| //! A hash map where the keys are held by weak pointers and compared by pointer. |
| |
| use crate::compat::*; |
| |
| use super::by_ptr::*; |
| use super::traits::*; |
| use super::weak_key_hash_map as base; |
| |
| pub use super::PtrWeakKeyHashMap; |
| pub use super::weak_key_hash_map::{Entry, Iter, IterMut, Keys, Values, ValuesMut, Drain, IntoIter}; |
| |
| impl <K: WeakElement, V> PtrWeakKeyHashMap<K, V, RandomState> |
| where K::Strong: Deref |
| { |
| /// Creates an empty `PtrWeakKeyHashMap`. |
| /// |
| /// *O*(1) time |
| pub fn new() -> Self { |
| PtrWeakKeyHashMap(base::WeakKeyHashMap::new()) |
| } |
| |
| /// Creates an empty `PtrWeakKeyHashMap` with the given capacity. |
| /// |
| /// *O*(*n*) time |
| pub fn with_capacity(capacity: usize) -> Self { |
| PtrWeakKeyHashMap(base::WeakKeyHashMap::with_capacity(capacity)) |
| } |
| } |
| |
| impl <K: WeakElement, V, S: BuildHasher> PtrWeakKeyHashMap<K, V, S> |
| where K::Strong: Deref |
| { |
| /// Creates an empty `PtrWeakKeyHashMap` with the given capacity and hasher. |
| /// |
| /// *O*(*n*) time |
| pub fn with_hasher(hash_builder: S) -> Self { |
| PtrWeakKeyHashMap(base::WeakKeyHashMap::with_hasher(hash_builder)) |
| } |
| |
| /// Creates an empty `PtrWeakKeyHashMap` with the given capacity and hasher. |
| /// |
| /// *O*(*n*) time |
| pub fn with_capacity_and_hasher(capacity: usize, hash_builder: S) -> Self { |
| PtrWeakKeyHashMap(base::WeakKeyHashMap::with_capacity_and_hasher(capacity, hash_builder)) |
| } |
| |
| /// Returns a reference to the map's `BuildHasher`. |
| /// |
| /// *O*(1) time |
| pub fn hasher(&self) -> &S { |
| self.0.hasher() |
| } |
| |
| /// Returns the number of elements the map can hold without reallocating. |
| /// |
| /// *O*(1) time |
| pub fn capacity(&self) -> usize { |
| self.0.capacity() |
| } |
| |
| /// Removes all mappings whose keys have expired. |
| /// |
| /// *O*(*n*) time |
| pub fn remove_expired(&mut self) { |
| self.0.remove_expired() |
| } |
| |
| /// Reserves room for additional elements. |
| /// |
| /// *O*(*n*) time |
| 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. |
| /// |
| /// *O*(*n*) time |
| pub fn shrink_to_fit(&mut self) { |
| self.0.shrink_to_fit() |
| } |
| |
| /// Returns an over-approximation of the number of elements. |
| /// |
| /// *O*(1) time |
| pub fn len(&self) -> usize { |
| self.0.len() |
| } |
| |
| /// Is the map known to be empty? |
| /// |
| /// This could answer `false` for an empty map whose keys have |
| /// expired but have yet to be collected. |
| /// |
| /// *O*(1) time |
| pub fn is_empty(&self) -> bool { |
| self.len() == 0 |
| } |
| |
| /// The proportion of buckets that are used. |
| /// |
| /// This is an over-approximation because of expired keys. |
| /// |
| /// *O*(1) time |
| pub fn load_factor(&self) -> f32 { |
| self.0.load_factor() |
| } |
| |
| /// Gets the requested entry. |
| /// |
| /// expected *O*(1) time; worst-case *O*(*p*) time |
| pub fn entry(&mut self, key: K::Strong) -> Entry<ByPtr<K>, V> { |
| self.0.entry(key) |
| } |
| |
| /// Removes all associations from the map. |
| /// |
| /// *O*(*n*) time |
| pub fn clear(&mut self) { |
| self.0.clear() |
| } |
| |
| /// Returns a reference to the value corresponding to the key. |
| /// |
| /// expected *O*(1) time; worst-case *O*(*p*) time |
| pub fn get(&self, key: &K::Strong) -> Option<&V> { |
| self.0.get(&(key.deref() as *const _)) |
| } |
| |
| /// Returns true if the map contains the specified key. |
| /// |
| /// expected *O*(1) time; worst-case *O*(*p*) time |
| pub fn contains_key(&self, key:&K::Strong) -> bool { |
| self.0.contains_key(&(key.deref() as *const _)) |
| } |
| |
| /// Returns a mutable reference to the value corresponding to the key. |
| /// |
| /// expected *O*(1) time; worst-case *O*(*p*) time |
| pub fn get_mut(&mut self, key: &K::Strong) -> Option<&mut V> { |
| self.0.get_mut(&(key.deref() as *const _)) |
| } |
| |
| /// Unconditionally inserts the value, returning the old value if already present. Does not |
| /// replace the key. |
| /// |
| /// expected *O*(1) time; worst-case *O*(*p*) time |
| pub fn insert(&mut self, key: K::Strong, value: V) -> Option<V> { |
| self.0.insert(key, value) |
| } |
| |
| /// Removes the entry with the given key, if it exists, and returns the value. |
| /// |
| /// expected *O*(1) time; worst-case *O*(*p*) time |
| pub fn remove(&mut self, key: &K::Strong) -> Option<V> { |
| self.0.remove(&(key.deref() as *const _)) |
| } |
| |
| /// Removes all mappings not satisfying the given predicate. |
| /// |
| /// Also removes any expired mappings. |
| /// |
| /// *O*(*n*) time |
| pub fn retain<F>(&mut self, f: F) |
| where F: FnMut(K::Strong, &mut V) -> 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. |
| /// |
| /// expected *O*(*n*) time; worst-case *O*(*nq*) time (where *n* is |
| /// `self.capacity()` and *q* is the length of the probe sequences |
| /// in `other`) |
| pub fn submap_with<F, S1, V1>(&self, other: &PtrWeakKeyHashMap<K, V1, S1>, value_equal: F) -> bool |
| where F: FnMut(&V, &V1) -> bool, |
| S1: BuildHasher |
| { |
| self.0.is_submap_with(&other.0, value_equal) |
| } |
| |
| /// Is self a submap of other? |
| /// |
| /// expected *O*(*n*) time; worst-case *O*(*nq*) time (where *n* is |
| /// `self.capacity()` and *q* is the length of the probe sequences |
| /// in `other`) |
| pub fn is_submap<V1, S1>(&self, other: &PtrWeakKeyHashMap<K, V1, S1>) -> bool |
| where V: PartialEq<V1>, |
| S1: BuildHasher |
| { |
| self.0.is_submap(&other.0) |
| } |
| |
| /// Are the keys of self a subset of the keys of other? |
| /// |
| /// expected *O*(*n*) time; worst-case *O*(*nq*) time (where *n* is |
| /// `self.capacity()` and *q* is the length of the probe sequences |
| /// in `other`) |
| pub fn domain_is_subset<V1, S1>(&self, other: &PtrWeakKeyHashMap<K, V1, S1>) -> bool |
| where S1: BuildHasher |
| { |
| self.0.domain_is_subset(&other.0) |
| } |
| } |
| |
| impl<K: WeakElement, V, S> PtrWeakKeyHashMap<K, V, S> |
| where K::Strong: Deref |
| { |
| /// Gets an iterator over the keys and values. |
| /// |
| /// *O*(1) time |
| pub fn iter(&self) -> Iter<ByPtr<K>, V> { |
| self.0.iter() |
| } |
| |
| /// Gets an iterator over the keys. |
| /// |
| /// *O*(1) time |
| pub fn keys(&self) -> Keys<ByPtr<K>, V> { |
| self.0.keys() |
| } |
| |
| /// Gets an iterator over the values. |
| /// |
| /// *O*(1) time |
| pub fn values(&self) -> Values<ByPtr<K>, V> { |
| self.0.values() |
| } |
| |
| /// Gets an iterator over the keys and mutable values. |
| /// |
| /// *O*(1) time |
| pub fn iter_mut(&mut self) -> IterMut<ByPtr<K>, V> { |
| self.0.iter_mut() |
| } |
| |
| /// Gets an iterator over the mutable values. |
| /// |
| /// *O*(1) time |
| pub fn values_mut(&mut self) -> ValuesMut<ByPtr<K>, V> { |
| self.0.values_mut() |
| } |
| |
| /// Gets a draining iterator, which removes all the values but retains the storage. |
| /// |
| /// *O*(1) time (and *O*(*n*) time to dispose of the result) |
| pub fn drain(&mut self) -> Drain<ByPtr<K>, V> { |
| self.0.drain() |
| } |
| } |
| |
| impl<K, V, V1, S, S1> PartialEq<PtrWeakKeyHashMap<K, V1, S1>> |
| for PtrWeakKeyHashMap<K, V, S> |
| where K: WeakElement, |
| K::Strong: Deref, |
| V: PartialEq<V1>, |
| S: BuildHasher, |
| S1: BuildHasher |
| { |
| fn eq(&self, other: &PtrWeakKeyHashMap<K, V1, S1>) -> bool { |
| self.0 == other.0 |
| } |
| } |
| |
| impl<K: WeakElement, V: Eq, S: BuildHasher> Eq for PtrWeakKeyHashMap<K, V, S> |
| where K::Strong: Deref |
| { } |
| |
| impl<K: WeakElement, V, S: BuildHasher + Default> Default for PtrWeakKeyHashMap<K, V, S> |
| where K::Strong: Deref |
| { |
| fn default() -> Self { |
| PtrWeakKeyHashMap(base::WeakKeyHashMap::<ByPtr<K>, V, S>::default()) |
| } |
| } |
| |
| impl<'a, K, V, S> Index<&'a K::Strong> for PtrWeakKeyHashMap<K, V, S> |
| where K: WeakElement, |
| K::Strong: Deref, |
| S: BuildHasher |
| { |
| type Output = V; |
| |
| fn index(&self, index: &'a K::Strong) -> &Self::Output { |
| self.0.index(&(index.deref() as *const _)) |
| } |
| } |
| |
| impl<'a, K, V, S> IndexMut<&'a K::Strong> for PtrWeakKeyHashMap<K, V, S> |
| where |
| K: WeakElement, |
| K::Strong: Deref, |
| S: BuildHasher |
| { |
| fn index_mut(&mut self, index: &'a K::Strong) -> &mut Self::Output { |
| self.0.index_mut(&(index.deref() as *const _)) |
| } |
| } |
| |
| impl<K, V, S> FromIterator<(K::Strong, V)> for PtrWeakKeyHashMap<K, V, S> |
| where K: WeakElement, |
| K::Strong: Deref, |
| S: BuildHasher + Default |
| { |
| fn from_iter<T: IntoIterator<Item=(K::Strong, V)>>(iter: T) -> Self { |
| PtrWeakKeyHashMap(base::WeakKeyHashMap::<ByPtr<K>, V, S>::from_iter(iter)) |
| } |
| } |
| |
| impl<K, V, S> Extend<(K::Strong, V)> for PtrWeakKeyHashMap<K, V, S> |
| where K: WeakElement, |
| K::Strong: Deref, |
| S: BuildHasher |
| { |
| fn extend<T: IntoIterator<Item=(K::Strong, V)>>(&mut self, iter: T) { |
| self.0.extend(iter) |
| } |
| } |
| |
| impl<'a, K, V, S> Extend<(&'a K::Strong, &'a V)> for PtrWeakKeyHashMap<K, V, S> |
| where K: 'a + WeakElement, |
| K::Strong: Clone + Deref, |
| V: 'a + Clone, |
| S: BuildHasher |
| { |
| fn extend<T: IntoIterator<Item=(&'a K::Strong, &'a V)>>(&mut self, iter: T) { |
| self.0.extend(iter) |
| } |
| } |
| |
| impl<K, V: Debug, S> Debug for PtrWeakKeyHashMap<K, V, S> |
| where K: WeakElement, |
| K::Strong: Debug |
| { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| self.0.fmt(f) |
| } |
| } |
| |
| impl<K: WeakElement, V, S> IntoIterator for PtrWeakKeyHashMap<K, V, S> { |
| type Item = (K::Strong, V); |
| type IntoIter = IntoIter<ByPtr<K>, V>; |
| |
| /// Creates an owning iterator from `self`. |
| /// |
| /// *O*(1) time (and *O*(*n*) time to dispose of the result) |
| fn into_iter(self) -> Self::IntoIter { |
| self.0.into_iter() |
| } |
| } |
| |
| impl<'a, K: WeakElement, V, S> IntoIterator for &'a PtrWeakKeyHashMap<K, V, S> { |
| type Item = (K::Strong, &'a V); |
| type IntoIter = Iter<'a, ByPtr<K>, V>; |
| |
| /// Creates a borrowing iterator from `self`. |
| /// |
| /// *O*(1) time |
| fn into_iter(self) -> Self::IntoIter { |
| (&self.0).into_iter() |
| } |
| } |
| |
| impl<'a, K: WeakElement, V, S> IntoIterator for &'a mut PtrWeakKeyHashMap<K, V, S> { |
| type Item = (K::Strong, &'a mut V); |
| type IntoIter = IterMut<'a, ByPtr<K>, V>; |
| |
| /// Creates a borrowing iterator from `self`. |
| /// |
| /// *O*(1) time |
| fn into_iter(self) -> Self::IntoIter { |
| (&mut self.0).into_iter() |
| } |
| } |
| |
| #[cfg(test)] |
| mod test { |
| use crate::compat::{ |
| eprintln, |
| rc::{Rc, Weak}, |
| Vec, |
| }; |
| use super::{Entry, PtrWeakKeyHashMap}; |
| |
| // fn show_me(weakmap: &PtrWeakKeyHashMap<Weak<u32>, 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>> = Vec::new(); |
| |
| for i in 0 .. 200 { |
| rcs.push(Rc::new(i)); |
| } |
| |
| let mut weakmap: PtrWeakKeyHashMap<Weak<u32>, f32> = PtrWeakKeyHashMap::new(); |
| |
| for item in rcs.iter().cloned() { |
| let f = *item as f32 + 0.1; |
| weakmap.insert(item, f); |
| } |
| |
| let mut count = 0; |
| |
| for item in &rcs { |
| assert!(weakmap.contains_key(item)); |
| |
| match weakmap.entry(Rc::clone(item)) { |
| Entry::Occupied(_) => count += 1, |
| Entry::Vacant(_) => eprintln!("PointerWeakKeyHashMap: missing: {}", *item), |
| } |
| } |
| |
| assert_eq!( count, rcs.len() ); |
| } |
| } |