queue

Overview

prototype::queue<T, Container> is a FIFO (First-In, First-Out) container adaptor. It wraps an underlying container (default: deque) and exposes only queue operations.

When to Use

• Task scheduling, message passing
• BFS traversal
• Producer-consumer patterns (single-threaded)

API Reference

namespace prototype {

template <typename T, typename Container = deque<T>>
class queue {
public:
    queue();

    T& front();
    T& back();
    bool empty() const;
    size_t size() const;
    void push(const T& value);
    void push(T&& value);
    void pop();
    void swap(queue& other);
};

} // namespace prototype

Example Code

#include <prototype/containers/queue.hpp>

prototype::queue<int> task_queue;
task_queue.push(1);
task_queue.push(2);

while (!task_queue.empty()) {
    int task = task_queue.front();
    task_queue.pop();
    execute(task);
}

Performance Characteristics

Operation	Complexity	Notes
push	O(1) amortized
pop	O(1)
front/back	O(1)

Design Notes

• For multi-threaded producer-consumer, use spsc_queue instead
• Use ring_buffer for fixed-capacity FIFO with overwrite semantics