Trait std::cmp::Eq 1.0.0[−][src]
pub trait Eq: PartialEq<Self> { }
Trait for equality comparisons which are equivalence relations.
This means, that in addition to a == b and a != b being strict inverses, the equality must
be (for all a, b and c):
- reflexive:
a == a; - symmetric:
a == bimpliesb == a; and - transitive:
a == bandb == cimpliesa == c.
This property cannot be checked by the compiler, and therefore Eq implies
PartialEq, and has no extra methods.
Derivable
This trait can be used with #[derive]. When derived, because Eq has
no extra methods, it is only informing the compiler that this is an
equivalence relation rather than a partial equivalence relation. Note that
the derive strategy requires all fields are Eq, which isn't
always desired.
How can I implement Eq?
If you cannot use the derive strategy, specify that your type implements
Eq, which has no methods:
enum BookFormat { Paperback, Hardback, Ebook } struct Book { isbn: i32, format: BookFormat, } impl PartialEq for Book { fn eq(&self, other: &Book) -> bool { self.isbn == other.isbn } } impl Eq for Book {}Run
Implementations on Foreign Types
impl<'a> Eq for Utf8LossyChunk<'a>[src]
impl<'a> Eq for Utf8LossyChunk<'a>Implementors
impl<Ret, A> Eq for unsafe fn(A) -> Retimpl<T, E> Eq for Result<T, E> where
E: Eq,
T: Eq,impl Eq for CharTryFromErrorimpl<A, B, C, D, E, F, G, H, I> Eq for (A, B, C, D, E, F, G, H, I) where
A: Eq,
B: Eq,
C: Eq,
D: Eq,
E: Eq,
F: Eq,
G: Eq,
H: Eq,
I: Eq + ?Sized,impl<Ret, A, B, C, D> Eq for fn(A, B, C, D) -> Retimpl<Ret> Eq for unsafe fn() -> Retimpl<Idx> Eq for RangeInclusive<Idx> where
Idx: Eq,impl Eq for NonZeroU32impl Eq for NonZeroUsizeimpl Eq for LayoutErrimpl<'a, A> Eq for &'a mut A where
A: Eq + ?Sized,impl<A, B, C, D, E, F, G, H> Eq for (A, B, C, D, E, F, G, H) where
A: Eq,
B: Eq,
C: Eq,
D: Eq,
E: Eq,
F: Eq,
G: Eq,
H: Eq + ?Sized,impl<A, B, C> Eq for (A, B, C) where
A: Eq,
B: Eq,
C: Eq + ?Sized,impl<Ret, A, B> Eq for unsafe fn(A, B) -> Retimpl<T> Eq for [T; 21] where
T: Eq,impl<A, B, C, D, E, F, G, H, I, J, K, L> Eq for (A, B, C, D, E, F, G, H, I, J, K, L) where
A: Eq,
B: Eq,
C: Eq,
D: Eq,
E: Eq,
F: Eq,
G: Eq,
H: Eq,
I: Eq,
J: Eq,
K: Eq,
L: Eq + ?Sized,impl<Ret, A> Eq for fn(A) -> Retimpl<Ret, A, B, C, D, E, F, G> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, ...) -> Retimpl<A, B> Eq for (A, B) where
A: Eq,
B: Eq + ?Sized,impl<Ret, A, B, C, D, E> Eq for unsafe fn(A, B, C, D, E) -> Retimpl Eq for ParseIntErrorimpl Eq for strimpl<Ret, A, B, C, D, E, F, G, H, I, J, K> Eq for unsafe fn(A, B, C, D, E, F, G, H, I, J, K) -> Retimpl<T> Eq for [T; 8] where
T: Eq,impl Eq for i32impl<Ret> Eq for fn() -> Retimpl<Ret, A, B> Eq for fn(A, B) -> Retimpl<Y, R> Eq for GeneratorState<Y, R> where
R: Eq,
Y: Eq,impl<A, B, C, D> Eq for (A, B, C, D) where
A: Eq,
B: Eq,
C: Eq,
D: Eq + ?Sized,impl<Ret, A, B, C, D, E, F, G, H, I> Eq for fn(A, B, C, D, E, F, G, H, I) -> Retimpl<T> Eq for [T; 11] where
T: Eq,impl<Ret, A, B, C, D, E, F, G> Eq for extern "C" fn(A, B, C, D, E, F, G, ...) -> Retimpl<H> Eq for BuildHasherDefault<H>impl<T> Eq for [T; 28] where
T: Eq,impl<Ret, A, B, C, D, E> Eq for extern "C" fn(A, B, C, D, E) -> Retimpl<Ret, A, B, C, D, E, F> Eq for extern "C" fn(A, B, C, D, E, F) -> Retimpl<T> Eq for [T; 10] where
T: Eq,impl<T> Eq for [T; 13] where
T: Eq,impl<Ret, A, B, C, D, E, F, G, H, I, J, K> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, K) -> Retimpl<Ret, A> Eq for unsafe extern "C" fn(A, ...) -> Retimpl Eq for Orderingimpl Eq for i64impl<T> Eq for [T; 32] where
T: Eq,impl<Ret, A, B, C, D, E, F, G> Eq for unsafe fn(A, B, C, D, E, F, G) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I) -> Retimpl<T> Eq for [T; 26] where
T: Eq,impl<Idx> Eq for RangeTo<Idx> where
Idx: Eq,impl<Ret, A, B, C, D> Eq for extern "C" fn(A, B, C, D) -> Retimpl<T> Eq for ManuallyDrop<T> where
T: Eq,impl Eq for i16impl<Ret, A, B> Eq for extern "C" fn(A, B) -> Retimpl<Ret, A, B, C, D, E, F> Eq for extern "C" fn(A, B, C, D, E, F, ...) -> Retimpl<Idx> Eq for RangeToInclusive<Idx> where
Idx: Eq,impl<Ret, A, B, C, D, E, F, G, H, I, J, K> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, ...) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I, J> Eq for fn(A, B, C, D, E, F, G, H, I, J) -> Retimpl<T> Eq for [T; 12] where
T: Eq,impl<T> Eq for [T; 20] where
T: Eq,impl Eq for NonZeroU8impl<A, B, C, D, E> Eq for (A, B, C, D, E) where
A: Eq,
B: Eq,
C: Eq,
D: Eq,
E: Eq + ?Sized,impl<T> Eq for [T; 23] where
T: Eq,impl<T> Eq for [T; 5] where
T: Eq,impl<Ret, A, B, C> Eq for unsafe extern "C" fn(A, B, C) -> Retimpl<T> Eq for [T; 4] where
T: Eq,impl<Ret, A> Eq for extern "C" fn(A) -> Retimpl<Ret, A, B, C, D, E, F, G, H> Eq for fn(A, B, C, D, E, F, G, H) -> Retimpl Eq for !impl<T> Eq for [T; 7] where
T: Eq,impl<Ret, A, B, C> Eq for extern "C" fn(A, B, C) -> Retimpl Eq for NoneErrorimpl Eq for ParseCharErrorimpl<Ret, A, B, C, D, E> Eq for unsafe extern "C" fn(A, B, C, D, E) -> Retimpl<T> Eq for [T; 19] where
T: Eq,impl Eq for Durationimpl Eq for UnicodeVersionimpl<T> Eq for [T; 30] where
T: Eq,impl Eq for DecodeUtf16Errorimpl<A, B, C, D, E, F, G, H, I, J, K> Eq for (A, B, C, D, E, F, G, H, I, J, K) where
A: Eq,
B: Eq,
C: Eq,
D: Eq,
E: Eq,
F: Eq,
G: Eq,
H: Eq,
I: Eq,
J: Eq,
K: Eq + ?Sized,impl Eq for TypeIdimpl<T> Eq for PhantomData<T> where
T: ?Sized,impl<T> Eq for Reverse<T> where
T: Eq,impl Eq for Pinnedimpl Eq for isizeimpl<Ret, A, B, C, D, E, F, G, H, I, J, K> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I, J, K) -> Retimpl<Ret, A, B, C> Eq for unsafe extern "C" fn(A, B, C, ...) -> Retimpl<T> Eq for [T; 16] where
T: Eq,impl<Ret, A> Eq for extern "C" fn(A, ...) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I, J> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I, J, ...) -> Retimpl<Ret, A, B, C, D> Eq for unsafe extern "C" fn(A, B, C, D) -> Retimpl<Ret, A> Eq for unsafe extern "C" fn(A) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I, J> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, ...) -> Retimpl<T> Eq for [T; 6] where
T: Eq,impl Eq for boolimpl<T> Eq for [T; 31] where
T: Eq,impl<'a, A> Eq for &'a A where
A: Eq + ?Sized,impl Eq for usizeimpl Eq for u8impl<Ret, A, B> Eq for unsafe extern "C" fn(A, B) -> Retimpl Eq for u32impl<Ret, A, B, C, D, E, F, G, H> Eq for unsafe fn(A, B, C, D, E, F, G, H) -> Retimpl<Ret, A, B, C, D, E> Eq for unsafe extern "C" fn(A, B, C, D, E, ...) -> Retimpl<Ret, A, B, C, D, E, F> Eq for fn(A, B, C, D, E, F) -> Retimpl Eq for Errorimpl<Ret, A, B, C, D, E, F> Eq for unsafe extern "C" fn(A, B, C, D, E, F, ...) -> Retimpl<T> Eq for [T; 18] where
T: Eq,impl Eq for ParseFloatErrorimpl Eq for i8impl Eq for i128impl<T> Eq for Discriminant<T>impl Eq for SearchStepimpl<A, B, C, D, E, F, G, H, I, J> Eq for (A, B, C, D, E, F, G, H, I, J) where
A: Eq,
B: Eq,
C: Eq,
D: Eq,
E: Eq,
F: Eq,
G: Eq,
H: Eq,
I: Eq,
J: Eq + ?Sized,impl<T> Eq for [T; 9] where
T: Eq,impl<T> Eq for [T; 27] where
T: Eq,impl Eq for RangeFullimpl<A, B, C, D, E, F> Eq for (A, B, C, D, E, F) where
A: Eq,
B: Eq,
C: Eq,
D: Eq,
E: Eq,
F: Eq + ?Sized,impl<Ret, A, B> Eq for unsafe extern "C" fn(A, B, ...) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, L, ...) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I, ...) -> Retimpl<Ret, A, B, C> Eq for unsafe fn(A, B, C) -> Retimpl Eq for ()impl Eq for u16impl<Ret, A, B, C, D, E, F, G, H, I, J> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, L) -> Retimpl<T> Eq for RefCell<T> where
T: Eq + ?Sized,impl<Ret, A, B, C, D, E, F, G, H, I, J, K> Eq for fn(A, B, C, D, E, F, G, H, I, J, K) -> Retimpl Eq for NonZeroU128impl<Ret, A, B, C, D, E, F, G, H, I, J> Eq for unsafe fn(A, B, C, D, E, F, G, H, I, J) -> Retimpl<T> Eq for [T; 29] where
T: Eq,impl<T> Eq for *const T where
T: ?Sized,impl<T> Eq for *mut T where
T: ?Sized,impl<T> Eq for [T; 2] where
T: Eq,impl<T> Eq for [T; 15] where
T: Eq,impl<Ret, A, B, C, D, E, F, G, H, I> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, ...) -> Retimpl<Ret, A, B, C, D, E> Eq for extern "C" fn(A, B, C, D, E, ...) -> Retimpl<Ret, A, B, C, D> Eq for unsafe fn(A, B, C, D) -> Retimpl<Ret, A, B, C, D, E, F, G> Eq for fn(A, B, C, D, E, F, G) -> Retimpl<T> Eq for Bound<T> where
T: Eq,impl<Idx> Eq for Range<Idx> where
Idx: Eq,impl<Ret, A, B, C, D> Eq for extern "C" fn(A, B, C, D, ...) -> Retimpl<T> Eq for [T; 25] where
T: Eq,impl<Ret, A, B, C, D, E, F, G, H, I> Eq for unsafe fn(A, B, C, D, E, F, G, H, I) -> Retimpl<Ret, A, B, C, D, E> Eq for fn(A, B, C, D, E) -> Retimpl<T> Eq for Cell<T> where
T: Copy + Eq,impl Eq for CannotReallocInPlaceimpl<Ret, A, B, C, D, E, F, G, H> Eq for extern "C" fn(A, B, C, D, E, F, G, H, ...) -> Retimpl<Ret, A, B, C, D, E, F, G, H> Eq for extern "C" fn(A, B, C, D, E, F, G, H) -> Retimpl<T> Eq for [T; 3] where
T: Eq,impl Eq for Layoutimpl Eq for Utf8Errorimpl<Ret, A, B, C> Eq for extern "C" fn(A, B, C, ...) -> Retimpl<A, B, C, D, E, F, G> Eq for (A, B, C, D, E, F, G) where
A: Eq,
B: Eq,
C: Eq,
D: Eq,
E: Eq,
F: Eq,
G: Eq + ?Sized,impl Eq for AllocErrimpl Eq for NonZeroU64impl<T> Eq for [T; 22] where
T: Eq,impl<Ret> Eq for extern "C" fn() -> Retimpl<T> Eq for Option<T> where
T: Eq,impl Eq for FpCategoryimpl<Ret, A, B> Eq for extern "C" fn(A, B, ...) -> Retimpl Eq for u128impl<Idx> Eq for RangeFrom<Idx> where
Idx: Eq,impl<Ret, A, B, C, D, E, F, G> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G) -> Retimpl<T> Eq for Wrapping<T> where
T: Eq,impl Eq for charimpl<T> Eq for NonNull<T> where
T: ?Sized,impl Eq for ParseBoolErrorimpl<Ret, A, B, C, D, E, F, G, H, I, J> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I, J) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, L) -> Retimpl<Ret, A, B, C, D, E, F> Eq for unsafe extern "C" fn(A, B, C, D, E, F) -> Retimpl<T> Eq for [T] where
T: Eq,impl<Ret, A, B, C, D, E, F, G, H> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, ...) -> Retimpl<T> Eq for [T; 1] where
T: Eq,impl<Ret, A, B, C, D> Eq for unsafe extern "C" fn(A, B, C, D, ...) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I, J, K> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, ...) -> Retimpl Eq for NonZeroU16impl<Ret, A, B, C, D, E, F, G, H> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, L, ...) -> Retimpl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Eq for fn(A, B, C, D, E, F, G, H, I, J, K, L) -> Retimpl<Ret, A, B, C, D, E, F> Eq for unsafe fn(A, B, C, D, E, F) -> Retimpl Eq for InvalidSequenceimpl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Eq for unsafe fn(A, B, C, D, E, F, G, H, I, J, K, L) -> Retimpl<T> Eq for [T; 24] where
T: Eq,impl<T> Eq for Poll<T> where
T: Eq,impl<A> Eq for (A,) where
A: Eq + ?Sized,impl<T> Eq for [T; 14] where
T: Eq,impl<Ret, A, B, C, D, E, F, G, H, I> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I) -> Retimpl Eq for u64impl<T> Eq for [T; 0] where
T: Eq,impl<Ret, A, B, C, D, E, F, G> Eq for extern "C" fn(A, B, C, D, E, F, G) -> Retimpl<T> Eq for [T; 17] where
T: Eq,impl<Ret> Eq for unsafe extern "C" fn() -> Retimpl<Ret, A, B, C> Eq for fn(A, B, C) -> Retimpl Eq for ParseErrorimpl<T> Eq for LinkedList<T> where
T: Eq,impl<A> Eq for VecDeque<A> where
A: Eq,impl<T> Eq for BTreeSet<T> where
T: Eq,impl<T> Eq for Vec<T> where
T: Eq,impl<T> Eq for Rc<T> where
T: Eq + ?Sized,impl<'a, B> Eq for Cow<'a, B> where
B: Eq + ToOwned + ?Sized,impl Eq for CollectionAllocErrimpl<T> Eq for Box<T> where
T: Eq + ?Sized,impl<T> Eq for Arc<T> where
T: Eq + ?Sized,impl<K, V> Eq for BTreeMap<K, V> where
K: Eq,
V: Eq,impl Eq for Stringimpl Eq for ThreadIdimpl<K, V, S> Eq for HashMap<K, V, S> where
K: Eq + Hash,
V: Eq,
S: BuildHasher,impl<T, S> Eq for HashSet<T, S> where
T: Eq + Hash,
S: BuildHasher,impl Eq for VarErrorimpl Eq for CStringimpl Eq for NulErrorimpl Eq for FromBytesWithNulErrorimpl Eq for IntoStringErrorimpl Eq for CStrimpl Eq for OsStringimpl Eq for OsStrimpl Eq for Permissionsimpl Eq for FileTypeimpl Eq for ErrorKindimpl Eq for SeekFromimpl Eq for IpAddrimpl Eq for Ipv6MulticastScopeimpl Eq for Ipv4Addrimpl Eq for Ipv6Addrimpl Eq for SocketAddrimpl Eq for SocketAddrV4impl Eq for SocketAddrV6impl Eq for AddrParseErrorimpl Eq for Shutdownimpl<'a> Eq for Prefix<'a>impl<'a> Eq for PrefixComponent<'a>impl<'a> Eq for Component<'a>impl<'a> Eq for Components<'a>impl Eq for PathBufimpl Eq for StripPrefixErrorimpl Eq for Pathimpl Eq for Outputimpl Eq for ExitStatusimpl<T: Eq> Eq for SendError<T>impl Eq for RecvErrorimpl Eq for TryRecvErrorimpl Eq for RecvTimeoutErrorimpl<T: Eq> Eq for TrySendError<T>impl Eq for WaitTimeoutResultimpl Eq for Instantimpl Eq for SystemTime