Struct compactmap::CompactMap

pub struct CompactMap<V> { /* fields omitted */ }

A map that chooses small integer keys for you. You store something into this map and then access it by ID returned by it. For small V entries are expected to take 16 bytes.

Example:

use compactmap::CompactMap;

let mut mymap : CompactMap<String> = CompactMap::new();
let id_qwerty = mymap.insert("qwerty".to_string());
let id_qwertz = mymap.insert("qwertz".to_string());
assert_eq!(mymap[id_qwerty], "qwerty");
for (id, val) in mymap {
    println!("{}:{}", id, val);
}

Methods

impl<V> CompactMap<V>

fn new() -> CompactMap<V>

Creates an empty CompactMap.

Examples

use compactmap::CompactMap;
let mut map: CompactMap<String> = CompactMap::new();

fn with_capacity(capacity: usize) -> Self

Creates an empty CompactMap with space for at least capacity elements before resizing.

Examples

use compactmap::CompactMap;
let mut map: CompactMap<String> = CompactMap::with_capacity(10);

fn capacity(&self) -> usize

Returns capacity of the underlying vector.

fn reserve(&mut self, len: usize)

Reserves capacity for CompactMap's underlying vector. If you just cleared M elements from the map and want to insert N more elements, you'll probably need to reserve N-M elements.

fn reserve_exact(&mut self, len: usize)

Reserves capacity for CompactMap's underlying vector. If you just cleared M elements from the map and want to insert N more elements, you'll probably need to reserve N-M elements.

fn is_empty_slow(&self) -> bool

Iterating the map to check if it is empty. O(n) where n is historical maximum element count.

fn insert(&mut self, v: V) -> usize

Inserts a value into the map. The map generates and returns ID of the inserted element.

Examples

use compactmap::CompactMap;

let mut map = CompactMap::new();
assert_eq!(map.is_empty_slow(), true);
assert_eq!(map.insert(37), 0);
assert_eq!(map.is_empty_slow(), false);

assert_eq!(map.insert(37), 1);
assert_eq!(map.insert(37), 2);
assert_eq!(map.insert(44), 3);
assert_eq!(map.len_slow(), 4);

fn remove(&mut self, i: usize) -> Option<V>

Removes a key from the map, returning the value at the key if the key was previously in the map. ``` use compactmap::CompactMap;

let mut map = CompactMap::new(); let id = map.insert("a"); assert_eq!(map.remove(id), Some("a")); assert_eq!(map.remove(123), None); ```

fn get(&self, i: usize) -> Option<&V>

Returns a reference to the value corresponding to the key.

fn get_mut(&mut self, i: usize) -> Option<&mut V>

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

fn iter<'a>(&'a self) -> Iter<'a, V>

Returns an iterator visiting all key-value pairs in unspecified order. The iterator's element type is (usize, &'r V).

Examples

use compactmap::CompactMap;

let mut map = CompactMap::new();
map.insert("a");
map.insert("c");
map.insert("b");

// Print `1: a`, `2: b` and `3: c`.
for (key, value) in map.iter() {
    println!("{}: {}", key, value);
}

fn iter_mut<'a>(&'a mut self) -> IterMut<'a, V>

Returns an iterator visiting all key-value pairs in unspecified order, with mutable references to the values. The iterator's element type is (usize, &'r mut V)

fn into_iter(self) -> IntoIter<V>

Returns an iterator visiting all key-value pairs in unspecified order, the keys, consuming the original CompactMap. The iterator's element type is (usize, V).

fn len_slow(&self) -> usize

Iterates the map to get number of elements. O(n) where n is historical maximum element count.

Trait Implementations

impl<V: Clone> Clone for CompactMap<V>

fn clone(&self) -> CompactMap<V>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<V> Default for CompactMap<V>

fn default() -> CompactMap<V>

Returns the "default value" for a type.

impl<V> Hash for CompactMap<V> where
    V: Hash, 

fn hash<H>(&self, state: &mut H) where
    H: Hasher, 

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl<V: PartialEq> PartialEq for CompactMap<V>

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<V: Eq> Eq for CompactMap<V>

impl<V> PartialOrd<CompactMap<V>> for CompactMap<V> where
    V: PartialOrd<V>, 

fn partial_cmp(&self, other: &CompactMap<V>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<V> Ord for CompactMap<V> where
    V: Ord, 

fn cmp(&self, other: &CompactMap<V>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

impl<V> FromIterator<V> for CompactMap<V>

fn from_iter<I>(iter: I) -> CompactMap<V> where
    I: IntoIterator<Item = V>, 

Creates a value from an iterator.

impl<'a, V> FromIterator<&'a V> for CompactMap<V> where
    V: Copy, 

fn from_iter<I>(iter: I) -> CompactMap<V> where
    I: IntoIterator<Item = &'a V>, 

Creates a value from an iterator.

impl<V> Extend<V> for CompactMap<V>

fn extend<I>(&mut self, iter: I) where
    I: IntoIterator<Item = V>, 

Extends a collection with the contents of an iterator.

impl<'a, V> Extend<&'a V> for CompactMap<V> where
    V: Copy, 

fn extend<I>(&mut self, iter: I) where
    I: IntoIterator<Item = &'a V>, 

Extends a collection with the contents of an iterator.

impl<V> Index<usize> for CompactMap<V>

type Output = V

The returned type after indexing.

fn index(&self, i: usize) -> &V

Performs the indexing (container[index]) operation.

impl<'a, V> Index<&'a usize> for CompactMap<V>

type Output = V

The returned type after indexing.

fn index(&self, i: &usize) -> &V

Performs the indexing (container[index]) operation.

impl<V> IndexMut<usize> for CompactMap<V>

fn index_mut(&mut self, i: usize) -> &mut V

Performs the mutable indexing (container[index]) operation.

impl<'a, V> IndexMut<&'a usize> for CompactMap<V>

fn index_mut(&mut self, i: &usize) -> &mut V

Performs the mutable indexing (container[index]) operation.

impl<V: Debug> Debug for CompactMap<V>

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

Formats the value using the given formatter.

impl<'a, V> IntoIterator for &'a CompactMap<V>

type Item = (usize, &'a V)

The type of the elements being iterated over.

type IntoIter = Iter<'a, V>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Iter<'a, V>

Creates an iterator from a value.

impl<'a, V: 'a> IntoIterator for &'a mut CompactMap<V>

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

The type of the elements being iterated over.

type IntoIter = IterMut<'a, V>

Which kind of iterator are we turning this into?

fn into_iter(self) -> IterMut<'a, V>

Creates an iterator from a value.

impl<V> IntoIterator for CompactMap<V>

type Item = (usize, V)

The type of the elements being iterated over.

type IntoIter = IntoIter<V>

Which kind of iterator are we turning this into?

fn into_iter(self) -> IntoIter<V>

Creates an iterator from a value.