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

 

C++

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Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

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Filesystem library (C++17)

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Technical Specifications

 

Strings library

Null-terminated strings

Byte strings

Multibyte strings

Wide strings

Classes

basic_string

basic_string_view (C++17)

char_traits

 

std::basic_string

Member functions basic_string::basic_string basic_string::operator= basic_string::assign basic_string::get_allocator Element access basic_string::at basic_string::operator[] basic_string::front (C++11) basic_string::back (C++11) basic_string::data basic_string::c_str basic_string::operator basic_string_view (C++17) Iterators basic_string::beginbasic_string::cbegin (C++11) basic_string::endbasic_string::cend (C++11) basic_string::rbeginbasic_string::crbegin (C++11) basic_string::rendbasic_string::crend (C++11) Capacity basic_string::empty basic_string::sizebasic_string::length basic_string::max_size basic_string::reserve basic_string::capacity basic_string::shrink_to_fit (C++11)

Operations basic_string::clear basic_string::insert basic_string::erase basic_string::push_back basic_string::pop_back (C++11) basic_string::append basic_string::operator+= basic_string::compare basic_string::starts_with (C++20) basic_string::ends_with (C++20) basic_string::replace basic_string::substr basic_string::copy basic_string::resize basic_string::swap Search basic_string::find basic_string::rfind basic_string::find_first_of basic_string::find_first_not_of basic_string::find_last_of basic_string::find_last_not_of Constants basic_string::npos

Non-member functions operator+ swap(std::basic_string) operator""s (C++14) erase(std::basic_string)erase_if(std::basic_string) (C++20)(C++20) I/O operator<<operator>> getline Comparison operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20) Numeric conversion (C++11) stoistolstoll stoulstoull stofstodstold to_string to_wstring Helper classes hash<std::string>hash<std::wstring>hash<std::u32string>hash<std::u16string>hash<std::u8string> (C++11)(C++11)(C++11)(C++11)(C++20) hash<std::pmr::string>hash<std::pmr::wstring>hash<std::pmr::u32string>hash<std::pmr::u16string>hash<std::pmr::u8string> (C++20)(C++20)(C++20)(C++20)(C++20) Deduction guides(C++17)

 

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

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"

See also

(constructor)

constructs a basic_string (public member function)