[libcxx] r201703 - Implement LWG Issue: 2280. begin/end for arrays should be constexpr and noexcept, plus a drive-by fix for cbegin/cend suggested by Peter Sommerlad.

[Marshall Clow]

Author: marshall
Date: Wed Feb 19 11:53:30 2014
New Revision: 201703

URL: http://llvm.org/viewvc/llvm-project?rev=201703&view=rev
Log:
Implement LWG Issue: 2280. begin/end for arrays should be constexpr and noexcept, plus a drive-by fix for cbegin/cend suggested by Peter Sommerlad.

Modified:
    libcxx/trunk/include/iterator
    libcxx/trunk/test/iterators/iterator.range/begin-end.pass.cpp

Modified: libcxx/trunk/include/iterator
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/iterator?rev=201703&r1=201702&r2=201703&view=diff
==============================================================================
--- libcxx/trunk/include/iterator (original)
+++ libcxx/trunk/include/iterator Wed Feb 19 11:53:30 2014
@@ -1386,7 +1386,7 @@ operator+(typename __wrap_iter<_Iter>::d
 }
 
 template <class _Tp, size_t _Np>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
 _Tp*
 begin(_Tp (&__array)[_Np])
 {
@@ -1394,7 +1394,7 @@ begin(_Tp (&__array)[_Np])
 }
 
 template <class _Tp, size_t _Np>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
 _Tp*
 end(_Tp (&__array)[_Np])
 {
@@ -1466,17 +1466,17 @@ reverse_iterator<const _Ep*> rend(initia
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
 auto cbegin(const _Cp& __c) -> decltype(begin(__c))
 {
-    return _VSTD::begin(__c);
+    return begin(__c);
 }
 
 template <class _Cp>
-inline _LIBCPP_INLINE_VISIBILITY
+inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX11
 auto cend(const _Cp& __c) -> decltype(end(__c))
 {
-    return _VSTD::end(__c);
+    return end(__c);
 }
 
 template <class _Cp>

Modified: libcxx/trunk/test/iterators/iterator.range/begin-end.pass.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/iterators/iterator.range/begin-end.pass.cpp?rev=201703&r1=201702&r2=201703&view=diff
==============================================================================
--- libcxx/trunk/test/iterators/iterator.range/begin-end.pass.cpp (original)
+++ libcxx/trunk/test/iterators/iterator.range/begin-end.pass.cpp Wed Feb 19 11:53:30 2014
@@ -52,7 +52,7 @@ void test_const_container( const std::in
     assert ( std::end(c)     == c.end());
 #if _LIBCPP_STD_VER > 11
 //  initializer_list doesn't have cbegin/cend/rbegin/rend
-//	but std::cbegin(),etc work (b/c they're general fn templates)
+//  but std::cbegin(),etc work (b/c they're general fn templates)
 //     assert ( std::cbegin(c)  == c.cbegin());
 //     assert ( std::cbegin(c)  != c.cend());
 //     assert ( std::cend(c)    == c.cend());
@@ -104,6 +104,20 @@ void test_container( std::initializer_li
 #endif
     }
 
+template<typename T, size_t Sz>
+void test_const_array( const T (&array)[Sz] ) {
+    assert ( std::begin(array)  == array );
+    assert (*std::begin(array)  ==  array[0] );
+    assert ( std::begin(array)  != std::end(array));
+    assert ( std::end(array)    == array + Sz);
+#if _LIBCPP_STD_VER > 11
+    assert ( std::cbegin(array) == array );
+    assert (*std::cbegin(array) == array[0] );
+    assert ( std::cbegin(array) != std::cend(array));
+    assert ( std::cend(array)   == array + Sz);
+#endif
+    }
+
 int main(){
     std::vector<int> v; v.push_back(1);
     std::list<int> l;   l.push_back(2);
@@ -119,6 +133,14 @@ int main(){
     test_const_container ( l, 2 );
     test_const_container ( a, 3 );
     test_const_container ( il, 4 );
+    
+    static constexpr int arrA [] { 1, 2, 3 };
+    test_const_array ( arrA );
+#if _LIBCPP_STD_VER > 11
+    constexpr const int *b = std::cbegin(arrA);
+    constexpr const int *e = std::cend(arrA);
+    static_assert(e - b == 3, "");
+#endif
 }
 
 #else