From 8408cc0bd5c78bb3f2c2f47a49a18dafcfabb7ec Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jaakko=20J=C3=A4rvi?= <jarvi@cs.tamu.edu>
Date: Fri, 16 Nov 2001 23:27:08 +0000
Subject: [PATCH] thomas witt:s patch for icl501, adds a workaround for
 explicitly qualified arguments Also fixed length, so that it now works for
 empty tuples as well

[SVN r11722]
---
 include/boost/tuple/detail/tuple_basic.hpp    | 29 +++++++++++----
 .../detail/tuple_basic_no_partial_spec.hpp    | 37 ++++++++++++++-----
 2 files changed, 50 insertions(+), 16 deletions(-)

diff --git a/include/boost/tuple/detail/tuple_basic.hpp b/include/boost/tuple/detail/tuple_basic.hpp
index 5b555b3..5f73253 100644
--- a/include/boost/tuple/detail/tuple_basic.hpp
+++ b/include/boost/tuple/detail/tuple_basic.hpp
@@ -67,6 +67,17 @@ template<class T> struct length;
 
 namespace detail {
 
+#ifdef BOOST_NO_EXPLICIT_FUNCTION_TEMPLATE_ARGUMENTS
+
+  template<int N> struct workaround_holder {};
+
+#  define BOOST_TUPLE_DUMMY_PARM        , detail::workaround_holder<N>* = 0
+#  define BOOST_TUPLE_SINGLE_DUMMY_PARM detail::workaround_holder<N>* = 0
+#else
+#  define BOOST_TUPLE_DUMMY_PARM
+#  define BOOST_TUPLE_SINGLE_DUMMY_PARM
+#endif
+
 // -- generate error template, referencing to non-existing members of this 
 // template is used to produce compilation errors intentionally
 template<class T>
@@ -196,7 +207,7 @@ template<int N, class HT, class TT>
 inline typename access_traits<
                   typename element<N, cons<HT, TT> >::type
                 >::non_const_type
-get(cons<HT, TT>& c) { 
+get(cons<HT, TT>& c BOOST_TUPLE_DUMMY_PARM) { 
   return detail::get_class<N>::template 
          get<
            typename access_traits<
@@ -211,7 +222,7 @@ template<int N, class HT, class TT>
 inline typename access_traits<
                   typename element<N, cons<HT, TT> >::type
                 >::const_type
-get(const cons<HT, TT>& c) { 
+get(const cons<HT, TT>& c BOOST_TUPLE_DUMMY_PARM) { 
   return detail::get_class<N>::template 
          get<
            typename access_traits<
@@ -219,9 +230,6 @@ get(const cons<HT, TT>& c) {
          >::const_type>(c);
 } 
 
-
-
-
 // -- the cons template  --------------------------------------------------
 
 template <class HT, class TT>
@@ -346,7 +354,7 @@ struct cons<HT, null_type> {
   typename access_traits<
              typename element<N, cons>::type
             >::non_const_type
-  get() {
+  get(BOOST_TUPLE_SINGLE_DUMMY_PARM) {
     return boost::tuples::get<N>(*this);
   }
 
@@ -354,7 +362,7 @@ struct cons<HT, null_type> {
   typename access_traits<
              typename element<N, cons>::type
            >::const_type
-  get() const {
+  get(BOOST_TUPLE_SINGLE_DUMMY_PARM) const {
     return boost::tuples::get<N>(*this);
   }
 
@@ -367,6 +375,11 @@ struct length  {
   BOOST_STATIC_CONSTANT(int, value = 1 + length<typename T::tail_type>::value);
 };
 
+template<>
+struct length<tuple<> > {
+  BOOST_STATIC_CONSTANT(int, value = 0);
+};
+
 template<>
 struct length<null_type> {
   BOOST_STATIC_CONSTANT(int, value = 0);
@@ -753,6 +766,8 @@ tie(T1& t1, T2& t2, T3& t3, T4& t4, T5& t5, T6& t6, T7& t7, T8& t8,
 } // end of namespace tuples
 } // end of namespace boost
 
+#undef BOOST_TUPLE_DUMMY_PARM
+#undef BOOST_TUPLE_SINGLE_DUMMY_PARM
 
 #endif	// BOOST_TUPLE_BASIC_HPP
 
diff --git a/include/boost/tuple/detail/tuple_basic_no_partial_spec.hpp b/include/boost/tuple/detail/tuple_basic_no_partial_spec.hpp
index f98ed61..3c66360 100644
--- a/include/boost/tuple/detail/tuple_basic_no_partial_spec.hpp
+++ b/include/boost/tuple/detail/tuple_basic_no_partial_spec.hpp
@@ -53,6 +53,21 @@ namespace tuples {
     // a helper function to provide a const null_type type temporary
     inline const null_type cnull_type() { return null_type(); }
 
+// forward declaration of tuple
+    template<
+      typename T1 = null_type, 
+      typename T2 = null_type, 
+      typename T3 = null_type, 
+      typename T4 = null_type,
+      typename T5 = null_type,
+      typename T6 = null_type,
+      typename T7 = null_type,
+      typename T8 = null_type,
+      typename T9 = null_type,
+      typename T10 = null_type
+    >
+    class tuple;
+
     namespace detail {
 
       // Takes a pointer and routes all assignments to whatever it points to
@@ -263,6 +278,10 @@ namespace tuples {
     {
       BOOST_STATIC_CONSTANT(int, value = 1 + length<typename Tuple::tail_type>::value);
     };
+    
+    template<> struct length<tuple<> > {
+      BOOST_STATIC_CONSTANT(int, value = 0);
+    };
 
     template<>
     struct length<null_type>
@@ -318,15 +337,15 @@ namespace tuples {
     // tuple class
     template<
       typename T1, 
-      typename T2 = null_type, 
-      typename T3 = null_type, 
-      typename T4 = null_type,
-      typename T5 = null_type,
-      typename T6 = null_type,
-      typename T7 = null_type,
-      typename T8 = null_type,
-      typename T9 = null_type,
-      typename T10 = null_type
+      typename T2, 
+      typename T3, 
+      typename T4,
+      typename T5,
+      typename T6,
+      typename T7,
+      typename T8,
+      typename T9,
+      typename T10
     >
     class tuple : 
       public detail::map_tuple_to_cons<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10>::cons1