//! Customized HashMap and Hasher implementation optimized for using `ObjectId`s as keys.//!//! The crate mirrors `std::collections` in layout for familiarity.#![deny(missing_docs, rust_2018_idioms)]#![forbid(unsafe_code)] use git_hash::ObjectId;pub use hashbrown::{hash_map, hash_set, raw, Equivalent}; ///pub mod hash {    /// A Hasher for usage with HashMap keys that are already robust hashes (like an `ObjectId`).    /// The first `8` bytes of the hash are used as the `HashMap` hash    #[derive(Default, Clone, Copy)]    pub struct Hasher(u64);     impl std::hash::Hasher for Hasher {        fn finish(&self) -> u64 {            self.0        }         #[inline(always)]        fn write(&mut self, bytes: &[u8]) {            self.0 = u64::from_ne_bytes(bytes[..8].try_into().unwrap());        }    }     /// A Hasher for usage with HashMap keys that are already robust hashes (like an `ObjectId`).    /// The first `8` bytes of the hash are used as the `HashMap` hash    #[derive(Default, Clone, Copy)]    pub struct Builder;    impl std::hash::BuildHasher for Builder {        type Hasher = Hasher;         fn build_hasher(&self) -> Self::Hasher {            Hasher::default()        }    }} /// A HashMap for usage with keys that are already robust hashes (like an `ObjectId`)./// The first `8` bytes of the hash are used as the `HashMap` hashpub type HashMap<K, V> = hashbrown::HashMap<K, V, hash::Builder>;/// A HashSet for usage with keys that are already robust hashes (like an `ObjectId`)./// The first `8` bytes of the hash are used as the `HashMap` hashpub type HashSet<T = ObjectId> = hashbrown::HashSet<T, hash::Builder>;