Enum rustc_data_structures::sso::SsoHashMap

pub enum SsoHashMap<K, V> {
    Array(ArrayVec<(K, V), SSO_ARRAY_SIZE>),
    Map(FxHashMap<K, V>),
}

Small-storage-optimized implementation of a map.

Stores elements in a small array up to a certain length and switches to HashMap when that length is exceeded.

Variants

Array(ArrayVec<(K, V), SSO_ARRAY_SIZE>)

Map(FxHashMap<K, V>)

Implementations

impl<K, V> SsoHashMap<K, V>

pub fn new() -> Self

Creates an empty SsoHashMap.

pub fn with_capacity(cap: usize) -> Self

Creates an empty SsoHashMap with the specified capacity.

pub fn clear(&mut self)

Clears the map, removing all key-value pairs. Keeps the allocated memory for reuse.

pub fn capacity(&self) -> usize

Returns the number of elements the map can hold without reallocating.

pub fn len(&self) -> usize

Returns the number of elements in the map.

pub fn is_empty(&self) -> bool

Returns true if the map contains no elements.

pub fn iter(
    &self
) -> EitherIter<Map<Iter<'_, (K, V)>, fn(&(K, V)) -> (&K, &V)>, Iter<'_, K, V>>

An iterator visiting all key-value pairs in arbitrary order. The iterator element type is (&'a K, &'a V).

pub fn iter_mut(&mut self) -> impl Iterator<Item = (&K, &mut V)>

An iterator visiting all key-value pairs in arbitrary order, with mutable references to the values. The iterator element type is (&'a K, &'a mut V).

pub fn keys(&self) -> impl Iterator<Item = &K>

An iterator visiting all keys in arbitrary order. The iterator element type is &'a K.

pub fn values(&self) -> impl Iterator<Item = &V>

An iterator visiting all values in arbitrary order. The iterator element type is &'a V.

pub fn values_mut(&mut self) -> impl Iterator<Item = &mut V>

An iterator visiting all values mutably in arbitrary order. The iterator element type is &'a mut V.

pub fn drain(&mut self) -> impl Iterator<Item = (K, V)> + '_

Clears the map, returning all key-value pairs as an iterator. Keeps the allocated memory for reuse.

impl<K: Eq + Hash, V> SsoHashMap<K, V>

fn migrate_if_full(&mut self)

Changes underlying storage from array to hashmap if array is full.

pub fn reserve(&mut self, additional: usize)

Reserves capacity for at least additional more elements to be inserted in the SsoHashMap. The collection may reserve more space to avoid frequent reallocations.

pub fn shrink_to_fit(&mut self)

Shrinks the capacity of the map as much as possible. It will drop down as much as possible while maintaining the internal rules and possibly leaving some space in accordance with the resize policy.

pub fn retain<F>(&mut self, f: F)where
    F: FnMut(&K, &mut V) -> bool,

Retains only the elements specified by the predicate.

pub fn insert(&mut self, key: K, value: V) -> Option<V>

Inserts a key-value pair into the map.

If the map did not have this key present, None is returned.

If the map did have this key present, the value is updated, and the old value is returned. The key is not updated, though; this matters for types that can be == without being identical. See the [module-level documentation] for more.

pub fn remove(&mut self, key: &K) -> Option<V>

Removes a key from the map, returning the value at the key if the key was previously in the map.

pub fn remove_entry(&mut self, key: &K) -> Option<(K, V)>

Removes a key from the map, returning the stored key and value if the key was previously in the map.

pub fn get(&self, key: &K) -> Option<&V>

Returns a reference to the value corresponding to the key.

pub fn get_mut(&mut self, key: &K) -> Option<&mut V>

Returns a mutable reference to the value corresponding to the key.

pub fn get_key_value(&self, key: &K) -> Option<(&K, &V)>

Returns the key-value pair corresponding to the supplied key.

pub fn contains_key(&self, key: &K) -> bool

Returns true if the map contains a value for the specified key.

pub fn entry(&mut self, key: K) -> Entry<'_, K, V>

Gets the given key’s corresponding entry in the map for in-place manipulation.

Trait Implementations

impl<K: Clone, V: Clone> Clone for SsoHashMap<K, V>

fn clone(&self) -> SsoHashMap<K, V>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<K, V> Debug for SsoHashMap<K, V>where
    K: Debug,
    V: Debug,

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<K, V> Default for SsoHashMap<K, V>

fn default() -> Self

Returns the “default value” for a type.

impl<'a, K, V> Extend<(&'a K, &'a V)> for SsoHashMap<K, V>where
    K: Eq + Hash + Copy,
    V: Copy,

fn extend<T: IntoIterator<Item = (&'a K, &'a V)>>(&mut self, iter: T)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, (k, v): (&'a K, &'a V))

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<K: Eq + Hash, V> Extend<(K, V)> for SsoHashMap<K, V>

fn extend<I>(&mut self, iter: I)where
    I: IntoIterator<Item = (K, V)>,

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, (k, v): (K, V))

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<K: Eq + Hash, V> FromIterator<(K, V)> for SsoHashMap<K, V>

fn from_iter<I: IntoIterator<Item = (K, V)>>(iter: I) -> SsoHashMap<K, V>

Creates a value from an iterator.

impl<'a, K, V> Index<&'a K> for SsoHashMap<K, V>where
    K: Eq + Hash,

type Output = V

The returned type after indexing.

fn index(&self, key: &K) -> &V

Performs the indexing (container[index]) operation.

impl<'a, K, V> IntoIterator for &'a SsoHashMap<K, V>

type IntoIter = EitherIter<Map<Iter<'a, (K, V)>, fn(&'a (K, V)) -> (&'a K, &'a V)>, Iter<'a, K, V>>

Which kind of iterator are we turning this into?

type Item = (&'a K, &'a V)

The type of the elements being iterated over.

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<'a, K, V> IntoIterator for &'a mut SsoHashMap<K, V>

type IntoIter = EitherIter<Map<IterMut<'a, (K, V)>, fn(&'a mut (K, V)) -> (&'a K, &'a mut V)>, IterMut<'a, K, V>>

Which kind of iterator are we turning this into?

type Item = (&'a K, &'a mut V)

The type of the elements being iterated over.

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<K, V> IntoIterator for SsoHashMap<K, V>

type IntoIter = EitherIter<IntoIter<(K, V), 8>, IntoIter<K, V>>

Which kind of iterator are we turning this into?

type Item = (K, V)

The type of the elements being iterated over.

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

Layout

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.