thread

namespace std {
    class thread;
 
    void swap(thread& x, thread& y) noexcept;
 
    bool operator==(thread::id x, thread::id y) noexcept;
    bool operator!=(thread::id x, thread::id y) noexcept;
 
    bool operator<(thread::id x, thread::id y) noexcept;
    bool operator<=(thread::id x, thread::id y) noexcept;
    bool operator>(thread::id x, thread::id y) noexcept;
    bool operator>=(thread::id x, thread::id y) noexcept;
 
    template<class CharT, class Traits>
    basic_ostream<CharT, Traits>& operator<<(basic_ostream<CharT, Traits>& out,
                                            thread::id id);
 
    template <class T> struct hash;
    template <> struct hash<thread::id>;
 
    namespace this_thread {
 
        thread::id get_id() noexcept;
        void yield() noexcept;
        template <class Clock, class Duration>
            void sleep_until(const chrono::time_point<Clock, Duration>& abs_time);
        template <class Rep, class Period>
            void sleep_for(const chrono::duration<Rep, Period>& rel_time);
 
    }
}

class thread {
 public:
    // types:
    class id;
    typedef /*implementation-defined*/ native_handle_type;
 
    // construct/copy/destroy:
    thread() noexcept;
    template <class F, class ...Args> explicit thread(F&& f, Args&&... args);
    ~thread();
    thread(const thread&) = delete;
    thread(thread&&) noexcept;
    thread& operator=(const thread&) = delete;
    thread& operator=(thread&&) noexcept;
 
    // members:
    void swap(thread&) noexcept;
    bool joinable() const noexcept;
    void join();
    void detach();
    id get_id() const noexcept;
    native_handle_type native_handle();
 
    // static members:
    static unsigned hardware_concurrency() noexcept;
};

class thread::id {
 public:
    id() noexcept;
};

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