From e3dfa7268aa7ee96bac8aa53a64f3bd7507d9625 Mon Sep 17 00:00:00 2001
From: Douglas Gregor <doug.gregor@gmail.com>
Date: Fri, 5 Sep 2008 14:55:34 +0000
Subject: [PATCH] Add forward-declaration header for Boost.Function. Fixes
 #1668

[SVN r48613]
---
 include/boost/function/function_base.hpp | 32 +----------
 include/boost/function/function_fwd.hpp  | 67 ++++++++++++++++++++++++
 2 files changed, 68 insertions(+), 31 deletions(-)
 create mode 100644 include/boost/function/function_fwd.hpp

diff --git a/include/boost/function/function_base.hpp b/include/boost/function/function_base.hpp
index 8d46711..ea92b25 100644
--- a/include/boost/function/function_base.hpp
+++ b/include/boost/function/function_base.hpp
@@ -30,6 +30,7 @@
 #  include "boost/mpl/bool.hpp"
 #endif
 #include <boost/function_equal.hpp>
+#include <boost/function/function_fwd.hpp>
 
 #if defined(BOOST_MSVC)
 #   pragma warning( push )
@@ -63,21 +64,6 @@
 #  define BOOST_FUNCTION_TARGET_FIX(x)
 #endif // not MSVC
 
-#if defined(__sgi) && defined(_COMPILER_VERSION) && _COMPILER_VERSION <= 730 && !defined(BOOST_STRICT_CONFIG)
-// Work around a compiler bug.
-// boost::python::objects::function has to be seen by the compiler before the
-// boost::function class template.
-namespace boost { namespace python { namespace objects {
-  class function;
-}}}
-#endif
-
-#if defined (BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)                    \
- || defined(BOOST_BCB_PARTIAL_SPECIALIZATION_BUG)                         \
- || !(BOOST_STRICT_CONFIG || !defined(__SUNPRO_CC) || __SUNPRO_CC > 0x540)
-#  define BOOST_FUNCTION_NO_FUNCTION_TYPE_SYNTAX
-#endif
-
 #if !BOOST_WORKAROUND(__BORLANDC__, < 0x600)
 #  define BOOST_FUNCTION_ENABLE_IF_NOT_INTEGRAL(Functor,Type)              \
       typename ::boost::enable_if_c<(::boost::type_traits::ice_not<          \
@@ -92,22 +78,6 @@ namespace boost { namespace python { namespace objects {
                        Type>::type
 #endif
 
-#if !defined(BOOST_FUNCTION_NO_FUNCTION_TYPE_SYNTAX)
-namespace boost {
-
-template<typename Signature>
-class function;
-
-template<typename Signature>
-inline void swap(function<Signature>& f1,
-                 function<Signature>& f2)
-{
-  f1.swap(f2);
-}
-
-} // end namespace boost
-#endif // have partial specialization
-
 namespace boost {
   namespace detail {
     namespace function {
diff --git a/include/boost/function/function_fwd.hpp b/include/boost/function/function_fwd.hpp
new file mode 100644
index 0000000..7a1ad52
--- /dev/null
+++ b/include/boost/function/function_fwd.hpp
@@ -0,0 +1,67 @@
+// Boost.Function library
+//  Copyright (C) Douglas Gregor 2008
+//
+//  Use, modification and distribution is subject to 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)
+//
+// For more information, see http://www.boost.org
+#ifndef BOOST_FUNCTION_FWD_HPP
+#define BOOST_FUNCTION_FWD_HPP
+#include <boost/config.hpp>
+
+#if defined(__sgi) && defined(_COMPILER_VERSION) && _COMPILER_VERSION <= 730 && !defined(BOOST_STRICT_CONFIG)
+// Work around a compiler bug.
+// boost::python::objects::function has to be seen by the compiler before the
+// boost::function class template.
+namespace boost { namespace python { namespace objects {
+  class function;
+}}}
+#endif
+
+#if defined (BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION)                    \
+ || defined(BOOST_BCB_PARTIAL_SPECIALIZATION_BUG)                         \
+ || !(BOOST_STRICT_CONFIG || !defined(__SUNPRO_CC) || __SUNPRO_CC > 0x540)
+#  define BOOST_FUNCTION_NO_FUNCTION_TYPE_SYNTAX
+#endif
+
+namespace boost {
+#if !defined(BOOST_FUNCTION_NO_FUNCTION_TYPE_SYNTAX)
+  // Preferred syntax
+  template<typename Signature> class function;
+
+  template<typename Signature>
+  inline void swap(function<Signature>& f1, function<Signature>& f2)
+  {
+    f1.swap(f2);
+  }
+#endif // have partial specialization
+
+  // Portable syntax
+  template<typename R> class function0;
+  template<typename R, typename T1> class function1;
+  template<typename R, typename T1, typename T2> class function2;
+  template<typename R, typename T1, typename T2, typename T3> class function3;
+  template<typename R, typename T1, typename T2, typename T3, typename T4> 
+    class function4;
+  template<typename R, typename T1, typename T2, typename T3, typename T4,
+           typename T5> 
+    class function5;
+  template<typename R, typename T1, typename T2, typename T3, typename T4,
+           typename T5, typename T6> 
+    class function6;
+  template<typename R, typename T1, typename T2, typename T3, typename T4,
+           typename T5, typename T6, typename T7> 
+    class function7;
+  template<typename R, typename T1, typename T2, typename T3, typename T4,
+           typename T5, typename T6, typename T7, typename T8> 
+    class function8;
+  template<typename R, typename T1, typename T2, typename T3, typename T4,
+           typename T5, typename T6, typename T7, typename T8, typename T9> 
+    class function9;
+  template<typename R, typename T1, typename T2, typename T3, typename T4,
+           typename T5, typename T6, typename T7, typename T8, typename T9,
+           typename T10> 
+    class function10;
+}
+#endif