Something close would be C++ private base classes with non-virtual base methods statically invoked by child methods? For example, some C++ types like std::strin

Something close would be C++ private base classes with non-virtual base methods statically invoked by child methods? For example, some C++ types like std::string and glibc's std::vector/shared_ptr/refcounts perform inheritance of base classes (some public, some private implementation details), and call virtual or statically dispatched methods on base classes.