Struct ethnum::I256

source ·

#[repr(transparent)]
pub struct I256(pub [i128; 2]);

Expand description

A 256-bit signed integer type.

Tuple Fields§

§0: [i128; 2]

Implementations§

source §

impl I256

source

pub const MIN: Self = _

The smallest value that can be represented by this integer type, -2²⁵⁵.

pub const MAX: Self = _

The largest value that can be represented by this integer type, 2²⁵⁵ - 1.

pub const BITS: u32 = 256u32

The size of this integer type in bits.

pub fn from_str_radix(src: &str, radix: u32) -> Result<Self, ParseIntError>

Converts a string slice in a given base to an integer.

The string is expected to be an optional + or - 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.

pub const fn count_ones(self) -> u32

Returns the number of ones in the binary representation of self.

pub const fn count_zeros(self) -> u32

Returns the number of zeros in the binary representation of self.

pub fn leading_zeros(self) -> u32

Returns the number of leading zeros in the binary representation of self.

pub fn trailing_zeros(self) -> u32

Returns the number of trailing zeros in the binary representation of self.

pub fn leading_ones(self) -> u32

Returns the number of leading ones in the binary representation of self.

pub fn trailing_ones(self) -> u32

Returns the number of trailing ones in the binary representation of self.

pub fn rotate_left(self, n: u32) -> Self

Shifts the bits to the left by a specified amount, n, wrapping the truncated bits to the end of the resulting integer.

Please note this isn’t the same operation as the << shifting operator!

pub fn rotate_right(self, n: u32) -> Self

Shifts 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!

pub const fn swap_bytes(self) -> Self

Reverses the byte order of the integer.

pub const fn reverse_bits(self) -> Self

Reverses 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.

pub const fn from_be(x: Self) -> Self

Converts an integer from big endian to the target’s endianness.

On big endian this is a no-op. On little endian the bytes are swapped.

pub const fn from_le(x: Self) -> Self

Converts 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.

pub const fn to_be(self) -> Self

Converts self to big endian from the target’s endianness.

On big endian this is a no-op. On little endian the bytes are swapped.

pub const fn to_le(self) -> Self

Converts self to little endian from the target’s endianness.

On little endian this is a no-op. On big endian the bytes are swapped.

pub fn checked_add(self, rhs: Self) -> Option<Self>

Checked integer addition. Computes self + rhs, returning None if overflow occurred.

pub fn checked_add_unsigned(self, rhs: U256) -> Option<Self>

Checked addition with an unsigned integer. Computes self + rhs, returning None if overflow occurred.

pub fn checked_sub(self, rhs: Self) -> Option<Self>

Checked integer subtraction. Computes self - rhs, returning None if overflow occurred.

pub fn checked_sub_unsigned(self, rhs: U256) -> Option<Self>

Checked subtraction with an unsigned integer. Computes self - rhs, returning None if overflow occurred.

pub fn checked_mul(self, rhs: Self) -> Option<Self>

Checked integer multiplication. Computes self * rhs, returning None if overflow occurred.

pub fn checked_div(self, rhs: Self) -> Option<Self>

Checked integer division. Computes self / rhs, returning None if rhs == 0 or the division results in overflow.

pub fn checked_div_euclid(self, rhs: Self) -> Option<Self>

Checked Euclidean division. Computes self.div_euclid(rhs), returning None if rhs == 0 or the division results in overflow.

pub fn checked_rem(self, rhs: Self) -> Option<Self>

Checked integer remainder. Computes self % rhs, returning None if rhs == 0 or the division results in overflow.

pub fn checked_rem_euclid(self, rhs: Self) -> Option<Self>

Checked Euclidean remainder. Computes self.rem_euclid(rhs), returning None if rhs == 0 or the division results in overflow.

pub fn checked_neg(self) -> Option<Self>

Checked negation. Computes -self, returning None if self == MIN.

pub fn checked_shl(self, rhs: u32) -> Option<Self>

Checked shift left. Computes self << rhs, returning None if rhs is larger than or equal to the number of bits in self.

pub fn checked_shr(self, rhs: u32) -> Option<Self>

Checked shift right. Computes self >> rhs, returning None if rhs is larger than or equal to the number of bits in self.

pub fn checked_abs(self) -> Option<Self>

Checked absolute value. Computes self.abs(), returning None if self == MIN.

pub fn checked_pow(self, exp: u32) -> Option<Self>

Checked exponentiation. Computes self.pow(exp), returning None if overflow occurred.

pub fn saturating_add(self, rhs: Self) -> Self

Saturating integer addition. Computes self + rhs, saturating at the numeric bounds instead of overflowing.

pub fn saturating_add_unsigned(self, rhs: U256) -> Self

Saturating addition with an unsigned integer. Computes self + rhs, saturating at the numeric bounds instead of overflowing.

pub fn saturating_sub(self, rhs: Self) -> Self

Saturating integer subtraction. Computes self - rhs, saturating at the numeric bounds instead of overflowing.

pub fn saturating_sub_unsigned(self, rhs: U256) -> Self

Saturating subtraction with an unsigned integer. Computes self - rhs, saturating at the numeric bounds instead of overflowing.

pub fn saturating_neg(self) -> Self

Saturating integer negation. Computes -self, returning MAX if self == MIN instead of overflowing.

pub fn saturating_abs(self) -> Self

Saturating absolute value. Computes self.abs(), returning MAX if self == MIN instead of overflowing.

pub fn saturating_mul(self, rhs: Self) -> Self

Saturating integer multiplication. Computes self * rhs, saturating at the numeric bounds instead of overflowing.

pub fn saturating_div(self, rhs: Self) -> Self

Saturating integer division. Computes self / rhs, saturating at the numeric bounds instead of overflowing.

pub fn saturating_pow(self, exp: u32) -> Self

Saturating integer exponentiation. Computes self.pow(exp), saturating at the numeric bounds instead of overflowing.

pub fn wrapping_add(self, rhs: Self) -> Self

Wrapping (modular) addition. Computes self + rhs, wrapping around at the boundary of the type.

pub fn wrapping_add_unsigned(self, rhs: U256) -> Self

Wrapping (modular) addition with an unsigned integer. Computes self + rhs, wrapping around at the boundary of the type.

pub fn wrapping_sub(self, rhs: Self) -> Self

Wrapping (modular) subtraction. Computes self - rhs, wrapping around at the boundary of the type.

pub fn wrapping_sub_unsigned(self, rhs: U256) -> Self

Wrapping (modular) subtraction with an unsigned integer. Computes self - rhs, wrapping around at the boundary of the type.

pub fn wrapping_mul(self, rhs: Self) -> Self

Wrapping (modular) multiplication. Computes self * rhs, wrapping around at the boundary of the type.

pub fn wrapping_div(self, rhs: Self) -> Self

Wrapping (modular) division. Computes self / rhs, wrapping around at the boundary of the type.

The only case where such wrapping can occur is when one divides MIN / -1 on a signed type (where MIN is the negative minimal value for the type); this is equivalent to -MIN, a positive value that is too large to represent in the type. In such a case, this function returns MIN itself.

Panics

This function will panic if rhs is 0.

Examples

Basic usage:

assert_eq!(I256::new(100).wrapping_div(I256::new(10)), 10);
assert_eq!(I256::MIN.wrapping_div(I256::new(-1)), I256::MIN);

source

pub fn wrapping_div_euclid(self, rhs: Self) -> Self

Wrapping Euclidean division. Computes self.div_euclid(rhs), wrapping around at the boundary of the type.

Wrapping will only occur in MIN / -1 on a signed type (where MIN is the negative minimal value for the type). This is equivalent to -MIN, a positive value that is too large to represent in the type. In this case, this method returns MIN itself.

Panics

This function will panic if rhs is 0.

Examples

Basic usage:

assert_eq!(I256::new(100).wrapping_div_euclid(I256::new(10)), 10);
assert_eq!(I256::MIN.wrapping_div_euclid(I256::new(-1)), I256::MIN);

source

pub fn wrapping_rem(self, rhs: Self) -> Self

Wrapping (modular) remainder. Computes self % rhs, wrapping around at the boundary of the type.

Such wrap-around never actually occurs mathematically; implementation artifacts make x % y invalid for MIN / -1 on a signed type (where MINis the negative minimal value). In such a case, this function returns0`.

Panics

This function will panic if rhs is 0.

Examples

Basic usage:

assert_eq!(I256::new(100).wrapping_rem(I256::new(10)), 0);
assert_eq!(I256::MIN.wrapping_rem(I256::new(-1)), 0);

source

pub fn wrapping_rem_euclid(self, rhs: Self) -> Self

Wrapping Euclidean remainder. Computes self.rem_euclid(rhs), wrapping around at the boundary of the type.

Wrapping will only occur in MIN % -1 on a signed type (where MIN is the negative minimal value for the type). In this case, this method returns 0.

Panics

This function will panic if rhs is 0.

Examples

Basic usage:

assert_eq!(I256::new(100).wrapping_rem_euclid(I256::new(10)), 0);
assert_eq!(I256::MIN.wrapping_rem_euclid(I256::new(-1)), 0);

source

pub fn wrapping_neg(self) -> Self

Wrapping (modular) negation. Computes -self, wrapping around at the boundary of the type.

The only case where such wrapping can occur is when one negates MIN on a signed type (where MIN is the negative minimal value for the type); this is a positive value that is too large to represent in the type. In such a case, this function returns MIN itself.

Examples

Basic usage:

assert_eq!(I256::new(100).wrapping_neg(), -100);
assert_eq!(I256::MIN.wrapping_neg(), I256::MIN);

source

pub fn wrapping_shl(self, rhs: u32) -> Self

Panic-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!(I256::new(-1).wrapping_shl(7), -128);
assert_eq!(I256::new(-1).wrapping_shl(128), I256::from_words(-1, 0));
assert_eq!(I256::new(-1).wrapping_shl(256), -1);

source

pub fn wrapping_shr(self, rhs: u32) -> Self

Panic-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!(I256::new(-128).wrapping_shr(7), -1);
assert_eq!((-128i16).wrapping_shr(64), -128);

source

pub fn wrapping_abs(self) -> Self

Wrapping (modular) absolute value. Computes self.abs(), wrapping around at the boundary of the type.

The only case where such wrapping can occur is when one takes the absolute value of the negative minimal value for the type; this is a positive value that is too large to represent in the type. In such a case, this function returns MIN itself.

Examples

Basic usage:

assert_eq!(I256::new(100).wrapping_abs(), 100);
assert_eq!(I256::new(-100).wrapping_abs(), 100);
assert_eq!(I256::MIN.wrapping_abs(), I256::MIN);
assert_eq!(
    I256::MIN.wrapping_abs().as_u256(),
    U256::from_words(
        0x80000000000000000000000000000000,
        0x00000000000000000000000000000000,
    ),
);

source

pub fn unsigned_abs(self) -> U256

Computes the absolute value of self without any wrapping or panicking.

Examples

Basic usage:

assert_eq!(I256::new(100).unsigned_abs(), 100);
assert_eq!(I256::new(-100).unsigned_abs(), 100);
assert_eq!(
    I256::MIN.unsigned_abs(),
    U256::from_words(
        0x80000000000000000000000000000000,
        0x00000000000000000000000000000000,
    ),
);

source

pub fn wrapping_pow(self, exp: u32) -> Self

Wrapping (modular) exponentiation. Computes self.pow(exp), wrapping around at the boundary of the type.

Examples

Basic usage:

assert_eq!(I256::new(3).wrapping_pow(4), 81);
assert_eq!(3i8.wrapping_pow(5), -13);
assert_eq!(3i8.wrapping_pow(6), -39);

source

pub fn overflowing_add(self, rhs: Self) -> (Self, bool)

Calculates 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!(I256::new(5).overflowing_add(I256::new(2)), (I256::new(7), false));
assert_eq!(I256::MAX.overflowing_add(I256::new(1)), (I256::MIN, true));

source

pub fn overflowing_add_unsigned(self, rhs: U256) -> (Self, bool)

Calculates self + rhs with an unsigned 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!(I256::new(1).overflowing_add_unsigned(U256::new(2)), (I256::new(3), false));
assert_eq!((I256::MIN).overflowing_add_unsigned(U256::MAX), (I256::MAX, false));
assert_eq!((I256::MAX - 2).overflowing_add_unsigned(U256::new(3)), (I256::MIN, true));

source

pub fn overflowing_sub(self, rhs: Self) -> (Self, bool)

Calculates 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!(I256::new(5).overflowing_sub(I256::new(2)), (I256::new(3), false));
assert_eq!(I256::MIN.overflowing_sub(I256::new(1)), (I256::MAX, true));

source

pub fn overflowing_sub_unsigned(self, rhs: U256) -> (Self, bool)

Calculates self - rhs with an unsigned 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!(I256::new(1).overflowing_sub_unsigned(U256::new(2)), (I256::new(-1), false));
assert_eq!((I256::MAX).overflowing_sub_unsigned(U256::MAX), (I256::MIN, false));
assert_eq!((I256::MIN + 2).overflowing_sub_unsigned(U256::new(3)), (I256::MAX, true));

source

pub fn abs_diff(self, other: Self) -> U256

Computes the absolute difference between self and other.

This function always returns the correct answer without overflow or panics by returning an unsigned integer.

Examples

Basic usage:

assert_eq!(I256::new(100).abs_diff(I256::new(80)), 20);
assert_eq!(I256::new(100).abs_diff(I256::new(110)), 10);
assert_eq!(I256::new(-100).abs_diff(I256::new(80)), 180);
assert_eq!(I256::new(-100).abs_diff(I256::new(-120)), 20);
assert_eq!(I256::MIN.abs_diff(I256::MAX), U256::MAX);
assert_eq!(I256::MAX.abs_diff(I256::MIN), U256::MAX);

source

pub fn overflowing_mul(self, rhs: Self) -> (Self, bool)

Calculates 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:

assert_eq!(I256::new(5).overflowing_mul(I256::new(2)), (I256::new(10), false));
assert_eq!(I256::MAX.overflowing_mul(I256::new(2)), (I256::new(-2), true));

source

pub fn overflowing_div(self, rhs: Self) -> (Self, bool)

Calculates 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. If an overflow would occur then self is returned.

Panics

This function will panic if rhs is 0.

Examples

Basic usage:

assert_eq!(I256::new(5).overflowing_div(I256::new(2)), (I256::new(2), false));
assert_eq!(I256::MIN.overflowing_div(I256::new(-1)), (I256::MIN, true));

source

pub fn overflowing_div_euclid(self, rhs: Self) -> (Self, bool)

Calculates 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. If an overflow would occur then self is returned.

Panics

This function will panic if rhs is 0.

Examples

Basic usage:

assert_eq!(I256::new(5).overflowing_div_euclid(I256::new(2)), (I256::new(2), false));
assert_eq!(I256::MIN.overflowing_div_euclid(I256::new(-1)), (I256::MIN, true));

source

pub fn overflowing_rem(self, rhs: Self) -> (Self, bool)

Calculates 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. If an overflow would occur then 0 is returned.

Panics

This function will panic if rhs is 0.

Examples

Basic usage:

assert_eq!(I256::new(5).overflowing_rem(I256::new(2)), (I256::new(1), false));
assert_eq!(I256::MIN.overflowing_rem(I256::new(-1)), (I256::new(0), true));

source

pub fn overflowing_rem_euclid(self, rhs: Self) -> (Self, bool)

Overflowing Euclidean remainder. Calculates self.rem_euclid(rhs).

Returns a tuple of the remainder after dividing along with a boolean indicating whether an arithmetic overflow would occur. If an overflow would occur then 0 is returned.

Panics

This function will panic if rhs is 0.

Examples

Basic usage:

assert_eq!(I256::new(5).overflowing_rem_euclid(I256::new(2)), (I256::new(1), false));
assert_eq!(I256::MIN.overflowing_rem_euclid(I256::new(-1)), (I256::new(0), true));

source

pub fn overflowing_neg(self) -> (Self, bool)

Negates self, overflowing if this is equal to the minimum value.

Returns a tuple of the negated version of self along with a boolean indicating whether an overflow happened. If self is the minimum value (e.g., i32::MIN for values of type i32), then the minimum value will be returned again and true will be returned for an overflow happening.

Examples

Basic usage:

assert_eq!(I256::new(2).overflowing_neg(), (I256::new(-2), false));
assert_eq!(I256::MIN.overflowing_neg(), (I256::MIN, true));

source

pub fn overflowing_shl(self, rhs: u32) -> (Self, bool)

Shifts 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!(I256::new(1).overflowing_shl(4), (I256::new(0x10), false));
assert_eq!(I256::new(1).overflowing_shl(260), (I256::new(0x10), true));

source

pub fn overflowing_shr(self, rhs: u32) -> (Self, bool)

Shifts 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!(I256::new(0x10).overflowing_shr(4), (I256::new(0x1), false));
assert_eq!(I256::new(0x10).overflowing_shr(260), (I256::new(0x1), true));

source

pub fn overflowing_abs(self) -> (Self, bool)

Computes the absolute value of self.

Returns a tuple of the absolute version of self along with a boolean indicating whether an overflow happened. If self is the minimum value (e.g., I256::MIN for values of type I256), then the minimum value will be returned again and true will be returned for an overflow happening.

Examples

Basic usage:

assert_eq!(I256::new(10).overflowing_abs(), (I256::new(10), false));
assert_eq!(I256::new(-10).overflowing_abs(), (I256::new(10), false));
assert_eq!(I256::MIN.overflowing_abs(), (I256::MIN, true));

source

pub fn overflowing_pow(self, exp: u32) -> (Self, bool)

Raises self to the power of exp, using exponentiation by squaring.

Returns a tuple of the exponentiation along with a bool indicating whether an overflow happened.

Examples

Basic usage:

assert_eq!(I256::new(3).overflowing_pow(4), (I256::new(81), false));
assert_eq!(
    I256::new(10).overflowing_pow(77),
    (
        I256::from_words(
            -46408779215366586471190473126206792002,
            -113521875028918879454725857041952276480,
        ),
        true,
    )
);

source

pub fn pow(self, exp: u32) -> Self

Raises self to the power of exp, using exponentiation by squaring.

Examples

Basic usage:


assert_eq!(I256::new(2).pow(5), 32);

source

pub fn div_euclid(self, rhs: Self) -> Self

Calculates the quotient of Euclidean division of self by rhs.

This computes the integer q such that self = q * rhs + r, with r = self.rem_euclid(rhs) and 0 <= r < abs(rhs).

In other words, the result is self / rhs rounded to the integer q such that self >= q * rhs. If self > 0, this is equal to round towards zero (the default in Rust); if self < 0, this is equal to round towards +/- infinity.

Panics

This function will panic if rhs is 0 or the division results in overflow.

Examples

Basic usage:

let a = I256::new(7);
let b = I256::new(4);

assert_eq!(a.div_euclid(b), 1); // 7 >= 4 * 1
assert_eq!(a.div_euclid(-b), -1); // 7 >= -4 * -1
assert_eq!((-a).div_euclid(b), -2); // -7 >= 4 * -2
assert_eq!((-a).div_euclid(-b), 2); // -7 >= -4 * 2

source

pub fn rem_euclid(self, rhs: Self) -> Self

Calculates the least nonnegative remainder of self (mod rhs).

This is done as if by the Euclidean division algorithm – given r = self.rem_euclid(rhs), self = rhs * self.div_euclid(rhs) + r, and 0 <= r < abs(rhs).

Panics

This function will panic if rhs is 0 or the division results in overflow.

Examples

Basic usage:

let a = I256::new(7);
let b = I256::new(4);

assert_eq!(a.rem_euclid(b), 3);
assert_eq!((-a).rem_euclid(b), 1);
assert_eq!(a.rem_euclid(-b), 3);
assert_eq!((-a).rem_euclid(-b), 1);

source

pub fn abs(self) -> Self

Computes the absolute value of self.

Overflow behavior

The absolute value of I256::MIN cannot be represented as an I256, and attempting to calculate it will cause an overflow. This means that code in debug mode will trigger a panic on this case and optimized code will return I256::MIN without a panic.

Examples

Basic usage:

assert_eq!(I256::new(10).abs(), 10);
assert_eq!(I256::new(-10).abs(), 10);

source

pub const fn signum(self) -> Self

Returns a number representing sign of self.

0 if the number is zero
1 if the number is positive
-1 if the number is negative

Examples

Basic usage:

assert_eq!(I256::new(10).signum(), 1);
assert_eq!(I256::new(0).signum(), 0);
assert_eq!(I256::new(-10).signum(), -1);

source

pub const fn signum128(self) -> i128

Returns a number representing sign of self as a 64-bit signed integer.

0 if the number is zero
1 if the number is positive
-1 if the number is negative

Examples

Basic usage:

assert_eq!(I256::new(10).signum128(), 1i128);
assert_eq!(I256::new(0).signum128(), 0i128);
assert_eq!(I256::new(-10).signum128(), -1i128);

source

pub const fn is_positive(self) -> bool

Returns true if self is positive and false if the number is zero or negative.

Examples

Basic usage:

assert!(I256::new(10).is_positive());
assert!(!I256::new(-10).is_positive());

source

pub const fn is_negative(self) -> bool

Returns true if self is negative and false if the number is zero or positive.

Examples

Basic usage:

assert!(I256::new(-10).is_negative());
assert!(!I256::new(10).is_negative());

source

pub const fn to_be_bytes(self) -> [u8; 32]

Return the memory representation of this integer as a byte array in big-endian (network) byte order.

Examples

let bytes = I256::from_words(
    0x00010203_04050607_08090a0b_0c0d0e0f,
    0x10111213_14151617_18191a1b_1c1d1e1f,
);
assert_eq!(
    bytes.to_be_bytes(),
    [
        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
    ],
);

source

pub const fn to_le_bytes(self) -> [u8; 32]

Return the memory representation of this integer as a byte array in little-endian byte order.

Examples

let bytes = I256::from_words(
    0x00010203_04050607_08090a0b_0c0d0e0f,
    0x10111213_14151617_18191a1b_1c1d1e1f,
);
assert_eq!(
    bytes.to_le_bytes(),
    [
        0x1f, 0x1e, 0x1d, 0x1c, 0x1b, 0x1a, 0x19, 0x18, 0x17, 0x16, 0x15, 0x14, 0x13, 0x12, 0x11, 0x10,
        0x0f, 0x0e, 0x0d, 0x0c, 0x0b, 0x0a, 0x09, 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01, 0x00,
    ],
);

source

pub const fn to_ne_bytes(self) -> [u8; 32]

Return 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 = I256::from_words(
    0x00010203_04050607_08090a0b_0c0d0e0f,
    0x10111213_14151617_18191a1b_1c1d1e1f,
);
assert_eq!(
    bytes.to_ne_bytes(),
    if cfg!(target_endian = "big") {
        [
            0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
            0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
        ]
    } else {
        [
            0x1f, 0x1e, 0x1d, 0x1c, 0x1b, 0x1a, 0x19, 0x18, 0x17, 0x16, 0x15, 0x14, 0x13, 0x12, 0x11, 0x10,
            0x0f, 0x0e, 0x0d, 0x0c, 0x0b, 0x0a, 0x09, 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01, 0x00,
        ]
    }
);

source

pub const fn from_be_bytes(bytes: [u8; 32]) -> Self

Create an integer value from its representation as a byte array in big endian.

Examples

let value = I256::from_be_bytes([
    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
]);
assert_eq!(
    value,
    I256::from_words(
        0x00010203_04050607_08090a0b_0c0d0e0f,
        0x10111213_14151617_18191a1b_1c1d1e1f,
    ),
);

When starting from a slice rather than an array, fallible conversion APIs can be used:

fn read_be_i256(input: &mut &[u8]) -> I256 {
    let (int_bytes, rest) = input.split_at(std::mem::size_of::<I256>());
    *input = rest;
    I256::from_be_bytes(int_bytes.try_into().unwrap())
}

source

pub const fn from_le_bytes(bytes: [u8; 32]) -> Self

Create an integer value from its representation as a byte array in little endian.

Examples

let value = I256::from_le_bytes([
    0x1f, 0x1e, 0x1d, 0x1c, 0x1b, 0x1a, 0x19, 0x18, 0x17, 0x16, 0x15, 0x14, 0x13, 0x12, 0x11, 0x10,
    0x0f, 0x0e, 0x0d, 0x0c, 0x0b, 0x0a, 0x09, 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01, 0x00,
]);
assert_eq!(
    value,
    I256::from_words(
        0x00010203_04050607_08090a0b_0c0d0e0f,
        0x10111213_14151617_18191a1b_1c1d1e1f,
    ),
);

When starting from a slice rather than an array, fallible conversion APIs can be used:

fn read_le_i256(input: &mut &[u8]) -> I256 {
    let (int_bytes, rest) = input.split_at(std::mem::size_of::<I256>());
    *input = rest;
    I256::from_le_bytes(int_bytes.try_into().unwrap())
}

source

pub const fn from_ne_bytes(bytes: [u8; 32]) -> Self

Create an 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 = I256::from_ne_bytes(if cfg!(target_endian = "big") {
    [
        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
    ]
} else {
    [
        0x1f, 0x1e, 0x1d, 0x1c, 0x1b, 0x1a, 0x19, 0x18, 0x17, 0x16, 0x15, 0x14, 0x13, 0x12, 0x11, 0x10,
        0x0f, 0x0e, 0x0d, 0x0c, 0x0b, 0x0a, 0x09, 0x08, 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01, 0x00,
    ]
});
assert_eq!(
    value,
    I256::from_words(
        0x00010203_04050607_08090a0b_0c0d0e0f,
        0x10111213_14151617_18191a1b_1c1d1e1f,
    ),
);

When starting from a slice rather than an array, fallible conversion APIs can be used:

fn read_ne_i256(input: &mut &[u8]) -> I256 {
    let (int_bytes, rest) = input.split_at(std::mem::size_of::<I256>());
    *input = rest;
    I256::from_ne_bytes(int_bytes.try_into().unwrap())
}

source §

Basic usage:

assert_eq!(I256::from_str_hex("0x2A"), Ok(I256::new(42)));
assert_eq!(I256::from_str_hex("-0xa"), Ok(I256::new(-10)));

source

pub fn from_str_prefixed(src: &str) -> Result<Self, ParseIntError>

Converts a prefixed string slice in a base determined by the prefix to an integer.

The string is expected to be an optional + or - sign followed by the one of the supported prefixes and finally the digits. Leading and trailing whitespace represent an error. The base is determined based on the prefix:

0b: base 2
0o: base 8
0x: base 16
no prefix: base 10

Examples

Basic usage:

assert_eq!(I256::from_str_prefixed("-0b101"), Ok(I256::new(-0b101)));
assert_eq!(I256::from_str_prefixed("0o17"), Ok(I256::new(0o17)));
assert_eq!(I256::from_str_prefixed("-0xa"), Ok(I256::new(-0xa)));
assert_eq!(I256::from_str_prefixed("42"), Ok(I256::new(42)));