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// Copyright Louis Dionne 2013-2017
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
#include <boost/hana/equal.hpp>
#include <boost/hana/ext/std/tuple.hpp>
#include <boost/hana/mult.hpp>
#include <boost/hana/transform.hpp>
#include <boost/hana/tuple.hpp>
#include <boost/hana/type.hpp>
#include <boost/hana/unpack.hpp>
#include <boost/hana/zip_with.hpp>
#include <tuple>
#include <type_traits>
#include <utility>
namespace hana = boost::hana;
// Basic usage:
static_assert(
hana::zip_with(hana::mult, hana::make_tuple(1, 2, 3, 4), hana::make_tuple(5, 6, 7, 8))
==
hana::make_tuple(5, 12, 21, 32)
, "");
// Example of computing a tuple of all the common types of several tuples:
template<typename... Ts>
using common_tuple_t = typename decltype(
hana::unpack(
hana::zip_with(
hana::metafunction<std::common_type>,
hana::transform(std::declval<Ts>(), hana::decltype_)...
),
hana::template_<std::tuple>
)
)::type;
static_assert(std::is_same<
common_tuple_t<
std::tuple<bool, int, unsigned>,
std::tuple<char, long, long>,
std::tuple<int, long long, double>
>,
std::tuple<int, long long, double>
>::value, "");
int main() { }
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