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 Eq for ParseBoolErrorimpl Eq for Orderingimpl<Ret> Eq for unsafe fn() -> Retimpl<T> Eq for Cell<T> where
T: Copy + 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<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<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 *mut T where
T: ?Sized,impl Eq for m8x16impl Eq for m16x4impl Eq for AllocErrimpl Eq for i128impl<T> Eq for [T; 6] where
T: Eq,impl Eq for RangeFullimpl<Ret, A, B, C, D, E, F, G> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G) -> Retimpl Eq for i16x8impl<Ret, A, B, C, D, E, F, G> Eq for 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, 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> Eq for fn(A, B) -> Retimpl Eq for m16x8impl<T> Eq for [T; 15] 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<Ret, A, B, C, D, E, F, G, H> Eq for fn(A, B, C, D, E, F, G, H) -> 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 Eq for m32x2impl<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 u32x4impl<Ret, A, B, C, D, E> Eq for unsafe extern "C" fn(A, B, C, D, E) -> Retimpl<T> Eq for [T; 10] where
T: Eq,impl<'a, A> Eq for &'a A where
A: Eq + ?Sized,impl Eq for TypeIdimpl Eq for i64x4impl<Idx> Eq for RangeInclusive<Idx> where
Idx: Eq,impl Eq for i8x32impl<T> Eq for [T; 1] where
T: Eq,impl Eq for Errorimpl<T> Eq for [T; 17] where
T: Eq,impl<T> Eq for [T; 2] where
T: Eq,impl<T> Eq for [T; 4] where
T: Eq,impl<Ret> Eq for unsafe extern "C" fn() -> Retimpl Eq for ParseFloatErrorimpl<Ret, A, B, C, D, E, F, G> Eq for extern "C" fn(A, B, C, D, E, F, G) -> Retimpl Eq for isizeimpl Eq for m1x16impl<T, E> Eq for Result<T, E> where
E: Eq,
T: Eq,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 [T; 26] where
T: Eq,impl<Ret, A, B, C, D, E, F> Eq for fn(A, B, C, D, E, F) -> 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<Ret, A, B, C> Eq for unsafe fn(A, B, C) -> Retimpl Eq for Durationimpl<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; 21] 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> Eq for fn(A, B, C, D) -> Retimpl Eq for m64x2impl Eq for u16x2impl Eq for i16x4impl<T> Eq for Reverse<T> where
T: Eq,impl<A, B> Eq for (A, B) where
A: Eq,
B: Eq + ?Sized,impl<T> Eq for Bound<T> where
T: Eq,impl Eq for m1x32impl Eq for m32x4impl<T> Eq for [T; 12] where
T: Eq,impl Eq for !impl<T> Eq for [T; 31] where
T: Eq,impl Eq for u32x2impl Eq for CollectionAllocErrimpl<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 u16x16impl<Ret, A, B, C, D, E> Eq for extern "C" fn(A, B, C, D, E, ...) -> Retimpl Eq for u32impl<Ret, A, B, C> Eq for unsafe extern "C" fn(A, B, C, ...) -> Retimpl<T> Eq for [T; 22] where
T: Eq,impl<T> Eq for Discriminant<T>impl<Ret, A, B> Eq for extern "C" fn(A, B) -> 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<A> Eq for (A,) where
A: Eq + ?Sized,impl<T> Eq for [T; 20] where
T: Eq,impl<T> Eq for [T] where
T: Eq,impl Eq for m1x64impl Eq for charimpl Eq for i8x16impl Eq for SearchStepimpl Eq for m8x8impl Eq for m8x4impl Eq for i64x2impl Eq for u16x32impl<Ret, A, B> Eq for extern "C" fn(A, B, ...) -> Retimpl<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 unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, K) -> Retimpl Eq for CannotReallocInPlaceimpl<A, B, C> Eq for (A, B, C) where
A: Eq,
B: Eq,
C: Eq + ?Sized,impl<T> Eq for NonNull<T> where
T: ?Sized,impl Eq for m16x2impl Eq for Layoutimpl<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 unsafe fn(A, B, C, D, E, F, G, H, I, J, K) -> Retimpl<Idx> Eq for Range<Idx> where
Idx: Eq,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 m1x8impl Eq for boolimpl Eq for u8x64impl Eq for CharTryFromErrorimpl<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> Eq for extern "C" fn(A, B, C, D) -> Retimpl<Ret, A, B> Eq for unsafe fn(A, B) -> Retimpl Eq for NonZeroU64impl Eq for ParseCharErrorimpl<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 Eq for i8x8impl<Ret, A, B, C> Eq for extern "C" fn(A, B, C, ...) -> Retimpl Eq for u32x16impl Eq for m16x16impl<T> Eq for [T; 27] where
T: Eq,impl Eq for NonZeroU16impl<A, B, C, D> Eq for (A, B, C, D) where
A: Eq,
B: Eq,
C: Eq,
D: Eq + ?Sized,impl Eq for i64impl<T> Eq for [T; 0] where
T: Eq,impl<T> Eq for RefCell<T> where
T: Eq + ?Sized,impl Eq for DecodeUtf16Errorimpl<Ret> Eq for fn() -> Retimpl<Ret, A, B, C> Eq for unsafe extern "C" fn(A, B, C) -> Retimpl<T> Eq for [T; 30] where
T: Eq,impl<T> Eq for [T; 28] where
T: Eq,impl Eq for u64x2impl<Ret, A> Eq for extern "C" fn(A, ...) -> Retimpl<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<T> Eq for [T; 9] where
T: Eq,impl Eq for u128impl Eq for u8x2impl Eq for i8x4impl<Ret, A> Eq for extern "C" fn(A) -> Retimpl Eq for m32x8impl<T> Eq for [T; 8] 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<Ret, A, B, C, D, E, F> Eq for unsafe fn(A, B, C, D, E, F) -> Retimpl Eq for u64x4impl Eq for u8impl<Ret> Eq for extern "C" fn() -> Retimpl Eq for u8x32impl<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 Wrapping<T> where
T: Eq,impl Eq for u16x4impl<Ret, A, B, C, D, E, F, G> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, ...) -> Retimpl Eq for i32x4impl<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, G, H> Eq for unsafe fn(A, B, C, D, E, F, G, H) -> Retimpl<T> Eq for [T; 19] where
T: Eq,impl Eq for i8x64impl<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 fn(A, B, C, D, E) -> 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; 3] where
T: Eq,impl<T> Eq for [T; 16] where
T: Eq,impl Eq for Pinnedimpl<Idx> Eq for RangeFrom<Idx> where
Idx: 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 i32x16impl Eq for i16x2impl<Ret, A, B, C, D> Eq for extern "C" fn(A, B, C, D, ...) -> Retimpl Eq for i64x8impl<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, D, E, F, G, H, I> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, ...) -> Retimpl Eq for NonZeroU32impl<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 i32x2impl<T> Eq for [T; 11] where
T: Eq,impl<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; 7] where
T: Eq,impl<T> Eq for [T; 13] where
T: Eq,impl Eq for u8x16impl<Ret, A, B, C> Eq for extern "C" fn(A, B, C) -> Retimpl Eq for usizeimpl<Y, R> Eq for GeneratorState<Y, R> where
R: Eq,
Y: 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 Eq for ParseIntErrorimpl<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> Eq for extern "C" fn(A, B, C, D, E) -> Retimpl Eq for Utf8Errorimpl<Ret, A, B, C, D, E, F> Eq for extern "C" fn(A, B, C, D, E, F, ...) -> Retimpl<T> Eq for ManuallyDrop<T> where
T: Eq,impl Eq for UnicodeVersionimpl<Ret, A, B> Eq for unsafe extern "C" fn(A, B, ...) -> Retimpl<T> Eq for [T; 25] where
T: Eq,impl Eq for i16x16impl<Ret, A, B, C, D, E> Eq for unsafe fn(A, B, C, D, E) -> Retimpl Eq for strimpl<T> Eq for [T; 23] where
T: Eq,impl<Idx> Eq for RangeToInclusive<Idx> where
Idx: Eq,impl Eq for u64impl<Ret, A, B, C, D, E> Eq for unsafe extern "C" fn(A, B, C, D, E, ...) -> Retimpl<T> Eq for *const T where
T: ?Sized,impl<T> Eq for [T; 5] where
T: Eq,impl Eq for m64x4impl<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> Eq for unsafe extern "C" fn(A, B, C, D, E, F) -> Retimpl Eq for i16impl<T> Eq for [T; 18] where
T: Eq,impl<Ret, A, B, C, D> Eq for unsafe fn(A, B, C, D) -> Retimpl Eq for NonZeroU8impl<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> Eq for extern "C" fn(A, B, C, D, E, F) -> Retimpl<Ret, A, B, C> Eq for fn(A, B, C) -> Retimpl<T> Eq for Poll<T> where
T: Eq,impl Eq for i32impl Eq for u8x8impl Eq for i32x8impl<T> Eq for [T; 32] where
T: Eq,impl<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 i16x32impl Eq for NonZeroU128impl<Idx> Eq for RangeTo<Idx> where
Idx: Eq,impl Eq for u16x8impl<T> Eq for [T; 14] where
T: Eq,impl<T> Eq for Option<T> where
T: Eq,impl<Ret, A> Eq for fn(A) -> Retimpl<T> Eq for PhantomData<T> where
T: ?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 Eq for m8x32impl<Ret, A> Eq for unsafe extern "C" fn(A, ...) -> Retimpl<Ret, A, B> Eq for unsafe extern "C" fn(A, B) -> Retimpl Eq for ()impl Eq for u32x8impl<'a, A> Eq for &'a mut A where
A: Eq + ?Sized,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 Eq for NoneErrorimpl Eq for u16impl Eq for i8impl Eq for InvalidSequenceimpl<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<T> Eq for [T; 29] where
T: Eq,impl Eq for NonZeroUsizeimpl<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 u8x4impl Eq for FpCategoryimpl Eq for i8x2impl Eq for m8x2impl<T> Eq for [T; 24] where
T: Eq,impl Eq for u64x8impl<Ret, A> Eq for unsafe extern "C" fn(A) -> Retimpl<'a, B> Eq for Cow<'a, B> where
B: Eq + ToOwned + ?Sized,impl<T> Eq for LinkedList<T> where
T: Eq,impl Eq for ParseErrorimpl<K, V> Eq for BTreeMap<K, V> where
K: Eq,
V: Eq,impl Eq for Stringimpl<T> Eq for Rc<T> where
T: Eq + ?Sized,impl<T> Eq for Arc<T> where
T: Eq + ?Sized,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 Box<T> where
T: Eq + ?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