anchor.diff:  
           and convMethodRefToTgt (m: MethodInfo) =
               Debug.Assert((match m with :? ProvidedMethod as x -> not x.BelongsToTargetModel | _ -> true), "unexpected target ProvidedMethod")
  +            //Debug.Assert (m.Name <> "get_Item1" || m.DeclaringType.Name <> "Tuple`2")
               let declTyT = convTypeToTgt m.DeclaringType
               let mT =
                   if m.IsGenericMethod then
  
positive.code:         /// .NET symbolic types made from this type, e.g. when building Nullable<SomeProvidedType[]>.FullName
          override __.DeclaringType =
              match kind,typeArgs with
              | ProvidedSymbolKind.SDArray,[arg] -> arg
              | ProvidedSymbolKind.Array _,[arg] -> arg
              | ProvidedSymbolKind.Pointer,[arg] -> arg
              | ProvidedSymbolKind.ByRef,[arg] -> arg
              | ProvidedSymbolKind.Generic gty,_ -> gty
              | ProvidedSymbolKind.FSharpTypeAbbreviation _,_ -> null
              | _ -> failwith "unreachable"
  
  
negative.code:                 override __.DeclaringType = declTy
  
                  override __.EventHandlerType = inp.EventHandlerType |> txILType (gps, [| |])
                  override __.GetAddMethod(_nonPublic) = inp.AddMethod |> txILMethodRef declTy
                  override __.GetRemoveMethod(_nonPublic) = inp.RemoveMethod |> txILMethodRef declTy
                  override __.GetCustomAttributesData() = inp.CustomAttrs |> txCustomAttributesData
                  override __.MetadataToken = inp.Token
  
  