// trick2.cpp - demonstrates operator* usage in Enforcer

#include <iostream>
#include <string>

typedef int expression;

class test2
{
public:
  test2(expression exp) : expr(exp) {}
  bool pos(expression exp)
  {
    return exp > 0;
  }
  expression& operator*()
  {
    if(pos(expr))
    {
      std::cout << "\n  expression is positive, ";
      return expr;
    }
    else
    {
      std::cout << "\n  expression is not positive, ";
      return expr;
    }
  }
private:
  expression expr;
};

void main()
{
  std::cout << "\n  Demonstrating Enforcer's operator* trick"
            << "\n ==========================================\n";

  test2 t1(2+3);
    std::cout << *t1 << " is value of expression";

  test2 t2(2-3);
    std::cout << *t2 << " is value of expression";

  std::cout << "\n\n";
}