anchor.diff:          NodesToVisit: Set<int> }
   
       let rec buildForVar (varRef: IReferenceExpression) (cfgInfo: CSharpCFGInfo) = 
  -        let addNodeUsingFun treeNode label addFunc (state: BuildState) =
  +        let addNodeAsConnectionNode treeNode label (state: BuildState) =
               let nodeId, provider' = NodeIdProviderFuncs.getId state.Provider treeNode
               let nodeInfo = { Label = label; AstElem = treeNode }
  -            let graph' = addFunc state.GraphInfo nodeId (InnerNode(nodeInfo))
  +            let graph' = DDGBuildFuncs.addConnectionNodeAndEdge state.GraphInfo nodeId (InnerNode(nodeInfo))
               { state with GraphInfo = graph'; Provider = provider' }
  -
  -        let addNodeAsConnectionNode treeNode label (state: BuildState) =
  -            let addFun = DDGBuildFuncs.addConnectionNodeAndEdge
  -            addNodeUsingFun treeNode label addFun state
   
           let setGraphConnectionNode nodeId (state: BuildState) =
               let graph' = { state.GraphInfo with ConnectionNode = nodeId }
  
positive.code: 
      let private badIRefExprCastMsg = 
          "unable to perform cast to IReferenceExpression"
  
  
      let private emptyListPopMsg = "pop on empty list"
      let private emptyListVisitMsg = "visit on empty list"
  
negative.code:             let ddg' = addNodeAndEdge ddGraph srcNodeId srcNodeInfo
              { ddg' with ConnectionNode = srcNodeId }
  
      type private NodeIdProvider = {   
          NextId: int
          GeneratedIds: Dictionary<ITreeNode, int> } 
  