Question

The boost function make_function_output_iterator converts a function that would be appropriate for std::for_each into an iterator appropriate for std::copy. Is there a boost function that does the reverse. That is, takes an iterator appropriate for std::copy and converts it to a function appropriate for std::for_each.

So if I have an output iterator output_iter. I need

for_each(v1.begin(), v1.end(), make_output_iterator_function(output_iter));

To do the same thing as

copy(v1.begin(), v1.end(), output_iter);

Answer 1

Maybe std::insert_iterator or std::transform are what you are looking for?

You can bind std::insert_iterator::operator=, which does an insert on every invocation, with some boost::bind sorcery:

#include <boost/bind.hpp>
#include <vector>
#include <iterator>
#include <algorithm>

    typedef std::vector<int> Container;
    typedef std::insert_iterator< Container > InsertIt;

int main(){
    Container v1, v2;
    InsertIt insert_it (v2,v2.end());
    std::for_each(v1.begin(), v1.end(),
            boost::bind(static_cast<InsertIt& (InsertIt::*)(typename Container::const_reference)>(&InsertIt::operator=), insert_it, _1));
}