| //! A hash map where the keys and values are both held by weak pointers, and keys are compared by |
| //! pointer. |
| |
| use std::collections::hash_map::RandomState; |
| use std::fmt::{self, Debug}; |
| use std::hash::BuildHasher; |
| use std::iter::FromIterator; |
| use std::ops::Deref; |
| |
| use super::by_ptr::*; |
| use super::traits::*; |
| use super::weak_weak_hash_map as base; |
| |
| pub use super::PtrWeakWeakHashMap; |
| pub use super::weak_weak_hash_map::{Entry, Iter, Keys, Values, Drain, IntoIter}; |
| |
| impl <K: WeakElement, V: WeakElement> PtrWeakWeakHashMap<K, V, RandomState> |
| where K::Strong: Deref |
| { |
| /// Creates an empty `PtrWeakWeakHashMap`. |
| pub fn new() -> Self { |
| PtrWeakWeakHashMap(base::WeakWeakHashMap::new()) |
| } |
| |
| /// Creates an empty `PtrWeakWeakHashMap` with the given capacity. |
| pub fn with_capacity(capacity: usize) -> Self { |
| PtrWeakWeakHashMap(base::WeakWeakHashMap::with_capacity(capacity)) |
| } |
| } |
| |
| impl <K: WeakElement, V: WeakElement, S: BuildHasher> PtrWeakWeakHashMap<K, V, S> |
| where K::Strong: Deref |
| { |
| /// Creates an empty `PtrWeakWeakHashMap` with the given capacity and hasher. |
| pub fn with_hasher(hash_builder: S) -> Self { |
| PtrWeakWeakHashMap(base::WeakWeakHashMap::with_hasher(hash_builder)) |
| } |
| |
| /// Creates an empty `PtrWeakWeakHashMap` with the given capacity and hasher. |
| pub fn with_capacity_and_hasher(capacity: usize, hash_builder: S) -> Self { |
| PtrWeakWeakHashMap(base::WeakWeakHashMap::with_capacity_and_hasher(capacity, hash_builder)) |
| } |
| |
| /// Returns a reference to the map's `BuildHasher`. |
| pub fn hasher(&self) -> &S { |
| self.0.hasher() |
| } |
| |
| /// Returns the number of elements the map can hold without reallocating. |
| pub fn capacity(&self) -> usize { |
| self.0.capacity() |
| } |
| |
| /// Removes all mappings whose keys have expired. |
| pub fn remove_expired(&mut self) { |
| self.0.remove_expired() |
| } |
| |
| /// Reserves room for additional elements. |
| pub fn reserve(&mut self, additional_capacity: usize) { |
| self.0.reserve(additional_capacity) |
| } |
| |
| /// Shrinks the capacity to the minimum allowed to hold the current number of elements. |
| pub fn shrink_to_fit(&mut self) { |
| self.0.shrink_to_fit() |
| } |
| |
| /// Returns an over-approximation of the number of elements. |
| pub fn len(&self) -> usize { |
| self.0.len() |
| } |
| |
| /// Is the map empty? |
| /// |
| /// Note that this may return false even if all keys in the map have |
| /// expired, if they haven't been collected yet. |
| pub fn is_empty(&self) -> bool { |
| self.0.is_empty() |
| } |
| |
| /// The proportion of buckets that are used. |
| /// |
| /// This is an over-approximation because of expired keys. |
| pub fn load_factor(&self) -> f32 { |
| self.0.load_factor() |
| } |
| |
| /// Gets the requested entry. |
| pub fn entry(&mut self, key: K::Strong) -> Entry<ByPtr<K>, V> { |
| self.0.entry(key) |
| } |
| |
| /// Removes all associations from the map. |
| pub fn clear(&mut self) { |
| self.0.clear() |
| } |
| |
| /// Returns a reference to the value corresponding to the key. |
| pub fn get(&self, key: &K::Strong) -> Option<V::Strong> { |
| self.0.get(&(key.deref() as *const _)) |
| } |
| |
| /// Returns true if the map contains the specified key. |
| pub fn contains_key(&self, key: &K::Strong) -> bool { |
| self.0.contains_key(&(key.deref() as *const _)) |
| } |
| |
| /// Unconditionally inserts the value, returning the old value if already present. Does not |
| /// replace the key. |
| pub fn insert(&mut self, key: K::Strong, value: V::Strong) -> Option<V::Strong> { |
| self.0.insert(key, value) |
| } |
| |
| /// Removes the entry with the given key, if it exists, and returns the value. |
| pub fn remove(&mut self, key: &K::Strong) -> Option<V::Strong> { |
| self.0.remove(&(key.deref() as *const _)) |
| } |
| |
| /// Removes all mappings not satisfying the given predicate. |
| /// |
| /// Also removes any expired mappings. |
| pub fn retain<F>(&mut self, f: F) |
| where F: FnMut(K::Strong, V::Strong) -> bool |
| { |
| self.0.retain(f) |
| } |
| |
| /// Is this map a submap of the other, using the given value comparison. |
| /// |
| /// In particular, all the keys of self must be in other and the values must compare true with |
| /// value_equal. |
| pub fn submap_with<F, S1, V1>(&self, other: &PtrWeakWeakHashMap<K, V1, S1>, value_equal: F) -> bool |
| where F: FnMut(V::Strong, V1::Strong) -> bool, |
| V1: WeakElement, |
| S1: BuildHasher |
| { |
| self.0.is_submap_with(&other.0, value_equal) |
| } |
| |
| /// Is self a submap of other? |
| pub fn is_submap<V1, S1>(&self, other: &PtrWeakWeakHashMap<K, V1, S1>) -> bool |
| where V1: WeakElement, |
| V::Strong: PartialEq<V1::Strong>, |
| S1: BuildHasher |
| { |
| self.0.is_submap(&other.0) |
| } |
| |
| /// Are the keys of self a subset of the keys of other? |
| pub fn domain_is_subset<V1, S1>(&self, other: &PtrWeakWeakHashMap<K, V1, S1>) -> bool |
| where V1: WeakElement, |
| S1: BuildHasher |
| { |
| self.0.domain_is_subset(&other.0) |
| } |
| } |
| |
| impl<K: WeakElement, V: WeakElement, S> PtrWeakWeakHashMap<K, V, S> |
| where K::Strong: Deref |
| { |
| /// Gets an iterator over the keys and values. |
| pub fn iter(&self) -> Iter<ByPtr<K>, V> { |
| self.0.iter() |
| } |
| |
| /// Gets an iterator over the keys. |
| pub fn keys(&self) -> Keys<ByPtr<K>, V> { |
| self.0.keys() |
| } |
| |
| /// Gets an iterator over the values. |
| pub fn values(&self) -> Values<ByPtr<K>, V> { |
| self.0.values() |
| } |
| |
| /// Gets a draining iterator, which removes all the values but retains the storage. |
| pub fn drain(&mut self) -> Drain<ByPtr<K>, V> { |
| self.0.drain() |
| } |
| } |
| |
| impl<K, V, V1, S, S1> PartialEq<PtrWeakWeakHashMap<K, V1, S1>> |
| for PtrWeakWeakHashMap<K, V, S> |
| where K: WeakElement, |
| K::Strong: Deref, |
| V: WeakElement, |
| V1: WeakElement, |
| V::Strong: PartialEq<V1::Strong>, |
| S: BuildHasher, |
| S1: BuildHasher |
| { |
| fn eq(&self, other: &PtrWeakWeakHashMap<K, V1, S1>) -> bool { |
| self.0 == other.0 |
| } |
| } |
| |
| impl<K: WeakElement, V: WeakElement, S: BuildHasher> Eq for PtrWeakWeakHashMap<K, V, S> |
| where K::Strong: Deref, |
| V::Strong: Eq |
| { } |
| |
| impl<K: WeakElement, V: WeakElement, S: BuildHasher + Default> Default for PtrWeakWeakHashMap<K, V, S> |
| where K::Strong: Deref |
| { |
| fn default() -> Self { |
| PtrWeakWeakHashMap(base::WeakWeakHashMap::<ByPtr<K>, V, S>::default()) |
| } |
| } |
| |
| impl<K, V, S> FromIterator<(K::Strong, V::Strong)> for PtrWeakWeakHashMap<K, V, S> |
| where K: WeakElement, |
| K::Strong: Deref, |
| V: WeakElement, |
| S: BuildHasher + Default |
| { |
| fn from_iter<T: IntoIterator<Item=(K::Strong, V::Strong)>>(iter: T) -> Self { |
| PtrWeakWeakHashMap(base::WeakWeakHashMap::<ByPtr<K>, V, S>::from_iter(iter)) |
| } |
| } |
| |
| impl<K, V, S> Extend<(K::Strong, V::Strong)> for PtrWeakWeakHashMap<K, V, S> |
| where K: WeakElement, |
| K::Strong: Deref, |
| V: WeakElement, |
| S: BuildHasher |
| { |
| fn extend<T: IntoIterator<Item=(K::Strong, V::Strong)>>(&mut self, iter: T) { |
| self.0.extend(iter) |
| } |
| } |
| |
| impl<K, V, S> Debug for PtrWeakWeakHashMap<K, V, S> |
| where K: WeakElement, |
| K::Strong: Debug, |
| V: WeakElement, |
| V::Strong: Debug |
| { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| self.0.fmt(f) |
| } |
| } |
| |
| impl<K: WeakElement, V: WeakElement, S> IntoIterator for PtrWeakWeakHashMap<K, V, S> { |
| type Item = (K::Strong, V::Strong); |
| type IntoIter = IntoIter<ByPtr<K>, V>; |
| |
| fn into_iter(self) -> Self::IntoIter { |
| self.0.into_iter() |
| } |
| } |
| |
| impl<'a, K: WeakElement, V: WeakElement, S> IntoIterator for &'a PtrWeakWeakHashMap<K, V, S> { |
| type Item = (K::Strong, V::Strong); |
| type IntoIter = Iter<'a, ByPtr<K>, V>; |
| |
| fn into_iter(self) -> Self::IntoIter { |
| (&self.0).into_iter() |
| } |
| } |
| |
| #[cfg(test)] |
| mod test |
| { |
| use crate::PtrWeakWeakHashMap; |
| use crate::weak_weak_hash_map::Entry; |
| use std::rc::{Rc, Weak}; |
| |
| // fn show_me(weakmap: &PtrWeakWeakHashMap<Weak<u32>, Weak<f32>>) { |
| // for (key, _) in weakmap { |
| // eprint!(" {:2}", *key); |
| // } |
| // eprintln!(); |
| // } |
| |
| // From https://github.com/tov/weak-table-rs/issues/1#issuecomment-461858060 |
| #[test] |
| fn insert_and_check() { |
| let mut rcs: Vec<(Rc<u32>, Rc<f32>)> = Vec::new(); |
| |
| for i in 0 .. 200 { |
| rcs.push((Rc::new(i), Rc::new(i as f32 + 0.1))); |
| } |
| |
| let mut weakmap: PtrWeakWeakHashMap<Weak<u32>, Weak<f32>> = PtrWeakWeakHashMap::new(); |
| |
| for (key, value) in rcs.iter().cloned() { |
| weakmap.insert(key, value); |
| // show_me(&weakmap); |
| } |
| |
| let mut count = 0; |
| |
| for (key, value) in &rcs { |
| assert!(weakmap.contains_key(key)); |
| |
| match weakmap.entry(Rc::clone(key)) { |
| Entry::Occupied(occ) => { |
| assert_eq!( occ.get(), value ); |
| count += 1; |
| } |
| Entry::Vacant(_) => { |
| eprintln!("PointerWeakWeakHashMap: missing: {}", *key); |
| } |
| } |
| } |
| |
| assert_eq!( count, rcs.len() ); |
| } |
| } |
| |
| |