Trait gclient::ext::sp_core::sp_std::cmp::Eq

1.0.0 · source ·

pub trait Eq: PartialEq { }

Expand description

Trait for comparisons corresponding to equivalence relations.

This means, that in addition to a == b and a != b being strict inverses, the relation must be (for all a, b and c):

reflexive: a == a;
symmetric: a == b implies b == a (required by PartialEq as well); and
transitive: a == b and b == c implies a == c (required by PartialEq as well).

This property cannot be checked by the compiler, and therefore Eq implies PartialEq, and has no extra methods.

Violating this property is a logic error. The behavior resulting from a logic error is not specified, but users of the trait must ensure that such logic errors do not result in undefined behavior. This means that unsafe code must not rely on the correctness of these methods.

Implement Eq in addition to PartialEq if it’s guaranteed that PartialEq::eq(a, a) always returns true (reflexivity), in addition to the symmetric and transitive properties already required by PartialEq.

§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 {}

Object Safety§

This trait is not object safe.

Trait gclient::ext::sp_core::sp_std::cmp::Eq

§Derivable

§How can I implement Eq?

Object Safety§

Implementors§

impl Eq for ChargeError

impl Eq for ChargeResult

impl Eq for CounterType

impl Eq for LockId

impl Eq for gear_core::memory::AllocError

impl Eq for gear_core::memory::MemoryError

impl Eq for MemorySetupError

impl Eq for MessageDetails

impl Eq for DispatchKind

impl Eq for MessageWaitedType

impl Eq for GasReservationState

impl Eq for gear_core_errors::ExecutionError

impl Eq for ExtError

impl Eq for gear_core_errors::MemoryError

impl Eq for MessageError

impl Eq for ReservationError

impl Eq for ErrorReplyReason

impl Eq for ReplyCode

impl Eq for SignalCode

impl Eq for SimpleExecutionError

impl Eq for SimpleProgramCreationError

impl Eq for SuccessReplyReason

impl Eq for gsdk::backtrace::BacktraceStatus

impl Eq for DispatchStatus

impl Eq for DeriveError

impl Eq for DeriveJunction

impl Eq for SecretStringError

impl Eq for gclient::ext::sp_runtime::ArithmeticError

impl Eq for gclient::ext::sp_runtime::DigestItem

impl Eq for gclient::ext::sp_runtime::DispatchError

impl Eq for gclient::ext::sp_runtime::MultiSignature

impl Eq for MultiSigner

impl Eq for RuntimeString

impl Eq for StateVersion

impl Eq for gclient::ext::sp_runtime::TokenError

impl Eq for gclient::ext::sp_runtime::TransactionalError

impl Eq for gclient::ext::sp_runtime::generic::Era

impl Eq for gclient::ext::sp_runtime::legacy::byte_sized_error::DispatchError

impl Eq for HttpError

impl Eq for HttpRequestStatus

impl Eq for OffchainOverlayedChange

impl Eq for StorageKind

impl Eq for gclient::ext::sp_runtime::offchain::http::Error

impl Eq for gclient::ext::sp_runtime::offchain::http::Method

impl Eq for StorageRetrievalError

impl Eq for PathError

impl Eq for TypeDefPrimitive

impl Eq for MetaForm

impl Eq for PortableForm

impl Eq for InvalidTransaction

impl Eq for TransactionSource

impl Eq for TransactionValidityError

impl Eq for UnknownTransaction

impl Eq for TryReserveErrorKind

impl Eq for SearchStep

impl Eq for PublicError

impl Eq for Ss58AddressFormatRegistry

impl Eq for Void

impl Eq for ChildInfo

impl Eq for CallContext

impl Eq for Infallible

impl Eq for FpCategory

impl Eq for IntErrorKind

impl Eq for gclient::ext::sp_core::sp_std::sync::atomic::Ordering

impl Eq for RecvTimeoutError

impl Eq for gclient::ext::sp_core::sp_std::sync::mpsc::TryRecvError

impl Eq for gclient::ext::sp_core::sp_std::cmp::Ordering

impl Eq for webpki::error::Error

impl Eq for webpki::subject_name::ip_address::IpAddr

impl Eq for AsciiChar

impl Eq for core::fmt::Alignment

impl Eq for core::net::ip_addr::IpAddr

impl Eq for Ipv6MulticastScope

impl Eq for SocketAddr

impl Eq for std::backtrace::BacktraceStatus

§How can I implement `Eq`?