| 1 | // Copyright Louis Dionne 2013-2022 |
|---|---|
| 2 | // Distributed under the Boost Software License, Version 1.0. |
| 3 | // (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) |
| 4 | |
| 5 | #include <boost/hana/functional/placeholder.hpp> |
| 6 | namespace hana = boost::hana; |
| 7 | |
| 8 | |
| 9 | constexpr auto plus = hana::_ + hana::_; |
| 10 | static_assert(plus(1, 2) == 1 + 2, ""); |
| 11 | |
| 12 | constexpr auto increment = hana::_ + 1; |
| 13 | static_assert(increment(1) == 2, ""); |
| 14 | |
| 15 | constexpr auto twice = 2 * hana::_; |
| 16 | static_assert(twice(1) == 2, ""); |
| 17 | |
| 18 | // Extra arguments are ignored. |
| 19 | static_assert(twice(1, "ignored") == 2, ""); |
| 20 | |
| 21 | int main() { } |
| 22 |