merged from trunk

[SVN r47983]

include/boost/range/as_literal.hpp

@@ -25,7 +25,9 @@
 #include <boost/detail/workaround.hpp>
 
 #include <cstring>
+#ifndef BOOST_NO_CWCHAR 
 #include <cwchar>
+#endif
 
 namespace boost
 {
@@ -36,10 +38,12 @@ namespace boost
             return strlen( s );
         }
 
+#ifndef BOOST_NO_INTRINSIC_WCHAR_T 
         inline std::size_t length( const wchar_t* s )
         {
             return wcslen( s );
         }
+#endif        
 
         //
         // Remark: the compiler cannot choose between T* and T[sz]
@@ -57,7 +61,7 @@ namespace boost
             return true;
         }
 
-        
+#ifndef BOOST_NO_INTRINSIC_WCHAR_T 
         inline bool is_char_ptr( wchar_t* )
         {
             return true;
@@ -67,6 +71,7 @@ namespace boost
         {
             return true;
         }
+#endif
         
         template< class T >
         inline long is_char_ptr( T /* r */ )

include/boost/range/begin.hpp

@@ -73,15 +73,15 @@ namespace range_detail
     // May this be discarded? Or is it needed for bad compilers?
     //
     template< typename T, std::size_t sz >
-    inline const T* range_begin( const T (&array)[sz] )
+    inline const T* range_begin( const T (&a)[sz] )
     {
-        return array;
+        return a;
     }
 
     template< typename T, std::size_t sz >
-    inline T* range_begin( T (&array)[sz] )
+    inline T* range_begin( T (&a)[sz] )
     {
-        return array;
+        return a;
     }
 
 

include/boost/range/end.hpp

@@ -71,15 +71,15 @@ namespace range_detail
         //////////////////////////////////////////////////////////////////////
 
         template< typename T, std::size_t sz >
-        inline const T* range_end( const T (&array)[sz] )
+        inline const T* range_end( const T (&a)[sz] )
         {
-            return range_detail::array_end<T,sz>( array );
+            return range_detail::array_end<T,sz>( a );
         }
 
         template< typename T, std::size_t sz >
-        inline T* range_end( T (&array)[sz] )
+        inline T* range_end( T (&a)[sz] )
         {
-            return range_detail::array_end<T,sz>( array );
+            return range_detail::array_end<T,sz>( a );
         }
 
 #if !BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564)) && \

include/boost/range/iterator_range.hpp

@@ -185,7 +185,7 @@ namespace boost
                 m_Begin(Begin), m_End(End)
                 #ifndef NDEBUG
             , singular(false) 
-                 #endif
+                #endif
             {}
 
             //! Constructor from a Range
@@ -210,7 +210,7 @@ namespace boost
             template< class Range >
             iterator_range( const Range& r, iterator_range_detail::const_range_tag ) : 
                 m_Begin( impl::adl_begin( r ) ), m_End( impl::adl_end( r ) )
-                 #ifndef NDEBUG
+                #ifndef NDEBUG
             , singular(false) 
                 #endif
             {}
@@ -219,7 +219,7 @@ namespace boost
             template< class Range >
             iterator_range( Range& r, iterator_range_detail::range_tag ) : 
                 m_Begin( impl::adl_begin( r ) ), m_End( impl::adl_end( r ) )
-                 #ifndef NDEBUG
+                #ifndef NDEBUG
             , singular(false) 
                 #endif
             {}
@@ -390,13 +390,15 @@ namespace boost
             bool      singular;
             #endif
 
-            #ifndef NDEBUG
         public:
             bool is_singular() const
             {
+                 #ifndef NDEBUG
                  return singular;
+                 #else
+                 return false;
+                 #endif
             }
-            #endif
 
         protected:
             //

include/boost/range/sub_range.hpp

@@ -23,6 +23,8 @@
 #include <boost/range/size_type.hpp>
 #include <boost/range/difference_type.hpp>
 #include <boost/assert.hpp>
+#include <boost/type_traits/is_reference.hpp>
+#include <boost/type_traits/remove_reference.hpp>
 
 namespace boost
 {
@@ -41,6 +43,12 @@ namespace boost
         typedef BOOST_DEDUCED_TYPENAME range_difference<ForwardRange>::type       difference_type;
         typedef BOOST_DEDUCED_TYPENAME range_size<ForwardRange>::type             size_type;
         typedef BOOST_DEDUCED_TYPENAME base::reference                            reference;
+        
+    public: // for return value of front/back
+        typedef BOOST_DEDUCED_TYPENAME 
+                boost::mpl::if_< boost::is_reference<reference>,
+                                 const BOOST_DEDUCED_TYPENAME boost::remove_reference<reference>::type&, 
+                                 reference >::type const_reference;
 
     public:
         sub_range() : base() 
@@ -112,7 +120,7 @@ namespace boost
             return base::front();
         }
 
-        const value_type& front() const
+        const_reference front() const
         {
             return base::front();
         }
@@ -122,7 +130,7 @@ namespace boost
             return base::back();
         }
 
-        const value_type& back() const
+        const_reference back() const
         {
             return base::back();
         }
@@ -132,7 +140,7 @@ namespace boost
             return base::operator[](sz);
         }
 
-        const value_type& operator[]( difference_type sz ) const
+        const_reference operator[]( difference_type sz ) const
         {
             return base::operator[](sz);
         }