pub fn pop_front(&mut self) -> Option<T> {
        match self.elements.remove(&self.next_expected_idx) {
            Some(value) => {
                self.next_expected_idx += 1;
                Some(value)
            }
            None => None,
        }
    }
/// Attempts to take the next element from the queue. Returns `None`
/// if either the queue is empty, or the next expected element is yet
/// missing in the queue.
Attempts to take the next element from the queue. Returns `None`
if either the queue is empty, or the next expected element is yet
missing in the queue.
Attempts to take the next element from the queue . Returns ` None ` if either the queue is empty or the next expected element is yet missing in the queue .
pub fn pop_front(&mut self) -> Option<T> {
        match self.elements.remove(&self.next_expected_idx) {
            Some(value) => {
                self.next_expected_idx += 1;
                Some(value)
            }
            None => None,
        }
    }
pub fn pop_front ( & mut self ) -> Option < T > { match self . elements . remove ( & self . next_expected_idx ) { Some ( value ) => { self . next_expected_idx += 1 ; Some ( value ) } None => None , } }
Attempts to take the next element from the queue.
Attempts to take the next element from the queue .
&mut self