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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/any_of.hpp>
#include <boost/hana/assert.hpp>
#include <boost/hana/bool.hpp>
#include <boost/hana/equal.hpp>
#include <boost/hana/find_if.hpp>
#include <boost/hana/fwd/at.hpp>
#include <boost/hana/fwd/drop_front.hpp>
#include <boost/hana/fwd/is_empty.hpp>
#include <boost/hana/integral_constant.hpp>
#include <boost/hana/optional.hpp>
namespace hana = boost::hana;
// A simple infinite Iterable.
template <int i>
struct counter { };
namespace boost { namespace hana {
template <int i>
struct at_impl<counter<i>> {
template <typename N>
static constexpr auto apply(counter<i>, N const&) {
return hana::int_c<i + N::value>;
}
};
template <int i>
struct drop_front_impl<counter<i>> {
template <typename N>
static constexpr auto apply(counter<i>, N) { return counter<i + N::value>{}; }
};
template <int i>
struct is_empty_impl<counter<i>> {
static constexpr auto apply(counter<i>) { return hana::false_c; }
};
}}
int main() {
// find_if and any_of should short-circuit and stop even though the
// Iterable is infinite.
BOOST_HANA_CONSTANT_CHECK(hana::any_of(counter<1>{}, hana::equal.to(hana::int_c<4>)));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::find_if(counter<1>{}, hana::equal.to(hana::int_c<4>)),
hana::just(hana::int_c<4>)
));
}
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