Struct SecondaryMap

pub struct SecondaryMap<K, V>
where
    K: EntityRef,
    V: Clone,
{ /* private fields */ }

A mapping K -> V for densely indexed entity references.

The SecondaryMap data structure uses the dense index space to implement a map with a vector. Unlike PrimaryMap, an SecondaryMap can’t be used to allocate entity references. It is used to associate secondary information with entities.

The map does not track if an entry for a key has been inserted or not. Instead it behaves as if all keys have a default entry from the beginning.

Implementations

impl<K, V> SecondaryMap<K, V>

where K: EntityRef, V: Clone,

Shared SecondaryMap implementation for all value types.

pub fn new() -> Self

where V: Default,

Create a new empty map.

pub fn with_capacity(capacity: usize) -> Self

where V: Default,

Create a new, empty map with the specified capacity.

The map will be able to hold exactly capacity elements without reallocating.

pub fn with_default(default: V) -> Self

Create a new empty map with a specified default value.

This constructor does not require V to implement Default.

pub fn capacity(&self) -> usize

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

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

Get the element at k if it exists.

pub fn is_empty(&self) -> bool

Is this map completely empty?

pub fn clear(&mut self)

Remove all entries from this map.

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

Iterate over all the keys and values in this map.

pub fn iter_mut(&mut self) -> IterMut<'_, K, V>

Iterate over all the keys and values in this map, mutable edition.

pub fn keys(&self) -> Keys<K>

Iterate over all the keys in this map.

pub fn values(&self) -> Iter<'_, V>

Iterate over all the values in this map.

pub fn values_mut(&mut self) -> IterMut<'_, V>

Iterate over all the values in this map, mutable edition.

pub fn resize(&mut self, n: usize)

Resize the map to have n entries by adding default entries as needed.

Trait Implementations

impl<K, V> Clone for SecondaryMap<K, V>

where K: EntityRef + Clone, V: Clone + Clone,

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

where K: EntityRef + Debug, V: Clone + Debug,

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

Formats the value using the given formatter.

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

where K: EntityRef, V: Clone + Default,

fn default() -> SecondaryMap<K, V>

Returns the “default value” for a type.

impl<K, V> Hash for SecondaryMap<K, V>

where K: EntityRef + Hash, V: Clone + Hash,

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<K, V> Index<K> for SecondaryMap<K, V>

where K: EntityRef, V: Clone,

Immutable indexing into an SecondaryMap.

All keys are permitted. Untouched entries have the default value.

type Output = V

The returned type after indexing.

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

Performs the indexing (container[index]) operation.

impl<K, V> IndexMut<K> for SecondaryMap<K, V>

where K: EntityRef, V: Clone,

Mutable indexing into an SecondaryMap.

The map grows as needed to accommodate new keys.

fn index_mut(&mut self, k: K) -> &mut V

Performs the mutable indexing (container[index]) operation.

impl<K, V> PartialEq for SecondaryMap<K, V>

where K: EntityRef, V: Clone + PartialEq,

fn eq(&self, other: &Self) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<K, V> Eq for SecondaryMap<K, V>

where K: EntityRef, V: Clone + PartialEq + Eq,