Struct slabby::Slab

pub struct Slab<T, K: Key> { /* private fields */ }

A Slab which can hold some number of elements, depending on the chosen K.

Examples

let mut slab = slabby::Slab32::new();
unsafe {
    let key1 = slab.insert(1);
    let key2 = slab.insert(2);
    let key3 = slab.insert(3);

    assert_eq!(slab.get(key1), &1);
    assert_eq!(slab.get(key2), &2);
    assert_eq!(slab.get(key3), &3);

    assert_eq!(slab.remove(key2), 2);
    assert_eq!(slab.remove(key1), 1);

    assert_eq!(slab.get(key3), &3);

    slab.insert(4);
    let key5 = slab.insert(5);
    slab.insert(6);

    assert_eq!(slab.len(), 4);

    *slab.get_mut(key5) += 1;
    assert_eq!(slab.remove(key5), 6);

    assert_eq!(slab.len(), 3);
}

Implementations

impl<T, K: Key> Slab<T, K>

pub fn new() -> Self

Create a new Slab. No allocations will occur until the first Slab::insert.

pub unsafe fn insert(&mut self, val: T) -> K

Safety

The number of occupied slots must be lower than the maximum value of K. This is trivially true if the maximum value of K is greater or equal to that of usize.

pub unsafe fn remove(&mut self, key: K) -> T

Remove a previously inserted element from the Slab. Returns the contained T.

Safety

The provided key must have been obtained from this instance of Slab and not removed between the insertion and this call.

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

Safety

The provided key must have been obtained from this instance of Slab and not removed between the insertion and this call.

pub unsafe fn get_mut(&mut self, key: K) -> &mut T

Safety

The provided key must have been obtained from this instance of Slab and not removed between the insertion and this call.

pub fn next(&self) -> K

Get the key of the next element to be inserted into this Slab.

pub fn len(&self) -> K

Get the number of elements contained within this Slab.

Trait Implementations

impl<T, K: Key> Debug for Slab<T, K>

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

Formats the value using the given formatter.

impl<T, K: Key> Default for Slab<T, K>

fn default() -> Self

Returns the “default value” for a type.