diff options
Diffstat (limited to 'library/core/src/cmp.rs')
| -rw-r--r-- | library/core/src/cmp.rs | 162 |
1 files changed, 111 insertions, 51 deletions
diff --git a/library/core/src/cmp.rs b/library/core/src/cmp.rs index 0812322f3fb..94536f25b41 100644 --- a/library/core/src/cmp.rs +++ b/library/core/src/cmp.rs @@ -29,7 +29,7 @@ mod bytewise; pub(crate) use bytewise::BytewiseEq; use self::Ordering::*; -use crate::marker::PointeeSized; +use crate::marker::{Destruct, PointeeSized}; use crate::ops::ControlFlow; /// Trait for comparisons using the equality operator. @@ -334,7 +334,9 @@ pub macro PartialEq($item:item) { #[doc(alias = "!=")] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_diagnostic_item = "Eq"] -pub trait Eq: PartialEq<Self> + PointeeSized { +#[const_trait] +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub trait Eq: [const] PartialEq<Self> + PointeeSized { // this method is used solely by `impl Eq or #[derive(Eq)]` to assert that every component of a // type implements `Eq` itself. The current deriving infrastructure means doing this assertion // without using a method on this trait is nearly impossible. @@ -380,8 +382,8 @@ pub struct AssertParamIsEq<T: Eq + PointeeSized> { /// /// assert_eq!(2.cmp(&1), Ordering::Greater); /// ``` -#[derive(Clone, Copy, Eq, PartialOrd, Ord, Debug, Hash)] -#[derive_const(PartialEq)] +#[derive(Copy, Debug, Hash)] +#[derive_const(Clone, Eq, PartialOrd, Ord, PartialEq)] #[stable(feature = "rust1", since = "1.0.0")] // This is a lang item only so that `BinOp::Cmp` in MIR can return it. // It has no special behavior, but does require that the three variants @@ -635,7 +637,11 @@ impl Ordering { #[inline] #[must_use] #[stable(feature = "ordering_chaining", since = "1.17.0")] - pub fn then_with<F: FnOnce() -> Ordering>(self, f: F) -> Ordering { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + pub const fn then_with<F>(self, f: F) -> Ordering + where + F: [const] FnOnce() -> Ordering + [const] Destruct, + { match self { Equal => f(), _ => self, @@ -659,13 +665,15 @@ impl Ordering { /// v.sort_by_key(|&num| (num > 3, Reverse(num))); /// assert_eq!(v, vec![3, 2, 1, 6, 5, 4]); /// ``` -#[derive(PartialEq, Eq, Debug, Copy, Default, Hash)] +#[derive(Copy, Debug, Hash)] +#[derive_const(PartialEq, Eq, Default)] #[stable(feature = "reverse_cmp_key", since = "1.19.0")] #[repr(transparent)] pub struct Reverse<T>(#[stable(feature = "reverse_cmp_key", since = "1.19.0")] pub T); #[stable(feature = "reverse_cmp_key", since = "1.19.0")] -impl<T: PartialOrd> PartialOrd for Reverse<T> { +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +impl<T: [const] PartialOrd> const PartialOrd for Reverse<T> { #[inline] fn partial_cmp(&self, other: &Reverse<T>) -> Option<Ordering> { other.0.partial_cmp(&self.0) @@ -690,7 +698,8 @@ impl<T: PartialOrd> PartialOrd for Reverse<T> { } #[stable(feature = "reverse_cmp_key", since = "1.19.0")] -impl<T: Ord> Ord for Reverse<T> { +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +impl<T: [const] Ord> const Ord for Reverse<T> { #[inline] fn cmp(&self, other: &Reverse<T>) -> Ordering { other.0.cmp(&self.0) @@ -957,7 +966,9 @@ impl<T: Clone> Clone for Reverse<T> { #[doc(alias = ">=")] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_diagnostic_item = "Ord"] -pub trait Ord: Eq + PartialOrd<Self> + PointeeSized { +#[const_trait] +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub trait Ord: [const] Eq + [const] PartialOrd<Self> + PointeeSized { /// This method returns an [`Ordering`] between `self` and `other`. /// /// By convention, `self.cmp(&other)` returns the ordering matching the expression @@ -1011,7 +1022,7 @@ pub trait Ord: Eq + PartialOrd<Self> + PointeeSized { #[rustc_diagnostic_item = "cmp_ord_max"] fn max(self, other: Self) -> Self where - Self: Sized, + Self: Sized + [const] Destruct, { if other < self { self } else { other } } @@ -1050,7 +1061,7 @@ pub trait Ord: Eq + PartialOrd<Self> + PointeeSized { #[rustc_diagnostic_item = "cmp_ord_min"] fn min(self, other: Self) -> Self where - Self: Sized, + Self: Sized + [const] Destruct, { if other < self { other } else { self } } @@ -1076,7 +1087,7 @@ pub trait Ord: Eq + PartialOrd<Self> + PointeeSized { #[stable(feature = "clamp", since = "1.50.0")] fn clamp(self, min: Self, max: Self) -> Self where - Self: Sized, + Self: Sized + [const] Destruct, { assert!(min <= max); if self < min { @@ -1341,6 +1352,8 @@ pub macro Ord($item:item) { )] #[rustc_diagnostic_item = "PartialOrd"] #[allow(multiple_supertrait_upcastable)] // FIXME(sized_hierarchy): remove this +#[const_trait] +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] pub trait PartialOrd<Rhs: PointeeSized = Self>: PartialEq<Rhs> + PointeeSized { /// This method returns an ordering between `self` and `other` values if one exists. /// @@ -1481,13 +1494,14 @@ pub trait PartialOrd<Rhs: PointeeSized = Self>: PartialEq<Rhs> + PointeeSized { } } -fn default_chaining_impl<T, U>( +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +const fn default_chaining_impl<T, U>( lhs: &T, rhs: &U, - p: impl FnOnce(Ordering) -> bool, + p: impl [const] FnOnce(Ordering) -> bool + [const] Destruct, ) -> ControlFlow<bool> where - T: PartialOrd<U> + PointeeSized, + T: [const] PartialOrd<U> + PointeeSized, U: PointeeSized, { // It's important that this only call `partial_cmp` once, not call `eq` then @@ -1545,7 +1559,8 @@ pub macro PartialOrd($item:item) { #[must_use] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_diagnostic_item = "cmp_min"] -pub fn min<T: Ord>(v1: T, v2: T) -> T { +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub const fn min<T: [const] Ord + [const] Destruct>(v1: T, v2: T) -> T { v1.min(v2) } @@ -1575,7 +1590,12 @@ pub fn min<T: Ord>(v1: T, v2: T) -> T { #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] -pub fn min_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub const fn min_by<T: [const] Destruct, F: [const] FnOnce(&T, &T) -> Ordering>( + v1: T, + v2: T, + compare: F, +) -> T { if compare(&v1, &v2).is_le() { v1 } else { v2 } } @@ -1600,7 +1620,13 @@ pub fn min_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] -pub fn min_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub const fn min_by_key<T, F, K>(v1: T, v2: T, mut f: F) -> T +where + T: [const] Destruct, + F: [const] FnMut(&T) -> K + [const] Destruct, + K: [const] Ord + [const] Destruct, +{ if f(&v2) < f(&v1) { v2 } else { v1 } } @@ -1640,7 +1666,8 @@ pub fn min_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { #[must_use] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_diagnostic_item = "cmp_max"] -pub fn max<T: Ord>(v1: T, v2: T) -> T { +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub const fn max<T: [const] Ord + [const] Destruct>(v1: T, v2: T) -> T { v1.max(v2) } @@ -1670,7 +1697,12 @@ pub fn max<T: Ord>(v1: T, v2: T) -> T { #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] -pub fn max_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub const fn max_by<T: [const] Destruct, F: [const] FnOnce(&T, &T) -> Ordering>( + v1: T, + v2: T, + compare: F, +) -> T { if compare(&v1, &v2).is_gt() { v1 } else { v2 } } @@ -1695,7 +1727,13 @@ pub fn max_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] -pub fn max_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub const fn max_by_key<T, F, K>(v1: T, v2: T, mut f: F) -> T +where + T: [const] Destruct, + F: [const] FnMut(&T) -> K + [const] Destruct, + K: [const] Ord + [const] Destruct, +{ if f(&v2) < f(&v1) { v1 } else { v2 } } @@ -1739,9 +1777,10 @@ pub fn max_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { #[inline] #[must_use] #[unstable(feature = "cmp_minmax", issue = "115939")] -pub fn minmax<T>(v1: T, v2: T) -> [T; 2] +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub const fn minmax<T>(v1: T, v2: T) -> [T; 2] where - T: Ord, + T: [const] Ord, { if v2 < v1 { [v2, v1] } else { [v1, v2] } } @@ -1773,9 +1812,10 @@ where #[inline] #[must_use] #[unstable(feature = "cmp_minmax", issue = "115939")] -pub fn minmax_by<T, F>(v1: T, v2: T, compare: F) -> [T; 2] +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub const fn minmax_by<T, F>(v1: T, v2: T, compare: F) -> [T; 2] where - F: FnOnce(&T, &T) -> Ordering, + F: [const] FnOnce(&T, &T) -> Ordering, { if compare(&v1, &v2).is_le() { [v1, v2] } else { [v2, v1] } } @@ -1801,10 +1841,11 @@ where #[inline] #[must_use] #[unstable(feature = "cmp_minmax", issue = "115939")] -pub fn minmax_by_key<T, F, K>(v1: T, v2: T, mut f: F) -> [T; 2] +#[rustc_const_unstable(feature = "const_cmp", issue = "143800")] +pub const fn minmax_by_key<T, F, K>(v1: T, v2: T, mut f: F) -> [T; 2] where - F: FnMut(&T) -> K, - K: Ord, + F: [const] FnMut(&T) -> K + [const] Destruct, + K: [const] Ord + [const] Destruct, { if f(&v2) < f(&v1) { [v2, v1] } else { [v1, v2] } } @@ -1830,7 +1871,8 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl PartialEq for () { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const PartialEq for () { #[inline] fn eq(&self, _other: &()) -> bool { true @@ -1848,7 +1890,8 @@ mod impls { macro_rules! eq_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - impl Eq for $t {} + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const Eq for $t {} )*) } @@ -1896,7 +1939,8 @@ mod impls { macro_rules! partial_ord_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - impl PartialOrd for $t { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const PartialOrd for $t { #[inline] fn partial_cmp(&self, other: &Self) -> Option<Ordering> { match (*self <= *other, *self >= *other) { @@ -1913,7 +1957,8 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl PartialOrd for () { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const PartialOrd for () { #[inline] fn partial_cmp(&self, _: &()) -> Option<Ordering> { Some(Equal) @@ -1921,7 +1966,8 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl PartialOrd for bool { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const PartialOrd for bool { #[inline] fn partial_cmp(&self, other: &bool) -> Option<Ordering> { Some(self.cmp(other)) @@ -1935,7 +1981,8 @@ mod impls { macro_rules! ord_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - impl PartialOrd for $t { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const PartialOrd for $t { #[inline] fn partial_cmp(&self, other: &Self) -> Option<Ordering> { Some(crate::intrinsics::three_way_compare(*self, *other)) @@ -1945,7 +1992,8 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl Ord for $t { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const Ord for $t { #[inline] fn cmp(&self, other: &Self) -> Ordering { crate::intrinsics::three_way_compare(*self, *other) @@ -1955,7 +2003,8 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl Ord for () { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const Ord for () { #[inline] fn cmp(&self, _other: &()) -> Ordering { Equal @@ -1963,7 +2012,8 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - impl Ord for bool { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const Ord for bool { #[inline] fn cmp(&self, other: &bool) -> Ordering { // Casting to i8's and converting the difference to an Ordering generates @@ -1998,7 +2048,8 @@ mod impls { ord_impl! { char usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 } #[unstable(feature = "never_type", issue = "35121")] - impl PartialEq for ! { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const PartialEq for ! { #[inline] fn eq(&self, _: &!) -> bool { *self @@ -2006,10 +2057,12 @@ mod impls { } #[unstable(feature = "never_type", issue = "35121")] - impl Eq for ! {} + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const Eq for ! {} #[unstable(feature = "never_type", issue = "35121")] - impl PartialOrd for ! { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const PartialOrd for ! { #[inline] fn partial_cmp(&self, _: &!) -> Option<Ordering> { *self @@ -2017,7 +2070,8 @@ mod impls { } #[unstable(feature = "never_type", issue = "35121")] - impl Ord for ! { + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl const Ord for ! { #[inline] fn cmp(&self, _: &!) -> Ordering { *self @@ -2042,9 +2096,10 @@ mod impls { } } #[stable(feature = "rust1", since = "1.0.0")] - impl<A: PointeeSized, B: PointeeSized> PartialOrd<&B> for &A + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl<A: PointeeSized, B: PointeeSized> const PartialOrd<&B> for &A where - A: PartialOrd<B>, + A: [const] PartialOrd<B>, { #[inline] fn partial_cmp(&self, other: &&B) -> Option<Ordering> { @@ -2084,9 +2139,10 @@ mod impls { } } #[stable(feature = "rust1", since = "1.0.0")] - impl<A: PointeeSized> Ord for &A + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl<A: PointeeSized> const Ord for &A where - A: Ord, + A: [const] Ord, { #[inline] fn cmp(&self, other: &Self) -> Ordering { @@ -2094,7 +2150,8 @@ mod impls { } } #[stable(feature = "rust1", since = "1.0.0")] - impl<A: PointeeSized> Eq for &A where A: Eq {} + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl<A: PointeeSized> const Eq for &A where A: [const] Eq {} // &mut pointers @@ -2114,9 +2171,10 @@ mod impls { } } #[stable(feature = "rust1", since = "1.0.0")] - impl<A: PointeeSized, B: PointeeSized> PartialOrd<&mut B> for &mut A + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl<A: PointeeSized, B: PointeeSized> const PartialOrd<&mut B> for &mut A where - A: PartialOrd<B>, + A: [const] PartialOrd<B>, { #[inline] fn partial_cmp(&self, other: &&mut B) -> Option<Ordering> { @@ -2156,9 +2214,10 @@ mod impls { } } #[stable(feature = "rust1", since = "1.0.0")] - impl<A: PointeeSized> Ord for &mut A + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl<A: PointeeSized> const Ord for &mut A where - A: Ord, + A: [const] Ord, { #[inline] fn cmp(&self, other: &Self) -> Ordering { @@ -2166,7 +2225,8 @@ mod impls { } } #[stable(feature = "rust1", since = "1.0.0")] - impl<A: PointeeSized> Eq for &mut A where A: Eq {} + #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] + impl<A: PointeeSized> const Eq for &mut A where A: [const] Eq {} #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_unstable(feature = "const_cmp", issue = "143800")] |