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/*=============================================================================
Copyright (c) 2017 Paul Fultz II
filter.cpp
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)
==============================================================================*/
#include <boost/hof/if.hpp>
#include "test.hpp"
#include <boost/hof/proj.hpp>
#include <boost/hof/lift.hpp>
#include <boost/hof/construct.hpp>
#include <boost/hof/first_of.hpp>
#include <boost/hof/unpack.hpp>
#include <tuple>
BOOST_HOF_LIFT_CLASS(make_tuple_f, std::make_tuple);
struct integer_predicate
{
constexpr integer_predicate()
{}
template<class T>
constexpr auto operator()(T x) const BOOST_HOF_RETURNS
(
boost::hof::first_of(
boost::hof::if_(std::is_integral<T>())(boost::hof::pack_basic),
boost::hof::always(boost::hof::pack_basic())
)(boost::hof::move(x))
)
};
struct filter_integers
{
template<class Seq>
constexpr auto operator()(Seq s) const BOOST_HOF_RETURNS
(
boost::hof::unpack(
boost::hof::proj(integer_predicate(), boost::hof::unpack(make_tuple_f()))
)(std::move(s))
)
};
BOOST_HOF_TEST_CASE()
{
BOOST_HOF_TEST_CHECK(filter_integers()(boost::hof::pack_basic(1, 2, 2.0, 3)) == std::make_tuple(1, 2, 3));
#if BOOST_HOF_HAS_CONSTEXPR_TUPLE
BOOST_HOF_STATIC_TEST_CHECK(filter_integers()(boost::hof::pack_basic(1, 2, 2.0, 3)) == std::make_tuple(1, 2, 3));
#endif
}
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