Method pop

datafusion/execution/src/cache/lru_queue.rs:138–152

Removes and returns the least recently used value. Returns `None` if the queue is empty.

(&mut self)

    /// Removes and returns the least recently used value.
    /// Returns `None` if the queue is empty.
    pub fn pop(&mut self) -> Option<(K, V)> {
        let key_to_remove = self.queue.tail.as_ref().map(|n| {
            n.upgrade()
                .expect("value has been unexpectedly dropped")
                .lock()
                .key
                .clone()
        });
        if let Some(k) = key_to_remove {
            let value = self.remove(&k).unwrap(); // confirmed above that the entry exists
            Some((k, value))
        } else {
            None
        }
    }

    /// Removes a specific entry from the queue, if it exists.
    pub fn remove(&mut self, key: &K) -> Option<V> {