diff options
| -rw-r--r-- | pym/cache/template.py | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/pym/cache/template.py b/pym/cache/template.py index a628b1161..4ffd9b9ef 100644 --- a/pym/cache/template.py +++ b/pym/cache/template.py @@ -114,7 +114,14 @@ class database(object): raise NotImplementedError def __contains__(self, cpv): - raise NotImplementedError + """This method should always be overridden. It is provided only for + backward compatibility with modules that override has_key instead. It + will automatically raise a NotImplementedError if has_key has not been + overridden.""" + if self.has_key is database.has_key: + # prevent a possible recursive loop + raise NotImplementedError + return self.has_key(cpv) def get(self, k, x=None): try: |