15 lines
593 B
V
15 lines
593 B
V
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module time
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// days_from_civil - return the number of days since the
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// Unix epoch 1970-01-01. A detailed description of the algorithm here
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// is in: http://howardhinnant.github.io/date_algorithms.html
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// Note that it will return negative values for days before 1970-01-01.
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pub fn days_from_civil(oy int, m int, d int) int {
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y := if m <= 2 { oy - 1 } else { oy }
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era := y / 400
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yoe := y - era * 400 // [0, 399]
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doy := (153 * (m + (if m > 2 { -3 } else { 9 })) + 2) / 5 + d - 1 // [0, 365]
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doe := yoe * 365 + yoe / 4 - yoe / 100 + doy // [0, 146096]
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return era * 146097 + doe - 719468
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}
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