Method insert

include/tscore/List.h:405–418

template <class C, class L>
inline void
DLL<C, L>::insert(C *e, C *after)
{
  if (!after) {
    push(e);
    return;
  }
  prev(e)     = after;
  next(e)     = next(after);
  next(after) = e;
  if (next(e)) {
    prev(next(e)) = e;
  }
}

template <class C, class L>
auto