#include <bits/stl_function.h>
#include <cmath>
-#include <string>
#include <typeinfo>
-#include <ext/type_traits.h>
#include <tr1/tuple>
#include <tr1/type_traits>
+#include <bits/stringfwd.h>
#include <tr1/functional_hash.h>
#if defined(_GLIBCXX_INCLUDE_AS_TR1)