hana/example/drop_back.cpp
2017-01-07 14:14:18 -08:00

24 lines
929 B
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/drop_back.hpp>
#include <boost/hana/equal.hpp>
#include <boost/hana/integral_constant.hpp>
#include <boost/hana/tuple.hpp>
namespace hana = boost::hana;
constexpr auto xs = hana::make_tuple(0, '1', 2.0);
static_assert(hana::drop_back(xs, hana::size_c<0>) == xs, "");
static_assert(hana::drop_back(xs, hana::size_c<1>) == hana::make_tuple(0, '1'), "");
static_assert(hana::drop_back(xs, hana::size_c<2>) == hana::make_tuple(0), "");
BOOST_HANA_CONSTANT_CHECK(hana::drop_back(xs, hana::size_c<3>) == hana::make_tuple());
BOOST_HANA_CONSTANT_CHECK(hana::drop_back(xs, hana::size_c<4>) == hana::make_tuple());
static_assert(hana::drop_back(xs) == hana::make_tuple(0, '1'), "");
int main() { }