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

20 lines
483 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/core/when.hpp>
#include <type_traits>
namespace hana = boost::hana;
template <typename T, typename = hana::when<true>>
struct base_template;
template <typename T>
struct base_template<T, hana::when_valid<typename T::value_type>> {
// something useful...
};
int main() { }