anchor.diff:              XAttribute(NsNone + "Id", key), 
               XAttribute(NsNone + "Background", value))
   
  -    allCategories |> Seq.map generateCategory
  +    let res = (allCategories |> Seq.map generateCategory)
  +    seq {
  +        yield! (allCategories |> Seq.map generateCategory)
  +        yield XElement(NsDgml + "Category", 
  +                XAttribute(NsNone + "Id", "Contains"), 
  +                XAttribute(NsNone + "Label", "Contains"), 
  +                XAttribute(NsNone + "IsContainment", "True"),
  +                XAttribute(NsNone + "CanBeDataDriven", "False"),
  +                XAttribute(NsNone + "CanLinkedNodesBeDataDriven", "True"),
  +                XAttribute(NsNone + "IncomingActionLabel", "Contained By"),
  +                XAttribute(NsNone + "OutgoingActionLabel", "Contains"))
  +    }
   
   let GraphContent (antho : Anthology) (viewName : string) =
       let projects = FindViewProjects viewName |> Set
       let xNodes = XElement(NsDgml + "Nodes", GraphNodes antho projects)
       let xLinks = XElement(NsDgml+"Links", GraphLinks projects)
       let xCategories = XElement(NsDgml + "Categories", GraphCategories ())
  -    let xGraphDir = XAttribute(NsNone + "GraphDirection", "LeftToRight")
  +    let xGraphDir = XAttribute(NsNone + "GraphDirection", "TopToBottom")
       let xLayout = XAttribute(NsNone + "Layout", "Sugiyama")
       XDocument(
           XElement(NsDgml + "DirectedGraph", xLayout, xGraphDir, xNodes, xLinks, xCategories))
  
positive.code:     let allAssemblies = projects |> Seq.map (fun x -> x.AssemblyReferences)
                                  |> Seq.concat
      seq {
          for project in projects do
              yield XElement(NsDgml + "Node",
                        XAttribute(NsNone + "Id", project.ProjectGuid),
                        XAttribute(NsNone + "Label", project.Output.Print()),
                        XAttribute(NsNone + "Category", "Project"))
  
          for project in importedProjects do
              yield XElement(NsDgml + "Node",
                        XAttribute(NsNone + "Id", project.ProjectGuid),
                        XAttribute(NsNone + "Label", project.Output.Print()),
                        XAttribute(NsNone + "Category", "ProjectImport"))
  
          for package in allPackageReferences do
              yield XElement(NsDgml + "Node",
                          XAttribute(NsNone + "Id", package.Print()),
                          XAttribute(NsNone + "Label", package.Print()),
                          XAttribute(NsNone + "Category", "Package"))
  
          for assembly in allAssemblies do
               yield XElement(NsDgml + "Node",
                        XAttribute(NsNone + "Id", assembly.Print()),
                        XAttribute(NsNone + "Label", assembly.Print()),
                        XAttribute(NsNone + "Category", "Assembly"))
      }
  
  let GraphLinks (projects : Project seq) =
      seq {
          for project in projects do
              let generateLink target category = 
                  XElement(NsDgml + "Link",
                                XAttribute(NsNone + "Source", project.ProjectGuid),
                                XAttribute(NsNone + "Target", target),
                                XAttribute(NsNone + "Category", category))
  
              for projectRef in project.ProjectReferences do
                  yield generateLink (projectRef.Print()) "ProjectRef"
  
              for package in project.PackageReferences do
                  yield generateLink (package.Print()) "PackageRef"
  
              for assembly in project.AssemblyReferences do
                  yield generateLink (assembly.Print()) "AssemblyRef"
      }
  
  let GraphCategories () =
  
negative.code:     slnDefines.Save (slnDefineFile.FullName)
  
  
  let GenerateNode source label category =
      XElement(NsDgml + "Node",
          XAttribute(NsNone + "Id", source),
          XAttribute(NsNone + "Label", label),
          XAttribute(NsNone + "Category", category))
  
  let GenerateLink source target category =
      XElement(NsDgml + "Link",
          XAttribute(NsNone + "Source", source),
          XAttribute(NsNone + "Target", target),
          XAttribute(NsNone + "Category", category))
  
  let GraphNodes (antho : Anthology) (projects : Project set) =
      let allReferencedProjects = projects |> Seq.map (fun x -> x.ProjectReferences)
                                           |> Seq.concat
  