Primitive Type u641.0.0[−]
Expand description
The 64-bit unsigned integer type.
Implementations
Converts a string slice in a given base to an integer.
The string is expected to be an optional +
sign
followed by digits.
Leading and trailing whitespace represent an error.
Digits are a subset of these characters, depending on radix
:
0-9
a-z
A-Z
Panics
This function panics if radix
is not in the range from 2 to 36.
Examples
Basic usage:
assert_eq!(u64::from_str_radix("A", 16), Ok(10));
RunShifts the bits to the right by a specified amount, n
,
wrapping the truncated bits to the beginning of the resulting
integer.
Please note this isn’t the same operation as the >>
shifting operator!
Examples
Basic usage:
let n = 0x6e10aau64;
let m = 0xaa00000000006e1;
assert_eq!(n.rotate_right(12), m);
RunReverses the order of bits in the integer. The least significant bit becomes the most significant bit, second least-significant bit becomes second most-significant bit, etc.
Examples
Basic usage:
let n = 0x1234567890123456u64;
let m = n.reverse_bits();
assert_eq!(m, 0x6a2c48091e6a2c48);
assert_eq!(0, 0u64.reverse_bits());
RunConverts an integer from little endian to the target’s endianness.
On little endian this is a no-op. On big endian the bytes are swapped.
Examples
Basic usage:
let n = 0x1Au64;
if cfg!(target_endian = "little") {
assert_eq!(u64::from_le(n), n)
} else {
assert_eq!(u64::from_le(n), n.swap_bytes())
}
Run🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
Unchecked integer addition. Computes self + rhs
, assuming overflow
cannot occur.
Safety
This results in undefined behavior when
self + rhs > u64::MAX
or self + rhs < u64::MIN
,
i.e. when checked_add
would return None
.
🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
Unchecked integer subtraction. Computes self - rhs
, assuming overflow
cannot occur.
Safety
This results in undefined behavior when
self - rhs > u64::MAX
or self - rhs < u64::MIN
,
i.e. when checked_sub
would return None
.
🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
Unchecked integer multiplication. Computes self * rhs
, assuming overflow
cannot occur.
Safety
This results in undefined behavior when
self * rhs > u64::MAX
or self * rhs < u64::MIN
,
i.e. when checked_mul
would return None
.
Returns the logarithm of the number with respect to an arbitrary base.
This method might not be optimized owing to implementation details;
log2
can produce results more efficiently for base 2, and log10
can produce results more efficiently for base 10.
Panics
When the number is negative, zero, or if the base is not at least 2; it panics in debug mode and the return value is wrapped to 0 in release mode (the only situation in which the method can return 0).
Examples
#![feature(int_log)]
assert_eq!(5u64.log(5), 1);
RunReturns the logarithm of the number with respect to an arbitrary base.
Returns None
if the number is zero, or if the base is not at least 2.
This method might not be optimized owing to implementation details;
checked_log2
can produce results more efficiently for base 2, and
checked_log10
can produce results more efficiently for base 10.
Examples
#![feature(int_log)]
assert_eq!(5u64.checked_log(5), Some(1));
Run🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
Unchecked shift left. Computes self << rhs
, assuming that
rhs
is less than the number of bits in self
.
Safety
This results in undefined behavior if rhs
is larger than
or equal to the number of bits in self
,
i.e. when checked_shl
would return None
.
🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
🔬 This is a nightly-only experimental API. (unchecked_math
#85122)
niche optimization path
Unchecked shift right. Computes self >> rhs
, assuming that
rhs
is less than the number of bits in self
.
Safety
This results in undefined behavior if rhs
is larger than
or equal to the number of bits in self
,
i.e. when checked_shr
would return None
.
Wrapping (modular) multiplication. Computes self * rhs
, wrapping around at the boundary of the type.
Examples
Basic usage:
Please note that this example is shared between integer types.
Which explains why u8
is used here.
assert_eq!(10u8.wrapping_mul(12), 120);
assert_eq!(25u8.wrapping_mul(12), 44);
RunWrapping (modular) division. Computes self / rhs
.
Wrapped division on unsigned types is just normal division.
There’s no way wrapping could ever happen.
This function exists, so that all operations
are accounted for in the wrapping operations.
Examples
Basic usage:
assert_eq!(100u64.wrapping_div(10), 10);
RunWrapping Euclidean division. Computes self.div_euclid(rhs)
.
Wrapped division on unsigned types is just normal division.
There’s no way wrapping could ever happen.
This function exists, so that all operations
are accounted for in the wrapping operations.
Since, for the positive integers, all common
definitions of division are equal, this
is exactly equal to self.wrapping_div(rhs)
.
Examples
Basic usage:
assert_eq!(100u64.wrapping_div_euclid(10), 10);
RunWrapping (modular) remainder. Computes self % rhs
.
Wrapped remainder calculation on unsigned types is
just the regular remainder calculation.
There’s no way wrapping could ever happen.
This function exists, so that all operations
are accounted for in the wrapping operations.
Examples
Basic usage:
assert_eq!(100u64.wrapping_rem(10), 0);
RunWrapping Euclidean modulo. Computes self.rem_euclid(rhs)
.
Wrapped modulo calculation on unsigned types is
just the regular remainder calculation.
There’s no way wrapping could ever happen.
This function exists, so that all operations
are accounted for in the wrapping operations.
Since, for the positive integers, all common
definitions of division are equal, this
is exactly equal to self.wrapping_rem(rhs)
.
Examples
Basic usage:
assert_eq!(100u64.wrapping_rem_euclid(10), 0);
RunWrapping (modular) negation. Computes -self
,
wrapping around at the boundary of the type.
Since unsigned types do not have negative equivalents
all applications of this function will wrap (except for -0
).
For values smaller than the corresponding signed type’s maximum
the result is the same as casting the corresponding signed value.
Any larger values are equivalent to MAX + 1 - (val - MAX - 1)
where
MAX
is the corresponding signed type’s maximum.
Examples
Basic usage:
Please note that this example is shared between integer types.
Which explains why i8
is used here.
assert_eq!(100i8.wrapping_neg(), -100);
assert_eq!((-128i8).wrapping_neg(), -128);
RunPanic-free bitwise shift-left; yields self << mask(rhs)
,
where mask
removes any high-order bits of rhs
that
would cause the shift to exceed the bitwidth of the type.
Note that this is not the same as a rotate-left; the
RHS of a wrapping shift-left is restricted to the range
of the type, rather than the bits shifted out of the LHS
being returned to the other end. The primitive integer
types all implement a rotate_left
function,
which may be what you want instead.
Examples
Basic usage:
assert_eq!(1u64.wrapping_shl(7), 128);
assert_eq!(1u64.wrapping_shl(128), 1);
RunPanic-free bitwise shift-right; yields self >> mask(rhs)
,
where mask
removes any high-order bits of rhs
that
would cause the shift to exceed the bitwidth of the type.
Note that this is not the same as a rotate-right; the
RHS of a wrapping shift-right is restricted to the range
of the type, rather than the bits shifted out of the LHS
being returned to the other end. The primitive integer
types all implement a rotate_right
function,
which may be what you want instead.
Examples
Basic usage:
assert_eq!(128u64.wrapping_shr(7), 1);
assert_eq!(128u64.wrapping_shr(128), 128);
RunCalculates self
+ rhs
Returns a tuple of the addition along with a boolean indicating whether an arithmetic overflow would occur. If an overflow would have occurred then the wrapped value is returned.
Examples
Basic usage
assert_eq!(5u64.overflowing_add(2), (7, false));
assert_eq!(u64::MAX.overflowing_add(1), (0, true));
RunCalculates self
- rhs
Returns a tuple of the subtraction along with a boolean indicating whether an arithmetic overflow would occur. If an overflow would have occurred then the wrapped value is returned.
Examples
Basic usage
assert_eq!(5u64.overflowing_sub(2), (3, false));
assert_eq!(0u64.overflowing_sub(1), (u64::MAX, true));
RunCalculates the multiplication of self
and rhs
.
Returns a tuple of the multiplication along with a boolean indicating whether an arithmetic overflow would occur. If an overflow would have occurred then the wrapped value is returned.
Examples
Basic usage:
Please note that this example is shared between integer types.
Which explains why u32
is used here.
assert_eq!(5u32.overflowing_mul(2), (10, false));
assert_eq!(1_000_000_000u32.overflowing_mul(10), (1410065408, true));
RunCalculates the divisor when self
is divided by rhs
.
Returns a tuple of the divisor along with a boolean indicating
whether an arithmetic overflow would occur. Note that for unsigned
integers overflow never occurs, so the second value is always
false
.
Panics
This function will panic if rhs
is 0.
Examples
Basic usage
assert_eq!(5u64.overflowing_div(2), (2, false));
RunCalculates the quotient of Euclidean division self.div_euclid(rhs)
.
Returns a tuple of the divisor along with a boolean indicating
whether an arithmetic overflow would occur. Note that for unsigned
integers overflow never occurs, so the second value is always
false
.
Since, for the positive integers, all common
definitions of division are equal, this
is exactly equal to self.overflowing_div(rhs)
.
Panics
This function will panic if rhs
is 0.
Examples
Basic usage
assert_eq!(5u64.overflowing_div_euclid(2), (2, false));
RunCalculates the remainder when self
is divided by rhs
.
Returns a tuple of the remainder after dividing along with a boolean
indicating whether an arithmetic overflow would occur. Note that for
unsigned integers overflow never occurs, so the second value is
always false
.
Panics
This function will panic if rhs
is 0.
Examples
Basic usage
assert_eq!(5u64.overflowing_rem(2), (1, false));
RunCalculates the remainder self.rem_euclid(rhs)
as if by Euclidean division.
Returns a tuple of the modulo after dividing along with a boolean
indicating whether an arithmetic overflow would occur. Note that for
unsigned integers overflow never occurs, so the second value is
always false
.
Since, for the positive integers, all common
definitions of division are equal, this operation
is exactly equal to self.overflowing_rem(rhs)
.
Panics
This function will panic if rhs
is 0.
Examples
Basic usage
assert_eq!(5u64.overflowing_rem_euclid(2), (1, false));
RunNegates self in an overflowing fashion.
Returns !self + 1
using wrapping operations to return the value
that represents the negation of this unsigned value. Note that for
positive unsigned values overflow always occurs, but negating 0 does
not overflow.
Examples
Basic usage
assert_eq!(0u64.overflowing_neg(), (0, false));
assert_eq!(2u64.overflowing_neg(), (-2i32 as u64, true));
RunShifts self left by rhs
bits.
Returns a tuple of the shifted version of self along with a boolean indicating whether the shift value was larger than or equal to the number of bits. If the shift value is too large, then value is masked (N-1) where N is the number of bits, and this value is then used to perform the shift.
Examples
Basic usage
assert_eq!(0x1u64.overflowing_shl(4), (0x10, false));
assert_eq!(0x1u64.overflowing_shl(132), (0x10, true));
RunShifts self right by rhs
bits.
Returns a tuple of the shifted version of self along with a boolean indicating whether the shift value was larger than or equal to the number of bits. If the shift value is too large, then value is masked (N-1) where N is the number of bits, and this value is then used to perform the shift.
Examples
Basic usage
assert_eq!(0x10u64.overflowing_shr(4), (0x1, false));
assert_eq!(0x10u64.overflowing_shr(132), (0x1, true));
RunCalculates the least remainder of self (mod rhs)
.
Since, for the positive integers, all common
definitions of division are equal, this
is exactly equal to self % rhs
.
Panics
This function will panic if rhs
is 0.
Examples
Basic usage:
assert_eq!(7u64.rem_euclid(4), 3); // or any other integer type
RunReturns the smallest power of two greater than or equal to self
.
When return value overflows (i.e., self > (1 << (N-1))
for type
uN
), it panics in debug mode and return value is wrapped to 0 in
release mode (the only situation in which method can return 0).
Examples
Basic usage:
assert_eq!(2u64.next_power_of_two(), 2);
assert_eq!(3u64.next_power_of_two(), 4);
RunReturns the smallest power of two greater than or equal to n
. If
the next power of two is greater than the type’s maximum value,
None
is returned, otherwise the power of two is wrapped in Some
.
Examples
Basic usage:
assert_eq!(2u64.checked_next_power_of_two(), Some(2));
assert_eq!(3u64.checked_next_power_of_two(), Some(4));
assert_eq!(u64::MAX.checked_next_power_of_two(), None);
Run🔬 This is a nightly-only experimental API. (wrapping_next_power_of_two
#32463)
needs decision on wrapping behaviour
🔬 This is a nightly-only experimental API. (wrapping_next_power_of_two
#32463)
needs decision on wrapping behaviour
Returns the smallest power of two greater than or equal to n
. If
the next power of two is greater than the type’s maximum value,
the return value is wrapped to 0
.
Examples
Basic usage:
#![feature(wrapping_next_power_of_two)]
assert_eq!(2u64.wrapping_next_power_of_two(), 2);
assert_eq!(3u64.wrapping_next_power_of_two(), 4);
assert_eq!(u64::MAX.wrapping_next_power_of_two(), 0);
RunReturn the memory representation of this integer as a byte array in native byte order.
As the target platform’s native endianness is used, portable code
should use to_be_bytes
or to_le_bytes
, as appropriate,
instead.
Examples
let bytes = 0x1234567890123456u64.to_ne_bytes();
assert_eq!(
bytes,
if cfg!(target_endian = "big") {
[0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56]
} else {
[0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]
}
);
RunCreate a native endian integer value from its representation as a byte array in big endian.
Examples
let value = u64::from_be_bytes([0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56]);
assert_eq!(value, 0x1234567890123456);
RunWhen starting from a slice rather than an array, fallible conversion APIs can be used:
use std::convert::TryInto;
fn read_be_u64(input: &mut &[u8]) -> u64 {
let (int_bytes, rest) = input.split_at(std::mem::size_of::<u64>());
*input = rest;
u64::from_be_bytes(int_bytes.try_into().unwrap())
}
RunCreate a native endian integer value from its representation as a byte array in little endian.
Examples
let value = u64::from_le_bytes([0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]);
assert_eq!(value, 0x1234567890123456);
RunWhen starting from a slice rather than an array, fallible conversion APIs can be used:
use std::convert::TryInto;
fn read_le_u64(input: &mut &[u8]) -> u64 {
let (int_bytes, rest) = input.split_at(std::mem::size_of::<u64>());
*input = rest;
u64::from_le_bytes(int_bytes.try_into().unwrap())
}
RunCreate a native endian integer value from its memory representation as a byte array in native endianness.
As the target platform’s native endianness is used, portable code
likely wants to use from_be_bytes
or from_le_bytes
, as
appropriate instead.
Examples
let value = u64::from_ne_bytes(if cfg!(target_endian = "big") {
[0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56]
} else {
[0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]
});
assert_eq!(value, 0x1234567890123456);
RunWhen starting from a slice rather than an array, fallible conversion APIs can be used:
use std::convert::TryInto;
fn read_ne_u64(input: &mut &[u8]) -> u64 {
let (int_bytes, rest) = input.split_at(std::mem::size_of::<u64>());
*input = rest;
u64::from_ne_bytes(int_bytes.try_into().unwrap())
}
Run👎 Deprecating in a future Rust version: replaced by the MIN
associated constant on this type
replaced by the MIN
associated constant on this type
New code should prefer to use
u64::MIN
instead.
Returns the smallest value that can be represented by this integer type.
Trait Implementations
Performs the +=
operation. Read more
Performs the +=
operation. Read more
Performs the &=
operation. Read more
Performs the &=
operation. Read more
type Output = NonZeroU64
type Output = NonZeroU64
The resulting type after applying the |
operator.
Performs the |
operation. Read more
Performs the |=
operation. Read more
Performs the |=
operation. Read more
Performs the ^=
operation. Read more
Performs the ^=
operation. Read more
This operation rounds towards zero, truncating any fractional part of the exact result.
Panics
This operation will panic if other == 0
.
Performs the /=
operation. Read more
Performs the /=
operation. Read more
Converts a NonZeroU64
into an u64
type Err = ParseIntError
type Err = ParseIntError
The associated error which can be returned from parsing.
Performs the *=
operation. Read more
Performs the *=
operation. Read more
This method returns an ordering between self
and other
values if one exists. Read more
This method tests less than (for self
and other
) and is used by the <
operator. Read more
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
This method tests greater than or equal to (for self
and other
) and is used by the >=
operator. Read more
This operation satisfies n % d == n - (n / d) * d
. The
result has the same sign as the left operand.
Panics
This operation will panic if other == 0
.
Performs the %=
operation. Read more
Performs the %=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the <<=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
Performs the >>=
operation. Read more
🔬 This is a nightly-only experimental API. (step_trait
#42168)
recently redesigned
Returns the value that would be obtained by taking the successor
of self
count
times. Read more
🔬 This is a nightly-only experimental API. (step_trait
#42168)
recently redesigned
Returns the value that would be obtained by taking the predecessor
of self
count
times. Read more
🔬 This is a nightly-only experimental API. (step_trait
#42168)
recently redesigned
Returns the value that would be obtained by taking the successor
of self
count
times. Read more
🔬 This is a nightly-only experimental API. (step_trait
#42168)
recently redesigned
Returns the value that would be obtained by taking the predecessor
of self
count
times. Read more
🔬 This is a nightly-only experimental API. (step_trait
#42168)
recently redesigned
Returns the number of successor steps required to get from start
to end
. Read more
Performs the -=
operation. Read more
Performs the -=
operation. Read more
Try to create the target number type from a source number type. This returns an error if the source value is outside of the range of the target type.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Try to create the target number type from a source number type. This returns an error if the source value is outside of the range of the target type.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Try to create the target number type from a source number type. This returns an error if the source value is outside of the range of the target type.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Try to create the target number type from a source number type. This returns an error if the source value is outside of the range of the target type.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Try to create the target number type from a source number type. This returns an error if the source value is outside of the range of the target type.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Try to create the target number type from a source number type. This returns an error if the source value is outside of the range of the target type.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Try to create the target number type from a source number type. This returns an error if the source value is outside of the range of the target type.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Try to create the target number type from a source number type. This returns an error if the source value is outside of the range of the target type.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Auto Trait Implementations
impl RefUnwindSafe for u64
impl UnwindSafe for u64
Blanket Implementations
Mutably borrows from an owned value. Read more