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Diffstat (limited to 'vendor/num-traits/src/bounds.rs')
-rw-r--r-- | vendor/num-traits/src/bounds.rs | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/vendor/num-traits/src/bounds.rs b/vendor/num-traits/src/bounds.rs new file mode 100644 index 0000000..acc990e --- /dev/null +++ b/vendor/num-traits/src/bounds.rs @@ -0,0 +1,148 @@ +use core::num::Wrapping; +use core::{f32, f64}; +use core::{i128, i16, i32, i64, i8, isize}; +use core::{u128, u16, u32, u64, u8, usize}; + +/// Numbers which have upper and lower bounds +pub trait Bounded { + // FIXME (#5527): These should be associated constants + /// Returns the smallest finite number this type can represent + fn min_value() -> Self; + /// Returns the largest finite number this type can represent + fn max_value() -> Self; +} + +/// Numbers which have lower bounds +pub trait LowerBounded { + /// Returns the smallest finite number this type can represent + fn min_value() -> Self; +} + +// FIXME: With a major version bump, this should be a supertrait instead +impl<T: Bounded> LowerBounded for T { + fn min_value() -> T { + Bounded::min_value() + } +} + +/// Numbers which have upper bounds +pub trait UpperBounded { + /// Returns the largest finite number this type can represent + fn max_value() -> Self; +} + +// FIXME: With a major version bump, this should be a supertrait instead +impl<T: Bounded> UpperBounded for T { + fn max_value() -> T { + Bounded::max_value() + } +} + +macro_rules! bounded_impl { + ($t:ty, $min:expr, $max:expr) => { + impl Bounded for $t { + #[inline] + fn min_value() -> $t { + $min + } + + #[inline] + fn max_value() -> $t { + $max + } + } + }; +} + +bounded_impl!(usize, usize::MIN, usize::MAX); +bounded_impl!(u8, u8::MIN, u8::MAX); +bounded_impl!(u16, u16::MIN, u16::MAX); +bounded_impl!(u32, u32::MIN, u32::MAX); +bounded_impl!(u64, u64::MIN, u64::MAX); +bounded_impl!(u128, u128::MIN, u128::MAX); + +bounded_impl!(isize, isize::MIN, isize::MAX); +bounded_impl!(i8, i8::MIN, i8::MAX); +bounded_impl!(i16, i16::MIN, i16::MAX); +bounded_impl!(i32, i32::MIN, i32::MAX); +bounded_impl!(i64, i64::MIN, i64::MAX); +bounded_impl!(i128, i128::MIN, i128::MAX); + +impl<T: Bounded> Bounded for Wrapping<T> { + fn min_value() -> Self { + Wrapping(T::min_value()) + } + fn max_value() -> Self { + Wrapping(T::max_value()) + } +} + +bounded_impl!(f32, f32::MIN, f32::MAX); + +macro_rules! for_each_tuple_ { + ( $m:ident !! ) => ( + $m! { } + ); + ( $m:ident !! $h:ident, $($t:ident,)* ) => ( + $m! { $h $($t)* } + for_each_tuple_! { $m !! $($t,)* } + ); +} +macro_rules! for_each_tuple { + ($m:ident) => { + for_each_tuple_! { $m !! A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, } + }; +} + +macro_rules! bounded_tuple { + ( $($name:ident)* ) => ( + impl<$($name: Bounded,)*> Bounded for ($($name,)*) { + #[inline] + fn min_value() -> Self { + ($($name::min_value(),)*) + } + #[inline] + fn max_value() -> Self { + ($($name::max_value(),)*) + } + } + ); +} + +for_each_tuple!(bounded_tuple); +bounded_impl!(f64, f64::MIN, f64::MAX); + +#[test] +fn wrapping_bounded() { + macro_rules! test_wrapping_bounded { + ($($t:ty)+) => { + $( + assert_eq!(<Wrapping<$t> as Bounded>::min_value().0, <$t>::min_value()); + assert_eq!(<Wrapping<$t> as Bounded>::max_value().0, <$t>::max_value()); + )+ + }; + } + + test_wrapping_bounded!(usize u8 u16 u32 u64 isize i8 i16 i32 i64); +} + +#[test] +fn wrapping_bounded_i128() { + macro_rules! test_wrapping_bounded { + ($($t:ty)+) => { + $( + assert_eq!(<Wrapping<$t> as Bounded>::min_value().0, <$t>::min_value()); + assert_eq!(<Wrapping<$t> as Bounded>::max_value().0, <$t>::max_value()); + )+ + }; + } + + test_wrapping_bounded!(u128 i128); +} + +#[test] +fn wrapping_is_bounded() { + fn require_bounded<T: Bounded>(_: &T) {} + require_bounded(&Wrapping(42_u32)); + require_bounded(&Wrapping(-42)); +} |