anchor.diff:          let setter = name => O ^-> Float * Float
           [getter; setter]
   
  +    /// Pseudo-property getting and setting a 2-element double array [x,y,z].
  +    let propF3 self name : list<CodeModel.Member> =
  +        let getter =
  +            (name => Float * Float * Float ^-> self)
  +            |> WithInline (sprintf "$0.%s([$1,$2,$3])" name)
  +        let setter = name => O ^-> Float * Float * Float
  +        [getter; setter]
  +
  +    /// Pseudo-property getting and setting something of the form [[x,y],[a,b]] with all floats.
  +    let propF4 self name : list<CodeModel.Member> =
  +        let getter =
  +            (name => Float2T * Float2T ^-> self)
  +            |> WithInline (sprintf "$0.%s([$1,$2])" name)
  +        let setter = name => O ^-> Float2T * Float2T
  +        [getter; setter]
  +
       let Cluster =
           let self = Type.New()
           ChainedClass "Cluster" self <| fun chained ->
  
positive.code:         |>! addToClassList
  
      let Projection =
          ChainedClassNew "Projection" <| fun chained ->
          [
              "apply"      => Float2T?location ^-> Float2T |> WithInline "$this($location)"
              "invert"     => Float2T?location ^-> Float2T
              "rotate"     => getSetVal chained Float3T
              "center"     => getSetVal chained Float2T
              "translate"  => getSetVal chained Float2T
              "scale"      => getSetVal chained Float
              "clipAngle"  => getSetVal chained Float
              "clipExtent" => getSetVal chained Float2x2T
              "precision"  => getSetVal chained Int
              "stream"     => Listener?listener ^-> Listener
          ]
  
      let AlbersProjection =
          ChainedClassNewInherits "AlbersProjection" Projection <| fun chained ->
          [
              "parallels" => getVal Float2T + chained Float2T
          ]
  
      let StreamTransform =
          ChainedClassNew "StreamTransform" <| fun chained ->
  
negative.code:             "revalue"  => chained HierarchyNode?root
          ]
  
      let binningFunc = Float2T?range * !|Obj * Int ^-> !|Float
  
      let Histogram =
          ChainedClassNew "Histogram" <| fun chained ->
  