Trait bonsaidb::core::num_traits::PrimInt
source · pub trait PrimInt: Sized + Copy + Num<Output = Self, Output = Self, Output = Self, Output = Self> + NumCast + Bounded + PartialOrd + Ord + Eq + Not<Output = Self> + BitAnd<Output = Self> + BitOr<Output = Self> + BitXor<Output = Self> + Shl<usize, Output = Self> + Shr<usize, Output = Self> + CheckedAdd + CheckedSub + CheckedMul + CheckedDiv + Saturating {
Show 19 methods
// Required methods
fn count_ones(self) -> u32;
fn count_zeros(self) -> u32;
fn leading_zeros(self) -> u32;
fn trailing_zeros(self) -> u32;
fn rotate_left(self, n: u32) -> Self;
fn rotate_right(self, n: u32) -> Self;
fn signed_shl(self, n: u32) -> Self;
fn signed_shr(self, n: u32) -> Self;
fn unsigned_shl(self, n: u32) -> Self;
fn unsigned_shr(self, n: u32) -> Self;
fn swap_bytes(self) -> Self;
fn from_be(x: Self) -> Self;
fn from_le(x: Self) -> Self;
fn to_be(self) -> Self;
fn to_le(self) -> Self;
fn pow(self, exp: u32) -> Self;
// Provided methods
fn leading_ones(self) -> u32 { ... }
fn trailing_ones(self) -> u32 { ... }
fn reverse_bits(self) -> Self { ... }
}Expand description
Generic trait for primitive integers.
The PrimInt trait is an abstraction over the builtin primitive integer types (e.g., u8,
u32, isize, i128, …). It inherits the basic numeric traits and extends them with
bitwise operators and non-wrapping arithmetic.
The trait explicitly inherits Copy, Eq, Ord, and Sized. The intention is that all
types implementing this trait behave like primitive types that are passed by value by default
and behave like builtin integers. Furthermore, the types are expected to expose the integer
value in binary representation and support bitwise operators. The standard bitwise operations
(e.g., bitwise-and, bitwise-or, right-shift, left-shift) are inherited and the trait extends
these with introspective queries (e.g., PrimInt::count_ones(), PrimInt::leading_zeros()),
bitwise combinators (e.g., PrimInt::rotate_left()), and endianness converters (e.g.,
PrimInt::to_be()).
All PrimInt types are expected to be fixed-width binary integers. The width can be queried
via T::zero().count_zeros(). The trait currently lacks a way to query the width at
compile-time.
While a default implementation for all builtin primitive integers is provided, the trait is in no way restricted to these. Other integer types that fulfil the requirements are free to implement the trait was well.
This trait and many of the method names originate in the unstable core::num::Int trait from
the rust standard library. The original trait was never stabilized and thus removed from the
standard library.
Required Methods§
sourcefn count_ones(self) -> u32
fn count_ones(self) -> u32
Returns the number of ones in the binary representation of self.
Examples
use num_traits::PrimInt;
let n = 0b01001100u8;
assert_eq!(n.count_ones(), 3);sourcefn count_zeros(self) -> u32
fn count_zeros(self) -> u32
Returns the number of zeros in the binary representation of self.
Examples
use num_traits::PrimInt;
let n = 0b01001100u8;
assert_eq!(n.count_zeros(), 5);sourcefn leading_zeros(self) -> u32
fn leading_zeros(self) -> u32
Returns the number of leading zeros in the binary representation
of self.
Examples
use num_traits::PrimInt;
let n = 0b0101000u16;
assert_eq!(n.leading_zeros(), 10);sourcefn trailing_zeros(self) -> u32
fn trailing_zeros(self) -> u32
Returns the number of trailing zeros in the binary representation
of self.
Examples
use num_traits::PrimInt;
let n = 0b0101000u16;
assert_eq!(n.trailing_zeros(), 3);sourcefn rotate_left(self, n: u32) -> Self
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.
Examples
use num_traits::PrimInt;
let n = 0x0123456789ABCDEFu64;
let m = 0x3456789ABCDEF012u64;
assert_eq!(n.rotate_left(12), m);sourcefn rotate_right(self, n: u32) -> Self
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.
Examples
use num_traits::PrimInt;
let n = 0x0123456789ABCDEFu64;
let m = 0xDEF0123456789ABCu64;
assert_eq!(n.rotate_right(12), m);sourcefn signed_shl(self, n: u32) -> Self
fn signed_shl(self, n: u32) -> Self
Shifts the bits to the left by a specified amount, n, filling
zeros in the least significant bits.
This is bitwise equivalent to signed Shl.
Examples
use num_traits::PrimInt;
let n = 0x0123456789ABCDEFu64;
let m = 0x3456789ABCDEF000u64;
assert_eq!(n.signed_shl(12), m);sourcefn signed_shr(self, n: u32) -> Self
fn signed_shr(self, n: u32) -> Self
Shifts the bits to the right by a specified amount, n, copying
the “sign bit” in the most significant bits even for unsigned types.
This is bitwise equivalent to signed Shr.
Examples
use num_traits::PrimInt;
let n = 0xFEDCBA9876543210u64;
let m = 0xFFFFEDCBA9876543u64;
assert_eq!(n.signed_shr(12), m);sourcefn unsigned_shl(self, n: u32) -> Self
fn unsigned_shl(self, n: u32) -> Self
Shifts the bits to the left by a specified amount, n, filling
zeros in the least significant bits.
This is bitwise equivalent to unsigned Shl.
Examples
use num_traits::PrimInt;
let n = 0x0123456789ABCDEFi64;
let m = 0x3456789ABCDEF000i64;
assert_eq!(n.unsigned_shl(12), m);sourcefn unsigned_shr(self, n: u32) -> Self
fn unsigned_shr(self, n: u32) -> Self
Shifts the bits to the right by a specified amount, n, filling
zeros in the most significant bits.
This is bitwise equivalent to unsigned Shr.
Examples
use num_traits::PrimInt;
let n = -8i8; // 0b11111000
let m = 62i8; // 0b00111110
assert_eq!(n.unsigned_shr(2), m);sourcefn swap_bytes(self) -> Self
fn swap_bytes(self) -> Self
Reverses the byte order of the integer.
Examples
use num_traits::PrimInt;
let n = 0x0123456789ABCDEFu64;
let m = 0xEFCDAB8967452301u64;
assert_eq!(n.swap_bytes(), m);sourcefn from_be(x: Self) -> Self
fn from_be(x: Self) -> Self
Convert 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.
Examples
use num_traits::PrimInt;
let n = 0x0123456789ABCDEFu64;
if cfg!(target_endian = "big") {
assert_eq!(u64::from_be(n), n)
} else {
assert_eq!(u64::from_be(n), n.swap_bytes())
}sourcefn from_le(x: Self) -> Self
fn from_le(x: Self) -> Self
Convert 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
use num_traits::PrimInt;
let n = 0x0123456789ABCDEFu64;
if cfg!(target_endian = "little") {
assert_eq!(u64::from_le(n), n)
} else {
assert_eq!(u64::from_le(n), n.swap_bytes())
}sourcefn to_be(self) -> Self
fn to_be(self) -> Self
Convert self to big endian from the target’s endianness.
On big endian this is a no-op. On little endian the bytes are swapped.
Examples
use num_traits::PrimInt;
let n = 0x0123456789ABCDEFu64;
if cfg!(target_endian = "big") {
assert_eq!(n.to_be(), n)
} else {
assert_eq!(n.to_be(), n.swap_bytes())
}sourcefn to_le(self) -> Self
fn to_le(self) -> Self
Convert self to little endian from the target’s endianness.
On little endian this is a no-op. On big endian the bytes are swapped.
Examples
use num_traits::PrimInt;
let n = 0x0123456789ABCDEFu64;
if cfg!(target_endian = "little") {
assert_eq!(n.to_le(), n)
} else {
assert_eq!(n.to_le(), n.swap_bytes())
}Provided Methods§
sourcefn leading_ones(self) -> u32
fn leading_ones(self) -> u32
Returns the number of leading ones in the binary representation
of self.
Examples
use num_traits::PrimInt;
let n = 0xF00Du16;
assert_eq!(n.leading_ones(), 4);sourcefn trailing_ones(self) -> u32
fn trailing_ones(self) -> u32
Returns the number of trailing ones in the binary representation
of self.
Examples
use num_traits::PrimInt;
let n = 0xBEEFu16;
assert_eq!(n.trailing_ones(), 4);sourcefn reverse_bits(self) -> Self
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.
Examples
use num_traits::PrimInt;
let n = 0x12345678u32;
let m = 0x1e6a2c48u32;
assert_eq!(n.reverse_bits(), m);
assert_eq!(0u32.reverse_bits(), 0);