1.5 KiB
1.5 KiB
Rust-chrono
Date and time handling for Rust.
// find out if the doomsday rule is correct!
use chrono::{Weekday, NaiveDate, naive};
use std::iter::range_inclusive;
for y in range_inclusive(naive::date::MIN.year(), naive::date::MAX.year()) {
// even months
let d4 = NaiveDate::from_ymd(y, 4, 4);
let d6 = NaiveDate::from_ymd(y, 6, 6);
let d8 = NaiveDate::from_ymd(y, 8, 8);
let d10 = NaiveDate::from_ymd(y, 10, 10);
let d12 = NaiveDate::from_ymd(y, 12, 12);
// nine to five, seven-eleven
let d59 = NaiveDate::from_ymd(y, 5, 9);
let d95 = NaiveDate::from_ymd(y, 9, 5);
let d711 = NaiveDate::from_ymd(y, 7, 11);
let d117 = NaiveDate::from_ymd(y, 11, 7);
// "March 0"
let d30 = NaiveDate::from_ymd(y, 3, 1).pred();
let weekday = d30.weekday();
let other_dates = [d4, d6, d8, d10, d12, d59, d95, d711, d117];
assert!(other_dates.iter().all(|d| d.weekday() == weekday));
}
Design Goals
- 1-to-1 correspondence with ISO 8601.
- Timezone-aware by default.
- Space efficient.
- Moderate lookup table size, should not exceed a few KBs.
- Avoid divisions as much as possible.