30 lines
1.1 KiB
C++
30 lines
1.1 KiB
C++
#pragma once
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#include <type_traits> // std::enable_if
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namespace ipc {
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// concept helpers
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template <bool Cond, typename R = void>
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using require = typename std::enable_if<Cond, R>::type;
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#ifdef IPC_CONCEPT_
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# error "IPC_CONCEPT_ has been defined."
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#endif
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#define IPC_CONCEPT_(NAME, WHAT) \
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template <typename T> \
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class NAME { \
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private: \
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template <typename Type> \
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static std::true_type check(decltype(std::declval<Type>().WHAT)*); \
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template <typename Type> \
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static std::false_type check(...); \
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public: \
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using type = decltype(check<T>(nullptr)); \
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constexpr static auto value = type::value; \
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}
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} // namespace ipc
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