tag2upload_service_manager::prelude::cmp

Trait Eq

pub trait Eq: PartialEq { }

Expand description

Trait for comparisons corresponding to equivalence relations.

The primary difference to PartialEq is the additional requirement for reflexivity. A type that implements PartialEq guarantees that for all a, b and c:

symmetric: a == b implies b == a and a != b implies !(a == b)
transitive: a == b and b == c implies a == c

Eq, which builds on top of PartialEq also implies:

reflexive: a == a

This property cannot be checked by the compiler, and therefore Eq is a trait without 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.

Floating point types such as f32 and f64 implement only PartialEq but not Eq because NaN != NaN.

§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 extra 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 {}

Dyn Compatibility§

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Eq

Trait Eq Copy item path

§Derivable

§How can I implement Eq?

Dyn Compatibility§

Implementors§

impl Eq for JobStatus

impl Eq for ShownJobStatus

impl Eq for tag2upload_service_manager::db_migration::Outcome

impl Eq for AllowedClient

impl Eq for BadNamever

impl Eq for Interval

impl Eq for ProtocolVersion

impl Eq for WorkerPhase

impl Eq for WorkerFidelity

impl Eq for tag2upload_service_manager::prelude::IpAddr

impl Eq for IpNet

impl Eq for tag2upload_service_manager::prelude::fmt::Alignment

impl Eq for DebugAsHex

impl Eq for Sign

impl Eq for tag2upload_service_manager::prelude::io::ErrorKind

impl Eq for tag2upload_service_manager::prelude::io::SeekFrom

impl Eq for tag2upload_service_manager::prelude::oneshot::error::TryRecvError

impl Eq for tag2upload_service_manager::prelude::str::pattern::SearchStep

impl Eq for tag2upload_service_manager::prelude::cmp::Ordering

impl Eq for TryReserveErrorKind

impl Eq for AsciiChar

impl Eq for Infallible

impl Eq for FromBytesWithNulError

impl Eq for AtomicOrdering

impl Eq for SimdAlign

impl Eq for Ipv6MulticastScope

impl Eq for SocketAddr

impl Eq for FpCategory

impl Eq for IntErrorKind

impl Eq for core::slice::GetDisjointMutError

impl Eq for core::sync::atomic::Ordering

impl Eq for BacktraceStatus

impl Eq for VarError

impl Eq for Shutdown

impl Eq for BacktraceStyle

impl Eq for std::sync::mpsc::RecvTimeoutError

impl Eq for std::sync::mpsc::TryRecvError

impl Eq for AhoCorasickKind

impl Eq for aho_corasick::packed::api::MatchKind

impl Eq for aho_corasick::util::error::MatchErrorKind

impl Eq for aho_corasick::util::search::Anchored

impl Eq for aho_corasick::util::search::MatchKind

impl Eq for aho_corasick::util::search::StartKind

impl Eq for Action

impl Eq for anstyle_parse::state::definitions::State

impl Eq for AnsiColor

impl Eq for anstyle::color::Color

impl Eq for ParseAlphabetError

impl Eq for base64::decode::DecodeError

impl Eq for DecodeSliceError

impl Eq for EncodeSliceError

impl Eq for DecodePaddingMode

impl Eq for Tz

impl Eq for Colons

impl Eq for Fixed

impl Eq for Numeric

impl Eq for chrono::format::OffsetPrecision

impl Eq for Pad

impl Eq for ParseErrorKind

impl Eq for SecondsFormat

impl Eq for chrono::month::Month

impl Eq for RoundingError

impl Eq for chrono::weekday::Weekday

impl Eq for ArgPredicate

impl Eq for ValueHint

impl Eq for ContextKind

impl Eq for ContextValue

impl Eq for clap_builder::error::kind::ErrorKind

impl Eq for ValueSource

impl Eq for clap_builder::util::color::ColorChoice

impl Eq for colorchoice::ColorChoice

impl Eq for Expiration

impl Eq for cookie::parse::ParseError

impl Eq for SameSite

Trait Eq

§How can I implement `Eq`?