Struct Deque 

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

A double-ended queue backed by two Vecs.

Elements pushed to the front go into front (reversed), elements pushed to the back go into back. All four operations (push_front, push_back, pop_front, pop_back) are amortized O(1).

Implementations

impl<T> Deque<T>

pub fn new() -> Self

Create a new empty deque.

pub fn len(&self) -> usize

Return the number of elements in the deque.

pub fn is_empty(&self) -> bool

Return true if the deque is empty.

pub fn push_front(&mut self, value: T)

Push value to the front of the deque.

pub fn push_back(&mut self, value: T)

Push value to the back of the deque.

pub fn pop_front(&mut self) -> Option<T>

Remove and return the front element, or None if empty.

pub fn pop_back(&mut self) -> Option<T>

Remove and return the back element, or None if empty.

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

Return a reference to the front element, or None if empty.

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

Return a reference to the back element, or None if empty.

Trait Implementations

impl<T> Default for Deque<T>

fn default() -> Self

Returns the “default value” for a type.