boost/preprocessor/facilities/is_empty.hpp
# /* ************************************************************************** # * * # * (C) Copyright Paul Mensonides 2003. # * Distributed under the Boost Software License, Version 1.0. (See # * accompanying file LICENSE_1_0.txt or copy at # * http://www.boost.org/LICENSE_1_0.txt) # * * # ************************************************************************** */ # # /* See http://www.boost.org for most recent version. */ # # ifndef BOOST_PREPROCESSOR_FACILITIES_IS_EMPTY_HPP # define BOOST_PREPROCESSOR_FACILITIES_IS_EMPTY_HPP # # include <boost/preprocessor/config/config.hpp> # include <boost/preprocessor/cat.hpp> # include <boost/preprocessor/tuple/elem.hpp> # include <boost/preprocessor/facilities/empty.hpp> # include <boost/preprocessor/detail/split.hpp> # # /* BOOST_PP_IS_EMPTY */ # # if ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MSVC() && ~BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MWCC() # define BOOST_PP_IS_EMPTY(x) BOOST_PP_IS_EMPTY_I(x BOOST_PP_IS_EMPTY_HELPER) # define BOOST_PP_IS_EMPTY_I(contents) BOOST_PP_TUPLE_ELEM(2, 1, (BOOST_PP_IS_EMPTY_DEF_ ## contents())) # define BOOST_PP_IS_EMPTY_DEF_BOOST_PP_IS_EMPTY_HELPER 1, 1 BOOST_PP_EMPTY # define BOOST_PP_IS_EMPTY_HELPER() , 0 # else # if BOOST_PP_CONFIG_FLAGS() & BOOST_PP_CONFIG_MSVC() # define BOOST_PP_IS_EMPTY(x) BOOST_PP_IS_EMPTY_I(BOOST_PP_IS_EMPTY_HELPER x ()) # define BOOST_PP_IS_EMPTY_I(test) BOOST_PP_IS_EMPTY_II(BOOST_PP_SPLIT(0, BOOST_PP_CAT(BOOST_PP_IS_EMPTY_DEF_, test))) # define BOOST_PP_IS_EMPTY_II(id) id # else # define BOOST_PP_IS_EMPTY(x) BOOST_PP_IS_EMPTY_I((BOOST_PP_IS_EMPTY_HELPER x ())) # define BOOST_PP_IS_EMPTY_I(par) BOOST_PP_IS_EMPTY_II ## par # define BOOST_PP_IS_EMPTY_II(test) BOOST_PP_SPLIT(0, BOOST_PP_CAT(BOOST_PP_IS_EMPTY_DEF_, test)) # endif # define BOOST_PP_IS_EMPTY_HELPER() 1 # define BOOST_PP_IS_EMPTY_DEF_1 1, BOOST_PP_NIL # define BOOST_PP_IS_EMPTY_DEF_BOOST_PP_IS_EMPTY_HELPER 0, BOOST_PP_NIL # endif # # endif