# axhash-core
`axhash-core` is the low-level Rust engine behind the AxHash family.
Most Rust users should prefer the top-level `axhash` crate because it provides a simpler import path. Use `axhash-core` when you want direct access to the core engine, need `no_std`, or are building your own bindings.
## Installation
```toml
[dependencies]
axhash-core = "0.8"
```
## Features
- `no_std` compatible
- zero allocation on the main hashing path
- deterministic hashing with optional seeds
- streaming hasher implementation
- `HashMap` integration through `AxBuildHasher`
- runtime backend detection
## Examples
Hash bytes with the default seed:
```rust
use axhash_core::axhash;
fn main() {
let digest = axhash(b"hello axhash");
println!("{digest:016x}");
}
```
Hash bytes with a custom seed:
```rust
use axhash_core::axhash_seeded;
fn main() {
let digest = axhash_seeded(b"hello axhash", 0x1234_5678);
println!("{digest:016x}");
}
```
Hash any value that implements `Hash`:
```rust
use axhash_core::axhash_of_seeded;
#[derive(Hash)]
struct SessionKey {
account_id: u64,
region_id: u32,
flags: u32,
}
fn main() {
let key = SessionKey {
account_id: 42,
region_id: 7,
flags: 3,
};
let digest = axhash_of_seeded(&key, 0xdead_beef);
println!("{digest:016x}");
}
```
Use the streaming hasher:
```rust
use axhash_core::AxHasher;
use std::hash::Hasher as _;
fn main() {
let mut hasher = AxHasher::new_with_seed(0x1234);
hasher.write(b"part-1");
hasher.write(b"part-2");
println!("{:016x}", hasher.finish());
}
```
Use AxHash in `HashMap`:
```rust
use axhash_core::AxBuildHasher;
use std::collections::HashMap;
fn main() {
let mut map: HashMap<&str, i32, AxBuildHasher> =
HashMap::with_hasher(AxBuildHasher::with_seed(0xfeed_beef));
map.insert("alpha", 1);
map.insert("beta", 2);
println!("{:?}", map.get("alpha"));
}
```
Check the active backend:
```rust
use axhash_core::{runtime_backend, runtime_has_aes};
fn main() {
println!("{:?}", runtime_backend());
println!("{}", runtime_has_aes());
}
```
## License
MIT.