diff --git a/sprout/algorithm/fixed/merge.hpp b/sprout/algorithm/fixed/merge.hpp
index 771d84d3..5e4c644e 100644
--- a/sprout/algorithm/fixed/merge.hpp
+++ b/sprout/algorithm/fixed/merge.hpp
@@ -6,10 +6,11 @@
 #include <sprout/container/traits.hpp>
 #include <sprout/container/functions.hpp>
 #include <sprout/iterator/operation.hpp>
+#include <sprout/iterator/merge_iterator.hpp>
+#include <sprout/functional/less.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit.hpp>
 #include <sprout/detail/container_complate.hpp>
-#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
 
 namespace sprout {
 	namespace fixed {
@@ -67,6 +68,43 @@ namespace sprout {
 					: sprout::detail::container_complate(result, args...)
 					;
 			}
+
+			template<typename InputIterator1, typename InputIterator2, typename Result, typename Compare>
+			inline SPROUT_CONSTEXPR typename std::enable_if<
+				sprout::is_fixed_container<Result>::value,
+				typename sprout::fixed::result_of::algorithm<Result>::type
+			>::type
+			merge(
+				InputIterator1 first1, InputIterator1 last1,
+				InputIterator2 first2, InputIterator2 last2,
+				Result const& result, Compare comp
+				)
+			{
+				return sprout::fixed::detail::merge_impl(
+					first1, last1,
+					first2, last2,
+					result, comp,
+					sprout::size(result)
+					);
+			}
+
+			template<typename InputIterator1, typename InputIterator2, typename Result, typename Compare>
+			inline SPROUT_CONSTEXPR typename std::enable_if<
+				!sprout::is_fixed_container<Result>::value,
+				typename sprout::fixed::result_of::algorithm<Result>::type
+			>::type
+			merge(
+				InputIterator1 first1, InputIterator1 last1,
+				InputIterator2 first2, InputIterator2 last2,
+				Result const& result, Compare comp
+				)
+			{
+				return sprout::remake<Result>(
+					result, sprout::size(result),
+					sprout::make_merge_iterator(first1, last1, first2, last2, comp),
+					sprout::make_merge_iterator(last1, last1, last2, last2, comp)
+					);
+			}
 		}	// namespace detail
 		//
 		// merge
@@ -79,12 +117,7 @@ namespace sprout {
 			Result const& result, Compare comp
 			)
 		{
-			return sprout::fixed::detail::merge_impl(
-				first1, last1,
-				first2, last2,
-				result, comp,
-				sprout::size(result)
-				);
+			return sprout::fixed::detail::merge(first1, last1, first2, last2, result, comp);
 		}
 		template<typename InputIterator1, typename InputIterator2, typename Result>
 		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
@@ -94,12 +127,7 @@ namespace sprout {
 			Result const& result
 			)
 		{
-			return sprout::fixed::detail::merge_impl(
-				first1, last1,
-				first2, last2,
-				result, NS_SSCRISK_CEL_OR_SPROUT::less<typename sprout::container_traits<Result>::value_type>(),
-				sprout::size(result)
-				);
+			return sprout::fixed::merge(first1, last1, first2, last2, result, sprout::less<>());
 		}
 
 		template<typename Result, typename InputIterator1, typename InputIterator2, typename Compare>
diff --git a/sprout/algorithm/fixed/set_difference.hpp b/sprout/algorithm/fixed/set_difference.hpp
index df2713fd..b25365ec 100644
--- a/sprout/algorithm/fixed/set_difference.hpp
+++ b/sprout/algorithm/fixed/set_difference.hpp
@@ -6,10 +6,10 @@
 #include <sprout/container/traits.hpp>
 #include <sprout/container/functions.hpp>
 #include <sprout/iterator/operation.hpp>
+#include <sprout/functional/less.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit.hpp>
 #include <sprout/detail/container_complate.hpp>
-#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
 
 namespace sprout {
 	namespace fixed {
@@ -72,6 +72,25 @@ namespace sprout {
 					: sprout::detail::container_complate(result, args...)
 					;
 			}
+
+			template<typename InputIterator1, typename InputIterator2, typename Result, typename Compare>
+			inline SPROUT_CONSTEXPR typename std::enable_if<
+				sprout::is_fixed_container<Result>::value,
+				typename sprout::fixed::result_of::algorithm<Result>::type
+			>::type
+			set_difference(
+				InputIterator1 first1, InputIterator1 last1,
+				InputIterator2 first2, InputIterator2 last2,
+				Result const& result, Compare comp
+				)
+			{
+				return sprout::fixed::detail::set_difference_impl(
+					first1, last1,
+					first2, last2,
+					result, comp,
+					sprout::size(result)
+					);
+			}
 		}	// namespace detail
 		//
 		// set_difference
@@ -84,12 +103,7 @@ namespace sprout {
 			Result const& result, Compare comp
 			)
 		{
-			return sprout::fixed::detail::set_difference_impl(
-				first1, last1,
-				first2, last2,
-				result, comp,
-				sprout::size(result)
-				);
+			return sprout::fixed::detail::set_difference(first1, last1, first2, last2, result, comp);
 		}
 		template<typename InputIterator1, typename InputIterator2, typename Result>
 		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
@@ -99,12 +113,7 @@ namespace sprout {
 			Result const& result
 			)
 		{
-			return sprout::fixed::detail::set_difference_impl(
-				first1, last1,
-				first2, last2,
-				result, NS_SSCRISK_CEL_OR_SPROUT::less<typename sprout::container_traits<Result>::value_type>(),
-				sprout::size(result)
-				);
+			return sprout::fixed::set_difference(first1, last1, first2, last2, result, sprout::less<>());
 		}
 
 		template<typename Result, typename InputIterator1, typename InputIterator2, typename Compare>
diff --git a/sprout/algorithm/fixed/set_intersection.hpp b/sprout/algorithm/fixed/set_intersection.hpp
index b81e4a3b..8567d35e 100644
--- a/sprout/algorithm/fixed/set_intersection.hpp
+++ b/sprout/algorithm/fixed/set_intersection.hpp
@@ -6,10 +6,10 @@
 #include <sprout/container/traits.hpp>
 #include <sprout/container/functions.hpp>
 #include <sprout/iterator/operation.hpp>
+#include <sprout/functional/less.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit.hpp>
 #include <sprout/detail/container_complate.hpp>
-#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
 
 namespace sprout {
 	namespace fixed {
@@ -72,6 +72,25 @@ namespace sprout {
 					: sprout::detail::container_complate(result, args...)
 					;
 			}
+
+			template<typename InputIterator1, typename InputIterator2, typename Result, typename Compare>
+			inline SPROUT_CONSTEXPR typename std::enable_if<
+				sprout::is_fixed_container<Result>::value,
+				typename sprout::fixed::result_of::algorithm<Result>::type
+			>::type
+			set_intersection(
+				InputIterator1 first1, InputIterator1 last1,
+				InputIterator2 first2, InputIterator2 last2,
+				Result const& result, Compare comp
+				)
+			{
+				return sprout::fixed::detail::set_intersection_impl(
+					first1, last1,
+					first2, last2,
+					result, comp,
+					sprout::size(result)
+					);
+			}
 		}	// namespace detail
 		//
 		// set_intersection
@@ -84,12 +103,7 @@ namespace sprout {
 			Result const& result, Compare comp
 			)
 		{
-			return sprout::fixed::detail::set_intersection_impl(
-				first1, last1,
-				first2, last2,
-				result, comp,
-				sprout::size(result)
-				);
+			return sprout::fixed::detail::set_intersection(first1, last1, first2, last2, result, comp);
 		}
 		template<typename InputIterator1, typename InputIterator2, typename Result>
 		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
@@ -99,12 +113,7 @@ namespace sprout {
 			Result const& result
 			)
 		{
-			return sprout::fixed::detail::set_intersection_impl(
-				first1, last1,
-				first2, last2,
-				result, NS_SSCRISK_CEL_OR_SPROUT::less<typename sprout::container_traits<Result>::value_type>(),
-				sprout::size(result)
-				);
+			return sprout::fixed::set_intersection(first1, last1, first2, last2, result, sprout::less<>());
 		}
 
 		template<typename Result, typename InputIterator1, typename InputIterator2, typename Compare>
diff --git a/sprout/algorithm/fixed/set_symmetric_difference.hpp b/sprout/algorithm/fixed/set_symmetric_difference.hpp
index 46105b61..a95dcbcd 100644
--- a/sprout/algorithm/fixed/set_symmetric_difference.hpp
+++ b/sprout/algorithm/fixed/set_symmetric_difference.hpp
@@ -6,10 +6,10 @@
 #include <sprout/container/traits.hpp>
 #include <sprout/container/functions.hpp>
 #include <sprout/iterator/operation.hpp>
+#include <sprout/functional/less.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit.hpp>
 #include <sprout/detail/container_complate.hpp>
-#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
 
 namespace sprout {
 	namespace fixed {
@@ -72,6 +72,25 @@ namespace sprout {
 					: sprout::detail::container_complate(result, args...)
 					;
 			}
+
+			template<typename InputIterator1, typename InputIterator2, typename Result, typename Compare>
+			inline SPROUT_CONSTEXPR typename std::enable_if<
+				sprout::is_fixed_container<Result>::value,
+				typename sprout::fixed::result_of::algorithm<Result>::type
+			>::type
+			set_symmetric_difference(
+				InputIterator1 first1, InputIterator1 last1,
+				InputIterator2 first2, InputIterator2 last2,
+				Result const& result, Compare comp
+				)
+			{
+				return sprout::fixed::detail::set_symmetric_difference_impl(
+					first1, last1,
+					first2, last2,
+					result, comp,
+					sprout::size(result)
+					);
+			}
 		}	// namespace detail
 		//
 		// set_symmetric_difference
@@ -84,12 +103,7 @@ namespace sprout {
 			Result const& result, Compare comp
 			)
 		{
-			return sprout::fixed::detail::set_symmetric_difference_impl(
-				first1, last1,
-				first2, last2,
-				result, comp,
-				sprout::size(result)
-				);
+			return sprout::fixed::detail::set_symmetric_difference(first1, last1, first2, last2, result, comp);
 		}
 		template<typename InputIterator1, typename InputIterator2, typename Result>
 		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
@@ -99,12 +113,7 @@ namespace sprout {
 			Result const& result
 			)
 		{
-			return sprout::fixed::detail::set_symmetric_difference_impl(
-				first1, last1,
-				first2, last2,
-				result, NS_SSCRISK_CEL_OR_SPROUT::less<typename sprout::container_traits<Result>::value_type>(),
-				sprout::size(result)
-				);
+			return sprout::fixed::set_symmetric_difference(first1, last1, first2, last2, result, sprout::less<>());
 		}
 
 		template<typename Result, typename InputIterator1, typename InputIterator2, typename Compare>
diff --git a/sprout/algorithm/fixed/set_union.hpp b/sprout/algorithm/fixed/set_union.hpp
index 9a33646d..23cbd695 100644
--- a/sprout/algorithm/fixed/set_union.hpp
+++ b/sprout/algorithm/fixed/set_union.hpp
@@ -6,10 +6,11 @@
 #include <sprout/container/traits.hpp>
 #include <sprout/container/functions.hpp>
 #include <sprout/iterator/operation.hpp>
+#include <sprout/iterator/set_union_iterator.hpp>
+#include <sprout/functional/less.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit.hpp>
 #include <sprout/detail/container_complate.hpp>
-#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
 
 namespace sprout {
 	namespace fixed {
@@ -72,6 +73,43 @@ namespace sprout {
 					: sprout::detail::container_complate(result, args...)
 					;
 			}
+
+			template<typename InputIterator1, typename InputIterator2, typename Result, typename Compare>
+			inline SPROUT_CONSTEXPR typename std::enable_if<
+				sprout::is_fixed_container<Result>::value,
+				typename sprout::fixed::result_of::algorithm<Result>::type
+			>::type
+			set_union(
+				InputIterator1 first1, InputIterator1 last1,
+				InputIterator2 first2, InputIterator2 last2,
+				Result const& result, Compare comp
+				)
+			{
+				return sprout::fixed::detail::set_union_impl(
+					first1, last1,
+					first2, last2,
+					result, comp,
+					sprout::size(result)
+					);
+			}
+
+			template<typename InputIterator1, typename InputIterator2, typename Result, typename Compare>
+			inline SPROUT_CONSTEXPR typename std::enable_if<
+				!sprout::is_fixed_container<Result>::value,
+				typename sprout::fixed::result_of::algorithm<Result>::type
+			>::type
+			set_union(
+				InputIterator1 first1, InputIterator1 last1,
+				InputIterator2 first2, InputIterator2 last2,
+				Result const& result, Compare comp
+				)
+			{
+				return sprout::remake<Result>(
+					result, sprout::size(result),
+					sprout::make_set_union_iterator(first1, last1, first2, last2, comp),
+					sprout::make_set_union_iterator(last1, last1, last2, last2, comp)
+					);
+			}
 		}	// namespace detail
 		//
 		// set_union
@@ -84,12 +122,7 @@ namespace sprout {
 			Result const& result, Compare comp
 			)
 		{
-			return sprout::fixed::detail::set_union_impl(
-				first1, last1,
-				first2, last2,
-				result, comp,
-				sprout::size(result)
-				);
+			return sprout::fixed::detail::set_union(first1, last1, first2, last2, result, comp);
 		}
 		template<typename InputIterator1, typename InputIterator2, typename Result>
 		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
@@ -99,12 +132,7 @@ namespace sprout {
 			Result const& result
 			)
 		{
-			return sprout::fixed::detail::set_union_impl(
-				first1, last1,
-				first2, last2,
-				result, NS_SSCRISK_CEL_OR_SPROUT::less<typename sprout::container_traits<Result>::value_type>(),
-				sprout::size(result)
-				);
+			return sprout::fixed::set_union(first1, last1, first2, last2, result, sprout::less<>());
 		}
 
 		template<typename Result, typename InputIterator1, typename InputIterator2, typename Compare>
diff --git a/sprout/algorithm/fixed/unique_copy.hpp b/sprout/algorithm/fixed/unique_copy.hpp
index b38ccf87..a61e1f5c 100644
--- a/sprout/algorithm/fixed/unique_copy.hpp
+++ b/sprout/algorithm/fixed/unique_copy.hpp
@@ -61,6 +61,12 @@ namespace sprout {
 				;
 		}
 
+		template<typename Result, typename InputIterator>
+		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+		unique_copy(InputIterator first, InputIterator last) {
+			return sprout::fixed::unique_copy(first, last, sprout::pit<Result>());
+		}
+
 		namespace detail {
 			template<typename InputIterator, typename Result, typename BinaryPredicate, typename Head, typename... Args>
 			inline SPROUT_CONSTEXPR typename std::enable_if<
diff --git a/sprout/array/tuple.hpp b/sprout/array/tuple.hpp
index 652f48f9..c732d309 100644
--- a/sprout/array/tuple.hpp
+++ b/sprout/array/tuple.hpp
@@ -50,8 +50,8 @@ namespace std {
 	//
 	template<std::size_t I, typename T, std::size_t N>
 	struct tuple_element<I, sprout::array<T, N> > {
-	public:
 		static_assert(I < N, "tuple_element<>: index out of range");
+	public:
 		typedef T type;
 	};
 #if defined(__clang__)
diff --git a/sprout/index_tuple.hpp b/sprout/index_tuple.hpp
index f7e8b228..19bc2b92 100644
--- a/sprout/index_tuple.hpp
+++ b/sprout/index_tuple.hpp
@@ -3,6 +3,7 @@
 
 #include <sprout/config.hpp>
 #include <sprout/index_tuple/index_tuple.hpp>
+#include <sprout/index_tuple/tuple.hpp>
 #include <sprout/index_tuple/make_indexes.hpp>
 #include <sprout/index_tuple/index_range.hpp>
 #include <sprout/index_tuple/index_n.hpp>
diff --git a/sprout/index_tuple/detail/make_indexes_helper.hpp b/sprout/index_tuple/detail/make_indexes_helper.hpp
index 30604190..37c48f9d 100644
--- a/sprout/index_tuple/detail/make_indexes_helper.hpp
+++ b/sprout/index_tuple/detail/make_indexes_helper.hpp
@@ -6,7 +6,9 @@
 namespace sprout {
 	namespace detail {
 		template<typename IndexTupleType>
-		struct make_indexes_helper {
+		struct make_indexes_helper
+			: public IndexTupleType::type
+		{
 		public:
 			typedef typename IndexTupleType::type type;
 		public:
diff --git a/sprout/index_tuple/index_n.hpp b/sprout/index_tuple/index_n.hpp
index 32424971..cf284bf8 100644
--- a/sprout/index_tuple/index_n.hpp
+++ b/sprout/index_tuple/index_n.hpp
@@ -32,8 +32,7 @@ namespace sprout {
 		struct index_n_impl;
 		template<sprout::index_t I, std::size_t N>
 		struct index_n_impl<
-			I,
-			N,
+			I, N,
 			typename std::enable_if<(N == 0)>::type
 		> {
 		public:
@@ -41,8 +40,7 @@ namespace sprout {
 		};
 		template<sprout::index_t I, std::size_t N>
 		struct index_n_impl<
-			I,
-			N,
+			I, N,
 			typename std::enable_if<(N == 1)>::type
 		> {
 		public:
@@ -50,8 +48,7 @@ namespace sprout {
 		};
 		template<sprout::index_t I, std::size_t N>
 		struct index_n_impl<
-			I,
-			N,
+			I, N,
 			typename std::enable_if<(N > 1 && N % 2 == 0)>::type
 		>
 			: public sprout::detail::index_n_next<
@@ -60,8 +57,7 @@ namespace sprout {
 		{};
 		template<sprout::index_t I, std::size_t N>
 		struct index_n_impl<
-			I,
-			N,
+			I, N,
 			typename std::enable_if<(N > 1 && N % 2 == 1)>::type
 		>
 			: public sprout::detail::index_n_next2<
diff --git a/sprout/index_tuple/index_range.hpp b/sprout/index_tuple/index_range.hpp
index d7cc57b4..4fb1c63b 100644
--- a/sprout/index_tuple/index_range.hpp
+++ b/sprout/index_tuple/index_range.hpp
@@ -32,9 +32,7 @@ namespace sprout {
 		struct index_range_impl;
 		template<sprout::index_t First, sprout::index_t Step, std::size_t N>
 		struct index_range_impl<
-			First,
-			Step,
-			N,
+			First, Step, N,
 			typename std::enable_if<(N == 0)>::type
 		> {
 		public:
@@ -42,9 +40,7 @@ namespace sprout {
 		};
 		template<sprout::index_t First, sprout::index_t Step, std::size_t N>
 		struct index_range_impl<
-			First,
-			Step,
-			N,
+			First, Step, N,
 			typename std::enable_if<(N == 1)>::type
 		> {
 		public:
@@ -52,9 +48,7 @@ namespace sprout {
 		};
 		template<sprout::index_t First, sprout::index_t Step, std::size_t N>
 		struct index_range_impl<
-			First,
-			Step,
-			N,
+			First, Step, N,
 			typename std::enable_if<(N > 1 && N % 2 == 0)>::type
 		>
 			: public sprout::detail::index_range_next<
@@ -64,9 +58,7 @@ namespace sprout {
 		{};
 		template<sprout::index_t First, sprout::index_t Step, std::size_t N>
 		struct index_range_impl<
-			First,
-			Step,
-			N,
+			First, Step, N,
 			typename std::enable_if<(N > 1 && N % 2 == 1)>::type
 		>
 			: public sprout::detail::index_range_next2<
@@ -80,9 +72,7 @@ namespace sprout {
 	struct index_range
 		: public sprout::detail::make_indexes_helper<
 			sprout::detail::index_range_impl<
-				First,
-				Step,
-				((Last - First) + (Step - 1)) / Step
+				First, Step, ((Last - First) + (Step - 1)) / Step
 			>
 		>
 	{};
diff --git a/sprout/index_tuple/index_tuple.hpp b/sprout/index_tuple/index_tuple.hpp
index 0afcc9b3..69138ef3 100644
--- a/sprout/index_tuple/index_tuple.hpp
+++ b/sprout/index_tuple/index_tuple.hpp
@@ -17,7 +17,12 @@ namespace sprout {
 	struct index_tuple {
 	public:
 		typedef index_tuple type;
+		typedef sprout::index_t value_type;
+	public:
+		SPROUT_STATIC_CONSTEXPR std::size_t size = sizeof...(Indexes);
 	};
+	template<sprout::index_t... Indexes>
+	SPROUT_CONSTEXPR_OR_CONST std::size_t sprout::index_tuple<Indexes...>::size;
 }	// namespace sprout
 
 #endif	// #ifndef SPROUT_INDEX_TUPLE_INDEX_TUPLE_HPP
diff --git a/sprout/index_tuple/pack_indexes.hpp b/sprout/index_tuple/pack_indexes.hpp
index 57f92947..a6e6bfa1 100644
--- a/sprout/index_tuple/pack_indexes.hpp
+++ b/sprout/index_tuple/pack_indexes.hpp
@@ -2,6 +2,7 @@
 #define SPROUT_INDEX_TUPLE_PACK_INDEXES_HPP
 
 #include <sprout/config.hpp>
+#include <sprout/index_tuple/index_range.hpp>
 #include <sprout/index_tuple/detail/make_indexes_helper.hpp>
 
 namespace sprout {
diff --git a/sprout/index_tuple/tuple.hpp b/sprout/index_tuple/tuple.hpp
new file mode 100644
index 00000000..99c3456d
--- /dev/null
+++ b/sprout/index_tuple/tuple.hpp
@@ -0,0 +1,37 @@
+#ifndef SPROUT_INDEX_TUPLE_TUPLE_HPP
+#define SPROUT_INDEX_TUPLE_TUPLE_HPP
+
+#include <cstddef>
+#include <tuple>
+#include <type_traits>
+#include <sprout/config.hpp>
+#include <sprout/index_tuple/index_tuple.hpp>
+
+namespace std {
+#if defined(__clang__)
+#	pragma clang diagnostic push
+#	pragma clang diagnostic ignored "-Wmismatched-tags"
+#endif
+	//
+	// tuple_size
+	//
+	template<sprout::index_t... Indexes>
+	struct tuple_size<sprout::index_tuple<Indexes...> >
+		: public std::integral_constant<std::size_t, sizeof...(Indexes)>
+	{};
+
+	//
+	// tuple_element
+	//
+	template<std::size_t I, sprout::index_t... Indexes>
+	struct tuple_element<I, sprout::index_tuple<Indexes...> > {
+		static_assert(I < sizeof...(Indexes), "tuple_element<>: index out of range");
+	public:
+		typedef sprout::index_t type;
+	};
+#if defined(__clang__)
+#	pragma clang diagnostic pop
+#endif
+}	// namespace std
+
+#endif	// #ifndef SPROUT_INDEX_TUPLE_TUPLE_HPP
diff --git a/sprout/iterator/adaptor.hpp b/sprout/iterator/adaptor.hpp
index b4f40618..307feb18 100644
--- a/sprout/iterator/adaptor.hpp
+++ b/sprout/iterator/adaptor.hpp
@@ -15,6 +15,7 @@
 #include <sprout/iterator/valued_iterator.hpp>
 #include <sprout/iterator/joint_iterator.hpp>
 #include <sprout/iterator/alternate_iterator.hpp>
+#include <sprout/iterator/merge_iterator.hpp>
 #include <sprout/iterator/size_enum_iterator.hpp>
 #include <sprout/iterator/bytes_iterator.hpp>
 #include <sprout/iterator/remake_iterator.hpp>
diff --git a/sprout/iterator/alternate_iterator.hpp b/sprout/iterator/alternate_iterator.hpp
index 6607d12b..279d4f59 100644
--- a/sprout/iterator/alternate_iterator.hpp
+++ b/sprout/iterator/alternate_iterator.hpp
@@ -11,7 +11,6 @@
 #include <sprout/iterator/type_traits/common.hpp>
 #include <sprout/utility/swap.hpp>
 #include <sprout/utility/limited.hpp>
-#include <sprout/iterator/operation.hpp>
 
 namespace sprout {
 	//
diff --git a/sprout/iterator/merge_iterator.hpp b/sprout/iterator/merge_iterator.hpp
new file mode 100644
index 00000000..8aaf2cc4
--- /dev/null
+++ b/sprout/iterator/merge_iterator.hpp
@@ -0,0 +1,241 @@
+#ifndef SPROUT_ITERATOR_MERGE_ITERATOR_HPP
+#define SPROUT_ITERATOR_MERGE_ITERATOR_HPP
+
+#include <iterator>
+#include <utility>
+#include <type_traits>
+#include <sprout/config.hpp>
+#include <sprout/iterator/next.hpp>
+#include <sprout/iterator/type_traits/common.hpp>
+#include <sprout/utility/swap.hpp>
+
+namespace sprout {
+	//
+	// merge_iterator
+	//
+	template<
+		typename LIterator, typename RIterator,
+		typename Compare = sprout::less<>
+	>
+	class merge_iterator
+		: public std::iterator<
+			typename sprout::min_iterator_category<
+				typename sprout::common_iterator_category<LIterator, RIterator>::type,
+				std::forward_iterator_tag
+			>::type,
+			typename sprout::common_iterator_value_type<LIterator, RIterator>::type,
+			typename sprout::common_iterator_difference_type<LIterator, RIterator>::type,
+			typename sprout::common_iterator_pointer<LIterator, RIterator>::type,
+			typename sprout::common_iterator_reference<LIterator, RIterator>::type
+		>
+	{
+	public:
+		typedef LIterator iterator_type;
+		typedef RIterator iterator2_type;
+		typedef Compare compare_type;
+		typedef typename sprout::min_iterator_category<
+			typename sprout::common_iterator_category<LIterator, RIterator>::type,
+			std::forward_iterator_tag
+		>::type iterator_category;
+		typedef typename sprout::common_iterator_value_type<LIterator, RIterator>::type value_type;
+		typedef typename sprout::common_iterator_difference_type<LIterator, RIterator>::type difference_type;
+		typedef typename sprout::common_iterator_pointer<LIterator, RIterator>::type pointer;
+		typedef typename sprout::common_iterator_reference<LIterator, RIterator>::type reference;
+	private:
+		static SPROUT_CONSTEXPR bool check_in_left(
+			iterator_type it1, iterator_type lst1,
+			iterator2_type it2, iterator2_type lst2,
+			Compare comp
+			)
+		{
+			return it1 != lst1 ? (it2 != lst2 ? !comp(*it2, *it1) : true)
+				: !(it2 != lst2)
+				;
+		}
+	protected:
+		iterator_type current1;
+		iterator_type lst1;
+		iterator2_type current2;
+		iterator2_type lst2;
+		Compare comp;
+		bool in_left;
+	public:
+		merge_iterator()
+			: current1(), lst1(), current2(), lst2(), comp(), in_left(true)
+		{}
+		merge_iterator(merge_iterator const&) = default;
+		SPROUT_CONSTEXPR merge_iterator(
+			iterator_type it1, iterator_type lst1,
+			iterator2_type it2, iterator2_type lst2,
+			Compare comp = Compare()
+			)
+			: current1(it1), lst1(lst1)
+			, current2(it2), lst2(lst2)
+			, comp(comp)
+			, in_left(check_in_left(it1, lst1, it2, lst2, comp))
+		{}
+		template<typename U, typename V, typename W>
+		SPROUT_CONSTEXPR merge_iterator(merge_iterator<U, V, W> const& it)
+			: current1(it.base()), lst1(it.last1())
+			, current2(it.base2()), lst2(it.last2())
+			, comp(it.compare())
+			, in_left(it.is_in_left())
+		{}
+		template<typename U, typename V, typename W>
+		merge_iterator& operator=(merge_iterator<U, V, W> const& it) {
+			merge_iterator temp(it);
+			temp.swap(*this);
+			return *this;
+		}
+		SPROUT_CONSTEXPR iterator_type base() const {
+			return current1;
+		}
+		SPROUT_CONSTEXPR iterator_type last1() const {
+			return lst1;
+		}
+		SPROUT_CONSTEXPR iterator2_type base2() const {
+			return current2;
+		}
+		SPROUT_CONSTEXPR iterator2_type last2() const {
+			return lst2;
+		}
+		SPROUT_CONSTEXPR Compare compare() const {
+			return comp;
+		}
+		SPROUT_CONSTEXPR bool is_in_left() const {
+			return in_left;
+		}
+		SPROUT_CONSTEXPR reference operator*() const {
+			return is_in_left() ? *current1 : *current2;
+		}
+		SPROUT_CONSTEXPR pointer operator->() const {
+			return &*(*this);
+		}
+		merge_iterator& operator++() {
+			if (current1 != lst1) {
+				if (current2 != lst2) {
+					if (comp(*current2, *current1)) {
+						++current2;
+					} else {
+						++current1;
+					}
+				} else {
+					++current1;
+				}
+			} else if (current2 != lst2) {
+				++current2;
+			}
+			in_left = check_in_left(current1, lst1, current2, lst2, comp);
+			return *this;
+		}
+		merge_iterator operator++(int) {
+			merge_iterator result(*this);
+			if (current1 != lst1) {
+				if (current2 != lst2) {
+					if (comp(*current2, *current1)) {
+						++current2;
+					} else {
+						++current1;
+					}
+				} else {
+					++current1;
+				}
+			} else if (current2 != lst2) {
+				++current2;
+			}
+			in_left = check_in_left(current1, lst1, current2, lst2, comp);
+			return result;
+		}
+		SPROUT_CONSTEXPR merge_iterator next() const {
+			return current1 != lst1
+				? current2 != lst2
+					? comp(*current2, *current1)
+						? merge_iterator(current1, lst1, sprout::next(current2), lst2, comp)
+						: merge_iterator(sprout::next(current1), lst1, current2, lst2, comp)
+					: merge_iterator(sprout::next(current1), lst1, current2, lst2, comp)
+				: current2 != lst2
+					? merge_iterator(current1, lst1, sprout::next(current2), lst2, comp)
+				: *this
+				;
+		}
+		void swap(merge_iterator& other)
+		SPROUT_NOEXCEPT_EXPR(
+			SPROUT_NOEXCEPT_EXPR(sprout::swap(current1, other.current1))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(lst1, other.lst1))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(current2, other.current2))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(lst2, other.lst2))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(comp, other.comp))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(in_left, other.in_left))
+			)
+		{
+			sprout::swap(current1, other.current1);
+			sprout::swap(lst1, other.lst1);
+			sprout::swap(current2, other.current2);
+			sprout::swap(lst2, other.lst2);
+			sprout::swap(comp, other.comp);
+			sprout::swap(in_left, other.in_left);
+		}
+	};
+
+	template<
+		typename LIterator1, typename RIterator1, typename Compare1,
+		typename LIterator2, typename RIterator2, typename Compare2
+	>
+	inline SPROUT_CONSTEXPR bool operator==(
+		sprout::merge_iterator<LIterator1, RIterator1, Compare1> const& lhs,
+		sprout::merge_iterator<LIterator2, RIterator2, Compare2> const& rhs
+		)
+	{
+		return lhs.base() == rhs.base() && lhs.base2() == rhs.base2();
+	}
+	template<
+		typename LIterator1, typename RIterator1, typename Compare1,
+		typename LIterator2, typename RIterator2, typename Compare2
+	>
+	inline SPROUT_CONSTEXPR bool operator!=(
+		sprout::merge_iterator<LIterator1, RIterator1, Compare1> const& lhs,
+		sprout::merge_iterator<LIterator2, RIterator2, Compare2> const& rhs
+		)
+	{
+		return !(lhs == rhs);
+	}
+
+	//
+	// make_merge_iterator
+	//
+	template<typename LIterator, typename RIterator, typename Compare>
+	inline SPROUT_CONSTEXPR sprout::merge_iterator<LIterator, RIterator, Compare>
+	make_merge_iterator(LIterator it1, LIterator lst1, RIterator it2, RIterator lst2, Compare comp) {
+		return sprout::merge_iterator<LIterator, RIterator, Compare>(it1, lst1, it2, lst2, comp);
+	}
+	template<typename LIterator, typename RIterator>
+	inline SPROUT_CONSTEXPR sprout::merge_iterator<LIterator, RIterator>
+	make_merge_iterator(LIterator it1, LIterator lst1, RIterator it2, RIterator lst2) {
+		return sprout::merge_iterator<LIterator, RIterator>(it1, lst1, it2, lst2);
+	}
+
+	//
+	// swap
+	//
+	template<typename LIterator, typename RIterator, typename Compare>
+	inline void
+	swap(
+		sprout::merge_iterator<LIterator, RIterator, Compare>& lhs,
+		sprout::merge_iterator<LIterator, RIterator, Compare>& rhs
+		)
+	SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(lhs.swap(rhs)))
+	{
+		lhs.swap(rhs);
+	}
+
+	//
+	// iterator_next
+	//
+	template<typename LIterator, typename RIterator, typename Compare>
+	inline SPROUT_CONSTEXPR sprout::merge_iterator<LIterator, RIterator, Compare>
+	iterator_next(sprout::merge_iterator<LIterator, RIterator, Compare> const& it) {
+		return it.next();
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_ITERATOR_MERGE_ITERATOR_HPP
diff --git a/sprout/iterator/set_union_iterator.hpp b/sprout/iterator/set_union_iterator.hpp
new file mode 100644
index 00000000..a8bc3967
--- /dev/null
+++ b/sprout/iterator/set_union_iterator.hpp
@@ -0,0 +1,249 @@
+#ifndef SPROUT_ITERATOR_SET_UNION_ITERATOR_HPP
+#define SPROUT_ITERATOR_SET_UNION_ITERATOR_HPP
+
+#include <iterator>
+#include <utility>
+#include <type_traits>
+#include <sprout/config.hpp>
+#include <sprout/iterator/next.hpp>
+#include <sprout/iterator/type_traits/common.hpp>
+#include <sprout/utility/swap.hpp>
+
+namespace sprout {
+	//
+	// set_union_iterator
+	//
+	template<
+		typename LIterator, typename RIterator,
+		typename Compare = sprout::less<>
+	>
+	class set_union_iterator
+		: public std::iterator<
+			typename sprout::min_iterator_category<
+				typename sprout::common_iterator_category<LIterator, RIterator>::type,
+				std::forward_iterator_tag
+			>::type,
+			typename sprout::common_iterator_value_type<LIterator, RIterator>::type,
+			typename sprout::common_iterator_difference_type<LIterator, RIterator>::type,
+			typename sprout::common_iterator_pointer<LIterator, RIterator>::type,
+			typename sprout::common_iterator_reference<LIterator, RIterator>::type
+		>
+	{
+	public:
+		typedef LIterator iterator_type;
+		typedef RIterator iterator2_type;
+		typedef Compare compare_type;
+		typedef typename sprout::min_iterator_category<
+			typename sprout::common_iterator_category<LIterator, RIterator>::type,
+			std::forward_iterator_tag
+		>::type iterator_category;
+		typedef typename sprout::common_iterator_value_type<LIterator, RIterator>::type value_type;
+		typedef typename sprout::common_iterator_difference_type<LIterator, RIterator>::type difference_type;
+		typedef typename sprout::common_iterator_pointer<LIterator, RIterator>::type pointer;
+		typedef typename sprout::common_iterator_reference<LIterator, RIterator>::type reference;
+	private:
+		static SPROUT_CONSTEXPR bool check_in_left(
+			iterator_type it1, iterator_type lst1,
+			iterator2_type it2, iterator2_type lst2,
+			Compare comp
+			)
+		{
+			return it1 != lst1 ? (it2 != lst2 ? comp(*it1, *it2) || !comp(*it2, *it1) : true)
+				: !(it2 != lst2)
+				;
+		}
+	protected:
+		iterator_type current1;
+		iterator_type lst1;
+		iterator2_type current2;
+		iterator2_type lst2;
+		Compare comp;
+		bool in_left;
+	public:
+		set_union_iterator()
+			: current1(), lst1(), current2(), lst2(), comp(), in_left(true)
+		{}
+		set_union_iterator(set_union_iterator const&) = default;
+		SPROUT_CONSTEXPR set_union_iterator(
+			iterator_type it1, iterator_type lst1,
+			iterator2_type it2, iterator2_type lst2,
+			Compare comp = Compare()
+			)
+			: current1(it1), lst1(lst1)
+			, current2(it2), lst2(lst2)
+			, comp(comp)
+			, in_left(check_in_left(it1, lst1, it2, lst2, comp))
+		{}
+		template<typename U, typename V, typename W>
+		SPROUT_CONSTEXPR set_union_iterator(set_union_iterator<U, V, W> const& it)
+			: current1(it.base()), lst1(it.last1())
+			, current2(it.base2()), lst2(it.last2())
+			, comp(it.compare())
+			, in_left(it.is_in_left())
+		{}
+		template<typename U, typename V, typename W>
+		set_union_iterator& operator=(set_union_iterator<U, V, W> const& it) {
+			set_union_iterator temp(it);
+			temp.swap(*this);
+			return *this;
+		}
+		SPROUT_CONSTEXPR iterator_type base() const {
+			return current1;
+		}
+		SPROUT_CONSTEXPR iterator_type last1() const {
+			return lst1;
+		}
+		SPROUT_CONSTEXPR iterator2_type base2() const {
+			return current2;
+		}
+		SPROUT_CONSTEXPR iterator2_type last2() const {
+			return lst2;
+		}
+		SPROUT_CONSTEXPR Compare compare() const {
+			return comp;
+		}
+		SPROUT_CONSTEXPR bool is_in_left() const {
+			return in_left;
+		}
+		SPROUT_CONSTEXPR reference operator*() const {
+			return is_in_left() ? *current1 : *current2;
+		}
+		SPROUT_CONSTEXPR pointer operator->() const {
+			return &*(*this);
+		}
+		set_union_iterator& operator++() {
+			if (current1 != lst1) {
+				if (current2 != lst2) {
+					if (comp(*current1, *current2)) {
+						++current1;
+					} else if (comp(*current2, *current1)) {
+						++current2;
+					} else {
+						++current1;
+						++current2;
+					}
+				} else {
+					++current1;
+				}
+			} else if (current2 != lst2) {
+				++current2;
+			}
+			in_left = check_in_left(current1, lst1, current2, lst2, comp);
+			return *this;
+		}
+		set_union_iterator operator++(int) {
+			set_union_iterator result(*this);
+			if (current1 != lst1) {
+				if (current2 != lst2) {
+					if (comp(*current1, *current2)) {
+						++current1;
+					} else if (comp(*current2, *current1)) {
+						++current2;
+					} else {
+						++current1;
+						++current2;
+					}
+				} else {
+					++current1;
+				}
+			} else if (current2 != lst2) {
+				++current2;
+			}
+			in_left = check_in_left(current1, lst1, current2, lst2, comp);
+			return result;
+		}
+		SPROUT_CONSTEXPR set_union_iterator next() const {
+			return current1 != lst1
+				? current2 != lst2
+					? comp(*current1, *current2)
+						? set_union_iterator(sprout::next(current1), lst1, current2, lst2, comp)
+						: comp(*current2, *current1)
+							? set_union_iterator(current1, lst1, sprout::next(current2), lst2, comp)
+							: set_union_iterator(sprout::next(current1), lst1, sprout::next(current2), lst2, comp)
+					: set_union_iterator(sprout::next(current1), lst1, current2, lst2, comp)
+				: current2 != lst2
+					? set_union_iterator(current1, lst1, sprout::next(current2), lst2, comp)
+				: *this
+				;
+		}
+		void swap(set_union_iterator& other)
+		SPROUT_NOEXCEPT_EXPR(
+			SPROUT_NOEXCEPT_EXPR(sprout::swap(current1, other.current1))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(lst1, other.lst1))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(current2, other.current2))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(lst2, other.lst2))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(comp, other.comp))
+			&& SPROUT_NOEXCEPT_EXPR(sprout::swap(in_left, other.in_left))
+			)
+		{
+			sprout::swap(current1, other.current1);
+			sprout::swap(lst1, other.lst1);
+			sprout::swap(current2, other.current2);
+			sprout::swap(lst2, other.lst2);
+			sprout::swap(comp, other.comp);
+			sprout::swap(in_left, other.in_left);
+		}
+	};
+
+	template<
+		typename LIterator1, typename RIterator1, typename Compare1,
+		typename LIterator2, typename RIterator2, typename Compare2
+	>
+	inline SPROUT_CONSTEXPR bool operator==(
+		sprout::set_union_iterator<LIterator1, RIterator1, Compare1> const& lhs,
+		sprout::set_union_iterator<LIterator2, RIterator2, Compare2> const& rhs
+		)
+	{
+		return lhs.base() == rhs.base() && lhs.base2() == rhs.base2();
+	}
+	template<
+		typename LIterator1, typename RIterator1, typename Compare1,
+		typename LIterator2, typename RIterator2, typename Compare2
+	>
+	inline SPROUT_CONSTEXPR bool operator!=(
+		sprout::set_union_iterator<LIterator1, RIterator1, Compare1> const& lhs,
+		sprout::set_union_iterator<LIterator2, RIterator2, Compare2> const& rhs
+		)
+	{
+		return !(lhs == rhs);
+	}
+
+	//
+	// make_set_union_iterator
+	//
+	template<typename LIterator, typename RIterator, typename Compare>
+	inline SPROUT_CONSTEXPR sprout::set_union_iterator<LIterator, RIterator, Compare>
+	make_set_union_iterator(LIterator it1, LIterator lst1, RIterator it2, RIterator lst2, Compare comp) {
+		return sprout::set_union_iterator<LIterator, RIterator, Compare>(it1, lst1, it2, lst2, comp);
+	}
+	template<typename LIterator, typename RIterator>
+	inline SPROUT_CONSTEXPR sprout::set_union_iterator<LIterator, RIterator>
+	make_set_union_iterator(LIterator it1, LIterator lst1, RIterator it2, RIterator lst2) {
+		return sprout::set_union_iterator<LIterator, RIterator>(it1, lst1, it2, lst2);
+	}
+
+	//
+	// swap
+	//
+	template<typename LIterator, typename RIterator, typename Compare>
+	inline void
+	swap(
+		sprout::set_union_iterator<LIterator, RIterator, Compare>& lhs,
+		sprout::set_union_iterator<LIterator, RIterator, Compare>& rhs
+		)
+	SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(lhs.swap(rhs)))
+	{
+		lhs.swap(rhs);
+	}
+
+	//
+	// iterator_next
+	//
+	template<typename LIterator, typename RIterator, typename Compare>
+	inline SPROUT_CONSTEXPR sprout::set_union_iterator<LIterator, RIterator, Compare>
+	iterator_next(sprout::set_union_iterator<LIterator, RIterator, Compare> const& it) {
+		return it.next();
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_ITERATOR_SET_UNION_ITERATOR_HPP
diff --git a/sprout/numeric/fixed/adjacent_difference.hpp b/sprout/numeric/fixed/adjacent_difference.hpp
index c8e8cb56..81dcb373 100644
--- a/sprout/numeric/fixed/adjacent_difference.hpp
+++ b/sprout/numeric/fixed/adjacent_difference.hpp
@@ -7,6 +7,8 @@
 #include <sprout/container/functions.hpp>
 #include <sprout/iterator/operation.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
+#include <sprout/pit.hpp>
+#include <sprout/detail/container_complate.hpp>
 
 namespace sprout {
 	namespace fixed {
@@ -79,6 +81,12 @@ namespace sprout {
 			return sprout::fixed::detail::adjacent_difference_impl(first, last, result, sprout::size(result));
 		}
 
+		template<typename Result, typename InputIterator>
+		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+		adjacent_difference(InputIterator first, InputIterator last) {
+			return sprout::fixed::adjacent_difference(first, last, sprout::pit<Result>());
+		}
+
 		namespace detail {
 			template<typename InputIterator, typename Result, typename BinaryOperation, typename... Args>
 			inline SPROUT_CONSTEXPR typename std::enable_if<
@@ -147,6 +155,12 @@ namespace sprout {
 		adjacent_difference(InputIterator first, InputIterator last, Result const& result, BinaryOperation binary_op) {
 			return sprout::fixed::detail::adjacent_difference_impl(first, last, result, binary_op, sprout::size(result));
 		}
+
+		template<typename Result, typename InputIterator, typename BinaryOperation>
+		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+		adjacent_difference(InputIterator first, InputIterator last, BinaryOperation binary_op) {
+			return sprout::fixed::adjacent_difference(first, last, sprout::pit<Result>(), binary_op);
+		}
 	}	// namespace fixed
 
 	using sprout::fixed::adjacent_difference;
diff --git a/sprout/numeric/fixed/iota.hpp b/sprout/numeric/fixed/iota.hpp
index 992c81bf..c10f9acc 100644
--- a/sprout/numeric/fixed/iota.hpp
+++ b/sprout/numeric/fixed/iota.hpp
@@ -6,7 +6,9 @@
 #include <sprout/container/traits.hpp>
 #include <sprout/container/functions.hpp>
 #include <sprout/iterator/operation.hpp>
+#include <sprout/iterator/counting_iterator.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
+#include <sprout/pit.hpp>
 
 namespace sprout {
 	namespace fixed {
@@ -29,6 +31,33 @@ namespace sprout {
 						)...
 					);
 			}
+
+			template<typename Container, typename T>
+			inline SPROUT_CONSTEXPR typename std::enable_if<
+				sprout::is_fixed_container<Container>::value,
+				typename sprout::fixed::result_of::algorithm<Container>::type
+			>::type
+			iota(Container const& cont, T value) {
+				return sprout::fixed::detail::iota_impl(
+					cont, sprout::index_range<0, sprout::container_traits<Container>::static_size>::make(),
+					value,
+					sprout::internal_begin_offset(cont),
+					sprout::size(cont)
+					);
+			}
+
+			template<typename Container, typename T>
+			inline SPROUT_CONSTEXPR typename std::enable_if<
+				!sprout::is_fixed_container<Container>::value,
+				typename sprout::fixed::result_of::algorithm<Container>::type
+			>::type
+			iota(Container const& cont, T value) {
+				return sprout::remake<Container>(
+					cont, sprout::size(cont),
+					sprout::make_counting_iterator(value),
+					sprout::next(sprout::make_counting_iterator(value), sprout::size(cont))
+					);
+			}
 		}	// namespace detail
 		//
 		// iota
@@ -36,13 +65,13 @@ namespace sprout {
 		template<typename Container, typename T>
 		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Container>::type
 		iota(Container const& cont, T value) {
-			return sprout::fixed::detail::iota_impl(
-				cont,
-				sprout::index_range<0, sprout::container_traits<Container>::static_size>::make(),
-				value,
-				sprout::internal_begin_offset(cont),
-				sprout::size(cont)
-				);
+			return sprout::fixed::detail::iota(cont, value);
+		}
+
+		template<typename Container, typename T>
+		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Container>::type
+		iota(T value) {
+			return sprout::fixed::detail::iota(sprout::pit<Container>(), value);
 		}
 	}	// namespace fixed
 
diff --git a/sprout/numeric/fixed/partial_sum.hpp b/sprout/numeric/fixed/partial_sum.hpp
index b7396ee6..fe1680b0 100644
--- a/sprout/numeric/fixed/partial_sum.hpp
+++ b/sprout/numeric/fixed/partial_sum.hpp
@@ -7,6 +7,7 @@
 #include <sprout/container/functions.hpp>
 #include <sprout/iterator/operation.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
+#include <sprout/pit.hpp>
 #include <sprout/detail/container_complate.hpp>
 
 namespace sprout {
@@ -80,6 +81,12 @@ namespace sprout {
 			return sprout::fixed::detail::partial_sum_impl(first, last, result, sprout::size(result));
 		}
 
+		template<typename Result, typename InputIterator>
+		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+		partial_sum(InputIterator first, InputIterator last) {
+			return sprout::fixed::partial_sum(first, last, sprout::pit<Result>());
+		}
+
 		namespace detail {
 			template<typename InputIterator, typename Result, typename BinaryOperation, typename... Args>
 			inline SPROUT_CONSTEXPR typename std::enable_if<
@@ -148,6 +155,12 @@ namespace sprout {
 		partial_sum(InputIterator first, InputIterator last, Result const& result, BinaryOperation binary_op) {
 			return sprout::fixed::detail::partial_sum_impl(first, last, result, binary_op, sprout::size(result));
 		}
+
+		template<typename Result, typename InputIterator, typename BinaryOperation>
+		inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+		partial_sum(InputIterator first, InputIterator last, BinaryOperation binary_op) {
+			return sprout::fixed::partial_sum(first, last, sprout::pit<Result>(), binary_op);
+		}
 	}	// namespace fixed
 
 	using sprout::fixed::partial_sum;
diff --git a/sprout/range/algorithm/fixed/clamp_range_copy.hpp b/sprout/range/algorithm/fixed/clamp_range_copy.hpp
index 302004a8..1b153e16 100644
--- a/sprout/range/algorithm/fixed/clamp_range_copy.hpp
+++ b/sprout/range/algorithm/fixed/clamp_range_copy.hpp
@@ -34,6 +34,28 @@ namespace sprout {
 			{
 				return sprout::fixed::clamp_range_copy(sprout::begin(input), sprout::end(input), result, low, high);
 			}
+
+			template<typename Result, typename Input, typename Compare>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			clamp_range_copy(
+				Input const& input,
+				typename sprout::container_traits<Input>::value_type const& low,
+				typename sprout::container_traits<Input>::value_type const& high,
+				Compare comp
+				)
+			{
+				return sprout::fixed::clamp_range_copy<Result>(sprout::begin(input), sprout::end(input), low, high, comp);
+			}
+			template<typename Result, typename Input>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			clamp_range_copy(
+				Input const& input,
+				typename sprout::container_traits<Input>::value_type const& low,
+				typename sprout::container_traits<Input>::value_type const& high
+				)
+			{
+				return sprout::fixed::clamp_range_copy<Result>(sprout::begin(input), sprout::end(input), low, high);
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::clamp_range_copy;
diff --git a/sprout/range/algorithm/fixed/copy_until.hpp b/sprout/range/algorithm/fixed/copy_until.hpp
index f7e59c27..0ef743a6 100644
--- a/sprout/range/algorithm/fixed/copy_until.hpp
+++ b/sprout/range/algorithm/fixed/copy_until.hpp
@@ -18,6 +18,12 @@ namespace sprout {
 			copy_until(Input const& input, Result const& result, Predicate pred) {
 				return sprout::fixed::copy_until(sprout::begin(input), sprout::end(input), result);
 			}
+
+			template<typename Result, typename Input, typename Predicate>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			copy_until(Input const& input, Predicate pred) {
+				return sprout::fixed::copy_until<Result>(sprout::begin(input), sprout::end(input));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::copy_until;
diff --git a/sprout/range/algorithm/fixed/copy_while.hpp b/sprout/range/algorithm/fixed/copy_while.hpp
index 373d0eeb..648e0e25 100644
--- a/sprout/range/algorithm/fixed/copy_while.hpp
+++ b/sprout/range/algorithm/fixed/copy_while.hpp
@@ -18,6 +18,12 @@ namespace sprout {
 			copy_while(Input const& input, Result const& result, Predicate pred) {
 				return sprout::fixed::copy_while(sprout::begin(input), sprout::end(input), result);
 			}
+
+			template<typename Result, typename Input, typename Predicate>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			copy_while(Input const& input, Predicate pred) {
+				return sprout::fixed::copy_while<Result>(sprout::begin(input), sprout::end(input));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::copy_while;
diff --git a/sprout/range/algorithm/fixed/merge.hpp b/sprout/range/algorithm/fixed/merge.hpp
index 7831bbcc..71324f6c 100644
--- a/sprout/range/algorithm/fixed/merge.hpp
+++ b/sprout/range/algorithm/fixed/merge.hpp
@@ -23,6 +23,17 @@ namespace sprout {
 			merge(Input1 const& input1, Input2 const& input2, Result const& result) {
 				return sprout::fixed::merge(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), result);
 			}
+
+			template<typename Result, typename Input1, typename Input2, typename Compare>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			merge(Input1 const& input1, Input2 const& input2, Compare comp) {
+				return sprout::fixed::merge<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), comp);
+			}
+			template<typename Result, typename Input1, typename Input2>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			merge(Input1 const& input1, Input2 const& input2) {
+				return sprout::fixed::merge<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::merge;
diff --git a/sprout/range/algorithm/fixed/partition_copy.hpp b/sprout/range/algorithm/fixed/partition_copy.hpp
index 8a72442d..32dcda75 100644
--- a/sprout/range/algorithm/fixed/partition_copy.hpp
+++ b/sprout/range/algorithm/fixed/partition_copy.hpp
@@ -18,6 +18,12 @@ namespace sprout {
 			partition_copy(Input const& input, Result const& result, Predicate pred) {
 				return sprout::fixed::partition_copy(sprout::begin(input), sprout::end(input), result, pred);
 			}
+
+			template<typename Result, typename Input, typename Predicate>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			partition_copy(Input const& input, Predicate pred) {
+				return sprout::fixed::partition_copy<Result>(sprout::begin(input), sprout::end(input), pred);
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::partition_copy;
diff --git a/sprout/range/algorithm/fixed/remove_copy.hpp b/sprout/range/algorithm/fixed/remove_copy.hpp
index 7bfce123..c8a526e2 100644
--- a/sprout/range/algorithm/fixed/remove_copy.hpp
+++ b/sprout/range/algorithm/fixed/remove_copy.hpp
@@ -18,6 +18,12 @@ namespace sprout {
 			remove_copy(Input const& input, Result const& result, T const& value) {
 				return sprout::fixed::remove_copy(sprout::begin(input), sprout::end(input), result, value);
 			}
+
+			template<typename Result, typename Input, typename T>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			remove_copy(Input const& input, Result const& result, T const& value) {
+				return sprout::fixed::remove_copy<Result>(sprout::begin(input), sprout::end(input), value);
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::remove_copy;
diff --git a/sprout/range/algorithm/fixed/remove_copy_if.hpp b/sprout/range/algorithm/fixed/remove_copy_if.hpp
index eb6be178..babaf8d8 100644
--- a/sprout/range/algorithm/fixed/remove_copy_if.hpp
+++ b/sprout/range/algorithm/fixed/remove_copy_if.hpp
@@ -18,6 +18,12 @@ namespace sprout {
 			remove_copy_if(Input const& input, Result const& result, Predicate pred) {
 				return sprout::fixed::remove_copy_if(sprout::begin(input), sprout::end(input), result, pred);
 			}
+
+			template<typename Result, typename Input, typename Predicate>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			remove_copy_if(Input const& input, Predicate pred) {
+				return sprout::fixed::remove_copy_if<Result>(sprout::begin(input), sprout::end(input), pred);
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::remove_copy_if;
diff --git a/sprout/range/algorithm/fixed/reverse_copy.hpp b/sprout/range/algorithm/fixed/reverse_copy.hpp
index 7bd8e4e5..3c1f0326 100644
--- a/sprout/range/algorithm/fixed/reverse_copy.hpp
+++ b/sprout/range/algorithm/fixed/reverse_copy.hpp
@@ -18,6 +18,12 @@ namespace sprout {
 			reverse_copy(Input const& input, Result const& result) {
 				return sprout::fixed::reverse_copy(sprout::begin(input), sprout::end(input), result);
 			}
+
+			template<typename Result, typename Input>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			reverse_copy(Input const& input) {
+				return sprout::fixed::reverse_copy<Result>(sprout::begin(input), sprout::end(input));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::reverse_copy;
diff --git a/sprout/range/algorithm/fixed/rotate_copy.hpp b/sprout/range/algorithm/fixed/rotate_copy.hpp
index e52e1055..3188c669 100644
--- a/sprout/range/algorithm/fixed/rotate_copy.hpp
+++ b/sprout/range/algorithm/fixed/rotate_copy.hpp
@@ -22,6 +22,15 @@ namespace sprout {
 			{
 				return sprout::fixed::rotate_copy(sprout::begin(input), middle, sprout::end(input), result);
 			}
+
+			template<typename Result, typename Input>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			rotate_copy(
+				Input const& input, typename sprout::container_traits<Input>::const_iterator middle
+				)
+			{
+				return sprout::fixed::rotate_copy<Result>(sprout::begin(input), middle, sprout::end(input));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::rotate_copy;
diff --git a/sprout/range/algorithm/fixed/set_difference.hpp b/sprout/range/algorithm/fixed/set_difference.hpp
index 1f832230..53d4784e 100644
--- a/sprout/range/algorithm/fixed/set_difference.hpp
+++ b/sprout/range/algorithm/fixed/set_difference.hpp
@@ -23,6 +23,17 @@ namespace sprout {
 			set_difference(Input1 const& input1, Input2 const& input2, Result const& result) {
 				return sprout::fixed::set_difference(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), result);
 			}
+
+			template<typename Result, typename Input1, typename Input2, typename Compare>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			set_difference(Input1 const& input1, Input2 const& input2, Compare comp) {
+				return sprout::fixed::set_difference<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), comp);
+			}
+			template<typename Result, typename Input1, typename Input2>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			set_difference(Input1 const& input1, Input2 const& input2) {
+				return sprout::fixed::set_difference<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::set_difference;
diff --git a/sprout/range/algorithm/fixed/set_intersection.hpp b/sprout/range/algorithm/fixed/set_intersection.hpp
index cd945756..bb39974d 100644
--- a/sprout/range/algorithm/fixed/set_intersection.hpp
+++ b/sprout/range/algorithm/fixed/set_intersection.hpp
@@ -23,6 +23,17 @@ namespace sprout {
 			set_intersection(Input1 const& input1, Input2 const& input2, Result const& result) {
 				return sprout::fixed::set_intersection(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), result);
 			}
+
+			template<typename Result, typename Input1, typename Input2, typename Compare>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			set_intersection(Input1 const& input1, Input2 const& input2, Compare comp) {
+				return sprout::fixed::set_intersection<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), comp);
+			}
+			template<typename Result, typename Input1, typename Input2>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			set_intersection(Input1 const& input1, Input2 const& input2) {
+				return sprout::fixed::set_intersection<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::set_intersection;
diff --git a/sprout/range/algorithm/fixed/set_symmetric_difference.hpp b/sprout/range/algorithm/fixed/set_symmetric_difference.hpp
index 5691e8c2..0b0854c3 100644
--- a/sprout/range/algorithm/fixed/set_symmetric_difference.hpp
+++ b/sprout/range/algorithm/fixed/set_symmetric_difference.hpp
@@ -23,6 +23,17 @@ namespace sprout {
 			set_symmetric_difference(Input1 const& input1, Input2 const& input2, Result const& result) {
 				return sprout::fixed::set_symmetric_difference(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), result);
 			}
+
+			template<typename Result, typename Input1, typename Input2, typename Compare>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			set_symmetric_difference(Input1 const& input1, Input2 const& input2, Compare comp) {
+				return sprout::fixed::set_symmetric_difference<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), comp);
+			}
+			template<typename Result, typename Input1, typename Input2>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			set_symmetric_difference(Input1 const& input1, Input2 const& input2) {
+				return sprout::fixed::set_symmetric_difference<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::set_symmetric_difference;
diff --git a/sprout/range/algorithm/fixed/set_union.hpp b/sprout/range/algorithm/fixed/set_union.hpp
index b9a42a00..934ea49c 100644
--- a/sprout/range/algorithm/fixed/set_union.hpp
+++ b/sprout/range/algorithm/fixed/set_union.hpp
@@ -23,6 +23,17 @@ namespace sprout {
 			set_union(Input1 const& input1, Input2 const& input2, Result const& result) {
 				return sprout::fixed::set_union(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), result);
 			}
+
+			template<typename Result, typename Input1, typename Input2, typename Compare>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			set_union(Input1 const& input1, Input2 const& input2, Compare comp) {
+				return sprout::fixed::set_union<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2), comp);
+			}
+			template<typename Result, typename Input1, typename Input2>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			set_union(Input1 const& input1, Input2 const& input2) {
+				return sprout::fixed::set_union<Result>(sprout::begin(input1), sprout::end(input1), sprout::begin(input2), sprout::end(input2));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::set_union;
diff --git a/sprout/range/algorithm/fixed/stable_partition_copy.hpp b/sprout/range/algorithm/fixed/stable_partition_copy.hpp
index beaa5c46..9810838a 100644
--- a/sprout/range/algorithm/fixed/stable_partition_copy.hpp
+++ b/sprout/range/algorithm/fixed/stable_partition_copy.hpp
@@ -18,6 +18,12 @@ namespace sprout {
 			stable_partition_copy(Input const& input, Result const& result, Predicate pred) {
 				return sprout::fixed::stable_partition_copy(sprout::begin(input), sprout::end(input), result, pred);
 			}
+
+			template<typename Result, typename Input, typename Predicate>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			stable_partition_copy(Input const& input, Predicate pred) {
+				return sprout::fixed::stable_partition_copy<Result>(sprout::begin(input), sprout::end(input), pred);
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::stable_partition_copy;
diff --git a/sprout/range/algorithm/fixed/swap_element_copy.hpp b/sprout/range/algorithm/fixed/swap_element_copy.hpp
index 84e09d33..93a01fd1 100644
--- a/sprout/range/algorithm/fixed/swap_element_copy.hpp
+++ b/sprout/range/algorithm/fixed/swap_element_copy.hpp
@@ -23,6 +23,17 @@ namespace sprout {
 			{
 				return sprout::fixed::swap_element_copy(sprout::begin(input), sprout::end(input), result, pos1, pos2);
 			}
+
+			template<typename Result, typename Input>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			swap_element_copy(
+				Input const& input,
+				typename sprout::container_traits<Input>::const_iterator pos1,
+				typename sprout::container_traits<Input>::const_iterator pos2
+				)
+			{
+				return sprout::fixed::swap_element_copy<Result>(sprout::begin(input), sprout::end(input), pos1, pos2);
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::swap_element_copy;
diff --git a/sprout/range/algorithm/fixed/unique_copy.hpp b/sprout/range/algorithm/fixed/unique_copy.hpp
index 240b42ba..72854457 100644
--- a/sprout/range/algorithm/fixed/unique_copy.hpp
+++ b/sprout/range/algorithm/fixed/unique_copy.hpp
@@ -23,6 +23,17 @@ namespace sprout {
 			unique_copy(Input const& input, Result const& result) {
 				return sprout::fixed::unique_copy(sprout::begin(input), sprout::end(input), result);
 			}
+
+			template<typename Result, typename Input, typename BinaryPredicate>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			unique_copy(Input const& input, BinaryPredicate pred) {
+				return sprout::fixed::unique_copy<Result>(sprout::begin(input), sprout::end(input), pred);
+			}
+			template<typename Result, typename Input>
+			inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+			unique_copy(Input const& input) {
+				return sprout::fixed::unique_copy<Result>(sprout::begin(input), sprout::end(input));
+			}
 		}	// namespace fixed
 
 		using sprout::range::fixed::unique_copy;
diff --git a/sprout/string/tuple.hpp b/sprout/string/tuple.hpp
index c0581e4f..10cf7e92 100644
--- a/sprout/string/tuple.hpp
+++ b/sprout/string/tuple.hpp
@@ -50,8 +50,8 @@ namespace std {
 	//
 	template<std::size_t I, typename T, std::size_t N, typename Traits>
 	struct tuple_element<I, sprout::basic_string<T, N, Traits> > {
-	public:
 		static_assert(I < N, "tuple_element<>: index out of range");
+	public:
 		typedef T type;
 	};
 #if defined(__clang__)
diff --git a/sprout/type/integral_array.hpp b/sprout/type/integral_array.hpp
index 779d6824..5d78e797 100644
--- a/sprout/type/integral_array.hpp
+++ b/sprout/type/integral_array.hpp
@@ -18,6 +18,7 @@ namespace sprout {
 			: public sprout::types::type_tuple<std::integral_constant<T, Values>...>
 		{
 		public:
+			typedef integral_array type;
 			typedef T value_type;
 		};
 	}	// namespace types
diff --git a/sprout/type/string/string.hpp b/sprout/type/string/string.hpp
index fd7aea59..884263c6 100644
--- a/sprout/type/string/string.hpp
+++ b/sprout/type/string/string.hpp
@@ -15,7 +15,10 @@ namespace sprout {
 		template<typename T, T... Values>
 		struct basic_string
 			: public sprout::types::integral_array<T, Values...>
-		{};
+		{
+		public:
+			typedef basic_string type;
+		};
 	}	// namespace types
 }	// namespace sprout
 
diff --git a/sprout/type/type_tuple.hpp b/sprout/type/type_tuple.hpp
index a065ccc4..24ce84c8 100644
--- a/sprout/type/type_tuple.hpp
+++ b/sprout/type/type_tuple.hpp
@@ -18,9 +18,14 @@ namespace sprout {
 		template<typename... Types>
 		struct type_tuple {
 		public:
+			typedef type_tuple type;
 			typedef sprout::types::index_iterator<type_tuple, 0> begin;
 			typedef sprout::types::index_iterator<type_tuple, sizeof...(Types)> end;
+		public:
+			SPROUT_STATIC_CONSTEXPR std::size_t size = sizeof...(Types);
 		};
+		template<typename... Types>
+		SPROUT_CONSTEXPR_OR_CONST std::size_t sprout::types::type_tuple<Types...>::size;
 
 		//
 		// rebind_types
diff --git a/sprout/uuid/tuple.hpp b/sprout/uuid/tuple.hpp
index 99301db3..cdc9d0f1 100644
--- a/sprout/uuid/tuple.hpp
+++ b/sprout/uuid/tuple.hpp
@@ -52,8 +52,8 @@ namespace std {
 	//
 	template<std::size_t I>
 	struct tuple_element<I, sprout::uuids::uuid> {
-	public:
 		static_assert(I < 16, "tuple_element<>: index out of range");
+	public:
 		typedef sprout::uuids::uuid::value_type type;
 	};
 #if defined(__clang__)