std::basic_string_view<CharT,Traits>::empty

Since C++17

Checks if the view has no characters, i.e. whether size() == 0.

# Declarations

constexpr bool empty() const noexcept;

(since C++17)

# Return value

true if the view is empty, false otherwise.

# Example

#include <iostream>
#include <string_view>
 
// Print a string surrounded by single quotes, its
// length and whether it is considered empty.
void check_string(std::string_view ref)
{
    std::cout << std::boolalpha
              << "'" << ref << "' has " << ref.size()
              << " character(s); emptiness: " << ref.empty() << '\n';
}
 
int main(int argc, char **argv)
{
    // An empty string
    check_string("");
 
    // Almost always not empty: argv[0]
    if (argc > 0)
        check_string(argv[0]);
}

# See also