Struct ringbuffer::AllocRingBuffer

pub struct AllocRingBuffer<T> { /* fields omitted */ }

The AllocRingBuffer is a RingBufferExt which is based on a Vec. This means it allocates at runtime on the heap, and therefore needs the alloc crate. This struct and therefore the dependency on alloc can be disabled by disabling the alloc (default) feature.

Example

use ringbuffer::{AllocRingBuffer, RingBuffer, RingBufferExt, RingBufferWrite};

let mut buffer = AllocRingBuffer::with_capacity(2);

// First entry of the buffer is now 5.
buffer.push(5);

// The last item we pushed is 5
assert_eq!(buffer.get(-1), Some(&5));

// Second entry is now 42.
buffer.push(42);

assert_eq!(buffer.peek(), Some(&5));
assert!(buffer.is_full());

// Because capacity is reached the next push will be the first item of the buffer.
buffer.push(1);
assert_eq!(buffer.to_vec(), vec![42, 1]);

Implementations

impl<T> AllocRingBuffer<T>

pub fn with_capacity_unchecked(cap: usize) -> Self

Creates a AllocRingBuffer with a certain capacity. This capacity is fixed. for this ringbuffer to work, cap must be a power of two and greater than zero.

pub fn with_capacity_power_of_2(cap_power_of_two: usize) -> Self

Creates a AllocRingBuffer with a certain capacity. The actual capacity is the input to the function raised to the power of two (effectively the input is the log2 of the actual capacity)

pub fn with_capacity(cap: usize) -> Self

Creates a AllocRingBuffer with a certain capacity. The capacity must be a power of two.

Panics

Panics when capacity is zero or not a power of two

pub fn new() -> Self

Creates a AllocRingBuffer with a capacity of RINGBUFFER_DEFAULT_CAPACITY.

Trait Implementations

impl<T: Clone> Clone for AllocRingBuffer<T>

fn clone(&self) -> AllocRingBuffer<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for AllocRingBuffer<T>

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

Formats the value using the given formatter.

impl<T> Default for AllocRingBuffer<T>

fn default() -> Self

Creates a buffer with a capacity of crate::RINGBUFFER_DEFAULT_CAPACITY.

impl<T: Eq> Eq for AllocRingBuffer<T>

impl<RB> FromIterator<RB> for AllocRingBuffer<RB>

fn from_iter<T: IntoIterator<Item = RB>>(iter: T) -> Self

Creates a value from an iterator.

impl<T> Index<isize> for AllocRingBuffer<T>

type Output = T

The returned type after indexing.

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

Performs the indexing (container[index]) operation.

impl<T> IndexMut<isize> for AllocRingBuffer<T>

fn index_mut(&mut self, index: isize) -> &mut Self::Output

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

impl<T: PartialEq> PartialEq<AllocRingBuffer<T>> for AllocRingBuffer<T>

fn eq(&self, other: &AllocRingBuffer<T>) -> bool

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

fn ne(&self, other: &AllocRingBuffer<T>) -> bool

This method tests for !=.

impl<T> RingBuffer<T> for AllocRingBuffer<T>

fn capacity(&self) -> usize

Returns the capacity of the buffer.

fn len(&self) -> usize

Returns the length of the internal buffer. This length grows up to the capacity and then stops growing. This is because when the length is reached, new items are appended at the start.

fn is_empty(&self) -> bool

Returns true if the buffer is entirely empty.

fn is_full(&self) -> bool

Returns true when the length of the ringbuffer equals the capacity. This happens whenever more elements than capacity have been pushed to the buffer.

impl<T> RingBufferExt<T> for AllocRingBuffer<T>

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

Gets a value relative to the current index. 0 is the next index to be written to with push. -1 and down are the last elements pushed and 0 and up are the items that were pushed the longest ago.

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

Gets a value relative to the current index mutably. 0 is the next index to be written to with push. -1 and down are the last elements pushed and 0 and up are the items that were pushed the longest ago.

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

Gets a value relative to the start of the array (rarely useful, usually you want Self::get)

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

Gets a value mutably relative to the start of the array (rarely useful, usually you want Self::get_mut)

fn clear(&mut self)

Empties the buffer entirely. Sets the length to 0 but keeps the capacity allocated.

fn peek(&self) -> Option<&T>

Returns the value at the current index. This is the value that will be overwritten by the next push and also the value pushed the longest ago. (alias of Self::front)

fn front(&self) -> Option<&T>

Returns the value at the front of the queue. This is the value that will be overwritten by the next push and also the value pushed the longest ago. (alias of peek)

fn front_mut(&mut self) -> Option<&mut T>

Returns a mutable reference to the value at the back of the queue. This is the value that will be overwritten by the next push. (alias of peek)

fn back(&self) -> Option<&T>

Returns the value at the back of the queue. This is the item that was pushed most recently.

fn back_mut(&mut self) -> Option<&mut T>

Returns a mutable reference to the value at the back of the queue. This is the item that was pushed most recently.

fn iter_mut(&mut self) -> RingBufferMutIterator<'_, T, Self>

Creates a mutable iterator over the buffer starting from the item pushed the longest ago, and ending at the element most recently pushed.

fn iter(&self) -> RingBufferIterator<'_, T, Self>

Creates an iterator over the buffer starting from the item pushed the longest ago, and ending at the element most recently pushed.

fn to_vec(&self) -> Vec<T> where
    T: Clone, 

Converts the buffer to a vector. This Copies all elements in the ringbuffer.

fn contains(&self, elem: &T) -> bool where
    T: PartialEq, 

Returns true if elem is in the ringbuffer.

impl<T> RingBufferRead<T> for AllocRingBuffer<T>

fn dequeue_ref(&mut self) -> Option<&T>

dequeues the top item off the ringbuffer. Returns a reference to the item. This means that lifetimes will be problematic because as long as this reference exists, you can not push to the queue. To solve this, use the dequeue method. This requires the item to be clone. Easily moving out of the ringbuffer is sadly impossible.

fn skip(&mut self)

dequeues the top item off the queue, but does not return it. Instead it is dropped. If the ringbuffer is empty, this function is a nop.

fn dequeue(&mut self) -> Option<T> where
    T: Clone, 

dequeues the top item off the ringbuffer and returns a cloned version. See the dequeue_ref docs

fn drain(&mut self) -> RingBufferDrainingIterator<'_, T, Self> where
    T: Clone, 

Returns an iterator over the elements in the ringbuffer, dequeueing elements as they are iterated over.

impl<T> RingBufferWrite<T> for AllocRingBuffer<T>

fn push(&mut self, value: T)

Pushes a value onto the buffer. Cycles around if capacity is reached.

impl<T> StructuralEq for AllocRingBuffer<T>

impl<T> StructuralPartialEq for AllocRingBuffer<T>