std::literals::string_literals::operator""s
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
#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"
See also
constructs a basic_string (public member function) |
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