Elm:
Getting the current date
How to:
Elm handles dates with the Time module. You’ll get the current time as a POSIX timestamp, then convert to a date.
import Browser
import Task
import Time
type Msg = GetCurrentTime Time.Posix
update : Msg -> Model -> (Model, Cmd Msg)
update msg model =
case msg of
GetCurrentTime posixTime ->
let
-- Convert POSIX time to a date record
date = Time.toDate posixTime
in
-- Update your model accordingly here
({ model | date = date }, Cmd.none)
-- To initiate getting the current time
getCurrentTime : Cmd Msg
getCurrentTime =
Task.perform GetCurrentTime Time.now
-- Example output:
-- date { year = 2023, month = Mar, day = 26 }Deep Dive
In older web languages, grabbing the date is one-liner code. Elm is different. It makes side-effects like getting the current time explicit through the Elm Architecture. This encourages purity and maintainability of code.
Alternatives include using third-party packages or handling dates in your server code and passing them to Elm through flags or ports.
Implementation-wise, Elm’s Time.now gets the time as a POSIX timestamp (milliseconds since Unix epoch). This is timezone-agnostic, and you can format it as needed using functions from the Time module.