///////////////////////////////////////////////////////////
// IteratorExamples.cpp - illustrate use of STL Iterator //
//                                                       //
// Jim Fawcett, CSE776 - Design Patterns, Summer 2009    //
///////////////////////////////////////////////////////////

#include <vector>
#include <list>
#include <string>
#include <iostream>
#include <algorithm>
//#include <iterator>

/////////////////////////////////////////////////////////////////////////
// Please read this brilliant article on what is wrong with STL iterators
// by one of the smartest authors around, Andre Alexandrescu
//   www.boostcon.com/site-media/var/sphene/.../iterators-must-go.pdf 

template <typename C>
void usesIterator(C& c)
{
  typename C::iterator iter = c.begin();
  std::cout << "\n  ";
  while(iter != c.end())
    std::cout << *iter++ << " ";
  iter = c.begin();
  std::cout << "\n  " << *iter;
  std::cout << "\n";
}

void usesForeach(std::vector<std::string>& tests)
{
  class myOp
  {
  public:
    myOp() { std::cout << "\n  "; }
    ~myOp() { std::cout << "\n--"; }
    void operator()(const std::string& s) { std::cout << s.c_str() << " "; } 
  };

  std::for_each(tests.begin(), tests.end(), myOp());
}

template <typename T>
class myTemplateOp
{
public:
  myTemplateOp() { std::cout << "\n  "; }
  ~myTemplateOp() { std::cout << "\n=="; }
  void operator()(const T& t) { std::cout << t << " "; } 
};

template <typename C>
void usesTemplateForeach(C& c)
{
  std::for_each(c.begin(), c.end(), myTemplateOp<C::value_type>());
}

void main()
{
  std::cout << "\n  Demonstrating use of STL iterators";
  std::cout << "\n ====================================\n";

  std::string test[] = { "test1", "test2", "test3", "test4", "test5" };

  std::cout << "\n  Iterating through native array";
  std::cout << "\n --------------------------------";
  std::string* niter = &test[0];
  std::cout << "\n  ";
  while(niter != &test[5])
    std::cout << *niter++ << " ";
  niter = &test[0];
  std::cout << "\n  " << *niter;
  std::cout << "\n";

  std::cout << "\n  Iterating through std::vector";
  std::cout << "\n -------------------------------";
  std::vector<std::string> tests(&test[0],&test[5]);
  std::vector<std::string>::iterator iter = tests.begin();
  usesIterator(tests);

  std::cout << "\n  Iterating std::vector with for_each and functor";
  std::cout << "\n -------------------------------------------------";
  usesForeach(tests);

  std::cout << "\n  Iterating std::vector with for_each and template functor";
  std::cout << "\n -----------------------------------------------------------";
  usesTemplateForeach(tests);

  std::cout << "\n  Iterating std::list with for_each and template functor";
  std::cout << "\n --------------------------------------------------------";
  int ints[] = { 1, 2, 3, 4, 3, 2 };
  std::list<int> lint(&ints[0], &ints[6]);
  usesTemplateForeach(lint);
}