diff --git a/sprout/algorithm/copy.hpp b/sprout/algorithm/copy.hpp
index 34141412..eb158687 100644
--- a/sprout/algorithm/copy.hpp
+++ b/sprout/algorithm/copy.hpp
@@ -9,6 +9,43 @@
 #define SPROUT_ALGORITHM_COPY_HPP
 
 #include <sprout/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+#include <sprout/iterator/type_traits/is_iterator_of.hpp>
+#include <sprout/algorithm/fixed/result_of.hpp>
+#include <sprout/algorithm/fixed/copy.hpp>
+
+namespace sprout {
+	//
+	// 25.3.1 Copy
+	//
+	template<
+		typename InputIterator, typename OutputIterator,
+		typename sprout::enabler_if<sprout::is_output_iterator<OutputIterator>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CXX14_CONSTEXPR OutputIterator
+	copy(InputIterator first, InputIterator last, OutputIterator result) {
+		while (first != last) {
+			*result++ = *first++;
+		}
+		return result;
+	}
+
+	template<
+		typename InputIterator, typename Result,
+		typename sprout::enabler_if<!sprout::is_output_iterator<Result>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+	copy(InputIterator first, InputIterator last, Result const& result) {
+		return sprout::fixed::copy(first, last, result);
+	}
+
+	template<typename Result, typename InputIterator>
+	inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+	copy(InputIterator first, InputIterator last) {
+		return sprout::fixed::copy<Result>(first, last);
+	}
+}	// namespace sprout
+
 #include <sprout/algorithm/fixed/copy.hpp>
 #include <sprout/algorithm/fit/copy.hpp>
 
diff --git a/sprout/algorithm/copy_backward.hpp b/sprout/algorithm/copy_backward.hpp
index dcedeb4c..c2ce8a6f 100644
--- a/sprout/algorithm/copy_backward.hpp
+++ b/sprout/algorithm/copy_backward.hpp
@@ -9,6 +9,43 @@
 #define SPROUT_ALGORITHM_COPY_BACKWARD_HPP
 
 #include <sprout/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+#include <sprout/iterator/type_traits/is_iterator_of.hpp>
+#include <sprout/algorithm/fixed/result_of.hpp>
+#include <sprout/algorithm/fixed/copy_backward.hpp>
+
+namespace sprout {
+	//
+	// 25.3.1 Copy
+	//
+	template<
+		typename BidirectionalIterator1, typename BidirectionalIterator2,
+		typename sprout::enabler_if<sprout::is_output_iterator<BidirectionalIterator2>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CXX14_CONSTEXPR BidirectionalIterator2
+	copy_backward(BidirectionalIterator1 first, BidirectionalIterator1 last, BidirectionalIterator2 result) {
+		while (first != last) {
+			*--result = *--first;
+		}
+		return result;
+	}
+
+	template<
+		typename BidirectionalIterator, typename Result,
+		typename sprout::enabler_if<!sprout::is_output_iterator<Result>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+	copy_backward(BidirectionalIterator first, BidirectionalIterator last, Result const& result) {
+		return sprout::fixed::copy_backward(first, last, result);
+	}
+
+	template<typename Result, typename BidirectionalIterator>
+	inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+	copy_backward(BidirectionalIterator first, BidirectionalIterator last) {
+		return sprout::fixed::copy_backward<Result>(first, last);
+	}
+}	// namespace sprout
+
 #include <sprout/algorithm/fixed/copy_backward.hpp>
 #include <sprout/algorithm/fit/copy_backward.hpp>
 
diff --git a/sprout/algorithm/copy_if.hpp b/sprout/algorithm/copy_if.hpp
index 2cdf7af6..b5755da9 100644
--- a/sprout/algorithm/copy_if.hpp
+++ b/sprout/algorithm/copy_if.hpp
@@ -9,6 +9,45 @@
 #define SPROUT_ALGORITHM_COPY_IF_HPP
 
 #include <sprout/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+#include <sprout/iterator/type_traits/is_iterator_of.hpp>
+#include <sprout/algorithm/fixed/result_of.hpp>
+#include <sprout/algorithm/fixed/copy_if.hpp>
+
+namespace sprout {
+	//
+	// 25.3.1 Copy
+	//
+	template<
+		typename InputIterator, typename OutputIterator, typename Predicate,
+		typename sprout::enabler_if<sprout::is_output_iterator<OutputIterator>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CXX14_CONSTEXPR OutputIterator
+	copy_if(InputIterator first, InputIterator last, OutputIterator result, Predicate pred) {
+		for (; first != last; ++first) {
+			if (pred(*first)) {
+				*result++ = *first;
+			}
+		}
+		return result;
+	}
+
+	template<
+		typename InputIterator, typename Result, typename Predicate,
+		typename sprout::enabler_if<!sprout::is_output_iterator<Result>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+	copy_if(InputIterator first, InputIterator last, Result const& result, Predicate pred) {
+		return sprout::fixed::copy_if(first, last, result, pred);
+	}
+
+	template<typename Result, typename InputIterator, typename Predicate>
+	inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+	copy_if(InputIterator first, InputIterator last, Predicate pred) {
+		return sprout::fixed::copy_if<Result>(first, last, pred);
+	}
+}	// namespace sprout
+
 #include <sprout/algorithm/fixed/copy_if.hpp>
 #include <sprout/algorithm/fit/copy_if.hpp>
 
diff --git a/sprout/algorithm/copy_n.hpp b/sprout/algorithm/copy_n.hpp
index 1661bd79..86c415e8 100644
--- a/sprout/algorithm/copy_n.hpp
+++ b/sprout/algorithm/copy_n.hpp
@@ -9,6 +9,43 @@
 #define SPROUT_ALGORITHM_COPY_N_HPP
 
 #include <sprout/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+#include <sprout/iterator/type_traits/is_iterator_of.hpp>
+#include <sprout/algorithm/fixed/result_of.hpp>
+#include <sprout/algorithm/fixed/copy_n.hpp>
+
+namespace sprout {
+	//
+	// 25.3.1 Copy
+	//
+	template<
+		typename InputIterator, typename Size, typename OutputIterator,
+		typename sprout::enabler_if<sprout::is_output_iterator<OutputIterator>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CXX14_CONSTEXPR OutputIterator
+	copy_n(InputIterator first, Size n, OutputIterator result) {
+		for (Size i = 0; i < n; ++i) {
+			*result++ = *first++;
+		}
+		return result;
+	}
+
+	template<
+		typename InputIterator, typename Size, typename Result,
+		typename sprout::enabler_if<!sprout::is_output_iterator<Result>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+	copy_n(InputIterator first, Size n, Result const& result) {
+		return sprout::fixed::copy_n(first, n, result);
+	}
+
+	template<typename Result, typename Size, typename InputIterator>
+	inline SPROUT_CONSTEXPR typename sprout::fixed::result_of::algorithm<Result>::type
+	copy_n(InputIterator first, Size n) {
+		return sprout::fixed::copy_n<Result>(first, n);
+	}
+}	// namespace sprout
+
 #include <sprout/algorithm/fixed/copy_n.hpp>
 #include <sprout/algorithm/fit/copy_n.hpp>
 
diff --git a/sprout/algorithm/fixed/copy.hpp b/sprout/algorithm/fixed/copy.hpp
index 6f257c30..8045c483 100644
--- a/sprout/algorithm/fixed/copy.hpp
+++ b/sprout/algorithm/fixed/copy.hpp
@@ -134,8 +134,6 @@ namespace sprout {
 			return sprout::fixed::copy(first, last, sprout::pit<Result>());
 		}
 	}	// namespace fixed
-
-	using sprout::fixed::copy;
 }	// namespace sprout
 
 #endif	// #ifndef SPROUT_ALGORITHM_FIXED_COPY_HPP
diff --git a/sprout/algorithm/fixed/copy_backward.hpp b/sprout/algorithm/fixed/copy_backward.hpp
index a122f3bf..5603f685 100644
--- a/sprout/algorithm/fixed/copy_backward.hpp
+++ b/sprout/algorithm/fixed/copy_backward.hpp
@@ -124,8 +124,6 @@ namespace sprout {
 			return sprout::fixed::copy_backward(first, last, sprout::pit<Result>());
 		}
 	}	// namespace fixed
-
-	using sprout::fixed::copy_backward;
 }	// namespace sprout
 
 #endif	// #ifndef SPROUT_ALGORITHM_FIXED_COPY_BACKWARD_HPP
diff --git a/sprout/algorithm/fixed/copy_if.hpp b/sprout/algorithm/fixed/copy_if.hpp
index 37e9200a..4ca0cf88 100644
--- a/sprout/algorithm/fixed/copy_if.hpp
+++ b/sprout/algorithm/fixed/copy_if.hpp
@@ -89,8 +89,6 @@ namespace sprout {
 			return sprout::fixed::copy_if(first, last, sprout::pit<Result>(), pred);
 		}
 	}	// namespace fixed
-
-	using sprout::fixed::copy_if;
 }	// namespace sprout
 
 #endif	// #ifndef SPROUT_ALGORITHM_FIXED_COPY_IF_HPP
diff --git a/sprout/algorithm/fixed/copy_n.hpp b/sprout/algorithm/fixed/copy_n.hpp
index fcf32022..ae3c1711 100644
--- a/sprout/algorithm/fixed/copy_n.hpp
+++ b/sprout/algorithm/fixed/copy_n.hpp
@@ -107,8 +107,6 @@ namespace sprout {
 			return sprout::fixed::copy_n(first, n, sprout::pit<Result>());
 		}
 	}	// namespace fixed
-
-	using sprout::fixed::copy_n;
 }	// namespace sprout
 
 #endif	// #ifndef SPROUT_ALGORITHM_FIXED_COPY_N_HPP
diff --git a/sprout/algorithm/iter_swap.hpp b/sprout/algorithm/iter_swap.hpp
new file mode 100644
index 00000000..e0db022d
--- /dev/null
+++ b/sprout/algorithm/iter_swap.hpp
@@ -0,0 +1,25 @@
+/*=============================================================================
+  Copyright (c) 2011-2013 Bolero MURAKAMI
+  https://github.com/bolero-MURAKAMI/Sprout
+
+  Distributed under the Boost Software License, Version 1.0. (See accompanying
+  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+=============================================================================*/
+#ifndef SPROUT_ALGORITHM_ITER_SWAP_HPP
+#define SPROUT_ALGORITHM_ITER_SWAP_HPP
+
+#include <sprout/config.hpp>
+#include <sprout/utility/swap.hpp>
+
+namespace sprout {
+	//
+	// 25.3.3 swap
+	//
+	template<typename ForwardIterator1, typename ForwardIterator2>
+	inline SPROUT_CXX14_CONSTEXPR void
+	iter_swap(ForwardIterator1 a, ForwardIterator2 b) {
+		sprout::swap(*a, *b);
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_ALGORITHM_ITER_SWAP_HPP
diff --git a/sprout/algorithm/modifying.hpp b/sprout/algorithm/modifying.hpp
index 1e2a459c..552c952d 100644
--- a/sprout/algorithm/modifying.hpp
+++ b/sprout/algorithm/modifying.hpp
@@ -9,7 +9,71 @@
 #define SPROUT_ALGORITHM_MODIFYIING_HPP
 
 #include <sprout/config.hpp>
-#include <sprout/algorithm/fixed.hpp>
-#include <sprout/algorithm/fit.hpp>
+#include <sprout/algorithm/copy.hpp>
+#include <sprout/algorithm/copy_n.hpp>
+#include <sprout/algorithm/copy_if.hpp>
+#include <sprout/algorithm/copy_backward.hpp>
+#include <sprout/algorithm/move.hpp>
+#include <sprout/algorithm/move_backward.hpp>
+#include <sprout/algorithm/swap_ranges.hpp>
+#include <sprout/algorithm/iter_swap.hpp>
+#include <sprout/algorithm/transform.hpp>
+#include <sprout/algorithm/replace.hpp>
+#include <sprout/algorithm/replace_if.hpp>
+#include <sprout/algorithm/replace_copy.hpp>
+#include <sprout/algorithm/replace_copy_if.hpp>
+#include <sprout/algorithm/fill.hpp>
+#include <sprout/algorithm/fill_n.hpp>
+#include <sprout/algorithm/generate.hpp>
+#include <sprout/algorithm/generate_n.hpp>
+#include <sprout/algorithm/unfold.hpp>
+#include <sprout/algorithm/unfold_n.hpp>
+#include <sprout/algorithm/recurrence.hpp>
+#include <sprout/algorithm/recurrence_n.hpp>
+#include <sprout/algorithm/remove.hpp>
+#include <sprout/algorithm/remove_if.hpp>
+#include <sprout/algorithm/remove_copy.hpp>
+#include <sprout/algorithm/remove_copy_if.hpp>
+#include <sprout/algorithm/unique.hpp>
+#include <sprout/algorithm/unique_copy.hpp>
+#include <sprout/algorithm/reverse.hpp>
+#include <sprout/algorithm/reverse_copy.hpp>
+#include <sprout/algorithm/rotate.hpp>
+#include <sprout/algorithm/rotate_copy.hpp>
+#include <sprout/algorithm/shuffle.hpp>
+#include <sprout/algorithm/shuffle_result.hpp>
+#include <sprout/algorithm/partition.hpp>
+#include <sprout/algorithm/partition_copy.hpp>
+#include <sprout/algorithm/stable_partition.hpp>
+#include <sprout/algorithm/stable_partition_copy.hpp>
+#include <sprout/algorithm/sort.hpp>
+#include <sprout/algorithm/stable_sort.hpp>
+#include <sprout/algorithm/partial_sort.hpp>
+#include <sprout/algorithm/nth_element.hpp>
+#include <sprout/algorithm/merge.hpp>
+#include <sprout/algorithm/inplace_merge.hpp>
+#include <sprout/algorithm/set_union.hpp>
+#include <sprout/algorithm/set_intersection.hpp>
+#include <sprout/algorithm/set_difference.hpp>
+#include <sprout/algorithm/set_symmetric_difference.hpp>
+#include <sprout/algorithm/push_heap.hpp>
+#include <sprout/algorithm/pop_heap.hpp>
+#include <sprout/algorithm/make_heap.hpp>
+#include <sprout/algorithm/make_partial_heap.hpp>
+#include <sprout/algorithm/sort_heap.hpp>
+#include <sprout/algorithm/next_permutation.hpp>
+#include <sprout/algorithm/prev_permutation.hpp>
+#include <sprout/algorithm/copy_while.hpp>
+#include <sprout/algorithm/copy_until.hpp>
+#include <sprout/algorithm/clamp_range.hpp>
+#include <sprout/algorithm/clamp_range_copy.hpp>
+#include <sprout/algorithm/swap_element.hpp>
+#include <sprout/algorithm/swap_element_copy.hpp>
+#include <sprout/algorithm/random_swap.hpp>
+#include <sprout/algorithm/random_swap_result.hpp>
+#include <sprout/algorithm/bogo_sort.hpp>
+#include <sprout/algorithm/bogo_sort_result.hpp>
+#include <sprout/algorithm/bozo_sort.hpp>
+#include <sprout/algorithm/bozo_sort_result.hpp>
 
 #endif	// #ifndef SPROUT_ALGORITHM_MODIFYIING_HPP
diff --git a/sprout/algorithm/move.hpp b/sprout/algorithm/move.hpp
new file mode 100644
index 00000000..ecf2570c
--- /dev/null
+++ b/sprout/algorithm/move.hpp
@@ -0,0 +1,33 @@
+/*=============================================================================
+  Copyright (c) 2011-2013 Bolero MURAKAMI
+  https://github.com/bolero-MURAKAMI/Sprout
+
+  Distributed under the Boost Software License, Version 1.0. (See accompanying
+  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+=============================================================================*/
+#ifndef SPROUT_ALGORITHM_MOVE_HPP
+#define SPROUT_ALGORITHM_MOVE_HPP
+
+#include <sprout/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+#include <sprout/iterator/type_traits/is_iterator_of.hpp>
+#include <sprout/utility/move.hpp>
+
+namespace sprout {
+	//
+	// 25.3.2 Move
+	//
+	template<
+		typename InputIterator, typename OutputIterator,
+		typename sprout::enabler_if<sprout::is_output_iterator<OutputIterator>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CXX14_CONSTEXPR OutputIterator
+	move(InputIterator first, InputIterator last, OutputIterator result) {
+		while (first != last) {
+			*result++ = sprout::move(*first++);
+		}
+		return result;
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_ALGORITHM_MOVE_HPP
diff --git a/sprout/algorithm/move_backward.hpp b/sprout/algorithm/move_backward.hpp
new file mode 100644
index 00000000..a931b846
--- /dev/null
+++ b/sprout/algorithm/move_backward.hpp
@@ -0,0 +1,33 @@
+/*=============================================================================
+  Copyright (c) 2011-2013 Bolero MURAKAMI
+  https://github.com/bolero-MURAKAMI/Sprout
+
+  Distributed under the Boost Software License, Version 1.0. (See accompanying
+  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+=============================================================================*/
+#ifndef SPROUT_ALGORITHM_MOVE_BACKWARD_HPP
+#define SPROUT_ALGORITHM_MOVE_BACKWARD_HPP
+
+#include <sprout/config.hpp>
+#include <sprout/type_traits/enabler_if.hpp>
+#include <sprout/iterator/type_traits/is_iterator_of.hpp>
+#include <sprout/utility/move.hpp>
+
+namespace sprout {
+	//
+	// 25.3.2 Move
+	//
+	template<
+		typename InputIterator, typename OutputIterator,
+		typename sprout::enabler_if<sprout::is_output_iterator<OutputIterator>::value>::type = sprout::enabler
+	>
+	inline SPROUT_CXX14_CONSTEXPR OutputIterator
+	move_backward(InputIterator first, InputIterator last, OutputIterator result) {
+		while (first != last) {
+			*--result = sprout::move(*--first);
+		}
+		return result;
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_ALGORITHM_MOVE_BACKWARD_HPP
diff --git a/sprout/algorithm/swap_ranges.hpp b/sprout/algorithm/swap_ranges.hpp
new file mode 100644
index 00000000..5cdaf6b3
--- /dev/null
+++ b/sprout/algorithm/swap_ranges.hpp
@@ -0,0 +1,28 @@
+/*=============================================================================
+  Copyright (c) 2011-2013 Bolero MURAKAMI
+  https://github.com/bolero-MURAKAMI/Sprout
+
+  Distributed under the Boost Software License, Version 1.0. (See accompanying
+  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+=============================================================================*/
+#ifndef SPROUT_ALGORITHM_SWAP_RANGES_HPP
+#define SPROUT_ALGORITHM_SWAP_RANGES_HPP
+
+#include <sprout/config.hpp>
+#include <sprout/algorithm/iter_swap.hpp>
+
+namespace sprout {
+	//
+	// 25.3.3 swap
+	//
+	template<typename ForwardIterator1, typename ForwardIterator2>
+	inline SPROUT_CXX14_CONSTEXPR ForwardIterator2
+	swap_ranges(ForwardIterator1 first1, ForwardIterator1 last1, ForwardIterator2 first2) {
+		while (first1 != last1) {
+			sprout::iter_swap(*first1++, *first2++);
+		}
+		return first2;
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_ALGORITHM_SWAP_RANGES_HPP
diff --git a/sprout/iterator/back_insert_iterator.hpp b/sprout/iterator/back_insert_iterator.hpp
index 38bb4bf5..f3e25ed8 100644
--- a/sprout/iterator/back_insert_iterator.hpp
+++ b/sprout/iterator/back_insert_iterator.hpp
@@ -63,6 +63,9 @@ namespace sprout {
 			container->push_back(sprout::move(value));
 			return *this;
 		}
+		SPROUT_CONSTEXPR back_insert_iterator& operator*() const {
+			return *this;
+		}
 		SPROUT_CXX14_CONSTEXPR back_insert_iterator& operator*() {
 			return *this;
 		}
diff --git a/sprout/iterator/front_insert_iterator.hpp b/sprout/iterator/front_insert_iterator.hpp
index 7253796d..bffc7bdd 100644
--- a/sprout/iterator/front_insert_iterator.hpp
+++ b/sprout/iterator/front_insert_iterator.hpp
@@ -63,6 +63,9 @@ namespace sprout {
 			container->push_front(sprout::move(value));
 			return *this;
 		}
+		SPROUT_CONSTEXPR front_insert_iterator& operator*() const {
+			return *this;
+		}
 		SPROUT_CXX14_CONSTEXPR front_insert_iterator& operator*() {
 			return *this;
 		}
diff --git a/sprout/iterator/insert_iterator.hpp b/sprout/iterator/insert_iterator.hpp
index 585ea1aa..f6525e9c 100644
--- a/sprout/iterator/insert_iterator.hpp
+++ b/sprout/iterator/insert_iterator.hpp
@@ -70,6 +70,9 @@ namespace sprout {
 			container->insert(iter, sprout::move(value));
 			return *this;
 		}
+		SPROUT_CONSTEXPR insert_iterator& operator*() const {
+			return *this;
+		}
 		SPROUT_CXX14_CONSTEXPR insert_iterator& operator*() {
 			return *this;
 		}
diff --git a/sprout/utility/exchange.hpp b/sprout/utility/exchange.hpp
new file mode 100644
index 00000000..314b1ead
--- /dev/null
+++ b/sprout/utility/exchange.hpp
@@ -0,0 +1,28 @@
+/*=============================================================================
+  Copyright (c) 2011-2013 Bolero MURAKAMI
+  https://github.com/bolero-MURAKAMI/Sprout
+
+  Distributed under the Boost Software License, Version 1.0. (See accompanying
+  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+=============================================================================*/
+#ifndef SPROUT_UTILITY_EXCAHNGE_HPP
+#define SPROUT_UTILITY_EXCAHNGE_HPP
+
+#include <sprout/config.hpp>
+#include <sprout/utility/forward.hpp>
+#include <sprout/utility/move.hpp>
+
+namespace sprout {
+	//
+	// 20.2.3 exchange
+	//
+	template<typename T, typename U = T>
+	inline SPROUT_CXX14_CONSTEXPR T
+	exchange(T& obj, U&& new_val) {
+		T old_val = sprout::move(obj);
+		obj = sprout::forward<U>(new_val);
+		return old_val;
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_UTILITY_EXCAHNGE_HPP
diff --git a/sprout/utility/operation.hpp b/sprout/utility/operation.hpp
index 6bc835ab..86daf706 100644
--- a/sprout/utility/operation.hpp
+++ b/sprout/utility/operation.hpp
@@ -13,5 +13,6 @@
 #include <sprout/utility/forward.hpp>
 #include <sprout/utility/move.hpp>
 #include <sprout/utility/swap.hpp>
+#include <sprout/utility/exchange.hpp>
 
 #endif	// #ifndef SPROUT_UTILITY_OPERATION_HPP
diff --git a/sprout/utility/pair/pair.hpp b/sprout/utility/pair/pair.hpp
index 5350c334..db2ff7ba 100644
--- a/sprout/utility/pair/pair.hpp
+++ b/sprout/utility/pair/pair.hpp
@@ -73,7 +73,7 @@ namespace sprout {
 		typename U, typename V,
 		typename
 	>
-	inline sprout::pair<T1, T2>& sprout::pair<T1, T2>::operator=(sprout::tuples::tuple<U, V> const& rhs) {
+	inline SPROUT_CXX14_CONSTEXPR sprout::pair<T1, T2>& sprout::pair<T1, T2>::operator=(sprout::tuples::tuple<U, V> const& rhs) {
 		first = sprout::tuples::get<0>(rhs);
 		second = sprout::tuples::get<0>(rhs);
 		return *this;
@@ -83,7 +83,7 @@ namespace sprout {
 		typename U, typename V,
 		typename
 	>
-	inline sprout::pair<T1, T2>& sprout::pair<T1, T2>::operator=(sprout::tuples::tuple<U, V>&& rhs) {
+	inline SPROUT_CXX14_CONSTEXPR sprout::pair<T1, T2>& sprout::pair<T1, T2>::operator=(sprout::tuples::tuple<U, V>&& rhs) {
 		first = sprout::forward<U>(sprout::tuples::get<0>(rhs));
 		second = sprout::forward<V>(sprout::tuples::get<1>(rhs));
 		return *this;
diff --git a/sprout/utility/pair/pair_decl.hpp b/sprout/utility/pair/pair_decl.hpp
index ff34e533..f0d72be5 100644
--- a/sprout/utility/pair/pair_decl.hpp
+++ b/sprout/utility/pair/pair_decl.hpp
@@ -103,7 +103,7 @@ namespace sprout {
 		SPROUT_CONSTEXPR pair(sprout::tuples::tuple<U, V>&& other);
 
 		pair& operator=(pair const& rhs) = default;
-		pair& operator=(pair&& rhs)
+		SPROUT_CXX14_CONSTEXPR pair& operator=(pair&& rhs)
 		SPROUT_NOEXCEPT_EXPR(std::is_nothrow_move_assignable<T1>::value && std::is_nothrow_move_assignable<T2>::value)
 		{
 			first = sprout::forward<T1>(rhs.first);
@@ -116,7 +116,7 @@ namespace sprout {
 				std::is_assignable<first_type&, U const&>::value && std::is_assignable<second_type&, V const&>::value
 			>::type
 		>
-		pair& operator=(sprout::pair<U, V> const& rhs) {
+		SPROUT_CXX14_CONSTEXPR pair& operator=(sprout::pair<U, V> const& rhs) {
 			first = rhs.first;
 			second = rhs.second;
 			return *this;
@@ -127,7 +127,7 @@ namespace sprout {
 				std::is_assignable<first_type&, U&&>::value && std::is_assignable<second_type&, V&&>::value
 			>::type
 		>
-		pair& operator=(sprout::pair<U, V>&& rhs) {
+		SPROUT_CXX14_CONSTEXPR pair& operator=(sprout::pair<U, V>&& rhs) {
 			first = sprout::forward<U>(rhs.first);
 			second = sprout::forward<V>(rhs.second);
 			return *this;
@@ -138,16 +138,16 @@ namespace sprout {
 				std::is_assignable<first_type&, U const&>::value && std::is_assignable<second_type&, V const&>::value
 			>::type
 		>
-		pair& operator=(sprout::tuples::tuple<U, V> const& rhs);
+		SPROUT_CXX14_CONSTEXPR pair& operator=(sprout::tuples::tuple<U, V> const& rhs);
 		template<
 			typename U, typename V,
 			typename = typename std::enable_if<
 				std::is_assignable<first_type&, U&&>::value && std::is_assignable<second_type&, V&&>::value
 			>::type
 		>
-		pair& operator=(sprout::tuples::tuple<U, V>&& rhs);
+		SPROUT_CXX14_CONSTEXPR pair& operator=(sprout::tuples::tuple<U, V>&& rhs);
 
-		void swap(pair& other)
+		SPROUT_CXX14_CONSTEXPR void swap(pair& other)
 		SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(sprout::swap(first, other.first)) && SPROUT_NOEXCEPT_EXPR(sprout::swap(second, other.second))) {
 			sprout::swap(first, other.first);
 			sprout::swap(second, other.second);
@@ -158,7 +158,7 @@ namespace sprout {
 	// swap
 	//
 	template<typename T1, typename T2>
-	inline void
+	inline SPROUT_CXX14_CONSTEXPR void
 	swap(sprout::pair<T1, T2>& lhs, sprout::pair<T1, T2>& rhs)
 	SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(lhs.swap(rhs)))
 	{
diff --git a/sprout/utility/string_ref/string_ref.hpp b/sprout/utility/string_ref/string_ref.hpp
index 480ef330..8dd9e8c6 100644
--- a/sprout/utility/string_ref/string_ref.hpp
+++ b/sprout/utility/string_ref/string_ref.hpp
@@ -77,6 +77,7 @@ namespace sprout {
 	private:
 		const_pointer ptr_;
 		size_type len_;
+	private:
 	public:
 		// construct/copy/destroy:
 		SPROUT_CONSTEXPR basic_string_ref()
@@ -100,7 +101,7 @@ namespace sprout {
 		{}
 		// iterators:
 #if SPROUT_USE_INDEX_ITERATOR_IMPLEMENTATION
-		iterator
+		SPROUT_CXX14_CONSTEXPR iterator
 		begin() SPROUT_NOEXCEPT {
 			return iterator(*this, 0);
 		}
@@ -108,7 +109,7 @@ namespace sprout {
 		begin() const SPROUT_NOEXCEPT {
 			return const_iterator(*this, 0);
 		}
-		iterator
+		SPROUT_CXX14_CONSTEXPR iterator
 		end() SPROUT_NOEXCEPT {
 			return iterator(*this, size());
 		}
@@ -117,10 +118,18 @@ namespace sprout {
 			return const_iterator(*this, size());
 		}
 #else
+		SPROUT_CXX14_CONSTEXPR iterator
+		begin() SPROUT_NOEXCEPT {
+			return data();
+		}
 		SPROUT_CONSTEXPR const_iterator
 		begin() const SPROUT_NOEXCEPT {
 			return data();
 		}
+		SPROUT_CXX14_CONSTEXPR iterator
+		end() SPROUT_NOEXCEPT {
+			return data() + size();
+		}
 		SPROUT_CONSTEXPR const_iterator
 		end() const SPROUT_NOEXCEPT {
 			return data() + size();
@@ -174,7 +183,7 @@ namespace sprout {
 		max_size() const SPROUT_NOEXCEPT {
 			return size();
 		}
-		void
+		SPROUT_CXX14_CONSTEXPR void
 		clear() {
 			len_ = 0;
 		}
@@ -202,14 +211,14 @@ namespace sprout {
 			return ptr_[size() - 1];
 		}
 		// modifiers:
-		void
+		SPROUT_CXX14_CONSTEXPR void
 		swap(basic_string_ref& other)
 		SPROUT_NOEXCEPT
 		{
 			sprout::swap(ptr_, other.ptr_);
 			sprout::swap(len_, other.len_);
 		}
-		void
+		SPROUT_CXX14_CONSTEXPR void
 		remove_prefix(size_type n) {
 			if (n > size()) {
 				n = size();
@@ -223,7 +232,7 @@ namespace sprout {
 				: basic_string_ref(data() + n, size() - n)
 				;
 		}
-		void
+		SPROUT_CXX14_CONSTEXPR void
 		remove_suffix(size_type n) {
 			if (n > size()) {
 				n = size();
@@ -401,20 +410,21 @@ namespace sprout {
 		SPROUT_EXPLICIT_CONVERSION operator std::basic_string<T, Traits, Allocator>() const {
 			return std::basic_string<T, Traits, Allocator>(data(), size());
 		}
-		pointer
+		SPROUT_CONSTEXPR const_pointer
+		c_array() const SPROUT_NOEXCEPT {
+			return data();
+		}
+		SPROUT_CXX14_CONSTEXPR pointer
 		c_array() SPROUT_NOEXCEPT {
 			return data();
 		}
-		void
+		// others:
+		SPROUT_CXX14_CONSTEXPR void
 		rangecheck(size_type i) const {
 			if (i >= size()) {
 				throw std::out_of_range("basic_string_ref<>: index out of range");
 			}
 		}
-		void
-		maxcheck(size_type n) const {
-			rangecheck(n);
-		}
 
 #if SPROUT_USE_INDEX_ITERATOR_IMPLEMENTATION
 		template<typename ConstIterator>
@@ -549,7 +559,7 @@ namespace sprout {
 	// swap
 	//
 	template<typename T, typename Traits>
-	inline void
+	inline SPROUT_CXX14_CONSTEXPR void
 	swap(sprout::basic_string_ref<T, Traits>& lhs, sprout::basic_string_ref<T, Traits>& rhs)
 	SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(lhs.swap(rhs)))
 	{
diff --git a/sprout/utility/swap.hpp b/sprout/utility/swap.hpp
index a51dcca5..718f84e1 100644
--- a/sprout/utility/swap.hpp
+++ b/sprout/utility/swap.hpp
@@ -8,6 +8,7 @@
 #ifndef SPROUT_UTILITY_SWAP_HPP
 #define SPROUT_UTILITY_SWAP_HPP
 
+#include <cstddef>
 #include <utility>
 #include <sprout/config.hpp>
 
@@ -15,20 +16,29 @@ namespace sprout_swap_detail {
 	using std::swap;
 
 	template<typename T>
-	inline void
+	inline SPROUT_CXX14_CONSTEXPR void
 	swap_impl(T& a, T& b)
 	SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(swap(a, b)))
 	{
-		return swap(a, b);
+		swap(a, b);
+	}
+	template<typename T, std::size_t N>
+	inline SPROUT_CXX14_CONSTEXPR void
+	swap_impl(T (& a)[N], T (& b)[N])
+	SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(swap(*a, *b)))
+	{
+		for (std::size_t i = 0; i < N; ++i) {
+			swap(a[i], b[i]);
+		}
 	}
 }	// namespace sprout_swap_detail
 
 namespace sprout {
 	//
-	// swap
+	// 20.2.2 swap
 	//
 	template<typename T1, typename T2>
-	inline void
+	inline SPROUT_CXX14_CONSTEXPR void
 	swap(T1& lhs, T2& rhs)
 	SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(sprout_swap_detail::swap_impl(lhs, rhs)))
 	{
diff --git a/sprout/utility/value_holder/value_holder.hpp b/sprout/utility/value_holder/value_holder.hpp
index 8dc60aa7..d671dac0 100644
--- a/sprout/utility/value_holder/value_holder.hpp
+++ b/sprout/utility/value_holder/value_holder.hpp
@@ -236,61 +236,61 @@ namespace sprout {
 
 		value_holder& operator=(value_holder const&) = default;
 		value_holder& operator=(value_holder&&) = default;
-		value_holder& operator=(argument_type p) {
+		SPROUT_CXX14_CONSTEXPR value_holder& operator=(argument_type p) {
 			value_holder temp(p);
 			temp.swap(*this);
 			return *this;
 		}
-		value_holder& operator=(movable_argument_type p) {
+		SPROUT_CXX14_CONSTEXPR value_holder& operator=(movable_argument_type p) {
 			value_holder temp(sprout::move(p));
 			temp.swap(*this);
 			return *this;
 		}
 
-		void swap(value_holder& other)
+		SPROUT_CXX14_CONSTEXPR void swap(value_holder& other)
 		SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(sprout::swap(holder_, other.holder_)))
 		{
 			sprout::swap(holder_, other.holder_);
 		}
 
-		operator reference() {
+		SPROUT_CXX14_CONSTEXPR operator reference() {
 			return helper_type::ref(holder_);
 		}
 		SPROUT_CONSTEXPR operator mutable_or_const_reference() const {
 			return helper_type::ref(holder_);
 		}
-		reference operator*() {
+		SPROUT_CXX14_CONSTEXPR reference operator*() {
 			return helper_type::ref(holder_);
 		}
 		SPROUT_CONSTEXPR mutable_or_const_reference operator*() const {
 			return helper_type::ref(holder_);
 		}
-		reference get() {
+		SPROUT_CXX14_CONSTEXPR reference get() {
 			return helper_type::ref(holder_);
 		}
 		SPROUT_CONSTEXPR mutable_or_const_reference get() const {
 			return helper_type::ref(holder_);
 		}
-		reference value() {
+		SPROUT_CXX14_CONSTEXPR reference value() {
 			return get();
 		}
 		SPROUT_CONSTEXPR mutable_or_const_reference value() const {
 			return get();
 		}
 
-		pointer operator->() SPROUT_NOEXCEPT {
+		SPROUT_CXX14_CONSTEXPR pointer operator->() SPROUT_NOEXCEPT {
 			return helper_type::ptr(holder_);
 		}
 		SPROUT_CONSTEXPR mutable_or_const_pointer operator->() const SPROUT_NOEXCEPT {
 			return helper_type::ptr(holder_);
 		}
-		pointer get_pointer() SPROUT_NOEXCEPT {
+		SPROUT_CXX14_CONSTEXPR pointer get_pointer() SPROUT_NOEXCEPT {
 			return helper_type::ptr(holder_);
 		}
 		SPROUT_CONSTEXPR mutable_or_const_pointer get_pointer() const SPROUT_NOEXCEPT {
 			return helper_type::ptr(holder_);
 		}
-		pointer get_ptr() SPROUT_NOEXCEPT {
+		SPROUT_CXX14_CONSTEXPR pointer get_ptr() SPROUT_NOEXCEPT {
 			return get_pointer();
 		}
 		SPROUT_CONSTEXPR mutable_or_const_pointer get_ptr() const SPROUT_NOEXCEPT {
@@ -305,7 +305,7 @@ namespace sprout {
 	// swap
 	//
 	template<typename T>
-	inline void
+	inline SPROUT_CXX14_CONSTEXPR void
 	swap(sprout::value_holder<T>& lhs, sprout::value_holder<T>& rhs)
 	SPROUT_NOEXCEPT_EXPR(SPROUT_NOEXCEPT_EXPR(lhs.swap(rhs)))
 	{