1[#metaprogramming_value] 2[section Template metaprogramming value] 3 4A ['template metaprogramming value] is a 5[link nullary_metafunction nullary template metafunction] returning itself. 6For example: 7 8 struct void_ 9 { 10 using type = void_; 11 }; 12 13This template metaprogramming value is called `void_`. It is a nullary 14metafunction returning itself as its result. Because of this, it can be treated 15as a nullary metafunction and evaluated any number of times. For example 16`void_::type::type::type` is still `void_`. 17 18[endsect] 19 20