Imported existing code

libraries/include/boost/python/detail/decref_guard.hpp

@@ -0,0 +1,21 @@
+// Copyright David Abrahams 2002.
+// 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 DECREF_GUARD_DWA20021220_HPP
+# define DECREF_GUARD_DWA20021220_HPP
+
+namespace boost { namespace python { namespace detail { 
+
+struct decref_guard
+{
+    decref_guard(PyObject* o) : obj(o) {}
+    ~decref_guard() { Py_XDECREF(obj); }
+    void cancel() { obj = 0; }
+ private:
+    PyObject* obj;
+};
+
+}}} // namespace boost::python::detail
+
+#endif // DECREF_GUARD_DWA20021220_HPP