diff --git a/core/src/num/int_macros.rs b/core/src/num/int_macros.rs index c9c6e34eaad8e..e674ce46a330f 100644 --- a/core/src/num/int_macros.rs +++ b/core/src/num/int_macros.rs @@ -183,6 +183,30 @@ macro_rules! int_impl { (self as $UnsignedT).trailing_ones() } + /// Returns the bit pattern of `self` reinterpreted as an unsigned integer of the same size. + /// + /// This is a bit safer than `as` because it wouldn't silently change the size if the code + /// is refactored. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ``` + /// #![feature(integer_sign_cast)] + /// + #[doc = concat!("let n = -1", stringify!($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 $UnsignedT + } + /// Shifts the bits to the left by a specified amount, `n`, /// wrapping the truncated bits to the end of the resulting integer. /// diff --git a/core/src/num/uint_macros.rs b/core/src/num/uint_macros.rs index 50a8f4111195d..229f5ac587806 100644 --- a/core/src/num/uint_macros.rs +++ b/core/src/num/uint_macros.rs @@ -184,6 +184,30 @@ macro_rules! uint_impl { (!self).trailing_zeros() } + /// Returns the bit pattern of `self` reinterpreted as a signed integer of the same size. + /// + /// This is a bit safer than `as` because it wouldn't silently change the size if the code + /// is refactored. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ``` + /// #![feature(integer_sign_cast)] + /// + #[doc = concat!("let n = ", stringify!($SelfT), "::MAX;")] + /// + #[doc = concat!("assert_eq!(n.cast_signed(), -1", stringify!($SignedT), ");")] + /// ``` + #[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_signed(self) -> $SignedT { + self as $SignedT + } + /// Shifts the bits to the left by a specified amount, `n`, /// wrapping the truncated bits to the end of the resulting integer. ///