diff options
Diffstat (limited to 'lib/sqlalchemy/event/api.py')
| -rw-r--r-- | lib/sqlalchemy/event/api.py | 34 |
1 files changed, 18 insertions, 16 deletions
diff --git a/lib/sqlalchemy/event/api.py b/lib/sqlalchemy/event/api.py index 3a6c46e6a..33a6b817f 100644 --- a/lib/sqlalchemy/event/api.py +++ b/lib/sqlalchemy/event/api.py @@ -11,6 +11,15 @@ CANCEL = util.symbol('CANCEL') NO_RETVAL = util.symbol('NO_RETVAL') +def _event_key(target, identifier, fn): + for evt_cls in _registrars[identifier]: + tgt = evt_cls._accept_with(target) + if tgt is not None: + return _EventKey(target, identifier, fn, tgt) + else: + raise exc.InvalidRequestError("No such event '%s' for target '%s'" % + (identifier, target)) + def listen(target, identifier, fn, *args, **kw): """Register a listener function for the given target. @@ -31,14 +40,7 @@ def listen(target, identifier, fn, *args, **kw): """ - for evt_cls in _registrars[identifier]: - tgt = evt_cls._accept_with(target) - if tgt is not None: - _EventKey(target, identifier, fn, tgt).listen(*args, **kw) - break - else: - raise exc.InvalidRequestError("No such event '%s' for target '%s'" % - (identifier, target)) + _event_key(target, identifier, fn).listen(*args, **kw) def listens_for(target, identifier, *args, **kw): @@ -87,13 +89,13 @@ def remove(target, identifier, fn): .. versionadded:: 0.9.0 """ - for evt_cls in _registrars[identifier]: - tgt = evt_cls._accept_with(target) - if tgt is not None: - _EventKey(target, identifier, fn, tgt).remove() - break - else: - raise exc.InvalidRequestError("No such event '%s' for target '%s'" % - (identifier, target)) + _event_key(target, identifier, fn).remove() + +def contains(target, identifier, fn): + """Return True if the given target/ident/fn is set up to listen. + .. versionadded:: 0.9.0 + + """ + return _event_key(target, identifier, fn).contains() |