diff options
Diffstat (limited to 'library/core/src/num/nonzero.rs')
| -rw-r--r-- | library/core/src/num/nonzero.rs | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs index 308d722f5d5..e02d9260a16 100644 --- a/library/core/src/num/nonzero.rs +++ b/library/core/src/num/nonzero.rs @@ -681,6 +681,54 @@ macro_rules! nonzero_integer { unsafe { NonZero::new_unchecked(n) } } + /// Returns the index of the highest bit set to one in `self`. + /// + /// # Examples + /// + /// ``` + /// #![feature(int_lowest_highest_one)] + /// + /// # use core::num::NonZero; + /// # fn main() { test().unwrap(); } + /// # fn test() -> Option<()> { + #[doc = concat!("assert_eq!(NonZero::<", stringify!($Int), ">::new(0x1)?.highest_one(), 0);")] + #[doc = concat!("assert_eq!(NonZero::<", stringify!($Int), ">::new(0x10)?.highest_one(), 4);")] + #[doc = concat!("assert_eq!(NonZero::<", stringify!($Int), ">::new(0x1f)?.highest_one(), 4);")] + /// # Some(()) + /// # } + /// ``` + #[unstable(feature = "int_lowest_highest_one", issue = "145203")] + #[must_use = "this returns the result of the operation, \ + without modifying the original"] + #[inline(always)] + pub const fn highest_one(self) -> u32 { + Self::BITS - 1 - self.leading_zeros() + } + + /// Returns the index of the lowest bit set to one in `self`. + /// + /// # Examples + /// + /// ``` + /// #![feature(int_lowest_highest_one)] + /// + /// # use core::num::NonZero; + /// # fn main() { test().unwrap(); } + /// # fn test() -> Option<()> { + #[doc = concat!("assert_eq!(NonZero::<", stringify!($Int), ">::new(0x1)?.lowest_one(), 0);")] + #[doc = concat!("assert_eq!(NonZero::<", stringify!($Int), ">::new(0x10)?.lowest_one(), 4);")] + #[doc = concat!("assert_eq!(NonZero::<", stringify!($Int), ">::new(0x1f)?.lowest_one(), 0);")] + /// # Some(()) + /// # } + /// ``` + #[unstable(feature = "int_lowest_highest_one", issue = "145203")] + #[must_use = "this returns the result of the operation, \ + without modifying the original"] + #[inline(always)] + pub const fn lowest_one(self) -> u32 { + self.trailing_zeros() + } + /// Returns the number of ones in the binary representation of `self`. /// /// # Examples |