pub fn as_subtree(&mut self) -> Option<&mut MenuTree> {
        match *self {
            MenuItem::Subtree(_, ref mut tree) => Some(Rc::make_mut(tree)),
            _ => None,
        }
    }
/// Return a mutable reference to the subtree, if applicable.
///
/// Returns `None` if `self` is not a `MenuItem::Subtree`.
Return a mutable reference to the subtree, if applicable.
Return a mutable reference to the subtree if applicable .
pub fn as_subtree(&mut self) -> Option<&mut MenuTree> {
        match *self {
            MenuItem::Subtree(_, ref mut tree) => Some(Rc::make_mut(tree)),
            _ => None,
        }
    }
pub fn as_subtree ( & mut self ) -> Option < & mut MenuTree > { match * self { MenuItem :: Subtree ( _ , ref mut tree ) => Some ( Rc :: make_mut ( tree ) ) , _ => None , } }
Return a mutable reference to the subtree, if applicable.
Return a mutable reference to the subtree if applicable .
&mut self
&mut self