A Rust implementation of the xxHash algorithm.

Examples

These examples use XxHash64 but the same ideas can be used for XxHash32 or XxHash3_64.

Hashing arbitrary data

When all the data is available at once

use twox_hash::XxHash64;

let seed = 1234;
let hash = XxHash64::oneshot(seed, b"some bytes");
assert_eq!(0xeab5_5659_a496_d78b, hash);

When the data is streaming

use std::hash::Hasher as _;
use twox_hash::XxHash64;

let seed = 1234;
let mut hasher = XxHash64::with_seed(seed);
hasher.write(b"some");
hasher.write(b" ");
hasher.write(b"bytes");
let hash = hasher.finish();
assert_eq!(0xeab5_5659_a496_d78b, hash);

In a HashMap

With a default seed

use std::{collections::HashMap, hash::BuildHasherDefault};
use twox_hash::XxHash64;

let mut hash = HashMap::<_, _, BuildHasherDefault<XxHash64>>::default();
hash.insert(42, "the answer");
assert_eq!(hash.get(&42), Some(&"the answer"));

With a random seed

use std::collections::HashMap;
use twox_hash::xxhash64;

let mut hash = HashMap::<_, _, xxhash64::RandomState>::default();
hash.insert(42, "the answer");
assert_eq!(hash.get(&42), Some(&"the answer"));

With a fixed seed

use std::collections::HashMap;
use twox_hash::xxhash64;

let mut hash = HashMap::with_hasher(xxhash64::State::with_seed(0xdead_cafe));
hash.insert(42, "the answer");
assert_eq!(hash.get(&42), Some(&"the answer"));

Feature Flags

Benchmarks

See benchmarks in the comparison README.

Contributing

1. Fork it (https://github.com/shepmaster/twox-hash/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Add a failing test.
4. Add code to pass the test.
5. Commit your changes (git commit -am 'Add some feature')
6. Ensure tests pass.
7. Push to the branch (git push origin my-new-feature)
8. Create a new Pull Request