//
// FROM
//

struct modevents_entry_for
{
    // This typedef is used by boost.
    typedef modevents_entry result_type;

    modevents_entry_for(const std::string& type)
        : type_(type)
    {
    }

    modevents_entry operator()(const std::string& id) const
    {
        return modevents_entry(type_, id);
    }

private:
    std::string type_;
};

boost::copy(mp_settings_.active_mods | boost::adaptors::transformed(modevents_entry_for("modification")),
    std::back_inserter(mods));

//
// TO
//

std::transform(mp_settings_.active_mods.begin(), mp_settings_.active_mods.end(), std::back_inserter(mods),
    [](const std::string& id) { return modevents_entry("modification", id); }
);