Struct core::num::NonZeroUsize 1.28.0[−][src]
#[repr(transparent)]pub struct NonZeroUsize(_);
Expand description
An integer that is known not to equal zero.
This enables some memory layout optimization.
For example, Option<NonZeroUsize> is the same size as usize:
use std::mem::size_of; assert_eq!(size_of::<Option<core::num::NonZeroUsize>>(), size_of::<usize>());Run
Implementations
Creates a non-zero if the given value is not zero.
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::NonZeroUsize::new(usize::MAX).unwrap(); assert_eq!(n.leading_zeros(), 0);Run
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::NonZeroUsize::new(0b0101000).unwrap(); assert_eq!(n.trailing_zeros(), 3);Run
Returns true if and only if self == (1 << k) for some k.
On many architectures, this function can perform better than is_power_of_two()
on the underlying integer type, as special handling of zero can be avoided.
Examples
Basic usage:
#![feature(nonzero_is_power_of_two)] let eight = std::num::NonZeroUsize::new(8).unwrap(); assert!(eight.is_power_of_two()); let ten = std::num::NonZeroUsize::new(10).unwrap(); assert!(!ten.is_power_of_two());Run
Trait Implementations
type Output = NonZeroUsize
type Output = NonZeroUsize
The resulting type after applying the | operator.
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, and cannot panic.
type Output = usize
type Output = usize
The resulting type after applying the / operator.
Converts NonZeroU16 to NonZeroUsize losslessly.
Converts a NonZeroUsize into an usize
This method tests for self and other values to be equal, and is used
by ==. Read more
This method tests for !=.
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 (for self and other) and is used by the > operator. Read more
This operation satisfies n % d == n - (n / d) * d, and cannot panic.
type Output = usize
type Output = usize
The resulting type after applying the % operator.
Attempts to convert NonZeroI128 to NonZeroUsize.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroI16 to NonZeroUsize.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroI32 to NonZeroUsize.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroI64 to NonZeroUsize.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroIsize to NonZeroUsize.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroU128 to NonZeroUsize.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroU32 to NonZeroUsize.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroU64 to NonZeroUsize.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroU8.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroU16.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroIsize.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroU32.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroU64.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroU128.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroI8.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroI16.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroI32.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroI64.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.
Attempts to convert NonZeroUsize to NonZeroI128.
type Error = TryFromIntError
type Error = TryFromIntError
The type returned in the event of a conversion error.