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std::basic_string<CharT,Traits,Allocator>::empty

bool empty() const;
 (until C++11) 
bool empty() const noexcept;
 (since C++11)
(until C++20) 
[[nodiscard]] bool empty() const noexcept;
 (since C++20)

Checks if the string has no characters, i.e. whether begin() == end().

Parameters

(none).

Return value

true if the string is empty, false otherwise.

Complexity

Constant.

Example

#include <iostream>
#include <string>
 
int main()
{
    std::string s;
    std::boolalpha(std::cout);
    std::cout << "s.empty():" << s.empty() << "\t s:'" << s << "'\n";
 
    s = "Exemplar";
    std::cout << "s.empty():" << s.empty() << "\t s:'" << s << "'\n";
 
    s = "";
    std::cout << "s.empty():" << s.empty() << "\t s:'" << s << "'\n";
}

Output:

s.empty():true         s:''
s.empty():false         s:'Exemplar'
s.empty():true         s:''

See also

returns the number of characters
(public member function)

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