pub struct NonZeroI8(_);
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.
Implementations§
source§impl NonZeroI8
impl NonZeroI8
const: 1.34.0 · sourcepub 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) · 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);
1.53.0 (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);
source§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>
1.64.0 (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());
1.64.0 (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());
1.64.0 (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());
1.64.0 (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());
sourcepub const fn is_negative(self) -> bool
🔬This is a nightly-only experimental API. (nonzero_negation_ops
)
pub const fn is_negative(self) -> bool
nonzero_negation_ops
)Returns true
if self
is negative and false
if the
number is positive.
Example
#![feature(nonzero_negation_ops)]
let pos_five = NonZeroI8::new(5)?;
let neg_five = NonZeroI8::new(-5)?;
assert!(neg_five.is_negative());
assert!(!pos_five.is_negative());
sourcepub const fn checked_neg(self) -> Option<NonZeroI8>
🔬This is a nightly-only experimental API. (nonzero_negation_ops
)
pub const fn checked_neg(self) -> Option<NonZeroI8>
nonzero_negation_ops
)Checked negation. Computes -self
, returning None
if self == i32::MIN
.
Example
#![feature(nonzero_negation_ops)]
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);
sourcepub const fn overflowing_neg(self) -> (NonZeroI8, bool)
🔬This is a nightly-only experimental API. (nonzero_negation_ops
)
pub const fn overflowing_neg(self) -> (NonZeroI8, bool)
nonzero_negation_ops
)Negates self, overflowing if this is equal to the minimum value.
See i8::overflowing_neg
for documentation on overflow behaviour.
Example
#![feature(nonzero_negation_ops)]
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));
sourcepub const fn saturating_neg(self) -> NonZeroI8
🔬This is a nightly-only experimental API. (nonzero_negation_ops
)
pub const fn saturating_neg(self) -> NonZeroI8
nonzero_negation_ops
)Saturating negation. Computes -self
, returning MAX
if
self == i32::MIN
instead of overflowing.
Example
#![feature(nonzero_negation_ops)]
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);
sourcepub const fn wrapping_neg(self) -> NonZeroI8
🔬This is a nightly-only experimental API. (nonzero_negation_ops
)
pub const fn wrapping_neg(self) -> NonZeroI8
nonzero_negation_ops
)Wrapping (modular) negation. Computes -self
, wrapping around at the boundary
of the type.
See i8::wrapping_neg
for documentation on overflow behaviour.
Example
#![feature(nonzero_negation_ops)]
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) · 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));
1.64.0 (const: 1.64.0) · sourcepub const fn saturating_mul(self, other: NonZeroI8) -> NonZeroI8
pub const fn saturating_mul(self, other: NonZeroI8) -> NonZeroI8
sourcepub const unsafe fn unchecked_mul(self, other: NonZeroI8) -> NonZeroI8
🔬This is a nightly-only experimental API. (nonzero_ops
)
pub const unsafe fn unchecked_mul(self, other: NonZeroI8) -> NonZeroI8
nonzero_ops
)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) · 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));
1.64.0 (const: 1.64.0) · sourcepub const fn saturating_pow(self, other: u32) -> NonZeroI8
pub const fn saturating_pow(self, other: u32) -> NonZeroI8
Trait Implementations§
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
.