| commit | 96271d2dd8e2ced0aa6f2661c713423fc89b7010 | [log] [tgz] |
|---|---|---|
| author | Android Build Coastguard Worker <[email protected]> | Fri Jul 07 01:03:12 2023 +0000 |
| committer | Android Build Coastguard Worker <[email protected]> | Fri Jul 07 01:03:12 2023 +0000 |
| tree | 6a58b521516f9270099a4bb3a83d40401f935e16 | |
| parent | eca7b3fafd51f771974bfa3c4ff87574f5ae5545 [diff] | |
| parent | 3fac601af78ca04f3f0829861ae23fc5681d0b41 [diff] |
Snap for 10447354 from 3fac601af78ca04f3f0829861ae23fc5681d0b41 to mainline-resolv-release Change-Id: I93d98f095379132b21c774c7f45efd0a647dd2c9
This crate is a fork of linked-hash-map that builds on top of hashbrown to implement more up to date versions of LinkedHashMap LinkedHashSet, and LruCache.
One important API change is that when a LinkedHashMap is used as a LRU cache, it allows you to easily retrieve an entry and move it to the back OR produce a new entry at the back without needlessly repeating key hashing and lookups:
let mut lru_cache = LinkedHashMap::new(); let key = "key".to_owned(); // Try to find my expensive to construct and hash key let _cached_val = match lru_cache.raw_entry_mut().from_key(&key) { RawEntryMut::Occupied(mut occupied) => { // Cache hit, move entry to the back. occupied.to_back(); occupied.into_mut() } RawEntryMut::Vacant(vacant) => { // Insert expensive to construct key and expensive to compute value, // automatically inserted at the back. vacant.insert(key.clone(), 42).1 } };
Or, a simpler way to do the same thing:
let mut lru_cache = LinkedHashMap::new(); let key = "key".to_owned(); let _cached_val = lru_cache .raw_entry_mut() .from_key(&key) .or_insert_with(|| (key.clone(), 42));
This crate contains a decent amount of unsafe code from handling its internal linked list, and the unsafe code has diverged quite a lot from the original linked-hash-map implementation. It currently passes tests under miri and sanitizers, but it should probably still receive more review and testing, and check for test code coverage.
There is a huge amount of code in this crate that is copied verbatim from linked-hash-map and hashbrown, especially tests, associated types like iterators, and things like Debug impls.
This library is licensed the same as linked-hash-map and hashbrown, it is licensed under either of:
at your option.