std::literals::string_literals::operator""s (3) - Linux Manuals

std::literals::string_literals::operator""s: std::literals::string_literals::operator""s

NAME

std::literals::string_literals::operator""s - std::literals::string_literals::operator""s

Synopsis

Defined in header <string>
string operator "" s(const char *str, std::size_t len); (1) (since C++14)
u8string operator "" s(const char8_t *str, std::size_t len); (2) (since C++20)
u16string operator "" s(const char16_t *str, std::size_t len); (3) (since C++14)
u32string operator "" s(const char32_t *str, std::size_t len); (4) (since C++14)
wstring operator "" s(const wchar_t *str, std::size_t len); (5) (since C++14)

Forms a string literal of the desired type.
1) returns std::string{str, len}
2) returns std::u8string{str, len}
3) returns std::u16string{str, len}
4) returns std::u32string{str, len}
5) returns std::wstring{str, len}

Parameters

str - pointer to the beginning of the raw character array literal
len - length of the raw character array literal

Return value

The string literal.

Notes

These operators are declared in the namespace std::literals::string_literals, where both literals and string_literals are inline namespaces. Access to these operators can be gained with using namespace std::literals, using namespace std::string_literals, and using namespace std::literals::string_literals.
std::chrono::duration also defines operator""s, to represent literal seconds, but it is an arithmetic literal: 10.0s and 10s are ten seconds, but "10"s is a string.

Example

// Run this code

  #include <string>
  #include <iostream>

  int main()
  {
      using namespace std::string_literals;

      std::string s1 = "abc\0\0def";
      std::string s2 = "abc\0\0def"s;
      std::cout << "s1: " << s1.size() << " \"" << s1 << "\"\n";
      std::cout << "s2: " << s2.size() << " \"" << s2 << "\"\n";
  }

Possible output:

  s1: 3 "abc"
  s2: 8 "abc^@^@def"