std::span<T,Extent>:: empty
From cppreference.net
C++
Containers library
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(C++11)
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(C++26)
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(C++20)
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std::span
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span::empty
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| Deduction guides |
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constexpr
bool
empty
(
)
const
noexcept
;
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(depuis C++20) | |
Vérifie si l'étendue est vide. Équivalent à return size ( ) == 0 ; .
Valeur de retour
true si la plage est vide ; false sinon.
Exemple
Exécuter ce code
#include <iomanip> #include <iostream> #include <span> int main() { std::span<const char> span{"ABCDEF"}; while (!span.empty()) { std::cout << std::quoted(span.data()) << '\n'; span = span.last(span.size() - 1); } }
Sortie :
"ABCDEF" "BCDEF" "CDEF" "DEF" "EF" "F" ""
Voir aussi
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(C++20)
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retourne le nombre d'éléments dans la séquence
(fonction membre publique) |