Struct SparseSecondaryEntityMap

pub struct SparseSecondaryEntityMap<V, S: BuildHasher = RandomState> { /* private fields */ }

Sparse secondary map for associating data with previously stored entities in a generational arena.

Implementations

impl<V> SparseSecondaryEntityMap<V, RandomState>

pub fn new() -> Self

Constructs a new, empty SparseSecondaryEntityMap.

pub fn with_capacity(capacity: usize) -> Self

Creates an empty SparseSecondaryEntityMap with the given capacity of slots.

The secondary map will not reallocate until it holds at least capacity slots.

impl<V, S: BuildHasher> SparseSecondaryEntityMap<V, S>

pub fn with_hasher(hash_builder: S) -> Self

Creates an empty SparseSecondaryEntityMap which will use the given hash builder to hash keys.

The secondary map will not reallocate until it holds at least capacity slots.

pub fn with_capacity_and_hasher(capacity: usize, hash_builder: S) -> Self

Creates an empty SparseSecondaryEntityMap with the given capacity of slots, using hash_builder to hash the keys.

The secondary map will not reallocate until it holds at least capacity slots.

pub fn len(&self) -> usize

Returns the number of elements in the secondary map.

pub fn is_empty(&self) -> bool

Returns if the secondary map is empty.

pub fn capacity(&self) -> usize

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

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

Reserves capacity for at least additional more slots in the SparseSecondaryEntityMap. The collection may reserve more space to avoid frequent reallocations.

Panics

Panics if the new allocation size overflows usize.

pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError>

Tries to reserve capacity for at least additional more slots in the SparseSecondaryEntityMap. The collection may reserve more space to avoid frequent reallocations.

pub fn contains(&self, entity: Entity) -> bool

Returns true if the secondary map contains the given entity.

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

Inserts a value into the secondary map at the given entity.

Returns None if this entity was not present in the map, and the old value otherwise.

pub fn remove(&mut self, entity: Entity) -> Option<V>

Removes a entity from the secondary map, returning the value at the entity if the entity was not previously removed.

pub fn clear(&mut self)

Clears the secondary map. Keeps the allocated memory for reuse.

pub fn get(&self, entity: Entity) -> Option<&V>

Returns a reference to the value corresponding to the entity.

pub unsafe fn get_unchecked(&self, entity: Entity) -> &V

Returns a reference to the value corresponding to the entity without version or bounds checking.

Safety

This should only be used if contains(entity) is true. Otherwise it is potentially unsafe.

pub fn get_mut(&mut self, entity: Entity) -> Option<&mut V>

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

pub unsafe fn get_unchecked_mut(&mut self, entity: Entity) -> &mut V

Returns a mutable reference to the value corresponding to the entity without version or bounds checking.

Safety

This should only be used if contains(entity) is true. Otherwise it is potentially unsafe.

pub fn get_or_insert_with<F>(&mut self, entity: Entity, f: F) -> V

where F: FnOnce() -> V, V: Clone + Copy,

Returns the value corresponding to the entity if it exists, otherwise inserts the value returned by f and returns it.

pub fn get_disjoint_mut<const N: usize>( &mut self, entities: [Entity; N], ) -> Option<[&mut V; N]>

Returns mutable references to the values corresponding to the given keys. All keys must be valid and disjoint, otherwise None is returned.

pub unsafe fn get_disjoint_unchecked_mut<const N: usize>( &mut self, entities: [Entity; N], ) -> [&mut V; N]

Returns mutable references to the values corresponding to the given keys. All keys must be valid and disjoint.

Safety

This should only be used if contains(entity) is true for every given entity and no two keys are equal. Otherwise it is potentially unsafe.

Trait Implementations

impl<V: Clone, S: Clone + BuildHasher> Clone for SparseSecondaryEntityMap<V, S>

fn clone(&self) -> SparseSecondaryEntityMap<V, S>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<V: Debug, S: Debug + BuildHasher> Debug for SparseSecondaryEntityMap<V, S>

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

Formats the value using the given formatter.

impl<V, S> Default for SparseSecondaryEntityMap<V, S>

where S: BuildHasher + Default,

fn default() -> Self

Returns the “default value” for a type.