[Boost-users] [mpl] no result_type defined

Hi! I want to create a container of pointers to objects in a range (first,last(. I tried to use mpl, but have been without success. I understand, that the lambda "&_1" cannot specify its concrete return type, so I added ret<T>(...). But the resulting lambda is rejected by the make_transform_iterator function. I'm using boost 1.33.0 on gcc 4.0.2 //****** CODE BEGIN ****** #include <vector> #include <iterator> #include #include template<typename Iterator> void foo(Iterator first, Iterator last) { using boost::make_transform_iterator; using namespace boost::lambda; typedef typename std::iterator_traits<Iterator>::pointer Pointer; std::vector<Pointer> objectPointers( make_transform_iterator(first, ret<Pointer>(&_1)), make_transform_iterator(last, ret<Pointer>(&_1)) ); // ... } int main() { std::vector<int> v; //instantiate template: foo(v.begin(), v.end()); } //***** CODE END ****** // ** ERROR on GCC 4.0.2: ** /mnt/daten/develop/boost/boost/iterator/transform_iterator.hpp:43: Fehler: kein Typ namens »result_type« in »class boost::lambda::lambda_functor, boost::tuples::tupleboost::lambda::addressof_action, boost::tuples::tuple

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The error says it cannot find the type "result_type" in "class ....". What is wrong here? Frank