boost_mp11/doc/mp11/integral.adoc

////
Copyright 2017 Peter Dimov

Distributed under the Boost Software License, Version 1.0.

See accompanying file LICENSE_1_0.txt or copy at
http://www.boost.org/LICENSE_1_0.txt
////

[#integral]
# Integral Constants, <boost/mp11/integral.hpp>
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For an Mp11 integral constant type `T`, `T::value` is an integral constant in the C++ sense.

## mp_bool<B>

    template<bool B> using mp_bool = std::integral_constant<bool, B>;

Same as `std::bool_constant` in C++17.

## mp_true

    using mp_true = mp_bool<true>;

Same as `std::true_type`.

## mp_false

    using mp_false = mp_bool<false>;

Same as `std::false_type`.

## mp_to_bool<T>

    template<class T> using mp_to_bool = mp_bool<static_cast<bool>(T::value)>;

## mp_not<T>

    template<class T> using mp_not = mp_bool< !T::value >;

## mp_int<I>

    template<int I> using mp_int = std::integral_constant<int, I>;

## mp_size_t<N>

    template<std::size_t N> using mp_size_t = std::integral_constant<std::size_t, N>;

## mp_value<A>

    template<auto A> using mp_value = std::integral_constant<decltype(A), A>;

When a value list is converted to a type list, either explicitly via `mp_rename`, or
implicitly by a primitive that supports value lists directly, its values are converted
to types by wrapping then with `mp_value`.

Requires {cpp}17.