/// remove existing value
/// if successful, remove are added to history
remove existing value
if successful, remove are added to history
remove existing value if successful remove are added to history
pub fn remove<Q: ?Sized>(&mut self, k: &Q) -> Option<EpochCounter<V>>
        where
            K: Borrow<Q>,
            Q: Hash + Eq,
            V: Clone,
        {
            if let Some((_, mut old_value)) = self.map.remove_entry(k) {
                old_value.set_epoch(self.epoch.epoch());
                self.deleted.push(old_value.clone());
                Some(old_value)
            } else {
                None
            }
        }
pub fn remove < Q : ? Sized > ( & mut self , k : & Q ) -> Option < EpochCounter < V > > where K : Borrow < Q > , Q : Hash + Eq , V : Clone , { if let Some ( ( _ , mut old_value ) ) = self . map . remove_entry ( k ) { old_value . set_epoch ( self . epoch . epoch ( ) ) ; self . deleted . push ( old_value . clone ( ) ) ; Some ( old_value ) } else { None } }
remove existing value
if successful, remove are added to history
remove existing value if successful remove are added to history
&mut self
k
&Q