sqlalchemy.event.attr.

class documentation

class _EmptyListener(_InstanceLevelDispatch[_ET]): (source)

Serves as a proxy interface to the events served by a _ClsLevelDispatch, when there are no instance-level events present. Is replaced by _ListenerCollection when instance-level events are added.

Method	`__bool__`	Undocumented
Method	`__call__`	Execute this event.
Method	`__contains__`	Undocumented
Method	`__init__`	Undocumented
Method	`__iter__`	Undocumented
Method	`__len__`	Undocumented
Method	`append`	Undocumented
Method	`clear`	Undocumented
Method	`exec_once`	Undocumented
Method	`exec_once_unless_exception`	Undocumented
Method	`for_modify`	Return an event collection which can be modified.
Method	`insert`	Undocumented
Method	`remove`	Undocumented
Class Variable	`__slots__`	Undocumented
Class Variable	`listeners`	Undocumented
Class Variable	`propagate`	Undocumented
Instance Variable	`name`	Undocumented
Instance Variable	`parent`	Undocumented
Instance Variable	`parent_listeners`	Undocumented
Method	`_needs_modify`	Undocumented

Inherited from _InstanceLevelDispatch:

Method	`_adjust_fn_spec`	Undocumented
Method	`_exec_w_sync_on_first_run`	Undocumented

Inherited from RefCollection (via _InstanceLevelDispatch):

Class Variable	`ref`	Undocumented
Method	`_memoized_attr_ref`	Undocumented

Inherited from MemoizedSlots (via _InstanceLevelDispatch, RefCollection):

Method	`__getattr__`	Undocumented
Method	`_fallback_getattr`	Undocumented

def __bool__(self) -> bool: (source) ¶

overrides sqlalchemy.event.attr._InstanceLevelDispatch.__bool__

Undocumented

def __call__(self, *args: Any, **kw: Any): (source) ¶

overrides sqlalchemy.event.attr._InstanceLevelDispatch.__call__

Execute this event.

def __contains__(self, item: Any) -> bool: (source) ¶

overrides sqlalchemy.event.attr._InstanceLevelDispatch.__contains__

Undocumented

def __init__(self, parent: _ClsLevelDispatch[_ET], target_cls: Type[_ET]): (source) ¶

Undocumented

def __iter__(self) -> Iterator[_ListenerFnType]: (source) ¶

overrides sqlalchemy.event.attr._InstanceLevelDispatch.__iter__

Undocumented

def __len__(self) -> int: (source) ¶

overrides sqlalchemy.event.attr._InstanceLevelDispatch.__len__

Undocumented

def append(self, *args: Any, **kw: Any) -> NoReturn: (source) ¶

overrides sqlalchemy.event.attr._InstanceLevelDispatch.append

Undocumented

def clear(self, *args: Any, **kw: Any) -> NoReturn: (source) ¶

Undocumented

def exec_once(self, *args: Any, **kw: Any) -> NoReturn: (source) ¶

overrides sqlalchemy.event.attr._InstanceLevelDispatch.exec_once

Undocumented

def exec_once_unless_exception(self, *args: Any, **kw: Any) -> NoReturn: (source) ¶

overrides sqlalchemy.event.attr._InstanceLevelDispatch.exec_once_unless_exception

Undocumented

def for_modify(self, obj: _DispatchCommon[_ET]) -> _ListenerCollection[_ET]: (source) ¶

overrides sqlalchemy.event.attr._InstanceLevelDispatch.for_modify

Return an event collection which can be modified. For _EmptyListener at the instance level of a dispatcher, this generates a new _ListenerCollection, applies it to the instance, and returns it.