anchor.diff:        base.Put(string index, value)
   
       else
  -      if x.IsDense then
  +      if isDense then
           let ii = int index
           let denseLength = uint32 dense.Length
   
  
positive.code: 
        else
          if x.HasIndex(index) then
            if x.IsDense 
              then dense.[int index].Value
              else sparse.Get(index)
  
  
negative.code: 
    override x.ClassName = "Array"
  
    member x.IsDense = isDense
  
    ///
    override x.GetAllIndexProperties(dict:MutableDict<uint32, BV>, l) =
      if isDense then
        let length = int length
  
        for i = 0 to length-1 do
  