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