Why can't I store boost::function in std::list?

error: expected `;' before 'it'"

#include <boost/function.hpp>
#include <list>

template< class T >
void example() {
    std::list< boost::function<T ()> >::iterator it;
}

template< class T >
void example() {
    typename std::list< boost::function<T ()> >::iterator it;
}

std::list< boost::function<T ()> >::iterator * it;