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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/assert.hpp>
#include <boost/hana/chain.hpp>
#include <boost/hana/equal.hpp>
#include <boost/hana/optional.hpp>
#include <laws/base.hpp>
#include <support/tracked.hpp>
namespace hana = boost::hana;
using hana::test::ct_eq;
struct undefined { };
int main() {
hana::test::_injection<0> f{};
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::sfinae(f)(),
hana::just(f())
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::sfinae(f)(ct_eq<0>{}),
hana::just(f(ct_eq<0>{}))
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::sfinae(f)(ct_eq<0>{}, ct_eq<1>{}),
hana::just(f(ct_eq<0>{}, ct_eq<1>{}))
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::sfinae(undefined{})(),
hana::nothing
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::sfinae(undefined{})(ct_eq<0>{}),
hana::nothing
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
hana::sfinae(undefined{})(ct_eq<0>{}, ct_eq<1>{}),
hana::nothing
));
auto incr = hana::sfinae([](auto x) -> decltype(x + 1) {
return x + 1;
});
BOOST_HANA_RUNTIME_CHECK(hana::equal(
incr(1),
hana::just(2)
));
BOOST_HANA_CONSTANT_CHECK(hana::equal(
incr(undefined{}),
hana::nothing
));
BOOST_HANA_RUNTIME_CHECK(hana::equal(
hana::chain(hana::just(1), incr),
hana::just(2)
));
// using `sfinae` with a non-pod argument used to fail
hana::sfinae(undefined{})(Tracked{1});
hana::sfinae([t = Tracked{1}](auto) { return 1; })(Tracked{1});
}
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