{"ast_node_type":"function","tokens":[{"end":73,"kind":"keyword","start":0,"text":"pub"}]}
    pub fn iter(&self) -> impl DoubleEndedIterator<Item = (Idx<T>, &V)> {
    /// Returns an iterator over the arena indexes and values in the map.
        self.v.iter().enumerate().filter_map(|(idx, o)| Some((Self::from_idx(idx), o.as_ref()?)))