fn poll_purge(&mut self) -> Poll<(), ()> {
        loop {
            match try_ready!(self
                .expirations
                .poll()
                .map_err(|e| unreachable!("expiration must not fail: {}", e)))
            {
                None => {
                    self.purge_task = Some(task::current());
                    return Ok(Async::NotReady);
                }
                Some(key) => {
                    trace!("expiring an item from the cache");
                    self.values.remove(key.get_ref());
                }
            }
        }
    }
/// Evict expired values from the cache.
///
/// Polls the underlying `DelayQueue`. When elements are returned from the
/// queue, remove the associated key from `values`.
Evict expired values from the cache.
Polls the underlying `DelayQueue`. When elements are returned from the
queue, remove the associated key from `values`.
Evict expired values from the cache . Polls the underlying ` DelayQueue ` . When elements are returned from the queue remove the associated key from ` values ` .
fn poll_purge(&mut self) -> Poll<(), ()> {
        loop {
            match try_ready!(self
                .expirations
                .poll()
                .map_err(|e| unreachable!("expiration must not fail: {}", e)))
            {
                None => {
                    self.purge_task = Some(task::current());
                    return Ok(Async::NotReady);
                }
                Some(key) => {
                    trace!("expiring an item from the cache");
                    self.values.remove(key.get_ref());
                }
            }
        }
    }
fn poll_purge ( & mut self ) -> Poll < ( ) , ( ) > { loop { match try_ready ! ( self expirations poll ( ) map_err ( e unreachable ( " " e ) ) ) { None => { self . purge_task = Some ( task :: current ( ) ) ; return Ok ( Async :: NotReady ) ; } Some ( key ) => { trace ! ( " " ) ; self . values . remove ( key . get_ref ( ) ) ; } } } }
Evict expired values from the cache.
Evict expired values from the cache .
&mut self
&mut self