// Union returns an audit Backend which logs events to a set of backends. The returned // Sink implementation blocks in turn for each call to ProcessEvents. func Union(backends ...Backend) Backend { … } type union … func (u union) ProcessEvents(events ...*auditinternal.Event) bool { … } func (u union) Run(stopCh <-chan struct{ … } func (u union) Shutdown() { … } func (u union) String() string { … }