Fix compilation with standard libraries implementations which use raw pointers as iterators

Add missing friend declaration
Fixes issue #100
2026-01-21 04:52:10 +00:00 · 2026-01-16 11:19:22 +01:00 · 2025-12-22 12:21:01 +01:00 · 2025-12-22 11:53:06 +01:00
3 changed files with 8 additions and 4 deletions
--- a/include/boost/dynamic_bitset/dynamic_bitset.hpp
+++ b/include/boost/dynamic_bitset/dynamic_bitset.hpp
@@ -1426,13 +1426,13 @@ template< typename Iterator >
 class bit_iterator_base
 {
 public:
-    typedef typename Iterator::iterator_category iterator_category;
+    typedef typename std::iterator_traits< Iterator >::iterator_category iterator_category;
    typedef bool                                 value_type;
    typedef std::ptrdiff_t                       difference_type;
    typedef value_type *                         pointer;
    typedef value_type &                         reference;

-    static constexpr int                         bits_per_block = std::numeric_limits< typename Iterator::value_type >::digits;
+    static constexpr int                         bits_per_block = std::numeric_limits< typename std::iterator_traits< Iterator >::value_type >::digits;

    BOOST_DYNAMIC_BITSET_CONSTEXPR20             bit_iterator_base( Iterator block_iterator, int bit_index );

@@ -1440,11 +1440,13 @@ public:
    friend BOOST_DYNAMIC_BITSET_CONSTEXPR20 bool operator==( const bit_iterator_base< Iter > & lhs, const bit_iterator_base< Iter > & rhs );
    template< typename Iter >
    friend BOOST_DYNAMIC_BITSET_CONSTEXPR20 bool operator<( const bit_iterator_base< Iter > & lhs, const bit_iterator_base< Iter > & rhs );
+    template< typename Iter >
+    friend BOOST_DYNAMIC_BITSET_CONSTEXPR20 difference_type operator-( const bit_iterator_base< Iter > & lhs, const bit_iterator_base< Iter > & rhs );

 protected:
    BOOST_DYNAMIC_BITSET_CONSTEXPR20 void increment();
    BOOST_DYNAMIC_BITSET_CONSTEXPR20 void decrement();
-    BOOST_DYNAMIC_BITSET_CONSTEXPR20 void add( typename Iterator::difference_type n );
+    BOOST_DYNAMIC_BITSET_CONSTEXPR20 void add( typename std::iterator_traits< Iterator >::difference_type n );

    Iterator                              m_block_iterator;
    int                                   m_bit_index = 0;
--- a/include/boost/dynamic_bitset/impl/dynamic_bitset.ipp
+++ b/include/boost/dynamic_bitset/impl/dynamic_bitset.ipp
@@ -185,7 +185,7 @@ bit_iterator_base< Iterator >::decrement()

 template< typename Iterator >
 BOOST_DYNAMIC_BITSET_CONSTEXPR20 void
-bit_iterator_base< Iterator >::add( typename Iterator::difference_type n )
+bit_iterator_base< Iterator >::add( typename std::iterator_traits< Iterator >::difference_type n )
 {
    typename Iterator::difference_type d = m_bit_index + n;
    m_block_iterator += d / bits_per_block;
--- a/test/bitset_test.hpp
+++ b/test/bitset_test.hpp
@@ -248,6 +248,8 @@ struct bitset_test
            BOOST_TEST( *( 1 + b.begin() ) == b[ 1 ] );
            BOOST_TEST( *( b.end() - 1 ) == b[ b.size() - 1 ] );
        }
+
+        BOOST_TEST( b.end() - b.begin() == static_cast< std::ptrdiff_t >( b.size() ) );
    }

    static void
Author	SHA1	Message	Date
Yuriy Chernyshov	75d3e4d83d	Fix compilation with standard libraries implementations which use raw pointers as iterators	2026-01-16 11:19:22 +01:00
sehe	9b64641093	Add missing friend declaration Fixes issue #100	2025-12-22 12:21:01 +01:00
Gennaro Prota	54c841d585	Exercise subtraction between iterators in the unit tests Reason: This was missing. And we forgot a friend declaration for the corresponding operator-(), which will be added with the next commit.	2025-12-22 11:53:06 +01:00