Struct budvm::budmap::BudMap

pub struct BudMap<Key, Value, HashBuilder = RandomState> { /* private fields */ }

A std::collections::HashMap alternative that provides some guarantees on entry order.

This implementation preserves insert order until an operation that removes a key occurs. To keep this implementation efficient, when a removal occurs, the order is updated by moving the last key inserted to replace the entry being removed.

The benefit of keeping the order is that an iterator can be made against this collection that doesn’t require borrowing the original value. Additionally, methods can be used to retrieve entries by index instead of just by key.

Implementations

impl<Key, Value> BudMap<Key, Value, RandomState>where Key: Eq + Hash + Debug,

pub fn with_capacity(minimum_capacity: usize) -> Self

Returns an empty map with enough room for minimum_capacity elements to be inserted without allocations (assuming no hash collisions).

impl<Key, Value, HashBuilder> BudMap<Key, Value, HashBuilder>where Key: Eq + Hash + Debug, HashBuilder: BuildHasher,

pub fn with_capacity_and_hasher( minimum_capacity: usize, hash_builder: HashBuilder ) -> Self

Returns an empty map with enough room for minimum_capacity elements to be inserted without allocations (assuming no hash collisions). Keys are hashed using hash_builder.

pub const fn with_hasher(hash_builder: HashBuilder) -> Self

Returns an empty map whose keys are hashed using hash_builder.

pub fn entry(&mut self, key: Key) -> Entry<'_, Key, Value, HashBuilder>

Looks up an entry for key. If one is found, Entry::Occupied will be returned. If one is not found, Entry::Vacant will be returned.

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

Inserts the key-value pair into the map. If an existing value was stored for the given key, it will be returned.

pub fn remove(&mut self, key: &Key) -> Option<Value>

Removes a key from the map. If the key was found, the value stored will be returned.

pub fn len(&self) -> usize

Returns the number of entries contained in this map.

pub fn is_empty(&self) -> bool

Returns true if no entries are contained in this map.

pub fn get(&self, key: &Key) -> Option<&Value>

Returns a value for a given key.

pub fn get_by_index(&self, index: usize) -> Option<&Value>

Returns a value for a given 0-based index.

pub fn iter(&self) -> Iter<'_, Key, Value>

Returns an interator for this map.

Trait Implementations

impl<Key: Clone, Value: Clone, HashBuilder: Clone> Clone for BudMap<Key, Value, HashBuilder>

fn clone(&self) -> BudMap<Key, Value, HashBuilder>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<Key: Debug, Value: Debug, HashBuilder: Debug> Debug for BudMap<Key, Value, HashBuilder>

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

Formats the value using the given formatter.

impl<Key, Value> Default for BudMap<Key, Value, RandomState>

fn default() -> Self

Returns the “default value” for a type.