Illegal type: ‘"Hello"’ Perhaps you intended to use DataKinds

[theobat]

hey, I'm struggling with the very basic examples:

{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE TypeApplications #-}
{-# LANGUAGE TypeOperators #-}

import Data.Text (Text)
import Data.Monoid ((<>))

import GraphQL
import GraphQL.API
import GraphQL.Resolver (Handler)

type Hello = Object "Hello" '[]
  '[ Argument "who" Text :> Field "greeting" Text ]

Yields:

error:
    Illegal type: ‘"Hello"’ Perhaps you intended to use DataKinds
   |
16 | type Hello = Object "Hello" '[]
   |                     ^^^^^^^

And many others like that... Any idea of what I could be doing wrong ?

[theobat]

adding the suggested {-# LANGUAGE DataKinds #-} seems to fix the problem, perhaps this should be added in the readme snippet...

[ronanyeah]

I just got burned by this.

@theobat If you reopen this issue I am willing to make a PR to the README.