Elm:
Parsing HTML

How to:

Elm doesn’t have a built-in library for parsing HTML directly akin to libraries in JavaScript or Python due to its emphasis on type safety and avoiding runtime errors. However, you can use Http requests to fetch content and then use regular expressions or server-side processing to extract needed information. For more complex HTML parsing, a common approach involves using a dedicated backend service to parse the HTML and return the data in a format Elm can work with directly, like JSON.

Here’s an example of fetching HTML content (assuming the server response is in a clean format or a specific tag content):

import Browser
import Html exposing (Html, text)
import Http

type alias Model =
    { content : String }

initialModel : Model
initialModel =
    { content = "" }

type Msg
    = Fetch
    | ReceiveContent String

update : Msg -> Model -> (Model, Cmd Msg)
update msg model =
    case msg of
        Fetch ->
            ( model
            , Http.get
                { url = "https://example.com"
                , expect = Http.expectString ReceiveContent
                }
            )

        ReceiveContent content ->
            ( { model | content = content }
            , Cmd.none
            )

view : Model -> Html Msg
view model =
    text model.content

-- Assume the main function and subscriptions definitions follow Elm's standard application structure.

For processing the response to actually parse specific elements or data, you might consider sending the HTML content to a server endpoint you control, where you can use libraries available in languages like JavaScript (Cheerio, Jsdom) or Python (BeautifulSoup, lxml) for parsing, and then return structured data (like JSON) back to your Elm application.

Remember, directly parsing HTML in client-side Elm code is not the typical pattern due to language constraints and the philosophy of encouraging a clear separation between content fetching and content processing. The Elm architecture leans towards processing data in a safer, more predictable format like JSON.