1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <functional> 11 12 // reference_wrapper 13 14 // Test that reference wrapper meets the requirements of TriviallyCopyable, 15 // CopyConstructible and CopyAssignable. 16 17 #include <functional> 18 #include <type_traits> 19 #include <string> 20 21 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 22 class MoveOnly 23 { 24 MoveOnly(const MoveOnly&); 25 MoveOnly& operator=(const MoveOnly&); 26 27 int data_; 28 public: MoveOnly(int data=1)29 MoveOnly(int data = 1) : data_(data) {} MoveOnly(MoveOnly && x)30 MoveOnly(MoveOnly&& x) 31 : data_(x.data_) {x.data_ = 0;} operator =(MoveOnly && x)32 MoveOnly& operator=(MoveOnly&& x) 33 {data_ = x.data_; x.data_ = 0; return *this;} 34 get() const35 int get() const {return data_;} 36 }; 37 #endif 38 39 40 template <class T> test()41void test() 42 { 43 typedef std::reference_wrapper<T> Wrap; 44 static_assert(std::is_copy_constructible<Wrap>::value, ""); 45 static_assert(std::is_copy_assignable<Wrap>::value, ""); 46 // Extension up for standardization: See N4151. 47 static_assert(std::is_trivially_copyable<Wrap>::value, ""); 48 } 49 main()50int main() 51 { 52 test<int>(); 53 test<double>(); 54 test<std::string>(); 55 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES 56 test<MoveOnly>(); 57 #endif 58 } 59