[][src]Struct heapless::IndexMap

pub struct IndexMap<K, V, N, S> where
    K: Eq + Hash,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
{ /* fields omitted */ }

Fixed capacity IndexMap

Note that the capacity of the IndexMap must be a power of 2.

Examples

use heapless::FnvIndexMap;
use heapless::consts::*;

// A hash map with a capacity of 16 key-value pairs allocated on the stack
let mut book_reviews = FnvIndexMap::<_, _, U16>::new();

// review some books.
book_reviews.insert("Adventures of Huckleberry Finn",    "My favorite book.").unwrap();
book_reviews.insert("Grimms' Fairy Tales",               "Masterpiece.").unwrap();
book_reviews.insert("Pride and Prejudice",               "Very enjoyable.").unwrap();
book_reviews.insert("The Adventures of Sherlock Holmes", "Eye lyked it alot.").unwrap();

// check for a specific one.
if !book_reviews.contains_key("Les Misérables") {
    println!("We've got {} reviews, but Les Misérables ain't one.",
             book_reviews.len());
}

// oops, this review has a lot of spelling mistakes, let's delete it.
book_reviews.remove("The Adventures of Sherlock Holmes");

// look up the values associated with some keys.
let to_find = ["Pride and Prejudice", "Alice's Adventure in Wonderland"];
for book in &to_find {
    match book_reviews.get(book) {
        Some(review) => println!("{}: {}", book, review),
        None => println!("{} is unreviewed.", book)
    }
}

// iterate over everything.
for (book, review) in &book_reviews {
    println!("{}: \"{}\"", book, review);
}

Methods

impl<K, V, N, S> IndexMap<K, V, N, BuildHasherDefault<S>> where
    K: Eq + Hash,
    S: Default + Hasher,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>> + PowerOfTwo
[src]

pub fn new() -> Self[src]

Creates an empty IndexMap.

NOTE This constructor will become a const fn in the future

impl<K, V, N, S> IndexMap<K, V, N, S> where
    K: Eq + Hash,
    S: BuildHasher,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[src]

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

Returns the number of elements the map can hold

pub fn keys(&self) -> impl Iterator<Item = &K>[src]

Return an iterator over the keys of the map, in their order

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U16>::new();
map.insert("a", 1).unwrap();
map.insert("b", 2).unwrap();
map.insert("c", 3).unwrap();

for key in map.keys() {
    println!("{}", key);
}

pub fn values(&self) -> impl Iterator<Item = &V>[src]

Return an iterator over the values of the map, in their order

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U16>::new();
map.insert("a", 1).unwrap();
map.insert("b", 2).unwrap();
map.insert("c", 3).unwrap();

for val in map.values() {
    println!("{}", val);
}

pub fn values_mut(&mut self) -> impl Iterator<Item = &mut V>[src]

Return an iterator over mutable references to the the values of the map, in their order

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U16>::new();
map.insert("a", 1).unwrap();
map.insert("b", 2).unwrap();
map.insert("c", 3).unwrap();

for val in map.values_mut() {
    *val += 10;
}

for val in map.values() {
    println!("{}", val);
}

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

Return an iterator over the key-value pairs of the map, in their order

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U16>::new();
map.insert("a", 1).unwrap();
map.insert("b", 2).unwrap();
map.insert("c", 3).unwrap();

for (key, val) in map.iter() {
    println!("key: {} val: {}", key, val);
}

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

Return an iterator over the key-value pairs of the map, in their order

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U16>::new();
map.insert("a", 1).unwrap();
map.insert("b", 2).unwrap();
map.insert("c", 3).unwrap();

for (_, val) in map.iter_mut() {
    *val = 2;
}

for (key, val) in &map {
    println!("key: {} val: {}", key, val);
}

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

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

Computes in O(1) time.

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut a = FnvIndexMap::<_, _, U16>::new();
assert_eq!(a.len(), 0);
a.insert(1, "a").unwrap();
assert_eq!(a.len(), 1);

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

Returns true if the map contains no elements.

Computes in O(1) time.

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut a = FnvIndexMap::<_, _, U16>::new();
assert!(a.is_empty());
a.insert(1, "a");
assert!(!a.is_empty());

pub fn clear(&mut self)[src]

Remove all key-value pairs in the map, while preserving its capacity.

Computes in O(n) time.

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut a = FnvIndexMap::<_, _, U16>::new();
a.insert(1, "a");
a.clear();
assert!(a.is_empty());

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

Returns a reference to the value corresponding to the key.

The key may be any borrowed form of the map's key type, but Hash and Eq on the borrowed form must match those for the key type.

Computes in O(1) time (average).

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U16>::new();
map.insert(1, "a").unwrap();
assert_eq!(map.get(&1), Some(&"a"));
assert_eq!(map.get(&2), None);

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

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

The key may be any borrowed form of the map's key type, but Hash and Eq on the borrowed form must match those for the key type.

Computes in O(1) time (average).

Examples

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U8>::new();
map.insert(1, "a").unwrap();
assert_eq!(map.contains_key(&1), true);
assert_eq!(map.contains_key(&2), false);

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

Returns a mutable reference to the value corresponding to the key.

The key may be any borrowed form of the map's key type, but Hash and Eq on the borrowed form must match those for the key type.

Computes in O(1) time (average).

Examples

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U8>::new();
map.insert(1, "a").unwrap();
if let Some(x) = map.get_mut(&1) {
    *x = "b";
}
assert_eq!(map[&1], "b");

pub fn insert(&mut self, key: K, value: V) -> Result<Option<V>, (K, V)>[src]

Inserts a key-value pair into the map.

If an equivalent key already exists in the map: the key remains and retains in its place in the order, its corresponding value is updated with value and the older value is returned inside Some(_).

If no equivalent key existed in the map: the new key-value pair is inserted, last in order, and None is returned.

Computes in O(1) time (average).

See also entry if you you want to insert or modify or if you need to get the index of the corresponding key-value pair.

Examples

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U8>::new();
assert_eq!(map.insert(37, "a"), Ok(None));
assert_eq!(map.is_empty(), false);

map.insert(37, "b");
assert_eq!(map.insert(37, "c"), Ok(Some("b")));
assert_eq!(map[&37], "c");

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

Same as swap_remove

Computes in O(1) time (average).

Examples

use heapless::FnvIndexMap;
use heapless::consts::*;

let mut map = FnvIndexMap::<_, _, U8>::new();
map.insert(1, "a").unwrap();
assert_eq!(map.remove(&1), Some("a"));
assert_eq!(map.remove(&1), None);

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

Remove the key-value pair equivalent to key and return its value.

Like Vec::swap_remove, the pair is removed by swapping it with the last element of the map and popping it off. This perturbs the postion of what used to be the last element!

Return None if key is not in map.

Computes in O(1) time (average).

Trait Implementations

impl<K, V, N, S> Debug for IndexMap<K, V, N, S> where
    K: Eq + Hash + Debug,
    V: Debug,
    S: BuildHasher,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[src]

impl<'a, K, Q: ?Sized, V, N, S> Index<&'a Q> for IndexMap<K, V, N, S> where
    K: Eq + Hash + Borrow<Q>,
    Q: Eq + Hash,
    S: BuildHasher,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[src]

type Output = V

The returned type after indexing.

impl<'a, K, Q: ?Sized, V, N, S> IndexMut<&'a Q> for IndexMap<K, V, N, S> where
    K: Eq + Hash + Borrow<Q>,
    Q: Eq + Hash,
    S: BuildHasher,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[src]

impl<K, V, N, S> FromIterator<(K, V)> for IndexMap<K, V, N, S> where
    K: Eq + Hash,
    S: BuildHasher + Default,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[src]

impl<'a, K, V, N, S> IntoIterator for &'a IndexMap<K, V, N, S> where
    K: Eq + Hash,
    S: BuildHasher,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[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, V, N, S> IntoIterator for &'a mut IndexMap<K, V, N, S> where
    K: Eq + Hash,
    S: BuildHasher,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[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, V, N, S> Extend<(K, V)> for IndexMap<K, V, N, S> where
    K: Eq + Hash,
    S: BuildHasher,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[src]

impl<'a, K, V, N, S> Extend<(&'a K, &'a V)> for IndexMap<K, V, N, S> where
    K: Eq + Hash + Copy,
    V: Copy,
    S: BuildHasher,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[src]

impl<K, V, N, S> Clone for IndexMap<K, V, N, S> where
    K: Eq + Hash + Clone,
    V: Clone,
    S: Clone,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[src]

fn clone_from(&mut self, source: &Self)
1.0.0
[src]

Performs copy-assignment from source. Read more

impl<K, V, N, S> Default for IndexMap<K, V, N, S> where
    K: Eq + Hash,
    S: BuildHasher + Default,
    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>, 
[src]

Auto Trait Implementations

impl<K, V, N, S> Send for IndexMap<K, V, N, S> where
    K: Send,
    S: Send,
    V: Send

impl<K, V, N, S> Sync for IndexMap<K, V, N, S> where
    K: Sync,
    S: Sync,
    V: Sync

Blanket Implementations

impl<T> From for T[src]

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

type Error = Infallible

The type returned in the event of a conversion error.

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

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

The type returned in the event of a conversion error.

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

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

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

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

impl<T> Same for T[src]

type Output = T

Should always be Self