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# gregorianStartDate

The start date of the Gregorian calendar for the receiver.

```
var gregorianStartDate: Date? { get set }
```

## Discussion

This is used to specify the start date for the Gregorian calendar switch from the Julian calendar. Different locales switched at different times. Normally you should just accept the locale’s default date for the switch.

See [`NSCalendar`](/documentation/Foundation/NSCalendar) for more information.

---

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