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());

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());

Trait nom::lib::std::hash::Hash⎘1.0.0[−][src]

Implementing Hash

Hash and Eq

Required methods

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

Examples

Provided methods

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

Examples

Implementations on Foreign Types

impl Hash for IpAddr[src]

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

impl Hash for Ipv6MulticastScope[src]

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

impl Hash for SocketAddrV6[src]

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

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

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

impl Hash for Ipv4Addr[src]

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

impl Hash for SocketAddrV4[src]

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

impl Hash for CStr[src]

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

impl Hash for ErrorKind[src]

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

impl Hash for Instant[src]

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

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

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

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

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

impl Hash for PathBuf[src]

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

impl Hash for Ipv6Addr[src]

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

impl Hash for Path[src]

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

impl Hash for UCred[src]

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

impl Hash for FileType[src]

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

impl Hash for OsStr[src]

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

impl Hash for SocketAddr[src]

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

impl Hash for OsString[src]

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

impl Hash for SystemTime[src]

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

impl Hash for ThreadId[src]

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

impl Hash for CString[src]

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

impl Hash for ![src]

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

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

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

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

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

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

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

impl Hash for char[src]

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

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

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

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

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

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

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

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

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

impl Hash for Duration[src]

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

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

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

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

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

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

Implementing `Hash`

`Hash` and `Eq`

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

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

`impl Hash for IpAddr`[src]

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

`impl Hash for Ipv6MulticastScope`[src]

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

`impl Hash for SocketAddrV6`[src]

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

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

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

`impl Hash for Ipv4Addr`[src]

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

`impl Hash for SocketAddrV4`[src]

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

`impl Hash for CStr`[src]

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

`impl Hash for ErrorKind`[src]

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

`impl Hash for Instant`[src]

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

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

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

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

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

`impl Hash for PathBuf`[src]

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

`impl Hash for Ipv6Addr`[src]

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

`impl Hash for Path`[src]

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

`impl Hash for UCred`[src]

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

`impl Hash for FileType`[src]

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

`impl Hash for OsStr`[src]

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

`impl Hash for SocketAddr`[src]

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

`impl Hash for OsString`[src]

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

`impl Hash for SystemTime`[src]

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

`impl Hash for ThreadId`[src]

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

`impl Hash for CString`[src]

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

`impl Hash for !`[src]

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

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

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

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

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

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

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

`impl Hash for char`[src]

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

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

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

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

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

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

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

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

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

`impl Hash for Duration`[src]

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

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

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

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

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

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

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

`impl Hash for NonZeroU32`[src]

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

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