Struct enum_collections::EnumTable

pub struct EnumTable<'a, K, V>where
    K: Enumerated,
    V: Default,{ /* private fields */ }

A key-value table optimized for Enums used as keys. Initialized with V’s Default values.

use enum_collections::{EnumTable, Enumerated};
#[derive(Enumerated)]
enum Letter {
    A,
    B,
}

let mut map: EnumTable<Letter, u8> = EnumTable::new();
map[Letter::A] = 42;
assert_eq!(42u8, map[Letter::A]);
assert_eq!(u8::default(), map[Letter::B]);

Using get and insert functions.

use enum_collections::{enum_collections, EnumTable, Enumerated};
#[derive(Enumerated)]
enum Letter {
    A,
    B,
}

let mut map: EnumTable<Letter, u8> = EnumTable::new();
map.insert(Letter::A, 42);
assert_eq!(&42u8, map.get(Letter::A));
assert_eq!(&u8::default(), map.get(Letter::B));

Implementations

impl<'a, K, V> EnumTable<'a, K, V>where
    K: Enumerated,
    V: Default,

pub fn new() -> Self

Creates a new EnumTable, with pre-allocated space for all keys of the enum K. With the underlying array righsized, no resizing is further required. All values are initialized with V’s Default value.

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

Obtain a value for given key, always returning a value V, as the EnumTable is pre-initialized with defaults.

Args

• key - Instance of K, used to look up the corresponding value.

pub fn insert(&mut self, key: K, value: V)

Stores given value under the provided key. Overrides any existing corresponding value.

Args

• key - The instance of K the value inserted can be looked up for.
• values - Value to bind to K.

pub fn reset(&mut self, key: K)

Resets value of type V corresponding to key to its default by calling its Default trait implementation.

Args

• key - The instance of K pointing at the slot to reset to default.

Trait Implementations

impl<'a, K, V> Default for EnumTable<'a, K, V>where
    K: Enumerated,
    V: Default,

fn default() -> Self

Constructs a new instance, capable of holding all values of key K without further resizing.

impl<'a, K, V> Index<K> for EnumTable<'a, K, V>where
    K: Enumerated,
    V: Default,

type Output = V

The returned type after indexing.

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

Performs the indexing (container[index]) operation.

impl<'a, K, V> IndexMut<K> for EnumTable<'a, K, V>where
    K: Enumerated,
    V: Default,

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

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