anchor.diff:      <@ "aaa".CompareTo(null) @> |> check ("aaa".CompareTo(null))
   
     [<Test>]
  +  let ``struct equals`` () =
  +    <@ Struct(1).Equals(Struct(1)) @> |> check (Struct(1).Equals(Struct(1)))
  +
  +  [<Test>]
     let ``value type get type code`` () =
       <@ (1).GetTypeCode() @> |> check ((1).GetTypeCode())
       <@ (true).GetTypeCode() @> |> check ((true).GetTypeCode())
  
positive.code:     <@ (box true).ToString() @> |> check ((box true).ToString())
      <@ (box 'a').ToString() @> |> check ((box 'a').ToString())
      <@ (box "aaa").ToString() @> |> check ((box "aaa").ToString())
  
    [<Test>]
    let ``value type get type`` () =
  
negative.code:     <@ (true).GetHashCode() @> |> check ((true).GetHashCode())
      <@ 'a'.GetHashCode() @> |> check ('a'.GetHashCode())
      <@ "aaa".GetHashCode() @> |> check ("aaa".GetHashCode())
      <@ Struct(1).GetHashCode() @> |> check (Struct(1).GetHashCode())
  