fix a slice issue with precedences.

2014-04-21 02:30:17 +02:00
parent e320c3a8a0
commit eaf54942fc
5 changed files with 15 additions and 3 deletions
@@ -183,7 +183,8 @@ def calculate(evaluator, left_result, operator, right_result):
        return result
    else:
        if not left_result or not right_result:
-            return left_result + right_result
+            # illegal slices e.g. cause left/right_result to be None
+            return (left_result or []) + (right_result or [])

        for left in left_result:
            for right in right_result: