Unix epoch

Keep track of each part of time. Use toParts to create parts from posix time.

import Iso8601
import Time


epoch
    |> toParts utc
    |> withYear 2022
    |> withMonth Time.Jul
    |> withDay 22
    |> withHour 14
    |> withMinute 32
    |> withSecond 17
    |> withMillis 678
    |> fromParts utc
    |> Ok
--> Iso8601.toTime "2022-07-22T14:32:17.678Z"

Convert posix time to Parts.

Convert Parts back to posix time.

import Iso8601
import Time




-- Extract several eras from America/New_York for testing
-- summer : 2022-03-13T02:00:00-05:00 -> 2022-03-13T03:00:00-04:00
-- winter : 2022-11-06T02:00:00-04:00 -> 2022-11-06T01:00:00-05:00
newYork : Zone
newYork =
    customZone ""
        [ { start = 27976740, offset = -240 } -- 2023-03-12T03:00:00-04:00
        , { start = 27795240, offset = -300 } -- 2022-11-06T01:00:00-05:00
        , { start = 27452580, offset = -240 } -- 2022-03-13T03:00:00-04:00
        , { start = 27271080, offset = -300 } -- 2021-11-07T01:00:00-05:00
        ]
        -300


-- Extract several eras from Europe/Paris for testing
-- summer : 2022-03-27T02:00:00+01:00 -> 2022-03-27T03:00:00+02:00
-- winter : 2022-10-30T03:00:00+02:00 -> 2022-10-30T02:00:00+01:00
paris : Time2.Zone
paris =
    customZone ""
        [ { start = 27996540, offset = 120 } -- 2023-03-26T03:00:00+02:00
        , { start = 27784860, offset = 60 } -- 2022-10-30T02:00:00+01:00
        , { start = 27472380, offset = 120 } -- 2022-03-27T03:00:00+02:00
        , { start = 27260700, offset = 60 } -- 2021-10-31T02:00:00+01:00
        ]
        60


epoch
    |> toParts newYork
    |> withYear 2022
    |> withMonth Time.Mar
    |> withDay 13
    |> withHour 1
    |> withMinute 59
    |> withSecond 59
    |> fromParts newYork
    |> Ok
--> Iso8601.toTime "2022-03-13T01:59:59-05:00"


epoch
    |> toParts newYork
    |> withYear 2022
    |> withMonth Time.Mar
    |> withDay 13
    |> withHour 2
    |> fromParts newYork
    |> Ok
--> Iso8601.toTime "2022-03-13T03:00:00-04:00"


epoch
    |> toParts newYork
    |> withYear 2022
    |> withMonth Time.Mar
    |> withDay 13
    |> withHour 3
    |> fromParts newYork
    |> Ok
--> Iso8601.toTime "2022-03-13T03:00:00-04:00"


-- `fromParts` gives the second 01:59:59
epoch
    |> toParts newYork
    |> withYear 2022
    |> withMonth Time.Nov
    |> withDay 6
    |> withHour 1
    |> withMinute 59
    |> withSecond 59
    |> fromParts newYork
    |> Ok
--> Iso8601.toTime "2022-11-06T01:59:59-05:00"


-- `fromParts` gives the second 2022-11-06T02:00:00
epoch
    |> toParts newYork
    |> withYear 2022
    |> withMonth Time.Nov
    |> withDay 6
    |> withHour 2
    |> fromParts newYork
    |> Ok
--> Iso8601.toTime "2022-11-06T02:00:00-05:00"


epoch
    |> toParts paris
    |> withYear 2022
    |> withMonth Time.Mar
    |> withDay 27
    |> withHour 1
    |> withMinute 59
    |> withSecond 59
    |> fromParts paris
    |> Ok
--> Iso8601.toTime "2022-03-27T01:59:59+01:00"


epoch
    |> toParts paris
    |> withYear 2022
    |> withMonth Time.Mar
    |> withDay 27
    |> withHour 2
    |> fromParts paris
    |> Ok
--> Iso8601.toTime "2022-03-27T03:00:00+02:00"


epoch
    |> toParts paris
    |> withYear 2022
    |> withMonth Time.Mar
    |> withDay 27
    |> withHour 3
    |> fromParts paris
    |> Ok
--> Iso8601.toTime "2022-03-27T03:00:00+02:00"


-- `fromParts` gives the second 2022-10-30T02:59:59
epoch
    |> toParts paris
    |> withYear 2022
    |> withMonth Time.Oct
    |> withDay 30
    |> withHour 2
    |> withMinute 59
    |> withSecond 59
    |> fromParts paris
    |> Ok
--> Iso8601.toTime "2022-10-30T02:59:59+01:00"


-- `fromParts` gives the second 2022-10-30T03:00:00
epoch
    |> toParts paris
    |> withYear 2022
    |> withMonth Time.Oct
    |> withDay 30
    |> withHour 3
    |> fromParts paris
    |> Ok
--> Iso8601.toTime "2022-10-30T03:00:00+01:00"

Set year of Parts.

Set month of Parts.

Set day of Parts.

Set hour of Parts.

Set minute of Parts.

Set second of Parts.

Set millis of Parts.

A zone is a list of eras sorted by descending order of the starting point of each era.

Note that we don't expose the variants because we don't want to bump major version of the package too often. Use customZone if we want to create a zone manually. Or create a decoder to decode the value encoded by encodeZone if we want to get the raw data, we'll try to keep encodeZone backward compatible.

Get the name of a zone.

getZoneName utc
--> "Etc/UTC"

Create a zone with name, eras and offsetOfEarliestEra.

utc

Encode Zone so we can send it through wire.

import Json.Decode


zone : Zone
zone =
    customZone "Zone/Name"
        [ { start = 20, offset = 60 }
        , { start = 10, offset = -120 }
        ]
        30


zone
    |> encodeZone
    |> Json.Decode.decodeValue decoderOfZone
--> Ok zone

Decode Json.Encode.Value back to Zone.

This function converts Time2.Zone to Time.Zone.

import Time

start : Int
start =
    61


zone : Time.Zone
zone =
    customZone "" [ { start = start, offset = 120 } ] 0
        |> toElmTimeZone


Time.millisToPosix (start * 60 * 1000)
    |> Time.toHour zone
--> 3 -- This will be 1 once https://github.com/elm/time/issues/7 is fixed, we then need to fix our implementation

Deprecated, please use toElmTimeZone as that name is less misleading.