mpl::always is now nullary. Test is updated to take care of new possible calls using apply and apply0.

[SVN r71163]

include/boost/mpl/always.hpp

@@ -14,7 +14,7 @@
 // $Date$
 // $Revision$
 
-#include <boost/mpl/aux_/preprocessor/def_params_tail.hpp>
+#include <boost/mpl/aux_/preprocessor/default_params.hpp>
 #include <boost/mpl/aux_/na.hpp>
 #include <boost/mpl/aux_/arity_spec.hpp>
 
@@ -23,8 +23,7 @@ namespace boost { namespace mpl {
 template< typename Value > struct always
 {
     template<
-          typename T
-        BOOST_MPL_PP_NESTED_DEF_PARAMS_TAIL(1, typename T, na)
+        BOOST_MPL_PP_DEFAULT_PARAMS(BOOST_MPL_LIMIT_METAFUNCTION_ARITY, typename T, na)
         >
     struct apply
     {
@@ -32,7 +31,7 @@ template< typename Value > struct always
     };
 };
 
-BOOST_MPL_AUX_ARITY_SPEC(1, always)
+BOOST_MPL_AUX_ARITY_SPEC(0, always)
 
 }}