# Deque

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Erlang only supports fast prepends to lists while appending requires a full copy. Getting the size of a list is also a
`O(n)` operation. This library implements a deque using two rotating lists to support fast append and prepend as well as
`O(1)` size via an internal counter.

## Features

- Bounded size
- `Enumerable` protocol
- `Collectable` protocol
- `Inspect` protocol

## Usage

Add it to `mix.exs`

```elixir
defp deps do
  [{:deque, "~> 1.0"}]
end
```

Then use it like other Elixir data structures.

```elixir
deque = Deque.new(5)
deque = Deque.appendleft(1)
deque = Deque.appendleft(2)
deque = Deque.appendleft(3)
3 = Deque.popleft()

[6, 7, 8, 9, 10] = Enum.into(0..10, Deque.new(5))
```

## License

Deque is released under [the MIT License](LICENSE).
Check [LICENSE](LICENSE) file for more information.