bevy/crates/bevy_utils/src/lib.rs

pub use ahash::AHasher;
use ahash::RandomState;
pub use instant::{Duration, Instant};
use std::{future::Future, pin::Pin};
pub use tracing;
pub use uuid::Uuid;

#[cfg(not(target_arch = "wasm32"))]
pub type BoxedFuture<'a, T> = Pin<Box<dyn Future<Output = T> + Send + 'a>>;

#[cfg(target_arch = "wasm32")]
pub type BoxedFuture<'a, T> = Pin<Box<dyn Future<Output = T> + 'a>>;

/// A hasher builder that will create a fixed hasher.
#[derive(Default)]
pub struct FixedState;

impl std::hash::BuildHasher for FixedState {
    type Hasher = AHasher;

    #[inline]
    fn build_hasher(&self) -> AHasher {
        AHasher::new_with_keys(
            0b1001010111101110000001001100010000000011001001101011001001111000,
            0b1100111101101011011110001011010100000100001111100011010011010101,
        )
    }
}

/// A std hash map implementing AHash, a high speed keyed hashing algorithm
/// intended for use in in-memory hashmaps.
///
/// AHash is designed for performance and is NOT cryptographically secure.
pub type HashMap<K, V> = std::collections::HashMap<K, V, RandomState>;

/// A stable std hash map implementing AHash, a high speed keyed hashing algorithm
/// intended for use in in-memory hashmaps.
///
/// Unlike [`HashMap`] this has an iteration order that only depends on the order
/// of insertions and deletions and not a random source.
///
/// AHash is designed for performance and is NOT cryptographically secure.
pub type StableHashMap<K, V> = std::collections::HashMap<K, V, FixedState>;

/// A std hash set implementing AHash, a high speed keyed hashing algorithm
/// intended for use in in-memory hashmaps.
///
/// AHash is designed for performance and is NOT cryptographically secure.
pub type HashSet<K> = std::collections::HashSet<K, RandomState>;

/// A stable std hash set implementing AHash, a high speed keyed hashing algorithm
/// intended for use in in-memory hashmaps.
///
/// Unlike [`HashSet`] this has an iteration order that only depends on the order
/// of insertions and deletions and not a random source.
///
/// AHash is designed for performance and is NOT cryptographically secure.
pub type StableHashSet<K> = std::collections::HashSet<K, FixedState>;