| //! Definitions of integer that is known not to equal zero. |
| |
| use crate::fmt; |
| use crate::ops::{BitOr, BitOrAssign, Div, Rem}; |
| use crate::str::FromStr; |
| |
| use super::from_str_radix; |
| use super::{IntErrorKind, ParseIntError}; |
| use crate::intrinsics; |
| |
| macro_rules! impl_nonzero_fmt { |
| ( #[$stability: meta] ( $( $Trait: ident ),+ ) for $Ty: ident ) => { |
| $( |
| #[$stability] |
| impl fmt::$Trait for $Ty { |
| #[inline] |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| self.get().fmt(f) |
| } |
| } |
| )+ |
| } |
| } |
| |
| macro_rules! nonzero_integers { |
| ( $( #[$stability: meta] #[$const_new_unchecked_stability: meta] $Ty: ident($Int: ty); )+ ) => { |
| $( |
| /// An integer that is known not to equal zero. |
| /// |
| /// This enables some memory layout optimization. |
| #[doc = concat!("For example, `Option<", stringify!($Ty), ">` is the same size as `", stringify!($Int), "`:")] |
| /// |
| /// ```rust |
| /// use std::mem::size_of; |
| #[doc = concat!("assert_eq!(size_of::<Option<core::num::", stringify!($Ty), ">>(), size_of::<", stringify!($Int), ">());")] |
| /// ``` |
| #[$stability] |
| #[derive(Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)] |
| #[repr(transparent)] |
| #[rustc_layout_scalar_valid_range_start(1)] |
| #[rustc_nonnull_optimization_guaranteed] |
| #[rustc_diagnostic_item = stringify!($Ty)] |
| pub struct $Ty($Int); |
| |
| impl $Ty { |
| /// Creates a non-zero without checking whether the value is non-zero. |
| /// This results in undefined behaviour if the value is zero. |
| /// |
| /// # Safety |
| /// |
| /// The value must not be zero. |
| #[$stability] |
| #[$const_new_unchecked_stability] |
| #[must_use] |
| #[inline] |
| pub const unsafe fn new_unchecked(n: $Int) -> Self { |
| // SAFETY: this is guaranteed to be safe by the caller. |
| unsafe { |
| core::intrinsics::assert_unsafe_precondition!( |
| concat!(stringify!($Ty), "::new_unchecked requires a non-zero argument"), |
| (n: $Int) => n != 0 |
| ); |
| Self(n) |
| } |
| } |
| |
| /// Creates a non-zero if the given value is not zero. |
| #[$stability] |
| #[rustc_const_stable(feature = "const_nonzero_int_methods", since = "1.47.0")] |
| #[must_use] |
| #[inline] |
| pub const fn new(n: $Int) -> Option<Self> { |
| if n != 0 { |
| // SAFETY: we just checked that there's no `0` |
| Some(unsafe { Self(n) }) |
| } else { |
| None |
| } |
| } |
| |
| /// Returns the value as a primitive type. |
| #[$stability] |
| #[inline] |
| #[rustc_const_stable(feature = "const_nonzero_get", since = "1.34.0")] |
| pub const fn get(self) -> $Int { |
| self.0 |
| } |
| |
| } |
| |
| #[stable(feature = "from_nonzero", since = "1.31.0")] |
| #[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] |
| impl const From<$Ty> for $Int { |
| #[doc = concat!("Converts a `", stringify!($Ty), "` into an `", stringify!($Int), "`")] |
| #[inline] |
| fn from(nonzero: $Ty) -> Self { |
| nonzero.0 |
| } |
| } |
| |
| #[stable(feature = "nonzero_bitor", since = "1.45.0")] |
| #[rustc_const_unstable(feature = "const_ops", issue = "90080")] |
| impl const BitOr for $Ty { |
| type Output = Self; |
| #[inline] |
| fn bitor(self, rhs: Self) -> Self::Output { |
| // SAFETY: since `self` and `rhs` are both nonzero, the |
| // result of the bitwise-or will be nonzero. |
| unsafe { $Ty::new_unchecked(self.get() | rhs.get()) } |
| } |
| } |
| |
| #[stable(feature = "nonzero_bitor", since = "1.45.0")] |
| #[rustc_const_unstable(feature = "const_ops", issue = "90080")] |
| impl const BitOr<$Int> for $Ty { |
| type Output = Self; |
| #[inline] |
| fn bitor(self, rhs: $Int) -> Self::Output { |
| // SAFETY: since `self` is nonzero, the result of the |
| // bitwise-or will be nonzero regardless of the value of |
| // `rhs`. |
| unsafe { $Ty::new_unchecked(self.get() | rhs) } |
| } |
| } |
| |
| #[stable(feature = "nonzero_bitor", since = "1.45.0")] |
| #[rustc_const_unstable(feature = "const_ops", issue = "90080")] |
| impl const BitOr<$Ty> for $Int { |
| type Output = $Ty; |
| #[inline] |
| fn bitor(self, rhs: $Ty) -> Self::Output { |
| // SAFETY: since `rhs` is nonzero, the result of the |
| // bitwise-or will be nonzero regardless of the value of |
| // `self`. |
| unsafe { $Ty::new_unchecked(self | rhs.get()) } |
| } |
| } |
| |
| #[stable(feature = "nonzero_bitor", since = "1.45.0")] |
| #[rustc_const_unstable(feature = "const_ops", issue = "90080")] |
| impl const BitOrAssign for $Ty { |
| #[inline] |
| fn bitor_assign(&mut self, rhs: Self) { |
| *self = *self | rhs; |
| } |
| } |
| |
| #[stable(feature = "nonzero_bitor", since = "1.45.0")] |
| #[rustc_const_unstable(feature = "const_ops", issue = "90080")] |
| impl const BitOrAssign<$Int> for $Ty { |
| #[inline] |
| fn bitor_assign(&mut self, rhs: $Int) { |
| *self = *self | rhs; |
| } |
| } |
| |
| impl_nonzero_fmt! { |
| #[$stability] (Debug, Display, Binary, Octal, LowerHex, UpperHex) for $Ty |
| } |
| )+ |
| } |
| } |
| |
| nonzero_integers! { |
| #[stable(feature = "nonzero", since = "1.28.0")] #[rustc_const_stable(feature = "nonzero", since = "1.28.0")] NonZeroU8(u8); |
| #[stable(feature = "nonzero", since = "1.28.0")] #[rustc_const_stable(feature = "nonzero", since = "1.28.0")] NonZeroU16(u16); |
| #[stable(feature = "nonzero", since = "1.28.0")] #[rustc_const_stable(feature = "nonzero", since = "1.28.0")] NonZeroU32(u32); |
| #[stable(feature = "nonzero", since = "1.28.0")] #[rustc_const_stable(feature = "nonzero", since = "1.28.0")] NonZeroU64(u64); |
| #[stable(feature = "nonzero", since = "1.28.0")] #[rustc_const_stable(feature = "nonzero", since = "1.28.0")] NonZeroU128(u128); |
| #[stable(feature = "nonzero", since = "1.28.0")] #[rustc_const_stable(feature = "nonzero", since = "1.28.0")] NonZeroUsize(usize); |
| #[stable(feature = "signed_nonzero", since = "1.34.0")] #[rustc_const_stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI8(i8); |
| #[stable(feature = "signed_nonzero", since = "1.34.0")] #[rustc_const_stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI16(i16); |
| #[stable(feature = "signed_nonzero", since = "1.34.0")] #[rustc_const_stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI32(i32); |
| #[stable(feature = "signed_nonzero", since = "1.34.0")] #[rustc_const_stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI64(i64); |
| #[stable(feature = "signed_nonzero", since = "1.34.0")] #[rustc_const_stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroI128(i128); |
| #[stable(feature = "signed_nonzero", since = "1.34.0")] #[rustc_const_stable(feature = "signed_nonzero", since = "1.34.0")] NonZeroIsize(isize); |
| } |
| |
| macro_rules! from_str_radix_nzint_impl { |
| ($($t:ty)*) => {$( |
| #[stable(feature = "nonzero_parse", since = "1.35.0")] |
| impl FromStr for $t { |
| type Err = ParseIntError; |
| fn from_str(src: &str) -> Result<Self, Self::Err> { |
| Self::new(from_str_radix(src, 10)?) |
| .ok_or(ParseIntError { |
| kind: IntErrorKind::Zero |
| }) |
| } |
| } |
| )*} |
| } |
| |
| from_str_radix_nzint_impl! { NonZeroU8 NonZeroU16 NonZeroU32 NonZeroU64 NonZeroU128 NonZeroUsize |
| NonZeroI8 NonZeroI16 NonZeroI32 NonZeroI64 NonZeroI128 NonZeroIsize } |
| |
| macro_rules! nonzero_leading_trailing_zeros { |
| ( $( $Ty: ident($Uint: ty) , $LeadingTestExpr:expr ;)+ ) => { |
| $( |
| impl $Ty { |
| /// Returns the number of leading zeros in the binary representation of `self`. |
| /// |
| /// On many architectures, this function can perform better than `leading_zeros()` on the underlying integer type, as special handling of zero can be avoided. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = std::num::", stringify!($Ty), "::new(", stringify!($LeadingTestExpr), ").unwrap();")] |
| /// |
| /// assert_eq!(n.leading_zeros(), 0); |
| /// ``` |
| #[stable(feature = "nonzero_leading_trailing_zeros", since = "1.53.0")] |
| #[rustc_const_stable(feature = "nonzero_leading_trailing_zeros", since = "1.53.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn leading_zeros(self) -> u32 { |
| // SAFETY: since `self` cannot be zero, it is safe to call `ctlz_nonzero`. |
| unsafe { intrinsics::ctlz_nonzero(self.0 as $Uint) as u32 } |
| } |
| |
| /// Returns the number of trailing zeros in the binary representation |
| /// of `self`. |
| /// |
| /// On many architectures, this function can perform better than `trailing_zeros()` on the underlying integer type, as special handling of zero can be avoided. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let n = std::num::", stringify!($Ty), "::new(0b0101000).unwrap();")] |
| /// |
| /// assert_eq!(n.trailing_zeros(), 3); |
| /// ``` |
| #[stable(feature = "nonzero_leading_trailing_zeros", since = "1.53.0")] |
| #[rustc_const_stable(feature = "nonzero_leading_trailing_zeros", since = "1.53.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn trailing_zeros(self) -> u32 { |
| // SAFETY: since `self` cannot be zero, it is safe to call `cttz_nonzero`. |
| unsafe { intrinsics::cttz_nonzero(self.0 as $Uint) as u32 } |
| } |
| |
| } |
| )+ |
| } |
| } |
| |
| nonzero_leading_trailing_zeros! { |
| NonZeroU8(u8), u8::MAX; |
| NonZeroU16(u16), u16::MAX; |
| NonZeroU32(u32), u32::MAX; |
| NonZeroU64(u64), u64::MAX; |
| NonZeroU128(u128), u128::MAX; |
| NonZeroUsize(usize), usize::MAX; |
| NonZeroI8(u8), -1i8; |
| NonZeroI16(u16), -1i16; |
| NonZeroI32(u32), -1i32; |
| NonZeroI64(u64), -1i64; |
| NonZeroI128(u128), -1i128; |
| NonZeroIsize(usize), -1isize; |
| } |
| |
| macro_rules! nonzero_integers_div { |
| ( $( $Ty: ident($Int: ty); )+ ) => { |
| $( |
| #[stable(feature = "nonzero_div", since = "1.51.0")] |
| #[rustc_const_unstable(feature = "const_ops", issue = "90080")] |
| impl const Div<$Ty> for $Int { |
| type Output = $Int; |
| /// This operation rounds towards zero, |
| /// truncating any fractional part of the exact result, and cannot panic. |
| #[inline] |
| fn div(self, other: $Ty) -> $Int { |
| // SAFETY: div by zero is checked because `other` is a nonzero, |
| // and MIN/-1 is checked because `self` is an unsigned int. |
| unsafe { crate::intrinsics::unchecked_div(self, other.get()) } |
| } |
| } |
| |
| #[stable(feature = "nonzero_div", since = "1.51.0")] |
| #[rustc_const_unstable(feature = "const_ops", issue = "90080")] |
| impl const Rem<$Ty> for $Int { |
| type Output = $Int; |
| /// This operation satisfies `n % d == n - (n / d) * d`, and cannot panic. |
| #[inline] |
| fn rem(self, other: $Ty) -> $Int { |
| // SAFETY: rem by zero is checked because `other` is a nonzero, |
| // and MIN/-1 is checked because `self` is an unsigned int. |
| unsafe { crate::intrinsics::unchecked_rem(self, other.get()) } |
| } |
| } |
| )+ |
| } |
| } |
| |
| nonzero_integers_div! { |
| NonZeroU8(u8); |
| NonZeroU16(u16); |
| NonZeroU32(u32); |
| NonZeroU64(u64); |
| NonZeroU128(u128); |
| NonZeroUsize(usize); |
| } |
| |
| // A bunch of methods for unsigned nonzero types only. |
| macro_rules! nonzero_unsigned_operations { |
| ( $( $Ty: ident($Int: ident); )+ ) => { |
| $( |
| impl $Ty { |
| /// Adds an unsigned integer to a non-zero value. |
| /// Checks for overflow and returns [`None`] on overflow. |
| /// As a consequence, the result cannot wrap to zero. |
| /// |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")] |
| #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")] |
| #[doc = concat!("let max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX)?;")] |
| /// |
| /// assert_eq!(Some(two), one.checked_add(1)); |
| /// assert_eq!(None, max.checked_add(1)); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_add(self, other: $Int) -> Option<$Ty> { |
| if let Some(result) = self.get().checked_add(other) { |
| // SAFETY: $Int::checked_add returns None on overflow |
| // so the result cannot be zero. |
| Some(unsafe { $Ty::new_unchecked(result) }) |
| } else { |
| None |
| } |
| } |
| |
| /// Adds an unsigned integer to a non-zero value. |
| #[doc = concat!("Return [`", stringify!($Int), "::MAX`] on overflow.")] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")] |
| #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")] |
| #[doc = concat!("let max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX)?;")] |
| /// |
| /// assert_eq!(two, one.saturating_add(1)); |
| /// assert_eq!(max, max.saturating_add(1)); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_add(self, other: $Int) -> $Ty { |
| // SAFETY: $Int::saturating_add returns $Int::MAX on overflow |
| // so the result cannot be zero. |
| unsafe { $Ty::new_unchecked(self.get().saturating_add(other)) } |
| } |
| |
| /// Adds an unsigned integer to a non-zero value, |
| /// assuming overflow cannot occur. |
| /// Overflow is unchecked, and it is undefined behaviour to overflow |
| /// *even if the result would wrap to a non-zero value*. |
| /// The behaviour is undefined as soon as |
| #[doc = concat!("`self + rhs > ", stringify!($Int), "::MAX`.")] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// #![feature(nonzero_ops)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")] |
| #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")] |
| /// |
| /// assert_eq!(two, unsafe { one.unchecked_add(1) }); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[unstable(feature = "nonzero_ops", issue = "84186")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const unsafe fn unchecked_add(self, other: $Int) -> $Ty { |
| // SAFETY: The caller ensures there is no overflow. |
| unsafe { $Ty::new_unchecked(self.get().unchecked_add(other)) } |
| } |
| |
| /// Returns the smallest power of two greater than or equal to n. |
| /// Checks for overflow and returns [`None`] |
| /// if the next power of two is greater than the type’s maximum value. |
| /// As a consequence, the result cannot wrap to zero. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")] |
| #[doc = concat!("let three = ", stringify!($Ty), "::new(3)?;")] |
| #[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")] |
| #[doc = concat!("let max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX)?;")] |
| /// |
| /// assert_eq!(Some(two), two.checked_next_power_of_two() ); |
| /// assert_eq!(Some(four), three.checked_next_power_of_two() ); |
| /// assert_eq!(None, max.checked_next_power_of_two() ); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_next_power_of_two(self) -> Option<$Ty> { |
| if let Some(nz) = self.get().checked_next_power_of_two() { |
| // SAFETY: The next power of two is positive |
| // and overflow is checked. |
| Some(unsafe { $Ty::new_unchecked(nz) }) |
| } else { |
| None |
| } |
| } |
| |
| /// Returns the base 2 logarithm of the number, rounded down. |
| /// |
| /// This is the same operation as |
| #[doc = concat!("[`", stringify!($Int), "::ilog2`],")] |
| /// except that it has no failure cases to worry about |
| /// since this value can never be zero. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(7).unwrap().ilog2(), 2);")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(8).unwrap().ilog2(), 3);")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(9).unwrap().ilog2(), 3);")] |
| /// ``` |
| #[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 ilog2(self) -> u32 { |
| Self::BITS - 1 - self.leading_zeros() |
| } |
| |
| /// Returns the base 10 logarithm of the number, rounded down. |
| /// |
| /// This is the same operation as |
| #[doc = concat!("[`", stringify!($Int), "::ilog10`],")] |
| /// except that it has no failure cases to worry about |
| /// since this value can never be zero. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(99).unwrap().ilog10(), 1);")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(100).unwrap().ilog10(), 2);")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(101).unwrap().ilog10(), 2);")] |
| /// ``` |
| #[stable(feature = "int_log", since = "1.67.0")] |
| #[rustc_const_stable(feature = "int_log", since = "1.67.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn ilog10(self) -> u32 { |
| super::int_log10::$Int(self.0) |
| } |
| } |
| )+ |
| } |
| } |
| |
| nonzero_unsigned_operations! { |
| NonZeroU8(u8); |
| NonZeroU16(u16); |
| NonZeroU32(u32); |
| NonZeroU64(u64); |
| NonZeroU128(u128); |
| NonZeroUsize(usize); |
| } |
| |
| // A bunch of methods for signed nonzero types only. |
| macro_rules! nonzero_signed_operations { |
| ( $( $Ty: ident($Int: ty) -> $Uty: ident($Uint: ty); )+ ) => { |
| $( |
| impl $Ty { |
| /// Computes the absolute value of self. |
| #[doc = concat!("See [`", stringify!($Int), "::abs`]")] |
| /// for documentation on overflow behaviour. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")] |
| #[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")] |
| /// |
| /// assert_eq!(pos, pos.abs()); |
| /// assert_eq!(pos, neg.abs()); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn abs(self) -> $Ty { |
| // SAFETY: This cannot overflow to zero. |
| unsafe { $Ty::new_unchecked(self.get().abs()) } |
| } |
| |
| /// Checked absolute value. |
| /// Checks for overflow and returns [`None`] if |
| #[doc = concat!("`self == ", stringify!($Int), "::MIN`.")] |
| /// The result cannot be zero. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")] |
| #[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")] |
| #[doc = concat!("let min = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN)?;")] |
| /// |
| /// assert_eq!(Some(pos), neg.checked_abs()); |
| /// assert_eq!(None, min.checked_abs()); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_abs(self) -> Option<$Ty> { |
| if let Some(nz) = self.get().checked_abs() { |
| // SAFETY: absolute value of nonzero cannot yield zero values. |
| Some(unsafe { $Ty::new_unchecked(nz) }) |
| } else { |
| None |
| } |
| } |
| |
| /// Computes the absolute value of self, |
| /// with overflow information, see |
| #[doc = concat!("[`", stringify!($Int), "::overflowing_abs`].")] |
| /// |
| /// # Example |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")] |
| #[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")] |
| #[doc = concat!("let min = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN)?;")] |
| /// |
| /// assert_eq!((pos, false), pos.overflowing_abs()); |
| /// assert_eq!((pos, false), neg.overflowing_abs()); |
| /// assert_eq!((min, true), min.overflowing_abs()); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn overflowing_abs(self) -> ($Ty, bool) { |
| let (nz, flag) = self.get().overflowing_abs(); |
| ( |
| // SAFETY: absolute value of nonzero cannot yield zero values. |
| unsafe { $Ty::new_unchecked(nz) }, |
| flag, |
| ) |
| } |
| |
| /// Saturating absolute value, see |
| #[doc = concat!("[`", stringify!($Int), "::saturating_abs`].")] |
| /// |
| /// # Example |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")] |
| #[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")] |
| #[doc = concat!("let min = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN)?;")] |
| #[doc = concat!("let min_plus = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN + 1)?;")] |
| #[doc = concat!("let max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX)?;")] |
| /// |
| /// assert_eq!(pos, pos.saturating_abs()); |
| /// assert_eq!(pos, neg.saturating_abs()); |
| /// assert_eq!(max, min.saturating_abs()); |
| /// assert_eq!(max, min_plus.saturating_abs()); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_abs(self) -> $Ty { |
| // SAFETY: absolute value of nonzero cannot yield zero values. |
| unsafe { $Ty::new_unchecked(self.get().saturating_abs()) } |
| } |
| |
| /// Wrapping absolute value, see |
| #[doc = concat!("[`", stringify!($Int), "::wrapping_abs`].")] |
| /// |
| /// # Example |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos = ", stringify!($Ty), "::new(1)?;")] |
| #[doc = concat!("let neg = ", stringify!($Ty), "::new(-1)?;")] |
| #[doc = concat!("let min = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN)?;")] |
| #[doc = concat!("# let max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX)?;")] |
| /// |
| /// assert_eq!(pos, pos.wrapping_abs()); |
| /// assert_eq!(pos, neg.wrapping_abs()); |
| /// assert_eq!(min, min.wrapping_abs()); |
| /// # // FIXME: add once Neg is implemented? |
| /// # // assert_eq!(max, (-max).wrapping_abs()); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn wrapping_abs(self) -> $Ty { |
| // SAFETY: absolute value of nonzero cannot yield zero values. |
| unsafe { $Ty::new_unchecked(self.get().wrapping_abs()) } |
| } |
| |
| /// Computes the absolute value of self |
| /// without any wrapping or panicking. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| #[doc = concat!("# use std::num::", stringify!($Uty), ";")] |
| /// |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let u_pos = ", stringify!($Uty), "::new(1)?;")] |
| #[doc = concat!("let i_pos = ", stringify!($Ty), "::new(1)?;")] |
| #[doc = concat!("let i_neg = ", stringify!($Ty), "::new(-1)?;")] |
| #[doc = concat!("let i_min = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN)?;")] |
| #[doc = concat!("let u_max = ", stringify!($Uty), "::new(", |
| stringify!($Uint), "::MAX / 2 + 1)?;")] |
| /// |
| /// assert_eq!(u_pos, i_pos.unsigned_abs()); |
| /// assert_eq!(u_pos, i_neg.unsigned_abs()); |
| /// assert_eq!(u_max, i_min.unsigned_abs()); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn unsigned_abs(self) -> $Uty { |
| // SAFETY: absolute value of nonzero cannot yield zero values. |
| unsafe { $Uty::new_unchecked(self.get().unsigned_abs()) } |
| } |
| |
| /// Returns `true` if `self` is negative and `false` if the |
| /// number is positive. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| /// #![feature(nonzero_negation_ops)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")] |
| #[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")] |
| /// |
| /// assert!(neg_five.is_negative()); |
| /// assert!(!pos_five.is_negative()); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[must_use] |
| #[inline] |
| #[unstable(feature = "nonzero_negation_ops", issue = "102443")] |
| pub const fn is_negative(self) -> bool { |
| self.get().is_negative() |
| } |
| |
| /// Checked negation. Computes `-self`, returning `None` if `self == i32::MIN`. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| /// #![feature(nonzero_negation_ops)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")] |
| #[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")] |
| #[doc = concat!("let min = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN)?;")] |
| /// |
| /// assert_eq!(pos_five.checked_neg(), Some(neg_five)); |
| /// assert_eq!(min.checked_neg(), None); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[inline] |
| #[unstable(feature = "nonzero_negation_ops", issue = "102443")] |
| pub const fn checked_neg(self) -> Option<$Ty> { |
| if let Some(result) = self.get().checked_neg() { |
| // SAFETY: negation of nonzero cannot yield zero values. |
| return Some(unsafe { $Ty::new_unchecked(result) }); |
| } |
| None |
| } |
| |
| /// Negates self, overflowing if this is equal to the minimum value. |
| /// |
| #[doc = concat!("See [`", stringify!($Int), "::overflowing_neg`]")] |
| /// for documentation on overflow behaviour. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| /// #![feature(nonzero_negation_ops)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")] |
| #[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")] |
| #[doc = concat!("let min = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN)?;")] |
| /// |
| /// assert_eq!(pos_five.overflowing_neg(), (neg_five, false)); |
| /// assert_eq!(min.overflowing_neg(), (min, true)); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[inline] |
| #[unstable(feature = "nonzero_negation_ops", issue = "102443")] |
| pub const fn overflowing_neg(self) -> ($Ty, bool) { |
| let (result, overflow) = self.get().overflowing_neg(); |
| // SAFETY: negation of nonzero cannot yield zero values. |
| ((unsafe { $Ty::new_unchecked(result) }), overflow) |
| } |
| |
| /// Saturating negation. Computes `-self`, returning `MAX` if |
| /// `self == i32::MIN` instead of overflowing. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| /// #![feature(nonzero_negation_ops)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")] |
| #[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")] |
| #[doc = concat!("let min = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN)?;")] |
| #[doc = concat!("let min_plus_one = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN + 1)?;")] |
| #[doc = concat!("let max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX)?;")] |
| /// |
| /// assert_eq!(pos_five.saturating_neg(), neg_five); |
| /// assert_eq!(min.saturating_neg(), max); |
| /// assert_eq!(max.saturating_neg(), min_plus_one); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[inline] |
| #[unstable(feature = "nonzero_negation_ops", issue = "102443")] |
| pub const fn saturating_neg(self) -> $Ty { |
| if let Some(result) = self.checked_neg() { |
| return result; |
| } |
| $Ty::MAX |
| } |
| |
| /// Wrapping (modular) negation. Computes `-self`, wrapping around at the boundary |
| /// of the type. |
| /// |
| #[doc = concat!("See [`", stringify!($Int), "::wrapping_neg`]")] |
| /// for documentation on overflow behaviour. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| /// #![feature(nonzero_negation_ops)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")] |
| #[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")] |
| #[doc = concat!("let min = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MIN)?;")] |
| /// |
| /// assert_eq!(pos_five.wrapping_neg(), neg_five); |
| /// assert_eq!(min.wrapping_neg(), min); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[inline] |
| #[unstable(feature = "nonzero_negation_ops", issue = "102443")] |
| pub const fn wrapping_neg(self) -> $Ty { |
| let result = self.get().wrapping_neg(); |
| // SAFETY: negation of nonzero cannot yield zero values. |
| unsafe { $Ty::new_unchecked(result) } |
| } |
| } |
| )+ |
| } |
| } |
| |
| nonzero_signed_operations! { |
| NonZeroI8(i8) -> NonZeroU8(u8); |
| NonZeroI16(i16) -> NonZeroU16(u16); |
| NonZeroI32(i32) -> NonZeroU32(u32); |
| NonZeroI64(i64) -> NonZeroU64(u64); |
| NonZeroI128(i128) -> NonZeroU128(u128); |
| NonZeroIsize(isize) -> NonZeroUsize(usize); |
| } |
| |
| // A bunch of methods for both signed and unsigned nonzero types. |
| macro_rules! nonzero_unsigned_signed_operations { |
| ( $( $signedness:ident $Ty: ident($Int: ty); )+ ) => { |
| $( |
| impl $Ty { |
| /// Multiplies two non-zero integers together. |
| /// Checks for overflow and returns [`None`] on overflow. |
| /// As a consequence, the result cannot wrap to zero. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")] |
| #[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")] |
| #[doc = concat!("let max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX)?;")] |
| /// |
| /// assert_eq!(Some(four), two.checked_mul(two)); |
| /// assert_eq!(None, max.checked_mul(two)); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_mul(self, other: $Ty) -> Option<$Ty> { |
| if let Some(result) = self.get().checked_mul(other.get()) { |
| // SAFETY: checked_mul returns None on overflow |
| // and `other` is also non-null |
| // so the result cannot be zero. |
| Some(unsafe { $Ty::new_unchecked(result) }) |
| } else { |
| None |
| } |
| } |
| |
| /// Multiplies two non-zero integers together. |
| #[doc = concat!("Return [`", stringify!($Int), "::MAX`] on overflow.")] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")] |
| #[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")] |
| #[doc = concat!("let max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX)?;")] |
| /// |
| /// assert_eq!(four, two.saturating_mul(two)); |
| /// assert_eq!(max, four.saturating_mul(max)); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_mul(self, other: $Ty) -> $Ty { |
| // SAFETY: saturating_mul returns u*::MAX on overflow |
| // and `other` is also non-null |
| // so the result cannot be zero. |
| unsafe { $Ty::new_unchecked(self.get().saturating_mul(other.get())) } |
| } |
| |
| /// Multiplies two non-zero integers together, |
| /// assuming overflow cannot occur. |
| /// Overflow is unchecked, and it is undefined behaviour to overflow |
| /// *even if the result would wrap to a non-zero value*. |
| /// The behaviour is undefined as soon as |
| #[doc = sign_dependent_expr!{ |
| $signedness ? |
| if signed { |
| concat!("`self * rhs > ", stringify!($Int), "::MAX`, ", |
| "or `self * rhs < ", stringify!($Int), "::MIN`.") |
| } |
| if unsigned { |
| concat!("`self * rhs > ", stringify!($Int), "::MAX`.") |
| } |
| }] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// #![feature(nonzero_ops)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")] |
| #[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")] |
| /// |
| /// assert_eq!(four, unsafe { two.unchecked_mul(two) }); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[unstable(feature = "nonzero_ops", issue = "84186")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const unsafe fn unchecked_mul(self, other: $Ty) -> $Ty { |
| // SAFETY: The caller ensures there is no overflow. |
| unsafe { $Ty::new_unchecked(self.get().unchecked_mul(other.get())) } |
| } |
| |
| /// Raises non-zero value to an integer power. |
| /// Checks for overflow and returns [`None`] on overflow. |
| /// As a consequence, the result cannot wrap to zero. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let three = ", stringify!($Ty), "::new(3)?;")] |
| #[doc = concat!("let twenty_seven = ", stringify!($Ty), "::new(27)?;")] |
| #[doc = concat!("let half_max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX / 2)?;")] |
| /// |
| /// assert_eq!(Some(twenty_seven), three.checked_pow(3)); |
| /// assert_eq!(None, half_max.checked_pow(3)); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn checked_pow(self, other: u32) -> Option<$Ty> { |
| if let Some(result) = self.get().checked_pow(other) { |
| // SAFETY: checked_pow returns None on overflow |
| // so the result cannot be zero. |
| Some(unsafe { $Ty::new_unchecked(result) }) |
| } else { |
| None |
| } |
| } |
| |
| /// Raise non-zero value to an integer power. |
| #[doc = sign_dependent_expr!{ |
| $signedness ? |
| if signed { |
| concat!("Return [`", stringify!($Int), "::MIN`] ", |
| "or [`", stringify!($Int), "::MAX`] on overflow.") |
| } |
| if unsigned { |
| concat!("Return [`", stringify!($Int), "::MAX`] on overflow.") |
| } |
| }] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// # fn main() { test().unwrap(); } |
| /// # fn test() -> Option<()> { |
| #[doc = concat!("let three = ", stringify!($Ty), "::new(3)?;")] |
| #[doc = concat!("let twenty_seven = ", stringify!($Ty), "::new(27)?;")] |
| #[doc = concat!("let max = ", stringify!($Ty), "::new(", |
| stringify!($Int), "::MAX)?;")] |
| /// |
| /// assert_eq!(twenty_seven, three.saturating_pow(3)); |
| /// assert_eq!(max, max.saturating_pow(3)); |
| /// # Some(()) |
| /// # } |
| /// ``` |
| #[stable(feature = "nonzero_checked_ops", since = "1.64.0")] |
| #[rustc_const_stable(feature = "const_nonzero_checked_ops", since = "1.64.0")] |
| #[must_use = "this returns the result of the operation, \ |
| without modifying the original"] |
| #[inline] |
| pub const fn saturating_pow(self, other: u32) -> $Ty { |
| // SAFETY: saturating_pow returns u*::MAX on overflow |
| // so the result cannot be zero. |
| unsafe { $Ty::new_unchecked(self.get().saturating_pow(other)) } |
| } |
| } |
| )+ |
| } |
| } |
| |
| // Use this when the generated code should differ between signed and unsigned types. |
| macro_rules! sign_dependent_expr { |
| (signed ? if signed { $signed_case:expr } if unsigned { $unsigned_case:expr } ) => { |
| $signed_case |
| }; |
| (unsigned ? if signed { $signed_case:expr } if unsigned { $unsigned_case:expr } ) => { |
| $unsigned_case |
| }; |
| } |
| |
| nonzero_unsigned_signed_operations! { |
| unsigned NonZeroU8(u8); |
| unsigned NonZeroU16(u16); |
| unsigned NonZeroU32(u32); |
| unsigned NonZeroU64(u64); |
| unsigned NonZeroU128(u128); |
| unsigned NonZeroUsize(usize); |
| signed NonZeroI8(i8); |
| signed NonZeroI16(i16); |
| signed NonZeroI32(i32); |
| signed NonZeroI64(i64); |
| signed NonZeroI128(i128); |
| signed NonZeroIsize(isize); |
| } |
| |
| macro_rules! nonzero_unsigned_is_power_of_two { |
| ( $( $Ty: ident )+ ) => { |
| $( |
| impl $Ty { |
| |
| /// Returns `true` if and only if `self == (1 << k)` for some `k`. |
| /// |
| /// On many architectures, this function can perform better than `is_power_of_two()` |
| /// on the underlying integer type, as special handling of zero can be avoided. |
| /// |
| /// # Examples |
| /// |
| /// Basic usage: |
| /// |
| /// ``` |
| #[doc = concat!("let eight = std::num::", stringify!($Ty), "::new(8).unwrap();")] |
| /// assert!(eight.is_power_of_two()); |
| #[doc = concat!("let ten = std::num::", stringify!($Ty), "::new(10).unwrap();")] |
| /// assert!(!ten.is_power_of_two()); |
| /// ``` |
| #[must_use] |
| #[stable(feature = "nonzero_is_power_of_two", since = "1.59.0")] |
| #[rustc_const_stable(feature = "nonzero_is_power_of_two", since = "1.59.0")] |
| #[inline] |
| pub const fn is_power_of_two(self) -> bool { |
| // LLVM 11 normalizes `unchecked_sub(x, 1) & x == 0` to the implementation seen here. |
| // On the basic x86-64 target, this saves 3 instructions for the zero check. |
| // On x86_64 with BMI1, being nonzero lets it codegen to `BLSR`, which saves an instruction |
| // compared to the `POPCNT` implementation on the underlying integer type. |
| |
| intrinsics::ctpop(self.get()) < 2 |
| } |
| |
| } |
| )+ |
| } |
| } |
| |
| nonzero_unsigned_is_power_of_two! { NonZeroU8 NonZeroU16 NonZeroU32 NonZeroU64 NonZeroU128 NonZeroUsize } |
| |
| macro_rules! nonzero_min_max_unsigned { |
| ( $( $Ty: ident($Int: ident); )+ ) => { |
| $( |
| impl $Ty { |
| /// The smallest value that can be represented by this non-zero |
| /// integer type, 1. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// #![feature(nonzero_min_max)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::MIN.get(), 1", stringify!($Int), ");")] |
| /// ``` |
| #[unstable(feature = "nonzero_min_max", issue = "89065")] |
| pub const MIN: Self = Self::new(1).unwrap(); |
| |
| /// The largest value that can be represented by this non-zero |
| /// integer type, |
| #[doc = concat!("equal to [`", stringify!($Int), "::MAX`].")] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// #![feature(nonzero_min_max)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::MAX.get(), ", stringify!($Int), "::MAX);")] |
| /// ``` |
| #[unstable(feature = "nonzero_min_max", issue = "89065")] |
| pub const MAX: Self = Self::new(<$Int>::MAX).unwrap(); |
| } |
| )+ |
| } |
| } |
| |
| macro_rules! nonzero_min_max_signed { |
| ( $( $Ty: ident($Int: ident); )+ ) => { |
| $( |
| impl $Ty { |
| /// The smallest value that can be represented by this non-zero |
| /// integer type, |
| #[doc = concat!("equal to [`", stringify!($Int), "::MIN`].")] |
| /// |
| /// Note: While most integer types are defined for every whole |
| /// number between `MIN` and `MAX`, signed non-zero integers are |
| /// a special case. They have a "gap" at 0. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// #![feature(nonzero_min_max)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::MIN.get(), ", stringify!($Int), "::MIN);")] |
| /// ``` |
| #[unstable(feature = "nonzero_min_max", issue = "89065")] |
| pub const MIN: Self = Self::new(<$Int>::MIN).unwrap(); |
| |
| /// The largest value that can be represented by this non-zero |
| /// integer type, |
| #[doc = concat!("equal to [`", stringify!($Int), "::MAX`].")] |
| /// |
| /// Note: While most integer types are defined for every whole |
| /// number between `MIN` and `MAX`, signed non-zero integers are |
| /// a special case. They have a "gap" at 0. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// #![feature(nonzero_min_max)] |
| /// |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::MAX.get(), ", stringify!($Int), "::MAX);")] |
| /// ``` |
| #[unstable(feature = "nonzero_min_max", issue = "89065")] |
| pub const MAX: Self = Self::new(<$Int>::MAX).unwrap(); |
| } |
| )+ |
| } |
| } |
| |
| nonzero_min_max_unsigned! { |
| NonZeroU8(u8); |
| NonZeroU16(u16); |
| NonZeroU32(u32); |
| NonZeroU64(u64); |
| NonZeroU128(u128); |
| NonZeroUsize(usize); |
| } |
| |
| nonzero_min_max_signed! { |
| NonZeroI8(i8); |
| NonZeroI16(i16); |
| NonZeroI32(i32); |
| NonZeroI64(i64); |
| NonZeroI128(i128); |
| NonZeroIsize(isize); |
| } |
| |
| macro_rules! nonzero_bits { |
| ( $( $Ty: ident($Int: ty); )+ ) => { |
| $( |
| impl $Ty { |
| /// The size of this non-zero integer type in bits. |
| /// |
| #[doc = concat!("This value is equal to [`", stringify!($Int), "::BITS`].")] |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| #[doc = concat!("# use std::num::", stringify!($Ty), ";")] |
| /// |
| #[doc = concat!("assert_eq!(", stringify!($Ty), "::BITS, ", stringify!($Int), "::BITS);")] |
| /// ``` |
| #[stable(feature = "nonzero_bits", since = "1.67.0")] |
| pub const BITS: u32 = <$Int>::BITS; |
| } |
| )+ |
| } |
| } |
| |
| nonzero_bits! { |
| NonZeroU8(u8); |
| NonZeroI8(i8); |
| NonZeroU16(u16); |
| NonZeroI16(i16); |
| NonZeroU32(u32); |
| NonZeroI32(i32); |
| NonZeroU64(u64); |
| NonZeroI64(i64); |
| NonZeroU128(u128); |
| NonZeroI128(i128); |
| NonZeroUsize(usize); |
| NonZeroIsize(isize); |
| } |
