BOOST_VMD_IS_EMPTY_LIST_D — Tests whether a sequence is an empty Boost PP list. Re-entrant version.
// In header: <boost/vmd/is_empty_list.hpp> BOOST_VMD_IS_EMPTY_LIST_D(d, sequence)
An empty Boost PP list consists of the single identifier 'BOOST_PP_NIL'. This identifier also serves as a list terminator for a non-empty list.
d = The next available BOOST_PP_WHILE iteration sequence = a preprocessor parameter
returns = 1 if the sequence is an empty Boost PP list 0 if it is not.
The macro will generate a preprocessing error if the input as an empty list marker, instead of being an identifier, is a preprocessor token which VMD cannot parse, as in the example '&BOOST_PP_NIL'.