diff --git a/sprout/cstdlib/abs.hpp b/sprout/cstdlib/abs.hpp
index a40cf775..e164bf2a 100644
--- a/sprout/cstdlib/abs.hpp
+++ b/sprout/cstdlib/abs.hpp
@@ -29,24 +29,26 @@ namespace sprout {
 		return sprout::llabs(j);
 	}
 
-	template<
-		typename IntType,
-		typename sprout::enabler_if<
-			std::is_integral<IntType>::value && std::is_signed<IntType>::value
-		>::type = sprout::enabler
-	>
-	SPROUT_CONSTEXPR IntType abs(IntType j) {
-		return j < 0 ? -j : j;
-	}
-	template<
-		typename IntType,
-		typename sprout::enabler_if<
-			std::is_integral<IntType>::value && std::is_unsigned<IntType>::value
-		>::type = sprout::enabler
-	>
-	SPROUT_CONSTEXPR IntType abs(IntType j) {
-		return j;
-	}
+	namespace {
+		template<
+			typename IntType,
+			typename sprout::enabler_if<
+				std::is_integral<IntType>::value && std::is_signed<IntType>::value
+			>::type = sprout::enabler
+		>
+		SPROUT_CONSTEXPR IntType abs(IntType j) {
+			return j < 0 ? -j : j;
+		}
+		template<
+			typename IntType,
+			typename sprout::enabler_if<
+				std::is_integral<IntType>::value && std::is_unsigned<IntType>::value
+			>::type = sprout::enabler
+		>
+		SPROUT_CONSTEXPR IntType abs(IntType j) {
+			return j;
+		}
+	}	// anonymous-namespace
 }	// namespace sprout
 
 #endif	// #ifndef SPROUT_CSTDLIB_ABS_HPP
diff --git a/sprout/string/alias.hpp b/sprout/string/alias.hpp
index d9fd74e4..9344530d 100644
--- a/sprout/string/alias.hpp
+++ b/sprout/string/alias.hpp
@@ -2,7 +2,6 @@
 #define SPROUT_STRING_ALIAS_HPP
 
 #include <sprout/config.hpp>
-
 #if SPROUT_USE_TEMPLATE_ALIASES
 #	include <cstddef>
 #	include <sprout/string/string.hpp>
diff --git a/sprout/type_traits.hpp b/sprout/type_traits.hpp
index 621e9d11..c3f54d4e 100644
--- a/sprout/type_traits.hpp
+++ b/sprout/type_traits.hpp
@@ -8,6 +8,9 @@
 #include <sprout/type_traits/is_c_str.hpp>
 #include <sprout/type_traits/lvalue_reference.hpp>
 #include <sprout/type_traits/const_reference.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
 #include <sprout/type_traits/has_xxx.hpp>
+#include <sprout/type_traits/inherit_if_xxx.hpp>
+#include <sprout/type_traits/aliases.hpp>
 
 #endif	// #ifndef SPROUT_TYPE_TRAITS_HPP
diff --git a/sprout/type_traits/aliases.hpp b/sprout/type_traits/aliases.hpp
new file mode 100644
index 00000000..9e1384d0
--- /dev/null
+++ b/sprout/type_traits/aliases.hpp
@@ -0,0 +1,91 @@
+#ifndef SPROUT_TYPE_TRAITS_ALIASES_HPP
+#define SPROUT_TYPE_TRAITS_ALIASES_HPP
+
+#include <sprout/config.hpp>
+
+#if SPROUT_USE_TEMPLATE_ALIASES
+#	include <cstddef>
+#	include <type_traits>
+#endif	// #if SPROUT_USE_TEMPLATE_ALIASES
+
+namespace sprout {
+#if SPROUT_USE_TEMPLATE_ALIASES
+	// Copyright (c) 2011 osyo-manga : http://d.hatena.ne.jp/osyo-manga/
+
+	//
+	// Const-volatility specifiers
+	//
+	template<typename T>
+	using remove_const_ = typename std::remove_const<T>::type;
+	template<typename T>
+	using remove_volatile_ = typename std::remove_volatile<T>::type;
+	template<typename T>
+	using remove_cv_ = typename std::remove_cv<T>::type;
+	template<typename T>
+	using add_const_ = typename std::add_const<T>::type;
+	template<typename T>
+	using add_volatile_ = typename std::add_volatile<T>::type;
+	template<typename T>
+	using add_cv_ = typename std::add_cv<T>::type;
+
+	//
+	// References
+	//
+	template<typename T>
+	using remove_reference_ = typename std::remove_reference<T>::type;
+	template<typename T>
+	using add_lvalue_reference_ = typename std::add_lvalue_reference<T>::type;
+	template<typename T>
+	using add_rvalue_reference_ = typename std::add_rvalue_reference<T>::type;
+
+	//
+	// Pointers
+	//
+	template<typename T>
+	using remove_pointer_ = typename std::remove_pointer<T>::type;
+	template<typename T>
+	using add_pointer_ = typename std::add_pointer<T>::type;
+
+	//
+	// Sign modifiers
+	//
+	template<typename T>
+	using make_signed_ = typename std::make_signed<T>::type;
+	template<typename T>
+	using make_unsigned_ = typename std::make_unsigned<T>::type;
+
+	//
+	// Arrays
+	//
+	template<typename T>
+	using remove_extent_ = typename std::remove_extent<T>::type;
+	template<typename T>
+	using remove_all_extents_ = typename std::remove_all_extents<T>::type;
+
+	//
+	// Miscellaneous transformations
+	//
+	template<
+		std::size_t Len,
+		std::size_t Align = std::alignment_of<typename std::aligned_storage<Len>::type>::value
+	>
+	using aligned_storage_ = typename std::aligned_storage<Len, Align>::type;
+	// !!!
+	//template<std::size_t Len, typename... Types>
+	//using aligned_union_ = typename std::aligned_union<Len, Types...>::type;
+	template<typename T>
+	using decay_ = typename std::decay<T>::type;
+	template<bool B, typename T = void>
+	using enable_if_ = typename std::enable_if<B, T>::type;
+	template<bool B, typename T, typename F>
+	using conditional_ = typename std::conditional<B, T, F>::type;
+	template<typename... Types>
+	using common_type_ = typename std::common_type<Types...>::type;
+	template<typename T>
+	using underlying_type_ = typename std::underlying_type<T>::type;
+	template<typename F, typename... ArgTypes>
+	using result_of_ = typename std::result_of<F(ArgTypes...)>::type;
+#endif	// #if SPROUT_USE_TEMPLATE_ALIASES
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_TYPE_TRAITS_ALIASES_HPP
diff --git a/sprout/type_traits/const_reference.hpp b/sprout/type_traits/const_reference.hpp
index ecb17aa5..04f5db58 100644
--- a/sprout/type_traits/const_reference.hpp
+++ b/sprout/type_traits/const_reference.hpp
@@ -14,6 +14,11 @@ namespace sprout {
 	public:
 		typedef decltype(sprout::as_const(std::declval<T&&>())) type;
 	};
+
+#if SPROUT_USE_TEMPLATE_ALIASES
+	template<typename T>
+	using const_reference_ = typename sprout::const_reference<T>::type;
+#endif	// #if SPROUT_USE_TEMPLATE_ALIASES
 }	// namespace sprout
 
 #endif	// #ifndef SPROUT_TYPE_TRAITS_CONST_REFERENCE_HPP
diff --git a/sprout/type_traits/enabler_if.hpp b/sprout/type_traits/enabler_if.hpp
new file mode 100644
index 00000000..a2b388c3
--- /dev/null
+++ b/sprout/type_traits/enabler_if.hpp
@@ -0,0 +1,28 @@
+#ifndef SPROUT_TYPE_TRAITS_ENABLER_IF_HPP
+#define SPROUT_TYPE_TRAITS_ENABLER_IF_HPP
+
+#include <type_traits>
+#include <sprout/config.hpp>
+
+namespace sprout {
+	//
+	// enabler_t
+	// enabler
+	//
+	typedef void* enabler_t;
+	extern enabler_t enabler;
+	//
+	// enabler_if
+	//
+	template<bool C>
+	class enabler_if
+		: public std::enable_if<C, sprout::enabler_t&>
+	{};
+
+#if SPROUT_USE_TEMPLATE_ALIASES
+	template<bool C>
+	using enabler_if_ = typename sprout::enabler_if<C>::type;
+#endif	// #if SPROUT_USE_TEMPLATE_ALIASES
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_TYPE_TRAITS_ENABLER_IF_HPP
diff --git a/sprout/type_traits/lvalue_reference.hpp b/sprout/type_traits/lvalue_reference.hpp
index 7a0b1c62..40e879df 100644
--- a/sprout/type_traits/lvalue_reference.hpp
+++ b/sprout/type_traits/lvalue_reference.hpp
@@ -14,6 +14,11 @@ namespace sprout {
 	public:
 		typedef decltype(sprout::as_lvalue(std::declval<T&&>())) type;
 	};
+
+#if SPROUT_USE_TEMPLATE_ALIASES
+	template<typename T>
+	using lvalue_reference_ = typename sprout::lvalue_reference<T>::type;
+#endif	// #if SPROUT_USE_TEMPLATE_ALIASES
 }	// namespace sprout
 
 #endif	// #ifndef SPROUT_TYPE_TRAITS_LVALUE_REFERENCE_HPP
diff --git a/sprout/utility/enabler_if.hpp b/sprout/utility/enabler_if.hpp
index db0e4580..6525bf32 100644
--- a/sprout/utility/enabler_if.hpp
+++ b/sprout/utility/enabler_if.hpp
@@ -1,23 +1,7 @@
 #ifndef SPROUT_UTILITY_ENABLER_IF_HPP
 #define SPROUT_UTILITY_ENABLER_IF_HPP
 
-#include <type_traits>
 #include <sprout/config.hpp>
-
-namespace sprout {
-	//
-	// enabler_t
-	// enabler
-	//
-	typedef void* enabler_t;
-	extern enabler_t enabler;
-	//
-	// enabler_if
-	//
-	template<bool C>
-	class enabler_if
-		: public std::enable_if<C, enabler_t&>
-	{};
-}	// namespace sprout
+#include <sprout/type_traits/enabler_if.hpp>
 
 #endif	// #ifndef SPROUT_UTILITY_ENABLER_IF_HPP