Trait QueryCache

pub trait QueryCache: Sized {
    type Key: Hash + Eq + Copy + Debug;
    type Value: Copy;

    // Required methods
    fn lookup(&self, key: &Self::Key) -> Option<(Self::Value, DepNodeIndex)>;
    fn complete(&self, key: Self::Key, value: Self::Value, index: DepNodeIndex);
    fn iter(&self, f: &mut dyn FnMut(&Self::Key, &Self::Value, DepNodeIndex));
}

Trait for types that serve as an in-memory cache for query results, for a given key (argument) type and value (return) type.

Types implementing this trait are associated with actual key/value types by the Cache associated type of the rustc_middle::query::Key trait.

Required Associated Types

type Key: Hash + Eq + Copy + Debug

type Value: Copy

Required Methods

fn lookup(&self, key: &Self::Key) -> Option<(Self::Value, DepNodeIndex)>

Returns the cached value (and other information) associated with the given key, if it is present in the cache.

fn complete(&self, key: Self::Key, value: Self::Value, index: DepNodeIndex)

Adds a key/value entry to this cache.

Called by some part of the query system, after having obtained the value by executing the query or loading a cached value from disk.

fn iter(&self, f: &mut dyn FnMut(&Self::Key, &Self::Value, DepNodeIndex))

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<K, V> QueryCache for DefaultCache<K, V>

where K: Eq + Hash + Copy + Debug, V: Copy,

type Key = K

type Value = V

impl<K, V> QueryCache for VecCache<K, V, DepNodeIndex>

where K: Idx + Eq + Hash + Copy + Debug, V: Copy,

type Key = K

type Value = V

impl<V> QueryCache for DefIdCache<V>

where V: Copy,

type Key = DefId

type Value = V

impl<V> QueryCache for SingleCache<V>

where V: Copy,

type Key = ()

type Value = V