[Boost-users] transform_iterator and lambda functors

Hello, I am trying to use transform_iterator with a lambda functor, but the compiler complains that the lambda functor does not contain a type called 'result_type', which the transform_iterator requires. I would have expected lambda functors to have this type. Any ideas on why it doesn't? Here is the code line causing the problem: return make_transform_iterator(attributes.begin(), bind(&pair::second, _1)); where attributes is of type map. Here is the error message: /usr/local/include/boost-1_32/boost/iterator/transform_iterator.hpp:43: no type named `result_type' in `class boost::lambda::lambda_functor

, boost::tuples::tuple::*, const boost::lambda::lambda_functor >, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type> > >'

Thanks, Rodrigo