anchor.diff:              /// <summary>
               ///     Set of nodes in the control-flow graph.
               /// </summary>
  -            Nodes: Map<NodeID, ViewExpr<SVGView> * NodeKind>
  +            Nodes: Map<NodeID, ViewExpr<GView<Sym<Var>>> * NodeKind>
   
               /// <summary>
               ///     Set of edges in the control-flow graph.
  
positive.code:           /// <summary>
            ///     The view of the destination node.
            /// </summary>
            DestView : ViewExpr<SVGView>
            /// <summary>
            ///      The command this edge represents.
            /// </summary>
  
negative.code:         /// </summary>
          Contents : Map<
              NodeID,
              (ViewExpr<GView<Sym<Var>>>
               * Set<OutEdge>
               * Set<InEdge>
               * NodeKind)> }
  