#hasher #hash #hashing #seed #function

fasthash-fork

A suite of non-cryptographic hash functions for Rust - Forked to release current code-base

1 unstable release

0.4.1 Mar 10, 2022

#61 in #seed


Used in 3 crates (2 directly)

Apache-2.0

150KB
2.5K SLoC

A suite of non-cryptographic hash functions for Rust.

Example

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

use fasthash::{metro, MetroHasher};

fn hash<T: Hash>(t: &T) -> u64 {
    let mut s: MetroHasher = Default::default();
    t.hash(&mut s);
    s.finish()
}

let h = metro::hash64(b"hello world\xff");

assert_eq!(h, hash(&"hello world"));

By default, HashMap uses a hashing algorithm selected to provide resistance against HashDoS attacks. The hashing algorithm can be replaced on a per-HashMap basis using the HashMap::with_hasher or HashMap::with_capacity_and_hasher methods.

It also cowork with HashMap or HashSet, act as a hash function

use std::collections::HashSet;

use fasthash::spooky::Hash128;

let mut set = HashSet::with_hasher(Hash128);
set.insert(2);

Or use RandomState<CityHash64> with a random seed.

use std::collections::HashMap;

use fasthash::{city, RandomState};

let s = RandomState::<city::Hash64>::new();
let mut map = HashMap::with_hasher(s);

assert_eq!(map.insert(37, "a"), None);
assert_eq!(map.is_empty(), false);

map.insert(37, "b");
assert_eq!(map.insert(37, "c"), Some("b"));
assert_eq!(map[&37], "c");

Dependencies

~7MB
~96K SLoC