Pico: Scheme for mere mortals

A Linked List in C++
template class List
{
public:
! struct Node
! {
! ! Node(const T& data, Node* next=0):data(data),next(next) {}
! ! Node* next;
! ! T data; ! void swap(List& x)
! };
! {
!
! ! Node* tmp = head; head = x.head; x.head = tmp;
List() : head(0) ! {}}
! List(const List& ! L) List& : head(0) operator=(const List& x)
! {
! {
! ! for ( const ! Node* ! List i = L.begin(); tmp(x); i!= L.end(); i=i->next )
! ! ! push_front(i->data);
! ! swap(tmp);
! ! reverse(); ! ! return *this;
! }
! }
C++ = 10 12
! void reverse() ! ~List() { clear(); }
! {
! void clear() { while (!empty()) ! T& front() pop_front(); { return } head->data; }
! ! Node* p = 0; Node* i = begin(); Node* n;
! const T& front() const { return head->data; }
! ! while (i)! bool empty() { return !head; }
! ! {
! Node* begin() { return head; }
! ! ! n = i->next;
! void push_front(const ! T& x) Node* { end() { return 0; }
! ! ! i->next ! = ! p; Node* tmp = new Node(x,head); head = tmp;
! ! ! p = i; ! i } = n;
! const Node* begin() const { return head; }
! ! }
! const Node* end() const { return 0; }
! ! head = p; ! void pop_front() {
! }
! ! if (head) { Node* private: tmp = head; head=head->next; delete tmp; }
! }
! Node* head;
};