diff options
| -rw-r--r-- | include/type_traits | 62 | ||||
| -rw-r--r-- | test/std/utilities/meta/meta.unary/meta.unary.prop/is_constructible.pass.cpp | 12 |
2 files changed, 70 insertions, 4 deletions
diff --git a/include/type_traits b/include/type_traits index 7a6c992930e4..eb443ee0abd6 100644 --- a/include/type_traits +++ b/include/type_traits @@ -3172,6 +3172,14 @@ template <class _A0, class _A1> false_type __is_constructible2_test(__any, _A0&, _A1&); +template <class _Tp, class _A0, class _A1, class _A2> +decltype((_Tp(_VSTD::declval<_A0>(), _VSTD::declval<_A1>(), _VSTD::declval<_A2>()), true_type())) +__is_constructible3_test(_Tp&, _A0&, _A1&, _A2&); + +template <class _A0, class _A1, class _A2> +false_type +__is_constructible3_test(__any, _A0&, _A1&, _A2&); + template <bool, class _Tp> struct __is_constructible0_imp // false, _Tp is not a scalar : public common_type @@ -3196,6 +3204,14 @@ struct __is_constructible2_imp // false, _Tp is not a scalar >::type {}; +template <bool, class _Tp, class _A0, class _A1, class _A2> +struct __is_constructible3_imp // false, _Tp is not a scalar + : public common_type + < + decltype(__is_constructible3_test(declval<_Tp&>(), declval<_A0>(), declval<_A1>(), declval<_A2>())) + >::type + {}; + // handle scalars and reference types // Scalars are default constructible, references are not @@ -3215,6 +3231,11 @@ struct __is_constructible2_imp<true, _Tp, _A0, _A1> : public false_type {}; +template <class _Tp, class _A0, class _A1, class _A2> +struct __is_constructible3_imp<true, _Tp, _A0, _A1, _A2> + : public false_type + {}; + // Treat scalars and reference types separately template <bool, class _Tp> @@ -3235,6 +3256,12 @@ struct __is_constructible2_void_check _Tp, _A0, _A1> {}; +template <bool, class _Tp, class _A0, class _A1, class _A2> +struct __is_constructible3_void_check + : public __is_constructible3_imp<is_scalar<_Tp>::value || is_reference<_Tp>::value, + _Tp, _A0, _A1, _A2> + {}; + // If any of T or Args is void, is_constructible should be false template <class _Tp> @@ -3252,17 +3279,24 @@ struct __is_constructible2_void_check<true, _Tp, _A0, _A1> : public false_type {}; +template <class _Tp, class _A0, class _A1, class _A2> +struct __is_constructible3_void_check<true, _Tp, _A0, _A1, _A2> + : public false_type + {}; + // is_constructible entry point template <class _Tp, class _A0 = __is_construct::__nat, - class _A1 = __is_construct::__nat> + class _A1 = __is_construct::__nat, + class _A2 = __is_construct::__nat> struct _LIBCPP_TEMPLATE_VIS is_constructible - : public __is_constructible2_void_check<is_void<_Tp>::value + : public __is_constructible3_void_check<is_void<_Tp>::value || is_abstract<_Tp>::value || is_function<_Tp>::value || is_void<_A0>::value - || is_void<_A1>::value, - _Tp, _A0, _A1> + || is_void<_A1>::value + || is_void<_A2>::value, + _Tp, _A0, _A1, _A2> {}; template <class _Tp> @@ -3282,6 +3316,16 @@ struct _LIBCPP_TEMPLATE_VIS is_constructible<_Tp, _A0, __is_construct::__nat> _Tp, _A0> {}; +template <class _Tp, class _A0, class _A1> +struct _LIBCPP_TEMPLATE_VIS is_constructible<_Tp, _A0, _A1, __is_construct::__nat> + : public __is_constructible2_void_check<is_void<_Tp>::value + || is_abstract<_Tp>::value + || is_function<_Tp>::value + || is_void<_A0>::value + || is_void<_A1>::value, + _Tp, _A0, _A1> + {}; + // Array types are default constructible if their element type // is default constructible @@ -3300,6 +3344,11 @@ struct __is_constructible2_imp<false, _Ap[_Np], _A0, _A1> : public false_type {}; +template <class _Ap, size_t _Np, class _A0, class _A1, class _A2> +struct __is_constructible3_imp<false, _Ap[_Np], _A0, _A1, _A2> + : public false_type + {}; + // Incomplete array types are not constructible template <class _Ap> @@ -3317,6 +3366,11 @@ struct __is_constructible2_imp<false, _Ap[], _A0, _A1> : public false_type {}; +template <class _Ap, class _A0, class _A1, class _A2> +struct __is_constructible3_imp<false, _Ap[], _A0, _A1, _A2> + : public false_type + {}; + #endif // __has_feature(is_constructible) diff --git a/test/std/utilities/meta/meta.unary/meta.unary.prop/is_constructible.pass.cpp b/test/std/utilities/meta/meta.unary/meta.unary.prop/is_constructible.pass.cpp index 1f7c32a8cc07..b90363a5c380 100644 --- a/test/std/utilities/meta/meta.unary/meta.unary.prop/is_constructible.pass.cpp +++ b/test/std/utilities/meta/meta.unary/meta.unary.prop/is_constructible.pass.cpp @@ -30,6 +30,7 @@ struct A { explicit A(int); A(int, double); + A(int, long, double); #if TEST_STD_VER >= 11 private: #endif @@ -106,6 +107,16 @@ void test_is_constructible() #endif } +template <class T, class A0, class A1, class A2> +void test_is_constructible() +{ + static_assert(( std::is_constructible<T, A0, A1, A2>::value), ""); + LIBCPP11_STATIC_ASSERT((std::__libcpp_is_constructible<T, A0, A1, A2>::type::value), ""); +#if TEST_STD_VER > 14 + static_assert(( std::is_constructible_v<T, A0, A1, A2>), ""); +#endif +} + template <class T> void test_is_not_constructible() { @@ -146,6 +157,7 @@ int main() test_is_constructible<int, const int> (); test_is_constructible<A, int> (); test_is_constructible<A, int, double> (); + test_is_constructible<A, int, long, double> (); test_is_constructible<int&, int&> (); test_is_not_constructible<A> (); |