From e593f875596a86a93cc54b3ac18b88e146b310b1 Mon Sep 17 00:00:00 2001
From: bolero-MURAKAMI <bolero.murakami@gmail.com>
Date: Tue, 6 May 2014 18:10:06 +0900
Subject: [PATCH] add pass_through utility function

---
 example/hanoi/main.cpp           |  1 -
 sprout/utility/operation_ext.hpp |  1 +
 sprout/utility/pass_through.hpp  | 24 ++++++++++++++++++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 sprout/utility/pass_through.hpp

diff --git a/example/hanoi/main.cpp b/example/hanoi/main.cpp
index 4637fb60..f56219ac 100644
--- a/example/hanoi/main.cpp
+++ b/example/hanoi/main.cpp
@@ -13,7 +13,6 @@
 #include <sprout/operation/append_back.hpp>
 #include <sprout/integer/static_pow.hpp>
 #include <sprout/type_traits/enabler_if.hpp>
-#include <sprout/workaround/std/cstddef.hpp>
 
 //
 // hanoi
diff --git a/sprout/utility/operation_ext.hpp b/sprout/utility/operation_ext.hpp
index dda2f607..4e1cd07d 100644
--- a/sprout/utility/operation_ext.hpp
+++ b/sprout/utility/operation_ext.hpp
@@ -13,6 +13,7 @@
 #include <sprout/utility/as_lvalue.hpp>
 #include <sprout/utility/as_const.hpp>
 #include <sprout/utility/lvalue_forward.hpp>
+#include <sprout/utility/pass_through.hpp>
 #include <sprout/utility/limited.hpp>
 
 #endif	// #ifndef SPROUT_UTILITY_OPERATION_EXT_HPP
diff --git a/sprout/utility/pass_through.hpp b/sprout/utility/pass_through.hpp
new file mode 100644
index 00000000..b18ad0be
--- /dev/null
+++ b/sprout/utility/pass_through.hpp
@@ -0,0 +1,24 @@
+/*=============================================================================
+  Copyright (c) 2011-2014 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_PASS_THROUGH_HPP
+#define SPROUT_UTILITY_PASS_THROUGH_HPP
+
+#include <sprout/config.hpp>
+
+namespace sprout {
+	//
+	// pass_through
+	//
+	template<typename T>
+	constexpr T&&
+	pass_through(T&& t) {
+		return static_cast<T&&>(t);
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_MATH_ACOS_HPP