Lists

struct Animal {
    const char* species_;
    list_links link_;

    Animal(const char* species)
        : species_(species) {
    }
};

list<Animal, &Animal::link_> animal_list;
    // that is, a “list of Animals, linked by the Animal::link_ member”

// list is initially empty
assert(animal_list.empty());

// add some Animals to it. Note that the `link_` members must be cleared
// before we add them; that is done automatically by the constructor, but
// in your buddy allocator you may need to call `...link_.reset()` explicitly
Animal dog("dog"), cat("cat"), capybara("capybara");
animal_list.push_back(&dog);
animal_list.push_front(&cat);
animal_list.push_back(&capybara);

for (Animal* a = animal_list.front(); a; a = animal_list.next(a)) {
    log_printf("%s\n", a->species_);
}
    // prints `cat`, `dog`, `capybara`

// remove an Animal from the list
animal_list.erase(&dog);

for (Animal* a = animal_list.front(); a; a = animal_list.next(a)) {
    log_printf("%s\n", a->species_);
}
    // prints `cat`, `capybara`