From a90bbd5f380c632ed76138ec790bed45dc2ffb2e Mon Sep 17 00:00:00 2001
From: bolero-MURAKAMI <bolero.murakami@gmail.com>
Date: Sat, 5 Oct 2013 13:35:26 +0900
Subject: [PATCH] add advance C++14 constexpr version

---
 sprout/algorithm/detail/max.hpp               | 31 ++++++++++
 sprout/algorithm/detail/min.hpp               | 31 ++++++++++
 sprout/algorithm/fixed/copy.hpp               |  2 +-
 sprout/algorithm/fixed/copy_backward.hpp      |  2 +-
 sprout/algorithm/fixed/copy_n.hpp             |  2 +-
 sprout/algorithm/max.hpp                      | 13 +----
 sprout/algorithm/max_element.hpp              |  3 +-
 sprout/algorithm/min.hpp                      | 13 +----
 sprout/algorithm/min_element.hpp              |  3 +-
 sprout/compost/utility/rosenberg.hpp          |  1 -
 sprout/config/compiler/clang.hpp              |  4 +-
 sprout/config/compiler/gcc.hpp                |  4 +-
 sprout/iterator/advance.hpp                   | 56 +++++++++++++++++++
 sprout/iterator/next.hpp                      |  3 +-
 sprout/iterator/operation.hpp                 |  1 +
 sprout/math/equal_to.hpp                      |  2 +-
 .../numeric/dft/fixed/amplitude_spectrum.hpp  |  2 +-
 sprout/numeric/dft/fixed/dft.hpp              |  2 +-
 sprout/numeric/dft/fixed/idft.hpp             |  2 +-
 sprout/numeric/dft/fixed/phase_spectrum.hpp   |  2 +-
 sprout/numeric/dft/fixed/sawtooth.hpp         |  1 -
 sprout/numeric/dft/fixed/sinusoid.hpp         |  1 -
 sprout/numeric/dft/fixed/square.hpp           |  1 -
 sprout/numeric/dft/fixed/triangle.hpp         |  1 -
 sprout/random/inversive_congruential.hpp      |  2 +-
 sprout/random/linear_congruential.hpp         |  2 +-
 sprout/string/string.hpp                      |  2 +-
 sprout/variant/variant.hpp                    |  2 +-
 28 files changed, 145 insertions(+), 46 deletions(-)
 create mode 100644 sprout/algorithm/detail/max.hpp
 create mode 100644 sprout/algorithm/detail/min.hpp
 create mode 100644 sprout/iterator/advance.hpp

diff --git a/sprout/algorithm/detail/max.hpp b/sprout/algorithm/detail/max.hpp
new file mode 100644
index 00000000..256682ce
--- /dev/null
+++ b/sprout/algorithm/detail/max.hpp
@@ -0,0 +1,31 @@
+/*=============================================================================
+  Copyright (c) 2011-2013 Bolero MURAKAMI
+  Copyright (C) 2011 RiSK (sscrisk)
+  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_DETAIL_MAX_HPP
+#define SPROUT_ALGORITHM_DETAIL_MAX_HPP
+
+#include <sprout/config.hpp>
+#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
+
+namespace sprout {
+
+	// 25.4.7 Minimum and maximum
+	template<typename T, typename Compare>
+	inline SPROUT_CONSTEXPR T const&
+	max(T const& a, T const& b, Compare comp) {
+		return comp(a, b) ? b : a;
+	}
+
+	template<typename T>
+	inline SPROUT_CONSTEXPR T const&
+	max(T const& a, T const& b) {
+		return sprout::max(a, b, NS_SSCRISK_CEL_OR_SPROUT::less<T>());
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_ALGORITHM_DETAIL_MAX_HPP
diff --git a/sprout/algorithm/detail/min.hpp b/sprout/algorithm/detail/min.hpp
new file mode 100644
index 00000000..972e5a63
--- /dev/null
+++ b/sprout/algorithm/detail/min.hpp
@@ -0,0 +1,31 @@
+/*=============================================================================
+  Copyright (c) 2011-2013 Bolero MURAKAMI
+  Copyright (C) 2011 RiSK (sscrisk)
+  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_DETAIL_MIN_HPP
+#define SPROUT_ALGORITHM_DETAIL_MIN_HPP
+
+#include <sprout/config.hpp>
+#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
+
+namespace sprout {
+
+	// 25.4.7 Minimum and maximum
+	template<typename T, typename Compare>
+	inline SPROUT_CONSTEXPR T const&
+	min(T const& a, T const& b, Compare comp) {
+		return comp(b, a) ? b : a;
+	}
+
+	template<typename T>
+	inline SPROUT_CONSTEXPR T const&
+	min(T const& a, T const& b) {
+		return sprout::min(a, b, NS_SSCRISK_CEL_OR_SPROUT::less<T>());
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_ALGORITHM_DETAIL_MIN_HPP
diff --git a/sprout/algorithm/fixed/copy.hpp b/sprout/algorithm/fixed/copy.hpp
index dee70dde..6f257c30 100644
--- a/sprout/algorithm/fixed/copy.hpp
+++ b/sprout/algorithm/fixed/copy.hpp
@@ -18,7 +18,7 @@
 #include <sprout/iterator/operation.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/less.hpp>
 #include <sprout/detail/container_complate.hpp>
 
 namespace sprout {
diff --git a/sprout/algorithm/fixed/copy_backward.hpp b/sprout/algorithm/fixed/copy_backward.hpp
index 64899697..a122f3bf 100644
--- a/sprout/algorithm/fixed/copy_backward.hpp
+++ b/sprout/algorithm/fixed/copy_backward.hpp
@@ -18,7 +18,7 @@
 #include <sprout/iterator/operation.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/greater_equal.hpp>
 #include <sprout/detail/container_complate_backward.hpp>
 
 namespace sprout {
diff --git a/sprout/algorithm/fixed/copy_n.hpp b/sprout/algorithm/fixed/copy_n.hpp
index d1c70d2b..fcf32022 100644
--- a/sprout/algorithm/fixed/copy_n.hpp
+++ b/sprout/algorithm/fixed/copy_n.hpp
@@ -17,7 +17,7 @@
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/algorithm/fixed/copy.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/less.hpp>
 #include <sprout/detail/container_complate.hpp>
 #include <sprout/iterator/type_traits/category.hpp>
 
diff --git a/sprout/algorithm/max.hpp b/sprout/algorithm/max.hpp
index db3b6e7e..54a8cb6b 100644
--- a/sprout/algorithm/max.hpp
+++ b/sprout/algorithm/max.hpp
@@ -11,6 +11,7 @@
 
 #include <initializer_list>
 #include <sprout/config.hpp>
+#include <sprout/algorithm/detail/max.hpp>
 #include <sprout/algorithm/max_element.hpp>
 #include <sprout/iterator/ptr_index_iterator.hpp>
 #include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
@@ -18,18 +19,6 @@
 namespace sprout {
 
 	// 25.4.7 Minimum and maximum
-	template<typename T, typename Compare>
-	inline SPROUT_CONSTEXPR T const&
-	max(T const& a, T const& b, Compare comp) {
-		return comp(a, b) ? b : a;
-	}
-
-	template<typename T>
-	inline SPROUT_CONSTEXPR T const&
-	max(T const& a, T const& b) {
-		return sprout::max(a, b, NS_SSCRISK_CEL_OR_SPROUT::less<T>());
-	}
-
 #ifdef SPROUT_NO_CXX14_INITIALIZER_LIST
 	template<typename T, typename Compare>
 	inline SPROUT_CONSTEXPR T
diff --git a/sprout/algorithm/max_element.hpp b/sprout/algorithm/max_element.hpp
index e6f2534e..825b6b64 100644
--- a/sprout/algorithm/max_element.hpp
+++ b/sprout/algorithm/max_element.hpp
@@ -11,7 +11,8 @@
 #include <iterator>
 #include <type_traits>
 #include <sprout/config.hpp>
-#include <sprout/iterator/operation.hpp>
+#include <sprout/iterator/next.hpp>
+#include <sprout/iterator/distance.hpp>
 #include <sprout/iterator/type_traits/category.hpp>
 #include <sprout/utility/pair/pair.hpp>
 #include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
diff --git a/sprout/algorithm/min.hpp b/sprout/algorithm/min.hpp
index 586cd8ec..bbf4636f 100644
--- a/sprout/algorithm/min.hpp
+++ b/sprout/algorithm/min.hpp
@@ -11,6 +11,7 @@
 
 #include <initializer_list>
 #include <sprout/config.hpp>
+#include <sprout/algorithm/detail/min.hpp>
 #include <sprout/algorithm/min_element.hpp>
 #include <sprout/iterator/ptr_index_iterator.hpp>
 #include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
@@ -18,18 +19,6 @@
 namespace sprout {
 
 	// 25.4.7 Minimum and maximum
-	template<typename T, typename Compare>
-	inline SPROUT_CONSTEXPR T const&
-	min(T const& a, T const& b, Compare comp) {
-		return comp(b, a) ? b : a;
-	}
-
-	template<typename T>
-	inline SPROUT_CONSTEXPR T const&
-	min(T const& a, T const& b) {
-		return sprout::min(a, b, NS_SSCRISK_CEL_OR_SPROUT::less<T>());
-	}
-
 #ifdef SPROUT_NO_CXX14_INITIALIZER_LIST
 	template<typename T, typename Compare>
 	inline SPROUT_CONSTEXPR T
diff --git a/sprout/algorithm/min_element.hpp b/sprout/algorithm/min_element.hpp
index 7be0461d..533a9d5b 100644
--- a/sprout/algorithm/min_element.hpp
+++ b/sprout/algorithm/min_element.hpp
@@ -11,7 +11,8 @@
 #include <iterator>
 #include <type_traits>
 #include <sprout/config.hpp>
-#include <sprout/iterator/operation.hpp>
+#include <sprout/iterator/next.hpp>
+#include <sprout/iterator/distance.hpp>
 #include <sprout/iterator/type_traits/category.hpp>
 #include <sprout/utility/pair/pair.hpp>
 #include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
diff --git a/sprout/compost/utility/rosenberg.hpp b/sprout/compost/utility/rosenberg.hpp
index aabd4486..81a469d5 100644
--- a/sprout/compost/utility/rosenberg.hpp
+++ b/sprout/compost/utility/rosenberg.hpp
@@ -11,7 +11,6 @@
 #include <sprout/config.hpp>
 #include <sprout/detail/pow.hpp>
 #include <sprout/type_traits/float_promote.hpp>
-#include <sprout/math/comparison.hpp>
 
 namespace sprout {
 	namespace compost {
diff --git a/sprout/config/compiler/clang.hpp b/sprout/config/compiler/clang.hpp
index 597415ed..5b19d686 100644
--- a/sprout/config/compiler/clang.hpp
+++ b/sprout/config/compiler/clang.hpp
@@ -44,7 +44,9 @@
 #	define SPROUT_NO_CXX11_UNICODE_LITERALS
 #endif
 
-#define SPROUT_NO_CXX14_CONSTEXPR
+#if (!__has_feature(cxx_constexpr) || __cplusplus < 201305L)
+#	define SPROUT_NO_CXX14_CONSTEXPR
+#endif
 
 #if !defined(SPROUT_NO_CXX11_CONSTEXPR)
 #	define SPROUT_WORKAROUND_NOT_TERMINATE_RECURSIVE_CONSTEXPR_FUNCTION_TEMPLATE
diff --git a/sprout/config/compiler/gcc.hpp b/sprout/config/compiler/gcc.hpp
index 3c744e55..e6294faf 100644
--- a/sprout/config/compiler/gcc.hpp
+++ b/sprout/config/compiler/gcc.hpp
@@ -52,6 +52,8 @@
 #	define SPROUT_HAS_CONSTEXPR_BIT_OPERATION
 #endif
 
-#define SPROUT_NO_CXX14_CONSTEXPR
+#if (__GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 9) || __cplusplus < 201300L)
+#	define SPROUT_NO_CXX14_CONSTEXPR
+#endif
 
 #endif	// #ifndef SPROUT_CONFIG_COMPILER_GCC_HPP
diff --git a/sprout/iterator/advance.hpp b/sprout/iterator/advance.hpp
new file mode 100644
index 00000000..a12c5bd6
--- /dev/null
+++ b/sprout/iterator/advance.hpp
@@ -0,0 +1,56 @@
+/*=============================================================================
+  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_ITERATOR_ADVANCE_HPP
+#define SPROUT_ITERATOR_ADVANCE_HPP
+
+#include <iterator>
+#include <sprout/config.hpp>
+#include <sprout/assert.hpp>
+#include <sprout/math/greater_equal.hpp>
+
+namespace sprout {
+	namespace detail {
+		template<typename InputIterator, typename Distance>
+		inline SPROUT_CXX14_CONSTEXPR void
+		advance_impl(InputIterator& it, Distance n, std::input_iterator_tag*) {
+			SPROUT_ASSERT(sprout::math::greater_equal(n, 0));
+			for (; 0 < n; --n) {
+				++it;
+			}
+		}
+		template<typename BidirectionalIterator, typename Distance>
+		inline SPROUT_CXX14_CONSTEXPR void
+		advance_impl(BidirectionalIterator& it, Distance n, std::bidirectional_iterator_tag*) {
+			if (n > 0) {
+				for (; 0 < n; --n) {
+					++it;
+				}
+			} else {
+				for (; n < 0; ++n) {
+					--it;
+				}
+			}
+		}
+		template<typename RandomAccessIterator, typename Distance>
+		inline SPROUT_CXX14_CONSTEXPR void
+		advance_impl(RandomAccessIterator& it, Distance n, std::random_access_iterator_tag*) {
+			it += n;
+		}
+	}	// namespace detail
+	//
+	// advance
+	//
+	template<typename Iterator, typename Distance>
+	inline SPROUT_CXX14_CONSTEXPR void
+	advance(Iterator& it, Distance n) {
+		typedef typename std::iterator_traits<Iterator>::iterator_category* category;
+		sprout::detail::advance_impl(it, n, category());
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_ITERATOR_ADVANCE_HPP
diff --git a/sprout/iterator/next.hpp b/sprout/iterator/next.hpp
index c750a779..b728791d 100644
--- a/sprout/iterator/next.hpp
+++ b/sprout/iterator/next.hpp
@@ -15,6 +15,7 @@
 #include <sprout/iterator/prev_fwd.hpp>
 #include <sprout/adl/not_found.hpp>
 #include <sprout/assert.hpp>
+#include <sprout/math/greater_equal.hpp>
 
 namespace sprout_adl {
 	sprout::not_found_via_adl iterator_next(...);
@@ -101,7 +102,7 @@ namespace sprout {
 			std::input_iterator_tag*
 			)
 		{
-			return SPROUT_ASSERT(n >= 0),
+			return SPROUT_ASSERT(sprout::math::greater_equal(n, 0)),
 				n == 0 ? it
 					: sprout::iterator_detail::next_impl_2(it, n)
 				;
diff --git a/sprout/iterator/operation.hpp b/sprout/iterator/operation.hpp
index 6a8fdd22..bb852c42 100644
--- a/sprout/iterator/operation.hpp
+++ b/sprout/iterator/operation.hpp
@@ -12,5 +12,6 @@
 #include <sprout/iterator/next.hpp>
 #include <sprout/iterator/prev.hpp>
 #include <sprout/iterator/distance.hpp>
+#include <sprout/iterator/advance.hpp>
 
 #endif	// #ifndef SPROUT_ITERATOR_OPERATION_HPP
diff --git a/sprout/math/equal_to.hpp b/sprout/math/equal_to.hpp
index 6afeaa8d..0bf6fe13 100644
--- a/sprout/math/equal_to.hpp
+++ b/sprout/math/equal_to.hpp
@@ -11,7 +11,7 @@
 #include <type_traits>
 #include <sprout/config.hpp>
 #include <sprout/limits.hpp>
-#include <sprout/algorithm/max.hpp>
+#include <sprout/algorithm/detail/max.hpp>
 #include <sprout/math/fabs.hpp>
 #include <sprout/type_traits/arithmetic_promote.hpp>
 #include <sprout/type_traits/enabler_if.hpp>
diff --git a/sprout/numeric/dft/fixed/amplitude_spectrum.hpp b/sprout/numeric/dft/fixed/amplitude_spectrum.hpp
index 31307d81..3d0d6a1c 100644
--- a/sprout/numeric/dft/fixed/amplitude_spectrum.hpp
+++ b/sprout/numeric/dft/fixed/amplitude_spectrum.hpp
@@ -19,7 +19,7 @@
 #include <sprout/iterator/amplitude_spectrum_iterator.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/less.hpp>
 #include <sprout/numeric/dft/amplitude_spectrum_value.hpp>
 #include <sprout/detail/container_complate.hpp>
 
diff --git a/sprout/numeric/dft/fixed/dft.hpp b/sprout/numeric/dft/fixed/dft.hpp
index 091c6c90..47668ab0 100644
--- a/sprout/numeric/dft/fixed/dft.hpp
+++ b/sprout/numeric/dft/fixed/dft.hpp
@@ -19,7 +19,7 @@
 #include <sprout/iterator/dft_iterator.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/less.hpp>
 #include <sprout/numeric/dft/dft_element.hpp>
 #include <sprout/detail/container_complate.hpp>
 
diff --git a/sprout/numeric/dft/fixed/idft.hpp b/sprout/numeric/dft/fixed/idft.hpp
index 8db98096..82e2a190 100644
--- a/sprout/numeric/dft/fixed/idft.hpp
+++ b/sprout/numeric/dft/fixed/idft.hpp
@@ -19,7 +19,7 @@
 #include <sprout/iterator/idft_iterator.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/less.hpp>
 #include <sprout/numeric/dft/idft_element.hpp>
 #include <sprout/detail/container_complate.hpp>
 
diff --git a/sprout/numeric/dft/fixed/phase_spectrum.hpp b/sprout/numeric/dft/fixed/phase_spectrum.hpp
index dd6cdce6..6fdd2280 100644
--- a/sprout/numeric/dft/fixed/phase_spectrum.hpp
+++ b/sprout/numeric/dft/fixed/phase_spectrum.hpp
@@ -19,7 +19,7 @@
 #include <sprout/iterator/phase_spectrum_iterator.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/less.hpp>
 #include <sprout/numeric/dft/phase_spectrum_value.hpp>
 #include <sprout/detail/container_complate.hpp>
 
diff --git a/sprout/numeric/dft/fixed/sawtooth.hpp b/sprout/numeric/dft/fixed/sawtooth.hpp
index ca0705fc..e537c942 100644
--- a/sprout/numeric/dft/fixed/sawtooth.hpp
+++ b/sprout/numeric/dft/fixed/sawtooth.hpp
@@ -15,7 +15,6 @@
 #include <sprout/container/indexes.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
 #include <sprout/math/floor.hpp>
 #include <sprout/detail/container_complate.hpp>
 
diff --git a/sprout/numeric/dft/fixed/sinusoid.hpp b/sprout/numeric/dft/fixed/sinusoid.hpp
index b8413e74..09063cf1 100644
--- a/sprout/numeric/dft/fixed/sinusoid.hpp
+++ b/sprout/numeric/dft/fixed/sinusoid.hpp
@@ -15,7 +15,6 @@
 #include <sprout/container/indexes.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
 #include <sprout/math/constants.hpp>
 #include <sprout/math/sin.hpp>
 #include <sprout/detail/container_complate.hpp>
diff --git a/sprout/numeric/dft/fixed/square.hpp b/sprout/numeric/dft/fixed/square.hpp
index dc74bb82..0bf3a8e5 100644
--- a/sprout/numeric/dft/fixed/square.hpp
+++ b/sprout/numeric/dft/fixed/square.hpp
@@ -15,7 +15,6 @@
 #include <sprout/container/indexes.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
 #include <sprout/numeric/dft/fixed/sawtooth.hpp>
 #include <sprout/detail/container_complate.hpp>
 
diff --git a/sprout/numeric/dft/fixed/triangle.hpp b/sprout/numeric/dft/fixed/triangle.hpp
index 9bbe0036..45c1f51c 100644
--- a/sprout/numeric/dft/fixed/triangle.hpp
+++ b/sprout/numeric/dft/fixed/triangle.hpp
@@ -15,7 +15,6 @@
 #include <sprout/container/indexes.hpp>
 #include <sprout/algorithm/fixed/result_of.hpp>
 #include <sprout/pit/pit.hpp>
-#include <sprout/math/comparison.hpp>
 #include <sprout/math/sin.hpp>
 #include <sprout/math/asin.hpp>
 #include <sprout/math/constants.hpp>
diff --git a/sprout/random/inversive_congruential.hpp b/sprout/random/inversive_congruential.hpp
index 2f3c64f1..9a2987b0 100644
--- a/sprout/random/inversive_congruential.hpp
+++ b/sprout/random/inversive_congruential.hpp
@@ -15,7 +15,7 @@
 #include <sprout/limits.hpp>
 #include <sprout/random/detail/const_mod.hpp>
 #include <sprout/random/random_result.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/greater_equal.hpp>
 #include <sprout/assert.hpp>
 
 namespace sprout {
diff --git a/sprout/random/linear_congruential.hpp b/sprout/random/linear_congruential.hpp
index 8ce5a269..3e59e476 100644
--- a/sprout/random/linear_congruential.hpp
+++ b/sprout/random/linear_congruential.hpp
@@ -15,7 +15,7 @@
 #include <sprout/limits.hpp>
 #include <sprout/random/detail/const_mod.hpp>
 #include <sprout/random/random_result.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/greater_equal.hpp>
 #include <sprout/assert.hpp>
 
 namespace sprout {
diff --git a/sprout/string/string.hpp b/sprout/string/string.hpp
index 75f07ab0..55f8382a 100644
--- a/sprout/string/string.hpp
+++ b/sprout/string/string.hpp
@@ -29,7 +29,7 @@
 #include <sprout/utility/swap.hpp>
 #include <sprout/type_traits/identity.hpp>
 #include <sprout/type_traits/enabler_if.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/less.hpp>
 #include <sprout/string/char_traits.hpp>
 #include <sprout/string/npos.hpp>
 #include <sprout/string/detail/operations.hpp>
diff --git a/sprout/variant/variant.hpp b/sprout/variant/variant.hpp
index 61646f15..729c7c21 100644
--- a/sprout/variant/variant.hpp
+++ b/sprout/variant/variant.hpp
@@ -27,7 +27,7 @@
 #include <sprout/functional/type_traits/weak_result_type.hpp>
 #include <sprout/variant/variant_fwd.hpp>
 #include <sprout/variant/visitor_result.hpp>
-#include <sprout/math/comparison.hpp>
+#include <sprout/math/less.hpp>
 
 namespace sprout {
 	namespace detail {