auto_cast.hpp

template <typename Source>
struct auto_cast_helper {
    Source const& value;

    explicit auto_cast_helper(Source const& value) : value(value) { }

    template <typename Target>
    operator Target() const {
        return static_cast<Target>(value);
    }
};

template <typename Source>
auto_cast_helper<Source> auto_cast(Source const& value) {
    return auto_cast_helper<Source>(value);
}