If the array to be converted is empty, as represented by '( 0, () )', the resulting list is empty, as represented by 'BOOST_PP_NIL'.
#include <boost/preprocessor/array/to_list.hpp>
BOOST_PP_ARRAY_TO_LIST((3, (x, y, z)))
// expands to (x, (y, (z, BOOST_PP_NIL)))
Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at www.boost.org/LICENSE_1_0.txt)