CppUtils::Thread::Accessor<class T, class Mutex = std::mutex>

RAII accessor providing exclusive read and write access to a protected value.

Description

Does not own the value, only holds a reference and manages the underlying lock guard.

Related guide

Check out the RAII synchronization guide for detailed explanations and usage examples.

Template parameter	Description
T	The type of the value being accessed.
Mutex	The mutex type used for synchronization (defaults to std::mutex).

Public methods & functions

explicit constexpr Accessor::Accessor(Mutex& mutex, T& value);

Constructs an accessor by acquiring a unique lock on the provided mutex.

Parameter	Description
mutex	Mutex to lock.
value	Reference to the value to protect.

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[[nodiscard]] constexpr auto Accessor::value(this auto&& self [[clang::lifetimebound, msvc::lifetimebound]]) noexcept -> decltype(auto);

Returns a reference to the protected value.

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[[nodiscard]] constexpr auto Accessor::operator->(this auto&& self [[clang::lifetimebound, msvc::lifetimebound]]) noexcept -> auto*;

Accesses member functions or fields of the protected value.

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[[nodiscard]] constexpr auto Accessor::operator*(this auto&& self [[clang::lifetimebound, msvc::lifetimebound]]) noexcept -> decltype(auto);

Dereferences to obtain the protected value (equivalent to calling value()).

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[[nodiscard]] constexpr auto Accessor::getLockGuard(this auto&& self [[clang::lifetimebound, msvc::lifetimebound]]) noexcept -> auto&;

Returns a reference to the underlying std::unique_lock guard.

Provides direct access to the lock guard, allowing it to be used with synchronization primitives requiring a std::unique_lock (such as std::condition_variable::wait).

When used with std::condition_variable::wait, the wait function atomically releases the mutex while placing the thread to sleep, and re-acquires the lock upon waking before returning once the predicate evaluates to true:

auto accessor = queue.access();
condition.wait(accessor.getLockGuard(), [&] {
    return not std::ranges::empty(accessor.value());
});
auto item = accessor->pop();

Returns: Reference to the internal std::unique_lock<Mutex>.

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