tag | 9a11c997a94d21fa29f57095a0dc0d14d3c6cf6d | |
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tagger | The Android Open Source Project <initial-contribution@android.com> | Thu Nov 10 21:09:01 2022 -0800 |
object | 4c66b21025a8d06fd01d8683ac3ae8c9f3990833 |
aml_tz3_312410020
commit | 4c66b21025a8d06fd01d8683ac3ae8c9f3990833 | [log] [tgz] |
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author | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Wed Jun 15 21:44:14 2022 +0000 |
committer | Android Build Coastguard Worker <android-build-coastguard-worker@google.com> | Wed Jun 15 21:44:14 2022 +0000 |
tree | 69609eba0194af44d59844c6df753b5c412889ee | |
parent | c5210d68ecc517bf5f5098c36d54a3b19d8a5818 [diff] | |
parent | 0249166812f2b30a4b7e29165f25c83932755809 [diff] |
Snap for 8730993 from 0249166812f2b30a4b7e29165f25c83932755809 to mainline-tzdata3-release Change-Id: I94f9214ba4f13716083e6c8c0083e096600816b2
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.