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 pub trait PartialEq<Rhs: ?Sized = Self> {
106 /// This method tests for `self` and `other` values to be equal, and is used
108 #[stable(feature = "rust1", since = "1.0.0")]
109 fn eq(&self, other: &Rhs) -> bool;
111 /// This method tests for `!=`.
113 #[stable(feature = "rust1", since = "1.0.0")]
114 fn ne(&self, other: &Rhs) -> bool { !self.eq(other) }
117 /// Trait for equality comparisons which are [equivalence relations](
118 /// https://en.wikipedia.org/wiki/Equivalence_relation).
120 /// This means, that in addition to `a == b` and `a != b` being strict inverses, the equality must
121 /// be (for all `a`, `b` and `c`):
123 /// - reflexive: `a == a`;
124 /// - symmetric: `a == b` implies `b == a`; and
125 /// - transitive: `a == b` and `b == c` implies `a == c`.
127 /// This property cannot be checked by the compiler, and therefore `Eq` implies
128 /// `PartialEq`, and has no extra methods.
132 /// This trait can be used with `#[derive]`. When `derive`d, because `Eq` has
133 /// no extra methods, it is only informing the compiler that this is an
134 /// equivalence relation rather than a partial equivalence relation. Note that
135 /// the `derive` strategy requires all fields are `Eq`, which isn't
138 /// ## How can I implement `Eq`?
140 /// If you cannot use the `derive` strategy, specify that your type implements
141 /// `Eq`, which has no methods:
144 /// enum BookFormat { Paperback, Hardback, Ebook }
147 /// format: BookFormat,
149 /// impl PartialEq for Book {
150 /// fn eq(&self, other: &Book) -> bool {
151 /// self.isbn == other.isbn
154 /// impl Eq for Book {}
156 #[stable(feature = "rust1", since = "1.0.0")]
157 pub trait Eq: PartialEq<Self> {
158 // FIXME #13101: this method is used solely by #[deriving] to
159 // assert that every component of a type implements #[deriving]
160 // itself, the current deriving infrastructure means doing this
161 // assertion without using a method on this trait is nearly
164 // This should never be implemented by hand.
167 #[stable(feature = "rust1", since = "1.0.0")]
168 fn assert_receiver_is_total_eq(&self) {}
171 // FIXME: this struct is used solely by #[derive] to
172 // assert that every component of a type implements Eq.
174 // This struct should never appear in user code.
176 #[allow(missing_debug_implementations)]
177 #[unstable(feature = "derive_eq",
178 reason = "deriving hack, should not be public",
180 pub struct AssertParamIsEq<T: Eq + ?Sized> { _field: ::marker::PhantomData<T> }
182 /// An `Ordering` is the result of a comparison between two values.
187 /// use std::cmp::Ordering;
189 /// let result = 1.cmp(&2);
190 /// assert_eq!(Ordering::Less, result);
192 /// let result = 1.cmp(&1);
193 /// assert_eq!(Ordering::Equal, result);
195 /// let result = 2.cmp(&1);
196 /// assert_eq!(Ordering::Greater, result);
198 #[derive(Clone, Copy, PartialEq, Debug, Hash)]
199 #[stable(feature = "rust1", since = "1.0.0")]
201 /// An ordering where a compared value is less [than another].
202 #[stable(feature = "rust1", since = "1.0.0")]
204 /// An ordering where a compared value is equal [to another].
205 #[stable(feature = "rust1", since = "1.0.0")]
207 /// An ordering where a compared value is greater [than another].
208 #[stable(feature = "rust1", since = "1.0.0")]
213 /// Reverse the `Ordering`.
215 /// * `Less` becomes `Greater`.
216 /// * `Greater` becomes `Less`.
217 /// * `Equal` becomes `Equal`.
224 /// use std::cmp::Ordering;
226 /// assert_eq!(Ordering::Less.reverse(), Ordering::Greater);
227 /// assert_eq!(Ordering::Equal.reverse(), Ordering::Equal);
228 /// assert_eq!(Ordering::Greater.reverse(), Ordering::Less);
231 /// This method can be used to reverse a comparison:
234 /// let mut data: &mut [_] = &mut [2, 10, 5, 8];
236 /// // sort the array from largest to smallest.
237 /// data.sort_by(|a, b| a.cmp(b).reverse());
239 /// let b: &mut [_] = &mut [10, 8, 5, 2];
240 /// assert!(data == b);
243 #[stable(feature = "rust1", since = "1.0.0")]
244 pub fn reverse(self) -> Ordering {
252 /// Chains two orderings.
254 /// Returns `self` when it's not `Equal`. Otherwise returns `other`.
258 /// use std::cmp::Ordering;
260 /// let result = Ordering::Equal.then(Ordering::Less);
261 /// assert_eq!(result, Ordering::Less);
263 /// let result = Ordering::Less.then(Ordering::Equal);
264 /// assert_eq!(result, Ordering::Less);
266 /// let result = Ordering::Less.then(Ordering::Greater);
267 /// assert_eq!(result, Ordering::Less);
269 /// let result = Ordering::Equal.then(Ordering::Equal);
270 /// assert_eq!(result, Ordering::Equal);
272 /// let x: (i64, i64, i64) = (1, 2, 7);
273 /// let y: (i64, i64, i64) = (1, 5, 3);
274 /// let result = x.0.cmp(&y.0).then(x.1.cmp(&y.1)).then(x.2.cmp(&y.2));
276 /// assert_eq!(result, Ordering::Less);
279 #[stable(feature = "ordering_chaining", since = "1.17.0")]
280 pub fn then(self, other: Ordering) -> Ordering {
287 /// Chains the ordering with the given function.
289 /// Returns `self` when it's not `Equal`. Otherwise calls `f` and returns
295 /// use std::cmp::Ordering;
297 /// let result = Ordering::Equal.then_with(|| Ordering::Less);
298 /// assert_eq!(result, Ordering::Less);
300 /// let result = Ordering::Less.then_with(|| Ordering::Equal);
301 /// assert_eq!(result, Ordering::Less);
303 /// let result = Ordering::Less.then_with(|| Ordering::Greater);
304 /// assert_eq!(result, Ordering::Less);
306 /// let result = Ordering::Equal.then_with(|| Ordering::Equal);
307 /// assert_eq!(result, Ordering::Equal);
309 /// let x: (i64, i64, i64) = (1, 2, 7);
310 /// let y: (i64, i64, i64) = (1, 5, 3);
311 /// let result = x.0.cmp(&y.0).then_with(|| x.1.cmp(&y.1)).then_with(|| x.2.cmp(&y.2));
313 /// assert_eq!(result, Ordering::Less);
316 #[stable(feature = "ordering_chaining", since = "1.17.0")]
317 pub fn then_with<F: FnOnce() -> Ordering>(self, f: F) -> Ordering {
325 /// Trait for types that form a [total order](https://en.wikipedia.org/wiki/Total_order).
327 /// An order is a total order if it is (for all `a`, `b` and `c`):
329 /// - total and antisymmetric: exactly one of `a < b`, `a == b` or `a > b` is true; and
330 /// - transitive, `a < b` and `b < c` implies `a < c`. The same must hold for both `==` and `>`.
334 /// This trait can be used with `#[derive]`. When `derive`d, it will produce a lexicographic
335 /// ordering based on the top-to-bottom declaration order of the struct's members.
337 /// ## How can I implement `Ord`?
339 /// `Ord` requires that the type also be `PartialOrd` and `Eq` (which requires `PartialEq`).
341 /// Then you must define an implementation for `cmp()`. You may find it useful to use
342 /// `cmp()` on your type's fields.
344 /// Here's an example where you want to sort people by height only, disregarding `id`
348 /// use std::cmp::Ordering;
357 /// impl Ord for Person {
358 /// fn cmp(&self, other: &Person) -> Ordering {
359 /// self.height.cmp(&other.height)
363 /// impl PartialOrd for Person {
364 /// fn partial_cmp(&self, other: &Person) -> Option<Ordering> {
365 /// Some(self.cmp(other))
369 /// impl PartialEq for Person {
370 /// fn eq(&self, other: &Person) -> bool {
371 /// self.height == other.height
375 #[stable(feature = "rust1", since = "1.0.0")]
376 pub trait Ord: Eq + PartialOrd<Self> {
377 /// This method returns an `Ordering` between `self` and `other`.
379 /// By convention, `self.cmp(&other)` returns the ordering matching the expression
380 /// `self <operator> other` if true.
385 /// use std::cmp::Ordering;
387 /// assert_eq!(5.cmp(&10), Ordering::Less);
388 /// assert_eq!(10.cmp(&5), Ordering::Greater);
389 /// assert_eq!(5.cmp(&5), Ordering::Equal);
391 #[stable(feature = "rust1", since = "1.0.0")]
392 fn cmp(&self, other: &Self) -> Ordering;
395 #[stable(feature = "rust1", since = "1.0.0")]
396 impl Eq for Ordering {}
398 #[stable(feature = "rust1", since = "1.0.0")]
399 impl Ord for Ordering {
401 fn cmp(&self, other: &Ordering) -> Ordering {
402 (*self as i32).cmp(&(*other as i32))
406 #[stable(feature = "rust1", since = "1.0.0")]
407 impl PartialOrd for Ordering {
409 fn partial_cmp(&self, other: &Ordering) -> Option<Ordering> {
410 (*self as i32).partial_cmp(&(*other as i32))
414 /// Trait for values that can be compared for a sort-order.
416 /// The comparison must satisfy, for all `a`, `b` and `c`:
418 /// - antisymmetry: if `a < b` then `!(a > b)`, as well as `a > b` implying `!(a < b)`; and
419 /// - transitivity: `a < b` and `b < c` implies `a < c`. The same must hold for both `==` and `>`.
421 /// Note that these requirements mean that the trait itself must be implemented symmetrically and
422 /// transitively: if `T: PartialOrd<U>` and `U: PartialOrd<V>` then `U: PartialOrd<T>` and `T:
427 /// This trait can be used with `#[derive]`. When `derive`d, it will produce a lexicographic
428 /// ordering based on the top-to-bottom declaration order of the struct's members.
430 /// ## How can I implement `PartialOrd`?
432 /// PartialOrd only requires implementation of the `partial_cmp` method, with the others generated
433 /// from default implementations.
435 /// However it remains possible to implement the others separately for types which do not have a
436 /// total order. For example, for floating point numbers, `NaN < 0 == false` and `NaN >= 0 ==
437 /// false` (cf. IEEE 754-2008 section 5.11).
439 /// `PartialOrd` requires your type to be `PartialEq`.
441 /// If your type is `Ord`, you can implement `partial_cmp()` by using `cmp()`:
444 /// use std::cmp::Ordering;
453 /// impl PartialOrd for Person {
454 /// fn partial_cmp(&self, other: &Person) -> Option<Ordering> {
455 /// Some(self.cmp(other))
459 /// impl Ord for Person {
460 /// fn cmp(&self, other: &Person) -> Ordering {
461 /// self.height.cmp(&other.height)
465 /// impl PartialEq for Person {
466 /// fn eq(&self, other: &Person) -> bool {
467 /// self.height == other.height
472 /// You may also find it useful to use `partial_cmp()` on your type's fields. Here
473 /// is an example of `Person` types who have a floating-point `height` field that
474 /// is the only field to be used for sorting:
477 /// use std::cmp::Ordering;
485 /// impl PartialOrd for Person {
486 /// fn partial_cmp(&self, other: &Person) -> Option<Ordering> {
487 /// self.height.partial_cmp(&other.height)
491 /// impl PartialEq for Person {
492 /// fn eq(&self, other: &Person) -> bool {
493 /// self.height == other.height
504 /// assert_eq!(x < y, true);
505 /// assert_eq!(x.lt(&y), true);
508 #[stable(feature = "rust1", since = "1.0.0")]
509 pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> {
510 /// This method returns an ordering between `self` and `other` values if one exists.
515 /// use std::cmp::Ordering;
517 /// let result = 1.0.partial_cmp(&2.0);
518 /// assert_eq!(result, Some(Ordering::Less));
520 /// let result = 1.0.partial_cmp(&1.0);
521 /// assert_eq!(result, Some(Ordering::Equal));
523 /// let result = 2.0.partial_cmp(&1.0);
524 /// assert_eq!(result, Some(Ordering::Greater));
527 /// When comparison is impossible:
530 /// let result = std::f64::NAN.partial_cmp(&1.0);
531 /// assert_eq!(result, None);
533 #[stable(feature = "rust1", since = "1.0.0")]
534 fn partial_cmp(&self, other: &Rhs) -> Option<Ordering>;
536 /// This method tests less than (for `self` and `other`) and is used by the `<` operator.
541 /// let result = 1.0 < 2.0;
542 /// assert_eq!(result, true);
544 /// let result = 2.0 < 1.0;
545 /// assert_eq!(result, false);
548 #[stable(feature = "rust1", since = "1.0.0")]
549 fn lt(&self, other: &Rhs) -> bool {
550 match self.partial_cmp(other) {
556 /// This method tests less than or equal to (for `self` and `other`) and is used by the `<=`
562 /// let result = 1.0 <= 2.0;
563 /// assert_eq!(result, true);
565 /// let result = 2.0 <= 2.0;
566 /// assert_eq!(result, true);
569 #[stable(feature = "rust1", since = "1.0.0")]
570 fn le(&self, other: &Rhs) -> bool {
571 match self.partial_cmp(other) {
572 Some(Less) | Some(Equal) => true,
577 /// This method tests greater than (for `self` and `other`) and is used by the `>` operator.
582 /// let result = 1.0 > 2.0;
583 /// assert_eq!(result, false);
585 /// let result = 2.0 > 2.0;
586 /// assert_eq!(result, false);
589 #[stable(feature = "rust1", since = "1.0.0")]
590 fn gt(&self, other: &Rhs) -> bool {
591 match self.partial_cmp(other) {
592 Some(Greater) => true,
597 /// This method tests greater than or equal to (for `self` and `other`) and is used by the `>=`
603 /// let result = 2.0 >= 1.0;
604 /// assert_eq!(result, true);
606 /// let result = 2.0 >= 2.0;
607 /// assert_eq!(result, true);
610 #[stable(feature = "rust1", since = "1.0.0")]
611 fn ge(&self, other: &Rhs) -> bool {
612 match self.partial_cmp(other) {
613 Some(Greater) | Some(Equal) => true,
619 /// Compare and return the minimum of two values.
621 /// Returns the first argument if the comparison determines them to be equal.
628 /// assert_eq!(1, cmp::min(1, 2));
629 /// assert_eq!(2, cmp::min(2, 2));
632 #[stable(feature = "rust1", since = "1.0.0")]
633 pub fn min<T: Ord>(v1: T, v2: T) -> T {
634 if v1 <= v2 { v1 } else { v2 }
637 /// Compare and return the maximum of two values.
639 /// Returns the second argument if the comparison determines them to be equal.
646 /// assert_eq!(2, cmp::max(1, 2));
647 /// assert_eq!(2, cmp::max(2, 2));
650 #[stable(feature = "rust1", since = "1.0.0")]
651 pub fn max<T: Ord>(v1: T, v2: T) -> T {
652 if v2 >= v1 { v2 } else { v1 }
655 // Implementation of PartialEq, Eq, PartialOrd and Ord for primitive types
657 use cmp::Ordering::{self, Less, Greater, Equal};
659 macro_rules! partial_eq_impl {
661 #[stable(feature = "rust1", since = "1.0.0")]
662 impl PartialEq for $t {
664 fn eq(&self, other: &$t) -> bool { (*self) == (*other) }
666 fn ne(&self, other: &$t) -> bool { (*self) != (*other) }
671 #[stable(feature = "rust1", since = "1.0.0")]
672 impl PartialEq for () {
674 fn eq(&self, _other: &()) -> bool { true }
676 fn ne(&self, _other: &()) -> bool { false }
680 bool char usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f32 f64
683 macro_rules! eq_impl {
685 #[stable(feature = "rust1", since = "1.0.0")]
690 eq_impl! { () bool char usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 }
692 macro_rules! partial_ord_impl {
694 #[stable(feature = "rust1", since = "1.0.0")]
695 impl PartialOrd for $t {
697 fn partial_cmp(&self, other: &$t) -> Option<Ordering> {
698 match (self <= other, self >= other) {
699 (false, false) => None,
700 (false, true) => Some(Greater),
701 (true, false) => Some(Less),
702 (true, true) => Some(Equal),
706 fn lt(&self, other: &$t) -> bool { (*self) < (*other) }
708 fn le(&self, other: &$t) -> bool { (*self) <= (*other) }
710 fn ge(&self, other: &$t) -> bool { (*self) >= (*other) }
712 fn gt(&self, other: &$t) -> bool { (*self) > (*other) }
717 #[stable(feature = "rust1", since = "1.0.0")]
718 impl PartialOrd for () {
720 fn partial_cmp(&self, _: &()) -> Option<Ordering> {
725 #[stable(feature = "rust1", since = "1.0.0")]
726 impl PartialOrd for bool {
728 fn partial_cmp(&self, other: &bool) -> Option<Ordering> {
729 (*self as u8).partial_cmp(&(*other as u8))
733 partial_ord_impl! { f32 f64 }
735 macro_rules! ord_impl {
737 #[stable(feature = "rust1", since = "1.0.0")]
738 impl PartialOrd for $t {
740 fn partial_cmp(&self, other: &$t) -> Option<Ordering> {
741 Some(self.cmp(other))
744 fn lt(&self, other: &$t) -> bool { (*self) < (*other) }
746 fn le(&self, other: &$t) -> bool { (*self) <= (*other) }
748 fn ge(&self, other: &$t) -> bool { (*self) >= (*other) }
750 fn gt(&self, other: &$t) -> bool { (*self) > (*other) }
753 #[stable(feature = "rust1", since = "1.0.0")]
756 fn cmp(&self, other: &$t) -> Ordering {
757 if *self == *other { Equal }
758 else if *self < *other { Less }
765 #[stable(feature = "rust1", since = "1.0.0")]
768 fn cmp(&self, _other: &()) -> Ordering { Equal }
771 #[stable(feature = "rust1", since = "1.0.0")]
774 fn cmp(&self, other: &bool) -> Ordering {
775 (*self as u8).cmp(&(*other as u8))
779 ord_impl! { char usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 }
781 #[unstable(feature = "never_type_impls", issue = "35121")]
782 impl PartialEq for ! {
783 fn eq(&self, _: &!) -> bool {
788 #[unstable(feature = "never_type_impls", issue = "35121")]
791 #[unstable(feature = "never_type_impls", issue = "35121")]
792 impl PartialOrd for ! {
793 fn partial_cmp(&self, _: &!) -> Option<Ordering> {
798 #[unstable(feature = "never_type_impls", issue = "35121")]
800 fn cmp(&self, _: &!) -> Ordering {
807 #[stable(feature = "rust1", since = "1.0.0")]
808 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b B> for &'a A where A: PartialEq<B> {
810 fn eq(&self, other: & &'b B) -> bool { PartialEq::eq(*self, *other) }
812 fn ne(&self, other: & &'b B) -> bool { PartialEq::ne(*self, *other) }
814 #[stable(feature = "rust1", since = "1.0.0")]
815 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialOrd<&'b B> for &'a A where A: PartialOrd<B> {
817 fn partial_cmp(&self, other: &&'b B) -> Option<Ordering> {
818 PartialOrd::partial_cmp(*self, *other)
821 fn lt(&self, other: & &'b B) -> bool { PartialOrd::lt(*self, *other) }
823 fn le(&self, other: & &'b B) -> bool { PartialOrd::le(*self, *other) }
825 fn ge(&self, other: & &'b B) -> bool { PartialOrd::ge(*self, *other) }
827 fn gt(&self, other: & &'b B) -> bool { PartialOrd::gt(*self, *other) }
829 #[stable(feature = "rust1", since = "1.0.0")]
830 impl<'a, A: ?Sized> Ord for &'a A where A: Ord {
832 fn cmp(&self, other: & &'a A) -> Ordering { Ord::cmp(*self, *other) }
834 #[stable(feature = "rust1", since = "1.0.0")]
835 impl<'a, A: ?Sized> Eq for &'a A where A: Eq {}
839 #[stable(feature = "rust1", since = "1.0.0")]
840 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b mut B> for &'a mut A where A: PartialEq<B> {
842 fn eq(&self, other: &&'b mut B) -> bool { PartialEq::eq(*self, *other) }
844 fn ne(&self, other: &&'b mut B) -> bool { PartialEq::ne(*self, *other) }
846 #[stable(feature = "rust1", since = "1.0.0")]
847 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialOrd<&'b mut B> for &'a mut A where A: PartialOrd<B> {
849 fn partial_cmp(&self, other: &&'b mut B) -> Option<Ordering> {
850 PartialOrd::partial_cmp(*self, *other)
853 fn lt(&self, other: &&'b mut B) -> bool { PartialOrd::lt(*self, *other) }
855 fn le(&self, other: &&'b mut B) -> bool { PartialOrd::le(*self, *other) }
857 fn ge(&self, other: &&'b mut B) -> bool { PartialOrd::ge(*self, *other) }
859 fn gt(&self, other: &&'b mut B) -> bool { PartialOrd::gt(*self, *other) }
861 #[stable(feature = "rust1", since = "1.0.0")]
862 impl<'a, A: ?Sized> Ord for &'a mut A where A: Ord {
864 fn cmp(&self, other: &&'a mut A) -> Ordering { Ord::cmp(*self, *other) }
866 #[stable(feature = "rust1", since = "1.0.0")]
867 impl<'a, A: ?Sized> Eq for &'a mut A where A: Eq {}
869 #[stable(feature = "rust1", since = "1.0.0")]
870 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b mut B> for &'a A where A: PartialEq<B> {
872 fn eq(&self, other: &&'b mut B) -> bool { PartialEq::eq(*self, *other) }
874 fn ne(&self, other: &&'b mut B) -> bool { PartialEq::ne(*self, *other) }
877 #[stable(feature = "rust1", since = "1.0.0")]
878 impl<'a, 'b, A: ?Sized, B: ?Sized> PartialEq<&'b B> for &'a mut A where A: PartialEq<B> {
880 fn eq(&self, other: &&'b B) -> bool { PartialEq::eq(*self, *other) }
882 fn ne(&self, other: &&'b B) -> bool { PartialEq::ne(*self, *other) }