Added copyable reference wrapper.

diff --git a/include/stg/ref.h b/include/stg/ref.h
new file mode 100644 (file)
index 0000000..e1bdb54
--- /dev/null
+++ b/include/stg/ref.h
@@ -0,0 +1,54 @@
+/*
+ *    This program 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 2 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program 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 program; if not, write to the Free Software
+ *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ *    Author : Maxim Mamontov <faust@stargazer.dp.ua>
+ */
+
+namespace STG
+{
+
+// The implementation is derived from
+// http://en.cppreference.com/w/cpp/utility/functional/reference_wrapper
+// and
+// http://en.cppreference.com/w/cpp/memory/addressof
+
+template< class T >
+T* AddressOf(T& arg)
+{
+    return reinterpret_cast<T*>(&const_cast<char&>(reinterpret_cast<const volatile char&>(arg)));
+}
+
+template <class T>
+class RefWrapper {
+    public:
+          typedef T type;
+          RefWrapper(T& ref) throw() : m_ptr(AddressOf(ref)) {}
+          RefWrapper(const RefWrapper& rhs) : m_ptr(rhs.m_ptr) {}
+          RefWrapper& operator=(const RefWrapper& rhs) throw() { m_ptr = rhs.m_ptr; }
+          operator T& () const throw() { return *m_ptr; }
+          T& get() const throw() { return *m_ptr; }
+
+          void operator()() { (*m_ptr)(); }
+          template <typename A>
+          void operator()(A a) { (*m_ptr)(a); }
+          template <typename A1, typename A2>
+          void operator()(A1 a1, A2 a2) { (*m_ptr)(a1, a2); }
+    private:
+          T* m_ptr;
+};
+
+} // namespace STG