Implement LWG #2212: std::is_final. This requires compiler support, w…

…hich modern versions of clang provide. Also mark LWG #2230 as complete - no code changes needed.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@202934 91177308-0d34-0410-b5e6-96231b3b80d8

include/type_traits

@@ -91,6 +91,7 @@ namespace std
     template <class T> struct is_empty;
     template <class T> struct is_polymorphic;
     template <class T> struct is_abstract;
+    template <class T> struct is_final; // C++14
 
     template <class T, class... Args> struct is_constructible;
     template <class T>                struct is_default_constructible;
@@ -759,6 +760,13 @@ template <class _Tp> struct __libcpp_abstract<_Tp, false> : public false_type {}
 
 template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY is_abstract : public __libcpp_abstract<_Tp> {};
 
+// is_final
+
+#if __has_feature(is_final)
+template <class _Tp> struct _LIBCPP_TYPE_VIS_ONLY 
+is_final : public integral_constant<bool, __is_final(_Tp)> {};
+#endif
+
 // is_base_of
 
 #ifdef _LIBCPP_HAS_IS_BASE_OF

test/utilities/meta/meta.unary/meta.unary.prop/is_final.pass.cpp

@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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
+
+// is_final
+
+#include <type_traits>
+
+#if __cplusplus >= 201103L
+
+struct P final { };
+union U1 { };
+union U2 final { };
+
+template <class T>
+void test_is_final()
+{
+    static_assert( std::is_final<T>::value, "");
+    static_assert( std::is_final<const T>::value, "");
+    static_assert( std::is_final<volatile T>::value, "");
+    static_assert( std::is_final<const volatile T>::value, "");
+}
+
+template <class T>
+void test_is_not_final()
+{
+    static_assert(!std::is_final<T>::value, "");
+    static_assert(!std::is_final<const T>::value, "");
+    static_assert(!std::is_final<volatile T>::value, "");
+    static_assert(!std::is_final<const volatile T>::value, "");
+}
+
+int main ()
+{
+    test_is_not_final<int>();
+    test_is_not_final<int*>();
+    test_is_final    <P>(); 
+    test_is_not_final<P*>();    
+    test_is_not_final<U1>();
+    test_is_not_final<U1*>();
+    test_is_final    <U2>();    
+    test_is_not_final<U2*>();   
+}
+#else
+int main () {}
+#endif

www/cxx1y_status.html

@@ -230,7 +230,7 @@ <h3>Library Working group Issues Status</h3>
 
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#1450">1450</a></td><td>Contradiction in regex_constants</td><td>Issaquah</td><td>Complete</td></tr>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2003">2003</a></td><td>String exception inconsistency in erase.</td><td>Issaquah</td><td>Complete</td></tr>
-	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2112">2112</a></td><td>User-defined classes that cannot be derived from</td><td>Issaquah</td><td></td></tr>
+	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2112">2112</a></td><td>User-defined classes that cannot be derived from</td><td>Issaquah</td><td>Complete</td></tr>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2132">2132</a></td><td>std::function ambiguity</td><td>Issaquah</td><td></td></tr>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2182">2182</a></td><td>Container::[const_]reference types are misleadingly specified</td><td>Issaquah</td><td>Complete</td></tr>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2188">2188</a></td><td>Reverse iterator does not fully support targets that overload operator&</td><td>Issaquah</td><td>Complete</td></tr>
@@ -255,7 +255,7 @@ <h3>Library Working group Issues Status</h3>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2323">2323</a></td><td>vector::resize(n, t)'s specification should be simplified</td><td>Issaquah</td><td>Complete</td></tr>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2324">2324</a></td><td>Insert iterator constructors should use addressof()</td><td>Issaquah</td><td>Complete</td></tr>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2329">2329</a></td><td>regex_match()/regex_search() with match_results should forbid temporary strings</td><td>Issaquah</td><td>Complete</td></tr>
-	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2330">2330</a></td><td>regex("meow", regex::icase) is technically forbidden but should be permitted</td><td>Issaquah</td><td></td></tr>
+	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2330">2330</a></td><td>regex("meow", regex::icase) is technically forbidden but should be permitted</td><td>Issaquah</td><td>Complete</td></tr>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2332">2332</a></td><td>regex_iterator/regex_token_iterator should forbid temporary regexes</td><td>Issaquah</td><td>Complete</td></tr>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2339">2339</a></td><td>Wording issue in nth_element</td><td>Issaquah</td><td>Complete</td></tr>
 	<tr><td><a href="http://www.open-std.org/jtc1/sc22/wg21/docs/lwg-defects.html#2341">2341</a></td><td>Inconsistency between basic_ostream::seekp(pos) and basic_ostream::seekp(off, dir)</td><td>Issaquah</td><td>Complete</td></tr>