#ifndef _checking_policy_
#define _checking_policy_


struct No_checking_policy {
  static void check_push(size_t,size_t) {};
  static void check_pop(size_t) {};
  static void check_top(size_t) {};
};

struct Abort_on_error_policy {
  static void check_push(size_t top,size_t size) {
   
    if(top >= size) {
      std::cerr<<"trying to push elemnt on full stack: aborting"<<std::endl;
      abort();
    }
  };
  
  static void check_pop(size_t top) {
      if(top == 0) {
      std::cerr<<"trying to pop an empty stack: aborting"<<std::endl;
      abort();
      }
  };
  static void check_top(size_t top) {
      if(top == 0) {
      std::cerr<<"trying to read from empty stack: aborting"<<std::endl;
      abort();
      }
  };
};

struct Std_exception_on_error_policy {

  static void check_push(size_t top,size_t size) {
   
    if(top >= size) {
      throw std::range_error("over the top");
    }
  };
  static void check_pop(size_t top) {
      if(top == 0) {
	throw std::range_error("poping empty");
      }
  };
  static void check_top(size_t top) {
      if(top == 0) {
	throw std::range_error("reading empty");
      }
  };

};
#endif