--- /dev/null
+// -*- C++ -*-
+
+// Copyright (C) 2005, 2006, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library is free
+// software; you can redistribute it and/or modify it under the terms
+// of the GNU General Public License as published by the Free Software
+// Foundation; either version 3, or (at your option) any later
+// version.
+
+// This library is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+
+// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
+
+// Permission to use, copy, modify, sell, and distribute this software
+// is hereby granted without fee, provided that the above copyright
+// notice appears in all copies, and that both that copyright notice
+// and this permission notice appear in supporting documentation. None
+// of the above authors, nor IBM Haifa Research Laboratories, make any
+// representation about the suitability of this software for any
+// purpose. It is provided "as is" without express or implied
+// warranty.
+
+/**
+ * @file to_string.hpp
+ * Contains classes for transforming stuff to strings.
+ */
+
+#ifndef PB_DS_REGRESSION_TEST_TO_STRING_HPP
+#define PB_DS_REGRESSION_TEST_TO_STRING_HPP
+
+#include <regression/basic_type.hpp>
+#include <string>
+
+namespace __gnu_pbds
+{
+
+ namespace test
+ {
+
+ namespace detail
+ {
+
+ std::string
+ to_string(const basic_type& r_t)
+ {
+ return (r_t);
+ }
+
+ std::string
+ to_string(const std::string& r_t)
+ {
+ return (r_t);
+ }
+
+ template<typename Hd, class Tl>
+ std::string
+ to_string(const std::pair<Hd, Tl>&r_t)
+ {
+ std::ostringstream ret;
+
+ ret << to_string(r_t.first) << " " << to_string(r_t.second);
+
+ return (ret.str());
+ }
+
+ } // namespace detail
+
+ } // namespace test
+
+} // namespace __gnu_pbds
+
+#endif // #ifndef PB_DS_REGRESSION_TEST_TO_STRING_HPP