[][src]Struct dyn_cache::local::LocalCache

pub struct LocalCache { /* fields omitted */ }

Holds arbitrary query results which are namespaced by arbitrary scope types. Usually used through SharedLocalCache::cache_with and SharedLocalCache::gc.

Query types

Note: the types referenced in this documentation are only visible on individual methods, as LocalCache is not itself a generic type.

Storage is sharded by the type of the query. The type of a query has three parts:

The query scope is the value which indexes the storage for a particular query type, it has the bound Scope: 'static + Eq + Hash.

Each Scope corresponds to at most a single Input: 'static and a single Output: 'static value at any given time.

Reading stored values

See LocalCache::get which accepts borrowed forms of Scope and Input: Key and Arg respectively. Arg must satisfy PartialEq<Input> to determine whether to return a stored output.

Garbage Collection

Each time LocalCache::gc is called it removes any values which haven't been referenced since the prior call.

After each GC, all values still in the cache are marked garbage. They are marked live again when inserted with LocalCache::store or read with LocalCache::get.


impl LocalCache[src]

pub fn get<'k, Key: ?Sized, Scope, Arg: ?Sized, Input, Output>(
    key: &'k Key,
    arg: &Arg
) -> Result<&Output, CacheMiss<'k, Key, Scope, Input, Output>> where
    Key: Eq + Hash + ToOwned<Owned = Scope>,
    Scope: 'static + Borrow<Key> + Eq + Hash,
    Arg: PartialEq<Input> + ToOwned<Owned = Input>,
    Input: 'static + Borrow<Arg>,
    Output: 'static, 

Return a reference to a query's stored output if a result is stored and arg equals the previously-stored Input. If a reference is returned, the stored input/output is marked as a root and will not be GC'd the next call.

If no reference is found, a CacheMiss is returned. Call CacheMiss::init to get a CacheEntry to pass to LocalCache::store.

pub fn store<Key: ?Sized, Scope, Input, Output>(
    &mut self,
    entry: CacheEntry<Key, Scope, Input, Output>
) where
    Key: Eq + Hash + ToOwned<Owned = Scope>,
    Scope: 'static + Borrow<Key> + Eq + Hash,
    Input: 'static,
    Output: 'static, 

Stores a fresh CacheEntry whose input/output will not be GC'd at the next call. Call LocalCache::get to get a CacheMiss and CacheMiss::init to get a CacheEntry.

pub fn gc(&mut self)[src]

Drop any values which have not been marked alive since the last call to this method.

Trait Implementations

impl Debug for LocalCache[src]

impl Default for LocalCache[src]

impl From<LocalCache> for SharedLocalCache[src]

impl RefUnwindSafe for LocalCache[src]

impl UnwindSafe for LocalCache[src]

Auto Trait Implementations

impl !Send for LocalCache

impl !Sync for LocalCache

impl Unpin for LocalCache

Blanket Implementations

impl<T> Any for T where
    T: 'static + ?Sized

impl<T> AsContext for T where
    T: Debug + 'static, 

impl<T> Borrow<T> for T where
    T: ?Sized

impl<T> BorrowMut<T> for T where
    T: ?Sized

impl<T> Downcast for T where
    T: Any

impl<T> Erased for T

impl<T> From<T> for T[src]

impl<T, U> Into<U> for T where
    U: From<T>, 

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.