Construct ZonedTime from proleptic Gregorian calendar day in UTC. Invalid values will return Nothing.

import Time


sample : Maybe ZonedTime
sample =
    fromGregorianUtc
        { year = 2000
        , month = Time.Jun
        , day = 10
        }
        |> Maybe.map (addHours 22)
        |> Maybe.map (addMinutes 33)
        |> Maybe.map (addSeconds 44)
        |> Maybe.map (addMillis 55)


Maybe.map toZone sample
--> Just Time.utc


Maybe.map getYear sample
--> Just 2000


Maybe.map getMonth sample
--> Just Time.Jun


Maybe.map getDay sample
--> Just 10


Maybe.map getHour sample
--> Just 22


Maybe.map getMinute sample
--> Just 33


Maybe.map getSecond sample
--> Just 44


Maybe.map getMillis sample
--> Just 55


fromGregorianUtc
    { year = 1999
    , month = Time.Feb
    , day = 29
    }
--> Nothing

Overwrite time zone. Make sure it will not change internal POSIX time value.

import Time


-- 1970-01-04T13:54:12.123Z
original : ZonedTime
original = fromPosix Time.utc (Time.millisToPosix 309252123)


fooZone : Time.Zone
fooZone = Time.customZone (9 * 60) []


sample1 : ZonedTime
sample1 =
    original
        |> overwriteZone fooZone


sample2 : ZonedTime
sample2 =
    original
        |> addHours -9
        |> overwriteZone fooZone


toZone sample1
--> fooZone


toZone sample2
--> fooZone


getHour sample1
--> 22


getHour sample2
--> 13

Modify internal POSIX time value.

Set time to midnight of the day in the time zone.

import Time


-- 1970-01-04T13:54:12.123Z
original : ZonedTime
original = fromPosix Time.utc (Time.millisToPosix 309252123)


midnight : ZonedTime
midnight =
    setToMidnight original


getYear original
--> 1970


getYear midnight
--> 1970


getMonth original
--> Time.Jan


getMonth midnight
--> Time.Jan


getDay original
--> 4


getDay midnight
--> 4


getHour midnight
--> 0


getMinute midnight
--> 0


getSecond midnight
--> 0


getMillis midnight
--> 0

Check if the year of given number is a leap year.

Return the number of days in the year specified as an argument.

Return the number of days in the month specified by the given year and month arguments.