comparison DEPENDENCIES/generic/include/boost/variant/visitor_ptr.hpp @ 16:2665513ce2d3

Add boost headers

+//-----------------------------------------------------------------------------
+// boost variant/visitor_ptr.hpp header file
+// See http://www.boost.org for updates, documentation, and revision history.
+//-----------------------------------------------------------------------------
+//
+// Copyright (c) 2002-2003
+// Eric Friedman
+//
+// 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_VARIANT_VISITOR_PTR_HPP
+#define BOOST_VARIANT_VISITOR_PTR_HPP
+
+#include "boost/variant/bad_visit.hpp"
+#include "boost/variant/static_visitor.hpp"
+
+#include "boost/mpl/eval_if.hpp"
+#include "boost/mpl/identity.hpp"
+#include "boost/throw_exception.hpp"
+#include "boost/type_traits/add_reference.hpp"
+#include "boost/type_traits/is_reference.hpp"
+#include "boost/type_traits/is_void.hpp"
+
+namespace boost {
+
+//////////////////////////////////////////////////////////////////////////
+// function template visitor_ptr
+//
+// Adapts a function pointer for use as visitor capable of handling
+// values of a single type. Throws bad_visit if inappropriately applied.
+//
+template <typename T, typename R>
+class visitor_ptr_t
+    : public static_visitor<R>
+{
+private: // representation
+
+    typedef R (*visitor_t)(T);
+
+    visitor_t visitor_;
+
+public: // typedefs
+
+    typedef R result_type;
+
+private: // private typedefs
+
+    typedef typename mpl::eval_if<
+          is_reference<T>
+        , mpl::identity<T>
+        , add_reference<const T>
+        >::type argument_fwd_type;
+
+public: // structors
+
+    explicit visitor_ptr_t(visitor_t visitor)
+      : visitor_(visitor)
+    {
+    }
+
+public: // static visitor interfaces
+
+    template <typename U>
+    result_type operator()(const U&) const
+    {
+        boost::throw_exception(bad_visit());
+    }
+
+#if !defined(BOOST_NO_VOID_RETURNS)
+
+public: // static visitor interfaces, cont.
+
+    result_type operator()(argument_fwd_type operand) const
+    {
+        return visitor_(operand);
+    }
+
+#else // defined(BOOST_NO_VOID_RETURNS)
+
+private: // helpers, for static visitor interfaces (below)
+
+    result_type execute_impl(argument_fwd_type operand, mpl::false_) const
+    {
+        return visitor_(operand);
+    }
+
+        BOOST_VARIANT_AUX_RETURN_VOID_TYPE
+    execute_impl(argument_fwd_type operand, mpl::true_) const
+    {
+        visitor_(operand);
+        BOOST_VARIANT_AUX_RETURN_VOID;
+    }
+
+public: // static visitor interfaces, cont.
+
+        BOOST_VARIANT_AUX_GENERIC_RESULT_TYPE(result_type)
+    operator()(argument_fwd_type operand) const
+    {
+        typedef typename is_void<result_type>::type has_void_result;
+        return execute_impl(operand, has_void_result());
+    }
+
+#endif // BOOST_NO_VOID_RETURNS workaround
+
+};
+
+template <typename R, typename T>
+inline visitor_ptr_t<T,R> visitor_ptr(R (*visitor)(T))
+{
+    return visitor_ptr_t<T,R>(visitor);
+}
+
+} // namespace boost
+
+#endif// BOOST_VISITOR_VISITOR_PTR_HPP