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, B, C, D> Eq for unsafe fn(A, B, C, D) -> 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<Ret, A, B, C, D, E, F, G> Eq for unsafe fn(A, B, C, D, E, F, G) -> Retimpl<T> Eq for [T; 30] where
T: Eq,impl<Ret, A, B, C, D, E, F> Eq for unsafe fn(A, B, C, D, E, F) -> Retimpl<T> Eq for NonNull<T> where
T: ?Sized,impl Eq for CharTryFromErrorimpl<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, B, C, D, E> Eq for unsafe fn(A, B, C, D, E) -> Retimpl Eq for Durationimpl<Ret, A, B, C, D> Eq for extern "C" fn(A, B, C, D, ...) -> Retimpl Eq for i64impl<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; 19] where
T: Eq,impl Eq for UnicodeVersionimpl Eq for Utf8Errorimpl<T> Eq for [T; 4] where
T: Eq,impl<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<T> Eq for Option<T> where
T: Eq,impl Eq for u128impl<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<Ret, A, B, C, D, E, F, G, H> Eq for extern "C" fn(A, B, C, D, E, F, G, H) -> Retimpl Eq for SearchStepimpl<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; 9] where
T: Eq,impl Eq for charimpl Eq for u16impl Eq for isizeimpl<Ret, A, B, C, D, E, F, G> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, ...) -> Retimpl<Ret, A, B, C, D, E, F> Eq for extern "C" fn(A, B, C, D, E, F) -> Retimpl<T> Eq for [T] where
T: Eq,impl<T> Eq for Cell<T> where
T: Copy + Eq,impl<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> Eq for fn() -> Retimpl Eq for i32impl Eq for u64impl<A, B, C> Eq for (A, B, C) where
A: Eq,
B: Eq,
C: Eq + ?Sized,impl<T> Eq for [T; 10] where
T: Eq,impl<Idx> Eq for RangeFrom<Idx> where
Idx: Eq,impl<T> Eq for *const T where
T: ?Sized,impl<Ret, A> Eq for extern "C" fn(A, ...) -> Retimpl<Idx> Eq for RangeInclusive<Idx> where
Idx: Eq,impl<Ret, A> Eq for unsafe extern "C" fn(A) -> Retimpl<T> Eq for [T; 22] where
T: Eq,impl<Ret, A> Eq for unsafe fn(A) -> Retimpl<Ret, A, B, C, D, E, F> Eq for unsafe extern "C" fn(A, B, C, D, E, F) -> Retimpl Eq for boolimpl<T> Eq for Poll<T> where
T: Eq,impl Eq for Errorimpl<Ret, A, B, C, D, E, F, G> Eq for extern "C" fn(A, B, C, D, E, F, G, ...) -> Retimpl<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> Eq for unsafe fn(A, B, C) -> Retimpl<T> Eq for [T; 12] where
T: Eq,impl<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<T> Eq for [T; 24] where
T: Eq,impl<'a, A> Eq for &'a mut A where
A: Eq + ?Sized,impl<T> Eq for [T; 3] where
T: Eq,impl<'a, A> Eq for &'a A where
A: Eq + ?Sized,impl Eq for u8impl<T> Eq for [T; 23] where
T: Eq,impl<A> Eq for (A,) where
A: Eq + ?Sized,impl<Ret, A> Eq for fn(A) -> Retimpl<Ret, A, B, C, D, E> Eq for extern "C" fn(A, B, C, D, E, ...) -> Retimpl Eq for NonZeroUsizeimpl Eq for Orderingimpl Eq for DecodeUtf16Errorimpl<T> Eq for [T; 5] where
T: Eq,impl<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<Idx> Eq for RangeTo<Idx> where
Idx: Eq,impl<T> Eq for [T; 6] where
T: Eq,impl Eq for Layoutimpl<Ret, A, B, C, D, E, F> Eq for fn(A, B, C, D, E, F) -> 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; 18] where
T: Eq,impl<T> Eq for ManuallyDrop<T> where
T: Eq,impl<T> Eq for Wrapping<T> where
T: Eq,impl<T> Eq for [T; 13] where
T: Eq,impl<Ret, A, B, C> Eq for unsafe extern "C" fn(A, B, C) -> Retimpl<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 [T; 21] where
T: Eq,impl<T> Eq for [T; 2] where
T: Eq,impl Eq for RangeFullimpl Eq for NonZeroU64impl Eq for NonZeroU8impl<Ret, A, B> Eq for extern "C" fn(A, B, ...) -> Retimpl<Ret, A, B, C> Eq for extern "C" fn(A, B, C, ...) -> Retimpl<T> Eq for *mut T where
T: ?Sized,impl<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; 27] where
T: Eq,impl<Ret, A, B, C, D, E, F> Eq for extern "C" fn(A, B, C, D, E, F, ...) -> Retimpl Eq for strimpl<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> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I) -> Retimpl Eq for ()impl Eq for i16impl<T> Eq for [T; 26] where
T: Eq,impl<H> Eq for BuildHasherDefault<H>impl<A, B> Eq for (A, B) where
A: Eq,
B: Eq + ?Sized,impl Eq for i8impl Eq for usizeimpl<T> Eq for [T; 11] where
T: Eq,impl<T> Eq for [T; 17] where
T: Eq,impl<Ret, A, B, C, D, E> Eq for unsafe extern "C" fn(A, B, C, D, E, ...) -> Retimpl Eq for ParseIntErrorimpl<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> Eq for fn(A, B) -> Retimpl<Ret, A, B> Eq for unsafe extern "C" fn(A, B, ...) -> 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<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> Eq for unsafe extern "C" fn(A, B, C, D, E) -> Retimpl<Ret, A, B, C, D, E, F, G, H> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, ...) -> Retimpl Eq for TypeIdimpl<Ret, A, B, C, D> Eq for fn(A, B, C, D) -> Retimpl Eq for ParseFloatErrorimpl Eq for u32impl<Ret> Eq for unsafe fn() -> Retimpl<Ret, A> Eq for unsafe extern "C" fn(A, ...) -> Retimpl<Ret> Eq for extern "C" fn() -> 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<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<T> Eq for Bound<T> where
T: Eq,impl<Ret, A, B, C, D, E> Eq for fn(A, B, C, D, E) -> Retimpl<Ret, A, B> Eq for unsafe fn(A, B) -> Retimpl<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 Eq for ParseBoolErrorimpl<Y, R> Eq for GeneratorState<Y, R> where
R: Eq,
Y: Eq,impl<T> Eq for [T; 16] 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, 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; 25] where
T: 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> 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> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, ...) -> Retimpl Eq for NonZeroU32impl Eq for LayoutErrimpl<Ret, A, B, C, D, E, F, G, H, I> Eq for fn(A, B, C, D, E, F, G, H, I) -> Retimpl<Idx> Eq for RangeToInclusive<Idx> where
Idx: Eq,impl Eq for CannotReallocInPlaceimpl Eq for NonZeroU128impl<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<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<Ret, A, B, C, D> Eq for extern "C" fn(A, B, C, D) -> Retimpl<T> Eq for [T; 7] where
T: Eq,impl<T> Eq for [T; 28] where
T: Eq,impl<Ret, A, B, C> Eq for extern "C" fn(A, B, C) -> Retimpl Eq for InvalidSequenceimpl<Ret, A> Eq for extern "C" fn(A) -> Retimpl<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 Eq for NoneErrorimpl<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, L> Eq for fn(A, B, C, D, E, F, G, H, I, J, K, L) -> Retimpl Eq for AllocErrimpl<Ret, A, B, C> Eq for fn(A, B, C) -> Retimpl<Ret, A, B, C, D> Eq for unsafe extern "C" fn(A, B, C, D, ...) -> Retimpl Eq for i128impl<Ret, A, B, C> Eq for unsafe extern "C" fn(A, B, C, ...) -> Retimpl<Ret, A, B, C, D, E, F, G> Eq for fn(A, B, C, D, E, F, G) -> Retimpl<Ret, A, B> Eq for unsafe extern "C" fn(A, B) -> Retimpl Eq for !impl<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 Reverse<T> where
T: Eq,impl<T> Eq for [T; 29] where
T: Eq,impl<Ret, A, B, C, D, E, F, G, H> Eq for fn(A, B, C, D, E, F, G, H) -> Retimpl<Ret, A, B> Eq for extern "C" fn(A, B) -> Retimpl<T> Eq for RefCell<T> where
T: Eq + ?Sized,impl Eq for Pinnedimpl Eq for FpCategoryimpl<Ret, A, B, C, D, E, F, G, H, I> Eq for unsafe fn(A, B, C, D, E, F, G, H, I) -> Retimpl<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, E, F, G, H> Eq for unsafe fn(A, B, C, D, E, F, G, H) -> Retimpl<T> Eq for PhantomData<T> where
T: ?Sized,impl<T> Eq for [T; 8] where
T: Eq,impl<T, E> Eq for Result<T, E> where
E: Eq,
T: Eq,impl Eq for NonZeroU16impl<T> Eq for [T; 32] where
T: Eq,impl<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<T> Eq for Discriminant<T>impl<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 Eq for ParseCharErrorimpl<T> Eq for [T; 1] 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, G, H, I> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I, ...) -> Retimpl<T> Eq for [T; 31] where
T: Eq,impl<T> Eq for [T; 20] where
T: Eq,impl<T> Eq for [T; 0] where
T: Eq,impl<Ret> Eq for unsafe extern "C" fn() -> 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 [T; 14] where
T: Eq,impl<T> Eq for [T; 15] where
T: Eq,impl<Idx> Eq for Range<Idx> where
Idx: Eq,impl<T> Eq for Vec<T> where
T: Eq,impl<A> Eq for VecDeque<A> where
A: Eq,impl<'a, B> Eq for Cow<'a, B> where
B: Eq + ToOwned + ?Sized,impl<T> Eq for BTreeSet<T> where
T: Eq,impl<K, V> Eq for BTreeMap<K, V> where
K: Eq,
V: Eq,impl Eq for ParseErrorimpl<T> Eq for Box<T> where
T: Eq + ?Sized,impl Eq for CollectionAllocErrimpl<T> Eq for Rc<T> where
T: Eq + ?Sized,impl<T> Eq for Arc<T> where
T: Eq + ?Sized,impl Eq for Stringimpl<T> Eq for LinkedList<T> where
T: Eq,impl 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