Aggregate two event values.
(self, val1, val2)
| 107 | return self._null |
| 108 | |
| 109 | def aggregate(self, val1, val2): |
| 110 | """Aggregate two event values.""" |
| 111 | assert val1 is not None |
| 112 | assert val2 is not None |
| 113 | return self._aggregator(val1, val2) |
| 114 | |
| 115 | def format(self, val): |
| 116 | """Format an event value.""" |