anchor.diff:            /// <summary>
             ///     The name of the destination node.
             /// </summary>
  -          DestName : string
  +          DestName : NodeID
             /// <summary>
             ///     The view of the destination node.
             /// </summary>
  
positive.code: ///     The edges of <paramref name="_arg1" />, as name-edge pairs.
  ///     This is wrapped in a Chessie result over <c>Error</c>.
  /// </returns>
  let axiomatiseGraph =
      mapEdges
          (fun { Name = n; SrcView = s ; DestView = t ; Command = c } ->
              (n, { Pre = match s with InnerView v -> v
  
negative.code:         /// <summary>
          ///     The given node was duplicated when trying to merge graphs.
          /// </summary>
          | DuplicateNode of id: NodeID
          /// <summary>
          ///     The given edge was duplicated when trying to merge graphs.
          /// </summary>
          | DuplicateEdge of id: EdgeID
  
  
  /// <summary>
  