diff --git a/sprout/stateful/counter.hpp b/sprout/stateful/counter.hpp
index 7734fea5..8af669b4 100644
--- a/sprout/stateful/counter.hpp
+++ b/sprout/stateful/counter.hpp
@@ -44,24 +44,24 @@ namespace sprout {
 		};
 
 		template<int N, int = adl_counter(sprout::counter_detail::tag<N>())>
-		SPROUT_CONSTEXPR bool check(int, sprout::counter_detail::tag<N>) {
+		inline SPROUT_CONSTEXPR bool check(int, sprout::counter_detail::tag<N>) {
 			return true;
 		}
 		template<int N>
-		SPROUT_CONSTEXPR bool check(long, sprout::counter_detail::tag<N>) {
+		inline SPROUT_CONSTEXPR bool check(long, sprout::counter_detail::tag<N>) {
 			return false;
 		}
 		template<int N>
-		SPROUT_CONSTEXPR bool check(bool R = sprout::counter_detail::check(0, sprout::counter_detail::tag<N>())) {
+		inline SPROUT_CONSTEXPR bool check(bool R = sprout::counter_detail::check(0, sprout::counter_detail::tag<N>())) {
 			return R;
 		}
 
 		template<int N>
-		SPROUT_CONSTEXPR int counter(sprout::false_type, sprout::counter_detail::tag<N>) {
+		inline SPROUT_CONSTEXPR int counter(sprout::false_type, sprout::counter_detail::tag<N>) {
 			return 0;
 		}
 		template<int N>
-		SPROUT_CONSTEXPR int counter(
+		inline SPROUT_CONSTEXPR int counter(
 			sprout::true_type, sprout::counter_detail::tag<N>,
 			int R = !sprout::counter_detail::check<N>() ? N
 				: counter(sprout::bool_constant<sprout::counter_detail::check<N>()>(), sprout::counter_detail::tag<N + 1>())
@@ -70,7 +70,7 @@ namespace sprout {
 			return R;
 		}
 		template<int N = 0>
-		SPROUT_CONSTEXPR int counter(int R = sprout::counter_detail::counter(sprout::true_type(), sprout::counter_detail::tag<N>())) {
+		inline SPROUT_CONSTEXPR int counter(int R = sprout::counter_detail::counter(sprout::true_type(), sprout::counter_detail::tag<N>())) {
 			return R;
 		}
 	}	// namespace counter_detail
@@ -83,7 +83,7 @@ namespace sprout {
 			sprout::counter_detail::counter() + N - 1
 			>::value
 	>
-	SPROUT_CONSTEXPR int counter() {
+	inline SPROUT_CONSTEXPR int counter() {
 		return R;
 	}
 
diff --git a/sprout/stateful/rand.hpp b/sprout/stateful/rand.hpp
index cafe5283..467979dc 100644
--- a/sprout/stateful/rand.hpp
+++ b/sprout/stateful/rand.hpp
@@ -144,24 +144,24 @@ namespace sprout {
 		SPROUT_CONSTEXPR_OR_CONST int sprout::rand_detail::state<0, IsSrand, Seed>::value;
 
 		template<int N, int = adl_counter(sprout::rand_detail::tag<N>())>
-		SPROUT_CONSTEXPR bool check(int, sprout::rand_detail::tag<N>) {
+		inline SPROUT_CONSTEXPR bool check(int, sprout::rand_detail::tag<N>) {
 			return true;
 		}
 		template<int N>
-		SPROUT_CONSTEXPR bool check(long, sprout::rand_detail::tag<N>) {
+		inline SPROUT_CONSTEXPR bool check(long, sprout::rand_detail::tag<N>) {
 			return false;
 		}
 		template<int N>
-		SPROUT_CONSTEXPR bool check(bool R = sprout::rand_detail::check(0, sprout::rand_detail::tag<N>())) {
+		inline SPROUT_CONSTEXPR bool check(bool R = sprout::rand_detail::check(0, sprout::rand_detail::tag<N>())) {
 			return R;
 		}
 
 		template<int N>
-		SPROUT_CONSTEXPR int counter(sprout::false_type, sprout::rand_detail::tag<N>) {
+		inline SPROUT_CONSTEXPR int counter(sprout::false_type, sprout::rand_detail::tag<N>) {
 			return 0;
 		}
 		template<int N>
-		SPROUT_CONSTEXPR int counter(
+		inline SPROUT_CONSTEXPR int counter(
 			sprout::true_type, sprout::rand_detail::tag<N>,
 			int R = !sprout::rand_detail::check<N>() ? N
 				: counter(sprout::bool_constant<sprout::rand_detail::check<N>()>(), sprout::rand_detail::tag<N + 1>())
@@ -170,7 +170,7 @@ namespace sprout {
 			return R;
 		}
 		template<int N = 0>
-		SPROUT_CONSTEXPR int counter(int R = sprout::rand_detail::counter(sprout::true_type(), sprout::rand_detail::tag<N>())) {
+		inline SPROUT_CONSTEXPR int counter(int R = sprout::rand_detail::counter(sprout::true_type(), sprout::rand_detail::tag<N>())) {
 			return R;
 		}
 	}	// namespace rand_detail
@@ -183,7 +183,7 @@ namespace sprout {
 			sprout::rand_detail::counter() + N - 1
 			>::value
 	>
-	SPROUT_CONSTEXPR int rand() {
+	inline SPROUT_CONSTEXPR int rand() {
 		return R;
 	}
 
@@ -208,7 +208,7 @@ namespace sprout {
 			true, Seed
 			>::value
 	>
-	SPROUT_CONSTEXPR unsigned srand_return() {
+	inline SPROUT_CONSTEXPR unsigned srand_return() {
 		return R;
 	}
 
diff --git a/sprout/stateful/typed_counter.hpp b/sprout/stateful/typed_counter.hpp
index e1c8680f..9d9c3b81 100644
--- a/sprout/stateful/typed_counter.hpp
+++ b/sprout/stateful/typed_counter.hpp
@@ -87,7 +87,7 @@ namespace sprout {
 			sprout::typed_counter_detail::typed<T>::template counter(sprout::true_type(), typename sprout::typed_counter_detail::typed<T>::template tag<N - 1>()) + N - 1
 			>::value
 	>
-	SPROUT_CONSTEXPR int counter() {
+	inline SPROUT_CONSTEXPR int counter() {
 		return R;
 	}
 
diff --git a/sprout/stateful/typed_rand.hpp b/sprout/stateful/typed_rand.hpp
index 084ea77d..14c86ceb 100644
--- a/sprout/stateful/typed_rand.hpp
+++ b/sprout/stateful/typed_rand.hpp
@@ -178,7 +178,7 @@ namespace sprout {
 			sprout::typed_rand_detail::typed<T>::template counter(sprout::true_type(), typename sprout::typed_rand_detail::typed<T>::template tag<N - 1>()) + N - 1
 			>::value
 	>
-	SPROUT_CONSTEXPR int rand() {
+	inline SPROUT_CONSTEXPR int rand() {
 		return R;
 	}
 
@@ -194,7 +194,7 @@ namespace sprout {
 			true, Seed
 			>::value
 	>
-	SPROUT_CXX14_CONSTEXPR void srand() {}
+	inline SPROUT_CXX14_CONSTEXPR void srand() {}
 	template<
 		typename T, unsigned Seed,
 		int N = 1,
@@ -203,7 +203,7 @@ namespace sprout {
 			true, Seed
 			>::value
 	>
-	SPROUT_CONSTEXPR unsigned srand_return() {
+	inline SPROUT_CONSTEXPR unsigned srand_return() {
 		return R;
 	}
 
diff --git a/sprout/stateful/typed_slot.hpp b/sprout/stateful/typed_slot.hpp
index 77c8f85b..32b4c9ce 100644
--- a/sprout/stateful/typed_slot.hpp
+++ b/sprout/stateful/typed_slot.hpp
@@ -108,7 +108,7 @@ namespace sprout {
 		int N = 1,
 		std::intmax_t R = sprout::typed_slot_detail::typed<T>::template val(sprout::true_type(), typename sprout::typed_slot_detail::typed<T>::template tag<N>())
 	>
-	SPROUT_CONSTEXPR std::intmax_t slot() {
+	inline SPROUT_CONSTEXPR std::intmax_t slot() {
 		return R;
 	}
 
@@ -124,7 +124,7 @@ namespace sprout {
 			Value
 			>::value
 	>
-	SPROUT_CXX14_CONSTEXPR void assign_slot() {}
+	inline SPROUT_CXX14_CONSTEXPR void assign_slot() {}
 	template<
 		typename T, std::intmax_t Value,
 		int N = 1,
@@ -133,7 +133,7 @@ namespace sprout {
 			Value
 			>::value
 	>
-	SPROUT_CONSTEXPR std::intmax_t assign_slot_return() {
+	inline SPROUT_CONSTEXPR std::intmax_t assign_slot_return() {
 		return R;
 	}