From de1f1dc67a1dabcddac2e89a5d703e98a92b7f11 Mon Sep 17 00:00:00 2001
From: Adrian Kummerlaender
Date: Fri, 20 Feb 2015 22:03:19 +0100
Subject: Added `ReplaceNth` list operation * as its name implies this function
 replaces the _nth_ element of a given list * added appropriate test case

---
 src/list/operation/delete.h      |  4 ++--
 src/list/operation/delete_nth.h  |  6 +++---
 src/list/operation/replace_nth.h | 23 +++++++++++++++++++++++
 test.cc                          | 15 +++++++++++++++
 4 files changed, 43 insertions(+), 5 deletions(-)
 create mode 100644 src/list/operation/replace_nth.h

diff --git a/src/list/operation/delete.h b/src/list/operation/delete.h
index 48f1137..5ac620a 100644
--- a/src/list/operation/delete.h
+++ b/src/list/operation/delete.h
@@ -9,11 +9,11 @@ namespace tav {
 
 template <
 	typename Element,
-	typename List
+	typename Sequence
 >
 using Delete = Remove<
 	Apply<IsEqualValue, _0, Element>::template function,
-	List
+	Sequence
 >;
 
 }
diff --git a/src/list/operation/delete_nth.h b/src/list/operation/delete_nth.h
index 18e52bf..a834150 100644
--- a/src/list/operation/delete_nth.h
+++ b/src/list/operation/delete_nth.h
@@ -9,11 +9,11 @@ namespace tav {
 
 template <
 	typename Index,
-	typename List
+	typename Sequence
 >
 using DeleteNth = Append<
-	Take<Index, List>,
-	Drop<Add<Index, Size<1>>, List>
+	Take<Index, Sequence>,
+	Drop<Add<Index, Size<1>>, Sequence>
 >;
 
 }
diff --git a/src/list/operation/replace_nth.h b/src/list/operation/replace_nth.h
new file mode 100644
index 0000000..519a040
--- /dev/null
+++ b/src/list/operation/replace_nth.h
@@ -0,0 +1,23 @@
+#ifndef TYPEASVALUE_SRC_LIST_OPERATION_REPLACE_NTH_H_
+#define TYPEASVALUE_SRC_LIST_OPERATION_REPLACE_NTH_H_
+
+#include "list/operation/concatenate.h"
+#include "list/operation/take.h"
+#include "list/operation/drop.h"
+
+namespace tav {
+
+template <
+	typename Index,
+	typename Value,
+	typename Sequence
+>
+using ReplaceNth = Concatenate<List<
+	Take<Index, Sequence>,
+	List<Value>,
+	Drop<Add<Index, Size<1>>, Sequence>
+>>;
+
+}
+
+#endif  // TYPEASVALUE_SRC_LIST_OPERATION_REPLACE_NTH_H_
diff --git a/test.cc b/test.cc
index 7a2e963..774f9be 100644
--- a/test.cc
+++ b/test.cc
@@ -22,6 +22,7 @@
 #include "list/generator/higher/list_tabulate.h"
 #include "list/operation/delete.h"
 #include "list/operation/delete_nth.h"
+#include "list/operation/replace_nth.h"
 
 #include "function/apply.h"
 
@@ -666,6 +667,20 @@ static_assert(
 	"(delete-nth 1 (list 1 2 3)) != (list 1 3)"
 );
 
+// list replace nth
+
+static_assert(
+	std::is_same<
+		tav::List<tav::Int<1>, tav::Int<42>, tav::Int<3>>,
+		tav::ReplaceNth<
+			tav::Size<1>,
+			tav::Int<42>,
+			tav::List<tav::Int<1>, tav::Int<2>, tav::Int<3>>
+		>
+	>::value,
+	"(replace-nth 1 42 (list 1 2 3)) != (list 1 42 3)"
+);
+
 // list partition
 
 static_assert(
-- 
cgit v1.2.3