SsoHashSet/SsoHashMap API greatly expanded
Now both provide almost complete API of their non-SSO counterparts.
This commit is contained in:
Valerii Lashmanov
parent
5c224a484d
commit
0600b178aa
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@ -1,32 +1,202 @@
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use super::EitherIter;
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use crate::fx::FxHashMap;
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use arrayvec::ArrayVec;
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use std::borrow::Borrow;
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use std::fmt;
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use std::hash::Hash;
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use std::iter::FromIterator;
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use std::ops::Index;
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/// Small-storage-optimized implementation of a map
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/// made specifically for caching results.
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/// Small-storage-optimized implementation of a map.
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///
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/// Stores elements in a small array up to a certain length
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/// and switches to `HashMap` when that length is exceeded.
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///
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/// Implements subset of HashMap API.
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///
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/// Missing HashMap API:
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/// all hasher-related
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/// try_reserve (unstable)
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/// shrink_to (unstable)
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/// drain_filter (unstable)
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/// into_keys/into_values (unstable)
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/// all raw_entry-related
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/// PartialEq/Eq (requires sorting the array)
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/// Entry::or_insert_with_key (unstable)
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/// Vacant/Occupied entries and related
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#[derive(Clone)]
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pub enum SsoHashMap<K, V> {
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Array(ArrayVec<[(K, V); 8]>),
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Map(FxHashMap<K, V>),
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}
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impl<K: Eq + Hash, V> SsoHashMap<K, V> {
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impl<K, V> SsoHashMap<K, V> {
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/// Creates an empty `SsoHashMap`.
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pub fn new() -> Self {
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SsoHashMap::Array(ArrayVec::new())
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}
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/// Inserts or updates value in the map.
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pub fn insert(&mut self, key: K, value: V) {
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/// Creates an empty `SsoHashMap` with the specified capacity.
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pub fn with_capacity(cap: usize) -> Self {
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let array = ArrayVec::new();
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if array.capacity() >= cap {
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SsoHashMap::Array(array)
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} else {
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SsoHashMap::Map(FxHashMap::with_capacity_and_hasher(cap, Default::default()))
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}
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}
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/// Clears the map, removing all key-value pairs. Keeps the allocated memory
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/// for reuse.
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pub fn clear(&mut self) {
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match self {
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SsoHashMap::Array(array) => array.clear(),
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SsoHashMap::Map(map) => map.clear(),
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}
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}
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/// Returns the number of elements the map can hold without reallocating.
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pub fn capacity(&self) -> usize {
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match self {
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SsoHashMap::Array(array) => array.capacity(),
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SsoHashMap::Map(map) => map.capacity(),
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}
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}
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/// Returns the number of elements in the map.
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pub fn len(&self) -> usize {
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match self {
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SsoHashMap::Array(array) => array.len(),
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SsoHashMap::Map(map) => map.len(),
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}
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}
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/// Returns `true` if the map contains no elements.
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pub fn is_empty(&self) -> bool {
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match self {
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SsoHashMap::Array(array) => array.is_empty(),
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SsoHashMap::Map(map) => map.is_empty(),
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}
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}
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/// An iterator visiting all key-value pairs in arbitrary order.
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/// The iterator element type is `(&'a K, &'a V)`.
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pub fn iter(&self) -> impl Iterator<Item = (&'_ K, &'_ V)> {
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self.into_iter()
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}
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/// An iterator visiting all key-value pairs in arbitrary order,
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/// with mutable references to the values.
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/// The iterator element type is `(&'a K, &'a mut V)`.
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pub fn iter_mut(&mut self) -> impl Iterator<Item = (&'_ K, &'_ mut V)> {
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self.into_iter()
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}
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/// An iterator visiting all keys in arbitrary order.
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/// The iterator element type is `&'a K`.
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pub fn keys(&self) -> impl Iterator<Item = &'_ K> {
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match self {
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SsoHashMap::Array(array) => EitherIter::Left(array.iter().map(|(k, _v)| k)),
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SsoHashMap::Map(map) => EitherIter::Right(map.keys()),
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}
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}
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/// An iterator visiting all values in arbitrary order.
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/// The iterator element type is `&'a V`.
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pub fn values(&self) -> impl Iterator<Item = &'_ V> {
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match self {
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SsoHashMap::Array(array) => EitherIter::Left(array.iter().map(|(_k, v)| v)),
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SsoHashMap::Map(map) => EitherIter::Right(map.values()),
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}
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}
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/// An iterator visiting all values mutably in arbitrary order.
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/// The iterator element type is `&'a mut V`.
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pub fn values_mut(&mut self) -> impl Iterator<Item = &'_ mut V> {
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match self {
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SsoHashMap::Array(array) => EitherIter::Left(array.iter_mut().map(|(_k, v)| v)),
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SsoHashMap::Map(map) => EitherIter::Right(map.values_mut()),
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}
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}
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/// Clears the map, returning all key-value pairs as an iterator. Keeps the
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/// allocated memory for reuse.
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pub fn drain(&mut self) -> impl Iterator<Item = (K, V)> + '_ {
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match self {
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SsoHashMap::Array(array) => EitherIter::Left(array.drain(..)),
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SsoHashMap::Map(map) => EitherIter::Right(map.drain()),
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}
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}
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}
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impl<K: Eq + Hash, V> SsoHashMap<K, V> {
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/// Changes underlying storage from array to hashmap
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/// if array is full.
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fn migrate_if_full(&mut self) {
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if let SsoHashMap::Array(array) = self {
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if array.is_full() {
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*self = SsoHashMap::Map(array.drain(..).collect());
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}
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}
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}
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/// Reserves capacity for at least `additional` more elements to be inserted
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/// in the `SsoHashMap`. The collection may reserve more space to avoid
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/// frequent reallocations.
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pub fn reserve(&mut self, additional: usize) {
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match self {
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SsoHashMap::Array(array) => {
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for pair in array.iter_mut() {
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if pair.0 == key {
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pair.1 = value;
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return;
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if array.capacity() < (array.len() + additional) {
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let mut map: FxHashMap<K, V> = array.drain(..).collect();
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map.reserve(additional);
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*self = SsoHashMap::Map(map);
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}
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}
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SsoHashMap::Map(map) => map.reserve(additional),
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}
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}
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/// Shrinks the capacity of the map as much as possible. It will drop
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/// down as much as possible while maintaining the internal rules
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/// and possibly leaving some space in accordance with the resize policy.
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pub fn shrink_to_fit(&mut self) {
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if let SsoHashMap::Map(map) = self {
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let mut array = ArrayVec::new();
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if map.len() <= array.capacity() {
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array.extend(map.drain());
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*self = SsoHashMap::Array(array);
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} else {
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map.shrink_to_fit();
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}
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}
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}
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/// Retains only the elements specified by the predicate.
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pub fn retain<F>(&mut self, mut f: F)
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where
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F: FnMut(&K, &mut V) -> bool,
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{
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match self {
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SsoHashMap::Array(array) => array.retain(|(k, v)| f(k, v)),
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SsoHashMap::Map(map) => map.retain(f),
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}
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}
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/// Inserts a key-value pair into the map.
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///
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/// If the map did not have this key present, [`None`] is returned.
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///
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/// If the map did have this key present, the value is updated, and the old
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/// value is returned. The key is not updated, though; this matters for
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/// types that can be `==` without being identical. See the [module-level
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/// documentation] for more.
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pub fn insert(&mut self, key: K, value: V) -> Option<V> {
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match self {
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SsoHashMap::Array(array) => {
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for (k, v) in array.iter_mut() {
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if *k == key {
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let old_value = std::mem::replace(v, value);
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return Some(old_value);
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}
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}
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if let Err(error) = array.try_push((key, value)) {
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@ -35,27 +205,325 @@ impl<K: Eq + Hash, V> SsoHashMap<K, V> {
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map.insert(key, value);
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*self = SsoHashMap::Map(map);
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}
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None
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}
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SsoHashMap::Map(map) => {
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map.insert(key, value);
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}
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SsoHashMap::Map(map) => map.insert(key, value),
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}
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}
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/// Return value by key if any.
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pub fn get(&self, key: &K) -> Option<&V> {
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/// Removes a key from the map, returning the value at the key if the key
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/// was previously in the map.
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pub fn remove<Q: ?Sized>(&mut self, key: &Q) -> Option<V>
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where
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K: Borrow<Q>,
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Q: Hash + Eq,
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{
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match self {
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SsoHashMap::Array(array) => {
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for pair in array {
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if pair.0 == *key {
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return Some(&pair.1);
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if let Some(index) = array.iter().position(|(k, _v)| k.borrow() == key) {
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Some(array.swap_remove(index).1)
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} else {
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None
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}
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}
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SsoHashMap::Map(map) => map.remove(key),
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}
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}
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/// Removes a key from the map, returning the stored key and value if the
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/// key was previously in the map.
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pub fn remove_entry<Q: ?Sized>(&mut self, key: &Q) -> Option<(K, V)>
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where
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K: Borrow<Q>,
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Q: Hash + Eq,
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{
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match self {
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SsoHashMap::Array(array) => {
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if let Some(index) = array.iter().position(|(k, _v)| k.borrow() == key) {
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Some(array.swap_remove(index))
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} else {
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None
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}
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}
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SsoHashMap::Map(map) => map.remove_entry(key),
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}
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}
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/// Returns a reference to the value corresponding to the key.
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pub fn get<Q: ?Sized>(&self, key: &Q) -> Option<&V>
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where
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K: Borrow<Q>,
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Q: Hash + Eq,
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{
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match self {
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SsoHashMap::Array(array) => {
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for (k, v) in array {
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if k.borrow() == key {
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return Some(v);
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}
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}
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return None;
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None
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}
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SsoHashMap::Map(map) => {
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return map.get(key);
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SsoHashMap::Map(map) => map.get(key),
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}
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}
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/// Returns a mutable reference to the value corresponding to the key.
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pub fn get_mut<Q: ?Sized>(&mut self, key: &Q) -> Option<&mut V>
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where
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K: Borrow<Q>,
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Q: Hash + Eq,
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{
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match self {
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SsoHashMap::Array(array) => {
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for (k, v) in array {
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if (*k).borrow() == key {
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return Some(v);
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}
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}
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None
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}
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SsoHashMap::Map(map) => map.get_mut(key),
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}
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}
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/// Returns the key-value pair corresponding to the supplied key.
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pub fn get_key_value<Q: ?Sized>(&self, key: &Q) -> Option<(&K, &V)>
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where
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K: Borrow<Q>,
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Q: Hash + Eq,
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{
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match self {
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SsoHashMap::Array(array) => {
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for (k, v) in array {
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if k.borrow() == key {
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return Some((k, v));
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}
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}
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None
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}
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SsoHashMap::Map(map) => map.get_key_value(key),
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}
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}
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/// Returns `true` if the map contains a value for the specified key.
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pub fn contains_key<Q: ?Sized>(&self, key: &Q) -> bool
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where
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K: Borrow<Q>,
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Q: Hash + Eq,
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{
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match self {
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SsoHashMap::Array(array) => array.iter().any(|(k, _v)| k.borrow() == key),
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SsoHashMap::Map(map) => map.contains_key(key),
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}
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}
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/// Gets the given key's corresponding entry in the map for in-place manipulation.
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pub fn entry(&mut self, key: K) -> Entry<'_, K, V> {
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Entry { ssomap: self, key }
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}
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}
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impl<K, V> Default for SsoHashMap<K, V> {
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fn default() -> Self {
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Self::new()
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}
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}
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impl<K: Eq + Hash, V> FromIterator<(K, V)> for SsoHashMap<K, V> {
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fn from_iter<I: IntoIterator<Item = (K, V)>>(iter: I) -> SsoHashMap<K, V> {
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let mut map: SsoHashMap<K, V> = Default::default();
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map.extend(iter);
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map
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}
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}
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impl<K: Eq + Hash, V> Extend<(K, V)> for SsoHashMap<K, V> {
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fn extend<I>(&mut self, iter: I)
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where
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I: IntoIterator<Item = (K, V)>,
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{
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for (key, value) in iter.into_iter() {
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self.insert(key, value);
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}
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}
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fn extend_one(&mut self, (k, v): (K, V)) {
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self.insert(k, v);
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}
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fn extend_reserve(&mut self, additional: usize) {
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match self {
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SsoHashMap::Array(array) => {
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if array.capacity() < (array.len() + additional) {
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let mut map: FxHashMap<K, V> = array.drain(..).collect();
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map.extend_reserve(additional);
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*self = SsoHashMap::Map(map);
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}
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}
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SsoHashMap::Map(map) => map.extend_reserve(additional),
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}
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}
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}
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impl<'a, K, V> Extend<(&'a K, &'a V)> for SsoHashMap<K, V>
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where
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K: Eq + Hash + Copy,
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V: Copy,
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{
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fn extend<T: IntoIterator<Item = (&'a K, &'a V)>>(&mut self, iter: T) {
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self.extend(iter.into_iter().map(|(k, v)| (k.clone(), v.clone())))
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}
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fn extend_one(&mut self, (&k, &v): (&'a K, &'a V)) {
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self.insert(k, v);
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}
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fn extend_reserve(&mut self, additional: usize) {
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Extend::<(K, V)>::extend_reserve(self, additional)
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}
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}
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impl<K, V> IntoIterator for SsoHashMap<K, V> {
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type IntoIter = EitherIter<
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<ArrayVec<[(K, V); 8]> as IntoIterator>::IntoIter,
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<FxHashMap<K, V> as IntoIterator>::IntoIter,
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>;
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type Item = <Self::IntoIter as Iterator>::Item;
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fn into_iter(self) -> Self::IntoIter {
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match self {
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SsoHashMap::Array(array) => EitherIter::Left(array.into_iter()),
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SsoHashMap::Map(map) => EitherIter::Right(map.into_iter()),
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}
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}
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}
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/// adapts Item of array reference iterator to Item of hashmap reference iterator.
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fn adapt_array_ref_it<K, V>(pair: &'a (K, V)) -> (&'a K, &'a V) {
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let (a, b) = pair;
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(a, b)
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}
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/// adapts Item of array mut reference iterator to Item of hashmap mut reference iterator.
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fn adapt_array_mut_it<K, V>(pair: &'a mut (K, V)) -> (&'a K, &'a mut V) {
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let (a, b) = pair;
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(a, b)
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}
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impl<'a, K, V> IntoIterator for &'a SsoHashMap<K, V> {
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type IntoIter = EitherIter<
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std::iter::Map<
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<&'a ArrayVec<[(K, V); 8]> as IntoIterator>::IntoIter,
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fn(&'a (K, V)) -> (&'a K, &'a V),
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>,
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<&'a FxHashMap<K, V> as IntoIterator>::IntoIter,
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>;
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type Item = <Self::IntoIter as Iterator>::Item;
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fn into_iter(self) -> Self::IntoIter {
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match self {
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SsoHashMap::Array(array) => EitherIter::Left(array.into_iter().map(adapt_array_ref_it)),
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SsoHashMap::Map(map) => EitherIter::Right(map.into_iter()),
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}
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}
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}
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impl<'a, K, V> IntoIterator for &'a mut SsoHashMap<K, V> {
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type IntoIter = EitherIter<
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std::iter::Map<
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<&'a mut ArrayVec<[(K, V); 8]> as IntoIterator>::IntoIter,
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fn(&'a mut (K, V)) -> (&'a K, &'a mut V),
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>,
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<&'a mut FxHashMap<K, V> as IntoIterator>::IntoIter,
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>;
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type Item = <Self::IntoIter as Iterator>::Item;
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fn into_iter(self) -> Self::IntoIter {
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match self {
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SsoHashMap::Array(array) => EitherIter::Left(array.into_iter().map(adapt_array_mut_it)),
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SsoHashMap::Map(map) => EitherIter::Right(map.into_iter()),
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}
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}
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||||
}
|
||||
|
||||
impl<K, V> fmt::Debug for SsoHashMap<K, V>
|
||||
where
|
||||
K: fmt::Debug,
|
||||
V: fmt::Debug,
|
||||
{
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
f.debug_map().entries(self.iter()).finish()
|
||||
}
|
||||
}
|
||||
|
||||
impl<'a, K, Q: ?Sized, V> Index<&'a Q> for SsoHashMap<K, V>
|
||||
where
|
||||
K: Eq + Hash + Borrow<Q>,
|
||||
Q: Eq + Hash,
|
||||
{
|
||||
type Output = V;
|
||||
|
||||
fn index(&self, key: &Q) -> &V {
|
||||
self.get(key).expect("no entry found for key")
|
||||
}
|
||||
}
|
||||
|
||||
/// A view into a single entry in a map.
|
||||
pub struct Entry<'a, K, V> {
|
||||
ssomap: &'a mut SsoHashMap<K, V>,
|
||||
key: K,
|
||||
}
|
||||
|
||||
impl<'a, K: Eq + Hash, V> Entry<'a, K, V> {
|
||||
/// Provides in-place mutable access to an occupied entry before any
|
||||
/// potential inserts into the map.
|
||||
pub fn and_modify<F>(self, f: F) -> Self
|
||||
where
|
||||
F: FnOnce(&mut V),
|
||||
{
|
||||
if let Some(value) = self.ssomap.get_mut(&self.key) {
|
||||
f(value);
|
||||
}
|
||||
self
|
||||
}
|
||||
|
||||
/// Ensures a value is in the entry by inserting the default if empty, and returns
|
||||
/// a mutable reference to the value in the entry.
|
||||
pub fn or_insert(self, value: V) -> &'a mut V {
|
||||
self.or_insert_with(|| value)
|
||||
}
|
||||
|
||||
/// Ensures a value is in the entry by inserting the result of the default function if empty,
|
||||
/// and returns a mutable reference to the value in the entry.
|
||||
pub fn or_insert_with<F: FnOnce() -> V>(self, default: F) -> &'a mut V {
|
||||
self.ssomap.migrate_if_full();
|
||||
match self.ssomap {
|
||||
SsoHashMap::Array(array) => {
|
||||
let key_ref = &self.key;
|
||||
let found_index = array.iter().position(|(k, _v)| k == key_ref);
|
||||
let index = if let Some(index) = found_index {
|
||||
index
|
||||
} else {
|
||||
array.try_push((self.key, default())).unwrap();
|
||||
array.len() - 1
|
||||
};
|
||||
&mut array[index].1
|
||||
}
|
||||
SsoHashMap::Map(map) => map.entry(self.key).or_insert_with(default),
|
||||
}
|
||||
}
|
||||
|
||||
/// Returns a reference to this entry's key.
|
||||
pub fn key(&self) -> &K {
|
||||
&self.key
|
||||
}
|
||||
}
|
||||
|
||||
impl<'a, K: Eq + Hash, V: Default> Entry<'a, K, V> {
|
||||
/// Ensures a value is in the entry by inserting the default value if empty,
|
||||
/// and returns a mutable reference to the value in the entry.
|
||||
pub fn or_default(self) -> &'a mut V {
|
||||
self.or_insert_with(Default::default)
|
||||
}
|
||||
}
|
||||
|
|
|
|||
|
|
@ -1,3 +1,75 @@
|
|||
use std::fmt;
|
||||
use std::iter::ExactSizeIterator;
|
||||
use std::iter::FusedIterator;
|
||||
use std::iter::Iterator;
|
||||
|
||||
/// Iterator which may contain instance of
|
||||
/// one of two specific implementations.
|
||||
///
|
||||
/// Used by both SsoHashMap and SsoHashSet.
|
||||
#[derive(Clone)]
|
||||
pub enum EitherIter<L, R> {
|
||||
Left(L),
|
||||
Right(R),
|
||||
}
|
||||
|
||||
impl<L, R> Iterator for EitherIter<L, R>
|
||||
where
|
||||
L: Iterator,
|
||||
R: Iterator<Item = L::Item>,
|
||||
{
|
||||
type Item = L::Item;
|
||||
|
||||
fn next(&mut self) -> Option<Self::Item> {
|
||||
match self {
|
||||
EitherIter::Left(l) => l.next(),
|
||||
EitherIter::Right(r) => r.next(),
|
||||
}
|
||||
}
|
||||
|
||||
fn size_hint(&self) -> (usize, Option<usize>) {
|
||||
match self {
|
||||
EitherIter::Left(l) => l.size_hint(),
|
||||
EitherIter::Right(r) => r.size_hint(),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<L, R> ExactSizeIterator for EitherIter<L, R>
|
||||
where
|
||||
L: ExactSizeIterator,
|
||||
R: ExactSizeIterator,
|
||||
EitherIter<L, R>: Iterator,
|
||||
{
|
||||
fn len(&self) -> usize {
|
||||
match self {
|
||||
EitherIter::Left(l) => l.len(),
|
||||
EitherIter::Right(r) => r.len(),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<L, R> FusedIterator for EitherIter<L, R>
|
||||
where
|
||||
L: FusedIterator,
|
||||
R: FusedIterator,
|
||||
EitherIter<L, R>: Iterator,
|
||||
{
|
||||
}
|
||||
|
||||
impl<L, R> fmt::Debug for EitherIter<L, R>
|
||||
where
|
||||
L: fmt::Debug,
|
||||
R: fmt::Debug,
|
||||
{
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
match self {
|
||||
EitherIter::Left(l) => l.fmt(f),
|
||||
EitherIter::Right(r) => r.fmt(f),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
mod map;
|
||||
mod set;
|
||||
|
||||
|
|
|
|||
|
|
@ -1,26 +1,197 @@
|
|||
use super::EitherIter;
|
||||
use crate::fx::FxHashSet;
|
||||
use arrayvec::ArrayVec;
|
||||
use std::borrow::Borrow;
|
||||
use std::fmt;
|
||||
use std::hash::Hash;
|
||||
use std::iter::FromIterator;
|
||||
|
||||
/// Small-storage-optimized implementation of a set.
|
||||
///
|
||||
/// Stores elements in a small array up to a certain length
|
||||
/// and switches to `HashSet` when that length is exceeded.
|
||||
///
|
||||
/// Implements subset of HashSet API.
|
||||
///
|
||||
/// Missing HashSet API:
|
||||
/// all hasher-related
|
||||
/// try_reserve (unstable)
|
||||
/// shrink_to (unstable)
|
||||
/// drain_filter (unstable)
|
||||
/// get_or_insert/get_or_insert_owned/get_or_insert_with (unstable)
|
||||
/// difference/symmetric_difference/intersection/union
|
||||
/// is_disjoint/is_subset/is_superset
|
||||
/// PartialEq/Eq (requires sorting the array)
|
||||
/// BitOr/BitAnd/BitXor/Sub
|
||||
#[derive(Clone)]
|
||||
pub enum SsoHashSet<T> {
|
||||
Array(ArrayVec<[T; 8]>),
|
||||
Set(FxHashSet<T>),
|
||||
}
|
||||
|
||||
impl<T: Eq + Hash> SsoHashSet<T> {
|
||||
impl<T> SsoHashSet<T> {
|
||||
/// Creates an empty `SsoHashSet`.
|
||||
pub fn new() -> Self {
|
||||
SsoHashSet::Array(ArrayVec::new())
|
||||
}
|
||||
|
||||
/// Creates an empty `SsoHashSet` with the specified capacity.
|
||||
pub fn with_capacity(cap: usize) -> Self {
|
||||
let array = ArrayVec::new();
|
||||
if array.capacity() >= cap {
|
||||
SsoHashSet::Array(array)
|
||||
} else {
|
||||
SsoHashSet::Set(FxHashSet::with_capacity_and_hasher(cap, Default::default()))
|
||||
}
|
||||
}
|
||||
|
||||
/// Clears the set, removing all values.
|
||||
pub fn clear(&mut self) {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => array.clear(),
|
||||
SsoHashSet::Set(set) => set.clear(),
|
||||
}
|
||||
}
|
||||
|
||||
/// Returns the number of elements the set can hold without reallocating.
|
||||
pub fn capacity(&self) -> usize {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => array.capacity(),
|
||||
SsoHashSet::Set(set) => set.capacity(),
|
||||
}
|
||||
}
|
||||
|
||||
/// Returns the number of elements in the set.
|
||||
pub fn len(&self) -> usize {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => array.len(),
|
||||
SsoHashSet::Set(set) => set.len(),
|
||||
}
|
||||
}
|
||||
|
||||
/// Returns `true` if the set contains no elements.
|
||||
pub fn is_empty(&self) -> bool {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => array.is_empty(),
|
||||
SsoHashSet::Set(set) => set.is_empty(),
|
||||
}
|
||||
}
|
||||
|
||||
/// An iterator visiting all elements in arbitrary order.
|
||||
/// The iterator element type is `&'a T`.
|
||||
pub fn iter(&'a self) -> impl Iterator<Item = &'a T> {
|
||||
self.into_iter()
|
||||
}
|
||||
|
||||
/// Clears the set, returning all elements in an iterator.
|
||||
pub fn drain(&mut self) -> impl Iterator<Item = T> + '_ {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => EitherIter::Left(array.drain(..)),
|
||||
SsoHashSet::Set(set) => EitherIter::Right(set.drain()),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<T: Eq + Hash> SsoHashSet<T> {
|
||||
/// Reserves capacity for at least `additional` more elements to be inserted
|
||||
/// in the `SsoHashSet`. The collection may reserve more space to avoid
|
||||
/// frequent reallocations.
|
||||
pub fn reserve(&mut self, additional: usize) {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => {
|
||||
if array.capacity() < (array.len() + additional) {
|
||||
let mut set: FxHashSet<T> = array.drain(..).collect();
|
||||
set.reserve(additional);
|
||||
*self = SsoHashSet::Set(set);
|
||||
}
|
||||
}
|
||||
SsoHashSet::Set(set) => set.reserve(additional),
|
||||
}
|
||||
}
|
||||
|
||||
/// Shrinks the capacity of the set as much as possible. It will drop
|
||||
/// down as much as possible while maintaining the internal rules
|
||||
/// and possibly leaving some space in accordance with the resize policy.
|
||||
pub fn shrink_to_fit(&mut self) {
|
||||
if let SsoHashSet::Set(set) = self {
|
||||
let mut array = ArrayVec::new();
|
||||
if set.len() <= array.capacity() {
|
||||
array.extend(set.drain());
|
||||
*self = SsoHashSet::Array(array);
|
||||
} else {
|
||||
set.shrink_to_fit();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// Retains only the elements specified by the predicate.
|
||||
pub fn retain<F>(&mut self, mut f: F)
|
||||
where
|
||||
F: FnMut(&T) -> bool,
|
||||
{
|
||||
match self {
|
||||
SsoHashSet::Array(array) => array.retain(|v| f(v)),
|
||||
SsoHashSet::Set(set) => set.retain(f),
|
||||
}
|
||||
}
|
||||
|
||||
/// Removes and returns the value in the set, if any, that is equal to the given one.
|
||||
pub fn take<Q: ?Sized>(&mut self, value: &Q) -> Option<T>
|
||||
where
|
||||
T: Borrow<Q>,
|
||||
Q: Hash + Eq,
|
||||
{
|
||||
match self {
|
||||
SsoHashSet::Array(array) => {
|
||||
if let Some(index) = array.iter().position(|val| val.borrow() == value) {
|
||||
Some(array.swap_remove(index))
|
||||
} else {
|
||||
None
|
||||
}
|
||||
}
|
||||
SsoHashSet::Set(set) => set.take(value),
|
||||
}
|
||||
}
|
||||
|
||||
/// Adds a value to the set, replacing the existing value, if any, that is equal to the given
|
||||
/// one. Returns the replaced value.
|
||||
pub fn replace(&mut self, value: T) -> Option<T> {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => {
|
||||
if let Some(index) = array.iter().position(|val| *val == value) {
|
||||
let old_value = std::mem::replace(&mut array[index], value);
|
||||
Some(old_value)
|
||||
} else {
|
||||
None
|
||||
}
|
||||
}
|
||||
SsoHashSet::Set(set) => set.replace(value),
|
||||
}
|
||||
}
|
||||
|
||||
/// Returns a reference to the value in the set, if any, that is equal to the given value.
|
||||
pub fn get<Q: ?Sized>(&self, value: &Q) -> Option<&T>
|
||||
where
|
||||
T: Borrow<Q>,
|
||||
Q: Hash + Eq,
|
||||
{
|
||||
match self {
|
||||
SsoHashSet::Array(array) => {
|
||||
if let Some(index) = array.iter().position(|val| val.borrow() == value) {
|
||||
Some(&array[index])
|
||||
} else {
|
||||
None
|
||||
}
|
||||
}
|
||||
SsoHashSet::Set(set) => set.get(value),
|
||||
}
|
||||
}
|
||||
|
||||
/// Adds a value to the set.
|
||||
///
|
||||
/// If the set did not have this value present, true is returned.
|
||||
/// If the set did not have this value present, `true` is returned.
|
||||
///
|
||||
/// If the set did have this value present, false is returned.
|
||||
/// If the set did have this value present, `false` is returned.
|
||||
pub fn insert(&mut self, elem: T) -> bool {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => {
|
||||
|
|
@ -38,4 +209,134 @@ impl<T: Eq + Hash> SsoHashSet<T> {
|
|||
SsoHashSet::Set(set) => set.insert(elem),
|
||||
}
|
||||
}
|
||||
|
||||
/// Removes a value from the set. Returns whether the value was
|
||||
/// present in the set.
|
||||
pub fn remove<Q: ?Sized>(&mut self, value: &Q) -> bool
|
||||
where
|
||||
T: Borrow<Q>,
|
||||
Q: Hash + Eq,
|
||||
{
|
||||
match self {
|
||||
SsoHashSet::Array(array) => {
|
||||
if let Some(index) = array.iter().position(|val| val.borrow() == value) {
|
||||
array.swap_remove(index);
|
||||
true
|
||||
} else {
|
||||
false
|
||||
}
|
||||
}
|
||||
SsoHashSet::Set(set) => set.remove(value),
|
||||
}
|
||||
}
|
||||
|
||||
/// Returns `true` if the set contains a value.
|
||||
pub fn contains<Q: ?Sized>(&self, value: &Q) -> bool
|
||||
where
|
||||
T: Borrow<Q>,
|
||||
Q: Hash + Eq,
|
||||
{
|
||||
match self {
|
||||
SsoHashSet::Array(array) => array.iter().any(|v| v.borrow() == value),
|
||||
SsoHashSet::Set(set) => set.contains(value),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<T> Default for SsoHashSet<T> {
|
||||
fn default() -> Self {
|
||||
Self::new()
|
||||
}
|
||||
}
|
||||
|
||||
impl<T: Eq + Hash> FromIterator<T> for SsoHashSet<T> {
|
||||
fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> SsoHashSet<T> {
|
||||
let mut set: SsoHashSet<T> = Default::default();
|
||||
set.extend(iter);
|
||||
set
|
||||
}
|
||||
}
|
||||
|
||||
impl<T: Eq + Hash> Extend<T> for SsoHashSet<T> {
|
||||
fn extend<I>(&mut self, iter: I)
|
||||
where
|
||||
I: IntoIterator<Item = T>,
|
||||
{
|
||||
for val in iter.into_iter() {
|
||||
self.insert(val);
|
||||
}
|
||||
}
|
||||
|
||||
fn extend_one(&mut self, item: T) {
|
||||
self.insert(item);
|
||||
}
|
||||
|
||||
fn extend_reserve(&mut self, additional: usize) {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => {
|
||||
if array.capacity() < (array.len() + additional) {
|
||||
let mut set: FxHashSet<T> = array.drain(..).collect();
|
||||
set.extend_reserve(additional);
|
||||
*self = SsoHashSet::Set(set);
|
||||
}
|
||||
}
|
||||
SsoHashSet::Set(set) => set.extend_reserve(additional),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'a, T> Extend<&'a T> for SsoHashSet<T>
|
||||
where
|
||||
T: 'a + Eq + Hash + Copy,
|
||||
{
|
||||
fn extend<I: IntoIterator<Item = &'a T>>(&mut self, iter: I) {
|
||||
self.extend(iter.into_iter().cloned());
|
||||
}
|
||||
|
||||
fn extend_one(&mut self, &item: &'a T) {
|
||||
self.insert(item);
|
||||
}
|
||||
|
||||
fn extend_reserve(&mut self, additional: usize) {
|
||||
Extend::<T>::extend_reserve(self, additional)
|
||||
}
|
||||
}
|
||||
|
||||
impl<T> IntoIterator for SsoHashSet<T> {
|
||||
type IntoIter = EitherIter<
|
||||
<ArrayVec<[T; 8]> as IntoIterator>::IntoIter,
|
||||
<FxHashSet<T> as IntoIterator>::IntoIter,
|
||||
>;
|
||||
type Item = <Self::IntoIter as Iterator>::Item;
|
||||
|
||||
fn into_iter(self) -> Self::IntoIter {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => EitherIter::Left(array.into_iter()),
|
||||
SsoHashSet::Set(set) => EitherIter::Right(set.into_iter()),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'a, T> IntoIterator for &'a SsoHashSet<T> {
|
||||
type IntoIter = EitherIter<
|
||||
<&'a ArrayVec<[T; 8]> as IntoIterator>::IntoIter,
|
||||
<&'a FxHashSet<T> as IntoIterator>::IntoIter,
|
||||
>;
|
||||
type Item = <Self::IntoIter as Iterator>::Item;
|
||||
|
||||
fn into_iter(self) -> Self::IntoIter {
|
||||
match self {
|
||||
SsoHashSet::Array(array) => EitherIter::Left(array.into_iter()),
|
||||
SsoHashSet::Set(set) => EitherIter::Right(set.into_iter()),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<T> fmt::Debug for SsoHashSet<T>
|
||||
where
|
||||
T: fmt::Debug,
|
||||
{
|
||||
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
|
||||
f.debug_set().entries(self.iter()).finish()
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue