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", $BITS_MINUS_ONE, "", $bound_condition, ").")] /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(", stringify!($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", $BITS_MINUS_ONE, " − 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 = <$UnsignedT>::BITS; /// Returns the number of ones in the binary representation of `self`. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("let n = 0b100_0000", stringify!($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 $UnsignedT).trailing_ones() } /// Returns the bit pattern of `self` reinterpreted as an unsigned integer of the same size. /// /// This produces the same result as an `as` cast, but ensures that the bit-width remains /// the same. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(integer_sign_cast)] /// #[doc = concat!("let n = -1", stringify!($SelfT), ";")] /// #[doc = concat!("assert_eq!(n.cast_unsigned(), ", stringify!($UnsignedT), "::MAX);")] /// ``` #[unstable(feature = "integer_sign_cast", issue = "125882")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline(always)] pub const fn cast_unsigned(self) -> $UnsignedT { self as $UnsignedT } /// 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 { let (a, b) = self.overflowing_add(rhs); if intrinsics::unlikely(b) { None } else { Some(a) } } /// Strict integer addition. Computes `self + rhs`, panicking /// if overflow occurred. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MAX - 2).strict_add(1), ", stringify!($SelfT), "::MAX - 1);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add(3);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_add(self, rhs: Self) -> Self { let (a, b) = self.overflowing_add(rhs); if b { overflow_panic::add() } else { a } } /// Unchecked integer addition. Computes `self + rhs`, assuming overflow /// cannot occur. /// /// Calling `x.unchecked_add(y)` is semantically equivalent to calling /// `x.`[`checked_add`]`(y).`[`unwrap_unchecked`]`()`. /// /// If you're just trying to avoid the panic in debug mode, then **do not** /// use this. Instead, you're looking for [`wrapping_add`]. /// /// # Safety /// /// This results in undefined behavior when #[doc = concat!("`self + rhs > ", stringify!($SelfT), "::MAX` or `self + rhs < ", stringify!($SelfT), "::MIN`,")] /// i.e. when [`checked_add`] would return `None`. /// /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked #[doc = concat!("[`checked_add`]: ", stringify!($SelfT), "::checked_add")] #[doc = concat!("[`wrapping_add`]: ", stringify!($SelfT), "::wrapping_add")] #[stable(feature = "unchecked_math", since = "1.79.0")] #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn unchecked_add(self, rhs: Self) -> Self { assert_unsafe_precondition!( check_language_ub, concat!(stringify!($SelfT), "::unchecked_add cannot overflow"), ( lhs: $SelfT = self, rhs: $SelfT = rhs, ) => !lhs.overflowing_add(rhs).1, ); // SAFETY: this is guaranteed to be safe by the caller. unsafe { intrinsics::unchecked_add(self, rhs) } } /// Checked addition with an unsigned integer. Computes `self + rhs`, /// returning `None` if overflow occurred. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(1", stringify!($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: $UnsignedT) -> Option { let (a, b) = self.overflowing_add_unsigned(rhs); if intrinsics::unlikely(b) { None } else { Some(a) } } /// Strict addition with an unsigned integer. Computes `self + rhs`, /// panicking if overflow occurred. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_add_unsigned(2), 3);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = (", stringify!($SelfT), "::MAX - 2).strict_add_unsigned(3);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_add_unsigned(self, rhs: $UnsignedT) -> Self { let (a, b) = self.overflowing_add_unsigned(rhs); if b { overflow_panic::add() } else { a } } /// Checked integer subtraction. Computes `self - rhs`, returning `None` if /// overflow occurred. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!((", stringify!($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 { let (a, b) = self.overflowing_sub(rhs); if intrinsics::unlikely(b) { None } else { Some(a) } } /// Strict integer subtraction. Computes `self - rhs`, panicking if /// overflow occurred. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 2).strict_sub(1), ", stringify!($SelfT), "::MIN + 1);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = (", stringify!($SelfT), "::MIN + 2).strict_sub(3);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_sub(self, rhs: Self) -> Self { let (a, b) = self.overflowing_sub(rhs); if b { overflow_panic::sub() } else { a } } /// Unchecked integer subtraction. Computes `self - rhs`, assuming overflow /// cannot occur. /// /// Calling `x.unchecked_sub(y)` is semantically equivalent to calling /// `x.`[`checked_sub`]`(y).`[`unwrap_unchecked`]`()`. /// /// If you're just trying to avoid the panic in debug mode, then **do not** /// use this. Instead, you're looking for [`wrapping_sub`]. /// /// # Safety /// /// This results in undefined behavior when #[doc = concat!("`self - rhs > ", stringify!($SelfT), "::MAX` or `self - rhs < ", stringify!($SelfT), "::MIN`,")] /// i.e. when [`checked_sub`] would return `None`. /// /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked #[doc = concat!("[`checked_sub`]: ", stringify!($SelfT), "::checked_sub")] #[doc = concat!("[`wrapping_sub`]: ", stringify!($SelfT), "::wrapping_sub")] #[stable(feature = "unchecked_math", since = "1.79.0")] #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn unchecked_sub(self, rhs: Self) -> Self { assert_unsafe_precondition!( check_language_ub, concat!(stringify!($SelfT), "::unchecked_sub cannot overflow"), ( lhs: $SelfT = self, rhs: $SelfT = rhs, ) => !lhs.overflowing_sub(rhs).1, ); // SAFETY: this is guaranteed to be safe by the caller. unsafe { intrinsics::unchecked_sub(self, rhs) } } /// Checked subtraction with an unsigned integer. Computes `self - rhs`, /// returning `None` if overflow occurred. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(1", stringify!($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: $UnsignedT) -> Option { let (a, b) = self.overflowing_sub_unsigned(rhs); if intrinsics::unlikely(b) { None } else { Some(a) } } /// Strict subtraction with an unsigned integer. Computes `self - rhs`, /// panicking if overflow occurred. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".strict_sub_unsigned(2), -1);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = (", stringify!($SelfT), "::MIN + 2).strict_sub_unsigned(3);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_sub_unsigned(self, rhs: $UnsignedT) -> Self { let (a, b) = self.overflowing_sub_unsigned(rhs); if b { overflow_panic::sub() } else { a } } /// Checked integer multiplication. Computes `self * rhs`, returning `None` if /// overflow occurred. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(", stringify!($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 { let (a, b) = self.overflowing_mul(rhs); if intrinsics::unlikely(b) { None } else { Some(a) } } /// Strict integer multiplication. Computes `self * rhs`, panicking if /// overflow occurred. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.strict_mul(1), ", stringify!($SelfT), "::MAX);")] /// ``` /// /// The following panics because of overflow: /// /// ``` should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_mul(2);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_mul(self, rhs: Self) -> Self { let (a, b) = self.overflowing_mul(rhs); if b { overflow_panic::mul() } else { a } } /// Unchecked integer multiplication. Computes `self * rhs`, assuming overflow /// cannot occur. /// /// Calling `x.unchecked_mul(y)` is semantically equivalent to calling /// `x.`[`checked_mul`]`(y).`[`unwrap_unchecked`]`()`. /// /// If you're just trying to avoid the panic in debug mode, then **do not** /// use this. Instead, you're looking for [`wrapping_mul`]. /// /// # Safety /// /// This results in undefined behavior when #[doc = concat!("`self * rhs > ", stringify!($SelfT), "::MAX` or `self * rhs < ", stringify!($SelfT), "::MIN`,")] /// i.e. when [`checked_mul`] would return `None`. /// /// [`unwrap_unchecked`]: option/enum.Option.html#method.unwrap_unchecked #[doc = concat!("[`checked_mul`]: ", stringify!($SelfT), "::checked_mul")] #[doc = concat!("[`wrapping_mul`]: ", stringify!($SelfT), "::wrapping_mul")] #[stable(feature = "unchecked_math", since = "1.79.0")] #[rustc_const_stable(feature = "unchecked_math", since = "1.79.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn unchecked_mul(self, rhs: Self) -> Self { assert_unsafe_precondition!( check_language_ub, concat!(stringify!($SelfT), "::unchecked_mul cannot overflow"), ( lhs: $SelfT = self, rhs: $SelfT = rhs, ) => !lhs.overflowing_mul(rhs).1, ); // SAFETY: this is guaranteed to be safe by the caller. unsafe { intrinsics::unchecked_mul(self, rhs) } } /// Checked integer division. Computes `self / rhs`, returning `None` if `rhs == 0` /// or the division results in overflow. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!((", stringify!($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!($SelfT), ").checked_div(0), None);")] /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "const_checked_int_div", since = "1.52.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn checked_div(self, rhs: Self) -> Option { if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) && (rhs == -1))) { None } else { // SAFETY: div by zero and by INT_MIN have been checked above Some(unsafe { intrinsics::unchecked_div(self, rhs) }) } } /// Strict integer division. Computes `self / rhs`, panicking /// if overflow occurred. /// /// # Panics /// /// This function will panic if `rhs` is zero. /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// The only case where such an overflow can occur is when one divides `MIN / -1` on a signed type (where /// `MIN` is the negative minimal value for the type); this is equivalent to `-MIN`, a positive value /// that is too large to represent in the type. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).strict_div(-1), ", stringify!($Max), ");")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_div(-1);")] /// ``` /// /// The following panics because of division by zero: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div(0);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_div(self, rhs: Self) -> Self { let (a, b) = self.overflowing_div(rhs); if b { overflow_panic::div() } else { a } } /// Checked Euclidean division. Computes `self.div_euclid(rhs)`, /// returning `None` if `rhs == 0` or the division results in overflow. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!((", stringify!($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!($SelfT), ").checked_div_euclid(0), None);")] /// ``` #[stable(feature = "euclidean_division", since = "1.38.0")] #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn checked_div_euclid(self, rhs: Self) -> Option { // Using `&` helps LLVM see that it is the same check made in division. if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) & (rhs == -1))) { None } else { Some(self.div_euclid(rhs)) } } /// Strict Euclidean division. Computes `self.div_euclid(rhs)`, panicking /// if overflow occurred. /// /// # Panics /// /// This function will panic if `rhs` is zero. /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// The only case where such an overflow can occur is when one divides `MIN / -1` on a signed type (where /// `MIN` is the negative minimal value for the type); this is equivalent to `-MIN`, a positive value /// that is too large to represent in the type. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!((", stringify!($SelfT), "::MIN + 1).strict_div_euclid(-1), ", stringify!($Max), ");")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_div_euclid(-1);")] /// ``` /// /// The following panics because of division by zero: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = (1", stringify!($SelfT), ").strict_div_euclid(0);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_div_euclid(self, rhs: Self) -> Self { let (a, b) = self.overflowing_div_euclid(rhs); if b { overflow_panic::div() } else { a } } /// Checked integer remainder. Computes `self % rhs`, returning `None` if /// `rhs == 0` or the division results in overflow. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(5", stringify!($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 { if intrinsics::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) }) } } /// Strict integer remainder. Computes `self % rhs`, panicking if /// the division results in overflow. /// /// # Panics /// /// This function will panic if `rhs` is zero. /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// The only case where such an overflow can occur is `x % y` for `MIN / -1` on a /// signed type (where `MIN` is the negative minimal value), which is invalid due to implementation artifacts. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".strict_rem(2), 1);")] /// ``` /// /// The following panics because of division by zero: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem(0);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_rem(-1);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_rem(self, rhs: Self) -> Self { let (a, b) = self.overflowing_rem(rhs); if b { overflow_panic::rem() } else { a } } /// Checked Euclidean remainder. Computes `self.rem_euclid(rhs)`, returning `None` /// if `rhs == 0` or the division results in overflow. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(5", stringify!($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 { // Using `&` helps LLVM see that it is the same check made in division. if intrinsics::unlikely(rhs == 0 || ((self == Self::MIN) & (rhs == -1))) { None } else { Some(self.rem_euclid(rhs)) } } /// Strict Euclidean remainder. Computes `self.rem_euclid(rhs)`, panicking if /// the division results in overflow. /// /// # Panics /// /// This function will panic if `rhs` is zero. /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// The only case where such an overflow can occur is `x % y` for `MIN / -1` on a /// signed type (where `MIN` is the negative minimal value), which is invalid due to implementation artifacts. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".strict_rem_euclid(2), 1);")] /// ``` /// /// The following panics because of division by zero: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = 5", stringify!($SelfT), ".strict_rem_euclid(0);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_rem_euclid(-1);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_rem_euclid(self, rhs: Self) -> Self { let (a, b) = self.overflowing_rem_euclid(rhs); if b { overflow_panic::rem() } else { a } } /// Checked negation. Computes `-self`, returning `None` if `self == MIN`. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_neg(), Some(-5));")] #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_neg(), None);")] /// ``` #[stable(feature = "wrapping", since = "1.7.0")] #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn checked_neg(self) -> Option { let (a, b) = self.overflowing_neg(); if intrinsics::unlikely(b) { None } else { Some(a) } } /// Unchecked negation. Computes `-self`, assuming overflow cannot occur. /// /// # Safety /// /// This results in undefined behavior when #[doc = concat!("`self == ", stringify!($SelfT), "::MIN`,")] /// i.e. when [`checked_neg`] would return `None`. /// #[doc = concat!("[`checked_neg`]: ", stringify!($SelfT), "::checked_neg")] #[unstable( feature = "unchecked_neg", reason = "niche optimization path", issue = "85122", )] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[cfg_attr(bootstrap, rustc_const_unstable(feature = "unchecked_neg", issue = "85122"))] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn unchecked_neg(self) -> Self { assert_unsafe_precondition!( check_language_ub, concat!(stringify!($SelfT), "::unchecked_neg cannot overflow"), ( lhs: $SelfT = self, ) => !lhs.overflowing_neg().1, ); // SAFETY: this is guaranteed to be safe by the caller. unsafe { intrinsics::unchecked_sub(0, self) } } /// Strict negation. Computes `-self`, panicking if `self == MIN`. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".strict_neg(), -5);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_neg();")] /// #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_neg(self) -> Self { let (a, b) = self.overflowing_neg(); if b { overflow_panic::neg() } else { a } } /// Checked shift left. Computes `self << rhs`, returning `None` if `rhs` is larger /// than or equal to the number of bits in `self`. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".checked_shl(4), Some(0x10));")] #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".checked_shl(129), None);")] #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shl(", stringify!($BITS_MINUS_ONE), "), Some(0));")] /// ``` #[stable(feature = "wrapping", since = "1.7.0")] #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] #[cfg_attr(bootstrap, rustc_allow_const_fn_unstable(unchecked_shifts))] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn checked_shl(self, rhs: u32) -> Option { // Not using overflowing_shl as that's a wrapping shift if rhs < Self::BITS { // SAFETY: just checked the RHS is in-range Some(unsafe { self.unchecked_shl(rhs) }) } else { None } } /// Strict shift left. Computes `self << rhs`, panicking if `rhs` is larger /// than or equal to the number of bits in `self`. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".strict_shl(4), 0x10);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = 0x1", stringify!($SelfT), ".strict_shl(129);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_shl(self, rhs: u32) -> Self { let (a, b) = self.overflowing_shl(rhs); if b { overflow_panic::shl() } else { a } } /// Unchecked shift left. Computes `self << rhs`, assuming that /// `rhs` is less than the number of bits in `self`. /// /// # Safety /// /// This results in undefined behavior if `rhs` is larger than /// or equal to the number of bits in `self`, /// i.e. when [`checked_shl`] would return `None`. /// #[doc = concat!("[`checked_shl`]: ", stringify!($SelfT), "::checked_shl")] #[unstable( feature = "unchecked_shifts", reason = "niche optimization path", issue = "85122", )] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[cfg_attr(bootstrap, rustc_const_unstable(feature = "unchecked_shifts", 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 { assert_unsafe_precondition!( check_language_ub, concat!(stringify!($SelfT), "::unchecked_shl cannot overflow"), ( rhs: u32 = rhs, ) => rhs < <$ActualT>::BITS, ); // SAFETY: this is guaranteed to be safe by the caller. unsafe { intrinsics::unchecked_shl(self, rhs) } } /// Unbounded shift left. Computes `self << rhs`, without bounding the value of `rhs` /// /// If `rhs` is larger or equal to the number of bits in `self`, /// the entire value is shifted out, and `0` is returned. /// /// # Examples /// /// Basic usage: /// ``` /// #![feature(unbounded_shifts)] #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(4), 0x10);")] #[doc = concat!("assert_eq!(0x1", stringify!($SelfT), ".unbounded_shl(129), 0);")] /// ``` #[unstable(feature = "unbounded_shifts", issue = "129375")] #[rustc_const_unstable(feature = "const_unbounded_shifts", issue = "129375")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn unbounded_shl(self, rhs: u32) -> $SelfT{ if rhs < Self::BITS { // SAFETY: // rhs is just checked to be in-range above unsafe { self.unchecked_shl(rhs) } } else { 0 } } /// Checked shift right. Computes `self >> rhs`, returning `None` if `rhs` is /// larger than or equal to the number of bits in `self`. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(4), Some(0x1));")] #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".checked_shr(128), None);")] /// ``` #[stable(feature = "wrapping", since = "1.7.0")] #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] #[cfg_attr(bootstrap, rustc_allow_const_fn_unstable(unchecked_shifts))] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn checked_shr(self, rhs: u32) -> Option { // Not using overflowing_shr as that's a wrapping shift if rhs < Self::BITS { // SAFETY: just checked the RHS is in-range Some(unsafe { self.unchecked_shr(rhs) }) } else { None } } /// Strict shift right. Computes `self >> rhs`, panicking `rhs` is /// larger than or equal to the number of bits in `self`. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".strict_shr(4), 0x1);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = 0x10", stringify!($SelfT), ".strict_shr(128);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_shr(self, rhs: u32) -> Self { let (a, b) = self.overflowing_shr(rhs); if b { overflow_panic::shr() } else { a } } /// Unchecked shift right. Computes `self >> rhs`, assuming that /// `rhs` is less than the number of bits in `self`. /// /// # Safety /// /// This results in undefined behavior if `rhs` is larger than /// or equal to the number of bits in `self`, /// i.e. when [`checked_shr`] would return `None`. /// #[doc = concat!("[`checked_shr`]: ", stringify!($SelfT), "::checked_shr")] #[unstable( feature = "unchecked_shifts", reason = "niche optimization path", issue = "85122", )] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[cfg_attr(bootstrap, rustc_const_unstable(feature = "unchecked_shifts", 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 { assert_unsafe_precondition!( check_language_ub, concat!(stringify!($SelfT), "::unchecked_shr cannot overflow"), ( rhs: u32 = rhs, ) => rhs < <$ActualT>::BITS, ); // SAFETY: this is guaranteed to be safe by the caller. unsafe { intrinsics::unchecked_shr(self, rhs) } } /// Unbounded shift right. Computes `self >> rhs`, without bounding the value of `rhs` /// /// If `rhs` is larger or equal to the number of bits in `self`, /// the entire value is shifted out, which yields `0` for a positive number, /// and `-1` for a negative number. /// /// # Examples /// /// Basic usage: /// ``` /// #![feature(unbounded_shifts)] #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(4), 0x1);")] #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".unbounded_shr(129), 0);")] #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.unbounded_shr(129), -1);")] /// ``` #[unstable(feature = "unbounded_shifts", issue = "129375")] #[rustc_const_unstable(feature = "const_unbounded_shifts", issue = "129375")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn unbounded_shr(self, rhs: u32) -> $SelfT{ if rhs < Self::BITS { // SAFETY: // rhs is just checked to be in-range above unsafe { self.unchecked_shr(rhs) } } else { // A shift by `Self::BITS-1` suffices for signed integers, because the sign bit is copied for each of the shifted bits. // SAFETY: // `Self::BITS-1` is guaranteed to be less than `Self::BITS` unsafe { self.unchecked_shr(Self::BITS - 1) } } } /// Checked absolute value. Computes `self.abs()`, returning `None` if /// `self == MIN`. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!((-5", stringify!($SelfT), ").checked_abs(), Some(5));")] #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.checked_abs(), None);")] /// ``` #[stable(feature = "no_panic_abs", since = "1.13.0")] #[rustc_const_stable(feature = "const_checked_int_methods", since = "1.47.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn checked_abs(self) -> Option { if self.is_negative() { self.checked_neg() } else { Some(self) } } /// Strict absolute value. Computes `self.abs()`, panicking if /// `self == MIN`. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!((-5", stringify!($SelfT), ").strict_abs(), 5);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.strict_abs();")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_abs(self) -> Self { if self.is_negative() { self.strict_neg() } else { self } } /// Checked exponentiation. Computes `self.pow(exp)`, returning `None` if /// overflow occurred. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(8", stringify!($SelfT), ".checked_pow(2), Some(64));")] #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.checked_pow(2), None);")] /// ``` #[stable(feature = "no_panic_pow", since = "1.34.0")] #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn checked_pow(self, mut exp: u32) -> Option { if exp == 0 { return Some(1); } let mut base = self; let mut acc: Self = 1; loop { if (exp & 1) == 1 { acc = try_opt!(acc.checked_mul(base)); // since exp!=0, finally the exp must be 1. if exp == 1 { return Some(acc); } } exp /= 2; base = try_opt!(base.checked_mul(base)); } } /// Strict exponentiation. Computes `self.pow(exp)`, panicking if /// overflow occurred. /// /// # Panics /// /// ## Overflow behavior /// /// This function will always panic on overflow, regardless of whether overflow checks are enabled. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(strict_overflow_ops)] #[doc = concat!("assert_eq!(8", stringify!($SelfT), ".strict_pow(2), 64);")] /// ``` /// /// The following panics because of overflow: /// /// ```should_panic /// #![feature(strict_overflow_ops)] #[doc = concat!("let _ = ", stringify!($SelfT), "::MAX.strict_pow(2);")] /// ``` #[unstable(feature = "strict_overflow_ops", issue = "118260")] #[rustc_const_unstable(feature = "const_strict_overflow_ops", issue = "118260")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn strict_pow(self, mut exp: u32) -> Self { if exp == 0 { return 1; } let mut base = self; let mut acc: Self = 1; loop { if (exp & 1) == 1 { acc = acc.strict_mul(base); // since exp!=0, finally the exp must be 1. if exp == 1 { return acc; } } exp /= 2; base = base.strict_mul(base); } } /// Returns the square root of the number, rounded down. /// /// Returns `None` if `self` is negative. /// /// # Examples /// /// Basic usage: /// ``` #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_isqrt(), Some(3));")] /// ``` #[stable(feature = "isqrt", since = "CURRENT_RUSTC_VERSION")] #[rustc_const_stable(feature = "isqrt", since = "CURRENT_RUSTC_VERSION")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn checked_isqrt(self) -> Option { if self < 0 { None } else { // SAFETY: Input is nonnegative in this `else` branch. let result = unsafe { crate::num::int_sqrt::$ActualT(self as $ActualT) as $SelfT }; // Inform the optimizer what the range of outputs is. If // testing `core` crashes with no panic message and a // `num::int_sqrt::i*` test failed, it's because your edits // caused these assertions to become false. // // SAFETY: Integer square root is a monotonically nondecreasing // function, which means that increasing the input will never // cause the output to decrease. Thus, since the input for // nonnegative signed integers is bounded by // `[0, <$ActualT>::MAX]`, sqrt(n) will be bounded by // `[sqrt(0), sqrt(<$ActualT>::MAX)]`. unsafe { // SAFETY: `<$ActualT>::MAX` is nonnegative. const MAX_RESULT: $SelfT = unsafe { crate::num::int_sqrt::$ActualT(<$ActualT>::MAX) as $SelfT }; crate::hint::assert_unchecked(result >= 0); crate::hint::assert_unchecked(result <= MAX_RESULT); } Some(result) } } /// Saturating integer addition. Computes `self + rhs`, saturating at the numeric /// bounds instead of overflowing. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(100", stringify!($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. /// /// # Panics /// /// This function will panic if `rhs` is 0. /// /// # 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!($SelfT), "::MAX);")] /// /// ``` #[stable(feature = "saturating_div", since = "1.58.0")] #[rustc_const_stable(feature = "saturating_div", since = "1.58.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn saturating_div(self, rhs: Self) -> Self { match self.overflowing_div(rhs) { (result, false) => result, (_result, true) => Self::MAX, // MIN / -1 is the only possible saturating overflow } } /// Saturating integer exponentiation. Computes `self.pow(exp)`, /// saturating at the numeric bounds instead of overflowing. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!((-4", stringify!($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!($SelfT), ").wrapping_shl(128), -1);")] /// ``` #[stable(feature = "num_wrapping", since = "1.2.0")] #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline(always)] #[cfg_attr(bootstrap, rustc_allow_const_fn_unstable(unchecked_shifts))] pub const fn wrapping_shl(self, rhs: u32) -> Self { // SAFETY: the masking by the bitsize of the type ensures that we do not shift // out of bounds unsafe { self.unchecked_shl(rhs & (Self::BITS - 1)) } } /// Panic-free bitwise shift-right; yields `self >> mask(rhs)`, where `mask` /// removes any high-order bits of `rhs` that would cause the shift to exceed the bitwidth of the type. /// /// Note that this is *not* the same as a rotate-right; the RHS of a wrapping shift-right is restricted /// to the range of the type, rather than the bits shifted out of the LHS being returned to the other /// end. The primitive integer types all implement a [`rotate_right`](Self::rotate_right) function, /// which may be what you want instead. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!((-128", stringify!($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)] #[cfg_attr(bootstrap, rustc_allow_const_fn_unstable(unchecked_shifts))] 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] #[rustc_allow_const_fn_unstable(is_val_statically_known)] pub const fn wrapping_pow(self, mut exp: u32) -> Self { if exp == 0 { return 1; } let mut base = self; let mut acc: Self = 1; if intrinsics::is_val_statically_known(exp) { 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. acc.wrapping_mul(base) } else { // This is faster than the above when the exponent is not known // at compile time. We can't use the same code for the constant // exponent case because LLVM is currently unable to unroll // this loop. loop { if (exp & 1) == 1 { acc = acc.wrapping_mul(base); // since exp!=0, finally the exp must be 1. if exp == 1 { return acc; } } exp /= 2; base = base.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 intrinsics::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!($SelfT), "::MIN, true));")] /// ``` #[inline] #[stable(feature = "euclidean_division", since = "1.38.0")] #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] pub const fn overflowing_div_euclid(self, rhs: Self) -> (Self, bool) { // Using `&` helps LLVM see that it is the same check made in division. if intrinsics::unlikely((self == Self::MIN) & (rhs == -1)) { (self, true) } else { (self.div_euclid(rhs), false) } } /// Calculates the remainder when `self` is divided by `rhs`. /// /// Returns a tuple of the remainder after dividing along with a boolean indicating whether an /// arithmetic overflow would occur. If an overflow would occur then 0 is returned. /// /// # Panics /// /// This function will panic if `rhs` is 0. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem(2), (1, false));")] #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_rem(-1), (0, true));")] /// ``` #[inline] #[stable(feature = "wrapping", since = "1.7.0")] #[rustc_const_stable(feature = "const_overflowing_int_methods", since = "1.52.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] pub const fn overflowing_rem(self, rhs: Self) -> (Self, bool) { if intrinsics::unlikely(rhs == -1) { (0, self == Self::MIN) } else { (self % rhs, false) } } /// Overflowing Euclidean remainder. Calculates `self.rem_euclid(rhs)`. /// /// Returns a tuple of the remainder after dividing along with a boolean indicating whether an /// arithmetic overflow would occur. If an overflow would occur then 0 is returned. /// /// # Panics /// /// This function will panic if `rhs` is 0. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".overflowing_rem_euclid(2), (1, false));")] #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.overflowing_rem_euclid(-1), (0, true));")] /// ``` #[stable(feature = "euclidean_division", since = "1.38.0")] #[rustc_const_stable(feature = "const_euclidean_int_methods", since = "1.52.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn overflowing_rem_euclid(self, rhs: Self) -> (Self, bool) { if intrinsics::unlikely(rhs == -1) { (0, self == Self::MIN) } else { (self.rem_euclid(rhs), false) } } /// Negates self, overflowing if this is equal to the minimum value. /// /// Returns a tuple of the negated version of self along with a boolean indicating whether an overflow /// happened. If `self` is the minimum value (e.g., `i32::MIN` for values of type `i32`), then the /// minimum value will be returned again and `true` will be returned for an overflow happening. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(2", stringify!($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 intrinsics::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!($SelfT),".overflowing_shl(4), (0x10, false));")] /// assert_eq!(0x1i32.overflowing_shl(36), (0x10, true)); #[doc = concat!("assert_eq!(0x10", stringify!($SelfT), ".overflowing_shl(", stringify!($BITS_MINUS_ONE), "), (0, false));")] /// ``` #[stable(feature = "wrapping", since = "1.7.0")] #[rustc_const_stable(feature = "const_int_methods", since = "1.32.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn overflowing_shl(self, rhs: u32) -> (Self, bool) { (self.wrapping_shl(rhs), rhs >= Self::BITS) } /// Shifts self right by `rhs` bits. /// /// Returns a tuple of the shifted version of self along with a boolean indicating whether the shift /// value was larger than or equal to the number of bits. If the shift value is too large, then value is /// masked (N-1) where N is the number of bits, and this value is then used to perform the shift. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("assert_eq!(0x10", stringify!($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!($SelfT), ".overflowing_pow(4), (81, false));")] /// assert_eq!(3i8.overflowing_pow(5), (-13, true)); /// ``` #[stable(feature = "no_panic_pow", since = "1.34.0")] #[rustc_const_stable(feature = "const_int_pow", since = "1.50.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn overflowing_pow(self, mut exp: u32) -> (Self, bool) { if exp == 0 { return (1,false); } let mut base = self; let mut acc: Self = 1; let mut overflown = false; // Scratch space for storing results of overflowing_mul. let mut r; loop { if (exp & 1) == 1 { r = acc.overflowing_mul(base); // since exp!=0, finally the exp must be 1. if exp == 1 { r.1 |= overflown; return r; } acc = r.0; overflown |= r.1; } exp /= 2; r = base.overflowing_mul(base); base = r.0; overflown |= r.1; } } /// Raises self to the power of `exp`, using exponentiation by squaring. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("let x: ", stringify!($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] #[rustc_allow_const_fn_unstable(is_val_statically_known)] pub const fn pow(self, mut exp: u32) -> Self { if exp == 0 { return 1; } let mut base = self; let mut acc = 1; if intrinsics::is_val_statically_known(exp) { 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 } else { // This is faster than the above when the exponent is not known // at compile time. We can't use the same code for the constant // exponent case because LLVM is currently unable to unroll // this loop. loop { if (exp & 1) == 1 { acc = acc * base; // since exp!=0, finally the exp must be 1. if exp == 1 { return acc; } } exp /= 2; base = base * base; } } } /// Returns the square root of the number, rounded down. /// /// # Panics /// /// This function will panic if `self` is negative. /// /// # Examples /// /// Basic usage: /// ``` #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".isqrt(), 3);")] /// ``` #[stable(feature = "isqrt", since = "CURRENT_RUSTC_VERSION")] #[rustc_const_stable(feature = "isqrt", since = "CURRENT_RUSTC_VERSION")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn isqrt(self) -> Self { match self.checked_isqrt() { Some(sqrt) => sqrt, None => crate::num::int_sqrt::panic_for_negative_argument(), } } /// Calculates the quotient of Euclidean division of `self` by `rhs`. /// /// This computes the integer `q` such that `self = q * rhs + r`, with /// `r = self.rem_euclid(rhs)` and `0 <= r < abs(rhs)`. /// /// In other words, the result is `self / rhs` rounded to the integer `q` /// such that `self >= q * rhs`. /// If `self > 0`, this is equal to rounding towards zero (the default in Rust); /// if `self < 0`, this is equal to rounding away from zero (towards +/- infinity). /// If `rhs > 0`, this is equal to rounding towards -infinity; /// if `rhs < 0`, this is equal to rounding towards +infinity. /// /// # Panics /// /// This function will panic if `rhs` is 0 or if `self` is `Self::MIN` /// and `rhs` is -1. This behavior is not affected by the `overflow-checks` flag. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("let a: ", stringify!($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] #[track_caller] 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)`, the result satisfies /// `self = rhs * self.div_euclid(rhs) + r` and `0 <= r < abs(rhs)`. /// /// # Panics /// /// This function will panic if `rhs` is 0 or if `self` is `Self::MIN` and /// `rhs` is -1. This behavior is not affected by the `overflow-checks` flag. /// /// # Examples /// /// Basic usage: /// /// ``` #[doc = concat!("let a: ", stringify!($SelfT), " = 7; // or any other integer type")] /// let b = 4; /// /// assert_eq!(a.rem_euclid(b), 3); /// assert_eq!((-a).rem_euclid(b), 1); /// assert_eq!(a.rem_euclid(-b), 3); /// assert_eq!((-a).rem_euclid(-b), 1); /// ``` /// /// This will panic: /// ```should_panic #[doc = concat!("let _ = ", stringify!($SelfT), "::MIN.rem_euclid(-1);")] /// ``` #[doc(alias = "modulo", alias = "mod")] #[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] #[track_caller] 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 0 or if `self` is `Self::MIN` /// and `rhs` is -1. This behavior is not affected by the `overflow-checks` flag. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(int_roundings)] #[doc = concat!("let a: ", stringify!($SelfT)," = 8;")] /// let b = 3; /// /// assert_eq!(a.div_floor(b), 2); /// assert_eq!(a.div_floor(-b), -3); /// assert_eq!((-a).div_floor(b), -3); /// assert_eq!((-a).div_floor(-b), 2); /// ``` #[unstable(feature = "int_roundings", issue = "88581")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] #[track_caller] pub const fn div_floor(self, rhs: Self) -> Self { let d = self / rhs; let r = self % rhs; // If the remainder is non-zero, we need to subtract one if the // signs of self and rhs differ, as this means we rounded upwards // instead of downwards. We do this branchlessly by creating a mask // which is all-ones iff the signs differ, and 0 otherwise. Then by // adding this mask (which corresponds to the signed value -1), we // get our correction. let correction = (self ^ rhs) >> (Self::BITS - 1); if r != 0 { d + correction } else { d } } /// Calculates the quotient of `self` and `rhs`, rounding the result towards positive infinity. /// /// # Panics /// /// This function will panic if `rhs` is 0 or if `self` is `Self::MIN` /// and `rhs` is -1. This behavior is not affected by the `overflow-checks` flag. /// /// # Examples /// /// Basic usage: /// /// ``` /// #![feature(int_roundings)] #[doc = concat!("let a: ", stringify!($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] #[track_caller] pub const fn div_ceil(self, rhs: Self) -> Self { let d = self / rhs; let r = self % rhs; // When remainder is non-zero we have a.div_ceil(b) == 1 + a.div_floor(b), // so we can re-use the algorithm from div_floor, just adding 1. let correction = 1 + ((self ^ rhs) >> (Self::BITS - 1)); if r != 0 { d + correction } 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 { // 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 { if self <= 0 || base <= 1 { None } else { // Delegate to the unsigned implementation. // The condition makes sure that both casts are exact. (self as $UnsignedT).checked_ilog(base as $UnsignedT) } } /// Returns the base 2 logarithm of the number, rounded down. /// /// Returns `None` if the number is negative or zero. /// /// # Examples /// /// ``` #[doc = concat!("assert_eq!(2", stringify!($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 { 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!($SelfT), ".checked_ilog10(), Some(1));")] /// ``` #[stable(feature = "int_log", since = "1.67.0")] #[rustc_const_stable(feature = "int_log", since = "1.67.0")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] pub const fn checked_ilog10(self) -> Option { if self > 0 { Some(int_log10::$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. If you do not want this behavior, consider /// using [`unsigned_abs`](Self::unsigned_abs) instead. /// /// # 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)] pub const fn signum(self) -> Self { // Picking the right way to phrase this is complicated // () // 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. // FIXME(const-hack): replace with cmp if self < 0 { -1 } else if self == 0 { 0 } else { 1 } } /// 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 } /// Returns 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.to_be().to_ne_bytes() } /// Returns 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.to_le().to_ne_bytes() } /// Returns 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::()] { // SAFETY: integers are plain old datatypes so we can always transmute them to // arrays of bytes unsafe { mem::transmute(self) } } /// Creates 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::from_be(Self::from_ne_bytes(bytes)) } /// Creates 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::from_le(Self::from_ne_bytes(bytes)) } /// Creates 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!($SelfT), "::from_ne_bytes(int_bytes.try_into().unwrap())")] /// } /// ``` #[stable(feature = "int_to_from_bytes", since = "1.32.0")] #[rustc_const_stable(feature = "const_int_conversion", since = "1.44.0")] #[must_use] // SAFETY: const sound because integers are plain old datatypes so we can always // transmute to them #[inline] pub const fn from_ne_bytes(bytes: [u8; mem::size_of::()]) -> Self { // SAFETY: integers are plain old datatypes so we can always transmute to them unsafe { mem::transmute(bytes) } } /// New code should prefer to use #[doc = concat!("[`", stringify!($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")] #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_min_value")] pub const fn min_value() -> Self { Self::MIN } /// New code should prefer to use #[doc = concat!("[`", stringify!($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")] #[rustc_diagnostic_item = concat!(stringify!($SelfT), "_legacy_fn_max_value")] pub const fn max_value() -> Self { Self::MAX } } }