| macro_rules! int_impl { |
| ( |
| Self = $SelfT:ty, |
| ActualT = $ActualT:ident, |
| UnsignedT = $UnsignedT:ty, |
| |
| // There are all for use *only* in doc comments. |
| // As such, they're all passed as literals -- passing them as a string |
| // literal is fine if they need to be multiple code tokens. |
| // In non-comments, use the associated constants rather than these. |
| BITS = $BITS:literal, |
| BITS_MINUS_ONE = $BITS_MINUS_ONE:literal, |
| Min = $Min:literal, |
| Max = $Max:literal, |
| rot = $rot:literal, |
| rot_op = $rot_op:literal, |
| rot_result = $rot_result:literal, |
| swap_op = $swap_op:literal, |
| swapped = $swapped:literal, |
| reversed = $reversed:literal, |
| le_bytes = $le_bytes:literal, |
| be_bytes = $be_bytes:literal, |
| to_xe_bytes_doc = $to_xe_bytes_doc:expr, |
| from_xe_bytes_doc = $from_xe_bytes_doc:expr, |
| bound_condition = $bound_condition:literal, |
| ) => { |
| /// The smallest value that can be represented by this integer type |
| #[doc = concat!("(−2<sup>", $BITS_MINUS_ONE, "</sup>", $bound_condition, ").")] |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN, ", stringify!($Min), ");")] |
| /// ``` |
| #[stable(feature = "assoc_int_consts", since = "1.43.0")] |
| pub const MIN: Self = !Self::MAX; |
| |
| /// The largest value that can be represented by this integer type |
| #[doc = concat!("(2<sup>", $BITS_MINUS_ONE, "</sup> − 1", $bound_condition, ").")] |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX, ", stringify!($Max), ");")] |
| /// ``` |
| #[stable(feature = "assoc_int_consts", since = "1.43.0")] |
| pub const MAX: Self = (<$UnsignedT>::MAX >> 1) as Self; |
| |
| /// The size of this integer type in bits. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::BITS, ", stringify!($BITS), ");")] |
| /// ``` |
| #[stable(feature = "int_bits_const", since = "1.53.0")] |
| pub const BITS: u32 = <$UnsignedT>::BITS; |
| |
| /// Converts a string slice in a given base to an integer. |
| /// |
| /// The string is expected to be an optional `+` or `-` sign followed by digits. |
| /// Leading and trailing whitespace represent an error. Digits are a subset of these characters, |
| /// depending on `radix`: |
| /// |
| /// * `0-9` |
| /// * `a-z` |
| /// * `A-Z` |
| /// |
| /// # Panics |
| /// |
| /// This function panics if `radix` is not in the range from 2 to 36. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::from_str_radix(\"A\", 16), Ok(10));")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| pub fn from_str_radix(src: &str, radix: u32) -> Result<Self, ParseIntError> { |
| from_str_radix(src, radix) |
| } |
| |
| /// Returns the number of ones in the binary representation of `self`. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = 0b100_0000", stringify!($SelfT), ";")] |
| /// |
| /// assert_eq!(n.count_ones(), 1); |
| /// ``` |
| /// |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[doc(alias = "popcount")] |
| #[doc(alias = "popcnt")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn count_ones(self) -> u32 { (self as $UnsignedT).count_ones() } |
| |
| /// Returns the number of zeros in the binary representation of `self`. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.count_zeros(), 1);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn count_zeros(self) -> u32 { |
| (!self).count_ones() |
| } |
| |
| /// Returns the number of leading zeros in the binary representation of `self`. |
| /// |
| /// Depending on what you're doing with the value, you might also be interested in the |
| /// [`ilog2`] function which returns a consistent number, even if the type widens. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = -1", stringify!($SelfT), ";")] |
| /// |
| /// assert_eq!(n.leading_zeros(), 0); |
| /// ``` |
| #[doc = concat!("[`ilog2`]: ", stringify!($SelfT), "::ilog2")] |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn leading_zeros(self) -> u32 { |
| (self as $UnsignedT).leading_zeros() |
| } |
| |
| /// Returns the number of trailing zeros in the binary representation of `self`. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = -4", stringify!($SelfT), ";")] |
| /// |
| /// assert_eq!(n.trailing_zeros(), 2); |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn trailing_zeros(self) -> u32 { |
| (self as $UnsignedT).trailing_zeros() |
| } |
| |
| /// Returns the number of leading ones in the binary representation of `self`. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = -1", stringify!($SelfT), ";")] |
| /// |
| #[doc = concat!("assert_eq!(n.leading_ones(), ", stringify!($BITS), ");")] |
| /// ``` |
| #[stable(feature = "leading_trailing_ones", since = "1.46.0")] |
| #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn leading_ones(self) -> u32 { |
| (self as $UnsignedT).leading_ones() |
| } |
| |
| /// Returns the number of trailing ones in the binary representation of `self`. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = 3", stringify!($SelfT), ";")] |
| /// |
| /// assert_eq!(n.trailing_ones(), 2); |
| /// ``` |
| #[stable(feature = "leading_trailing_ones", since = "1.46.0")] |
| #[rustc_const_stable(feature = "leading_trailing_ones", since = "1.46.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn trailing_ones(self) -> u32 { |
| (self as $UnsignedT).trailing_ones() |
| } |
| |
| /// 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! |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = ", $rot_op, stringify!($SelfT), ";")] |
| #[doc = concat!("let m = ", $rot_result, ";")] |
| /// |
| #[doc = concat!("assert_eq!(n.rotate_left(", $rot, "), m);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn rotate_left(self, n: u32) -> Self { |
| (self as $UnsignedT).rotate_left(n) as 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! |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = ", $rot_result, stringify!($SelfT), ";")] |
| #[doc = concat!("let m = ", $rot_op, ";")] |
| /// |
| #[doc = concat!("assert_eq!(n.rotate_right(", $rot, "), m);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn rotate_right(self, n: u32) -> Self { |
| (self as $UnsignedT).rotate_right(n) as Self |
| } |
| |
| /// Reverses the byte order of the integer. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = ", $swap_op, stringify!($SelfT), ";")] |
| /// |
| /// let m = n.swap_bytes(); |
| /// |
| #[doc = concat!("assert_eq!(m, ", $swapped, ");")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn swap_bytes(self) -> Self { |
| (self as $UnsignedT).swap_bytes() as 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 |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = ", $swap_op, stringify!($SelfT), ";")] |
| /// let m = n.reverse_bits(); |
| /// |
| #[doc = concat!("assert_eq!(m, ", $reversed, ");")] |
| #[doc = concat!("assert_eq!(0, 0", stringify!($SelfT), ".reverse_bits());")] |
| /// ``` |
| #[stable(feature = "reverse_bits", since = "1.37.0")] |
| #[rustc_const_stable(feature = "reverse_bits", since = "1.37.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn reverse_bits(self) -> Self { |
| (self as $UnsignedT).reverse_bits() as Self |
| } |
| |
| /// Converts an integer from big endian to the target's endianness. |
| /// |
| /// On big endian this is a no-op. On little endian the bytes are swapped. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")] |
| /// |
| /// if cfg!(target_endian = "big") { |
| #[doc = concat!(" assert_eq!(", stringify!($SelfT), "::from_be(n), n)")] |
| /// } else { |
| #[doc = concat!(" assert_eq!(", stringify!($SelfT), "::from_be(n), n.swap_bytes())")] |
| /// } |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_conversions", since = "1.32.0")] |
| #[must_use] |
| #[inline] |
| pub const fn from_be(x: Self) -> Self { |
| #[cfg(target_endian = "big")] |
| { |
| x |
| } |
| #[cfg(not(target_endian = "big"))] |
| { |
| x.swap_bytes() |
| } |
| } |
| |
| /// 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. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")] |
| /// |
| /// if cfg!(target_endian = "little") { |
| #[doc = concat!(" assert_eq!(", stringify!($SelfT), "::from_le(n), n)")] |
| /// } else { |
| #[doc = concat!(" assert_eq!(", stringify!($SelfT), "::from_le(n), n.swap_bytes())")] |
| /// } |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_conversions", since = "1.32.0")] |
| #[must_use] |
| #[inline] |
| pub const fn from_le(x: Self) -> Self { |
| #[cfg(target_endian = "little")] |
| { |
| x |
| } |
| #[cfg(not(target_endian = "little"))] |
| { |
| x.swap_bytes() |
| } |
| } |
| |
| /// Converts `self` to big endian from the target's endianness. |
| /// |
| /// On big endian this is a no-op. On little endian the bytes are swapped. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")] |
| /// |
| /// 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")] |
| #[rustc_const_stable(feature = "const_int_conversions", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn to_be(self) -> Self { // or not to be? |
| #[cfg(target_endian = "big")] |
| { |
| self |
| } |
| #[cfg(not(target_endian = "big"))] |
| { |
| self.swap_bytes() |
| } |
| } |
| |
| /// 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. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = 0x1A", stringify!($SelfT), ";")] |
| /// |
| /// if cfg!(target_endian = "little") { |
| /// assert_eq!(n.to_le(), n) |
| /// } else { |
| /// assert_eq!(n.to_le(), n.swap_bytes()) |
| /// } |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_conversions", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn to_le(self) -> Self { |
| #[cfg(target_endian = "little")] |
| { |
| self |
| } |
| #[cfg(not(target_endian = "little"))] |
| { |
| self.swap_bytes() |
| } |
| } |
| |
| /// Checked integer addition. Computes `self + rhs`, returning `None` |
| /// if overflow occurred. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(1), Some(", stringify!($SelfT), "::MAX - 1));")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add(3), None);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_add(self, rhs: Self) -> Option<Self> { |
| let (a, b) = self.overflowing_add(rhs); |
| if unlikely!(b) {None} else {Some(a)} |
| } |
| |
| /// Unchecked integer addition. Computes `self + rhs`, assuming overflow |
| /// cannot occur. |
| /// |
| /// # Safety |
| /// |
| /// This results in undefined behavior when |
| #[doc = concat!("`self + rhs > ", stringify!($SelfT), "::MAX` or `self + rhs < ", stringify!($SelfT), "::MIN`,")] |
| /// i.e. when [`checked_add`] would return `None`. |
| /// |
| #[doc = concat!("[`checked_add`]: ", stringify!($SelfT), "::checked_add")] |
| #[unstable( |
| feature = "unchecked_math", |
| reason = "niche optimization path", |
| issue = "85122", |
| )] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[rustc_const_unstable(feature = "const_inherent_unchecked_arith", issue = "85122")] |
| #[inline(always)] |
| #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces |
| pub const unsafe fn unchecked_add(self, rhs: Self) -> Self { |
| // SAFETY: the caller must uphold the safety contract for |
| // `unchecked_add`. |
| unsafe { intrinsics::unchecked_add(self, rhs) } |
| } |
| |
| /// Checked addition with an unsigned integer. Computes `self + rhs`, |
| /// returning `None` if overflow occurred. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_add_unsigned(2), Some(3));")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).checked_add_unsigned(3), None);")] |
| /// ``` |
| #[stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_add_unsigned(self, rhs: $UnsignedT) -> Option<Self> { |
| let (a, b) = self.overflowing_add_unsigned(rhs); |
| if unlikely!(b) {None} else {Some(a)} |
| } |
| |
| /// Checked integer subtraction. Computes `self - rhs`, returning `None` if |
| /// overflow occurred. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).checked_sub(1), Some(", stringify!($SelfT), "::MIN + 1));")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).checked_sub(3), None);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_sub(self, rhs: Self) -> Option<Self> { |
| let (a, b) = self.overflowing_sub(rhs); |
| if unlikely!(b) {None} else {Some(a)} |
| } |
| |
| /// Unchecked integer subtraction. Computes `self - rhs`, assuming overflow |
| /// cannot occur. |
| /// |
| /// # Safety |
| /// |
| /// This results in undefined behavior when |
| #[doc = concat!("`self - rhs > ", stringify!($SelfT), "::MAX` or `self - rhs < ", stringify!($SelfT), "::MIN`,")] |
| /// i.e. when [`checked_sub`] would return `None`. |
| /// |
| #[doc = concat!("[`checked_sub`]: ", stringify!($SelfT), "::checked_sub")] |
| #[unstable( |
| feature = "unchecked_math", |
| reason = "niche optimization path", |
| issue = "85122", |
| )] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[rustc_const_unstable(feature = "const_inherent_unchecked_arith", issue = "85122")] |
| #[inline(always)] |
| #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces |
| pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self { |
| // SAFETY: the caller must uphold the safety contract for |
| // `unchecked_sub`. |
| unsafe { intrinsics::unchecked_sub(self, rhs) } |
| } |
| |
| /// Checked subtraction with an unsigned integer. Computes `self - rhs`, |
| /// returning `None` if overflow occurred. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".checked_sub_unsigned(2), Some(-1));")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).checked_sub_unsigned(3), None);")] |
| /// ``` |
| #[stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_sub_unsigned(self, rhs: $UnsignedT) -> Option<Self> { |
| let (a, b) = self.overflowing_sub_unsigned(rhs); |
| if unlikely!(b) {None} else {Some(a)} |
| } |
| |
| /// Checked integer multiplication. Computes `self * rhs`, returning `None` if |
| /// overflow occurred. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_mul(1), Some(", stringify!($SelfT), "::MAX));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_mul(2), None);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_mul(self, rhs: Self) -> Option<Self> { |
| let (a, b) = self.overflowing_mul(rhs); |
| if unlikely!(b) {None} else {Some(a)} |
| } |
| |
| /// Unchecked integer multiplication. Computes `self * rhs`, assuming overflow |
| /// cannot occur. |
| /// |
| /// # Safety |
| /// |
| /// This results in undefined behavior when |
| #[doc = concat!("`self * rhs > ", stringify!($SelfT), "::MAX` or `self * rhs < ", stringify!($SelfT), "::MIN`,")] |
| /// i.e. when [`checked_mul`] would return `None`. |
| /// |
| #[doc = concat!("[`checked_mul`]: ", stringify!($SelfT), "::checked_mul")] |
| #[unstable( |
| feature = "unchecked_math", |
| reason = "niche optimization path", |
| issue = "85122", |
| )] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[rustc_const_unstable(feature = "const_inherent_unchecked_arith", issue = "85122")] |
| #[inline(always)] |
| #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces |
| pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self { |
| // SAFETY: the caller must uphold the safety contract for |
| // `unchecked_mul`. |
| unsafe { intrinsics::unchecked_mul(self, rhs) } |
| } |
| |
| /// Checked integer division. Computes `self / rhs`, returning `None` if `rhs == 0` |
| /// or the division results in overflow. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).checked_div(-1), Some(", stringify!($Max), "));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_div(-1), None);")] |
| #[doc = concat!("assert_eq!((1", stringify!($SelfT), ").checked_div(0), None);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_div(self, rhs: Self) -> Option<Self> { |
| if unlikely!(rhs == 0 || ((self == Self::MIN) && (rhs == -1))) { |
| None |
| } else { |
| // SAFETY: div by zero and by INT_MIN have been checked above |
| Some(unsafe { intrinsics::unchecked_div(self, rhs) }) |
| } |
| } |
| |
| /// Checked Euclidean division. Computes `self.div_euclid(rhs)`, |
| /// returning `None` if `rhs == 0` or the division results in overflow. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).checked_div_euclid(-1), Some(", stringify!($Max), "));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_div_euclid(-1), None);")] |
| #[doc = concat!("assert_eq!((1", stringify!($SelfT), ").checked_div_euclid(0), None);")] |
| /// ``` |
| #[stable(feature = "euclidean_division", since = "1.38.0")] |
| #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_div_euclid(self, rhs: Self) -> Option<Self> { |
| // Using `&` helps LLVM see that it is the same check made in division. |
| if unlikely!(rhs == 0 || ((self == Self::MIN) & (rhs == -1))) { |
| None |
| } else { |
| Some(self.div_euclid(rhs)) |
| } |
| } |
| |
| /// Checked integer remainder. Computes `self % rhs`, returning `None` if |
| /// `rhs == 0` or the division results in overflow. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(2), Some(1));")] |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem(0), None);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_rem(-1), None);")] |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_rem(self, rhs: Self) -> Option<Self> { |
| if unlikely!(rhs == 0 || ((self == Self::MIN) && (rhs == -1))) { |
| None |
| } else { |
| // SAFETY: div by zero and by INT_MIN have been checked above |
| Some(unsafe { intrinsics::unchecked_rem(self, rhs) }) |
| } |
| } |
| |
| /// Checked Euclidean remainder. Computes `self.rem_euclid(rhs)`, returning `None` |
| /// if `rhs == 0` or the division results in overflow. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(2), Some(1));")] |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_rem_euclid(0), None);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_rem_euclid(-1), None);")] |
| /// ``` |
| #[stable(feature = "euclidean_division", since = "1.38.0")] |
| #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_rem_euclid(self, rhs: Self) -> Option<Self> { |
| // Using `&` helps LLVM see that it is the same check made in division. |
| if unlikely!(rhs == 0 || ((self == Self::MIN) & (rhs == -1))) { |
| None |
| } else { |
| Some(self.rem_euclid(rhs)) |
| } |
| } |
| |
| /// Checked negation. Computes `-self`, returning `None` if `self == MIN`. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_neg(), Some(-5));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_neg(), None);")] |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_neg(self) -> Option<Self> { |
| let (a, b) = self.overflowing_neg(); |
| if unlikely!(b) {None} else {Some(a)} |
| } |
| |
| /// Checked shift left. Computes `self << rhs`, returning `None` if `rhs` is larger |
| /// than or equal to the number of bits in `self`. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".checked_shl(4), Some(0x10));")] |
| #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".checked_shl(129), None);")] |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_shl(self, rhs: u32) -> Option<Self> { |
| let (a, b) = self.overflowing_shl(rhs); |
| if unlikely!(b) {None} else {Some(a)} |
| } |
| |
| /// Unchecked shift left. Computes `self << rhs`, assuming that |
| /// `rhs` is less than the number of bits in `self`. |
| /// |
| /// # Safety |
| /// |
| /// This results in undefined behavior if `rhs` is larger than |
| /// or equal to the number of bits in `self`, |
| /// i.e. when [`checked_shl`] would return `None`. |
| /// |
| #[doc = concat!("[`checked_shl`]: ", stringify!($SelfT), "::checked_shl")] |
| #[unstable( |
| feature = "unchecked_math", |
| reason = "niche optimization path", |
| issue = "85122", |
| )] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[rustc_const_unstable(feature = "const_inherent_unchecked_arith", issue = "85122")] |
| #[inline(always)] |
| #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces |
| pub const unsafe fn unchecked_shl(self, rhs: u32) -> Self { |
| // SAFETY: the caller must uphold the safety contract for |
| // `unchecked_shl`. |
| // Any legal shift amount is losslessly representable in the self type. |
| unsafe { intrinsics::unchecked_shl(self, rhs.try_into().ok().unwrap_unchecked()) } |
| } |
| |
| /// Checked shift right. Computes `self >> rhs`, returning `None` if `rhs` is |
| /// larger than or equal to the number of bits in `self`. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(4), Some(0x1));")] |
| #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(128), None);")] |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_shr(self, rhs: u32) -> Option<Self> { |
| let (a, b) = self.overflowing_shr(rhs); |
| if unlikely!(b) {None} else {Some(a)} |
| } |
| |
| /// Unchecked shift right. Computes `self >> rhs`, assuming that |
| /// `rhs` is less than the number of bits in `self`. |
| /// |
| /// # Safety |
| /// |
| /// This results in undefined behavior if `rhs` is larger than |
| /// or equal to the number of bits in `self`, |
| /// i.e. when [`checked_shr`] would return `None`. |
| /// |
| #[doc = concat!("[`checked_shr`]: ", stringify!($SelfT), "::checked_shr")] |
| #[unstable( |
| feature = "unchecked_math", |
| reason = "niche optimization path", |
| issue = "85122", |
| )] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[rustc_const_unstable(feature = "const_inherent_unchecked_arith", issue = "85122")] |
| #[inline(always)] |
| #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces |
| pub const unsafe fn unchecked_shr(self, rhs: u32) -> Self { |
| // SAFETY: the caller must uphold the safety contract for |
| // `unchecked_shr`. |
| // Any legal shift amount is losslessly representable in the self type. |
| unsafe { intrinsics::unchecked_shr(self, rhs.try_into().ok().unwrap_unchecked()) } |
| } |
| |
| /// Checked absolute value. Computes `self.abs()`, returning `None` if |
| /// `self == MIN`. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!((-5", stringify!($SelfT), ").checked_abs(), Some(5));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_abs(), None);")] |
| /// ``` |
| #[stable(feature = "no_panic_abs", since = "1.13.0")] |
| #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_abs(self) -> Option<Self> { |
| if self.is_negative() { |
| self.checked_neg() |
| } else { |
| Some(self) |
| } |
| } |
| |
| /// Checked exponentiation. Computes `self.pow(exp)`, returning `None` if |
| /// overflow occurred. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(8", stringify!($SelfT), ".checked_pow(2), Some(64));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_pow(2), None);")] |
| /// ``` |
| |
| #[stable(feature = "no_panic_pow", since = "1.34.0")] |
| #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_pow(self, mut exp: u32) -> Option<Self> { |
| if exp == 0 { |
| return Some(1); |
| } |
| let mut base = self; |
| let mut acc: Self = 1; |
| |
| while exp > 1 { |
| if (exp & 1) == 1 { |
| acc = try_opt!(acc.checked_mul(base)); |
| } |
| exp /= 2; |
| base = try_opt!(base.checked_mul(base)); |
| } |
| // since exp!=0, finally the exp must be 1. |
| // Deal with the final bit of the exponent separately, since |
| // squaring the base afterwards is not necessary and may cause a |
| // needless overflow. |
| acc.checked_mul(base) |
| } |
| |
| /// Saturating integer addition. Computes `self + rhs`, saturating at the numeric |
| /// bounds instead of overflowing. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_add(1), 101);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_add(100), ", stringify!($SelfT), "::MAX);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_add(-1), ", stringify!($SelfT), "::MIN);")] |
| /// ``` |
| |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn saturating_add(self, rhs: Self) -> Self { |
| intrinsics::saturating_add(self, rhs) |
| } |
| |
| /// Saturating addition with an unsigned integer. Computes `self + rhs`, |
| /// saturating at the numeric bounds instead of overflowing. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".saturating_add_unsigned(2), 3);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_add_unsigned(100), ", stringify!($SelfT), "::MAX);")] |
| /// ``` |
| #[stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_add_unsigned(self, rhs: $UnsignedT) -> Self { |
| // Overflow can only happen at the upper bound |
| // We cannot use `unwrap_or` here because it is not `const` |
| match self.checked_add_unsigned(rhs) { |
| Some(x) => x, |
| None => Self::MAX, |
| } |
| } |
| |
| /// Saturating integer subtraction. Computes `self - rhs`, saturating at the |
| /// numeric bounds instead of overflowing. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_sub(127), -27);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_sub(100), ", stringify!($SelfT), "::MIN);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_sub(-1), ", stringify!($SelfT), "::MAX);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn saturating_sub(self, rhs: Self) -> Self { |
| intrinsics::saturating_sub(self, rhs) |
| } |
| |
| /// Saturating subtraction with an unsigned integer. Computes `self - rhs`, |
| /// saturating at the numeric bounds instead of overflowing. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_sub_unsigned(127), -27);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_sub_unsigned(100), ", stringify!($SelfT), "::MIN);")] |
| /// ``` |
| #[stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_sub_unsigned(self, rhs: $UnsignedT) -> Self { |
| // Overflow can only happen at the lower bound |
| // We cannot use `unwrap_or` here because it is not `const` |
| match self.checked_sub_unsigned(rhs) { |
| Some(x) => x, |
| None => Self::MIN, |
| } |
| } |
| |
| /// Saturating integer negation. Computes `-self`, returning `MAX` if `self == MIN` |
| /// instead of overflowing. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_neg(), -100);")] |
| #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").saturating_neg(), 100);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_neg(), ", stringify!($SelfT), "::MAX);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_neg(), ", stringify!($SelfT), "::MIN + 1);")] |
| /// ``` |
| |
| #[stable(feature = "saturating_neg", since = "1.45.0")] |
| #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn saturating_neg(self) -> Self { |
| intrinsics::saturating_sub(0, self) |
| } |
| |
| /// Saturating absolute value. Computes `self.abs()`, returning `MAX` if `self == |
| /// MIN` instead of overflowing. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".saturating_abs(), 100);")] |
| #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").saturating_abs(), 100);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_abs(), ", stringify!($SelfT), "::MAX);")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).saturating_abs(), ", stringify!($SelfT), "::MAX);")] |
| /// ``` |
| |
| #[stable(feature = "saturating_neg", since = "1.45.0")] |
| #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_abs(self) -> Self { |
| if self.is_negative() { |
| self.saturating_neg() |
| } else { |
| self |
| } |
| } |
| |
| /// Saturating integer multiplication. Computes `self * rhs`, saturating at the |
| /// numeric bounds instead of overflowing. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".saturating_mul(12), 120);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_mul(10), ", stringify!($SelfT), "::MAX);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_mul(10), ", stringify!($SelfT), "::MIN);")] |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_saturating_int_methods", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_mul(self, rhs: Self) -> Self { |
| match self.checked_mul(rhs) { |
| Some(x) => x, |
| None => if (self < 0) == (rhs < 0) { |
| Self::MAX |
| } else { |
| Self::MIN |
| } |
| } |
| } |
| |
| /// Saturating integer division. Computes `self / rhs`, saturating at the |
| /// numeric bounds instead of overflowing. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".saturating_div(2), 2);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.saturating_div(-1), ", stringify!($SelfT), "::MIN + 1);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_div(-1), ", stringify!($SelfT), "::MAX);")] |
| /// |
| /// ``` |
| /// |
| /// ```should_panic |
| #[doc = concat!("let _ = 1", stringify!($SelfT), ".saturating_div(0);")] |
| /// |
| /// ``` |
| #[stable(feature = "saturating_div", since = "1.58.0")] |
| #[rustc_const_stable(feature = "saturating_div", since = "1.58.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_div(self, rhs: Self) -> Self { |
| match self.overflowing_div(rhs) { |
| (result, false) => result, |
| (_result, true) => Self::MAX, // MIN / -1 is the only possible saturating overflow |
| } |
| } |
| |
| /// Saturating integer exponentiation. Computes `self.pow(exp)`, |
| /// saturating at the numeric bounds instead of overflowing. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!((-4", stringify!($SelfT), ").saturating_pow(3), -64);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_pow(2), ", stringify!($SelfT), "::MAX);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.saturating_pow(3), ", stringify!($SelfT), "::MIN);")] |
| /// ``` |
| #[stable(feature = "no_panic_pow", since = "1.34.0")] |
| #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_pow(self, exp: u32) -> Self { |
| match self.checked_pow(exp) { |
| Some(x) => x, |
| None if self < 0 && exp % 2 == 1 => Self::MIN, |
| None => Self::MAX, |
| } |
| } |
| |
| /// Wrapping (modular) addition. Computes `self + rhs`, wrapping around at the |
| /// boundary of the type. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_add(27), 127);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_add(2), ", stringify!($SelfT), "::MIN + 1);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn wrapping_add(self, rhs: Self) -> Self { |
| intrinsics::wrapping_add(self, rhs) |
| } |
| |
| /// Wrapping (modular) addition with an unsigned integer. Computes |
| /// `self + rhs`, wrapping around at the boundary of the type. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_add_unsigned(27), 127);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.wrapping_add_unsigned(2), ", stringify!($SelfT), "::MIN + 1);")] |
| /// ``` |
| #[stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn wrapping_add_unsigned(self, rhs: $UnsignedT) -> Self { |
| self.wrapping_add(rhs as Self) |
| } |
| |
| /// Wrapping (modular) subtraction. Computes `self - rhs`, wrapping around at the |
| /// boundary of the type. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".wrapping_sub(127), -127);")] |
| #[doc = concat!("assert_eq!((-2", stringify!($SelfT), ").wrapping_sub(", stringify!($SelfT), "::MAX), ", stringify!($SelfT), "::MAX);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn wrapping_sub(self, rhs: Self) -> Self { |
| intrinsics::wrapping_sub(self, rhs) |
| } |
| |
| /// Wrapping (modular) subtraction with an unsigned integer. Computes |
| /// `self - rhs`, wrapping around at the boundary of the type. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".wrapping_sub_unsigned(127), -127);")] |
| #[doc = concat!("assert_eq!((-2", stringify!($SelfT), ").wrapping_sub_unsigned(", stringify!($UnsignedT), "::MAX), -1);")] |
| /// ``` |
| #[stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn wrapping_sub_unsigned(self, rhs: $UnsignedT) -> Self { |
| self.wrapping_sub(rhs as Self) |
| } |
| |
| /// Wrapping (modular) multiplication. Computes `self * rhs`, wrapping around at |
| /// the boundary of the type. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".wrapping_mul(12), 120);")] |
| /// assert_eq!(11i8.wrapping_mul(12), -124); |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn wrapping_mul(self, rhs: Self) -> Self { |
| intrinsics::wrapping_mul(self, rhs) |
| } |
| |
| /// 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: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div(10), 10);")] |
| /// assert_eq!((-128i8).wrapping_div(-1), -128); |
| /// ``` |
| #[stable(feature = "num_wrapping", since = "1.2.0")] |
| #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn wrapping_div(self, rhs: Self) -> Self { |
| self.overflowing_div(rhs).0 |
| } |
| |
| /// Wrapping Euclidean division. Computes `self.div_euclid(rhs)`, |
| /// wrapping around at the boundary of the type. |
| /// |
| /// Wrapping will only occur in `MIN / -1` on a signed type (where `MIN` is the negative minimal value |
| /// for the type). This is equivalent to `-MIN`, a positive value that is too large to represent in the |
| /// type. In this case, this method returns `MIN` itself. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is 0. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_div_euclid(10), 10);")] |
| /// assert_eq!((-128i8).wrapping_div_euclid(-1), -128); |
| /// ``` |
| #[stable(feature = "euclidean_division", since = "1.38.0")] |
| #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn wrapping_div_euclid(self, rhs: Self) -> Self { |
| self.overflowing_div_euclid(rhs).0 |
| } |
| |
| /// 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 `MIN` is the negative minimal value). In such a case, |
| /// this function returns `0`. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is 0. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem(10), 0);")] |
| /// assert_eq!((-128i8).wrapping_rem(-1), 0); |
| /// ``` |
| #[stable(feature = "num_wrapping", since = "1.2.0")] |
| #[rustc_const_stable(feature = "const_wrapping_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn wrapping_rem(self, rhs: Self) -> Self { |
| self.overflowing_rem(rhs).0 |
| } |
| |
| /// Wrapping Euclidean remainder. Computes `self.rem_euclid(rhs)`, wrapping around |
| /// at the boundary of the type. |
| /// |
| /// Wrapping will only occur in `MIN % -1` on a signed type (where `MIN` is the negative minimal value |
| /// for the type). In this case, this method returns 0. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is 0. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_rem_euclid(10), 0);")] |
| /// assert_eq!((-128i8).wrapping_rem_euclid(-1), 0); |
| /// ``` |
| #[stable(feature = "euclidean_division", since = "1.38.0")] |
| #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn wrapping_rem_euclid(self, rhs: Self) -> Self { |
| self.overflowing_rem_euclid(rhs).0 |
| } |
| |
| /// 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: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_neg(), -100);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.wrapping_neg(), ", stringify!($SelfT), "::MIN);")] |
| /// ``` |
| #[stable(feature = "num_wrapping", since = "1.2.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn wrapping_neg(self) -> Self { |
| (0 as $SelfT).wrapping_sub(self) |
| } |
| |
| /// Panic-free bitwise shift-left; yields `self << mask(rhs)`, where `mask` removes |
| /// any high-order bits of `rhs` that would cause the shift to exceed the bitwidth of the type. |
| /// |
| /// Note that this is *not* the same as a rotate-left; the RHS of a wrapping shift-left is restricted to |
| /// the range of the type, rather than the bits shifted out of the LHS being returned to the other end. |
| /// The primitive integer types all implement a [`rotate_left`](Self::rotate_left) function, |
| /// which may be what you want instead. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!((-1", stringify!($SelfT), ").wrapping_shl(7), -128);")] |
| #[doc = concat!("assert_eq!((-1", stringify!($SelfT), ").wrapping_shl(128), -1);")] |
| /// ``` |
| #[stable(feature = "num_wrapping", since = "1.2.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| #[rustc_allow_const_fn_unstable(const_inherent_unchecked_arith)] |
| pub const fn wrapping_shl(self, rhs: u32) -> Self { |
| // SAFETY: the masking by the bitsize of the type ensures that we do not shift |
| // out of bounds |
| unsafe { |
| self.unchecked_shl(rhs & (Self::BITS - 1)) |
| } |
| } |
| |
| /// Panic-free bitwise shift-right; yields `self >> mask(rhs)`, where `mask` |
| /// removes any high-order bits of `rhs` that would cause the shift to exceed the bitwidth of the type. |
| /// |
| /// Note that this is *not* the same as a rotate-right; the RHS of a wrapping shift-right is restricted |
| /// to the range of the type, rather than the bits shifted out of the LHS being returned to the other |
| /// end. The primitive integer types all implement a [`rotate_right`](Self::rotate_right) function, |
| /// which may be what you want instead. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!((-128", stringify!($SelfT), ").wrapping_shr(7), -1);")] |
| /// assert_eq!((-128i16).wrapping_shr(64), -128); |
| /// ``` |
| #[stable(feature = "num_wrapping", since = "1.2.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| #[rustc_allow_const_fn_unstable(const_inherent_unchecked_arith)] |
| pub const fn wrapping_shr(self, rhs: u32) -> Self { |
| // SAFETY: the masking by the bitsize of the type ensures that we do not shift |
| // out of bounds |
| unsafe { |
| self.unchecked_shr(rhs & (Self::BITS - 1)) |
| } |
| } |
| |
| /// 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: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".wrapping_abs(), 100);")] |
| #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").wrapping_abs(), 100);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.wrapping_abs(), ", stringify!($SelfT), "::MIN);")] |
| /// assert_eq!((-128i8).wrapping_abs() as u8, 128); |
| /// ``` |
| #[stable(feature = "no_panic_abs", since = "1.13.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[allow(unused_attributes)] |
| #[inline] |
| pub const fn wrapping_abs(self) -> Self { |
| if self.is_negative() { |
| self.wrapping_neg() |
| } else { |
| self |
| } |
| } |
| |
| /// Computes the absolute value of `self` without any wrapping |
| /// or panicking. |
| /// |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".unsigned_abs(), 100", stringify!($UnsignedT), ");")] |
| #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").unsigned_abs(), 100", stringify!($UnsignedT), ");")] |
| /// assert_eq!((-128i8).unsigned_abs(), 128u8); |
| /// ``` |
| #[stable(feature = "unsigned_abs", since = "1.51.0")] |
| #[rustc_const_stable(feature = "unsigned_abs", since = "1.51.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn unsigned_abs(self) -> $UnsignedT { |
| self.wrapping_abs() as $UnsignedT |
| } |
| |
| /// Wrapping (modular) exponentiation. Computes `self.pow(exp)`, |
| /// wrapping around at the boundary of the type. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".wrapping_pow(4), 81);")] |
| /// assert_eq!(3i8.wrapping_pow(5), -13); |
| /// assert_eq!(3i8.wrapping_pow(6), -39); |
| /// ``` |
| #[stable(feature = "no_panic_pow", since = "1.34.0")] |
| #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn wrapping_pow(self, mut exp: u32) -> Self { |
| if exp == 0 { |
| return 1; |
| } |
| let mut base = self; |
| let mut acc: Self = 1; |
| |
| while exp > 1 { |
| if (exp & 1) == 1 { |
| acc = acc.wrapping_mul(base); |
| } |
| exp /= 2; |
| base = base.wrapping_mul(base); |
| } |
| |
| // since exp!=0, finally the exp must be 1. |
| // Deal with the final bit of the exponent separately, since |
| // squaring the base afterwards is not necessary and may cause a |
| // needless overflow. |
| acc.wrapping_mul(base) |
| } |
| |
| /// 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: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_add(2), (7, false));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.overflowing_add(1), (", stringify!($SelfT), "::MIN, true));")] |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn overflowing_add(self, rhs: Self) -> (Self, bool) { |
| let (a, b) = intrinsics::add_with_overflow(self as $ActualT, rhs as $ActualT); |
| (a as Self, b) |
| } |
| |
| /// Calculates `self` + `rhs` + `carry` and checks for overflow. |
| /// |
| /// Performs "ternary addition" of two integer operands and a carry-in |
| /// bit, and returns a tuple of the sum along with a boolean indicating |
| /// whether an arithmetic overflow would occur. On overflow, the wrapped |
| /// value is returned. |
| /// |
| /// This allows chaining together multiple additions to create a wider |
| /// addition, and can be useful for bignum addition. This method should |
| /// only be used for the most significant word; for the less significant |
| /// words the unsigned method |
| #[doc = concat!("[`", stringify!($UnsignedT), "::carrying_add`]")] |
| /// should be used. |
| /// |
| /// The output boolean returned by this method is *not* a carry flag, |
| /// and should *not* be added to a more significant word. |
| /// |
| /// If the input carry is false, this method is equivalent to |
| /// [`overflowing_add`](Self::overflowing_add). |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// #![feature(bigint_helper_methods)] |
| /// // Only the most significant word is signed. |
| /// // |
| #[doc = concat!("// 10 MAX (a = 10 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")] |
| #[doc = concat!("// + -5 9 (b = -5 × 2^", stringify!($BITS), " + 9)")] |
| /// // --------- |
| #[doc = concat!("// 6 8 (sum = 6 × 2^", stringify!($BITS), " + 8)")] |
| /// |
| #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($UnsignedT), ") = (10, ", stringify!($UnsignedT), "::MAX);")] |
| #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($UnsignedT), ") = (-5, 9);")] |
| /// let carry0 = false; |
| /// |
| #[doc = concat!("// ", stringify!($UnsignedT), "::carrying_add for the less significant words")] |
| /// let (sum0, carry1) = a0.carrying_add(b0, carry0); |
| /// assert_eq!(carry1, true); |
| /// |
| #[doc = concat!("// ", stringify!($SelfT), "::carrying_add for the most significant word")] |
| /// let (sum1, overflow) = a1.carrying_add(b1, carry1); |
| /// assert_eq!(overflow, false); |
| /// |
| /// assert_eq!((sum1, sum0), (6, 8)); |
| /// ``` |
| #[unstable(feature = "bigint_helper_methods", issue = "85532")] |
| #[rustc_const_unstable(feature = "const_bigint_helper_methods", issue = "85532")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn carrying_add(self, rhs: Self, carry: bool) -> (Self, bool) { |
| // note: longer-term this should be done via an intrinsic. |
| // note: no intermediate overflow is required (https://github.com/rust-lang/rust/issues/85532#issuecomment-1032214946). |
| let (a, b) = self.overflowing_add(rhs); |
| let (c, d) = a.overflowing_add(carry as $SelfT); |
| (c, b != d) |
| } |
| |
| /// Calculates `self` + `rhs` with an unsigned `rhs` |
| /// |
| /// Returns a tuple of the addition along with a boolean indicating |
| /// whether an arithmetic overflow would occur. If an overflow would |
| /// have occurred then the wrapped value is returned. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_add_unsigned(2), (3, false));")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN).overflowing_add_unsigned(", stringify!($UnsignedT), "::MAX), (", stringify!($SelfT), "::MAX, false));")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).overflowing_add_unsigned(3), (", stringify!($SelfT), "::MIN, true));")] |
| /// ``` |
| #[stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn overflowing_add_unsigned(self, rhs: $UnsignedT) -> (Self, bool) { |
| let rhs = rhs as Self; |
| let (res, overflowed) = self.overflowing_add(rhs); |
| (res, overflowed ^ (rhs < 0)) |
| } |
| |
| /// Calculates `self` - `rhs` |
| /// |
| /// Returns a tuple of the subtraction along with a boolean indicating whether an arithmetic overflow |
| /// would occur. If an overflow would have occurred then the wrapped value is returned. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_sub(2), (3, false));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_sub(1), (", stringify!($SelfT), "::MAX, true));")] |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn overflowing_sub(self, rhs: Self) -> (Self, bool) { |
| let (a, b) = intrinsics::sub_with_overflow(self as $ActualT, rhs as $ActualT); |
| (a as Self, b) |
| } |
| |
| /// Calculates `self` − `rhs` − `borrow` and checks for |
| /// overflow. |
| /// |
| /// Performs "ternary subtraction" by subtracting both an integer |
| /// operand and a borrow-in bit from `self`, and returns a tuple of the |
| /// difference along with a boolean indicating whether an arithmetic |
| /// overflow would occur. On overflow, the wrapped value is returned. |
| /// |
| /// This allows chaining together multiple subtractions to create a |
| /// wider subtraction, and can be useful for bignum subtraction. This |
| /// method should only be used for the most significant word; for the |
| /// less significant words the unsigned method |
| #[doc = concat!("[`", stringify!($UnsignedT), "::borrowing_sub`]")] |
| /// should be used. |
| /// |
| /// The output boolean returned by this method is *not* a borrow flag, |
| /// and should *not* be subtracted from a more significant word. |
| /// |
| /// If the input borrow is false, this method is equivalent to |
| /// [`overflowing_sub`](Self::overflowing_sub). |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// #![feature(bigint_helper_methods)] |
| /// // Only the most significant word is signed. |
| /// // |
| #[doc = concat!("// 6 8 (a = 6 × 2^", stringify!($BITS), " + 8)")] |
| #[doc = concat!("// - -5 9 (b = -5 × 2^", stringify!($BITS), " + 9)")] |
| /// // --------- |
| #[doc = concat!("// 10 MAX (diff = 10 × 2^", stringify!($BITS), " + 2^", stringify!($BITS), " - 1)")] |
| /// |
| #[doc = concat!("let (a1, a0): (", stringify!($SelfT), ", ", stringify!($UnsignedT), ") = (6, 8);")] |
| #[doc = concat!("let (b1, b0): (", stringify!($SelfT), ", ", stringify!($UnsignedT), ") = (-5, 9);")] |
| /// let borrow0 = false; |
| /// |
| #[doc = concat!("// ", stringify!($UnsignedT), "::borrowing_sub for the less significant words")] |
| /// let (diff0, borrow1) = a0.borrowing_sub(b0, borrow0); |
| /// assert_eq!(borrow1, true); |
| /// |
| #[doc = concat!("// ", stringify!($SelfT), "::borrowing_sub for the most significant word")] |
| /// let (diff1, overflow) = a1.borrowing_sub(b1, borrow1); |
| /// assert_eq!(overflow, false); |
| /// |
| #[doc = concat!("assert_eq!((diff1, diff0), (10, ", stringify!($UnsignedT), "::MAX));")] |
| /// ``` |
| #[unstable(feature = "bigint_helper_methods", issue = "85532")] |
| #[rustc_const_unstable(feature = "const_bigint_helper_methods", issue = "85532")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn borrowing_sub(self, rhs: Self, borrow: bool) -> (Self, bool) { |
| // note: longer-term this should be done via an intrinsic. |
| // note: no intermediate overflow is required (https://github.com/rust-lang/rust/issues/85532#issuecomment-1032214946). |
| let (a, b) = self.overflowing_sub(rhs); |
| let (c, d) = a.overflowing_sub(borrow as $SelfT); |
| (c, b != d) |
| } |
| |
| /// Calculates `self` - `rhs` with an unsigned `rhs` |
| /// |
| /// Returns a tuple of the subtraction along with a boolean indicating |
| /// whether an arithmetic overflow would occur. If an overflow would |
| /// have occurred then the wrapped value is returned. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".overflowing_sub_unsigned(2), (-1, false));")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX).overflowing_sub_unsigned(", stringify!($UnsignedT), "::MAX), (", stringify!($SelfT), "::MIN, false));")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).overflowing_sub_unsigned(3), (", stringify!($SelfT), "::MAX, true));")] |
| /// ``` |
| #[stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[rustc_const_stable(feature = "mixed_integer_ops", since = "1.66.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn overflowing_sub_unsigned(self, rhs: $UnsignedT) -> (Self, bool) { |
| let rhs = rhs as Self; |
| let (res, overflowed) = self.overflowing_sub(rhs); |
| (res, overflowed ^ (rhs < 0)) |
| } |
| |
| /// Calculates the multiplication of `self` and `rhs`. |
| /// |
| /// Returns a tuple of the multiplication along with a boolean indicating whether an arithmetic overflow |
| /// would occur. If an overflow would have occurred then the wrapped value is returned. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_mul(2), (10, false));")] |
| /// assert_eq!(1_000_000_000i32.overflowing_mul(10), (1410065408, true)); |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| pub const fn overflowing_mul(self, rhs: Self) -> (Self, bool) { |
| let (a, b) = intrinsics::mul_with_overflow(self as $ActualT, rhs as $ActualT); |
| (a as Self, b) |
| } |
| |
| /// Calculates the divisor when `self` is divided by `rhs`. |
| /// |
| /// Returns a tuple of the divisor along with a boolean indicating whether an arithmetic overflow would |
| /// occur. If an overflow would occur then self is returned. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is 0. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div(2), (2, false));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_div(-1), (", stringify!($SelfT), "::MIN, true));")] |
| /// ``` |
| #[inline] |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| pub const fn overflowing_div(self, rhs: Self) -> (Self, bool) { |
| // Using `&` helps LLVM see that it is the same check made in division. |
| if unlikely!((self == Self::MIN) & (rhs == -1)) { |
| (self, true) |
| } else { |
| (self / rhs, false) |
| } |
| } |
| |
| /// 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: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_div_euclid(2), (2, false));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_div_euclid(-1), (", stringify!($SelfT), "::MIN, true));")] |
| /// ``` |
| #[inline] |
| #[stable(feature = "euclidean_division", since = "1.38.0")] |
| #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| pub const fn overflowing_div_euclid(self, rhs: Self) -> (Self, bool) { |
| // Using `&` helps LLVM see that it is the same check made in division. |
| if unlikely!((self == Self::MIN) & (rhs == -1)) { |
| (self, true) |
| } else { |
| (self.div_euclid(rhs), false) |
| } |
| } |
| |
| /// Calculates the remainder when `self` is divided by `rhs`. |
| /// |
| /// Returns a tuple of the remainder after dividing along with a boolean indicating whether an |
| /// arithmetic overflow would occur. If an overflow would occur then 0 is returned. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is 0. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem(2), (1, false));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_rem(-1), (0, true));")] |
| /// ``` |
| #[inline] |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| pub const fn overflowing_rem(self, rhs: Self) -> (Self, bool) { |
| if unlikely!(rhs == -1) { |
| (0, self == Self::MIN) |
| } else { |
| (self % rhs, false) |
| } |
| } |
| |
| |
| /// Overflowing Euclidean remainder. Calculates `self.rem_euclid(rhs)`. |
| /// |
| /// Returns a tuple of the remainder after dividing along with a boolean indicating whether an |
| /// arithmetic overflow would occur. If an overflow would occur then 0 is returned. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is 0. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem_euclid(2), (1, false));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_rem_euclid(-1), (0, true));")] |
| /// ``` |
| #[stable(feature = "euclidean_division", since = "1.38.0")] |
| #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn overflowing_rem_euclid(self, rhs: Self) -> (Self, bool) { |
| if unlikely!(rhs == -1) { |
| (0, self == Self::MIN) |
| } else { |
| (self.rem_euclid(rhs), false) |
| } |
| } |
| |
| |
| /// Negates self, overflowing if this is equal to the minimum value. |
| /// |
| /// Returns a tuple of the negated version of self along with a boolean indicating whether an overflow |
| /// happened. If `self` is the minimum value (e.g., `i32::MIN` for values of type `i32`), then the |
| /// minimum value will be returned again and `true` will be returned for an overflow happening. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".overflowing_neg(), (-2, false));")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_neg(), (", stringify!($SelfT), "::MIN, true));")] |
| /// ``` |
| #[inline] |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[allow(unused_attributes)] |
| pub const fn overflowing_neg(self) -> (Self, bool) { |
| if unlikely!(self == Self::MIN) { |
| (Self::MIN, true) |
| } else { |
| (-self, false) |
| } |
| } |
| |
| /// 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: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(0x1", stringify!($SelfT),".overflowing_shl(4), (0x10, false));")] |
| /// assert_eq!(0x1i32.overflowing_shl(36), (0x10, true)); |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn overflowing_shl(self, rhs: u32) -> (Self, bool) { |
| (self.wrapping_shl(rhs), rhs >= Self::BITS) |
| } |
| |
| /// Shifts self right by `rhs` bits. |
| /// |
| /// Returns a tuple of the shifted version of self along with a boolean indicating whether the shift |
| /// value was larger than or equal to the number of bits. If the shift value is too large, then value is |
| /// masked (N-1) where N is the number of bits, and this value is then used to perform the shift. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shr(4), (0x1, false));")] |
| /// assert_eq!(0x10i32.overflowing_shr(36), (0x1, true)); |
| /// ``` |
| #[stable(feature = "wrapping", since = "1.7.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn overflowing_shr(self, rhs: u32) -> (Self, bool) { |
| (self.wrapping_shr(rhs), rhs >= Self::BITS) |
| } |
| |
| /// 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 |
| #[doc = concat!("(e.g., ", stringify!($SelfT), "::MIN for values of type ", stringify!($SelfT), "),")] |
| /// then the minimum value will be returned again and true will be returned |
| /// for an overflow happening. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".overflowing_abs(), (10, false));")] |
| #[doc = concat!("assert_eq!((-10", stringify!($SelfT), ").overflowing_abs(), (10, false));")] |
| #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN).overflowing_abs(), (", stringify!($SelfT), "::MIN, true));")] |
| /// ``` |
| #[stable(feature = "no_panic_abs", since = "1.13.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn overflowing_abs(self) -> (Self, bool) { |
| (self.wrapping_abs(), self == Self::MIN) |
| } |
| |
| /// 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: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(3", stringify!($SelfT), ".overflowing_pow(4), (81, false));")] |
| /// assert_eq!(3i8.overflowing_pow(5), (-13, true)); |
| /// ``` |
| #[stable(feature = "no_panic_pow", since = "1.34.0")] |
| #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn overflowing_pow(self, mut exp: u32) -> (Self, bool) { |
| if exp == 0 { |
| return (1,false); |
| } |
| let mut base = self; |
| let mut acc: Self = 1; |
| let mut overflown = false; |
| // Scratch space for storing results of overflowing_mul. |
| let mut r; |
| |
| while exp > 1 { |
| if (exp & 1) == 1 { |
| r = acc.overflowing_mul(base); |
| acc = r.0; |
| overflown |= r.1; |
| } |
| exp /= 2; |
| r = base.overflowing_mul(base); |
| base = r.0; |
| overflown |= r.1; |
| } |
| |
| // since exp!=0, finally the exp must be 1. |
| // Deal with the final bit of the exponent separately, since |
| // squaring the base afterwards is not necessary and may cause a |
| // needless overflow. |
| r = acc.overflowing_mul(base); |
| r.1 |= overflown; |
| r |
| } |
| |
| /// Raises self to the power of `exp`, using exponentiation by squaring. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let x: ", stringify!($SelfT), " = 2; // or any other integer type")] |
| /// |
| /// assert_eq!(x.pow(5), 32); |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[rustc_inherit_overflow_checks] |
| pub const fn pow(self, mut exp: u32) -> Self { |
| if exp == 0 { |
| return 1; |
| } |
| let mut base = self; |
| let mut acc = 1; |
| |
| while exp > 1 { |
| if (exp & 1) == 1 { |
| acc = acc * base; |
| } |
| exp /= 2; |
| base = base * base; |
| } |
| |
| // since exp!=0, finally the exp must be 1. |
| // Deal with the final bit of the exponent separately, since |
| // squaring the base afterwards is not necessary and may cause a |
| // needless overflow. |
| acc * base |
| } |
| |
| /// 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: |
| /// |
| /// ``` |
| #[doc = concat!("let a: ", stringify!($SelfT), " = 7; // or any other integer type")] |
| /// let b = 4; |
| /// |
| /// assert_eq!(a.div_euclid(b), 1); // 7 >= 4 * 1 |
| /// assert_eq!(a.div_euclid(-b), -1); // 7 >= -4 * -1 |
| /// assert_eq!((-a).div_euclid(b), -2); // -7 >= 4 * -2 |
| /// assert_eq!((-a).div_euclid(-b), 2); // -7 >= -4 * 2 |
| /// ``` |
| #[stable(feature = "euclidean_division", since = "1.38.0")] |
| #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[rustc_inherit_overflow_checks] |
| pub const fn div_euclid(self, rhs: Self) -> Self { |
| let q = self / rhs; |
| if self % rhs < 0 { |
| return if rhs > 0 { q - 1 } else { q + 1 } |
| } |
| q |
| } |
| |
| |
| /// Calculates the least nonnegative remainder of `self (mod rhs)`. |
| /// |
| /// This is done as if by the Euclidean division algorithm -- given |
| /// `r = self.rem_euclid(rhs)`, `self = rhs * self.div_euclid(rhs) + r`, and |
| /// `0 <= r < abs(rhs)`. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is 0 or the division results in overflow. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let a: ", stringify!($SelfT), " = 7; // or any other integer type")] |
| /// let b = 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); |
| /// ``` |
| #[stable(feature = "euclidean_division", since = "1.38.0")] |
| #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[rustc_inherit_overflow_checks] |
| pub const fn rem_euclid(self, rhs: Self) -> Self { |
| let r = self % rhs; |
| if r < 0 { |
| // Semantically equivalent to `if rhs < 0 { r - rhs } else { r + rhs }`. |
| // If `rhs` is not `Self::MIN`, then `r + abs(rhs)` will not overflow |
| // and is clearly equivalent, because `r` is negative. |
| // Otherwise, `rhs` is `Self::MIN`, then we have |
| // `r.wrapping_add(Self::MIN.wrapping_abs())`, which evaluates |
| // to `r.wrapping_add(Self::MIN)`, which is equivalent to |
| // `r - Self::MIN`, which is what we wanted (and will not overflow |
| // for negative `r`). |
| r.wrapping_add(rhs.wrapping_abs()) |
| } else { |
| r |
| } |
| } |
| |
| /// Calculates the quotient of `self` and `rhs`, rounding the result towards negative infinity. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is zero. |
| /// |
| /// ## Overflow behavior |
| /// |
| /// On overflow, this function will panic if overflow checks are enabled (default in debug |
| /// mode) and wrap if overflow checks are disabled (default in release mode). |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| /// #![feature(int_roundings)] |
| #[doc = concat!("let a: ", stringify!($SelfT)," = 8;")] |
| /// let b = 3; |
| /// |
| /// assert_eq!(a.div_floor(b), 2); |
| /// assert_eq!(a.div_floor(-b), -3); |
| /// assert_eq!((-a).div_floor(b), -3); |
| /// assert_eq!((-a).div_floor(-b), 2); |
| /// ``` |
| #[unstable(feature = "int_roundings", issue = "88581")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[rustc_inherit_overflow_checks] |
| pub const fn div_floor(self, rhs: Self) -> Self { |
| let d = self / rhs; |
| let r = self % rhs; |
| if (r > 0 && rhs < 0) || (r < 0 && rhs > 0) { |
| d - 1 |
| } else { |
| d |
| } |
| } |
| |
| /// Calculates the quotient of `self` and `rhs`, rounding the result towards positive infinity. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is zero. |
| /// |
| /// ## Overflow behavior |
| /// |
| /// On overflow, this function will panic if overflow checks are enabled (default in debug |
| /// mode) and wrap if overflow checks are disabled (default in release mode). |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| /// #![feature(int_roundings)] |
| #[doc = concat!("let a: ", stringify!($SelfT)," = 8;")] |
| /// let b = 3; |
| /// |
| /// assert_eq!(a.div_ceil(b), 3); |
| /// assert_eq!(a.div_ceil(-b), -2); |
| /// assert_eq!((-a).div_ceil(b), -2); |
| /// assert_eq!((-a).div_ceil(-b), 3); |
| /// ``` |
| #[unstable(feature = "int_roundings", issue = "88581")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[rustc_inherit_overflow_checks] |
| pub const fn div_ceil(self, rhs: Self) -> Self { |
| let d = self / rhs; |
| let r = self % rhs; |
| if (r > 0 && rhs > 0) || (r < 0 && rhs < 0) { |
| d + 1 |
| } else { |
| d |
| } |
| } |
| |
| /// If `rhs` is positive, calculates the smallest value greater than or |
| /// equal to `self` that is a multiple of `rhs`. If `rhs` is negative, |
| /// calculates the largest value less than or equal to `self` that is a |
| /// multiple of `rhs`. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `rhs` is zero. |
| /// |
| /// ## Overflow behavior |
| /// |
| /// On overflow, this function will panic if overflow checks are enabled (default in debug |
| /// mode) and wrap if overflow checks are disabled (default in release mode). |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| /// #![feature(int_roundings)] |
| #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".next_multiple_of(8), 16);")] |
| #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".next_multiple_of(8), 24);")] |
| #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".next_multiple_of(-8), 16);")] |
| #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".next_multiple_of(-8), 16);")] |
| #[doc = concat!("assert_eq!((-16_", stringify!($SelfT), ").next_multiple_of(8), -16);")] |
| #[doc = concat!("assert_eq!((-23_", stringify!($SelfT), ").next_multiple_of(8), -16);")] |
| #[doc = concat!("assert_eq!((-16_", stringify!($SelfT), ").next_multiple_of(-8), -16);")] |
| #[doc = concat!("assert_eq!((-23_", stringify!($SelfT), ").next_multiple_of(-8), -24);")] |
| /// ``` |
| #[unstable(feature = "int_roundings", issue = "88581")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[rustc_inherit_overflow_checks] |
| pub const fn next_multiple_of(self, rhs: Self) -> Self { |
| // This would otherwise fail when calculating `r` when self == T::MIN. |
| if rhs == -1 { |
| return self; |
| } |
| |
| let r = self % rhs; |
| let m = if (r > 0 && rhs < 0) || (r < 0 && rhs > 0) { |
| r + rhs |
| } else { |
| r |
| }; |
| |
| if m == 0 { |
| self |
| } else { |
| self + (rhs - m) |
| } |
| } |
| |
| /// If `rhs` is positive, calculates the smallest value greater than or |
| /// equal to `self` that is a multiple of `rhs`. If `rhs` is negative, |
| /// calculates the largest value less than or equal to `self` that is a |
| /// multiple of `rhs`. Returns `None` if `rhs` is zero or the operation |
| /// would result in overflow. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| /// #![feature(int_roundings)] |
| #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(16));")] |
| #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".checked_next_multiple_of(8), Some(24));")] |
| #[doc = concat!("assert_eq!(16_", stringify!($SelfT), ".checked_next_multiple_of(-8), Some(16));")] |
| #[doc = concat!("assert_eq!(23_", stringify!($SelfT), ".checked_next_multiple_of(-8), Some(16));")] |
| #[doc = concat!("assert_eq!((-16_", stringify!($SelfT), ").checked_next_multiple_of(8), Some(-16));")] |
| #[doc = concat!("assert_eq!((-23_", stringify!($SelfT), ").checked_next_multiple_of(8), Some(-16));")] |
| #[doc = concat!("assert_eq!((-16_", stringify!($SelfT), ").checked_next_multiple_of(-8), Some(-16));")] |
| #[doc = concat!("assert_eq!((-23_", stringify!($SelfT), ").checked_next_multiple_of(-8), Some(-24));")] |
| #[doc = concat!("assert_eq!(1_", stringify!($SelfT), ".checked_next_multiple_of(0), None);")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_next_multiple_of(2), None);")] |
| /// ``` |
| #[unstable(feature = "int_roundings", issue = "88581")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_next_multiple_of(self, rhs: Self) -> Option<Self> { |
| // This would otherwise fail when calculating `r` when self == T::MIN. |
| if rhs == -1 { |
| return Some(self); |
| } |
| |
| let r = try_opt!(self.checked_rem(rhs)); |
| let m = if (r > 0 && rhs < 0) || (r < 0 && rhs > 0) { |
| // r + rhs cannot overflow because they have opposite signs |
| r + rhs |
| } else { |
| r |
| }; |
| |
| if m == 0 { |
| Some(self) |
| } else { |
| // rhs - m cannot overflow because m has the same sign as rhs |
| self.checked_add(rhs - m) |
| } |
| } |
| |
| /// Returns the logarithm of the number with respect to an arbitrary base, |
| /// rounded down. |
| /// |
| /// This method might not be optimized owing to implementation details; |
| /// `ilog2` can produce results more efficiently for base 2, and `ilog10` |
| /// can produce results more efficiently for base 10. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `self` is less than or equal to zero, |
| /// or if `base` is less than 2. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".ilog(5), 1);")] |
| /// ``` |
| #[stable(feature = "int_log", since = "1.67.0")] |
| #[rustc_const_stable(feature = "int_log", since = "1.67.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[track_caller] |
| pub const fn ilog(self, base: Self) -> u32 { |
| assert!(base >= 2, "base of integer logarithm must be at least 2"); |
| if let Some(log) = self.checked_ilog(base) { |
| log |
| } else { |
| int_log10::panic_for_nonpositive_argument() |
| } |
| } |
| |
| /// Returns the base 2 logarithm of the number, rounded down. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `self` is less than or equal to zero. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".ilog2(), 1);")] |
| /// ``` |
| #[stable(feature = "int_log", since = "1.67.0")] |
| #[rustc_const_stable(feature = "int_log", since = "1.67.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[track_caller] |
| pub const fn ilog2(self) -> u32 { |
| if let Some(log) = self.checked_ilog2() { |
| log |
| } else { |
| int_log10::panic_for_nonpositive_argument() |
| } |
| } |
| |
| /// Returns the base 10 logarithm of the number, rounded down. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if `self` is less than or equal to zero. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".ilog10(), 1);")] |
| /// ``` |
| #[stable(feature = "int_log", since = "1.67.0")] |
| #[rustc_const_stable(feature = "int_log", since = "1.67.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[track_caller] |
| pub const fn ilog10(self) -> u32 { |
| if let Some(log) = self.checked_ilog10() { |
| log |
| } else { |
| int_log10::panic_for_nonpositive_argument() |
| } |
| } |
| |
| /// Returns the logarithm of the number with respect to an arbitrary base, |
| /// rounded down. |
| /// |
| /// Returns `None` if the number is negative or zero, or if the base is not at least 2. |
| /// |
| /// This method might not be optimized owing to implementation details; |
| /// `checked_ilog2` can produce results more efficiently for base 2, and |
| /// `checked_ilog10` can produce results more efficiently for base 10. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_ilog(5), Some(1));")] |
| /// ``` |
| #[stable(feature = "int_log", since = "1.67.0")] |
| #[rustc_const_stable(feature = "int_log", since = "1.67.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_ilog(self, base: Self) -> Option<u32> { |
| if self <= 0 || base <= 1 { |
| None |
| } else { |
| let mut n = 0; |
| let mut r = self; |
| |
| // Optimization for 128 bit wide integers. |
| if Self::BITS == 128 { |
| let b = Self::ilog2(self) / (Self::ilog2(base) + 1); |
| n += b; |
| r /= base.pow(b as u32); |
| } |
| |
| while r >= base { |
| r /= base; |
| n += 1; |
| } |
| Some(n) |
| } |
| } |
| |
| /// Returns the base 2 logarithm of the number, rounded down. |
| /// |
| /// Returns `None` if the number is negative or zero. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_ilog2(), Some(1));")] |
| /// ``` |
| #[stable(feature = "int_log", since = "1.67.0")] |
| #[rustc_const_stable(feature = "int_log", since = "1.67.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_ilog2(self) -> Option<u32> { |
| if self <= 0 { |
| None |
| } else { |
| // SAFETY: We just checked that this number is positive |
| let log = (Self::BITS - 1) - unsafe { intrinsics::ctlz_nonzero(self) as u32 }; |
| Some(log) |
| } |
| } |
| |
| /// Returns the base 10 logarithm of the number, rounded down. |
| /// |
| /// Returns `None` if the number is negative or zero. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_ilog10(), Some(1));")] |
| /// ``` |
| #[stable(feature = "int_log", since = "1.67.0")] |
| #[rustc_const_stable(feature = "int_log", since = "1.67.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_ilog10(self) -> Option<u32> { |
| if self > 0 { |
| Some(int_log10::$ActualT(self as $ActualT)) |
| } else { |
| None |
| } |
| } |
| |
| /// Computes the absolute value of `self`. |
| /// |
| /// # Overflow behavior |
| /// |
| /// The absolute value of |
| #[doc = concat!("`", stringify!($SelfT), "::MIN`")] |
| /// cannot be represented as an |
| #[doc = concat!("`", stringify!($SelfT), "`,")] |
| /// and attempting to calculate it will cause an overflow. This means |
| /// that code in debug mode will trigger a panic on this case and |
| /// optimized code will return |
| #[doc = concat!("`", stringify!($SelfT), "::MIN`")] |
| /// without a panic. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".abs(), 10);")] |
| #[doc = concat!("assert_eq!((-10", stringify!($SelfT), ").abs(), 10);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[allow(unused_attributes)] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| #[rustc_inherit_overflow_checks] |
| pub const fn abs(self) -> Self { |
| // Note that the #[rustc_inherit_overflow_checks] and #[inline] |
| // above mean that the overflow semantics of the subtraction |
| // depend on the crate we're being called from. |
| if self.is_negative() { |
| -self |
| } else { |
| self |
| } |
| } |
| |
| /// 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: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(80), 20", stringify!($UnsignedT), ");")] |
| #[doc = concat!("assert_eq!(100", stringify!($SelfT), ".abs_diff(110), 10", stringify!($UnsignedT), ");")] |
| #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").abs_diff(80), 180", stringify!($UnsignedT), ");")] |
| #[doc = concat!("assert_eq!((-100", stringify!($SelfT), ").abs_diff(-120), 20", stringify!($UnsignedT), ");")] |
| #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.abs_diff(", stringify!($SelfT), "::MAX), ", stringify!($UnsignedT), "::MAX);")] |
| /// ``` |
| #[stable(feature = "int_abs_diff", since = "1.60.0")] |
| #[rustc_const_stable(feature = "int_abs_diff", since = "1.60.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn abs_diff(self, other: Self) -> $UnsignedT { |
| if self < other { |
| // Converting a non-negative x from signed to unsigned by using |
| // `x as U` is left unchanged, but a negative x is converted |
| // to value x + 2^N. Thus if `s` and `o` are binary variables |
| // respectively indicating whether `self` and `other` are |
| // negative, we are computing the mathematical value: |
| // |
| // (other + o*2^N) - (self + s*2^N) mod 2^N |
| // other - self + (o-s)*2^N mod 2^N |
| // other - self mod 2^N |
| // |
| // Finally, taking the mod 2^N of the mathematical value of |
| // `other - self` does not change it as it already is |
| // in the range [0, 2^N). |
| (other as $UnsignedT).wrapping_sub(self as $UnsignedT) |
| } else { |
| (self as $UnsignedT).wrapping_sub(other as $UnsignedT) |
| } |
| } |
| |
| /// Returns a number representing sign of `self`. |
| /// |
| /// - `0` if the number is zero |
| /// - `1` if the number is positive |
| /// - `-1` if the number is negative |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".signum(), 1);")] |
| #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".signum(), 0);")] |
| #[doc = concat!("assert_eq!((-10", stringify!($SelfT), ").signum(), -1);")] |
| /// ``` |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_sign", since = "1.47.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline(always)] |
| #[rustc_allow_const_fn_unstable(const_cmp)] |
| pub const fn signum(self) -> Self { |
| // Picking the right way to phrase this is complicated |
| // (<https://graphics.stanford.edu/~seander/bithacks.html#CopyIntegerSign>) |
| // so delegate it to `Ord` which is already producing -1/0/+1 |
| // exactly like we need and can be the place to deal with the complexity. |
| self.cmp(&0) as _ |
| } |
| |
| /// Returns `true` if `self` is positive and `false` if the number is zero or |
| /// negative. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert!(10", stringify!($SelfT), ".is_positive());")] |
| #[doc = concat!("assert!(!(-10", stringify!($SelfT), ").is_positive());")] |
| /// ``` |
| #[must_use] |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[inline(always)] |
| pub const fn is_positive(self) -> bool { self > 0 } |
| |
| /// Returns `true` if `self` is negative and `false` if the number is zero or |
| /// positive. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("assert!((-10", stringify!($SelfT), ").is_negative());")] |
| #[doc = concat!("assert!(!10", stringify!($SelfT), ".is_negative());")] |
| /// ``` |
| #[must_use] |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] |
| #[inline(always)] |
| pub const fn is_negative(self) -> bool { self < 0 } |
| |
| /// Return the memory representation of this integer as a byte array in |
| /// big-endian (network) byte order. |
| /// |
| #[doc = $to_xe_bytes_doc] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_be_bytes();")] |
| #[doc = concat!("assert_eq!(bytes, ", $be_bytes, ");")] |
| /// ``` |
| #[stable(feature = "int_to_from_bytes", since = "1.32.0")] |
| #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn to_be_bytes(self) -> [u8; mem::size_of::<Self>()] { |
| self.to_be().to_ne_bytes() |
| } |
| |
| /// Return the memory representation of this integer as a byte array in |
| /// little-endian byte order. |
| /// |
| #[doc = $to_xe_bytes_doc] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_le_bytes();")] |
| #[doc = concat!("assert_eq!(bytes, ", $le_bytes, ");")] |
| /// ``` |
| #[stable(feature = "int_to_from_bytes", since = "1.32.0")] |
| #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn to_le_bytes(self) -> [u8; mem::size_of::<Self>()] { |
| self.to_le().to_ne_bytes() |
| } |
| |
| /// 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. |
| /// |
| #[doc = $to_xe_bytes_doc] |
| /// |
| /// [`to_be_bytes`]: Self::to_be_bytes |
| /// [`to_le_bytes`]: Self::to_le_bytes |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("let bytes = ", $swap_op, stringify!($SelfT), ".to_ne_bytes();")] |
| /// assert_eq!( |
| /// bytes, |
| /// if cfg!(target_endian = "big") { |
| #[doc = concat!(" ", $be_bytes)] |
| /// } else { |
| #[doc = concat!(" ", $le_bytes)] |
| /// } |
| /// ); |
| /// ``` |
| #[stable(feature = "int_to_from_bytes", since = "1.32.0")] |
| #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")] |
| // SAFETY: const sound because integers are plain old datatypes so we can always |
| // transmute them to arrays of bytes |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn to_ne_bytes(self) -> [u8; mem::size_of::<Self>()] { |
| // SAFETY: integers are plain old datatypes so we can always transmute them to |
| // arrays of bytes |
| unsafe { mem::transmute(self) } |
| } |
| |
| /// Create an integer value from its representation as a byte array in |
| /// big endian. |
| /// |
| #[doc = $from_xe_bytes_doc] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("let value = ", stringify!($SelfT), "::from_be_bytes(", $be_bytes, ");")] |
| #[doc = concat!("assert_eq!(value, ", $swap_op, ");")] |
| /// ``` |
| /// |
| /// When starting from a slice rather than an array, fallible conversion APIs can be used: |
| /// |
| /// ``` |
| #[doc = concat!("fn read_be_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")] |
| #[doc = concat!(" let (int_bytes, rest) = input.split_at(std::mem::size_of::<", stringify!($SelfT), ">());")] |
| /// *input = rest; |
| #[doc = concat!(" ", stringify!($SelfT), "::from_be_bytes(int_bytes.try_into().unwrap())")] |
| /// } |
| /// ``` |
| #[stable(feature = "int_to_from_bytes", since = "1.32.0")] |
| #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")] |
| #[must_use] |
| #[inline] |
| pub const fn from_be_bytes(bytes: [u8; mem::size_of::<Self>()]) -> Self { |
| Self::from_be(Self::from_ne_bytes(bytes)) |
| } |
| |
| /// Create an integer value from its representation as a byte array in |
| /// little endian. |
| /// |
| #[doc = $from_xe_bytes_doc] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("let value = ", stringify!($SelfT), "::from_le_bytes(", $le_bytes, ");")] |
| #[doc = concat!("assert_eq!(value, ", $swap_op, ");")] |
| /// ``` |
| /// |
| /// When starting from a slice rather than an array, fallible conversion APIs can be used: |
| /// |
| /// ``` |
| #[doc = concat!("fn read_le_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")] |
| #[doc = concat!(" let (int_bytes, rest) = input.split_at(std::mem::size_of::<", stringify!($SelfT), ">());")] |
| /// *input = rest; |
| #[doc = concat!(" ", stringify!($SelfT), "::from_le_bytes(int_bytes.try_into().unwrap())")] |
| /// } |
| /// ``` |
| #[stable(feature = "int_to_from_bytes", since = "1.32.0")] |
| #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")] |
| #[must_use] |
| #[inline] |
| pub const fn from_le_bytes(bytes: [u8; mem::size_of::<Self>()]) -> Self { |
| Self::from_le(Self::from_ne_bytes(bytes)) |
| } |
| |
| /// 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. |
| /// |
| /// [`from_be_bytes`]: Self::from_be_bytes |
| /// [`from_le_bytes`]: Self::from_le_bytes |
| /// |
| #[doc = $from_xe_bytes_doc] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("let value = ", stringify!($SelfT), "::from_ne_bytes(if cfg!(target_endian = \"big\") {")] |
| #[doc = concat!(" ", $be_bytes)] |
| /// } else { |
| #[doc = concat!(" ", $le_bytes)] |
| /// }); |
| #[doc = concat!("assert_eq!(value, ", $swap_op, ");")] |
| /// ``` |
| /// |
| /// When starting from a slice rather than an array, fallible conversion APIs can be used: |
| /// |
| /// ``` |
| #[doc = concat!("fn read_ne_", stringify!($SelfT), "(input: &mut &[u8]) -> ", stringify!($SelfT), " {")] |
| #[doc = concat!(" let (int_bytes, rest) = input.split_at(std::mem::size_of::<", stringify!($SelfT), ">());")] |
| /// *input = rest; |
| #[doc = concat!(" ", stringify!($SelfT), "::from_ne_bytes(int_bytes.try_into().unwrap())")] |
| /// } |
| /// ``` |
| #[stable(feature = "int_to_from_bytes", since = "1.32.0")] |
| #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")] |
| #[must_use] |
| // SAFETY: const sound because integers are plain old datatypes so we can always |
| // transmute to them |
| #[inline] |
| pub const fn from_ne_bytes(bytes: [u8; mem::size_of::<Self>()]) -> Self { |
| // SAFETY: integers are plain old datatypes so we can always transmute to them |
| unsafe { mem::transmute(bytes) } |
| } |
| |
| /// New code should prefer to use |
| #[doc = concat!("[`", stringify!($SelfT), "::MIN", "`] instead.")] |
| /// |
| /// Returns the smallest value that can be represented by this integer type. |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[inline(always)] |
| #[rustc_promotable] |
| #[rustc_const_stable(feature = "const_min_value", since = "1.32.0")] |
| #[deprecated(since = "TBD", note = "replaced by the `MIN` associated constant on this type")] |
| pub const fn min_value() -> Self { |
| Self::MIN |
| } |
| |
| /// New code should prefer to use |
| #[doc = concat!("[`", stringify!($SelfT), "::MAX", "`] instead.")] |
| /// |
| /// Returns the largest value that can be represented by this integer type. |
| #[stable(feature = "rust1", since = "1.0.0")] |
| #[inline(always)] |
| #[rustc_promotable] |
| #[rustc_const_stable(feature = "const_max_value", since = "1.32.0")] |
| #[deprecated(since = "TBD", note = "replaced by the `MAX` associated constant on this type")] |
| pub const fn max_value() -> Self { |
| Self::MAX |
| } |
| } |
| } |