diff --git a/include/rapidjson/internal/meta.h b/include/rapidjson/internal/meta.h
index 0861a48..5b9a8c0 100644
--- a/include/rapidjson/internal/meta.h
+++ b/include/rapidjson/internal/meta.h
@@ -24,11 +24,11 @@ struct SelectIf : SelectIfCond<Condition::Value,T1,T2> {};
 template <bool Constify, typename T>
 struct MaybeAddConst : SelectIfCond<Constify, const T, T> {};
 
-template <typename T, typename U> struct IsSame { enum { Value = false }; };
-template <typename T> struct IsSame<T,T> { enum { Value = true }; };
+template <typename T, typename U> struct IsSame  : FalseType {};
+template <typename T> struct IsSame<T,T>  : TrueType {};
 
-template <typename T> struct IsConst { enum { Value = false }; };
-template <typename T> struct IsConst<const T> { enum { Value = true }; };
+template <typename T> struct IsConst : FalseType {};
+template <typename T> struct IsConst<const T> : TrueType {};
 
 template <typename CT, typename T>
 struct IsMoreConst {