(self)
| 3006 | class madstring(str): |
| 3007 | _rev = None |
| 3008 | def rev(self): |
| 3009 | if self._rev is not None: |
| 3010 | return self._rev |
| 3011 | L = list(self) |
| 3012 | L.reverse() |
| 3013 | self._rev = self.__class__("".join(L)) |
| 3014 | return self._rev |
| 3015 | s = madstring("abcdefghijklmnopqrstuvwxyz") |
| 3016 | self.assertEqual(s, "abcdefghijklmnopqrstuvwxyz") |
| 3017 | self.assertEqual(s.rev(), madstring("zyxwvutsrqponmlkjihgfedcba")) |