Days

The Modified Julian Day is a standard count of days, with zero being the day 1858-11-17.

Constructors

ModifiedJulianDay
Fields toModifiedJulianDay :: Integer

Instances

Enum Day
Eq Day
Data Day
Ord Day
Read Day
Show Day
Ix Day
Typeable Day
ParseTime Day
FormatTime Day

addDays :: Integer -> Day -> Day Source

diffDays :: Day -> Day -> Integer Source

Gregorian calendar

toGregorian :: Day -> (Integer, Int, Int)Source

convert to proleptic Gregorian calendar. First element of result is year, second month number (1-12), third day (1-31).

fromGregorian :: Integer -> Int -> Int -> Day Source

convert from proleptic Gregorian calendar. First argument is year, second month number (1-12), third day (1-31). Invalid values will be clipped to the correct range, month first, then day.

fromGregorianValid :: Integer -> Int -> Int -> Maybe Day Source

convert from proleptic Gregorian calendar. First argument is year, second month number (1-12), third day (1-31). Invalid values will return Nothing

showGregorian :: Day -> String Source

show in ISO 8601 format (yyyy-mm-dd)

gregorianMonthLength :: Integer -> Int -> Int Source

The number of days in a given month according to the proleptic Gregorian calendar. First argument is year, second is month.

addGregorianMonthsClip :: Integer -> Day -> Day Source

Add months, with days past the last day of the month clipped to the last day. For instance, 2005-01-30 + 1 month = 2005-02-28.

addGregorianMonthsRollOver :: Integer -> Day -> Day Source

Add months, with days past the last day of the month rolling over to the next month. For instance, 2005-01-30 + 1 month = 2005-03-02.

addGregorianYearsClip :: Integer -> Day -> Day Source

Add years, matching month and day, with Feb 29th clipped to Feb 28th if necessary. For instance, 2004-02-29 + 2 years = 2006-02-28.

addGregorianYearsRollOver :: Integer -> Day -> Day Source

Add years, matching month and day, with Feb 29th rolled over to Mar 1st if necessary. For instance, 2004-02-29 + 2 years = 2006-03-01.

isLeapYear :: Integer -> Bool Source

Is this year a leap year according to the proleptic Gregorian calendar?