Struct rocket_governor::NonZeroU32

pub struct NonZeroU32(/* private fields */);

An integer that is known not to equal zero.

This enables some memory layout optimization. For example, Option<NonZeroU32> is the same size as u32:

use std::mem::size_of;
assert_eq!(size_of::<Option<core::num::NonZeroU32>>(), size_of::<u32>());

Layout

NonZeroU32 is guaranteed to have the same layout and bit validity as u32 with the exception that 0 is not a valid instance. Option<NonZeroU32> is guaranteed to be compatible with u32, including in FFI.

Thanks to the null pointer optimization, NonZeroU32 and Option<NonZeroU32> are guaranteed to have the same size and alignment:

use std::num::NonZeroU32;

assert_eq!(size_of::<NonZeroU32>(), size_of::<Option<NonZeroU32>>());
assert_eq!(align_of::<NonZeroU32>(), align_of::<Option<NonZeroU32>>());

Implementations

impl NonZeroU32

pub const unsafe fn new_unchecked(n: u32) -> NonZeroU32

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: u32) -> Option<NonZeroU32>

Creates a non-zero if the given value is not zero.

pub const fn get(self) -> u32

Returns the value as a primitive type.

impl NonZeroU32

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::NonZeroU32::new(u32::MAX).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::NonZeroU32::new(0b0101000).unwrap();

assert_eq!(n.trailing_zeros(), 3);

impl NonZeroU32

pub const fn checked_add(self, other: u32) -> Option<NonZeroU32>

Adds an unsigned integer to a non-zero value. Checks for overflow and returns None on overflow. As a consequence, the result cannot wrap to zero.

Examples

let one = NonZeroU32::new(1)?;
let two = NonZeroU32::new(2)?;
let max = NonZeroU32::new(u32::MAX)?;

assert_eq!(Some(two), one.checked_add(1));
assert_eq!(None, max.checked_add(1));

pub const fn saturating_add(self, other: u32) -> NonZeroU32

Adds an unsigned integer to a non-zero value. Return NonZeroU32::MAX on overflow.

Examples

let one = NonZeroU32::new(1)?;
let two = NonZeroU32::new(2)?;
let max = NonZeroU32::new(u32::MAX)?;

assert_eq!(two, one.saturating_add(1));
assert_eq!(max, max.saturating_add(1));

pub const unsafe fn unchecked_add(self, other: u32) -> NonZeroU32

🔬This is a nightly-only experimental API. (nonzero_ops)

Adds an unsigned integer to a non-zero value, 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 > u32::MAX.

Examples

#![feature(nonzero_ops)]

let one = NonZeroU32::new(1)?;
let two = NonZeroU32::new(2)?;

assert_eq!(two, unsafe { one.unchecked_add(1) });

pub const fn checked_next_power_of_two(self) -> Option<NonZeroU32>

Returns the smallest power of two greater than or equal to n. Checks for overflow and returns None if the next power of two is greater than the type’s maximum value. As a consequence, the result cannot wrap to zero.

Examples

let two = NonZeroU32::new(2)?;
let three = NonZeroU32::new(3)?;
let four = NonZeroU32::new(4)?;
let max = NonZeroU32::new(u32::MAX)?;

assert_eq!(Some(two), two.checked_next_power_of_two() );
assert_eq!(Some(four), three.checked_next_power_of_two() );
assert_eq!(None, max.checked_next_power_of_two() );

pub const fn ilog2(self) -> u32

Returns the base 2 logarithm of the number, rounded down.

This is the same operation as u32::ilog2, except that it has no failure cases to worry about since this value can never be zero.

Examples

assert_eq!(NonZeroU32::new(7).unwrap().ilog2(), 2);
assert_eq!(NonZeroU32::new(8).unwrap().ilog2(), 3);
assert_eq!(NonZeroU32::new(9).unwrap().ilog2(), 3);

pub const fn ilog10(self) -> u32

Returns the base 10 logarithm of the number, rounded down.

This is the same operation as u32::ilog10, except that it has no failure cases to worry about since this value can never be zero.

Examples

assert_eq!(NonZeroU32::new(99).unwrap().ilog10(), 1);
assert_eq!(NonZeroU32::new(100).unwrap().ilog10(), 2);
assert_eq!(NonZeroU32::new(101).unwrap().ilog10(), 2);

pub fn midpoint(self, rhs: NonZeroU32) -> NonZeroU32

🔬This is a nightly-only experimental API. (num_midpoint)

Calculates the middle point of self and rhs.

midpoint(a, b) is (a + b) >> 1 as if it were performed in a sufficiently-large signed integral type. This implies that the result is always rounded towards negative infinity and that no overflow will ever occur.

Examples

#![feature(num_midpoint)]

let one = NonZeroU32::new(1)?;
let two = NonZeroU32::new(2)?;
let four = NonZeroU32::new(4)?;

assert_eq!(one.midpoint(four), two);
assert_eq!(four.midpoint(one), two);

impl NonZeroU32

pub const fn checked_mul(self, other: NonZeroU32) -> Option<NonZeroU32>

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 = NonZeroU32::new(2)?;
let four = NonZeroU32::new(4)?;
let max = NonZeroU32::new(u32::MAX)?;

assert_eq!(Some(four), two.checked_mul(two));
assert_eq!(None, max.checked_mul(two));

pub const fn saturating_mul(self, other: NonZeroU32) -> NonZeroU32

Multiplies two non-zero integers together. Return NonZeroU32::MAX on overflow.

Examples

let two = NonZeroU32::new(2)?;
let four = NonZeroU32::new(4)?;
let max = NonZeroU32::new(u32::MAX)?;

assert_eq!(four, two.saturating_mul(two));
assert_eq!(max, four.saturating_mul(max));

pub const unsafe fn unchecked_mul(self, other: NonZeroU32) -> NonZeroU32

🔬This is a nightly-only experimental API. (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 > u32::MAX.

Examples

#![feature(nonzero_ops)]

let two = NonZeroU32::new(2)?;
let four = NonZeroU32::new(4)?;

assert_eq!(four, unsafe { two.unchecked_mul(two) });

pub const fn checked_pow(self, other: u32) -> Option<NonZeroU32>

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 = NonZeroU32::new(3)?;
let twenty_seven = NonZeroU32::new(27)?;
let half_max = NonZeroU32::new(u32::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) -> NonZeroU32

Raise non-zero value to an integer power. Return NonZeroU32::MAX on overflow.

Examples

let three = NonZeroU32::new(3)?;
let twenty_seven = NonZeroU32::new(27)?;
let max = NonZeroU32::new(u32::MAX)?;

assert_eq!(twenty_seven, three.saturating_pow(3));
assert_eq!(max, max.saturating_pow(3));

impl NonZeroU32

pub const fn is_power_of_two(self) -> bool

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:

let eight = std::num::NonZeroU32::new(8).unwrap();
assert!(eight.is_power_of_two());
let ten = std::num::NonZeroU32::new(10).unwrap();
assert!(!ten.is_power_of_two());

impl NonZeroU32

pub const MIN: NonZeroU32 = _

The smallest value that can be represented by this non-zero integer type, 1.

Examples

assert_eq!(NonZeroU32::MIN.get(), 1u32);

pub const MAX: NonZeroU32 = _

The largest value that can be represented by this non-zero integer type, equal to u32::MAX.

Examples

assert_eq!(NonZeroU32::MAX.get(), u32::MAX);

impl NonZeroU32

pub const BITS: u32 = 32u32

The size of this non-zero integer type in bits.

This value is equal to u32::BITS.

Examples

assert_eq!(NonZeroU32::BITS, u32::BITS);

Trait Implementations

impl Binary for NonZeroU32

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl BitOr<u32> for NonZeroU32

type Output = NonZeroU32

The resulting type after applying the | operator.

fn bitor(self, rhs: u32) -> <NonZeroU32 as BitOr<u32>>::Output

Performs the | operation.

impl BitOr for NonZeroU32

type Output = NonZeroU32

The resulting type after applying the | operator.

fn bitor(self, rhs: NonZeroU32) -> <NonZeroU32 as BitOr>::Output

Performs the | operation.

impl BitOrAssign<u32> for NonZeroU32

fn bitor_assign(&mut self, rhs: u32)

Performs the |= operation.

impl BitOrAssign for NonZeroU32

fn bitor_assign(&mut self, rhs: NonZeroU32)

Performs the |= operation.

impl CheckedBitPattern for NonZeroU32

type Bits = u32

Self must have the same layout as the specified Bits except for the possible invalid bit patterns being checked during is_valid_bit_pattern.

fn is_valid_bit_pattern(bits: &<NonZeroU32 as CheckedBitPattern>::Bits) -> bool

If this function returns true, then it must be valid to reinterpret bits as &Self.

impl Clone for NonZeroU32

fn clone(&self) -> NonZeroU32

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Contiguous for NonZeroU32

type Int = u32

The primitive integer type with an identical representation to this type.

const MAX_VALUE: u32 = 4_294_967_295u32

The upper inclusive bound for valid instances of this type.

const MIN_VALUE: u32 = 1u32

The lower inclusive bound for valid instances of this type.

fn from_integer(value: Self::Int) -> Option<Self>

If value is within the range for valid instances of this type, returns Some(converted_value), otherwise, returns None.

fn into_integer(self) -> Self::Int

Perform the conversion from C into the underlying integral type. This mostly exists otherwise generic code would need unsafe for the value as integer

impl Debug for NonZeroU32

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for NonZeroU32

fn deserialize<D>( deserializer: D ) -> Result<NonZeroU32, <D as Deserializer<'de>>::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for NonZeroU32

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl From<NonZeroU16> for NonZeroU32

fn from(small: NonZeroU16) -> NonZeroU32

Converts NonZeroU16 to NonZeroU32 losslessly.

impl From<NonZeroU8> for NonZeroU32

fn from(small: NonZeroU8) -> NonZeroU32

Converts NonZeroU8 to NonZeroU32 losslessly.

impl<'v> FromFormField<'v> for NonZeroU32

fn from_value(field: ValueField<'v>) -> Result<NonZeroU32, Errors<'v>>

Parse a value of T from a form value field.

fn from_data<'life0, 'async_trait>( field: DataField<'v, 'life0> ) -> Pin<Box<dyn Future<Output = Result<Self, Errors<'v>>> + Send + 'async_trait>>

where 'v: 'async_trait, 'life0: 'async_trait, Self: 'async_trait,

Parse a value of T from a form data field.

fn default() -> Option<Self>

Returns a default value, if any exists, to be used during lenient parsing when the form field is missing.

impl<'a> FromParam<'a> for NonZeroU32

type Error = &'a str

The associated error to be returned if parsing/validation fails.

fn from_param( param: &'a str ) -> Result<NonZeroU32, <NonZeroU32 as FromParam<'a>>::Error>

Parses and validates an instance of Self from a path parameter string or returns an Error if parsing or validation fails.

impl FromStr for NonZeroU32

type Err = ParseIntError

The associated error which can be returned from parsing.

fn from_str(src: &str) -> Result<NonZeroU32, <NonZeroU32 as FromStr>::Err>

Parses a string s to return a value of this type.

impl<'x, P> FromUriParam<P, &'x NonZeroU32> for NonZeroU32

where P: Part,

type Target = &'x NonZeroU32

The resulting type of this conversion.

fn from_uri_param(param: &'x NonZeroU32) -> &'x NonZeroU32

Converts a value of type T into a value of type Self::Target. The resulting value of type Self::Target will be rendered into a URI using its [UriDisplay] implementation.

impl<'x, P> FromUriParam<P, &'x mut NonZeroU32> for NonZeroU32

where P: Part,

type Target = &'x mut NonZeroU32

The resulting type of this conversion.

fn from_uri_param(param: &'x mut NonZeroU32) -> &'x mut NonZeroU32

Converts a value of type T into a value of type Self::Target. The resulting value of type Self::Target will be rendered into a URI using its [UriDisplay] implementation.

impl<P> FromUriParam<P, NonZeroU32> for NonZeroU32

where P: Part,

type Target = NonZeroU32

The resulting type of this conversion.

fn from_uri_param(param: NonZeroU32) -> NonZeroU32

Converts a value of type T into a value of type Self::Target. The resulting value of type Self::Target will be rendered into a URI using its [UriDisplay] implementation.

impl Hash for NonZeroU32

fn hash<__H>(&self, state: &mut __H)

where __H: Hasher,

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl LowerHex for NonZeroU32

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl NonZero for NonZeroU32

type Primitive = u32

The primitive type (e.g. u8) underlying this integral type.

fn new(n: u32) -> Option<NonZeroU32>

Creates a new non-zero object from an integer that might be zero.

fn get(self) -> <NonZeroU32 as NonZero>::Primitive

Returns the value as a primitive type.

impl Octal for NonZeroU32

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Ord for NonZeroU32

fn cmp(&self, other: &NonZeroU32) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for NonZeroU32

fn eq(&self, other: &NonZeroU32) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for NonZeroU32

fn partial_cmp(&self, other: &NonZeroU32) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for NonZeroU32

fn serialize<S>( &self, serializer: S ) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl TryFrom<NonZeroI128> for NonZeroU32

fn try_from( value: NonZeroI128 ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroI128>>::Error>

Attempts to convert NonZeroI128 to NonZeroU32.

type Error = TryFromIntError

The type returned in the event of a conversion error.

impl TryFrom<NonZeroI16> for NonZeroU32

fn try_from( value: NonZeroI16 ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroI16>>::Error>

Attempts to convert NonZeroI16 to NonZeroU32.

type Error = TryFromIntError

The type returned in the event of a conversion error.

impl TryFrom<NonZeroI32> for NonZeroU32

fn try_from( value: NonZeroI32 ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroI32>>::Error>

Attempts to convert NonZeroI32 to NonZeroU32.

type Error = TryFromIntError

The type returned in the event of a conversion error.

impl TryFrom<NonZeroI64> for NonZeroU32

fn try_from( value: NonZeroI64 ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroI64>>::Error>

Attempts to convert NonZeroI64 to NonZeroU32.

type Error = TryFromIntError

The type returned in the event of a conversion error.

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

The type returned in the event of a conversion error.

impl TryFrom<NonZeroIsize> for NonZeroU32

fn try_from( value: NonZeroIsize ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroIsize>>::Error>

Attempts to convert NonZeroIsize to NonZeroU32.

type Error = TryFromIntError

The type returned in the event of a conversion error.

impl TryFrom<NonZeroU128> for NonZeroU32

fn try_from( value: NonZeroU128 ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroU128>>::Error>

Attempts to convert NonZeroU128 to NonZeroU32.

type Error = TryFromIntError

The type returned in the event of a conversion error.

impl TryFrom<NonZeroU64> for NonZeroU32

fn try_from( value: NonZeroU64 ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroU64>>::Error>

Attempts to convert NonZeroU64 to NonZeroU32.

type Error = TryFromIntError

The type returned in the event of a conversion error.

impl TryFrom<NonZeroUsize> for NonZeroU32

fn try_from( value: NonZeroUsize ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<NonZeroUsize>>::Error>

Attempts to convert NonZeroUsize to NonZeroU32.

type Error = TryFromIntError

The type returned in the event of a conversion error.

impl TryFrom<u32> for NonZeroU32

fn try_from( value: u32 ) -> Result<NonZeroU32, <NonZeroU32 as TryFrom<u32>>::Error>

Attempts to convert u32 to NonZeroU32.

type Error = TryFromIntError

The type returned in the event of a conversion error.

impl UpperHex for NonZeroU32

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl<P> UriDisplay<P> for NonZeroU32

where P: Part,

This implementation is identical to the Display implementation.

fn fmt(&self, f: &mut Formatter<'_, P>) -> Result<(), Error>

Formats self in a URI-safe manner using the given formatter.

impl Value for NonZeroU32

fn record(&self, key: &Field, visitor: &mut dyn Visit)

Visits this value with the given Visitor.

impl Copy for NonZeroU32

impl Eq for NonZeroU32

impl NoUninit for NonZeroU32

impl PodInOption for NonZeroU32

impl StructuralEq for NonZeroU32

impl StructuralPartialEq for NonZeroU32

impl ZeroableInOption for NonZeroU32