Struct enum_map::EnumMap

pub struct EnumMap<K: Enum<V>, V> { /* fields omitted */ }

An enum mapping.

This internally uses an array which stores a value for each possible enum value. To work, it requires implementation of internal (private, although public due to macro limitations) trait which allows extracting information about an enum, which can be automatically generated using #[derive(Enum)] macro.

Additionally, bool and u8 automatically derives from Enum. While u8 is not technically an enum, it’s convenient to consider it like one. In particular, reverse-complement in benchmark game could be using u8 as an enum.

Examples

use enum_map::{enum_map, Enum, EnumMap};

#[derive(Enum)]
enum Example {
    A,
    B,
    C,
}

let mut map = EnumMap::default();
// new initializes map with default values
assert_eq!(map[Example::A], 0);
map[Example::A] = 3;
assert_eq!(map[Example::A], 3);

Implementations

impl<K: Enum<V>, V> EnumMap<K, V>

pub fn values(&self) -> Values<'_, V>

An iterator visiting all values. The iterator type is &V.

Examples

use enum_map::enum_map;

let map = enum_map! { false => 3, true => 4 };
let mut values = map.values();
assert_eq!(values.next(), Some(&3));
assert_eq!(values.next(), Some(&4));
assert_eq!(values.next(), None);

pub fn values_mut(&mut self) -> ValuesMut<'_, V>

An iterator visiting all values mutably. The iterator type is &mut V.

Examples

use enum_map::enum_map;

let mut map = enum_map! { _ => 2 };
for value in map.values_mut() {
    *value += 2;
}
assert_eq!(map[false], 4);
assert_eq!(map[true], 4);

impl<K: Enum<V>, V: Default> EnumMap<K, V>

pub fn clear(&mut self)

Clear enum map with default values.

Examples

use enum_map::{Enum, EnumMap};

#[derive(Enum)]
enum Example {
    A,
    B,
}

let mut enum_map = EnumMap::<_, String>::default();
enum_map[Example::B] = "foo".into();
enum_map.clear();
assert_eq!(enum_map[Example::A], "");
assert_eq!(enum_map[Example::B], "");

impl<K: Enum<V>, V> EnumMap<K, V>

pub fn from_array(array: K::Array) -> EnumMap<K, V>

Creates an enum map from array.

pub fn iter(&self) -> Iter<'_, K, V>

Returns an iterator over enum map.

pub fn iter_mut(&mut self) -> IterMut<'_, K, V>

Returns a mutable iterator over enum map.

pub fn len(&self) -> usize

Returns number of elements in enum map.

pub fn swap(&mut self, a: K, b: K)

Swaps two indexes.

Examples

use enum_map::enum_map;

let mut map = enum_map! { false => 0, true => 1 };
map.swap(false, true);
assert_eq!(map[false], 1);
assert_eq!(map[true], 0);

pub fn as_slice(&self) -> &[V]

Converts an enum map to a slice representing values.

pub fn as_mut_slice(&mut self) -> &mut [V]

Converts a mutable enum map to a mutable slice representing values.

Trait Implementations

impl<K: Enum<V>, V> Clone for EnumMap<K, V> where
    K::Array: Clone, 

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<K: Enum<V> + Debug, V: Debug> Debug for EnumMap<K, V>

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

Formats the value using the given formatter.

impl<K: Enum<V>, V: Default> Default for EnumMap<K, V>

fn default() -> Self

Returns the “default value” for a type.

impl<'a, K, V> Extend<(&'a K, &'a V)> for EnumMap<K, V> where
    K: Enum<V> + Copy,
    V: Copy, 

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

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬 This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬 This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<K: Enum<V>, V> Extend<(K, V)> for EnumMap<K, V>

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

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬 This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬 This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<K: Enum<V>, V: Hash> Hash for EnumMap<K, V>

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

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<K: Enum<V>, V> Index<K> for EnumMap<K, V>

type Output = V

The returned type after indexing.

fn index(&self, key: K) -> &V

Performs the indexing (container[index]) operation.

impl<K: Enum<V>, V> IndexMut<K> for EnumMap<K, V>

fn index_mut(&mut self, key: K) -> &mut V

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

impl<'a, K: Enum<V>, V> IntoIterator for &'a EnumMap<K, V>

type Item = (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?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<'a, K: Enum<V>, V> IntoIterator for &'a mut EnumMap<K, V>

type Item = (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?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<K: Enum<V>, V> IntoIterator for EnumMap<K, V>

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?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<K: Enum<V>, V: PartialEq> PartialEq<EnumMap<K, V>> for EnumMap<K, 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<K: Enum<V>, V> Copy for EnumMap<K, V> where
    K::Array: Copy, 

impl<K: Enum<V>, V: Eq> Eq for EnumMap<K, V>