In my Flutter application I have multiple different languages, I use JSON (arb files) for localization (translation).

I have a widget with a variable number of cards and to fill the textual content of the cards I (ab)use the ICU Select option, as suggested here, like this:

"card": "{choice, select, 0{Text 0.} 1{Text 1.} 2{Text 2.} 3{Text 3.} other{}}",
"@card": {
  "placeholders": {
    "choice": {}
  }
},

I need to know the length of the Select, to know how many cards to create (4 in the example code).
And I need to read it from the Select because it varies depending on the fields and potentially even depending on the language.

I could put the total in other but the text files will be filled by other people, so I don’t want there to be conflicts and I want to make sure I always read the actual content.

How can I read the Select length?
Or is there a smarter way to handle messages in this case?

Thanks in advance!