993 B
993 B
[meta.help]
21 Metaprogramming library [meta]
21.3 Metaprogramming and type traits [type.traits]
21.3.4 Helper classes [meta.help]
namespace std {template<class T, T v> struct integral_constant {static constexpr T value = v; using value_type = T; using type = integral_constant<T, v>; constexpr operator value_type() const noexcept { return value; }constexpr value_type operator()() const noexcept { return value; }};}
The class template integral_constant, alias template bool_constant, and its associated typedef-namestrue_type and false_type are used as base classes to define the interface for various type traits.