use DownloadObservationOp;
use ;
/// Carries one pure download observation.
pub type RuntimeObservation = DownloadObservationOp;
/// Sends download observations from the thread that retrieves.
pub type RuntimeObservationSender = ;
/// Receives what one running download states, for whoever attends to it.
pub type RuntimeObservationReceiver = ;
/// Constructs one observation channel without consuming its receiving end.
///
/// A download states what it does whether or not anybody reads it, so nothing here is asked and
/// nothing is answered: the retrieving thread never waits on whoever is watching.