Method uncle

src/tree/binary/node.rs:103–117

(node: Option<NonNull<Self>>)

    }

    pub fn uncle(node: Option<NonNull<Self>>) -> Option<NonNull<Self>> {
        unsafe {
            node.and_then(|node| {
                node.as_ref().parent.and_then(|parent| {
                    parent.as_ref().parent.and_then(|grandparent| {
                        if grandparent.as_ref().left == Some(parent) {
                            grandparent.as_ref().right
                        } else {
                            grandparent.as_ref().left
                        }
                    })
                })
            })
        }
    }
}

/// Node proxy, like jQuery