empty

Returns a type convertible to bool that evaluates to true if the sequence is empty, else, evaluates to false.

template <typename Sequence>
typename result_of::empty<Sequence>::type
empty(Sequence const& seq);

Parameter	Requirement	Description
`seq`	Model of Forward Sequence	The sequence we wish to investigate.

empty(seq);

Return type: Convertible to bool.

Semantics: Evaluates to true if the sequence is empty, else, evaluates to false.

#include <boost/fusion/sequence/intrinsic/empty.hpp>

vector<int, int, int> v(1, 2, 3);
assert(empty(v) == false);