Struct AllocVec

Source

pub struct AllocVec<T> { /* private fields */ }

Expand description

Simple wrapper for Vec that handles allocating / deallocating slots inside the vector, optimized for frequent indexing and frequent allocations / de-allocations.

The index obtained through allocation is guaranteed to remain the same and won’t be reused until deallocated

Implementations§

Source §

impl<T> AllocVec<T>

Source

pub const fn new() -> Self

Creates a new AllocVec backed by an empty Vec

Source

pub fn with_capacity(capacity: usize) -> Self

Creates a new AllocVec backed by a Vec with the given capacity

Source

pub fn get(&self, index: usize) -> Option<&T>

Returns an immutable reference to an element at the given position

§Arguments

index - The index of the element

§Returns

Some if the element is allocated at the index
None otherwise

Source

pub fn get_mut(&mut self, index: usize) -> Option<&mut T>

Returns a mutable reference to an element at the given position

§Arguments

index - The index of the element

§Returns

Some if the element is allocated at the index
None otherwise

Source

pub fn into_vec(self) -> Vec<T>

Constructs a new vector containing all the elements of this AllocVec that are allocated

Source

pub fn alloc(&mut self, item: T) -> usize

Allocates a space and populates it with item. No guarantees are made about the value of the returned index, except that it will remain valid until deallocated.

§Arguments

item - The item to allocate

§Returns

The index of the newly allocated item

Source

pub fn alloc_cyclic<F>(&mut self, f: F) -> usize
where F: FnOnce(usize) -> T,

Allocates a space and populates it with an item given by the closure f, which will receive the allocation index as a parameter. Useful for items that need to contain information about the index they are allocated in

§Arguments

f - A closure that will receive the index and return the item to populate with

§Returns

The index of the newly allocated space, equal to the index the closure sees

Source

pub fn dealloc(&mut self, index: usize) -> Option<T>

Deallocates the space at the given index if it is allocated.

§Arguments

index - The index of the space to deallocate

§Returns

Some if the space at the given index was allocated
None otherwise

Source

pub fn realloc(&mut self, index: usize, item: T) -> Result<T, T>

Replaces the element in the space at index, with item.

§Arguments

index - The index of the space whose item to replace
item - The item to replace with

§Returns

Ok<T> if the space was allocated, where T is the previous value. After this method returns Ok the space at index is to be considered populated with item.
Err containing item if the space was unallocated.

Source

pub fn is_allocated(&self, index: usize) -> bool

§Arguments

index - The index of the space to check

§Returns

Whether an element is allocated at the given index

Source

pub fn len(&self) -> usize

§Returns

The total number of allocated elements

Source

pub fn is_empty(&self) -> bool

§Returns

True if there are no allocated elements

Source

pub fn vec_len(&self) -> usize

§Returns

The length of the underlying Vec

Source

pub fn capacity(&self) -> usize

§Returns

The capacity of the underlying Vec

Source

pub fn enumerate(&self) -> impl Iterator<Item = (usize, &T)> + '_

Returns an immutable iterator over the populated spaces that acts in a way similar to .iter().enumerate() except the index actually represents an allocation

Source

pub fn enumerate_mut(&mut self) -> impl Iterator<Item = (usize, &mut T)> + '_

Returns a mutable iterator over the populated spaces that acts in a way similar to .iter_mut().enumerate() except the index actually represents an allocation

Source