+extern const rb_data_type_t notmuch_rb_database_type;
+extern const rb_data_type_t notmuch_rb_directory_type;
+extern const rb_data_type_t notmuch_rb_filenames_type;
+extern const rb_data_type_t notmuch_rb_query_type;
+extern const rb_data_type_t notmuch_rb_threads_type;
+extern const rb_data_type_t notmuch_rb_thread_type;
+extern const rb_data_type_t notmuch_rb_messages_type;
+extern const rb_data_type_t notmuch_rb_message_type;
+extern const rb_data_type_t notmuch_rb_tags_type;
+
+#define Data_Get_Notmuch_Object(obj, type, ptr) \