Many initial tutorials of Elm show us how we can display an Integer as String using the util function called toString.

Example

module Main exposing (main)

import Html


add a b =
    a + b


result =
    add 1 2 |> add 3


main =
    Html.text (toString result)

But with the new version, precisely v0.19 this shows an error.

To solve this error, simply replace toString with Debug.toString.

module Main exposing (main)

import Html


add a b =
    a + b


result =
    add 1 2 |> add 3


main =
    Html.text (Debug.toString result)

See the upgrade instructions for more information.