weekday_indexed() = default; | (1) | (since C++20) |

constexpr weekday_indexed( const std::chrono::weekday& wd, unsigned index ) noexcept; | (2) | (since C++20) |

Constructs a `weekday_indexed`

.

1) Default constructor leaves both the

`std::chrono::weekday`

and the index value uninitialized.
2) Constructs a

`weekday_indexed`

storing the weekday `wd`

and the index `index`

. The values held are unspecified if `!wd.ok() || index > 7`

.A more convenient way to construct a `weekday_indexed`

is with `weekday`

's `operator[]`

, i.e., `wd[index]`

.

#include <chrono> #include <iostream> using namespace std::chrono; int main() { constexpr auto third_friday = weekday_indexed(Friday, 3); // uses constructor (2) static_assert(third_friday == Friday[3]); weekday_indexed wdi = Tuesday[2]; // represents the 2nd Tuesday std::cout << year_month_day{ wdi / October / 2019y } << '\n'; }

Possible output:

2019-10-08

convenience syntax for constructing a `weekday_indexed` or `weekday_last` from this `weekday` (public member function of `std::chrono::weekday` ) |

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