LinkList VS. List
// Questions and Answers:
// Q. Should I use std::list or base::LinkedList?
// A. The main reason to use base::LinkedList over std::list is
// performance. If you don’t care about the performance differences
// then use an STL container, as it makes for better code readability.
// Comparing the performance of base::LinkedList<T> to std::list<T*>:
// * Erasing an element of type T* from base::LinkedList<T> is
// an O(1) operation. Whereas for std::list<T*> it is O(n).
// That is because with std::list<T*> you must obtain an
// iterator to the T* element before you can call erase(iterator).
// * Insertion operations with base::LinkedList<T> never require
// heap allocations.
// Q. How does base::LinkedList implementation differ from std::list?
// A. Doubly-linked lists are made up of nodes that contain “next” and
// “previous” pointers that reference other nodes in the list.
// With base::LinkedList<T>, the type being inserted already reserves
// space for the “next” and “previous” pointers (base::LinkNode<T>*).
// Whereas with std::list<T> the type can be anything, so the implementation
// needs to glue on the “next” and “previous” pointers using
// some internal node type.