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/*
  CopyRight GPL 2004 mmc Mike Chirico mchirico@users.sourceforge.net
  Created: Sun Apr  4 23:47:32 EDT 2004

  This is an example of polymorphism. Take a look at print_list
  BjS spells it like void print_list(const list<Vehicle*>&s ) 
  but, here it's made to work with _vectors_, and _lists_.  The
  addition T, in the typename is not used here or needed.
  But, it shows more flexibility. In otherwords, it will 
  for multiple _abstract classes_.  

  So, putting in print_list(const list<Vehicle*>&s ) works for
  all derived classes from Vehicle...it prints out the correct
  p_data()

  The template <typename T, template <typename> class C> allows
  for any derived class to be used. However, here, so for, 
  Vehicle is the only derived class.

  So, it's polymorphism plus.

  Ref:
  http://cvs.sourceforge.net/viewcvs.py/cpearls/cpearls/src/development/class/derived


  output:

      passenger: 0
      model: Caprice Classic
      owner: Bob Anderson
      year_made: 0
      top_speed: 0
      color: undefined
      VIN: PKZ23483218
      
      passenger: 0
      model: Sun Fish
      owner: Bob Anderson
      year_made: 0
      top_speed: 0
      color: undefined
      LICENSE: NYNCWW98
      Type of boat: Sailboat
      
      model: Lawn-Boy: DuraForce
      owner: Bob Anderson
      blade length: 21
      
      Vector: 
      
      passenger: 0
      model: Caprice Classic
      owner: Bob Anderson
      year_made: 0
      top_speed: 0
      color: undefined
      VIN: PKZ23483218
      
      passenger: 0
      model: Sun Fish
      owner: Bob Anderson
      year_made: 0
      top_speed: 0
      color: undefined
      LICENSE: NYNCWW98
      Type of boat: Sailboat
      
      model: Lawn-Boy: DuraForce
      owner: Bob Anderson
      blade length: 21
      


      
*/
#include <iostream>
#include <list>
#include <vector>
#include <string>
using namespace std;

class  Vehicle {
protected:
  int passenger;
  string model;
  string owner;
  int year_made;
  int top_speed;
  string color;
public:
  Vehicle(): passenger(0),model("undefined"),owner("undefined"), year_made(0), top_speed(0), color("undefined") {}
  Vehicle(const string& model, const string& owner): passenger(0),model(model),owner(owner), year_made(0), top_speed(0), color("undefined") {}
  virtual void p_data() = 0;
  //virtual void set_year_made(const int year_made) { this->year_made=year_made; }

};

// Or, cleaner but less flexibility
//    void print_list(const list<Vehicle*>& s)
// Note, below works with Vectors for New Abstract Types
template <typename T, template <typename> class C>
void print_list(const C<T*>& s)
{
  for_each(s.begin(),s.end(),mem_fun(&Vehicle::p_data));
}


class Car : public Vehicle {
private:
  string vin_num;
public:
  Car() { }
  Car(const string& model, const string& owner): Vehicle(model,owner) {}
  Car(const string& model, const string& owner,const string& vin): Vehicle(model,owner),vin_num(vin) {}
  
  void p_data() {
    cout << endl;
    cout << "passenger: " << passenger << endl;
    cout << "model: " << model << endl;
    cout << "owner: " << owner << endl;
    cout << "year_made: " << year_made << endl;
    cout << "top_speed: " << top_speed << endl;
    cout << "color: " << color << endl;
    cout << "VIN: " << vin_num << endl;
  }
};


class Boat : public Vehicle {
private:
  string tofb;
  string lic;
public:
  Boat() { }
  Boat(const string& model, const string& owner): Vehicle(model,owner) {}
  Boat(const string& model, const string& owner,const string& tofb,const string& lic): 
    Vehicle(model,owner),tofb(tofb),lic(lic) {}
  
  void p_data() {
    cout << endl;
    cout << "passenger: " << passenger << endl;
    cout << "model: " << model << endl;
    cout << "owner: " << owner << endl;
    cout << "year_made: " << year_made << endl;
    cout << "top_speed: " << top_speed << endl;
    cout << "color: " << color << endl;
    cout << "LICENSE: " << lic << endl;
    cout << "Type of boat: " << tofb << endl;
  }
};


class Lawnmower : public Vehicle {
private:
  int blade_len;
public:
  Lawnmower() {}
  Lawnmower(const string& model, const string& owner,int blade_len)
                         : Vehicle(model,owner) , blade_len(blade_len) {}

  void p_data() {
    cout << endl;
    cout << "model: " << model << endl;
    cout << "owner: " << owner << endl;
    cout << "blade length: " << blade_len << endl;

  }

  
};





int main(void)
{
  Car c("Caprice Classic","Bob Anderson","PKZ23483218");
  Boat b("Sun Fish","Bob Anderson","Sailboat","NYNCWW98");
  Lawnmower lm("Lawn-Boy: DuraForce","Bob Anderson",21);

  list<Vehicle*> vl;
  vl.push_back(&c);
  vl.push_back(&b);
  vl.push_back(&lm);
  print_list(vl);

  vector<Vehicle*> vv;
  vv.push_back(&c);
  vv.push_back(&b);
  vv.push_back(&lm);
  cout << endl << "Vector: " << endl;
  print_list(vv);

}





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Chirico img Mike Chirico, a father of triplets (all girls) lives outside of Philadelphia, PA, USA. He has worked with Linux since 1996, has a Masters in Computer Science and Mathematics from Villanova University, and has worked in computer-related jobs from Wall Street to the University of Pennsylvania. His hero is Paul Erdos, a brilliant number theorist who was known for his open collaboration with others.


Mike's notes page is souptonuts. For open source consulting needs, please send an email to mchirico@gmail.com. All consulting work must include a donation to SourceForge.net.

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