What are weak pointers in C++?

What are weak pointers in C++?

Weak pointers are a type of smart pointer in C++ that do not manage the lifetime of the object they point to. They are used to break circular references.

How do weak pointers differ from shared pointers?

Shared pointers maintain a reference count to manage the object's lifetime, while weak pointers do not affect the reference count and can be used to observe an object without owning it.

Can you give an example of when to use weak pointers?

Sure! Use weak pointers when you have two objects that reference each other, preventing memory leaks. For instance, in a parent-child relationship where the parent holds a shared pointer to the child, and the child holds a weak pointer to the parent.

What happens if I try to access a weak pointer?

If you try to access a weak pointer, you need to convert it to a shared pointer first using the lock() method. If the object has been deleted, lock() will return a null shared pointer.