anchor.diff:      type internal FsUnionPickler =
   
           static member Create<'Union> (resolver : IPicklerResolver) =
  +            if not <| typeof<'Union>.IsSerializable then
  +                raise <| new NonSerializableTypeException(typeof<'Union>)
  +
               // resolve tag reader methodInfo
               let tagReaderMethod =
                   match FSharpValue.PreComputeUnionTagMemberInfo(typeof<'Union>, allMembers) with
  
positive.code:     type internal FsExceptionPickler =
          
          static member Create<'Exception when 'Exception :> exn>(resolver : IPicklerResolver) =
              // the default ISerializable pickler that handles exception metadata serialization
              let defPickler = ISerializablePickler.Create<'Exception>(resolver) :?> CompositePickler<'Exception>
              // separately serialize exception fields
  
negative.code:     type internal FsRecordPickler =
          
          static member Create<'Record>(resolver : IPicklerResolver) =
              if not <| typeof<'Record>.IsSerializable then
                  raise <| new NonSerializableTypeException(typeof<'Record>)
  
              let fields = FSharpType.GetRecordFields(typeof<'Record>, allMembers)
              let ctor = FSharpValue.PreComputeRecordConstructorInfo(typeof<'Record>, allMembers)
  