1 files changed, 34 insertions, 0 deletions
diff --git a/boost/parameter/aux_/preprocessor/impl/parenthesized_type.hpp b/boost/parameter/aux_/preprocessor/impl/parenthesized_type.hpp
new file mode 100644
index 0000000000..f3d9ed9a90
--- /dev/null
+++ b/boost/parameter/aux_/preprocessor/impl/parenthesized_type.hpp
@@ -0,0 +1,34 @@
+// Copyright David Abrahams 2006.
+// 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 BOOST_PARAMETER_AUX_PREPROCESSOR_IMPL_PARENTHESIZED_TYPE_HPP
+#define BOOST_PARAMETER_AUX_PREPROCESSOR_IMPL_PARENTHESIZED_TYPE_HPP
+
+namespace boost { namespace parameter { namespace aux {
+
+    // A metafunction that transforms void(*)(T) -> T
+    template <typename UnaryFunctionPointer>
+    struct unaryfunptr_arg_type;
+
+    template <typename Arg>
+    struct unaryfunptr_arg_type<void(*)(Arg)>
+    {
+        typedef Arg type;
+    };
+
+    template <>
+    struct unaryfunptr_arg_type<void(*)(void)>
+    {
+        typedef void type;
+    };
+}}} // namespace boost::parameter::aux
+
+// A macro that takes a parenthesized C++ type name (T) and transforms it
+// into an un-parenthesized type expression equivalent to T.
+#define BOOST_PARAMETER_PARENTHESIZED_TYPE(x)                                \
+    ::boost::parameter::aux::unaryfunptr_arg_type< void(*)x >::type
+
+#endif  // include guard
+