anchor.diff:      member this.UnregisterEntity<'t when 't : struct and 't :> Component> systemName entityId =
           match this.TryGetSystem<SystemCorrelated<'t, 'w>> systemName with
           | Some system ->
  -            if system.Unregister entityId this then
  +            if system.UnregisterEntity entityId this then
                   match correlations.TryGetValue entityId with
                   | (true, correlation) -> correlation.Add systemName
                   | (false, _) -> correlations.Add (entityId, List [systemName])
           | _ -> failwith ("Could not find expected system '" + systemName + "'.")
   
  -type [<AbstractClass>] SystemJunctioned<'t, 'w when 't : struct and 't :> Component>
  -    (junctionedSystemNames : string array) =
  +    member this.GetEntities<'t when 't : struct and 't :> Component> systemName =
  +        match this.TryGetSystem<SystemCorrelated<'t, 'w>> systemName with
  +        | Some system -> system.GetEntities ()
  +        | _ -> failwith ("Could not find expected system '" + systemName + "'.")
  +
  +type [<AbstractClass>] SystemJunctioned<'t, 'w when 't : struct and 't :> Component> (junctionedSystemNames : string array) =
       inherit SystemCorrelated<'t, 'w> ()
   
       let mutable junctionsOpt = None : Dictionary<string, 'w System> option
   
  -    override this.Register entityId ecs =
  +    override this.RegisterEntity entityId ecs =
           match Dictionary.tryGetValue entityId this.Correlations with
           | (false, _) ->
               let junctions = this.GetJunctions ecs
  
positive.code:         let index = this.GetComponentIndex entityId
          &components.[index]
  
      abstract member Register : Guid -> 'w Ecs -> int
      default this.Register entityId _ =
          match Dictionary.tryGetValue entityId correlations with
          | (false, _) ->
              let comp = Unchecked.defaultof<'t>
  
negative.code:             comp.RefCount <- inc comp.RefCount
              index
  
      abstract member UnregisterEntity : Guid -> 'w Ecs -> bool
      default this.UnregisterEntity entityId _ =
          match correlations.TryGetValue entityId with
          | (true, index) ->
              if index <> freeIndex then
  