adjacent_filtered_range::m_pred should be removed

[iorate]

boost::range_detail::adjacent_filtered_range<P, R, default_pass>::m_pred is not only unused, but also inhibits instantiation of the class when P is not default constructible.

rng | boost::adaptors::adjacent_filtered(std::not2(pred)); // error

I think m_pred and m_range (which is also unused) should be removed.

adjacent_filtered.hpp

@@ -143 +143 @@
                          skip_iter(boost::end(r), boost::end(r), p))
             {
             }
-
-        private:
-            P m_pred;
-            R* m_range;
         };
 
         template< class T >

(When P is not default constructible, the instance of skip_iterator is degraded to an input iterator, but the same goes for filter_iterator.)

In case m_pred is not removed, the reference of adjacent_filtered should be modified.

Change:

Throws: Whatever the copy constructor of bi_pred might throw.

To:

Throws: Whatever the copy constructor and default constructor of bi_pred might throw.

[Neil Groves]

Thank you for the report. The offending unnecessary variables have been removed. The change has been committed to the trunk, and a suitable level of shame felt!