Expand description
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.
This trait can be used with #[derive]
. When derive
d, 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.
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 {}
Run
sourceAvailable on Windows only.
sourceAvailable on Windows only.
sourceimpl<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,
sourceimpl<B, C, D, E, F, G, H, I, J, K, L> Eq for (B, C, D, E, F, G, H, I, J, K, L) where
B: Eq,
C: Eq,
D: Eq,
E: Eq,
F: Eq,
G: Eq,
H: Eq,
I: Eq,
J: Eq,
K: Eq,
L: Eq + ?Sized,
sourceimpl<C, D, E, F, G, H, I, J, K, L> Eq for (C, D, E, F, G, H, I, J, K, L) where
C: Eq,
D: Eq,
E: Eq,
F: Eq,
G: Eq,
H: Eq,
I: Eq,
J: Eq,
K: Eq,
L: Eq + ?Sized,
sourceimpl<D, E, F, G, H, I, J, K, L> Eq for (D, E, F, G, H, I, J, K, L) where
D: Eq,
E: Eq,
F: Eq,
G: Eq,
H: Eq,
I: Eq,
J: Eq,
K: Eq,
L: Eq + ?Sized,
sourceimpl<E, F, G, H, I, J, K, L> Eq for (E, F, G, H, I, J, K, L) where
E: Eq,
F: Eq,
G: Eq,
H: Eq,
I: Eq,
J: Eq,
K: Eq,
L: Eq + ?Sized,
sourceimpl<F, G, H, I, J, K, L> Eq for (F, G, H, I, J, K, L) where
F: Eq,
G: Eq,
H: Eq,
I: Eq,
J: Eq,
K: Eq,
L: Eq + ?Sized,
sourceimpl<G, H, I, J, K, L> Eq for (G, H, I, J, K, L) where
G: Eq,
H: Eq,
I: Eq,
J: Eq,
K: Eq,
L: Eq + ?Sized,
sourceimpl<H, I, J, K, L> Eq for (H, I, J, K, L) where
H: Eq,
I: Eq,
J: Eq,
K: Eq,
L: Eq + ?Sized,
sourceimpl<I, J, K, L> Eq for (I, J, K, L) where
I: Eq,
J: Eq,
K: Eq,
L: Eq + ?Sized,
1.4.0 · sourceimpl<Ret> Eq for extern "C" fn() -> Ret
1.4.0 · sourceimpl<Ret> Eq for unsafe extern "C" fn() -> Ret
1.4.0 · sourceimpl<Ret, A> Eq for extern "C" fn(A) -> Ret
1.4.0 · sourceimpl<Ret, A> Eq for extern "C" fn(A, ...) -> Ret
1.4.0 · sourceimpl<Ret, A> Eq for unsafe fn(A) -> Ret
1.4.0 · sourceimpl<Ret, A> Eq for unsafe extern "C" fn(A) -> Ret
1.4.0 · sourceimpl<Ret, A> Eq for unsafe extern "C" fn(A, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B> Eq for fn(A, B) -> Ret
1.4.0 · sourceimpl<Ret, A, B> Eq for extern "C" fn(A, B) -> Ret
1.4.0 · sourceimpl<Ret, A, B> Eq for extern "C" fn(A, B, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B> Eq for unsafe fn(A, B) -> Ret
1.4.0 · sourceimpl<Ret, A, B> Eq for unsafe extern "C" fn(A, B) -> Ret
1.4.0 · sourceimpl<Ret, A, B> Eq for unsafe extern "C" fn(A, B, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C> Eq for fn(A, B, C) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C> Eq for extern "C" fn(A, B, C) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C> Eq for extern "C" fn(A, B, C, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C> Eq for unsafe fn(A, B, C) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C> Eq for unsafe extern "C" fn(A, B, C) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C> Eq for unsafe extern "C" fn(A, B, C, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D> Eq for fn(A, B, C, D) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D> Eq for extern "C" fn(A, B, C, D) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D> Eq for extern "C" fn(A, B, C, D, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D> Eq for unsafe fn(A, B, C, D) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D> Eq for unsafe extern "C" fn(A, B, C, D) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D> Eq for unsafe extern "C" fn(A, B, C, D, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E> Eq for fn(A, B, C, D, E) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E> Eq for extern "C" fn(A, B, C, D, E) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E> Eq for extern "C" fn(A, B, C, D, E, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E> Eq for unsafe fn(A, B, C, D, E) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E> Eq for unsafe extern "C" fn(A, B, C, D, E) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E> Eq for unsafe extern "C" fn(A, B, C, D, E, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F> Eq for fn(A, B, C, D, E, F) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F> Eq for extern "C" fn(A, B, C, D, E, F) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F> Eq for extern "C" fn(A, B, C, D, E, F, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F> Eq for unsafe fn(A, B, C, D, E, F) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F> Eq for unsafe extern "C" fn(A, B, C, D, E, F) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F> Eq for unsafe extern "C" fn(A, B, C, D, E, F, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G> Eq for fn(A, B, C, D, E, F, G) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G> Eq for extern "C" fn(A, B, C, D, E, F, G) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G> Eq for extern "C" fn(A, B, C, D, E, F, G, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G> Eq for unsafe fn(A, B, C, D, E, F, G) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H> Eq for fn(A, B, C, D, E, F, G, H) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H> Eq for extern "C" fn(A, B, C, D, E, F, G, H) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H> Eq for extern "C" fn(A, B, C, D, E, F, G, H, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H> Eq for unsafe fn(A, B, C, D, E, F, G, H) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H> Eq for unsafe extern "C" fn(A, B, C, D, E, F, G, H, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H, I> Eq for fn(A, B, C, D, E, F, G, H, I) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H, I> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H, I> Eq for extern "C" fn(A, B, C, D, E, F, G, H, I, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H, I> Eq for unsafe fn(A, B, C, D, E, F, G, H, I) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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, ...) -> Ret
1.4.0 · sourceimpl<Ret, A, B, C, D, E, F, G, H, I, J> Eq for fn(A, B, C, D, E, F, G, H, I, J) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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, ...) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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, ...) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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, ...) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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, ...) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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, ...) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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) -> Ret
1.4.0 · sourceimpl<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, ...) -> Ret