import math2;
import c.stdio;
import c.stdlib;


class DivisionByZeroError: Error {

  this (char[] args){
    super(args);
  }
}

double test_1 (double a, double b)
     in {
  assert(! (feq(b, 0.0)));
}
out (result) {
  assert(feq(result, a / b));
}
body {
  return  a / b;
}

double test_2 (double a, double b){
  if (feq (b, 0.0)){
    throw new DivisionByZeroError("Division by zero");
  }
  return a / b;
}

  

  int main (){
    puts("Example for catching a contract violation");
    fflush(stdout);
    try {
      double result = test_1(10.0, 0.0);
    }
    catch (Object a){
        printf("You violated a preconditon of test_1\n");
    }
    

    try {
      double result = test_2(10.0, 0.0);
      printf("result = %lf\n", result);
    }
    catch (DivisionByZeroError e){
      e.print();
      exit(EXIT_FAILURE);
    }
    return 0;
  }