Add array_get_test_cx.cpp

include/boost/array.hpp

@@ -458,13 +458,13 @@ namespace boost {
     }
 
    template <size_t Idx, typename T, size_t N>
-   T &get(boost::array<T,N> &arr) BOOST_NOEXCEPT {
+   BOOST_CXX14_CONSTEXPR T &get(boost::array<T,N> &arr) BOOST_NOEXCEPT {
        BOOST_STATIC_ASSERT_MSG ( Idx < N, "boost::get<>(boost::array &) index out of range" );
        return arr[Idx];
        }
 
    template <size_t Idx, typename T, size_t N>
-   const T &get(const boost::array<T,N> &arr) BOOST_NOEXCEPT {
+   BOOST_CONSTEXPR const T &get(const boost::array<T,N> &arr) BOOST_NOEXCEPT {
        BOOST_STATIC_ASSERT_MSG ( Idx < N, "boost::get<>(const boost::array &) index out of range" );
        return arr[Idx];
        }

test/Jamfile.v2

@@ -55,6 +55,7 @@ compile array_data_test_cx.cpp ;
 compile array_iterator_test_cx.cpp ;
 compile array_size_test_cx.cpp ;
 compile array_access_test_cx.cpp ;
+compile array_get_test_cx.cpp ;
 
 # C++14 constexpr
 

test/array_get_test_cx.cpp

@@ -0,0 +1,42 @@
+// Copyright 2025 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt)
+
+#include <boost/array.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+#include <boost/config/workaround.hpp>
+#include <cstddef>
+
+#if defined(BOOST_NO_CXX11_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE("Test skipped because BOOST_NO_CXX11_CONSTEXPR is defined")
+
+#elif BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+
+BOOST_PRAGMA_MESSAGE("Test skipped because BOOST_MSVC < 1910")
+
+#elif BOOST_WORKAROUND(BOOST_GCC, < 50000)
+
+BOOST_PRAGMA_MESSAGE("Test skipped because BOOST_GCC < 50000")
+
+#else
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+
+template<class T> void test()
+{
+    constexpr boost::array<T, 4> a = {{ 1, 2, 3, 4 }};
+
+    STATIC_ASSERT( boost::get<0>( a ) == 1 );
+    STATIC_ASSERT( boost::get<1>( a ) == 2 );
+    STATIC_ASSERT( boost::get<2>( a ) == 3 );
+    STATIC_ASSERT( boost::get<3>( a ) == 4 );
+}
+
+int main()
+{
+    test<int>();
+}
+
+#endif