events.py 文件源码

def _listen(cls, target, identifier, fn, raw=False, propagate=False):
        if not raw:
            orig_fn = fn

            def wrap(state, *arg, **kw):
                return orig_fn(state.obj(), *arg, **kw)
            fn = wrap

        event.Events._listen(target, identifier, fn, propagate=propagate)
        if propagate:
            for mgr in target.subclass_managers(True):
                event.Events._listen(mgr, identifier, fn, True)