void->int filter Generate{
  int x=0;				//Note that native filters can have state.
  work push 1{
	push(x);
	x = x+1;
  }
}

int->void filter Read{
  work pop 1{    
	 print( pop() );
  } 
}


bit->bit filter BoolFilter{
  work push 2 pop 4{		
    //TODO: Add your code here.
  }	
}


void->void pipeline BoolFilterPL{
  add Generate();

  add BoolFilter();

  add Read();
}