...one of the most highly
regarded and expertly designed C++ library projects in the
world. — Herb Sutter and Andrei
BOOST_VMD_IS_EMPTY_LIST — Tests whether a sequence is an empty Boost PP list.
// In header: <boost/vmd/is_empty_list.hpp> BOOST_VMD_IS_EMPTY_LIST(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.
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'.