anchor.diff:  
   
           override x.Compute() =
  -            deleteOldBuffers()
  -
               buffer :> IBuffer
   
           member x.Dispose() =
  
positive.code: #nowarn "51"
  
  
  module MappedBufferImplementations = 
      type MappedBuffer(ctx : Context) =
          inherit Mod.AbstractMod<IBuffer>()
  
  
negative.code:         let locks = ReferenceCountingSet<RenderTaskLock>()
  
          let mutable oldBuffers : list<int> = []
          let mutable buffer = ResizeBuffers.ResizeBuffer(ctx, using ctx.ResourceLock (fun _ -> GL.GenBuffer()))
          let onDispose = new System.Reactive.Subjects.Subject<unit>()
  
          let resourceLocked f =
  