std::chrono::weekday_indexed:: index

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C++
Utilities library
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chrono I/O
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C-style date and time
std::chrono::weekday_indexed
constexpr unsigned index ( ) const noexcept ;
(since C++20)

Accesses the index stored in * this .

Return value

The index stored in * this .

Example

Run this code 
#include <chrono>
#include <iostream>
 
int main()
{
    std::cout << std::boolalpha;
 
    std::chrono::weekday_indexed wdi {std::chrono::Tuesday[2]}; // 2nd Tuesday of a month
    std::cout << (std::chrono::year_month_day{wdi/10/2019} == 
                  std::chrono::year_month_day{std::chrono::October/8/2019}) << ' ';
 
    wdi = {wdi.weekday()[wdi.index() + 2]}; // 2nd Tuesday => 4th Tuesday
    std::cout << (std::chrono::year_month_day{wdi/10/2019} == 
                  std::chrono::year_month_day{std::chrono::October/22/2019}) << '\n';
}

Output: 

true true
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