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Struct std::num::NonZeroI8
pub struct NonZeroI8(/* private fields */);
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>>());
Implementations
impl 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.
pub const fn new(n: i8) -> Option<NonZeroI8>
Creates a non-zero if the given value is not zero.
pub const fn get(self) -> i8
Returns the value as a primitive type.
impl NonZeroI8
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);
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);
impl NonZeroI8
pub const fn abs(self) -> NonZeroI8
Computes the absolute value of self. See i8::abs
for documentation on overflow behaviour.
Example
let pos = NonZeroI8::new(1)?;
let neg = NonZeroI8::new(-1)?;
assert_eq!(pos, pos.abs());
assert_eq!(pos, neg.abs());
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());
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());
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());
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());
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());
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());
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());
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);
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));
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);
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);
impl 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));
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));
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) });
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));
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));
impl NonZeroI8
pub const MIN: NonZeroI8 = _
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);
pub const MAX: NonZeroI8 = _
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);
impl NonZeroI8
Trait Implementations
impl Binary for NonZeroI8
fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
impl BitOr<NonZeroI8> for i8
type Output = NonZeroI8
|
operator.
fn bitor(self, rhs: NonZeroI8) -> <i8 as BitOr<NonZeroI8>>::Output
|
operation. Read more
impl BitOr<i8> for NonZeroI8
type Output = NonZeroI8
|
operator.
fn bitor(self, rhs: i8) -> <NonZeroI8 as BitOr<i8>>::Output
|
operation. Read more
impl BitOr for NonZeroI8
type Output = NonZeroI8
|
operator.
fn bitor(self, rhs: NonZeroI8) -> <NonZeroI8 as BitOr>::Output
|
operation. Read more
impl BitOrAssign<i8> for NonZeroI8
impl BitOrAssign for NonZeroI8
impl Clone for NonZeroI8
fn clone(&self) -> NonZeroI8
fn clone_from(&mut self, source: &Self)
source
. Read more
impl Debug for NonZeroI8
fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
impl Display for NonZeroI8
fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
impl From<NonZeroI8> for NonZeroI128
fn from(small: NonZeroI8) -> NonZeroI128
Converts NonZeroI8
to NonZeroI128
losslessly.
impl From<NonZeroI8> for NonZeroI16
fn from(small: NonZeroI8) -> NonZeroI16
Converts NonZeroI8
to NonZeroI16
losslessly.
impl From<NonZeroI8> for NonZeroI32
fn from(small: NonZeroI8) -> NonZeroI32
Converts NonZeroI8
to NonZeroI32
losslessly.
impl From<NonZeroI8> for NonZeroI64
fn from(small: NonZeroI8) -> NonZeroI64
Converts NonZeroI8
to NonZeroI64
losslessly.
impl From<NonZeroI8> for NonZeroIsize
fn from(small: NonZeroI8) -> NonZeroIsize
Converts NonZeroI8
to NonZeroIsize
losslessly.
impl From<NonZeroI8> for i8
fn from(nonzero: NonZeroI8) -> i8
Converts a NonZeroI8
into an i8
impl FromStr for NonZeroI8
type Err = ParseIntError
fn from_str(src: &str) -> Result<NonZeroI8, <NonZeroI8 as FromStr>::Err>
s
to return a value of this type. Read more
impl Hash for NonZeroI8
fn hash<__H>(&self, state: &mut __H)
where
__H: Hasher,
fn hash_slice<H>(data: &[Self], state: &mut H)
where
H: Hasher,
Self: Sized,
impl LowerHex for NonZeroI8
fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
impl Neg for &NonZeroI8
type Output = <NonZeroI8 as Neg>::Output
-
operator.
fn neg(self) -> <NonZeroI8 as Neg>::Output
-
operation. Read more
impl Neg for NonZeroI8
type Output = NonZeroI8
-
operator.
fn neg(self) -> NonZeroI8
-
operation. Read more
impl Octal for NonZeroI8
fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
impl Ord for NonZeroI8
fn cmp(&self, other: &NonZeroI8) -> Ordering
fn max(self, other: Self) -> Self
where
Self: Sized,
fn min(self, other: Self) -> Self
where
Self: Sized,
fn clamp(self, min: Self, max: Self) -> Self
where
Self: Sized + PartialOrd,
impl PartialEq for NonZeroI8
fn eq(&self, other: &NonZeroI8) -> bool
self
and other
values to be equal, and is used by ==
.
fn ne(&self, other: &Rhs) -> bool
!=
. The default implementation is almost always sufficient, and should not be overridden without very good reason.
impl PartialOrd for NonZeroI8
fn partial_cmp(&self, other: &NonZeroI8) -> Option<Ordering>
fn lt(&self, other: &Rhs) -> bool
fn le(&self, other: &Rhs) -> bool
self
and other
) and is used by the <=
operator. Read more
fn gt(&self, other: &Rhs) -> bool
fn ge(&self, other: &Rhs) -> bool
self
and other
) and is used by the >=
operator. Read more
impl TryFrom<NonZeroI128> for NonZeroI8
fn try_from(
value: NonZeroI128
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI128>>::Error>
Attempts to convert NonZeroI128
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroI16> for NonZeroI8
fn try_from(
value: NonZeroI16
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI16>>::Error>
Attempts to convert NonZeroI16
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroI32> for NonZeroI8
fn try_from(
value: NonZeroI32
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI32>>::Error>
Attempts to convert NonZeroI32
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroI64> for NonZeroI8
fn try_from(
value: NonZeroI64
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroI64>>::Error>
Attempts to convert NonZeroI64
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroI8> for NonZeroU128
fn try_from(
value: NonZeroI8
) -> Result<NonZeroU128, <NonZeroU128 as TryFrom<NonZeroI8>>::Error>
Attempts to convert NonZeroI8
to NonZeroU128
.
type Error = TryFromIntError
impl TryFrom<NonZeroI8> for NonZeroU16
fn try_from(
value: NonZeroI8
) -> Result<NonZeroU16, <NonZeroU16 as TryFrom<NonZeroI8>>::Error>
Attempts to convert NonZeroI8
to NonZeroU16
.
type Error = TryFromIntError
impl TryFrom<NonZeroI8> for NonZeroU32
fn try_from(
value: NonZeroI8
) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroI8>>::Error>
Attempts to convert NonZeroI8
to NonZeroU32
.
type Error = TryFromIntError
impl TryFrom<NonZeroI8> for NonZeroU64
fn try_from(
value: NonZeroI8
) -> Result<NonZeroU64, <NonZeroU64 as TryFrom<NonZeroI8>>::Error>
Attempts to convert NonZeroI8
to NonZeroU64
.
type Error = TryFromIntError
impl TryFrom<NonZeroI8> for NonZeroU8
fn try_from(
value: NonZeroI8
) -> Result<NonZeroU8, <NonZeroU8 as TryFrom<NonZeroI8>>::Error>
Attempts to convert NonZeroI8
to NonZeroU8
.
type Error = TryFromIntError
impl TryFrom<NonZeroI8> for NonZeroUsize
fn try_from(
value: NonZeroI8
) -> Result<NonZeroUsize, <NonZeroUsize as TryFrom<NonZeroI8>>::Error>
Attempts to convert NonZeroI8
to NonZeroUsize
.
type Error = TryFromIntError
impl TryFrom<NonZeroIsize> for NonZeroI8
fn try_from(
value: NonZeroIsize
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroIsize>>::Error>
Attempts to convert NonZeroIsize
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroU128> for NonZeroI8
fn try_from(
value: NonZeroU128
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU128>>::Error>
Attempts to convert NonZeroU128
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroU16> for NonZeroI8
fn try_from(
value: NonZeroU16
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU16>>::Error>
Attempts to convert NonZeroU16
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroU32> for NonZeroI8
fn try_from(
value: NonZeroU32
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU32>>::Error>
Attempts to convert NonZeroU32
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroU64> for NonZeroI8
fn try_from(
value: NonZeroU64
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU64>>::Error>
Attempts to convert NonZeroU64
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroU8> for NonZeroI8
fn try_from(
value: NonZeroU8
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroU8>>::Error>
Attempts to convert NonZeroU8
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<NonZeroUsize> for NonZeroI8
fn try_from(
value: NonZeroUsize
) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<NonZeroUsize>>::Error>
Attempts to convert NonZeroUsize
to NonZeroI8
.
type Error = TryFromIntError
impl TryFrom<i8> for NonZeroI8
fn try_from(value: i8) -> Result<NonZeroI8, <NonZeroI8 as TryFrom<i8>>::Error>
Attempts to convert i8
to NonZeroI8
.
type Error = TryFromIntError
impl UpperHex for NonZeroI8
fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>
impl Copy for NonZeroI8
impl Eq for NonZeroI8
impl StructuralEq for NonZeroI8
impl StructuralPartialEq for NonZeroI8
Auto Trait Implementations
impl RefUnwindSafe for NonZeroI8
impl Send for NonZeroI8
impl Sync for NonZeroI8
impl Unpin for NonZeroI8
impl UnwindSafe for NonZeroI8
Blanket Implementations
impl<T> Any for T
where
T: 'static + ?Sized,
impl<T> Borrow<T> for T
where
T: ?Sized,
impl<T> BorrowMut<T> for T
where
T: ?Sized,
impl<T> From<T> for T
fn from(t: T) -> T
Returns the argument unchanged.
impl<T, U> Into<U> for T
where
U: From<T>,
fn into(self) -> U
Calls U::from(self)
.
That is, this conversion is whatever the implementation of From<T> for U
chooses to do.
impl<T> ToOwned for T
where
T: Clone,
type Owned = T
fn to_owned(&self) -> T
fn clone_into(&self, target: &mut T)
impl<T> ToString for T
where
T: Display + ?Sized,
impl<T, U> TryFrom<U> for T
where
U: Into<T>,
type Error = Infallible
fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>
impl<T, U> TryInto<U> for T
where
U: TryFrom<T>,
type Error = <U as TryFrom<T>>::Error
fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>
© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/num/struct.NonZeroI8.html