diff options
| -rw-r--r-- | src/libcore/num/mod.rs | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/src/libcore/num/mod.rs b/src/libcore/num/mod.rs index 4b9e82c7cfe..1a8c066173b 100644 --- a/src/libcore/num/mod.rs +++ b/src/libcore/num/mod.rs @@ -5250,3 +5250,73 @@ impl_from! { u32, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0" // Float -> Float impl_from! { f32, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0")] } + +// Conversion traits for non-zero integer types +macro_rules! nzint_impl_from { + ($Small: ty, $Large: ty, #[$attr:meta], $doc: expr) => { + #[$attr] + #[doc = $doc] + impl From<$Small> for $Large { + /// Widens a non-zero integer without checking the value is zero. + /// + /// # Safety + /// + /// The value is assumed to be non-zero. + #[inline] + fn from(small: $Small) -> $Large { + unsafe { + <$Large>::new_unchecked(small.get().into()) + } + } + } + }; + ($Small: ty, $Large: ty, #[$attr:meta]) => { + nzint_impl_from!($Small, + $Large, + #[$attr], + concat!("Converts `", + stringify!($Small), + "` to `", + stringify!($Large), + "` losslessly.")); + } +} + +// Non-zero Unsigned -> Non-zero Unsigned +nzint_impl_from! { NonZeroU8, NonZeroU16, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU8, NonZeroU32, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU8, NonZeroU64, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU8, NonZeroU128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU8, NonZeroUsize, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU16, NonZeroU32, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU16, NonZeroU64, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU16, NonZeroU128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU32, NonZeroU64, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU32, NonZeroU128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU64, NonZeroU128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } + +// Non-zero Signed -> Non-zero Signed +nzint_impl_from! { NonZeroI8, NonZeroI16, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI8, NonZeroI32, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI8, NonZeroI64, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI8, NonZeroI128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI8, NonZeroIsize, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI16, NonZeroI32, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI16, NonZeroI64, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI16, NonZeroI128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI32, NonZeroI64, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI32, NonZeroI128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroI64, NonZeroI128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } + +// NonZero UnSigned -> Non-zero Signed +nzint_impl_from! { NonZeroU8, NonZeroI16, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU8, NonZeroI32, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU8, NonZeroI64, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU8, NonZeroI128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU8, NonZeroIsize, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU16, NonZeroI32, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU16, NonZeroI64, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU16, NonZeroI128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU32, NonZeroI64, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU32, NonZeroI128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } +nzint_impl_from! { NonZeroU64, NonZeroI128, #[unstable(feature = "lossless_non_zero_int_conv", issue = "66196")] } |