Trait no_std_compat2::cmp::Eq

pub trait Eq: PartialEq<Self> { }

Available on non-crate feature std only.

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 == b implies b == a; and
• transitive: a == b and b == c implies a == 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: &Self) -> bool {
        self.isbn == other.isbn
    }
}
impl Eq for Book {}

Implementors

impl Eq for AsciiChar

impl Eq for TryReserveErrorKind

impl Eq for Infallible

impl Eq for no_std_compat2::fmt::Alignment

impl Eq for IpAddr

impl Eq for Ipv6MulticastScope

impl Eq for SocketAddr

impl Eq for FpCategory

impl Eq for IntErrorKind

impl Eq for SearchStep

impl Eq for no_std_compat2::sync::atomic::Ordering

impl Eq for no_std_compat2::cmp::Ordering

impl Eq for Which

impl Eq for BacktraceStatus

impl Eq for VarError

impl Eq for SeekFrom

impl Eq for ErrorKind

impl Eq for Shutdown

impl Eq for BacktraceStyle

impl Eq for RecvTimeoutError

impl Eq for TryRecvError

impl Eq for hashbrown::TryReserveError

impl Eq for bool

impl Eq for char

impl Eq for i8

impl Eq for i16

impl Eq for i32

impl Eq for i64

impl Eq for i128

impl Eq for isize

impl Eq for !

impl Eq for str

impl Eq for u8

impl Eq for u16

impl Eq for u32

impl Eq for u64

impl Eq for u128

impl Eq for ()

impl Eq for usize

impl Eq for AllocError

impl Eq for Layout

impl Eq for LayoutError

impl Eq for TypeId

impl Eq for CpuidResult

impl Eq for CharTryFromError

impl Eq for DecodeUtf16Error

impl Eq for ParseCharError

impl Eq for TryFromCharError

impl Eq for no_std_compat2::collections::TryReserveError

impl Eq for no_std_compat2::ffi::CStr

impl Eq for no_std_compat2::ffi::CString

impl Eq for FromBytesUntilNulError

impl Eq for no_std_compat2::ffi::FromBytesWithNulError

impl Eq for FromVecWithNulError

impl Eq for no_std_compat2::ffi::IntoStringError

impl Eq for no_std_compat2::ffi::NulError

impl Eq for Error

impl Eq for PhantomPinned

impl Eq for Assume

impl Eq for AddrParseError

impl Eq for Ipv4Addr

impl Eq for Ipv6Addr

impl Eq for SocketAddrV4

impl Eq for SocketAddrV6

impl Eq for NonZeroI8

impl Eq for NonZeroI16

impl Eq for NonZeroI32

impl Eq for NonZeroI64

impl Eq for NonZeroI128

impl Eq for NonZeroIsize

impl Eq for NonZeroU8

impl Eq for NonZeroU16

impl Eq for NonZeroU32

impl Eq for NonZeroU64

impl Eq for NonZeroU128

impl Eq for NonZeroUsize

impl Eq for ParseFloatError

impl Eq for ParseIntError

impl Eq for TryFromIntError

impl Eq for RangeFull

impl Eq for no_std_compat2::path::Components<'_>

impl Eq for no_std_compat2::path::Path

impl Eq for no_std_compat2::path::PathBuf

Available on crate feature alloc only.

impl Eq for no_std_compat2::path::StripPrefixError

impl Eq for no_std_compat2::ptr::Alignment

impl Eq for ParseBoolError

impl Eq for Utf8Error

impl Eq for FromUtf8Error

impl Eq for String

impl Eq for Duration

impl Eq for TryFromFloatSecsError

impl Eq for core::ffi::c_str::CStr

impl Eq for OsStr

impl Eq for OsString

impl Eq for FileType

impl Eq for Permissions

impl Eq for UCred

impl Eq for std::path::Components<'_>

impl Eq for std::path::Path

impl Eq for std::path::PathBuf

impl Eq for std::path::StripPrefixError

impl Eq for ExitStatus

impl Eq for ExitStatusError

impl Eq for Output

impl Eq for WaitTimeoutResult

impl Eq for RecvError

impl Eq for AccessError

impl Eq for ThreadId

impl Eq for Instant

impl Eq for SystemTime

impl Eq for cstr_core::CString

impl Eq for cstr_core::FromBytesWithNulError

impl Eq for cstr_core::IntoStringError

impl Eq for cstr_core::NulError

impl Eq for UnixStr

impl Eq for UnixString

Available on crate feature alloc only.

impl<'a> Eq for no_std_compat2::path::Component<'a>

impl<'a> Eq for std::path::Component<'a>

impl<'a> Eq for Prefix<'a>

impl<'a> Eq for Location<'a>

impl<'a> Eq for Utf8Chunk<'a>

impl<'a> Eq for PrefixComponent<'a>

impl<A> Eq for &Awhere A: Eq + ?Sized,

impl<A> Eq for &mut Awhere A: Eq + ?Sized,

impl<B> Eq for Cow<'_, B>where B: Eq + ToOwned + ?Sized,

impl<B, C> Eq for ControlFlow<B, C>where B: Eq, C: Eq,

impl<Dyn> Eq for DynMetadata<Dyn>where Dyn: ?Sized,

impl<F> Eq for Fwhere F: FnPtr,

impl<H> Eq for BuildHasherDefault<H>

impl<Idx> Eq for Range<Idx>where Idx: Eq,

impl<Idx> Eq for RangeFrom<Idx>where Idx: Eq,

impl<Idx> Eq for RangeInclusive<Idx>where Idx: Eq,

impl<Idx> Eq for RangeTo<Idx>where Idx: Eq,

impl<Idx> Eq for RangeToInclusive<Idx>where Idx: Eq,

impl<K, V, A> Eq for BTreeMap<K, V, A>where K: Eq, V: Eq, A: Allocator + Clone,

impl<K, V, S> Eq for std::collections::hash::map::HashMap<K, V, S>where K: Eq + Hash, V: Eq, S: BuildHasher,

impl<K, V, S, A> Eq for no_std_compat2::collections::HashMap<K, V, S, A>where K: Eq + Hash, V: Eq, S: BuildHasher, A: Allocator + Clone,

impl<P> Eq for Pin<P>where P: Deref, <P as Deref>::Target: Eq,

impl<T> Eq for Bound<T>where T: Eq,

impl<T> Eq for Option<T>where T: Eq,

impl<T> Eq for Poll<T>where T: Eq,

impl<T> Eq for TrySendError<T>where T: Eq,

impl<T> Eq for *const Twhere T: ?Sized,

impl<T> Eq for *mut Twhere T: ?Sized,

impl<T> Eq for [T]where T: Eq,

impl<T> Eq for (T₁, T₂, …, Tₙ)where T: Eq + ?Sized,

This trait is implemented for tuples up to twelve items long.

impl<T> Eq for Cell<T>where T: Eq + Copy,

impl<T> Eq for no_std_compat2::cell::OnceCell<T>where T: Eq,

impl<T> Eq for RefCell<T>where T: Eq + ?Sized,

impl<T> Eq for PhantomData<T>where T: ?Sized,

impl<T> Eq for Discriminant<T>

impl<T> Eq for ManuallyDrop<T>where T: Eq + ?Sized,

impl<T> Eq for Saturating<T>where T: Eq,

impl<T> Eq for Wrapping<T>where T: Eq,

impl<T> Eq for NonNull<T>where T: ?Sized,

impl<T> Eq for Rc<T>where T: Eq + ?Sized,

impl<T> Eq for Arc<T>where T: Eq + ?Sized,

impl<T> Eq for Cursor<T>where T: Eq,

impl<T> Eq for SendError<T>where T: Eq,

impl<T> Eq for OnceLock<T>where T: Eq,

impl<T> Eq for Reverse<T>where T: Eq,

impl<T> Eq for OnceCell<T>where T: Eq,

impl<T, A> Eq for BTreeSet<T, A>where T: Eq, A: Allocator + Clone,

impl<T, A> Eq for LinkedList<T, A>where T: Eq, A: Allocator,

impl<T, A> Eq for VecDeque<T, A>where T: Eq, A: Allocator,

impl<T, A> Eq for Box<T, A>where T: Eq + ?Sized, A: Allocator,

impl<T, A> Eq for Vec<T, A>where T: Eq, A: Allocator,

impl<T, E> Eq for Result<T, E>where T: Eq, E: Eq,

impl<T, S> Eq for std::collections::hash::set::HashSet<T, S>where T: Eq + Hash, S: BuildHasher,

impl<T, S, A> Eq for no_std_compat2::collections::HashSet<T, S, A>where T: Eq + Hash, S: BuildHasher, A: Allocator + Clone,

impl<T, const N: usize> Eq for [T; N]where T: Eq,

impl<T, const N: usize> Eq for Simd<T, N>where LaneCount<N>: SupportedLaneCount, T: SimdElement + Eq,

impl<Y, R> Eq for GeneratorState<Y, R>where Y: Eq, R: Eq,