Trait nom::lib::std::hash::Hash1.0.0[][src]

pub trait Hash {
    pub fn hash<H>(&self, state: &mut H)
    where
        H: Hasher
; pub 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

pub fn hash<H>(&self, state: &mut H) where
    H: Hasher
[src]

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

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

Feeds a slice of this type into the given Hasher.

This method is meant as a convenience, but its implementation is also explicitly left unspecified. It isn’t guaranteed to be equivalent to repeated calls of hash and implementations of Hash should keep that in mind and call hash themselves if the slice isn’t treated as a whole unit in the PartialEq implementation.

For example, a VecDeque implementation might naïvely call as_slices and then hash_slice on each slice, but this is wrong since the two slices can change with a call to make_contiguous without affecting the PartialEq result. Since these slices aren’t treated as singular units, and instead part of a larger deque, this method cannot be used.

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 IpAddr[src]

impl Hash for Ipv6MulticastScope[src]

impl Hash for SocketAddrV6[src]

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

impl Hash for Ipv4Addr[src]

impl Hash for SocketAddrV4[src]

impl Hash for CStr[src]

impl Hash for ErrorKind[src]

impl Hash for Instant[src]

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

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

impl Hash for PathBuf[src]

impl Hash for Ipv6Addr[src]

impl Hash for Path[src]

impl Hash for UCred[src]

impl Hash for FileType[src]

impl Hash for OsStr[src]

impl Hash for SocketAddr[src]

impl Hash for OsString[src]

impl Hash for SystemTime[src]

impl Hash for ThreadId[src]

impl Hash for CString[src]

impl Hash for ![src]

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

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

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

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

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

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

impl Hash for NonZeroU32[src]

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

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

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

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

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

impl<T> Hash for PhantomData<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 Hash for u8[src]

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

impl Hash for NonZeroI64[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<Ret, A, B, C, D> Hash for unsafe fn(A, B, C, D) -> Ret[src]

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

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

impl Hash for u32[src]

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

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

impl Hash for i16[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, C, D, E> Hash for fn(A, B, C, D, E) -> Ret[src]

impl Hash for NonZeroIsize[src]

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

impl Hash for NonZeroI128[src]

impl Hash for u128[src]

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

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

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

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

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

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

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

impl<'_, T> Hash for &'_ mut T where
    T: 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 Hash for ()[src]

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

impl Hash for i128[src]

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

impl Hash for i8[src]

impl Hash for NonZeroU64[src]

impl Hash for NonZeroU8[src]

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

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

impl<Dyn> Hash for DynMetadata<Dyn> where
    Dyn: ?Sized
[src]

impl Hash for i64[src]

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

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

impl<Ret, A, B> Hash for fn(A, B) -> 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 Hash for u64[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> Hash for unsafe extern "C" fn(A, B, C, D) -> Ret[src]

impl Hash for isize[src]

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

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

impl Hash for NonZeroU128[src]

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

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

impl Hash for NonZeroI8[src]

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

impl Hash for NonZeroI32[src]

impl<Ret, A, B, C, D, E, F> Hash for extern "C" fn(A, B, C, D, E, F) -> 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<Ret, A> Hash for extern "C" fn(A) -> Ret[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 NonZeroI16[src]

impl<T> Hash for NonNull<T> where
    T: ?Sized
[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> Hash for extern "C" fn(A, B) -> Ret[src]

impl Hash for NonZeroU16[src]

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

impl Hash for bool[src]

impl Hash for u16[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 usize[src]

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

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

impl<T> Hash for *const T where
    T: ?Sized
[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<Ret, A, B, C, D> Hash for unsafe extern "C" fn(A, B, C, D, ...) -> Ret[src]

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

impl Hash for i32[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, E, F, G, H, I> Hash for unsafe extern "C" fn(A, B, C, D, E, F, G, H, I) -> Ret[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, 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, E, F, G> Hash for unsafe extern "C" 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 Rc<T> where
    T: Hash + ?Sized
[src]

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

Loading content...

Implementors

impl Hash for nom::error::ErrorKind[src]

impl Hash for nom::lib::std::cmp::Ordering[src]

impl Hash for Infallible1.44.0[src]

impl Hash for Error[src]

impl Hash for RangeFull[src]

impl Hash for NoneError[src]

impl Hash for String[src]

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

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

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

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

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

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

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

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

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

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

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

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

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

impl<T> Hash for Discriminant<T>1.21.0[src]

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

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

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

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

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

Loading content...