rb_define_method (c, "inspect", c_inspect, 0);
rb_define_method (c, "clear", c_clear, 0);
rb_define_method (c, "delete", c_delete, 1);
rb_define_method (c, "inspect", c_inspect, 0);
rb_define_method (c, "clear", c_clear, 0);
rb_define_method (c, "delete", c_delete, 1);