1 // Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! Functionality for ordering and comparison.
13 //! This module defines both [`PartialOrd`] and [`PartialEq`] traits which are used
14 //! by the compiler to implement comparison operators. Rust programs may
15 //! implement [`PartialOrd`] to overload the `<`, `<=`, `>`, and `>=` operators,
16 //! and may implement [`PartialEq`] to overload the `==` and `!=` operators.
18 //! [`PartialOrd`]: trait.PartialOrd.html
19 //! [`PartialEq`]: trait.PartialEq.html
27 //! // these two lines are equivalent
28 //! assert_eq!(x < y, true);
29 //! assert_eq!(x.lt(&y), true);
31 //! // these two lines are also equivalent
32 //! assert_eq!(x == y, false);
33 //! assert_eq!(x.eq(&y), false);
36 #![stable(feature = "rust1", since = "1.0.0")]
38 use self::Ordering::*;
40 /// Trait for equality comparisons which are [partial equivalence
41 /// relations](http://en.wikipedia.org/wiki/Partial_equivalence_relation).
43 /// This trait allows for partial equality, for types that do not have a full
44 /// equivalence relation. For example, in floating point numbers `NaN != NaN`,
45 /// so floating point types implement `PartialEq` but not `Eq`.
47 /// Formally, the equality must be (for all `a`, `b` and `c`):
49 /// - symmetric: `a == b` implies `b == a`; and
50 /// - transitive: `a == b` and `b == c` implies `a == c`.
52 /// Note that these requirements mean that the trait itself must be implemented
53 /// symmetrically and transitively: if `T: PartialEq<U>` and `U: PartialEq<V>`
54 /// then `U: PartialEq<T>` and `T: PartialEq<V>`.
58 /// This trait can be used with `#[derive]`. When `derive`d on structs, two
59 /// instances are equal if all fields are equal, and not equal if any fields
60 /// are not equal. When `derive`d on enums, each variant is equal to itself
61 /// and not equal to the other variants.
63 /// ## How can I implement `PartialEq`?
65 /// PartialEq only requires the `eq` method to be implemented; `ne` is defined
66 /// in terms of it by default. Any manual implementation of `ne` *must* respect
67 /// the rule that `eq` is a strict inverse of `ne`; that is, `!(a == b)` if and
70 /// An example implementation for a domain in which two books are considered
71 /// the same book if their ISBN matches, even if the formats differ:
74 /// enum BookFormat { Paperback, Hardback, Ebook }
77 /// format: BookFormat,
80 /// impl PartialEq for Book {
81 /// fn eq(&self, other: &Book) -> bool {
82 /// self.isbn == other.isbn
86 /// let b1 = Book { isbn: 3, format: BookFormat::Paperback };
87 /// let b2 = Book { isbn: 3, format: BookFormat::Ebook };
88 /// let b3 = Book { isbn: 10, format: BookFormat::Paperback };
90 /// assert!(b1 == b2);
91 /// assert!(b1 != b3);
100 /// assert_eq!(x == y, false);
101 /// assert_eq!(x.eq(&y), false);
104 #[stable(feature = "rust1", since = "1.0.0")]
105 #[rustc_on_unimplemented = "can't compare `{Self}` with `{Rhs}`"]
106 pub trait PartialEq<Rhs: ?Sized = Self> {
107 /// This method tests for `self` and `other` values to be equal, and is used
109 #[stable(feature = "rust1", since = "1.0.0")]
110 fn eq(&self, other: &Rhs) -> bool;
112 /// This method tests for `!=`.
114 #[stable(feature = "rust1", since = "1.0.0")]
115 fn ne(&self, other: &Rhs) -> bool { !self.eq(other) }
118 /// Trait for equality comparisons which are [equivalence relations](
119 /// https://en.wikipedia.org/wiki/Equivalence_relation).
121 /// This means, that in addition to `a == b` and `a != b` being strict inverses, the equality must
122 /// be (for all `a`, `b` and `c`):
124 /// - reflexive: `a == a`;
125 /// - symmetric: `a == b` implies `b == a`; and
126 /// - transitive: `a == b` and `b == c` implies `a == c`.
128 /// This property cannot be checked by the compiler, and therefore `Eq` implies
129 /// `PartialEq`, and has no extra methods.
133 /// This trait can be used with `#[derive]`. When `derive`d, because `Eq` has
134 /// no extra methods, it is only informing the compiler that this is an
135 /// equivalence relation rather than a partial equivalence relation. Note that
136 /// the `derive` strategy requires all fields are `Eq`, which isn't
139 /// ## How can I implement `Eq`?
141 /// If you cannot use the `derive` strategy, specify that your type implements
142 /// `Eq`, which has no methods:
145 /// enum BookFormat { Paperback, Hardback, Ebook }
148 /// format: BookFormat,
150 /// impl PartialEq for Book {
151 /// fn eq(&self, other: &Book) -> bool {
152 /// self.isbn == other.isbn
155 /// impl Eq for Book {}
157 #[stable(feature = "rust1", since = "1.0.0")]
158 pub trait Eq: PartialEq<Self> {
159 // FIXME #13101: this method is used solely by #[deriving] to
160 // assert that every component of a type implements #[deriving]
161 // itself, the current deriving infrastructure means doing this
162 // assertion without using a method on this trait is nearly
165 // This should never be implemented by hand.
168 #[stable(feature = "rust1", since = "1.0.0")]
169 fn assert_receiver_is_total_eq(&self) {}
172 // FIXME: this struct is used solely by #[derive] to
173 // assert that every component of a type implements Eq.
175 // This struct should never appear in user code.
177 #[allow(missing_debug_implementations)]
178 #[unstable(feature = "derive_eq",
179 reason = "deriving hack, should not be public",
181 pub struct AssertParamIsEq<T: Eq + ?Sized> { _field: ::marker::PhantomData<T> }
183 /// An `Ordering` is the result of a comparison between two values.
188 /// use std::cmp::Ordering;
190 /// let result = 1.cmp(&2);
191 /// assert_eq!(Ordering::Less, result);
193 /// let result = 1.cmp(&1);
194 /// assert_eq!(Ordering::Equal, result);
196 /// let result = 2.cmp(&1);
197 /// assert_eq!(Ordering::Greater, result);
199 #[derive(Clone, Copy, PartialEq, Debug, Hash)]
200 #[stable(feature = "rust1", since = "1.0.0")]
202 /// An ordering where a compared value is less [than another].
203 #[stable(feature = "rust1", since = "1.0.0")]
205 /// An ordering where a compared value is equal [to another].
206 #[stable(feature = "rust1", since = "1.0.0")]
208 /// An ordering where a compared value is greater [than another].
209 #[stable(feature = "rust1", since = "1.0.0")]
214 /// Reverses the `Ordering`.
216 /// * `Less` becomes `Greater`.
217 /// * `Greater` becomes `Less`.
218 /// * `Equal` becomes `Equal`.
225 /// use std::cmp::Ordering;
227 /// assert_eq!(Ordering::Less.reverse(), Ordering::Greater);
228 /// assert_eq!(Ordering::Equal.reverse(), Ordering::Equal);
229 /// assert_eq!(Ordering::Greater.reverse(), Ordering::Less);
232 /// This method can be used to reverse a comparison:
235 /// let mut data: &mut [_] = &mut [2, 10, 5, 8];
237 /// // sort the array from largest to smallest.
238 /// data.sort_by(|a, b| a.cmp(b).reverse());
240 /// let b: &mut [_] = &mut [10, 8, 5, 2];
241 /// assert!(data == b);
244 #[stable(feature = "rust1", since = "1.0.0")]
245 pub fn reverse(self) -> Ordering {
253 /// Chains two orderings.
255 /// Returns `self` when it's not `Equal`. Otherwise returns `other`.
259 /// use std::cmp::Ordering;
261 /// let result = Ordering::Equal.then(Ordering::Less);
262 /// assert_eq!(result, Ordering::Less);
264 /// let result = Ordering::Less.then(Ordering::Equal);
265 /// assert_eq!(result, Ordering::Less);
267 /// let result = Ordering::Less.then(Ordering::Greater);
268 /// assert_eq!(result, Ordering::Less);
270 /// let result = Ordering::Equal.then(Ordering::Equal);
271 /// assert_eq!(result, Ordering::Equal);
273 /// let x: (i64, i64, i64) = (1, 2, 7);
274 /// let y: (i64, i64, i64) = (1, 5, 3);
275 /// let result = x.0.cmp(&y.0).then(x.1.cmp(&y.1)).then(x.2.cmp(&y.2));
277 /// assert_eq!(result, Ordering::Less);
280 #[stable(feature = "ordering_chaining", since = "1.17.0")]
281 pub fn then(self, other: Ordering) -> Ordering {
288 /// Chains the ordering with the given function.
290 /// Returns `self` when it's not `Equal`. Otherwise calls `f` and returns
296 /// use std::cmp::Ordering;
298 /// let result = Ordering::Equal.then_with(|| Ordering::Less);
299 /// assert_eq!(result, Ordering::Less);
301 /// let result = Ordering::Less.then_with(|| Ordering::Equal);
302 /// assert_eq!(result, Ordering::Less);
304 /// let result = Ordering::Less.then_with(|| Ordering::Greater);
305 /// assert_eq!(result, Ordering::Less);
307 /// let result = Ordering::Equal.then_with(|| Ordering::Equal);
308 /// assert_eq!(result, Ordering::Equal);
310 /// let x: (i64, i64, i64) = (1, 2, 7);
311 /// let y: (i64, i64, i64) = (1, 5, 3);
312 /// let result = x.0.cmp(&y.0).then_with(|| x.1.cmp(&y.1)).then_with(|| x.2.cmp(&y.2));
314 /// assert_eq!(result, Ordering::Less);
317 #[stable(feature = "ordering_chaining", since = "1.17.0")]
318 pub fn then_with<F: FnOnce() -> Ordering>(self, f: F) -> Ordering {
326 /// A helper struct for reverse ordering.
328 /// This struct is a helper to be used with functions like `Vec::sort_by_key` and
329 /// can be used to reverse order a part of a key.
334 /// #![feature(reverse_cmp_key)]
335 /// use std::cmp::Reverse;
337 /// let mut v = vec![1, 2, 3, 4, 5, 6];
338 /// v.sort_by_key(|&num| (num > 3, Reverse(num)));
339 /// assert_eq!(v, vec![3, 2, 1, 6, 5, 4]);
341 #[derive(PartialEq, Eq, Debug)]
342 #[unstable(feature = "reverse_cmp_key", issue = "40893")]
343 pub struct Reverse<T>(pub T);
345 #[unstable(feature = "reverse_cmp_key", issue = "40893")]
346 impl<T: PartialOrd> PartialOrd for Reverse<T> {
348 fn partial_cmp(&self, other: &Reverse<T>) -> Option<Ordering> {
349 other.0.partial_cmp(&self.0)
353 fn lt(&self, other: &Self) -> bool { other.0 < self.0 }
355 fn le(&self, other: &Self) -> bool { other.0 <= self.0 }
357 fn ge(&self, other: &Self) -> bool { other.0 >= self.0 }
359 fn gt(&self, other: &Self) -> bool { other.0 > self.0 }
362 #[unstable(feature = "reverse_cmp_key", issue = "40893")]
363 impl<T: Ord> Ord for Reverse<T> {
365 fn cmp(&self, other: &Reverse<T>) -> Ordering {
370 /// Trait for types that form a [total order](https://en.wikipedia.org/wiki/Total_order).
372 /// An order is a total order if it is (for all `a`, `b` and `c`):
374 /// - total and antisymmetric: exactly one of `a < b`, `a == b` or `a > b` is true; and
375 /// - transitive, `a < b` and `b < c` implies `a < c`. The same must hold for both `==` and `>`.
379 /// This trait can be used with `#[derive]`. When `derive`d, it will produce a lexicographic
380 /// ordering based on the top-to-bottom declaration order of the struct's members.
382 /// ## How can I implement `Ord`?
384 /// `Ord` requires that the type also be `PartialOrd` and `Eq` (which requires `PartialEq`).
386 /// Then you must define an implementation for `cmp()`. You may find it useful to use
387 /// `cmp()` on your type's fields.
389 /// Here's an example where you want to sort people by height only, disregarding `id`
393 /// use std::cmp::Ordering;
402 /// impl Ord for Person {
403 /// fn cmp(&self, other: &Person) -> Ordering {
404 /// self.height.cmp(&other.height)
408 /// impl PartialOrd for Person {
409 /// fn partial_cmp(&self, other: &Person) -> Option<Ordering> {
410 /// Some(self.cmp(other))
414 /// impl PartialEq for Person {
415 /// fn eq(&self, other: &Person) -> bool {
416 /// self.height == other.height
420 #[stable(feature = "rust1", since = "1.0.0")]
421 pub trait Ord: Eq + PartialOrd<Self> {
422 /// This method returns an `Ordering` between `self` and `other`.
424 /// By convention, `self.cmp(&other)` returns the ordering matching the expression
425 /// `self <operator> other` if true.
430 /// use std::cmp::Ordering;
432 /// assert_eq!(5.cmp(&10), Ordering::Less);
433 /// assert_eq!(10.cmp(&5), Ordering::Greater);
434 /// assert_eq!(5.cmp(&5), Ordering::Equal);
436 #[stable(feature = "rust1", since = "1.0.0")]
437 fn cmp(&self, other: &Self) -> Ordering;
440 #[stable(feature = "rust1", since = "1.0.0")]
441 impl Eq for Ordering {}
443 #[stable(feature = "rust1", since = "1.0.0")]
444 impl Ord for Ordering {
446 fn cmp(&self, other: &Ordering) -> Ordering {
447 (*self as i32).cmp(&(*other as i32))
451 #[stable(feature = "rust1", since = "1.0.0")]
452 impl PartialOrd for Ordering {
454 fn partial_cmp(&self, other: &Ordering) -> Option<Ordering> {
455 (*self as i32).partial_cmp(&(*other as i32))
459 /// Trait for values that can be compared for a sort-order.
461 /// The comparison must satisfy, for all `a`, `b` and `c`:
463 /// - antisymmetry: if `a < b` then `!(a > b)`, as well as `a > b` implying `!(a < b)`; and
464 /// - transitivity: `a < b` and `b < c` implies `a < c`. The same must hold for both `==` and `>`.
466 /// Note that these requirements mean that the trait itself must be implemented symmetrically and
467 /// transitively: if `T: PartialOrd<U>` and `U: PartialOrd<V>` then `U: PartialOrd<T>` and `T:
472 /// This trait can be used with `#[derive]`. When `derive`d, it will produce a lexicographic
473 /// ordering based on the top-to-bottom declaration order of the struct's members.
475 /// ## How can I implement `PartialOrd`?
477 /// PartialOrd only requires implementation of the `partial_cmp` method, with the others generated
478 /// from default implementations.
480 /// However it remains possible to implement the others separately for types which do not have a
481 /// total order. For example, for floating point numbers, `NaN < 0 == false` and `NaN >= 0 ==
482 /// false` (cf. IEEE 754-2008 section 5.11).
484 /// `PartialOrd` requires your type to be `PartialEq`.
486 /// If your type is `Ord`, you can implement `partial_cmp()` by using `cmp()`:
489 /// use std::cmp::Ordering;
498 /// impl PartialOrd for Person {
499 /// fn partial_cmp(&self, other: &Person) -> Option<Ordering> {
500 /// Some(self.cmp(other))
504 /// impl Ord for Person {
505 /// fn cmp(&self, other: &Person) -> Ordering {
506 /// self.height.cmp(&other.height)
510 /// impl PartialEq for Person {
511 /// fn eq(&self, other: &Person) -> bool {
512 /// self.height == other.height
517 /// You may also find it useful to use `partial_cmp()` on your type's fields. Here
518 /// is an example of `Person` types who have a floating-point `height` field that
519 /// is the only field to be used for sorting:
522 /// use std::cmp::Ordering;
530 /// impl PartialOrd for Person {
531 /// fn partial_cmp(&self, other: &Person) -> Option<Ordering> {
532 /// self.height.partial_cmp(&other.height)
536 /// impl PartialEq for Person {
537 /// fn eq(&self, other: &Person) -> bool {
538 /// self.height == other.height
549 /// assert_eq!(x < y, true);
550 /// assert_eq!(x.lt(&y), true);
553 #[stable(feature = "rust1", since = "1.0.0")]
554 #[rustc_on_unimplemented = "can't compare `{Self}` with `{Rhs}`"]
555 pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> {
556 /// This method returns an ordering between `self` and `other` values if one exists.
561 /// use std::cmp::Ordering;
563 /// let result = 1.0.partial_cmp(&2.0);
564 /// assert_eq!(result, Some(Ordering::Less));
566 /// let result = 1.0.partial_cmp(&1.0);
567 /// assert_eq!(result, Some(Ordering::Equal));
569 /// let result = 2.0.partial_cmp(&1.0);
570 /// assert_eq!(result, Some(Ordering::Greater));
573 /// When comparison is impossible:
576 /// let result = std::f64::NAN.partial_cmp(&1.0);
577 /// assert_eq!(result, None);
579 #[stable(feature = "rust1", since = "1.0.0")]
580 fn partial_cmp(&self, other: &Rhs) -> Option<Ordering>;
582 /// This method tests less than (for `self` and `other`) and is used by the `<` operator.
587 /// let result = 1.0 < 2.0;
588 /// assert_eq!(result, true);
590 /// let result = 2.0 < 1.0;
591 /// assert_eq!(result, false);
594 #[stable(feature = "rust1", since = "1.0.0")]
595 fn lt(&self, other: &Rhs) -> bool {
596 match self.partial_cmp(other) {
602 /// This method tests less than or equal to (for `self` and `other`) and is used by the `<=`
608 /// let result = 1.0 <= 2.0;
609 /// assert_eq!(result, true);
611 /// let result = 2.0 <= 2.0;
612 /// assert_eq!(result, true);
615 #[stable(feature = "rust1", since = "1.0.0")]
616 fn le(&self, other: &Rhs) -> bool {
617 match self.partial_cmp(other) {
618 Some(Less) | Some(Equal) => true,
623 /// This method tests greater than (for `self` and `other`) and is used by the `>` operator.
628 /// let result = 1.0 > 2.0;
629 /// assert_eq!(result, false);
631 /// let result = 2.0 > 2.0;
632 /// assert_eq!(result, false);
635 #[stable(feature = "rust1", since = "1.0.0")]
636 fn gt(&self, other: &Rhs) -> bool {
637 match self.partial_cmp(other) {
638 Some(Greater) => true,
643 /// This method tests greater than or equal to (for `self` and `other`) and is used by the `>=`
649 /// let result = 2.0 >= 1.0;
650 /// assert_eq!(result, true);
652 /// let result = 2.0 >= 2.0;
653 /// assert_eq!(result, true);
656 #[stable(feature = "rust1", since = "1.0.0")]
657 fn ge(&self, other: &Rhs) -> bool {
658 match self.partial_cmp(other) {
659 Some(Greater) | Some(Equal) => true,
665 /// Compares and returns the minimum of two values.
667 /// Returns the first argument if the comparison determines them to be equal.
674 /// assert_eq!(1, cmp::min(1, 2));
675 /// assert_eq!(2, cmp::min(2, 2));
678 #[stable(feature = "rust1", since = "1.0.0")]
679 pub fn min<T: Ord>(v1: T, v2: T) -> T {
680 if v1 <= v2 { v1 } else { v2 }
683 /// Compares and returns the maximum of two values.
685 /// Returns the second argument if the comparison determines them to be equal.
692 /// assert_eq!(2, cmp::max(1, 2));
693 /// assert_eq!(2, cmp::max(2, 2));
696 #[stable(feature = "rust1", since = "1.0.0")]
697 pub fn max<T: Ord>(v1: T, v2: T) -> T {
698 if v2 >= v1 { v2 } else { v1 }
701 // Implementation of PartialEq, Eq, PartialOrd and Ord for primitive types
703 use cmp::Ordering::{self, Less, Greater, Equal};
705 macro_rules! partial_eq_impl {
707 #[stable(feature = "rust1", since = "1.0.0")]
708 impl PartialEq for $t {
710 fn eq(&self, other: &$t) -> bool { (*self) == (*other) }
712 fn ne(&self, other: &$t) -> bool { (*self) != (*other) }
717 #[stable(feature = "rust1", since = "1.0.0")]
718 impl PartialEq for () {
720 fn eq(&self, _other: &()) -> bool { true }
722 fn ne(&self, _other: &()) -> bool { false }
726 bool char usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f32 f64
729 macro_rules! eq_impl {
731 #[stable(feature = "rust1", since = "1.0.0")]
736 eq_impl! { () bool char usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 }
738 macro_rules! partial_ord_impl {
740 #[stable(feature = "rust1", since = "1.0.0")]
741 impl PartialOrd for $t {
743 fn partial_cmp(&self, other: &$t) -> Option<Ordering> {
744 match (self <= other, self >= other) {
745 (false, false) => None,
746 (false, true) => Some(Greater),
747 (true, false) => Some(Less),
748 (true, true) => Some(Equal),
752 fn lt(&self, other: &$t) -> bool { (*self) < (*other) }
754 fn le(&self, other: &$t) -> bool { (*self) <= (*other) }
756 fn ge(&self, other: &$t) -> bool { (*self) >= (*other) }
758 fn gt(&self, other: &$t) -> bool { (*self) > (*other) }
763 #[stable(feature = "rust1", since = "1.0.0")]
764 impl PartialOrd for () {
766 fn partial_cmp(&self, _: &()) -> Option<Ordering> {
771 #[stable(feature = "rust1", since = "1.0.0")]
772 impl PartialOrd for bool {
774 fn partial_cmp(&self, other: &bool) -> Option<Ordering> {
775 (*self as u8).partial_cmp(&(*other as u8))
779 partial_ord_impl! { f32 f64 }
781 macro_rules! ord_impl {
783 #[stable(feature = "rust1", since = "1.0.0")]
784 impl PartialOrd for $t {
786 fn partial_cmp(&self, other: &$t) -> Option<Ordering> {
787 Some(self.cmp(other))
790 fn lt(&self, other: &$t) -> bool { (*self) < (*other) }
792 fn le(&self, other: &$t) -> bool { (*self) <= (*other) }
794 fn ge(&self, other: &$t) -> bool { (*self) >= (*other) }
796 fn gt(&self, other: &$t) -> bool { (*self) > (*other) }
799 #[stable(feature = "rust1", since = "1.0.0")]
802 fn cmp(&self, other: &$t) -> Ordering {
803 if *self == *other { Equal }
804 else if *self < *other { Less }
811 #[stable(feature = "rust1", since = "1.0.0")]
814 fn cmp(&self, _other: &()) -> Ordering { Equal }
817 #[stable(feature = "rust1", since = "1.0.0")]
820 fn cmp(&self, other: &bool) -> Ordering {
821 (*self as u8).cmp(&(*other as u8))
825 ord_impl! { char usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 }
827 #[unstable(feature = "never_type_impls", issue = "35121")]
828 impl PartialEq for ! {
829 fn eq(&self, _: &!) -> bool {
834 #[unstable(feature = "never_type_impls", issue = "35121")]
837 #[unstable(feature = "never_type_impls", issue = "35121")]
838 impl PartialOrd for ! {
839 fn partial_cmp(&self, _: &!) -> Option<Ordering> {
844 #[unstable(feature = "never_type_impls", issue = "35121")]
846 fn cmp(&self, _: &!) -> Ordering {
853 #[stable(feature = "rust1", since = "1.0.0")]
854 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b B> for &'a A where A: PartialEq<B> {
856 fn eq(&self, other: & &'b B) -> bool { PartialEq::eq(*self, *other) }
858 fn ne(&self, other: & &'b B) -> bool { PartialEq::ne(*self, *other) }
860 #[stable(feature = "rust1", since = "1.0.0")]
861 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialOrd<&'b B> for &'a A where A: PartialOrd<B> {
863 fn partial_cmp(&self, other: &&'b B) -> Option<Ordering> {
864 PartialOrd::partial_cmp(*self, *other)
867 fn lt(&self, other: & &'b B) -> bool { PartialOrd::lt(*self, *other) }
869 fn le(&self, other: & &'b B) -> bool { PartialOrd::le(*self, *other) }
871 fn ge(&self, other: & &'b B) -> bool { PartialOrd::ge(*self, *other) }
873 fn gt(&self, other: & &'b B) -> bool { PartialOrd::gt(*self, *other) }
875 #[stable(feature = "rust1", since = "1.0.0")]
876 impl<'a, A: ?Sized> Ord for &'a A where A: Ord {
878 fn cmp(&self, other: & &'a A) -> Ordering { Ord::cmp(*self, *other) }
880 #[stable(feature = "rust1", since = "1.0.0")]
881 impl<'a, A: ?Sized> Eq for &'a A where A: Eq {}
885 #[stable(feature = "rust1", since = "1.0.0")]
886 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b mut B> for &'a mut A where A: PartialEq<B> {
888 fn eq(&self, other: &&'b mut B) -> bool { PartialEq::eq(*self, *other) }
890 fn ne(&self, other: &&'b mut B) -> bool { PartialEq::ne(*self, *other) }
892 #[stable(feature = "rust1", since = "1.0.0")]
893 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialOrd<&'b mut B> for &'a mut A where A: PartialOrd<B> {
895 fn partial_cmp(&self, other: &&'b mut B) -> Option<Ordering> {
896 PartialOrd::partial_cmp(*self, *other)
899 fn lt(&self, other: &&'b mut B) -> bool { PartialOrd::lt(*self, *other) }
901 fn le(&self, other: &&'b mut B) -> bool { PartialOrd::le(*self, *other) }
903 fn ge(&self, other: &&'b mut B) -> bool { PartialOrd::ge(*self, *other) }
905 fn gt(&self, other: &&'b mut B) -> bool { PartialOrd::gt(*self, *other) }
907 #[stable(feature = "rust1", since = "1.0.0")]
908 impl<'a, A: ?Sized> Ord for &'a mut A where A: Ord {
910 fn cmp(&self, other: &&'a mut A) -> Ordering { Ord::cmp(*self, *other) }
912 #[stable(feature = "rust1", since = "1.0.0")]
913 impl<'a, A: ?Sized> Eq for &'a mut A where A: Eq {}
915 #[stable(feature = "rust1", since = "1.0.0")]
916 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b mut B> for &'a A where A: PartialEq<B> {
918 fn eq(&self, other: &&'b mut B) -> bool { PartialEq::eq(*self, *other) }
920 fn ne(&self, other: &&'b mut B) -> bool { PartialEq::ne(*self, *other) }
923 #[stable(feature = "rust1", since = "1.0.0")]
924 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b B> for &'a mut A where A: PartialEq<B> {
926 fn eq(&self, other: &&'b B) -> bool { PartialEq::eq(*self, *other) }
928 fn ne(&self, other: &&'b B) -> bool { PartialEq::ne(*self, *other) }