Implemented `Reverse` function in terms of `Fold`

2 files changed, 25 insertions, 0 deletions

diff --git a/src/list/operation/higher/misc.h b/src/list/operation/higher/misc.h
index 708265a..280c0d5 100644
--- a/src/list/operation/higher/misc.h
+++ b/src/list/operation/higher/misc.h
@@ -2,6 +2,7 @@
 #define TYPEASVALUE_SRC_LIST_OPERATION_HIGHER_MISC_H_
 
 #include "fold.h"
+#include "list/operation/concatenate.h"
 
 namespace tav {
 
@@ -24,6 +25,25 @@ class Map {
 
 };
 
+template <typename List>
+class Reverse {
+	private:
+		template <
+			typename Current,
+			typename Previous
+		>
+		struct ReversedConcatenate {
+			typedef typename Concatenate<
+				Previous,
+				Cons<Current, void>
+			>::type type;
+		};
+
+	public:
+		typedef typename Fold<ReversedConcatenate, void, List>::type type;
+
+};
+
 }
 
 #endif  // TYPEASVALUE_SRC_LIST_OPERATION_HIGHER_MISC_H_
diff --git a/test.cc b/test.cc
index 6b9dffb..655aed3 100644
--- a/test.cc
+++ b/test.cc
@@ -99,6 +99,11 @@ TEST_F(TypeAsValueTest, ListMap) {
 	EXPECT_TRUE(( std::is_same<tav::List<tav::Int<4>, tav::Int<8>, tav::Int<12>>::type, tav::Map<quadruple, tav::List<tav::Int<1>, tav::Int<2>, tav::Int<3>>::type>::type>::value ));
 }
 
+TEST_F(TypeAsValueTest, ListReverse) {
+	// (reverse (list 1 2 3))
+	EXPECT_TRUE(( std::is_same<tav::List<tav::Int<3>, tav::Int<2>, tav::Int<1>>::type, tav::Reverse<tav::List<tav::Int<1>, tav::Int<2>, tav::Int<3>>::type>::type>::value ));
+}
+
 int main(int argc, char **argv) {
 	testing::InitGoogleTest(&argc, argv);