| //===----------------------------------------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is dual licensed under the MIT and the University of Illinois Open |
| // Source Licenses. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // type_traits |
| |
| // add_lvalue_reference |
| // If T names a referenceable type then the member typedef type |
| // shall name T&; otherwise, type shall name T. |
| |
| #include <type_traits> |
| #include "test_macros.h" |
| |
| template <class T, class U> |
| void test_add_lvalue_reference() |
| { |
| static_assert((std::is_same<typename std::add_lvalue_reference<T>::type, U>::value), ""); |
| #if TEST_STD_VER > 11 |
| static_assert((std::is_same<std::add_lvalue_reference_t<T>, U>::value), ""); |
| #endif |
| } |
| |
| template <class F> |
| void test_function0() |
| { |
| static_assert((std::is_same<typename std::add_lvalue_reference<F>::type, F&>::value), ""); |
| #if TEST_STD_VER > 11 |
| static_assert((std::is_same<std::add_lvalue_reference_t<F>, F&>::value), ""); |
| #endif |
| } |
| |
| template <class F> |
| void test_function1() |
| { |
| static_assert((std::is_same<typename std::add_lvalue_reference<F>::type, F>::value), ""); |
| #if TEST_STD_VER > 11 |
| static_assert((std::is_same<std::add_lvalue_reference_t<F>, F>::value), ""); |
| #endif |
| } |
| |
| struct Foo {}; |
| |
| int main() |
| { |
| test_add_lvalue_reference<void, void>(); |
| test_add_lvalue_reference<int, int&>(); |
| test_add_lvalue_reference<int[3], int(&)[3]>(); |
| test_add_lvalue_reference<int&, int&>(); |
| test_add_lvalue_reference<const int&, const int&>(); |
| test_add_lvalue_reference<int*, int*&>(); |
| test_add_lvalue_reference<const int*, const int*&>(); |
| test_add_lvalue_reference<Foo, Foo&>(); |
| |
| // LWG 2101 specifically talks about add_lvalue_reference and functions. |
| // The term of art is "a referenceable type", which a cv- or ref-qualified function is not. |
| test_function0<void()>(); |
| #if TEST_STD_VER >= 11 |
| test_function1<void() const>(); |
| test_function1<void() &>(); |
| test_function1<void() &&>(); |
| test_function1<void() const &>(); |
| test_function1<void() const &&>(); |
| #endif |
| |
| // But a cv- or ref-qualified member function *is* "a referenceable type" |
| test_function0<void (Foo::*)()>(); |
| #if TEST_STD_VER >= 11 |
| test_function0<void (Foo::*)() const>(); |
| test_function0<void (Foo::*)() &>(); |
| test_function0<void (Foo::*)() &&>(); |
| test_function0<void (Foo::*)() const &>(); |
| test_function0<void (Foo::*)() const &&>(); |
| #endif |
| } |