1 files changed, 47 insertions, 0 deletions
diff --git a/boost/function_types/detail/to_sequence.hpp b/boost/function_types/detail/to_sequence.hpp
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+++ b/boost/function_types/detail/to_sequence.hpp
@@ -0,0 +1,47 @@
+
+// (C) Copyright Tobias Schwinger
+//
+// Use modification and distribution are subject to the boost Software License,
+// Version 1.0. (See http://www.boost.org/LICENSE_1_0.txt).
+
+//------------------------------------------------------------------------------
+
+#ifndef BOOST_FT_DETAIL_TO_SEQUENCE_HPP_INCLUDED
+#define BOOST_FT_DETAIL_TO_SEQUENCE_HPP_INCLUDED
+
+#include <boost/mpl/eval_if.hpp>
+#include <boost/mpl/identity.hpp>
+#include <boost/mpl/is_sequence.hpp>
+#include <boost/mpl/placeholders.hpp>
+#include <boost/type_traits/add_reference.hpp>
+
+#include <boost/function_types/is_callable_builtin.hpp>
+
+namespace boost { namespace function_types { namespace detail {
+
+// wrap first arguments in components, if callable builtin type
+template<typename T>
+struct to_sequence
+{
+  typedef typename
+   mpl::eval_if
+   < is_callable_builtin<T>
+   , to_sequence< components<T> >
+   , mpl::identity< T >
+   >::type
+  type;
+};
+
+#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
+// reduce template instantiations, if possible
+template<typename T, typename U>
+struct to_sequence< components<T,U> > 
+{
+  typedef typename components<T,U>::types type;
+};
+#endif
+
+} } } // namespace ::boost::function_types::detail
+
+#endif
+