anchor.diff:      let freeList = HashSet<int> ()
       let preDeque = HashSet<int> ()
       let correlations = dictPlus [] : Dictionary<Guid, int>
  +    let correlationsBack = dictPlus [] : Dictionary<int, Guid>
   
       new (reserve) = SystemCorrelated (reserve, typeof<'c>.Name)
       new () = SystemCorrelated (Constants.Ecs.ArrayReserve, typeof<'c>.Name)
  
positive.code:                 if this.Components.[index].RefCount = 0 then this.FreeList.Add index |> ignore
              else this.FreeIndex <- dec this.FreeIndex
              comp.Disjunction junctions entityId ecs
              true
          | (false, _) -> false
  
  
negative.code:                 let index = Seq.head this.FreeList
                  let _ : bool = this.FreeList.Remove index
                  this.Correlations.Add (entityId, index)
                  this.CorrelationsBack.Add (index, entityId)
                  let mutable comp = comp.Junction systems entityId ecs
                  comp.RefCount <- inc comp.RefCount
                  this.Components.Array.[index] <- comp
  