 cds::container::EllenBinTreeSet< GC, Key, T, Traits >         {             typedef cds::container::EllenBinTreeSet< GC, Key, T, Traits > base_class;             template <typename GC0> friend struct EllenBinTreePQueue_pop_max;             template <typename GC0> friend struct EllenBinTreePQueue_pop_min;          public:             typedef T value_type;              bool push( value_type const& val )             {                 return base_class::insert( val );             }              bool pop( value_type& dest )             {                 return Max ? 