1.0.0[][src]Trait epilog::unify::Hash

pub trait Hash {
    fn hash<H>(&self, state: &mut H)
    where
        H: Hasher
; fn hash_slice<H>(data: &[Self], state: &mut H)
    where
        H: Hasher
, { ... } }

A hashable type.

Types implementing Hash are able to be hashed with an instance of Hasher.

Implementing Hash

You can derive Hash with #[derive(Hash)] if all fields implement Hash. The resulting hash will be the combination of the values from calling hash on each field.

#[derive(Hash)]
struct Rustacean {
    name: String,
    country: String,
}

If you need more control over how a value is hashed, you can of course implement the Hash trait yourself:

use std::hash::{Hash, Hasher};

struct Person {
    id: u32,
    name: String,
    phone: u64,
}

impl Hash for Person {
    fn hash<H: Hasher>(&self, state: &mut H) {
        self.id.hash(state);
        self.phone.hash(state);
    }
}

Hash and Eq

When implementing both Hash and Eq, it is important that the following property holds:

k1 == k2 -> hash(k1) == hash(k2)

In other words, if two keys are equal, their hashes must also be equal. HashMap and HashSet both rely on this behavior.

Thankfully, you won't need to worry about upholding this property when deriving both Eq and Hash with #[derive(PartialEq, Eq, Hash)].

Required methods

fn hash<H>(&self, state: &mut H) where
    H: Hasher

Feeds this value into the given Hasher.

Examples

use std::collections::hash_map::DefaultHasher;
use std::hash::{Hash, Hasher};

let mut hasher = DefaultHasher::new();
7920.hash(&mut hasher);
println!("Hash is {:x}!", hasher.finish());
Loading content...

Provided methods

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher
1.3.0

Feeds a slice of this type into the given Hasher.

Examples

use std::collections::hash_map::DefaultHasher;
use std::hash::{Hash, Hasher};

let mut hasher = DefaultHasher::new();
let numbers = [6, 28, 496, 8128];
Hash::hash_slice(&numbers, &mut hasher);
println!("Hash is {:x}!", hasher.finish());
Loading content...

Implementations on Foreign Types

impl Hash for CString[src]

impl Hash for Path[src]

impl Hash for FileType[src]

impl Hash for Ipv6MulticastScope[src]

impl Hash for SocketAddr[src]

impl Hash for IpAddr[src]

impl Hash for Ipv6Addr[src]

impl Hash for Instant[src]

impl Hash for SystemTime[src]

impl<'a> Hash for Prefix<'a>[src]

impl<'_> Hash for PrefixComponent<'_>[src]

impl Hash for OsString[src]

impl<'a> Hash for Component<'a>[src]

impl Hash for SocketAddrV6[src]

impl Hash for PathBuf[src]

impl Hash for OsStr[src]

impl Hash for ThreadId[src]

impl Hash for CStr[src]

impl Hash for SocketAddrV4[src]

impl Hash for Ipv4Addr[src]

impl Hash for ErrorKind[src]

impl<P> Hash for Pin<P> where
    P: Deref,
    <P as Deref>::Target: Hash
[src]

impl<Ret, A, B, C, D, E, F, G> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G) -> Ret[src]

impl Hash for u16[src]

impl<Ret, A, B, C, D, E, F, G, H, I> Hash for unsafe fn(A, B, C, D, E, F, G, H, I) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, ...) -> Ret[src]

impl<Ret, A, B> Hash for extern "C" fn(A, B, ...) -> Ret[src]

impl Hash for NonZeroI32[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K> Hash for extern "C" fn(A, B, C, D, E, F, G, H, I, J, K) -> Ret[src]

impl<'_, T> Hash for &'_ T where
    T: Hash + ?Sized
[src]

impl Hash for NonZeroU32[src]

impl<Ret, A, B, C, D, E, F, G, H, I> Hash for fn(A, B, C, D, E, F, G, H, I) -> Ret[src]

impl<Ret, A, B, C> Hash for unsafe extern "C" fn(A, B, C, ...) -> Ret[src]

impl<Ret, A> Hash for unsafe extern "C" fn(A, ...) -> Ret[src]

impl<A, B, C, D, E, F, G, H, I, J, K, L> Hash for (A, B, C, D, E, F, G, H, I, J, K, L) where
    A: Hash,
    B: Hash,
    C: Hash,
    D: Hash,
    E: Hash,
    F: Hash,
    G: Hash,
    H: Hash,
    I: Hash,
    J: Hash,
    K: Hash,
    L: Hash + ?Sized
[src]

impl<Ret, A, B, C, D, E, F, G, H> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, ...) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H> Hash for extern "C" fn(A, B, C, D, E, F, G, H, ...) -> Ret[src]

impl<Ret, A, B, C, D> Hash for extern "C" fn(A, B, C, D) -> Ret[src]

impl Hash for PhantomPinned[src]

impl Hash for NonZeroI8[src]

impl Hash for NoneError[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, K) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K> Hash for fn(A, B, C, D, E, F, G, H, I, J, K) -> Ret[src]

impl<T> Hash for Wrapping<T> where
    T: Hash
[src]

impl<A, B, C, D, E, F, G> Hash for (A, B, C, D, E, F, G) where
    A: Hash,
    B: Hash,
    C: Hash,
    D: Hash,
    E: Hash,
    F: Hash,
    G: Hash + ?Sized
[src]

impl<Ret, A, B, C, D, E> Hash for extern "C" fn(A, B, C, D, E) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I) -> Ret[src]

impl<Idx> Hash for RangeTo<Idx> where
    Idx: Hash
[src]

impl<A, B, C, D, E> Hash for (A, B, C, D, E) where
    A: Hash,
    B: Hash,
    C: Hash,
    D: Hash,
    E: Hash + ?Sized
[src]

impl<Ret, A, B, C, D, E, F, G> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, ...) -> Ret[src]

impl<Ret, A, B, C, D> Hash for unsafe extern "C" fn(A, B, C, D) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G> Hash for unsafe fn(A, B, C, D, E, F, G) -> Ret[src]

impl<Ret, A, B, C> Hash for extern "C" fn(A, B, C) -> Ret[src]

impl Hash for NonZeroU128[src]

impl<Ret, A, B, C, D, E, F, G> Hash for extern "C" fn(A, B, C, D, E, F, G, ...) -> Ret[src]

impl Hash for ()[src]

impl Hash for i128[src]

impl<Ret, A, B, C, D, E, F, G, H> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I> Hash for extern "C" fn(A, B, C, D, E, F, G, H, I, ...) -> Ret[src]

impl<Ret, A, B, C, D, E> Hash for unsafe fn(A, B, C, D, E) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Hash for unsafe fn(A, B, C, D, E, F, G, H, I, J, K, L) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Hash for extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, L) -> Ret[src]

impl<T> Hash for NonNull<T> where
    T: ?Sized
[src]

impl<T> Hash for *mut T where
    T: ?Sized
[src]

impl Hash for NonZeroU8[src]

impl Hash for i32[src]

impl Hash for Error[src]

impl Hash for i64[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J> Hash for extern "C" fn(A, B, C, D, E, F, G, H, I, J) -> Ret[src]

impl<Idx> Hash for RangeToInclusive<Idx> where
    Idx: Hash
[src]

impl Hash for Ordering[src]

impl<Ret, A, B, C, D, E> Hash for extern "C" fn(A, B, C, D, E, ...) -> Ret[src]

impl<Ret, A, B, C, D> Hash for extern "C" fn(A, B, C, D, ...) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I> Hash for extern "C" fn(A, B, C, D, E, F, G, H, I) -> Ret[src]

impl Hash for char[src]

impl<T> Hash for [T] where
    T: Hash
[src]

impl Hash for Ordering[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Hash for fn(A, B, C, D, E, F, G, H, I, J, K, L) -> Ret[src]

impl Hash for TypeId[src]

impl<A, B, C, D> Hash for (A, B, C, D) where
    A: Hash,
    B: Hash,
    C: Hash,
    D: Hash + ?Sized
[src]

impl<Ret, A, B> Hash for unsafe extern "C" fn(A, B) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J> Hash for extern "C" fn(A, B, C, D, E, F, G, H, I, J, ...) -> Ret[src]

impl<Ret, A, B, C, D> Hash for fn(A, B, C, D) -> Ret[src]

impl<Ret, A, B, C, D, E> Hash for unsafe extern "C" fn(A, B, C, D, E, ...) -> Ret[src]

impl<Ret, A, B, C, D, E, F> Hash for unsafe fn(A, B, C, D, E, F) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, ...) -> Ret[src]

impl Hash for ![src]

impl<'_, T> Hash for &'_ mut T where
    T: Hash + ?Sized
[src]

impl<A, B, C, D, E, F, G, H> Hash for (A, B, C, D, E, F, G, H) where
    A: Hash,
    B: Hash,
    C: Hash,
    D: Hash,
    E: Hash,
    F: Hash,
    G: Hash,
    H: Hash + ?Sized
[src]

impl<Ret> Hash for fn() -> Ret[src]

impl<T> Hash for *const T where
    T: ?Sized
[src]

impl<Ret, A, B, C, D, E, F, G, H> Hash for unsafe fn(A, B, C, D, E, F, G, H) -> Ret[src]

impl<A, B, C, D, E, F, G, H, I, J, K> Hash for (A, B, C, D, E, F, G, H, I, J, K) where
    A: Hash,
    B: Hash,
    C: Hash,
    D: Hash,
    E: Hash,
    F: Hash,
    G: Hash,
    H: Hash,
    I: Hash,
    J: Hash,
    K: Hash + ?Sized
[src]

impl<Ret, A, B, C, D> Hash for unsafe extern "C" fn(A, B, C, D, ...) -> Ret[src]

impl<Ret, A> Hash for fn(A) -> Ret[src]

impl<Ret> Hash for unsafe extern "C" fn() -> Ret[src]

impl Hash for u32[src]

impl Hash for i8[src]

impl<Ret, A, B, C, D, E, F, G, H> Hash for extern "C" fn(A, B, C, D, E, F, G, H) -> Ret[src]

impl Hash for NonZeroU64[src]

impl<T> Hash for ManuallyDrop<T> where
    T: Hash + ?Sized
[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K> Hash for extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, ...) -> Ret[src]

impl<Idx> Hash for Range<Idx> where
    Idx: Hash
[src]

impl Hash for NonZeroUsize[src]

impl<T> Hash for Bound<T> where
    T: Hash
[src]

impl<Ret, A, B, C> Hash for unsafe extern "C" fn(A, B, C) -> Ret[src]

impl<Ret, A, B, C> Hash for unsafe fn(A, B, C) -> Ret[src]

impl<Y, R> Hash for GeneratorState<Y, R> where
    R: Hash,
    Y: Hash
[src]

impl<Ret, A, B, C, D, E, F> Hash for unsafe extern "C" fn(A, B, C, D, E, F, ...) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G> Hash for extern "C" fn(A, B, C, D, E, F, G) -> Ret[src]

impl<A> Hash for (A,) where
    A: Hash + ?Sized
[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J> Hash for unsafe fn(A, B, C, D, E, F, G, H, I, J) -> Ret[src]

impl<A, B> Hash for (A, B) where
    A: Hash,
    B: Hash + ?Sized
[src]

impl Hash for Duration[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, L) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G> Hash for fn(A, B, C, D, E, F, G) -> Ret[src]

impl<Ret, A, B, C, D, E, F> Hash for unsafe extern "C" fn(A, B, C, D, E, F) -> Ret[src]

impl<T> Hash for Reverse<T> where
    T: Hash
[src]

impl<Ret, A> Hash for unsafe fn(A) -> Ret[src]

impl<T, E> Hash for Result<T, E> where
    E: Hash,
    T: Hash
[src]

impl Hash for u128[src]

impl<Ret, A, B> Hash for unsafe extern "C" fn(A, B, ...) -> Ret[src]

impl Hash for NonZeroI128[src]

impl<Idx> Hash for RangeInclusive<Idx> where
    Idx: Hash
[src]

impl<Ret, A, B, C> Hash for fn(A, B, C) -> Ret[src]

impl<Ret, A, B, C, D, E, F> Hash for fn(A, B, C, D, E, F) -> Ret[src]

impl Hash for RangeFull[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, ...) -> Ret[src]

impl<Ret, A, B, C> Hash for extern "C" fn(A, B, C, ...) -> Ret[src]

impl<Ret, A, B, C, D, E> Hash for unsafe extern "C" fn(A, B, C, D, E) -> Ret[src]

impl<T> Hash for Discriminant<T>[src]

impl<T> Hash for Poll<T> where
    T: Hash
[src]

impl Hash for str[src]

impl<T> Hash for Option<T> where
    T: Hash
[src]

impl<Ret, A, B> Hash for fn(A, B) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H> Hash for fn(A, B, C, D, E, F, G, H) -> Ret[src]

impl Hash for NonZeroI64[src]

impl<Ret, A, B, C, D> Hash for unsafe fn(A, B, C, D) -> Ret[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, L, ...) -> Ret[src]

impl<Ret, A, B, C, D, E> Hash for fn(A, B, C, D, E) -> Ret[src]

impl Hash for i16[src]

impl<Ret> Hash for extern "C" fn() -> Ret[src]

impl<A, B, C, D, E, F> Hash for (A, B, C, D, E, F) where
    A: Hash,
    B: Hash,
    C: Hash,
    D: Hash,
    E: Hash,
    F: Hash + ?Sized
[src]

impl<Ret> Hash for unsafe fn() -> Ret[src]

impl<Ret, A> Hash for extern "C" fn(A) -> Ret[src]

impl<Ret, A, B> Hash for unsafe fn(A, B) -> Ret[src]

impl<T> Hash for PhantomData<T> where
    T: ?Sized
[src]

impl<Ret, A> Hash for unsafe extern "C" fn(A) -> Ret[src]

impl Hash for bool[src]

impl<A, B, C, D, E, F, G, H, I, J> Hash for (A, B, C, D, E, F, G, H, I, J) where
    A: Hash,
    B: Hash,
    C: Hash,
    D: Hash,
    E: Hash,
    F: Hash,
    G: Hash,
    H: Hash,
    I: Hash,
    J: Hash + ?Sized
[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K> Hash for unsafe fn(A, B, C, D, E, F, G, H, I, J, K) -> Ret[src]

impl Hash for NonZeroI16[src]

impl<Ret, A> Hash for extern "C" fn(A, ...) -> Ret[src]

impl Hash for u64[src]

impl Hash for isize[src]

impl Hash for NonZeroIsize[src]

impl<Ret, A, B, C, D, E, F> Hash for extern "C" fn(A, B, C, D, E, F, ...) -> Ret[src]

impl Hash for usize[src]

impl<Idx> Hash for RangeFrom<Idx> where
    Idx: Hash
[src]

impl<A, B, C> Hash for (A, B, C) where
    A: Hash,
    B: Hash,
    C: Hash + ?Sized
[src]

impl Hash for NonZeroU16[src]

impl<Ret, A, B, C, D, E, F> Hash for extern "C" fn(A, B, C, D, E, F) -> Ret[src]

impl<A, B, C, D, E, F, G, H, I> Hash for (A, B, C, D, E, F, G, H, I) where
    A: Hash,
    B: Hash,
    C: Hash,
    D: Hash,
    E: Hash,
    F: Hash,
    G: Hash,
    H: Hash,
    I: Hash + ?Sized
[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J, K, L> Hash for extern "C" fn(A, B, C, D, E, F, G, H, I, J, K, L, ...) -> Ret[src]

impl<Ret, A, B> Hash for extern "C" fn(A, B) -> Ret[src]

impl Hash for u8[src]

impl<Ret, A, B, C, D, E, F, G, H, I, J> Hash for fn(A, B, C, D, E, F, G, H, I, J) -> Ret[src]

impl<const N: usize, T> Hash for [T; N] where
    T: Hash,
    [T; N]: LengthAtMost32
[src]

impl<T> Hash for Arc<T> where
    T: Hash + ?Sized
[src]

impl<T> Hash for BTreeSet<T> where
    T: Hash
[src]

impl Hash for String[src]

impl<A> Hash for VecDeque<A> where
    A: Hash
[src]

impl<T> Hash for Vec<T> where
    T: Hash
[src]

impl<K, V> Hash for BTreeMap<K, V> where
    K: Hash,
    V: Hash
[src]

impl<T> Hash for Rc<T> where
    T: Hash + ?Sized
[src]

impl<T> Hash for LinkedList<T> where
    T: Hash
[src]

impl<T> Hash for Box<T> where
    T: Hash + ?Sized
[src]

Loading content...

Implementors

impl<'_, B> Hash for Cow<'_, B> where
    B: Hash + ToOwned + ?Sized
[src]

impl<L: Hash, V: Hash> Hash for Term<L, V>[src]

impl<V: Hash> Hash for Var<V>[src]

Loading content...