Refer to constants in JS

Recently my Elm Chromecast app stopped working on Android. I just tracked it down to a string constant changing on the JS side. chrome.cast.AutoJoinPolicy.ORIGIN_SCOPED was “ORIGIN_SCOPED” and changed to “origin_scoped”. Of course in Elm I just have
originScoped : AutoJoinPolicy
originScoped =
I’d really like to just refer to the JS constant directly so this kind of thing can’t happen again. How would I do that?

You can pass in JS-constants to your Elm app using flags (see programWithFlags), and storing it in your model.

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This seems non-trivial. I want to pass a record that contains a bunch of constants with NAMES_LIKE_THIS, which Elm barfs on. Which may imply some JSON decoding or my munging the values before passing them in?

You can use Decoder for Flags. Just define main as Program Value model msg (where Value is Value from Json module) and use decode in init.

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