void unshift_string (List *stack, char *elem) { do_unshift (stack, elem, 1); }
std::codecvt_base::result unshift(State& state, Extern* first2, Extern* last2, Extern*& next2) const { return do_unshift(state, first2, last2, next2); }
void unshift (List *stack, void *elem) { do_unshift (stack, elem, 0); }