{"ast_node_type":"other","tokens":[{"end":90,"kind":"keyword","start":0,"text":"///"}]}
    /// Ensures a value is in the entry by inserting the result of the default function if
impl<'map, A: ?Sized + Downcast, V: IntoBox<A>> Entry<'map, A, V> {
    /// empty, and returns a mutable reference to the value in the entry.