262     pub enum TryRecvError {  enum
281     impl fmt::Display for TryRecvError {  implementation
284                 TryRecvError::Empty => write!(f, "channel empty"),  in fmt()
285                 TryRecvError::Closed => write!(f, "channel closed"),  in fmt()
286                 TryRecvError::Lagged(amt) => write!(f, "channel lagged by {}", amt),  in fmt()
291     impl std::error::Error for TryRecvError {}  implementation
698     ) -> Result<RecvGuard<'_, T>, TryRecvError> {  in recv_ref()  argument
710                 return Err(TryRecvError::Empty);  in recv_ref()
759                     return Err(TryRecvError::Empty);  in recv_ref()
797                 return Err(TryRecvError::Lagged(missed));  in recv_ref()
804             return Err(TryRecvError::Closed);  in recv_ref()
922     pub fn try_recv(&mut self) -> Result<T, TryRecvError> {  in try_recv()  argument
924         guard.clone_value().ok_or(TryRecvError::Closed)  in try_recv()
941                 Err(TryRecvError::Closed) => break,  in drop()
943                 Err(TryRecvError::Lagged(..)) => {}  in drop()
945                 Err(TryRecvError::Empty) => panic!("unexpected empty broadcast channel"),  in drop()
988             Err(TryRecvError::Empty) => return Poll::Pending,  in poll()
989             Err(TryRecvError::Lagged(n)) => return Poll::Ready(Err(RecvError::Lagged(n))),  in poll()
990             Err(TryRecvError::Closed) => return Poll::Ready(Err(RecvError::Closed)),  in poll()