LWG Issue 2247: Implement type trait 'is_null_pointer'

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@192049 91177308-0d34-0410-b5e6-96231b3b80d8

include/type_traits

@@ -28,6 +28,7 @@ namespace std
 
     // Primary classification traits:
     template <class T> struct is_void;
+    template <class T> struct is_null_pointer;  // C++14
     template <class T> struct is_integral;
     template <class T> struct is_floating_point;
     template <class T> struct is_array;
@@ -298,6 +299,11 @@ template <>          struct ____is_nullptr_t<nullptr_t> : public true_type {};
 template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY __is_nullptr_t
     : public ____is_nullptr_t<typename remove_cv<_Tp>::type> {};
 
+#if _LIBCPP_STD_VER > 11
+template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY is_null_pointer
+    : public ____is_nullptr_t<typename remove_cv<_Tp>::type> {};
+#endif
+
 // is_integral
 
 template <class _Tp> struct __is_integral                     : public false_type {};
@@ -422,7 +428,7 @@ template <class _Tp, bool = is_class<_Tp>::value ||
                             is_union<_Tp>::value ||
                             is_void<_Tp>::value  ||
                             is_reference<_Tp>::value ||
-                            is_same<_Tp, nullptr_t>::value >
+                            __is_nullptr_t<_Tp>::value >
 struct __is_function
     : public integral_constant<bool, sizeof(__is_function_imp::__test<_Tp>(__is_function_imp::__source<_Tp>())) == 1>
     {};

test/utilities/meta/meta.unary/meta.unary.cat/array.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_array_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert( std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/class.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_class_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/enum.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_enum_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/floating_point.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_floating_point_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert( std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/function.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_function_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/integral.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_integral_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert( std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/lvalue_ref.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_lvalue_ref()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/member_function_pointer.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_member_function_pointer_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/member_object_pointer.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_member_object_pointer_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/nullptr.pass.cpp

@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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
+
+// nullptr_t
+//	is_null_pointer
+
+#include <type_traits>
+
+#if _LIBCPP_STD_VER > 11
+template <class T>
+void test_nullptr_imp()
+{
+    static_assert(!std::is_void<T>::value, "");
+    static_assert( std::is_null_pointer<T>::value, "");
+    static_assert(!std::is_integral<T>::value, "");
+    static_assert(!std::is_floating_point<T>::value, "");
+    static_assert(!std::is_array<T>::value, "");
+    static_assert(!std::is_pointer<T>::value, "");
+    static_assert(!std::is_lvalue_reference<T>::value, "");
+    static_assert(!std::is_rvalue_reference<T>::value, "");
+    static_assert(!std::is_member_object_pointer<T>::value, "");
+    static_assert(!std::is_member_function_pointer<T>::value, "");
+    static_assert(!std::is_enum<T>::value, "");
+    static_assert(!std::is_union<T>::value, "");
+    static_assert(!std::is_class<T>::value, "");
+    static_assert(!std::is_function<T>::value, "");
+}
+
+template <class T>
+void test_nullptr()
+{
+    test_nullptr_imp<T>();
+    test_nullptr_imp<const T>();
+    test_nullptr_imp<volatile T>();
+    test_nullptr_imp<const volatile T>();
+}
+
+int main()
+{
+    test_nullptr<std::nullptr_t>();
+}
+#else
+int main() {}
+#endif

test/utilities/meta/meta.unary/meta.unary.cat/pointer.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_pointer_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/rvalue_ref.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_rvalue_ref()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/union.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_union_imp()
 {
     static_assert(!std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");

test/utilities/meta/meta.unary/meta.unary.cat/void.pass.cpp

@@ -17,6 +17,9 @@ template <class T>
 void test_void_imp()
 {
     static_assert( std::is_void<T>::value, "");
+#if _LIBCPP_STD_VER > 11
+    static_assert(!std::is_null_pointer<T>::value, "");
+#endif
     static_assert(!std::is_integral<T>::value, "");
     static_assert(!std::is_floating_point<T>::value, "");
     static_assert(!std::is_array<T>::value, "");