提交 3ff84fc5 编写于 作者: J Jorge Aparicio

impl {i,u}{8,16,32,64,size}

上级 8afcaabe
......@@ -46,6 +46,7 @@
use std::intrinsics;
use std::marker;
use std::mem;
#[cfg(stage0)]
use std::num::{Int, UnsignedInt};
use std::ptr;
use std::rc::Rc;
......
......@@ -23,7 +23,7 @@
use core::marker::PhantomData;
use core::ops::{Deref, DerefMut, Index, IndexMut};
use core::ptr::Unique;
use core::{slice, mem, ptr, cmp, num, raw};
use core::{slice, mem, ptr, cmp, raw};
use alloc::heap::{self, EMPTY};
use borrow::Borrow;
......@@ -105,7 +105,10 @@ struct MutNodeSlice<'a, K: 'a, V: 'a> {
/// Fails if `target_alignment` is not a power of two.
#[inline]
fn round_up_to_next(unrounded: usize, target_alignment: usize) -> usize {
assert!(num::UnsignedInt::is_power_of_two(target_alignment));
#[cfg(stage0)]
use core::num::UnsignedInt;
assert!(target_alignment.is_power_of_two());
(unrounded + target_alignment - 1) & !(target_alignment - 1)
}
......
......@@ -59,6 +59,7 @@
use core::iter::{repeat, FromIterator, IntoIterator};
use core::marker::PhantomData;
use core::mem;
#[cfg(stage0)]
use core::num::{Int, UnsignedInt};
use core::ops::{Index, IndexMut, Deref, Add};
use core::ops;
......
......@@ -25,6 +25,7 @@
use core::fmt;
use core::iter::{self, repeat, FromIterator, IntoIterator, RandomAccessIterator};
use core::mem;
#[cfg(stage0)]
use core::num::{Int, UnsignedInt};
use core::num::wrapping::WrappingOps;
use core::ops::{Index, IndexMut};
......
......@@ -708,6 +708,7 @@ fn is_negative(self) -> bool { self < 0 }
signed_int_impl! { i64 }
signed_int_impl! { int }
#[cfg(stage0)]
/// A built-in unsigned integer.
#[stable(feature = "rust1", since = "1.0.0")]
pub trait UnsignedInt: Int + WrappingOps {
......@@ -742,21 +743,1010 @@ fn checked_next_power_of_two(self) -> Option<Self> {
}
}
#[cfg(stage0)]
#[stable(feature = "rust1", since = "1.0.0")]
impl UnsignedInt for uint {}
#[cfg(stage0)]
#[stable(feature = "rust1", since = "1.0.0")]
impl UnsignedInt for u8 {}
#[cfg(stage0)]
#[stable(feature = "rust1", since = "1.0.0")]
impl UnsignedInt for u16 {}
#[cfg(stage0)]
#[stable(feature = "rust1", since = "1.0.0")]
impl UnsignedInt for u32 {}
#[cfg(stage0)]
#[stable(feature = "rust1", since = "1.0.0")]
impl UnsignedInt for u64 {}
// NB(japaric) I added this module to avoid adding several `cfg(not(stage0))`, and avoid name
// clashes between macros. We should move all the items inside this module into the outer scope
// once the `Int` trait is removed
#[cfg(not(stage0))]
mod inherent {
use intrinsics;
use mem::size_of;
use option::Option::{self, Some, None};
use super::wrapping::{OverflowingOps, WrappingOps};
// `Int` + `SignedInt` implemented for signed integers
macro_rules! int_impl {
($T:ty = $ActualT:ty, $UnsignedT:ty, $BITS:expr,
$add_with_overflow:path,
$sub_with_overflow:path,
$mul_with_overflow:path) => {
/// Returns the `0` value of this integer type.
// FIXME (#5527): Should be an associated constant
#[unstable(feature = "core",
reason = "unsure about its place in the world")]
#[inline]
pub fn zero() -> $T { 0 }
/// Returns the `1` value of this integer type.
// FIXME (#5527): Should be an associated constant
#[unstable(feature = "core",
reason = "unsure about its place in the world")]
#[inline]
pub fn one() -> $T { 1 }
/// Returns the smallest value that can be represented by this integer type.
// FIXME (#5527): Should be and associated constant
#[unstable(feature = "core",
reason = "unsure about its place in the world")]
#[inline]
pub fn min_value() -> $T { (-1 as $T) << ($BITS - 1) }
/// Returns the largest value that can be represented by this integer type.
// FIXME (#5527): Should be and associated constant
#[unstable(feature = "core",
reason = "unsure about its place in the world")]
#[inline]
pub fn max_value() -> $T { let min: $T = <$T>::min_value(); !min }
/// Returns the number of ones in the binary representation of `self`.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0b01001100u8;
///
/// assert_eq!(n.count_ones(), 3);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn count_ones(self) -> u32 { (self as $UnsignedT).count_ones() }
/// Returns the number of zeros in the binary representation of `self`.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0b01001100u8;
///
/// assert_eq!(n.count_zeros(), 5);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn count_zeros(self) -> u32 {
(!self).count_ones()
}
/// Returns the number of leading zeros in the binary representation
/// of `self`.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0b0101000u16;
///
/// assert_eq!(n.leading_zeros(), 10);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn leading_zeros(self) -> u32 { (self as $UnsignedT).leading_zeros() }
/// Returns the number of trailing zeros in the binary representation
/// of `self`.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0b0101000u16;
///
/// assert_eq!(n.trailing_zeros(), 3);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn trailing_zeros(self) -> u32 { (self as $UnsignedT).trailing_zeros() }
/// Shifts the bits to the left by a specified amount amount, `n`, wrapping
/// the truncated bits to the end of the resulting integer.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
/// let m = 0x3456789ABCDEF012u64;
///
/// assert_eq!(n.rotate_left(12), m);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn rotate_left(self, n: u32) -> $T { (self as $UnsignedT).rotate_left(n) as $T }
/// Shifts the bits to the right by a specified amount amount, `n`, wrapping
/// the truncated bits to the beginning of the resulting integer.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
/// let m = 0xDEF0123456789ABCu64;
///
/// assert_eq!(n.rotate_right(12), m);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn rotate_right(self, n: u32) -> $T { (self as $UnsignedT).rotate_right(n) as $T }
/// Reverses the byte order of the integer.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
/// let m = 0xEFCDAB8967452301u64;
///
/// assert_eq!(n.swap_bytes(), m);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn swap_bytes(self) -> $T { (self as $UnsignedT).swap_bytes() as $T }
/// 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
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
///
/// if cfg!(target_endian = "big") {
/// assert_eq!(Int::from_be(n), n)
/// } else {
/// assert_eq!(Int::from_be(n), n.swap_bytes())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn from_be(x: $T) -> $T {
if cfg!(target_endian = "big") { x } else { x.swap_bytes() }
}
/// 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
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
///
/// if cfg!(target_endian = "little") {
/// assert_eq!(Int::from_le(n), n)
/// } else {
/// assert_eq!(Int::from_le(n), n.swap_bytes())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn from_le(x: $T) -> $T {
if cfg!(target_endian = "little") { x } else { x.swap_bytes() }
}
/// 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
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
///
/// if cfg!(target_endian = "big") {
/// assert_eq!(n.to_be(), n)
/// } else {
/// assert_eq!(n.to_be(), n.swap_bytes())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn to_be(self) -> $T { // or not to be?
if cfg!(target_endian = "big") { self } else { self.swap_bytes() }
}
/// 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
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
///
/// if cfg!(target_endian = "little") {
/// assert_eq!(n.to_le(), n)
/// } else {
/// assert_eq!(n.to_le(), n.swap_bytes())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn to_le(self) -> $T {
if cfg!(target_endian = "little") { self } else { self.swap_bytes() }
}
/// Checked integer addition. Computes `self + other`, returning `None` if
/// overflow occurred.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!(5u16.checked_add(65530), Some(65535));
/// assert_eq!(6u16.checked_add(65530), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn checked_add(self, other: $T) -> Option<$T> {
checked_op!($T, $ActualT, $add_with_overflow, self, other)
}
/// Checked integer subtraction. Computes `self - other`, returning `None`
/// if underflow occurred.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!((-127i8).checked_sub(1), Some(-128));
/// assert_eq!((-128i8).checked_sub(1), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn checked_sub(self, other: $T) -> Option<$T> {
checked_op!($T, $ActualT, $sub_with_overflow, self, other)
}
/// Checked integer multiplication. Computes `self * other`, returning
/// `None` if underflow or overflow occurred.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!(5u8.checked_mul(51), Some(255));
/// assert_eq!(5u8.checked_mul(52), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn checked_mul(self, other: $T) -> Option<$T> {
checked_op!($T, $ActualT, $mul_with_overflow, self, other)
}
/// Checked integer division. Computes `self / other`, returning `None` if
/// `other == 0` or the operation results in underflow or overflow.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!((-127i8).checked_div(-1), Some(127));
/// assert_eq!((-128i8).checked_div(-1), None);
/// assert_eq!((1i8).checked_div(0), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn checked_div(self, v: $T) -> Option<$T> {
match v {
0 => None,
-1 if self == <$T>::min_value()
=> None,
v => Some(self / v),
}
}
/// Saturating integer addition. Computes `self + other`, saturating at
/// the numeric bounds instead of overflowing.
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn saturating_add(self, other: $T) -> $T {
match self.checked_add(other) {
Some(x) => x,
None if other >= <$T>::zero() => <$T>::max_value(),
None => <$T>::min_value(),
}
}
/// Saturating integer subtraction. Computes `self - other`, saturating at
/// the numeric bounds instead of overflowing.
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn saturating_sub(self, other: $T) -> $T {
match self.checked_sub(other) {
Some(x) => x,
None if other >= <$T>::zero() => <$T>::min_value(),
None => <$T>::max_value(),
}
}
/// Raises self to the power of `exp`, using exponentiation by squaring.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!(2.pow(4), 16);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn pow(self, mut exp: u32) -> $T {
let mut base = self;
let mut acc = <$T>::one();
let mut prev_base = self;
let mut base_oflo = false;
while exp > 0 {
if (exp & 1) == 1 {
if base_oflo {
// ensure overflow occurs in the same manner it
// would have otherwise (i.e. signal any exception
// it would have otherwise).
acc = acc * (prev_base * prev_base);
} else {
acc = acc * base;
}
}
prev_base = base;
let (new_base, new_base_oflo) = base.overflowing_mul(base);
base = new_base;
base_oflo = new_base_oflo;
exp /= 2;
}
acc
}
/// Computes the absolute value of `self`. `Int::min_value()` will be
/// returned if the number is `Int::min_value()`.
#[unstable(feature = "core", reason = "overflow in debug builds?")]
#[inline]
pub fn abs(self) -> $T {
if self.is_negative() { -self } else { 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
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn signum(self) -> $T {
match self {
n if n > 0 => 1,
0 => 0,
_ => -1,
}
}
/// Returns `true` if `self` is positive and `false` if the number
/// is zero or negative.
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn is_positive(self) -> bool { self > 0 }
/// Returns `true` if `self` is negative and `false` if the number
/// is zero or positive.
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn is_negative(self) -> bool { self < 0 }
}
}
#[lang = "i8"]
impl i8 {
int_impl! { i8 = i8, u8, 8,
intrinsics::i8_add_with_overflow,
intrinsics::i8_sub_with_overflow,
intrinsics::i8_mul_with_overflow }
}
#[lang = "i16"]
impl i16 {
int_impl! { i16 = i16, u16, 16,
intrinsics::i16_add_with_overflow,
intrinsics::i16_sub_with_overflow,
intrinsics::i16_mul_with_overflow }
}
#[lang = "i32"]
impl i32 {
int_impl! { i32 = i32, u32, 32,
intrinsics::i32_add_with_overflow,
intrinsics::i32_sub_with_overflow,
intrinsics::i32_mul_with_overflow }
}
#[lang = "i64"]
impl i64 {
int_impl! { i64 = i64, u64, 64,
intrinsics::i64_add_with_overflow,
intrinsics::i64_sub_with_overflow,
intrinsics::i64_mul_with_overflow }
}
#[cfg(target_pointer_width = "32")]
#[lang = "isize"]
impl isize {
int_impl! { int = i32, u32, 32,
intrinsics::i32_add_with_overflow,
intrinsics::i32_sub_with_overflow,
intrinsics::i32_mul_with_overflow }
}
#[cfg(target_pointer_width = "64")]
#[lang = "isize"]
impl isize {
int_impl! { int = i64, u64, 64,
intrinsics::i64_add_with_overflow,
intrinsics::i64_sub_with_overflow,
intrinsics::i64_mul_with_overflow }
}
// `Int` + `UnsignedInt` implemented for signed integers
macro_rules! uint_impl {
($T:ty = $ActualT:ty, $BITS:expr,
$ctpop:path,
$ctlz:path,
$cttz:path,
$bswap:path,
$add_with_overflow:path,
$sub_with_overflow:path,
$mul_with_overflow:path) => {
/// Returns the `0` value of this integer type.
// FIXME (#5527): Should be an associated constant
#[unstable(feature = "core",
reason = "unsure about its place in the world")]
#[inline]
pub fn zero() -> $T { 0 }
/// Returns the `1` value of this integer type.
// FIXME (#5527): Should be an associated constant
#[unstable(feature = "core",
reason = "unsure about its place in the world")]
#[inline]
pub fn one() -> $T { 1 }
/// Returns the smallest value that can be represented by this integer type.
// FIXME (#5527): Should be and associated constant
#[unstable(feature = "core",
reason = "unsure about its place in the world")]
#[inline]
pub fn min_value() -> $T { 0 }
/// Returns the largest value that can be represented by this integer type.
// FIXME (#5527): Should be and associated constant
#[unstable(feature = "core",
reason = "unsure about its place in the world")]
#[inline]
pub fn max_value() -> $T { -1 }
/// Returns the number of ones in the binary representation of `self`.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0b01001100u8;
///
/// assert_eq!(n.count_ones(), 3);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn count_ones(self) -> u32 { unsafe { $ctpop(self as $ActualT) as u32 } }
/// Returns the number of zeros in the binary representation of `self`.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0b01001100u8;
///
/// assert_eq!(n.count_zeros(), 5);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn count_zeros(self) -> u32 {
(!self).count_ones()
}
/// Returns the number of leading zeros in the binary representation
/// of `self`.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0b0101000u16;
///
/// assert_eq!(n.leading_zeros(), 10);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn leading_zeros(self) -> u32 { unsafe { $ctlz(self as $ActualT) as u32 } }
/// Returns the number of trailing zeros in the binary representation
/// of `self`.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0b0101000u16;
///
/// assert_eq!(n.trailing_zeros(), 3);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn trailing_zeros(self) -> u32 { unsafe { $cttz(self as $ActualT) as u32 } }
/// Shifts the bits to the left by a specified amount amount, `n`, wrapping
/// the truncated bits to the end of the resulting integer.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
/// let m = 0x3456789ABCDEF012u64;
///
/// assert_eq!(n.rotate_left(12), m);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn rotate_left(self, n: u32) -> $T {
// Protect against undefined behaviour for over-long bit shifts
let n = n % $BITS;
(self << n) | (self >> (($BITS - n) % $BITS))
}
/// Shifts the bits to the right by a specified amount amount, `n`, wrapping
/// the truncated bits to the beginning of the resulting integer.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
/// let m = 0xDEF0123456789ABCu64;
///
/// assert_eq!(n.rotate_right(12), m);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn rotate_right(self, n: u32) -> $T {
// Protect against undefined behaviour for over-long bit shifts
let n = n % $BITS;
(self >> n) | (self << (($BITS - n) % $BITS))
}
/// Reverses the byte order of the integer.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
/// let m = 0xEFCDAB8967452301u64;
///
/// assert_eq!(n.swap_bytes(), m);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn swap_bytes(self) -> $T { unsafe { $bswap(self as $ActualT) as $T } }
/// 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
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
///
/// if cfg!(target_endian = "big") {
/// assert_eq!(Int::from_be(n), n)
/// } else {
/// assert_eq!(Int::from_be(n), n.swap_bytes())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn from_be(x: $T) -> $T {
if cfg!(target_endian = "big") { x } else { x.swap_bytes() }
}
/// 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
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
///
/// if cfg!(target_endian = "little") {
/// assert_eq!(Int::from_le(n), n)
/// } else {
/// assert_eq!(Int::from_le(n), n.swap_bytes())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn from_le(x: $T) -> $T {
if cfg!(target_endian = "little") { x } else { x.swap_bytes() }
}
/// 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
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
///
/// if cfg!(target_endian = "big") {
/// assert_eq!(n.to_be(), n)
/// } else {
/// assert_eq!(n.to_be(), n.swap_bytes())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn to_be(self) -> $T { // or not to be?
if cfg!(target_endian = "big") { self } else { self.swap_bytes() }
}
/// 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
///
/// ```rust
/// use std::num::Int;
///
/// let n = 0x0123456789ABCDEFu64;
///
/// if cfg!(target_endian = "little") {
/// assert_eq!(n.to_le(), n)
/// } else {
/// assert_eq!(n.to_le(), n.swap_bytes())
/// }
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn to_le(self) -> $T {
if cfg!(target_endian = "little") { self } else { self.swap_bytes() }
}
/// Checked integer addition. Computes `self + other`, returning `None` if
/// overflow occurred.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!(5u16.checked_add(65530), Some(65535));
/// assert_eq!(6u16.checked_add(65530), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn checked_add(self, other: $T) -> Option<$T> {
checked_op!($T, $ActualT, $add_with_overflow, self, other)
}
/// Checked integer subtraction. Computes `self - other`, returning `None`
/// if underflow occurred.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!((-127i8).checked_sub(1), Some(-128));
/// assert_eq!((-128i8).checked_sub(1), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn checked_sub(self, other: $T) -> Option<$T> {
checked_op!($T, $ActualT, $sub_with_overflow, self, other)
}
/// Checked integer multiplication. Computes `self * other`, returning
/// `None` if underflow or overflow occurred.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!(5u8.checked_mul(51), Some(255));
/// assert_eq!(5u8.checked_mul(52), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn checked_mul(self, other: $T) -> Option<$T> {
checked_op!($T, $ActualT, $mul_with_overflow, self, other)
}
/// Checked integer division. Computes `self / other`, returning `None` if
/// `other == 0` or the operation results in underflow or overflow.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!((-127i8).checked_div(-1), Some(127));
/// assert_eq!((-128i8).checked_div(-1), None);
/// assert_eq!((1i8).checked_div(0), None);
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn checked_div(self, v: $T) -> Option<$T> {
match v {
0 => None,
v => Some(self / v),
}
}
/// Saturating integer addition. Computes `self + other`, saturating at
/// the numeric bounds instead of overflowing.
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn saturating_add(self, other: $T) -> $T {
match self.checked_add(other) {
Some(x) => x,
None if other >= <$T>::zero() => <$T>::max_value(),
None => <$T>::min_value(),
}
}
/// Saturating integer subtraction. Computes `self - other`, saturating at
/// the numeric bounds instead of overflowing.
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn saturating_sub(self, other: $T) -> $T {
match self.checked_sub(other) {
Some(x) => x,
None if other >= <$T>::zero() => <$T>::min_value(),
None => <$T>::max_value(),
}
}
/// Raises self to the power of `exp`, using exponentiation by squaring.
///
/// # Examples
///
/// ```rust
/// use std::num::Int;
///
/// assert_eq!(2.pow(4), 16);
/// ```
#[unstable(feature = "core",
reason = "pending integer conventions")]
#[inline]
pub fn pow(self, mut exp: u32) -> $T {
let mut base = self;
let mut acc = <$T>::one();
let mut prev_base = self;
let mut base_oflo = false;
while exp > 0 {
if (exp & 1) == 1 {
if base_oflo {
// ensure overflow occurs in the same manner it
// would have otherwise (i.e. signal any exception
// it would have otherwise).
acc = acc * (prev_base * prev_base);
} else {
acc = acc * base;
}
}
prev_base = base;
let (new_base, new_base_oflo) = base.overflowing_mul(base);
base = new_base;
base_oflo = new_base_oflo;
exp /= 2;
}
acc
}
/// Returns `true` iff `self == 2^k` for some `k`.
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn is_power_of_two(self) -> bool {
(self.wrapping_sub(<$T>::one())) & self == <$T>::zero() && !(self == <$T>::zero())
}
/// Returns the smallest power of two greater than or equal to `self`.
/// Unspecified behavior on overflow.
#[stable(feature = "rust1", since = "1.0.0")]
#[inline]
pub fn next_power_of_two(self) -> $T {
let bits = size_of::<$T>() * 8;
let one: $T = <$T>::one();
one << ((bits - self.wrapping_sub(one).leading_zeros() as usize) % bits)
}
/// Returns the smallest power of two greater than or equal to `n`. If the
/// next power of two is greater than the type's maximum value, `None` is
/// returned, otherwise the power of two is wrapped in `Some`.
#[stable(feature = "rust1", since = "1.0.0")]
pub fn checked_next_power_of_two(self) -> Option<$T> {
let npot = self.next_power_of_two();
if npot >= self {
Some(npot)
} else {
None
}
}
}
}
/// Swapping a single byte is a no-op. This is marked as `unsafe` for
/// consistency with the other `bswap` intrinsics.
unsafe fn bswap8(x: u8) -> u8 { x }
#[lang = "u8"]
impl u8 {
uint_impl! { u8 = u8, 8,
intrinsics::ctpop8,
intrinsics::ctlz8,
intrinsics::cttz8,
bswap8,
intrinsics::u8_add_with_overflow,
intrinsics::u8_sub_with_overflow,
intrinsics::u8_mul_with_overflow }
}
#[lang = "u16"]
impl u16 {
uint_impl! { u16 = u16, 16,
intrinsics::ctpop16,
intrinsics::ctlz16,
intrinsics::cttz16,
intrinsics::bswap16,
intrinsics::u16_add_with_overflow,
intrinsics::u16_sub_with_overflow,
intrinsics::u16_mul_with_overflow }
}
#[lang = "u32"]
impl u32 {
uint_impl! { u32 = u32, 32,
intrinsics::ctpop32,
intrinsics::ctlz32,
intrinsics::cttz32,
intrinsics::bswap32,
intrinsics::u32_add_with_overflow,
intrinsics::u32_sub_with_overflow,
intrinsics::u32_mul_with_overflow }
}
#[lang = "u64"]
impl u64 {
uint_impl! { u64 = u64, 64,
intrinsics::ctpop64,
intrinsics::ctlz64,
intrinsics::cttz64,
intrinsics::bswap64,
intrinsics::u64_add_with_overflow,
intrinsics::u64_sub_with_overflow,
intrinsics::u64_mul_with_overflow }
}
#[cfg(target_pointer_width = "32")]
#[lang = "usize"]
impl usize {
uint_impl! { uint = u32, 32,
intrinsics::ctpop32,
intrinsics::ctlz32,
intrinsics::cttz32,
intrinsics::bswap32,
intrinsics::u32_add_with_overflow,
intrinsics::u32_sub_with_overflow,
intrinsics::u32_mul_with_overflow }
}
#[cfg(target_pointer_width = "64")]
#[lang = "usize"]
impl usize {
uint_impl! { uint = u64, 64,
intrinsics::ctpop64,
intrinsics::ctlz64,
intrinsics::cttz64,
intrinsics::bswap64,
intrinsics::u64_add_with_overflow,
intrinsics::u64_sub_with_overflow,
intrinsics::u64_mul_with_overflow }
}
}
/// A generic trait for converting a value to a number.
#[unstable(feature = "core", reason = "trait is likely to be removed")]
pub trait ToPrimitive {
......
......@@ -123,7 +123,7 @@ pub fn new(items: &'a mut [Weighted<T>]) -> WeightedChoice<'a, T> {
// strictly speaking, this is subsumed by the total weight == 0 case
assert!(!items.is_empty(), "WeightedChoice::new called with no items");
let mut running_total = 0;
let mut running_total = 0_usize;
// we convert the list from individual weights to cumulative
// weights so we can binary search. This *could* drop elements
......
......@@ -23,6 +23,7 @@
use iter::{self, Iterator, ExactSizeIterator, IntoIterator, IteratorExt, FromIterator, Extend, Map};
use marker::Sized;
use mem::{self, replace};
#[cfg(stage0)]
use num::{Int, UnsignedInt};
use ops::{Deref, FnMut, Index, IndexMut};
use option::Option::{self, Some, None};
......
......@@ -19,6 +19,7 @@
use marker::{Copy, Send, Sync, Sized, self};
use mem::{min_align_of, size_of};
use mem;
#[cfg(stage0)]
use num::{Int, UnsignedInt};
use num::wrapping::{OverflowingOps, WrappingOps};
use ops::{Deref, DerefMut, Drop};
......
......@@ -23,7 +23,10 @@
use clone::Clone;
use cmp::{PartialOrd, PartialEq};
#[cfg(stage0)]
pub use core::num::{Int, SignedInt, UnsignedInt};
#[cfg(not(stage0))]
pub use core::num::{Int, SignedInt};
pub use core::num::{cast, FromPrimitive, NumCast, ToPrimitive};
pub use core::num::{from_int, from_i8, from_i16, from_i32, from_i64};
pub use core::num::{from_uint, from_u8, from_u16, from_u32, from_u64};
......
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