Implement data and size functions

test/data_test.cpp

@@ -0,0 +1,68 @@
+/*
+Copyright 2023 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#include <boost/config.hpp>
+#if !defined(BOOST_NO_CXX11_CONSTEXPR) && !defined(BOOST_NO_CXX11_DECLTYPE)
+#include <boost/core/data.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+class range {
+public:
+    int* data() {
+        return &v_[0];
+    }
+
+    const int* data() const {
+        return &v_[0];
+    }
+
+    std::size_t size() const {
+        return 4;
+    }
+
+private:
+    int v_[4];
+};
+
+void test_range()
+{
+    range c;
+    BOOST_TEST_EQ(boost::data(c), c.data());
+}
+
+void test_const_range()
+{
+    const range c = range();
+    BOOST_TEST_EQ(boost::data(c), c.data());
+}
+
+void test_array()
+{
+    int a[4];
+    BOOST_TEST_EQ(boost::data(a), a);
+}
+
+void test_initializer_list()
+{
+    std::initializer_list<int> l{1, 2, 3, 4};
+    BOOST_TEST_EQ(boost::data(l), l.begin());
+}
+
+int main()
+{
+    test_range();
+    test_const_range();
+    test_array();
+    test_initializer_list();
+    return boost::report_errors();
+}
+#else
+int main()
+{
+    return 0;
+}
+#endif