 element is a list, else a tuple type is returned if the element is a tuple, else the actual type is returned for non-tuple data.</p>
<p>If BOOST_VMD_RETURN_TYPE_TUPLE is specified a tuple type is returned for all tuple-like data, else the actual type is returned for non-tuple data.</p>
<p>If BOOST_VMD_RETURN_NO_TYPE is specified it is ignored since the macro always returns the type of the sequence.</p>
<p>If more than one return type optional parameter is specified the last one specified determines the ret