c++ - Looking for a metafunction from bool to bool_type -

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basically, looking library solution this:

#include <boost/type_traits.hpp>  template<bool> struct bool_to_bool_type;  template<> struct bool_to_bool_type<false> {     typedef boost::false_type type; };  template<> struct bool_to_bool_type<true> {     typedef boost::true_type type; };

is there such metafunction?

boost already provides boost::mpl::bool_<>:

boost.typetraits uses integral_constant:

boost_static_assert((      is_same< integral_constant<bool, false>,               is_class<int>::type >::value ));

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