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diff --git a/odb/wrapper-traits.hxx b/odb/wrapper-traits.hxx
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+// file      : odb/wrapper-traits.hxx
+// author    : Boris Kolpackov <boris@codesynthesis.com>
+// copyright : Copyright (c) 2009-2011 Code Synthesis Tools CC
+// license   : GNU GPL v2; see accompanying LICENSE file
+
+#ifndef ODB_WRAPPER_TRAITS_HXX
+#define ODB_WRAPPER_TRAITS_HXX
+
+#include <odb/pre.hxx>
+
+#include <memory> // std::auto_ptr
+
+#include <odb/nullable.hxx>
+
+namespace odb
+{
+  template <typename T>
+  class wrapper_traits;
+
+  // Sample specialization for raw pointers. It is not enabled by default
+  // since it makes many assumptions that may not always hold true (such
+  // as that instances are allocated with new and freed with delete).
+  // This makes it too dangerous to be enable unconditionally. If you
+  // need this functionality, you can copy the below code into your
+  // application. Also consider changing it to only specialize for
+  // specific types instead of for any pointer (it will almost always
+  // do the wrong thing for char*).
+  //
+#if 0
+  template <typename T>
+  class wrapper_traits<T*>
+  {
+  public:
+    typedef T wrapped_type;
+    typedef T* wrapper_type;
+
+    static const bool null_handler = true;
+    static const bool null_default = false;
+
+    static bool
+    get_null (const wrapper_type& p)
+    {
+      return p == 0;
+    }
+
+    static void
+    set_null (wrapper_type& p)
+    {
+      delete p;
+      p = 0;
+    }
+
+    static const type&
+    get_ref (const wrapper_type& p)
+    {
+      return *p;
+    }
+
+    static type&
+    set_ref (wrapper_type& p)
+    {
+      if (p == 0)
+        p = new type;
+
+      return *p;
+    }
+  };
+#endif
+
+  // Specialization for std::auto_ptr.
+  //
+  template <typename T>
+  class wrapper_traits< std::auto_ptr<T> >
+  {
+  public:
+    typedef T wrapped_type;
+    typedef std::auto_ptr<T> wrapper_type;
+
+    static const bool null_handler = true;
+    static const bool null_default = false;
+
+    static bool
+    get_null (const wrapper_type& p)
+    {
+      return p.get () == 0;
+    }
+
+    static void
+    set_null (wrapper_type& p)
+    {
+      p.reset ();
+    }
+
+    static const wrapped_type&
+    get_ref (const wrapper_type& p)
+    {
+      return *p;
+    }
+
+    static wrapped_type&
+    set_ref (wrapper_type& p)
+    {
+      if (p.get () == 0)
+        p.reset (new wrapped_type);
+
+      return *p;
+    }
+  };
+
+  // Specialization for odb::nullable.
+  //
+  template <typename T>
+  class wrapper_traits< nullable<T> >
+  {
+  public:
+    typedef T wrapped_type;
+    typedef nullable<T> wrapper_type;
+
+    static const bool null_handler = true;
+    static const bool null_default = true;
+
+    static bool
+    get_null (const wrapper_type& n)
+    {
+      return n.null ();
+    }
+
+    static void
+    set_null (wrapper_type& n)
+    {
+      n.reset ();
+    }
+
+    static const wrapped_type&
+    get_ref (const wrapper_type& n)
+    {
+      return *n;
+    }
+
+    static wrapped_type&
+    set_ref (wrapper_type& n)
+    {
+      if (n.null ())
+        n = T ();
+
+      return *n;
+    }
+  };
+}
+
+#include <odb/post.hxx>
+
+#endif // ODB_WRAPPER_TRAITS_HXX