$(singletons [d|
       data EventScans
        = PassThrough
        | SuiteProgress

       -- cn :: EventScans -> [Char]
       cn PassThrough = "all-events"
       cn SuiteProgress = "suite-progress"
    |])

* Expected kind `[Char]', but `"all-events"' has kind `Symbol'
* In the type `"all-events"'
  In the type family declaration for `Cn' (haskell-stack-ghc)