egison-4.1.0: sample/ioRef.egi

def refTest x y :=
  do let w := newIORef ()
     writeIORef w x
     let w1 := readIORef w
     print (show w1)
     writeIORef w y
     let w2 := readIORef w
     print (show w2)
     flush ()

def main args := refTest 1 2