(C++17) | ||||
| Sequence | ||||
(C++11) | ||||
(C++26) | ||||
(C++26) | ||||
(C++11) | ||||
| Associative | ||||
| Unordered associative | ||||
(C++11) | ||||
(C++11) | ||||
(C++11) | ||||
(C++11) | ||||
| Adaptors | ||||
(C++23) | ||||
(C++23) | ||||
(C++23) | ||||
(C++23) | ||||
| Views | ||||
(C++20) | ||||
(C++23) | ||||
| Tables | ||||
| Iterator invalidation | ||||
| Member function table | ||||
| Non-member function table |
| Member functions | ||||
| Element access | ||||
(C++26) | ||||
| Iterators | ||||
(C++23) | ||||
(C++23) | ||||
(C++23) | ||||
(C++23) | ||||
| Observers | ||||
span::empty | ||||
| Subviews | ||||
| Non-member functions | ||||
| Non-member constant | ||||
| Deduction guides |
constexprbool empty()constnoexcept; | (since C++20) | |
Checks if the span is empty. Equivalent toreturn size()==0;.
true if the span is empty;false otherwise.
#include <iomanip>#include <iostream>#include <span> int main(){std::span<constchar> span{"ABCDEF"}; while(!span.empty()){std::cout<<std::quoted(span.data())<<'\n'; span= span.last(span.size()-1);}}
Output:
"ABCDEF""BCDEF""CDEF""DEF""EF""F"""
(C++20) | returns the number of elements in the sequence (public member function)[edit] |
