C++ with

gistfile1.cpp

template<typename TObj, typename TFn, typename... TArgs>
typename std::result_of<TFn(TArgs...)>::type with(TObj&& obj_, TFn fn, TArgs... args)
{
    TObj obj(std::move(obj_));
    return fn(std::foward(args)...);
}

template<typename TMutex>
std::lock_guard<TMutex>&& locked(TMutex& mtx)
{
    return std::move(std::lock_guard<TMutex>(mtx));
}

// use
with(locked(mutex), [&]{
   // do locked stuff
});