^date::create(number of days since EPOCH)
Constructor with only one parameter is designed for specifying relative date values. Having object of class date, one can make up a new object of the same type, whose value will be shifted with respect to the initial.
Example $now[^date:now[]]
$date_after_week[^date::create($now+7)]
The example creates a date to come a week after the current.
Parameter of the constructor does not have to be an integer number.