diff options
| -rw-r--r-- | library/core/src/num/nonzero.rs | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs index 6b9b435d47f..e87049450e3 100644 --- a/library/core/src/num/nonzero.rs +++ b/library/core/src/num/nonzero.rs @@ -285,6 +285,57 @@ nonzero_integers_div! { NonZeroUsize(usize); } +// A bunch of methods for unsigned nonzero types only. +macro_rules! nonzero_unsigned_operations { + ( $( $Ty: ident($Int: ty); )+ ) => { + $( + impl $Ty { + /// Add an unsigned integer to a non-zero value. + /// Return [`None`] on overflow. + /// + /// # Examples + /// + /// ``` + /// #![feature(nonzero_ops)] + /// # #![feature(try_trait)] + #[doc = concat!("# use std::num::", stringify!($Ty), ";")] + /// + /// # fn main() -> Result<(), std::option::NoneError> { + #[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)); + /// # Ok(()) + /// # } + /// ``` + #[unstable(feature = "nonzero_ops", issue = "84186")] + #[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 + } + } + } + )+ + } +} + +nonzero_unsigned_operations! { + NonZeroU8(u8); + NonZeroU16(u16); + NonZeroU32(u32); + NonZeroU64(u64); + NonZeroU128(u128); + NonZeroUsize(usize); +} + macro_rules! nonzero_unsigned_is_power_of_two { ( $( $Ty: ident )+ ) => { $( |