...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
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 |
---|---|---|
|
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> #include <boost/fusion/include/empty.hpp>
vector
<int, int, int> v(1, 2, 3);
assert(empty(v) == false);