hana/test/experimental/view/sliced/is_empty.cpp
2017-01-07 14:14:18 -08:00

50 lines
1.7 KiB
C++

// 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/experimental/view.hpp>
#include <boost/hana/is_empty.hpp>
#include <boost/hana/not.hpp>
#include <boost/hana/tuple.hpp>
#include <support/seq.hpp>
namespace hana = boost::hana;
template <int> struct undefined { };
int main() {
auto container = ::seq;
{
auto storage = container();
auto sliced = hana::experimental::sliced(storage, hana::tuple_c<int>);
BOOST_HANA_CONSTANT_CHECK(hana::is_empty(sliced));
}{
auto storage = container(undefined<0>{});
auto sliced = hana::experimental::sliced(storage, hana::tuple_c<int>);
BOOST_HANA_CONSTANT_CHECK(hana::is_empty(sliced));
}{
auto storage = container(undefined<0>{}, undefined<1>{});
auto sliced = hana::experimental::sliced(storage, hana::tuple_c<int>);
BOOST_HANA_CONSTANT_CHECK(hana::is_empty(sliced));
}
{
auto storage = container(undefined<0>{});
auto sliced = hana::experimental::sliced(storage, hana::tuple_c<int, 0>);
BOOST_HANA_CONSTANT_CHECK(hana::not_(hana::is_empty(sliced)));
}{
auto storage = container(undefined<0>{});
auto sliced = hana::experimental::sliced(storage, hana::tuple_c<int, 0, 0>);
BOOST_HANA_CONSTANT_CHECK(hana::not_(hana::is_empty(sliced)));
}
{
auto storage = container(undefined<0>{}, undefined<1>{});
auto sliced = hana::experimental::sliced(storage, hana::tuple_c<int, 0, 1>);
BOOST_HANA_CONSTANT_CHECK(hana::not_(hana::is_empty(sliced)));
}
}