Data.Thyme.Calendar.MonthDay

Calendar month. January = 1

Calendar day-of-month, starting from 1.

A strict pair of a Month and a DayOfMonth.

Predicated on whether or not it's a leap year, convert between an ordinal DayOfYear and the corresponding Month and DayOfMonth.

> 60 ^. monthDay (isLeapYear 2015)
MonthDay {mdMonth = 3, mdDay = 1}

> 60 ^. monthDay (isLeapYear 2016)
MonthDay {mdMonth = 2, mdDay = 29}

> monthDay (isLeapYear 2016) # MonthDay 2 29
60

> monthDay (isLeapYear 2015) # MonthDay 2 28
59

Note that monthDay is an improper Iso, as the following example shows. To handle this case correctly, use monthDayValid.

> monthDay (isLeapYear 2015) # MonthDay 2 29
59

Predicated on whether or not it's a leap year, convert a MonthDay to an ordinal DayOfYear.

> monthDayValid (isLeapYear 2016) (MonthDay 2 29)
Just 60

> monthDayValid (isLeapYear 2015) (MonthDay 2 29)
Nothing

Predicated on whether or not the year is a leap year, return the number of Days in the given Month.

> monthLength (isLeapYear 2015) 2
  28

> monthLength (isLeapYear 2016) 2
  29

Predicated on whether or not it is a leap year, convert an ordinal DayOfYear to its corresponding Month and DayOfMonth.

dayOfYearToMonthAndDay leap (view (monthDay leap) -> MonthDay m d) = (m, d)

Predicated on whether or not it is a leap year, convert a Month and DayOfMonth to its corresponding ordinal DayOfYear. Does not validate the input.

monthAndDayToDayOfYear leap m d = monthDay leap # MonthDay m d

Predicated on whether or not it is a leap year, convert a Month and DayOfMonth to its corresponding ordinal DayOfYear. Returns Nothing for invalid input.

monthAndDayToDayOfYearValid leap m d = monthDayValid leap (MonthDay m d)