25 lines
682 B
C++
25 lines
682 B
C++
// Copyright Louis Dionne 2013-2017
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// Distributed under the Boost Software License, Version 1.0.
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// (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
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#include <boost/hana/core/when.hpp>
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namespace hana = boost::hana;
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template <typename T, typename = hana::when<true>>
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struct base_template;
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template <typename T>
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struct base_template<T, hana::when_valid<typename T::first_type>> { };
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template <typename T>
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struct base_template<T, hana::when_valid<typename T::second_type>> { };
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struct First { struct first_type; };
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struct Second { struct second_type; };
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template struct base_template<First>;
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template struct base_template<Second>;
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int main() { }
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