Method fmt

flow-rs/src/channel/error.rs:19–23

(&self, f: &mut std::fmt::Formatter<'_>)

impl<T> std::fmt::Debug for BatchRecvError<T> {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match *self {
            BatchRecvError::Closed(_) => f.write_str("BatchRecvError::Closed"),
        }
    }
}