std::chrono::weekday::c_encoding, std::chrono::weekday::iso_encoding

constexpr unsigned c_encoding() const noexcept;	(1)	(since C++20)
constexpr unsigned iso_encoding() const noexcept;	(2)	(since C++20)

1) Returns the weekday value stored in *this.

2) Returns the weekday value stored in *this, except that Sunday (stored as 0) is interpreted as 7 according to ISO 8601.

Return value

1) The weekday value stored in *this.

2) c_encoding() == 0u ? 7u : c_encoding()

Example

#include <chrono>
#include <iostream>
 
int main()
{
    std::cout << "i: C: ISO: Weekday:\n";
 
    for (unsigned i{0}; i != 8; ++i)
    {
        const std::chrono::weekday w{i};
        std::cout << i << "  "
                  << w.c_encoding() << "  "
                  << w.iso_encoding() << "    "
                  << w << '\n';
    }
}

Output:

i: C: ISO: Weekday:
0  0  7    Sun
1  1  1    Mon
2  2  2    Tue
3  3  3    Wed
4  4  4    Thu
5  5  5    Fri
6  6  6    Sat
7  0  7    Sun

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