38   T *front() { return First; }  in front()
39   const T *front() const { return First; }  in front()
44     First = Last = nullptr;  in clear()
51   Iterator begin() { return Iterator(First); }  in begin()
54   ConstIterator begin() const { return ConstIterator(First); }  in begin()
61   T *First = nullptr;  member
67     CHECK_EQ(First, nullptr);  in checkConsistency()
71     for (T *I = First;; I = I->Next) {  in checkConsistency()
82   using IntrusiveList<T>::First;
90       First = X;  in push_back()
100     X->Next = First;  in push_front()
101     First = X;  in push_front()
107     First = First->Next;  in pop_front()
108     if (!First)  in pop_front()
143       Last->Next = L->First;  in append_back()
152   using IntrusiveList<T>::First;
162       DCHECK_EQ(First->Prev, nullptr);  in push_front()
163       First->Prev = X;  in push_front()
165     X->Next = First;  in push_front()
166     First = X;  in push_front()
172     if (Y == First)  in insert()
188       First = X;  in push_back()
200     First = First->Next;  in pop_front()
201     if (!First)  in pop_front()
204       First->Prev = nullptr;  in pop_front()
222     if (First == X) {  in remove()
224       First = Next;  in remove()