Tree find

The tree find function is used to find a Node (Option<Rc<RefCell<Node<T>>>>) corresponding to a given key reference. It recursively visit tree's left or right branches - till it finds the node or returns None otherwise.

Following is the find function defintion:

    //Find the node containing the supplied key reference
    fn find(&self, key: &T) -> Option<Rc<RefCell<Node<T>>>> {
        match self.0 {
            Some(ref node) if node.borrow().key() == key => Some(Rc::clone(node)),
            Some(ref node) if node.borrow().key() > key => match node.borrow().left {
                Some(ref left) => Self::find(&left.borrow(), key),
                None => None,
            },
            Some(ref node) if node.borrow().key() < key => match node.borrow().right {
                Some(ref right) => Self::find(&right.borrow(), key),
                None => None,
            },
            Some(_) => None, //Make the compiler happy
            None => None,
        }
    }

Now with find function in place, next we will look at tree's delete function. But before that we will look at Node::delete function because tree's delete is heavily dependent on Node::delete.