enum base gregorian month
JANUARY(31, 31)
FEBRUARY(28, 29)
MARCH(31, 31)
APRIL(30, 30)
MAY(31, 31)
JUNE(30, 30)
JULY(31, 31)
AUGUST(31, 31)
SEPTEMBER(30, 30)
OCTOBER(31, 31)
NOVEMBER(30, 30)
DECEMBER(31, 31)
nonnegative the min days
nonnegative the max days
Index base 1 (January is 1, February is 2, and so on.)
override nonnegative index base 1
Minimum number of days in the month (31 in January, 28 in February, etc.)
override nonnegative min days
Maximum number of days in the month (31 in January, 29 in February, etc.) The only difference between min_days and max_days os for February.
override nonnegative max days