showx (POk env toks result)
 = "\n\nSucceeded, with:\n   Size env = " ++ show (length env) ++
   "\n   Next token = " ++ show (head toks) ++
   "\n\n   Result = " ++ show result ++ "\n\n"
showx (POk env toks result)
 = "\n\nSucceeded, with:\n   Size env = " ++ show (length env) ++
   "\n   Next token = " ++ show (head toks) ++
   "\n\n   Result = " ++ show result ++ "\n\n"
showx (POk env toks result)
 = "\n\nSucceeded, with:\n   Size env = " ++ show (length env) ++
   "\n   Next token = " ++ show (head toks) ++
   "\n\n   Result = " ++ show result ++ "\n\n"