anchor.diff:              faceVertexCount  : int
               vertexCount      : int
               indices          : BufferView
  -            uniforms         : SymbolDict<IMod>
  -            vertexAttributes : SymbolDict<BufferView>
  +            uniforms         : Map<Symbol, IMod>
  +            vertexAttributes : Map<Symbol, BufferView>
           }
   
       [<CompilationRepresentation(CompilationRepresentationFlags.ModuleSuffix)>]
  
positive.code:         interface IMod<IBuffer> with
              member x.GetValue c = x.GetValue c
  
      type ManagedPool(runtime : IRuntime) =
          let mutable count = 0
          let indexManager = MemoryManager.createNop()
          let vertexManager = MemoryManager.createNop()
          let instanceManager = MemoryManager.createNop()
          let indexBuffer = new ManagedBuffer(runtime)
          let vertexBuffers = SymbolDict<ManagedBuffer>()
          let instanceBuffers = SymbolDict<ManagedBuffer>()
          let isEmpty = Mod.init true
  
          let getVertexBuffer (sym : Symbol) =
              vertexBuffers.GetOrCreate(sym, fun sym -> new ManagedBuffer(runtime))
  
          let getInstanceBuffer (sym : Symbol) =
              instanceBuffers.GetOrCreate(sym, fun sym -> new ManagedBuffer(runtime))
  
          member x.IsEmpty = isEmpty :> IMod<_>
  
  
negative.code: 
  
      let testSg (r : IRuntime) =
  
          let signature =
              {
                  mode                = IndexedGeometryMode.TriangleList
                  vertexBufferTypes   = Map.ofList [ DefaultSemantic.Positions, typeof<V3f>; DefaultSemantic.Normals, typeof<V3f> ]
                  uniformTypes        = Map.ofList [ Symbol.Create "Hugo", typeof<M44f> ]
                  indexType           = typeof<int>
              }
  
          let pool = ManagedPool(r, signature)
  
          let geometry (pos : V3d) =
              let g = Primitives.unitSphere 0 |> AdaptiveGeometry.ofIndexedGeometry
              { g with uniforms = Map.add (Sym.ofString "Hugo") (Mod.constant ((M44d.Translation pos * M44d.Scale 0.1) |> M44f.op_Explicit) :> IMod) g.uniforms }
  
          let s = 30.0
          let drawCalls =
  