Struct pow2::Pow2

#[repr(transparent)]
pub struct Pow2(_);

Represents a non-negative power of 2, by storing its exponent.

This type is limited in range to 2^0 .. 2^255 (inclusive). It is simply a wrapper around a u8, which stores the exponent.

See module docs for more info.

Implementations

impl Pow2

pub const fn from_exponent(exponent: u8) -> Pow2

Creates a Pow2 from an exponent. Note that this function does not check whether the given exponent is valid for any specific primitive type; many values will be useless. For example, using Pow2::from_exponent(250) will not be useful for any current primitive type.

pub const fn exponent(self) -> u8

Returns the exponent of the Pow2.

pub const fn align_of<T>() -> Pow2

Returns a Pow2 value for the memory alignment of a given type T.

use pow2::Pow2;
assert_eq!(Pow2::align_of::<u32>(), Pow2::from_exponent(2));
assert_eq!(Pow2::align_of::<u64>(), Pow2::from_exponent(3));

pub fn checked_mul(self, other: Pow2) -> Option<Pow2>

Multiplies two Pow2 values by adding their exponents. If the values are out of range, returns None.

use pow2::Pow2;
assert_eq!(Pow2::from_exponent(2).checked_mul(Pow2::from_exponent(3)), Some(Pow2::from_exponent(5)));
assert_eq!(Pow2::from_exponent(200).checked_mul(Pow2::from_exponent(200)), None);

pub fn checked_div(self, other: Pow2) -> Option<Pow2>

Divides a Pow2 value by another Pow2. If the divisor is greater than the quotient, then returns None.

use pow2::Pow2;
assert_eq!(Pow2::from_exponent(4).checked_div(Pow2::from_exponent(1)), Some(Pow2::from_exponent(3)));
assert_eq!(Pow2::from_exponent(4).checked_div(Pow2::from_exponent(8)), None);

pub const fn mul(self, other: Pow2) -> Pow2

Multiplies two Pow2 values by adding their exponents. If the values are out of range, then normal arithmetic overflow handling occurs.

use pow2::Pow2;
assert_eq!(Pow2::from_exponent(4) * Pow2::from_exponent(3), Pow2::from_exponent(7));

pub const fn div(self, other: Pow2) -> Pow2

Divides a Pow2 value by another Pow2. If the divisor is greater than the quotient, then normal arithmetic overflow handling occurs.

use pow2::Pow2;
assert_eq!(Pow2::from_exponent(12) / Pow2::from_exponent(2), Pow2::from_exponent(10));

pub fn is_aligned<T: IntPow2>(self, n: T) -> bool

Returns true if n is an integer multiple of self (is aligned).

use pow2::Pow2;
const PAGE_SIZE: Pow2 = Pow2::from_exponent(12);
assert_eq!(PAGE_SIZE.is_aligned(0u32), true);
assert_eq!(PAGE_SIZE.is_aligned(1000u32), false);
assert_eq!(PAGE_SIZE.is_aligned(4095u32), false);
assert_eq!(PAGE_SIZE.is_aligned(4096u32), true);
assert_eq!(PAGE_SIZE.is_aligned(4097u32), false);
assert_eq!(PAGE_SIZE.is_aligned(8192u32), true);
assert_eq!(PAGE_SIZE.is_aligned(core::u32::MAX), false);

pub fn align_up<T: IntPow2>(self, n: T) -> Option<T>

Returns the smallest multiple of self (a power of 2) that is greater than or equal to n.

If the aligned value would overflow the range of T, then this function returns None.

use pow2::Pow2;
const PAGE_SIZE: Pow2 = Pow2::from_exponent(12);
assert_eq!(PAGE_SIZE.align_up(5000u32), Some(8192));
assert_eq!(PAGE_SIZE.align_up(core::u32::MAX), None); // would overflow

pub fn align_up_unchecked<T: IntPow2>(self, n: T) -> T

Returns the smallest multiple of self (a power of 2) that is greater than or equal to n.

If the aligned value would overflow the range of T, then normal arithmetic overflow handling occurs.

use pow2::Pow2;

pub fn align_down<T: IntPow2>(self, n: T) -> T

Returns the largest multiple of self (a power of 2) that is less than or equal to n.

Trait Implementations

impl Clone for Pow2

fn clone(&self) -> Pow2

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Pow2

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

Formats the value using the given formatter.

impl Div<Pow2> for Pow2

type Output = Pow2

The resulting type after applying the / operator.

fn div(self, other: Pow2) -> Pow2

Performs the / operation.

impl Div<Pow2> for i128

type Output = i128

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for i16

type Output = i16

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for i32

type Output = i32

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for i64

type Output = i64

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for i8

type Output = i8

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for isize

type Output = isize

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for u128

type Output = u128

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for u16

type Output = u16

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for u32

type Output = u32

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for u64

type Output = u64

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for u8

type Output = u8

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl Div<Pow2> for usize

type Output = usize

The resulting type after applying the / operator.

fn div(self, rhs: Pow2) -> Self

Performs the / operation.

impl From<Pow2> for i128

fn from(p: Pow2) -> i128

Converts to this type from the input type.

impl From<Pow2> for i16

fn from(p: Pow2) -> i16

Converts to this type from the input type.

impl From<Pow2> for i32

fn from(p: Pow2) -> i32

Converts to this type from the input type.

impl From<Pow2> for i64

fn from(p: Pow2) -> i64

Converts to this type from the input type.

impl From<Pow2> for i8

fn from(p: Pow2) -> i8

Converts to this type from the input type.

impl From<Pow2> for isize

fn from(p: Pow2) -> isize

Converts to this type from the input type.

impl From<Pow2> for u128

fn from(p: Pow2) -> u128

Converts to this type from the input type.

impl From<Pow2> for u16

fn from(p: Pow2) -> u16

Converts to this type from the input type.

impl From<Pow2> for u32

fn from(p: Pow2) -> u32

Converts to this type from the input type.

impl From<Pow2> for u64

fn from(p: Pow2) -> u64

Converts to this type from the input type.

impl From<Pow2> for u8

fn from(p: Pow2) -> u8

Converts to this type from the input type.

impl From<Pow2> for usize

fn from(p: Pow2) -> usize

Converts to this type from the input type.

impl Hash for Pow2

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

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 Mul<Pow2> for Pow2

type Output = Pow2

The resulting type after applying the * operator.

fn mul(self, other: Pow2) -> Pow2

Performs the * operation.

impl Mul<Pow2> for i128

type Output = i128

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for i16

type Output = i16

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for i32

type Output = i32

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for i64

type Output = i64

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for i8

type Output = i8

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for isize

type Output = isize

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for u128

type Output = u128

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for u16

type Output = u16

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for u32

type Output = u32

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for u64

type Output = u64

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for u8

type Output = u8

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Mul<Pow2> for usize

type Output = usize

The resulting type after applying the * operator.

fn mul(self, rhs: Pow2) -> Self

Performs the * operation.

impl Ord for Pow2

fn cmp(&self, other: &Pow2) -> Ordering

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl PartialEq<Pow2> for Pow2

fn eq(&self, other: &Pow2) -> 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<Pow2> for Pow2

fn partial_cmp(&self, other: &Pow2) -> 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 TryFrom<i128> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: i128) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<i16> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: i16) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<i32> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: i32) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<i64> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: i64) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<i8> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: i8) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<isize> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: isize) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<u128> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: u128) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<u16> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: u16) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<u32> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: u32) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<u64> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: u64) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<u8> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: u8) -> Result<Pow2, NotPow2>

Performs the conversion.

impl TryFrom<usize> for Pow2

type Error = NotPow2

The type returned in the event of a conversion error.

fn try_from(n: usize) -> Result<Pow2, NotPow2>

Performs the conversion.

impl Copy for Pow2

impl Eq for Pow2

impl StructuralEq for Pow2

impl StructuralPartialEq for Pow2