const fn saturating_mul(self, other: NonZeroI8) -> NonZeroI8

Multiplies two non-zero integers together.
Return `NonZeroI8::MAX`

on overflow.

##### Examples

```
let two = NonZeroI8::new(2)?;
let four = NonZeroI8::new(4)?;
let max = NonZeroI8::new(i8::MAX)?;
assert_eq!(four, two.saturating_mul(two));
assert_eq!(max, four.saturating_mul(max));
```

source#### pub const unsafe fn unchecked_mul(self, other: NonZeroI8) -> NonZeroI8

🔬This is a nightly-only experimental API. (`nonzero_ops`

#84186)

#### pub const unsafe fn unchecked_mul(self, other: NonZeroI8) -> NonZeroI8

`nonzero_ops`

#84186)Multiplies two non-zero integers together,
assuming overflow cannot occur.
Overflow is unchecked, and it is undefined behaviour to overflow
*even if the result would wrap to a non-zero value*.
The behaviour is undefined as soon as
`self * rhs > i8::MAX`

, or `self * rhs < i8::MIN`

.

##### Examples

```
#![feature(nonzero_ops)]
let two = NonZeroI8::new(2)?;
let four = NonZeroI8::new(4)?;
assert_eq!(four, unsafe { two.unchecked_mul(two) });
```

1.64.0 (const: 1.64.0) · source#### pub const fn checked_pow(self, other: u32) -> Option<NonZeroI8>

#### pub const fn checked_pow(self, other: u32) -> Option<NonZeroI8>

Raises non-zero value to an integer power.
Checks for overflow and returns `None`

on overflow.
As a consequence, the result cannot wrap to zero.

##### Examples

```
let three = NonZeroI8::new(3)?;
let twenty_seven = NonZeroI8::new(27)?;
let half_max = NonZeroI8::new(i8::MAX / 2)?;
assert_eq!(Some(twenty_seven), three.checked_pow(3));
assert_eq!(None, half_max.checked_pow(3));
```

1.64.0 (const: 1.64.0) · source#### pub const fn saturating_pow(self, other: u32) -> NonZeroI8

#### pub const fn saturating_pow(self, other: u32) -> NonZeroI8

Raise non-zero value to an integer power.
Return `NonZeroI8::MIN`

or `NonZeroI8::MAX`

on overflow.

##### Examples

```
let three = NonZeroI8::new(3)?;
let twenty_seven = NonZeroI8::new(27)?;
let max = NonZeroI8::new(i8::MAX)?;
assert_eq!(twenty_seven, three.saturating_pow(3));
assert_eq!(max, max.saturating_pow(3));
```

## Trait Implementations§

1.45.0 · source§### impl BitOrAssign<NonZeroI8> for NonZeroI8

### impl BitOrAssign<NonZeroI8> for NonZeroI8

source§#### fn bitor_assign(&mut self, rhs: NonZeroI8)

#### fn bitor_assign(&mut self, rhs: NonZeroI8)

`|=`

operation. Read more1.45.0 · source§### impl BitOrAssign<i8> for NonZeroI8

### impl BitOrAssign<i8> for NonZeroI8

source§#### fn bitor_assign(&mut self, rhs: i8)

#### fn bitor_assign(&mut self, rhs: i8)

`|=`

operation. Read more1.41.0 · source§### impl From<NonZeroI8> for NonZeroI128

### impl From<NonZeroI8> for NonZeroI128

source§#### fn from(small: NonZeroI8) -> NonZeroI128

#### fn from(small: NonZeroI8) -> NonZeroI128

Converts `NonZeroI8`

to `NonZeroI128`

losslessly.

1.41.0 · source§### impl From<NonZeroI8> for NonZeroI16

### impl From<NonZeroI8> for NonZeroI16

source§#### fn from(small: NonZeroI8) -> NonZeroI16

#### fn from(small: NonZeroI8) -> NonZeroI16

Converts `NonZeroI8`

to `NonZeroI16`

losslessly.

1.41.0 · source§### impl From<NonZeroI8> for NonZeroI32

### impl From<NonZeroI8> for NonZeroI32

source§#### fn from(small: NonZeroI8) -> NonZeroI32

#### fn from(small: NonZeroI8) -> NonZeroI32

Converts `NonZeroI8`

to `NonZeroI32`

losslessly.

1.41.0 · source§### impl From<NonZeroI8> for NonZeroI64

### impl From<NonZeroI8> for NonZeroI64

source§#### fn from(small: NonZeroI8) -> NonZeroI64

#### fn from(small: NonZeroI8) -> NonZeroI64

Converts `NonZeroI8`

to `NonZeroI64`

losslessly.

1.41.0 · source§### impl From<NonZeroI8> for NonZeroIsize

### impl From<NonZeroI8> for NonZeroIsize

source§#### fn from(small: NonZeroI8) -> NonZeroIsize

#### fn from(small: NonZeroI8) -> NonZeroIsize

Converts `NonZeroI8`

to `NonZeroIsize`

losslessly.

source§### impl Ord for NonZeroI8

### impl Ord for NonZeroI8

source§### impl PartialEq<NonZeroI8> for NonZeroI8

### impl PartialEq<NonZeroI8> for NonZeroI8

source§### impl PartialOrd<NonZeroI8> for NonZeroI8

### impl PartialOrd<NonZeroI8> for NonZeroI8

1.0.0 · source§#### fn le(&self, other: &Rhs) -> bool

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

`self`

and `other`

) and is used by the `<=`

operator. Read more1.49.0 · source§### impl TryFrom<NonZeroI128> for NonZeroI8

### impl TryFrom<NonZeroI128> for NonZeroI8

source§#### fn try_from(
value: NonZeroI128
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI128>>::Error>

#### fn try_from( value: NonZeroI128 ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI128>>::Error>

Attempts to convert `NonZeroI128`

to `NonZeroI8`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroI16> for NonZeroI8

### impl TryFrom<NonZeroI16> for NonZeroI8

source§#### fn try_from(
value: NonZeroI16
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI16>>::Error>

#### fn try_from( value: NonZeroI16 ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI16>>::Error>

Attempts to convert `NonZeroI16`

to `NonZeroI8`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroI32> for NonZeroI8

### impl TryFrom<NonZeroI32> for NonZeroI8

source§#### fn try_from(
value: NonZeroI32
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI32>>::Error>

#### fn try_from( value: NonZeroI32 ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI32>>::Error>

Attempts to convert `NonZeroI32`

to `NonZeroI8`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroI64> for NonZeroI8

### impl TryFrom<NonZeroI64> for NonZeroI8

source§#### fn try_from(
value: NonZeroI64
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI64>>::Error>

#### fn try_from( value: NonZeroI64 ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI64>>::Error>

Attempts to convert `NonZeroI64`

to `NonZeroI8`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroI8> for NonZeroU128

### impl TryFrom<NonZeroI8> for NonZeroU128

source§#### fn try_from(
value: NonZeroI8
) -> Result<NonZeroU128, <NonZeroU128 as TryFrom<NonZeroI8>>::Error>

#### fn try_from( value: NonZeroI8 ) -> Result<NonZeroU128, <NonZeroU128 as TryFrom<NonZeroI8>>::Error>

Attempts to convert `NonZeroI8`

to `NonZeroU128`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroI8> for NonZeroU16

### impl TryFrom<NonZeroI8> for NonZeroU16

source§#### fn try_from(
value: NonZeroI8
) -> Result<NonZeroU16, <NonZeroU16 as TryFrom<NonZeroI8>>::Error>

#### fn try_from( value: NonZeroI8 ) -> Result<NonZeroU16, <NonZeroU16 as TryFrom<NonZeroI8>>::Error>

Attempts to convert `NonZeroI8`

to `NonZeroU16`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroI8> for NonZeroU32

### impl TryFrom<NonZeroI8> for NonZeroU32

source§#### fn try_from(
value: NonZeroI8
) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroI8>>::Error>

#### fn try_from( value: NonZeroI8 ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroI8>>::Error>

Attempts to convert `NonZeroI8`

to `NonZeroU32`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroI8> for NonZeroU64

### impl TryFrom<NonZeroI8> for NonZeroU64

source§#### fn try_from(
value: NonZeroI8
) -> Result<NonZeroU64, <NonZeroU64 as TryFrom<NonZeroI8>>::Error>

#### fn try_from( value: NonZeroI8 ) -> Result<NonZeroU64, <NonZeroU64 as TryFrom<NonZeroI8>>::Error>

Attempts to convert `NonZeroI8`

to `NonZeroU64`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroI8> for NonZeroUsize

### impl TryFrom<NonZeroI8> for NonZeroUsize

source§#### fn try_from(
value: NonZeroI8
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroI8>>::Error>

#### fn try_from( value: NonZeroI8 ) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroI8>>::Error>

Attempts to convert `NonZeroI8`

to `NonZeroUsize`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroIsize> for NonZeroI8

### impl TryFrom<NonZeroIsize> for NonZeroI8

source§#### fn try_from(
value: NonZeroIsize
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroIsize>>::Error>

#### fn try_from( value: NonZeroIsize ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroIsize>>::Error>

Attempts to convert `NonZeroIsize`

to `NonZeroI8`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroU128> for NonZeroI8

### impl TryFrom<NonZeroU128> for NonZeroI8

source§#### fn try_from(
value: NonZeroU128
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU128>>::Error>

#### fn try_from( value: NonZeroU128 ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU128>>::Error>

Attempts to convert `NonZeroU128`

to `NonZeroI8`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroU16> for NonZeroI8

### impl TryFrom<NonZeroU16> for NonZeroI8

source§#### fn try_from(
value: NonZeroU16
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU16>>::Error>

#### fn try_from( value: NonZeroU16 ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU16>>::Error>

Attempts to convert `NonZeroU16`

to `NonZeroI8`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroU32> for NonZeroI8

### impl TryFrom<NonZeroU32> for NonZeroI8

source§#### fn try_from(
value: NonZeroU32
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU32>>::Error>

#### fn try_from( value: NonZeroU32 ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU32>>::Error>

Attempts to convert `NonZeroU32`

to `NonZeroI8`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroU64> for NonZeroI8

### impl TryFrom<NonZeroU64> for NonZeroI8

source§#### fn try_from(
value: NonZeroU64
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU64>>::Error>

#### fn try_from( value: NonZeroU64 ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU64>>::Error>

Attempts to convert `NonZeroU64`

to `NonZeroI8`

.

§#### type Error = TryFromIntError

#### type Error = TryFromIntError

1.49.0 · source§### impl TryFrom<NonZeroUsize> for NonZeroI8

### impl TryFrom<NonZeroUsize> for NonZeroI8

source§#### fn try_from(
value: NonZeroUsize
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroUsize>>::Error>

#### fn try_from( value: NonZeroUsize ) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroUsize>>::Error>

Attempts to convert `NonZeroUsize`

to `NonZeroI8`

.