     }
 
 
-    ///
+    /// Extracts the Video Poster Attribute from a VideoAttachment Instance.
     ///
     private func videoPosterAttribute(from attachment: VideoAttachment) -> StringAttribute? {
         guard let poster = attachment.posterURL?.absoluteString else {

    }


    ///
    ///
    private func lengthOfElements(atColumnIndex index: Int, in branches: [Branch]) -> [ElementNode: Int] {
        var lengths = [ElementNode: Int]()

    }


    /// Determines the length of a Node, given a collection of branches.
    ///
    private func length(of element: ElementNode, in branches: [Branch]) -> Int {
        var length = 0
