pub struct NonZeroI8(/* private fields */);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>());RunLayout
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>>());RunImplementations§
source§impl NonZeroI8
impl NonZeroI8
const: 1.34.0 · sourcepub const unsafe fn new_unchecked(n: i8) -> Self
pub const unsafe fn new_unchecked(n: i8) -> Self
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) · sourcepub 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);Run1.53.0 (const: 1.53.0) · sourcepub 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);Runsource§impl NonZeroI8
impl NonZeroI8
1.64.0 (const: 1.64.0) · sourcepub const fn checked_abs(self) -> Option<NonZeroI8>
pub const fn checked_abs(self) -> Option<NonZeroI8>
Checked absolute value.
Checks for overflow and returns None if
self == NonZeroI8::MIN.
The result cannot be zero.
Example
let pos = NonZeroI8::new(1)?;
let neg = NonZeroI8::new(-1)?;
let min = NonZeroI8::new(i8::MIN)?;
assert_eq!(Some(pos), neg.checked_abs());
assert_eq!(None, min.checked_abs());Run1.64.0 (const: 1.64.0) · sourcepub 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());Run1.64.0 (const: 1.64.0) · sourcepub 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());Run1.64.0 (const: 1.64.0) · sourcepub 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());Run1.64.0 (const: 1.64.0) · sourcepub 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());Run1.71.0 (const: 1.71.0) · sourcepub const fn is_positive(self) -> bool
pub const fn is_positive(self) -> bool
1.71.0 (const: 1.71.0) · sourcepub const fn is_negative(self) -> bool
pub const fn is_negative(self) -> bool
1.71.0 (const: 1.71.0) · sourcepub const fn checked_neg(self) -> Option<NonZeroI8>
pub const fn checked_neg(self) -> Option<NonZeroI8>
1.71.0 (const: 1.71.0) · sourcepub 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));Run1.71.0 (const: 1.71.0) · sourcepub 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);Run1.71.0 (const: 1.71.0) · sourcepub 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);Runsource§impl NonZeroI8
impl NonZeroI8
1.64.0 (const: 1.64.0) · sourcepub 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));Run1.64.0 (const: 1.64.0) · sourcepub 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));Runsourcepub 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) });Run1.64.0 (const: 1.64.0) · sourcepub 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));Run1.64.0 (const: 1.64.0) · sourcepub 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));Runsource§impl NonZeroI8
impl NonZeroI8
1.70.0 · sourcepub const MIN: Self = _
pub const MIN: Self = _
The smallest value that can be represented by this non-zero
integer type,
equal to i8::MIN.
Note: While most integer types are defined for every whole
number between MIN and MAX, signed non-zero integers are
a special case. They have a “gap” at 0.
Examples
assert_eq!(NonZeroI8::MIN.get(), i8::MIN);Run1.70.0 · sourcepub const MAX: Self = _
pub const MAX: Self = _
The largest value that can be represented by this non-zero
integer type,
equal to i8::MAX.
Note: While most integer types are defined for every whole
number between MIN and MAX, signed non-zero integers are
a special case. They have a “gap” at 0.
Examples
assert_eq!(NonZeroI8::MAX.get(), i8::MAX);RunTrait Implementations§
1.45.0 · 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 more1.45.0 · source§impl BitOrAssign for NonZeroI8
impl BitOrAssign for NonZeroI8
source§fn bitor_assign(&mut self, rhs: Self)
fn bitor_assign(&mut self, rhs: Self)
|= operation. Read more1.41.0 · source§impl From<NonZeroI8> for NonZeroI128
impl From<NonZeroI8> for NonZeroI128
1.41.0 · source§impl From<NonZeroI8> for NonZeroI16
impl From<NonZeroI8> for NonZeroI16
1.41.0 · source§impl From<NonZeroI8> for NonZeroI32
impl From<NonZeroI8> for NonZeroI32
1.41.0 · source§impl From<NonZeroI8> for NonZeroI64
impl From<NonZeroI8> for NonZeroI64
1.41.0 · source§impl From<NonZeroI8> for NonZeroIsize
impl From<NonZeroI8> for NonZeroIsize
source§impl Ord for NonZeroI8
impl Ord for NonZeroI8
source§impl PartialEq for NonZeroI8
impl PartialEq for NonZeroI8
source§impl PartialOrd for NonZeroI8
impl PartialOrd 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<Self, Self::Error>
fn try_from(value: NonZeroI128) -> Result<Self, Self::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<Self, Self::Error>
fn try_from(value: NonZeroI16) -> Result<Self, Self::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<Self, Self::Error>
fn try_from(value: NonZeroI32) -> Result<Self, Self::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<Self, Self::Error>
fn try_from(value: NonZeroI64) -> Result<Self, Self::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
1.49.0 · source§impl TryFrom<NonZeroI8> for NonZeroU16
impl TryFrom<NonZeroI8> for NonZeroU16
1.49.0 · source§impl TryFrom<NonZeroI8> for NonZeroU32
impl TryFrom<NonZeroI8> for NonZeroU32
1.49.0 · source§impl TryFrom<NonZeroI8> for NonZeroU64
impl TryFrom<NonZeroI8> for NonZeroU64
1.49.0 · source§impl TryFrom<NonZeroI8> for NonZeroUsize
impl TryFrom<NonZeroI8> for NonZeroUsize
1.49.0 · source§impl TryFrom<NonZeroIsize> for NonZeroI8
impl TryFrom<NonZeroIsize> for NonZeroI8
source§fn try_from(value: NonZeroIsize) -> Result<Self, Self::Error>
fn try_from(value: NonZeroIsize) -> Result<Self, Self::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<Self, Self::Error>
fn try_from(value: NonZeroU128) -> Result<Self, Self::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<Self, Self::Error>
fn try_from(value: NonZeroU16) -> Result<Self, Self::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<Self, Self::Error>
fn try_from(value: NonZeroU32) -> Result<Self, Self::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<Self, Self::Error>
fn try_from(value: NonZeroU64) -> Result<Self, Self::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<Self, Self::Error>
fn try_from(value: NonZeroUsize) -> Result<Self, Self::Error>
Attempts to convert NonZeroUsize to NonZeroI8.