Struct tantivy_stacker::ArenaHashMap

pub struct ArenaHashMap {
    pub memory_arena: MemoryArena,
    /* private fields */
}

Customized HashMap with &[u8] keys

Its main particularity is that rather than storing its keys in the heap, keys are stored in a memory arena inline with the values.

The quirky API has the benefit of avoiding the computation of the hash of the key twice, or copying the key as long as there is no insert.

ArenaHashMap is like SharedArenaHashMap but takes ownership of the memory arena. The memory arena stores the serialized keys and values.

Fields

memory_arena: MemoryArena

Implementations

impl ArenaHashMap

pub fn with_capacity(table_size: usize) -> ArenaHashMap

pub fn read<Item: Copy + 'static>(&self, addr: Addr) -> Item

pub fn mem_usage(&self) -> usize

pub fn is_empty(&self) -> bool

pub fn len(&self) -> usize

pub fn iter(&self) -> impl Iterator<Item = (&[u8], Addr)>

pub fn get<V>(&self, key: &[u8]) -> Option<V>

where V: Copy + 'static,

Get a value associated to a key.

pub fn mutate_or_create<V>( &mut self, key: &[u8], updater: impl FnMut(Option<V>) -> V )

where V: Copy + 'static,

update create a new entry for a given key if it does not exist or updates the existing entry.

The actual logic for this update is define in the updater argument.

If the key is not present, updater will receive None and will be in charge of returning a default value. If the key already as an associated value, then it will be passed Some(previous_value).

Trait Implementations

impl Default for ArenaHashMap

fn default() -> Self

Returns the “default value” for a type.