// following classes in the global namespace:
//
// 1. bidirectional_iterator
+// 2. forward_iterator
//
//===----------------------------------------------------------------------===//
: public std::iterator<std::bidirectional_iterator_tag, Ty, PtrDiffTy> {
};
+template<class Ty, class PtrDiffTy>
+struct forward_iterator
+ : public std::iterator<std::forward_iterator_tag, Ty, PtrDiffTy> {
+};
+
#else
// Just use bidirectional_iterator directly.
using std::bidirectional_iterator;
+using std::forward_iterator;
#endif
#endif