Struct CidHashMap 

pub struct CidHashMap<V> {
    compact: HashMap<CidV1DagCborBlake2b256, V>,
    uncompact: HashMap<Uncompactable, V>,
}

A space-optimised hash map of Cids, matching the API for std::collections::HashMap.

We accept the implementation complexity of per-compaction-method HashMaps for the space savings, which are constant per-variant, rather than constant per-item.

This is dramatic for large maps! Using, e.g SmallCidNonEmptyVec will cost 25% more per-CID in the median case (32 B vs 40 B)

Fields

compact: HashMap<CidV1DagCborBlake2b256, V>

uncompact: HashMap<Uncompactable, V>

Implementations

impl<V> CidHashMap<V>

pub fn new() -> Self

Creates an empty HashMap.

See also HashMap::new.

pub fn len(&self) -> usize

Returns the number of elements in the map.

See also HashMap::len.

pub fn capacity_min(&self) -> usize

How many values this map is guaranteed to hold without reallocating.

pub fn total_capacity(&self) -> usize

Reflective of reserved capacity of this map.

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

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

See also HashMap::contains_key.

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

Returns a reference to the value corresponding to the key.

See also HashMap::get.

pub fn insert(&mut self, key: Cid, 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.

See also HashMap::insert.

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

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

See also HashMap::remove.

pub fn is_empty(&self) -> bool

Returns true if the map is empty.

See also HashMap::is_empty.

impl<V> CidHashMap<V>

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

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

See also HashMap::entry.

Trait Implementations

impl<V: Clone> Clone for CidHashMap<V>

fn clone(&self) -> CidHashMap<V>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<V: Debug> Debug for CidHashMap<V>

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

Formats the value using the given formatter.

impl<V> Default for CidHashMap<V>

fn default() -> Self

Returns the “default value” for a type.

impl<V> Extend<(Cid<64>, V)> for CidHashMap<V>

fn extend<T: IntoIterator<Item = (Cid, V)>>(&mut self, iter: T)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬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<V> FromIterator<(Cid<64>, V)> for CidHashMap<V>

fn from_iter<T: IntoIterator<Item = (Cid, V)>>(iter: T) -> Self

Creates a value from an iterator.

impl<V> IntoIterator for CidHashMap<V>

type Item = (Cid<64>, V)

The type of the elements being iterated over.

type IntoIter = IntoIter<V>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<V: PartialEq> PartialEq for CidHashMap<V>

fn eq(&self, other: &CidHashMap<V>) -> 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<V: Eq> Eq for CidHashMap<V>

impl<V> StructuralPartialEq for CidHashMap<V>