Member fun value() that throws on uninitialized

test/optional_test_value_access.cpp

@@ -0,0 +1,107 @@
+// Copyright (C) 2014 Andrzej Krzemienski.
+//
+// Use, modification, and distribution is subject to the Boost Software
+// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//
+// See http://www.boost.org/lib/optional for documentation.
+//
+// You are welcome to contact the author at:
+//  akrzemi1@gmail.com
+//
+// Revisions:
+//
+#include<iostream>
+#include<stdexcept>
+#include<string>
+
+#define BOOST_ENABLE_ASSERT_HANDLER
+
+#include "boost/bind/apply.hpp" // Included just to test proper interaction with boost::apply<> as reported by Daniel Wallin
+#include "boost/mpl/bool.hpp"
+#include "boost/mpl/bool_fwd.hpp"  // For mpl::true_ and mpl::false_
+
+#include "boost/optional/optional.hpp"
+
+#ifdef __BORLANDC__
+#pragma hdrstop
+#endif
+
+#include "boost/none.hpp"
+
+#include "boost/test/minimal.hpp"
+
+#include "optional_test_common.cpp"
+
+struct IntWrapper
+{
+  int _i;
+  IntWrapper(int i) : _i(i) {}
+  bool operator==(IntWrapper const& rhs) const { return _i == rhs._i; }
+};
+
+template <typename T>
+void test_function_value_for()
+{
+  optional<T> o0;
+  optional<T> o1(1);
+  const optional<T> oC(2);
+  
+  try
+  {
+    T& v = o1.value();
+    BOOST_CHECK(v == 1);
+  }
+  catch(...)
+  {
+    BOOST_CHECK(false);
+  }
+  
+  try
+  {
+    T const& v = oC.value();
+    BOOST_CHECK(v == 2);
+  }
+  catch(...)
+  {
+    BOOST_CHECK(false);
+  }
+  
+  try
+  {
+    T& v = o0.value();
+    BOOST_CHECK(false);
+    unused_variable(v);
+  }
+  catch(boost::bad_optional_access const&)
+  {
+  }
+  catch(...)
+  {
+    BOOST_CHECK(false);
+  }
+}
+
+void test_function_value()
+{
+    test_function_value_for<int>();
+    test_function_value_for<float>();
+    test_function_value_for<IntWrapper>();
+}
+
+int test_main( int, char* [] )
+{
+  try
+  {
+    test_function_value();
+
+  }
+  catch ( ... )
+  {
+    BOOST_ERROR("Unexpected Exception caught!");
+  }
+
+  return 0;
+}
+
+