Type Alias core::num::NonZeroI64
1.34.0 · source · pub type NonZeroI64 = NonZero<i64>;
Expand description
An integer that is known not to equal zero.
This enables some memory layout optimization.
For example, Option<NonZeroI64>
is the same size as i64
:
use std::mem::size_of;
assert_eq!(size_of::<Option<core::num::NonZeroI64>>(), size_of::<i64>());
Run§Layout
NonZeroI64
is guaranteed to have the same layout and bit validity as i64
with the exception that 0
is not a valid instance.
Option<NonZeroI64>
is guaranteed to be compatible with i64
,
including in FFI.
Thanks to the null pointer optimization,
NonZeroI64
and Option<NonZeroI64>
are guaranteed to have the same size and alignment:
use std::num::NonZeroI64;
assert_eq!(size_of::<NonZeroI64>(), size_of::<Option<NonZeroI64>>());
assert_eq!(align_of::<NonZeroI64>(), align_of::<Option<NonZeroI64>>());
RunAliased Type§
struct NonZeroI64(/* private fields */);
Implementations§
source§impl NonZeroI64
impl NonZeroI64
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::NonZeroI64::new(-1i64).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::NonZeroI64::new(0b0101000).unwrap();
assert_eq!(n.trailing_zeros(), 3);
Runconst: unstable · sourcepub fn count_ones(self) -> NonZero<u32>
🔬This is a nightly-only experimental API. (non_zero_count_ones
#120287)
pub fn count_ones(self) -> NonZero<u32>
non_zero_count_ones
#120287)Returns the number of ones in the binary representation of self
.
§Examples
Basic usage:
#![feature(generic_nonzero, non_zero_count_ones)]
let a = NonZero::<i64>::new(0b100_0000)?;
let b = NonZero::<i64>::new(0b100_0011)?;
assert_eq!(a.count_ones(), NonZero::new(1)?);
assert_eq!(b.count_ones(), NonZero::new(3)?);
Run1.70.0 · sourcepub const MIN: Self = _
pub const MIN: Self = _
The smallest value that can be represented by this non-zero
integer type,
equal to i64::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!(NonZeroI64::MIN.get(), i64::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 i64::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!(NonZeroI64::MAX.get(), i64::MAX);
Run1.64.0 (const: 1.64.0) · sourcepub const fn checked_abs(self) -> Option<Self>
pub const fn checked_abs(self) -> Option<Self>
Checked absolute value.
Checks for overflow and returns None
if
self == NonZeroI64::MIN
.
The result cannot be zero.
§Example
let pos = NonZeroI64::new(1)?;
let neg = NonZeroI64::new(-1)?;
let min = NonZeroI64::new(i64::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) -> (Self, bool)
pub const fn overflowing_abs(self) -> (Self, bool)
Computes the absolute value of self,
with overflow information, see
i64::overflowing_abs
.
§Example
let pos = NonZeroI64::new(1)?;
let neg = NonZeroI64::new(-1)?;
let min = NonZeroI64::new(i64::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) -> Self
pub const fn saturating_abs(self) -> Self
Saturating absolute value, see
i64::saturating_abs
.
§Example
let pos = NonZeroI64::new(1)?;
let neg = NonZeroI64::new(-1)?;
let min = NonZeroI64::new(i64::MIN)?;
let min_plus = NonZeroI64::new(i64::MIN + 1)?;
let max = NonZeroI64::new(i64::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) -> Self
pub const fn wrapping_abs(self) -> Self
Wrapping absolute value, see
i64::wrapping_abs
.
§Example
let pos = NonZeroI64::new(1)?;
let neg = NonZeroI64::new(-1)?;
let min = NonZeroI64::new(i64::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) -> NonZeroU64
pub const fn unsigned_abs(self) -> NonZeroU64
Computes the absolute value of self without any wrapping or panicking.
§Example
let u_pos = NonZeroU64::new(1)?;
let i_pos = NonZeroI64::new(1)?;
let i_neg = NonZeroI64::new(-1)?;
let i_min = NonZeroI64::new(i64::MIN)?;
let u_max = NonZeroU64::new(u64::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<Self>
pub const fn checked_neg(self) -> Option<Self>
1.71.0 (const: 1.71.0) · sourcepub const fn overflowing_neg(self) -> (Self, bool)
pub const fn overflowing_neg(self) -> (Self, bool)
Negates self, overflowing if this is equal to the minimum value.
See i64::overflowing_neg
for documentation on overflow behaviour.
§Example
let pos_five = NonZeroI64::new(5)?;
let neg_five = NonZeroI64::new(-5)?;
let min = NonZeroI64::new(i64::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) -> Self
pub const fn saturating_neg(self) -> Self
Saturating negation. Computes -self
,
returning NonZeroI64::MAX
if self == NonZeroI64::MIN
instead of overflowing.
§Example
let pos_five = NonZeroI64::new(5)?;
let neg_five = NonZeroI64::new(-5)?;
let min = NonZeroI64::new(i64::MIN)?;
let min_plus_one = NonZeroI64::new(i64::MIN + 1)?;
let max = NonZeroI64::new(i64::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) -> Self
pub const fn wrapping_neg(self) -> Self
Wrapping (modular) negation. Computes -self
, wrapping around at the boundary
of the type.
See i64::wrapping_neg
for documentation on overflow behaviour.
§Example
let pos_five = NonZeroI64::new(5)?;
let neg_five = NonZeroI64::new(-5)?;
let min = NonZeroI64::new(i64::MIN)?;
assert_eq!(pos_five.wrapping_neg(), neg_five);
assert_eq!(min.wrapping_neg(), min);
Run1.64.0 (const: 1.64.0) · sourcepub const fn checked_mul(self, other: Self) -> Option<Self>
pub const fn checked_mul(self, other: Self) -> Option<Self>
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 = NonZeroI64::new(2)?;
let four = NonZeroI64::new(4)?;
let max = NonZeroI64::new(i64::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: Self) -> Self
pub const fn saturating_mul(self, other: Self) -> Self
Multiplies two non-zero integers together.
Return NonZeroI64::MAX
on overflow.
§Examples
let two = NonZeroI64::new(2)?;
let four = NonZeroI64::new(4)?;
let max = NonZeroI64::new(i64::MAX)?;
assert_eq!(four, two.saturating_mul(two));
assert_eq!(max, four.saturating_mul(max));
Runsourcepub const unsafe fn unchecked_mul(self, other: Self) -> Self
🔬This is a nightly-only experimental API. (nonzero_ops
#84186)
pub const unsafe fn unchecked_mul(self, other: Self) -> Self
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 > i64::MAX
, or self * rhs < i64::MIN
.
§Examples
#![feature(nonzero_ops)]
let two = NonZeroI64::new(2)?;
let four = NonZeroI64::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<Self>
pub const fn checked_pow(self, other: u32) -> Option<Self>
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 = NonZeroI64::new(3)?;
let twenty_seven = NonZeroI64::new(27)?;
let half_max = NonZeroI64::new(i64::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) -> Self
pub const fn saturating_pow(self, other: u32) -> Self
Raise non-zero value to an integer power.
Return NonZeroI64::MIN
or NonZeroI64::MAX
on overflow.
§Examples
let three = NonZeroI64::new(3)?;
let twenty_seven = NonZeroI64::new(27)?;
let max = NonZeroI64::new(i64::MAX)?;
assert_eq!(twenty_seven, three.saturating_pow(3));
assert_eq!(max, max.saturating_pow(3));
Run