| 1 | // Copyright Louis Dionne 2013-2022 |
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| 2 | // Distributed under the Boost Software License, Version 1.0. |
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| 3 | // (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt) |
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| 4 | |
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| 5 | #include <boost/hana/detail/wrong.hpp> |
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| 6 | namespace hana = boost::hana; |
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| 7 | |
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| 8 | |
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| 9 | template <typename T, typename U> |
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| 10 | struct base_template { |
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| 11 | // Can't write this because the assertion would always fire up: |
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| 12 | // static_assert(false, "..."); |
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| 13 | |
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| 14 | // So instead we write this: |
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| 15 | static_assert(hana::detail::wrong<base_template<T, U>>::value, |
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| 16 | "base_template does not have a valid default definition" ); |
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| 17 | }; |
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| 18 | |
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| 19 | template <> |
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| 20 | struct base_template<int, int> { |
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| 21 | // something useful |
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| 22 | }; |
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| 23 | |
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| 24 | int main() { } |
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| 25 | |
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