openethereum/util/fastmap/src/lib.rs
David e2095d4a5d Move ethereum-specific H256FastMap type to own crate (#9307)
* Add a `fastmap` crate that provides the H256FastMap specialized HashMap

* Use `fastmap` instead of `plain_hasher`

* Update submodules for Reasons™

* Submodule update
2018-08-09 09:51:48 +02:00

39 lines
1.3 KiB
Rust

// Copyright 2015-2018 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
//! Provides a `H256FastMap` type with H256 keys and fast hashing function.
extern crate ethereum_types;
extern crate plain_hasher;
use ethereum_types::H256;
use std::hash;
use std::collections::HashMap;
use plain_hasher::PlainHasher;
/// Specialized version of `HashMap` with H256 keys and fast hashing function.
pub type H256FastMap<T> = HashMap<H256, T, hash::BuildHasherDefault<PlainHasher>>;
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_works() {
let mut h = H256FastMap::default();
h.insert(H256::from(123), "abc");
}
}