[][src]Struct linked_hash_map::LinkedHashMap

pub struct LinkedHashMap<K, V, S = RandomState> { /* fields omitted */ }

A linked hash map.

Methods

impl<K: Hash + Eq, V> LinkedHashMap<K, V>[src]

pub fn new() -> Self[src]

Creates a linked hash map.

pub fn with_capacity(capacity: usize) -> Self[src]

Creates an empty linked hash map with the given initial capacity.

impl<K: Hash + Eq, V, S: BuildHasher> LinkedHashMap<K, V, S>[src]

pub fn with_hasher(hash_builder: S) -> Self[src]

Creates an empty linked hash map with the given initial hash builder.

pub fn with_capacity_and_hasher(capacity: usize, hash_builder: S) -> Self[src]

Creates an empty linked hash map with the given initial capacity and hash builder.

pub fn reserve(&mut self, additional: usize)[src]

Reserves capacity for at least additional more elements to be inserted into the map. The map may reserve more space to avoid frequent allocations.

Panics

Panics if the new allocation size overflows usize.

pub fn shrink_to_fit(&mut self)[src]

Shrinks the capacity of the map 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 entry(&mut self, k: K) -> Entry<K, V, S>[src]

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

Examples

use linked_hash_map::LinkedHashMap;

let mut letters = LinkedHashMap::new();

for ch in "a short treatise on fungi".chars() {
    let counter = letters.entry(ch).or_insert(0);
    *counter += 1;
}

assert_eq!(letters[&'s'], 2);
assert_eq!(letters[&'t'], 3);
assert_eq!(letters[&'u'], 1);
assert_eq!(letters.get(&'y'), None);

pub fn entries(&mut self) -> Entries<K, V, S>[src]

Returns an iterator visiting all entries in insertion order. Iterator element type is OccupiedEntry<K, V, S>. Allows for removal as well as replacing the entry.

Examples

use linked_hash_map::LinkedHashMap;

let mut map = LinkedHashMap::new();
map.insert("a", 10);
map.insert("c", 30);
map.insert("b", 20);

{
    let mut iter = map.entries();
    let mut entry = iter.next().unwrap();
    assert_eq!(&"a", entry.key());
    *entry.get_mut() = 17;
}

assert_eq!(&17, map.get(&"a").unwrap());

pub fn insert(&mut self, k: K, v: V) -> Option<V>[src]

Inserts a key-value pair into the map. If the key already existed, the old value is returned.

Examples

use linked_hash_map::LinkedHashMap;
let mut map = LinkedHashMap::new();

map.insert(1, "a");
map.insert(2, "b");
assert_eq!(map[&1], "a");
assert_eq!(map[&2], "b");

pub fn contains_key<Q: ?Sized>(&self, k: &Q) -> bool where
    K: Borrow<Q>,
    Q: Eq + Hash
[src]

Checks if the map contains the given key.

pub fn get<Q: ?Sized>(&self, k: &Q) -> Option<&V> where
    K: Borrow<Q>,
    Q: Eq + Hash
[src]

Returns the value corresponding to the key in the map.

Examples

use linked_hash_map::LinkedHashMap;
let mut map = LinkedHashMap::new();

map.insert(1, "a");
map.insert(2, "b");
map.insert(2, "c");
map.insert(3, "d");

assert_eq!(map.get(&1), Some(&"a"));
assert_eq!(map.get(&2), Some(&"c"));

pub fn get_mut<Q: ?Sized>(&mut self, k: &Q) -> Option<&mut V> where
    K: Borrow<Q>,
    Q: Eq + Hash
[src]

Returns the mutable reference corresponding to the key in the map.

Examples

use linked_hash_map::LinkedHashMap;
let mut map = LinkedHashMap::new();

map.insert(1, "a");
map.insert(2, "b");

*map.get_mut(&1).unwrap() = "c";
assert_eq!(map.get(&1), Some(&"c"));

pub fn get_refresh<Q: ?Sized>(&mut self, k: &Q) -> Option<&mut V> where
    K: Borrow<Q>,
    Q: Eq + Hash
[src]

Returns the value corresponding to the key in the map.

If value is found, it is moved to the end of the list. This operation can be used in implemenation of LRU cache.

Examples

use linked_hash_map::LinkedHashMap;
let mut map = LinkedHashMap::new();

map.insert(1, "a");
map.insert(2, "b");
map.insert(3, "d");

assert_eq!(map.get_refresh(&2), Some(&mut "b"));

assert_eq!((&2, &"b"), map.iter().rev().next().unwrap());

pub fn remove<Q: ?Sized>(&mut self, k: &Q) -> Option<V> where
    K: Borrow<Q>,
    Q: Eq + Hash
[src]

Removes and returns the value corresponding to the key from the map.

Examples

use linked_hash_map::LinkedHashMap;
let mut map = LinkedHashMap::new();

map.insert(2, "a");

assert_eq!(map.remove(&1), None);
assert_eq!(map.remove(&2), Some("a"));
assert_eq!(map.remove(&2), None);
assert_eq!(map.len(), 0);

pub fn capacity(&self) -> usize[src]

Returns the maximum number of key-value pairs the map can hold without reallocating.

Examples

use linked_hash_map::LinkedHashMap;
let mut map: LinkedHashMap<i32, &str> = LinkedHashMap::new();
let capacity = map.capacity();

pub fn pop_front(&mut self) -> Option<(K, V)>[src]

Removes the first entry.

Can be used in implementation of LRU cache.

Examples

use linked_hash_map::LinkedHashMap;
let mut map = LinkedHashMap::new();
map.insert(1, 10);
map.insert(2, 20);
map.pop_front();
assert_eq!(map.get(&1), None);
assert_eq!(map.get(&2), Some(&20));

pub fn front(&self) -> Option<(&K, &V)>[src]

Gets the first entry.

Examples

use linked_hash_map::LinkedHashMap;
let mut map = LinkedHashMap::new();
map.insert(1, 10);
map.insert(2, 20);
assert_eq!(map.front(), Some((&1, &10)));

pub fn pop_back(&mut self) -> Option<(K, V)>[src]

Removes the last entry.

Examples

use linked_hash_map::LinkedHashMap;
let mut map = LinkedHashMap::new();
map.insert(1, 10);
map.insert(2, 20);
map.pop_back();
assert_eq!(map.get(&1), Some(&10));
assert_eq!(map.get(&2), None);

pub fn back(&mut self) -> Option<(&K, &V)>[src]

Gets the last entry.

Examples

use linked_hash_map::LinkedHashMap;
let mut map = LinkedHashMap::new();
map.insert(1, 10);
map.insert(2, 20);
assert_eq!(map.back(), Some((&2, &20)));

pub fn len(&self) -> usize[src]

Returns the number of key-value pairs in the map.

pub fn is_empty(&self) -> bool[src]

Returns whether the map is currently empty.

pub fn hasher(&self) -> &S[src]

Returns a reference to the map's hasher.

pub fn clear(&mut self)[src]

Clears the map of all key-value pairs.

pub fn iter(&self) -> Iter<K, V>[src]

Returns a double-ended iterator visiting all key-value pairs in order of insertion. Iterator element type is (&'a K, &'a V)

Examples

use linked_hash_map::LinkedHashMap;

let mut map = LinkedHashMap::new();
map.insert("a", 10);
map.insert("c", 30);
map.insert("b", 20);

let mut iter = map.iter();
assert_eq!((&"a", &10), iter.next().unwrap());
assert_eq!((&"c", &30), iter.next().unwrap());
assert_eq!((&"b", &20), iter.next().unwrap());
assert_eq!(None, iter.next());

pub fn iter_mut(&mut self) -> IterMut<K, V>[src]

Returns a double-ended iterator visiting all key-value pairs in order of insertion. Iterator element type is (&'a K, &'a mut V)

Examples

use linked_hash_map::LinkedHashMap;

let mut map = LinkedHashMap::new();
map.insert("a", 10);
map.insert("c", 30);
map.insert("b", 20);

{
    let mut iter = map.iter_mut();
    let mut entry = iter.next().unwrap();
    assert_eq!(&"a", entry.0);
    *entry.1 = 17;
}

assert_eq!(&17, map.get(&"a").unwrap());

pub fn keys(&self) -> Keys<K, V>[src]

Returns a double-ended iterator visiting all key in order of insertion.

Examples

use linked_hash_map::LinkedHashMap;

let mut map = LinkedHashMap::new();
map.insert('a', 10);
map.insert('c', 30);
map.insert('b', 20);

let mut keys = map.keys();
assert_eq!(&'a', keys.next().unwrap());
assert_eq!(&'c', keys.next().unwrap());
assert_eq!(&'b', keys.next().unwrap());
assert_eq!(None, keys.next());

pub fn values(&self) -> Values<K, V>[src]

Returns a double-ended iterator visiting all values in order of insertion.

Examples

use linked_hash_map::LinkedHashMap;

let mut map = LinkedHashMap::new();
map.insert('a', 10);
map.insert('c', 30);
map.insert('b', 20);

let mut values = map.values();
assert_eq!(&10, values.next().unwrap());
assert_eq!(&30, values.next().unwrap());
assert_eq!(&20, values.next().unwrap());
assert_eq!(None, values.next());

Trait Implementations

impl<K: Hash + Eq + Clone, V: Clone, S: BuildHasher + Clone> Clone for LinkedHashMap<K, V, S>[src]

impl<A: Debug + Hash + Eq, B: Debug, S: BuildHasher> Debug for LinkedHashMap<A, B, S>[src]

fn fmt(&self, f: &mut Formatter) -> Result[src]

Returns a string that lists the key-value pairs in insertion order.

impl<K: Hash + Eq, V, S: BuildHasher + Default> Default for LinkedHashMap<K, V, S>[src]

impl<K, V, S> Drop for LinkedHashMap<K, V, S>[src]

impl<K: Hash + Eq, V: Eq, S: BuildHasher> Eq for LinkedHashMap<K, V, S>[src]

impl<'a, K, V, S> Extend<(&'a K, &'a V)> for LinkedHashMap<K, V, S> where
    K: 'a + Hash + Eq + Copy,
    V: 'a + Copy,
    S: BuildHasher
[src]

impl<K: Hash + Eq, V, S: BuildHasher> Extend<(K, V)> for LinkedHashMap<K, V, S>[src]

impl<K: Hash + Eq, V, S: BuildHasher + Default> FromIterator<(K, V)> for LinkedHashMap<K, V, S>[src]

impl<K: Hash + Eq, V: Hash, S: BuildHasher> Hash for LinkedHashMap<K, V, S>[src]

impl<'a, K, V, S, Q: ?Sized> Index<&'a Q> for LinkedHashMap<K, V, S> where
    K: Hash + Eq + Borrow<Q>,
    S: BuildHasher,
    Q: Eq + Hash
[src]

type Output = V

The returned type after indexing.

impl<'a, K, V, S, Q: ?Sized> IndexMut<&'a Q> for LinkedHashMap<K, V, S> where
    K: Hash + Eq + Borrow<Q>,
    S: BuildHasher,
    Q: Eq + Hash
[src]

impl<'a, K: Hash + Eq, V, S: BuildHasher> IntoIterator for &'a LinkedHashMap<K, V, S>[src]

type Item = (&'a K, &'a V)

The type of the elements being iterated over.

type IntoIter = Iter<'a, K, V>

Which kind of iterator are we turning this into?

impl<'a, K: Hash + Eq, V, S: BuildHasher> IntoIterator for &'a mut LinkedHashMap<K, V, S>[src]

type Item = (&'a K, &'a mut V)

The type of the elements being iterated over.

type IntoIter = IterMut<'a, K, V>

Which kind of iterator are we turning this into?

impl<K: Hash + Eq, V, S: BuildHasher> IntoIterator for LinkedHashMap<K, V, S>[src]

type Item = (K, V)

The type of the elements being iterated over.

type IntoIter = IntoIter<K, V>

Which kind of iterator are we turning this into?

impl<K: Hash + Eq + Ord, V: Ord, S: BuildHasher> Ord for LinkedHashMap<K, V, S>[src]

impl<K: Hash + Eq, V: PartialEq, S: BuildHasher> PartialEq<LinkedHashMap<K, V, S>> for LinkedHashMap<K, V, S>[src]

impl<K: Hash + Eq + PartialOrd, V: PartialOrd, S: BuildHasher> PartialOrd<LinkedHashMap<K, V, S>> for LinkedHashMap<K, V, S>[src]

impl<K: Send, V: Send, S: Send> Send for LinkedHashMap<K, V, S>[src]

impl<K: Sync, V: Sync, S: Sync> Sync for LinkedHashMap<K, V, S>[src]

Auto Trait Implementations

impl<K, V, S> RefUnwindSafe for LinkedHashMap<K, V, S> where
    K: RefUnwindSafe,
    S: RefUnwindSafe,
    V: RefUnwindSafe

impl<K, V, S> Unpin for LinkedHashMap<K, V, S> where
    S: Unpin

impl<K, V, S> UnwindSafe for LinkedHashMap<K, V, S> where
    K: RefUnwindSafe,
    S: UnwindSafe,
    V: RefUnwindSafe

Blanket Implementations

impl<T> Any for T where
    T: 'static + ?Sized
[src]

impl<T> Borrow<T> for T where
    T: ?Sized
[src]

impl<T> BorrowMut<T> for T where
    T: ?Sized
[src]

impl<T> From<T> for T[src]

impl<T, U> Into<U> for T where
    U: From<T>, 
[src]

impl<I> IntoIterator for I where
    I: Iterator
[src]

type Item = <I as Iterator>::Item

The type of the elements being iterated over.

type IntoIter = I

Which kind of iterator are we turning this into?

impl<T> ToOwned for T where
    T: Clone
[src]

type Owned = T

The resulting type after obtaining ownership.

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.