C++ std::queue::pop() calls destructor. What of pointer types?

Question

I have a std::queue that is wrapped as a templated class to make a thread-safe queue. I have two versions of this class: one that stores value types, one that s

Answer 1

Online sources are worth what you pay for them - get a proper reference like Josuttis's book. pop() does not "call the destructor" - it simply removes an element from the queue adaptor's underlying representation (by default a std::deque) by calling pop_front() on it. If the thing being popped has a destructor, it will be used when the popped object goes out of scope, but the queue class has nothing to do with it.