gistfile1.txt

    template <typename Object, typename Source, typename Iteratee>
    inline Object assignWith(Object& object, const Source & source, Iteratee iteratee ) {
        using source_info = _::Private::key_value_info<Source>;
        using object_info = _::Private::key_value_info<Object>;

        _underline_static_assert_is_iteratee_invokable("_::assignWith: ", (_::Private::is_invokable5<Iteratee,
                                                        typename object_info::value_type,
                                                        typename source_info::value_type,
                                                        typename source_info::key_type,
                                                        Object, Source>::value));

        forIn(source, [&](const typename source_info::value_type& value,
                         const typename source_info::key_type& key) {
            auto ret = Private::invoke(iteratee,
                            Private::read(object, key),
                            value,
                            key,
                            object,
                            source);
            Private::write(object, key, ret);
        });

        return object;
    }