_impl< na,na > {     template< typename U0, typename U0 > struct apply     {         typedef apply type;         BOOST_STATIC_CONSTANT(int, value  = 0);     }; };  template<> struct less_equal_impl< na,integral_c_tag > {     template< typename U0, typename U0 > struct apply     {         typedef apply type;         BOOST_STATIC_CONSTANT(int, value  = 0);     }; };  template<> struct less_equal_impl< integral_c_tag,na > {     template< typename U0, typename U0 > struct apply     {         typedef apply type;         BOOST_STATIC_CONSTANT(int, value  = 0);     }; };  template< typename T > struct 