content: {-# LANGUAGE CPP                       #-}
  {-# LANGUAGE DataKinds                 #-}
  {-# LANGUAGE DuplicateRecordFields     #-}
  {-# LANGUAGE ExistentialQuantification #-}
  {-# LANGUAGE FlexibleContexts          #-}
  {-# LANGUAGE FlexibleInstances         #-}
  {-# LANGUAGE GADTs                     #-}
  {-# LANGUAGE KindSignatures            #-}
  {-# LANGUAGE MultiParamTypeClasses     #-}
  {-# LANGUAGE PartialTypeSignatures     #-}
  {-# LANGUAGE RankNTypes                #-}
  {-# LANGUAGE StandaloneDeriving        #-}
  {-# LANGUAGE TypeApplications          #-}
  {-# LANGUAGE TypeFamilies              #-}
  {-# LANGUAGE TypeOperators             #-}
  {-# LANGUAGE TypeSynonymInstances      #-}
  {-# LANGUAGE UndecidableInstances      #-}
  
  {-# OPTIONS_GHC -Wall #-}
  
  {-# OPTIONS_GHC -Werror                        #-}
  {-# OPTIONS_GHC -Wincomplete-record-updates    #-}
  {-# OPTIONS_GHC -Wno-incomplete-record-updates #-}
  {-# OPTIONS_GHC -Wno-partial-type-signatures   #-}
  {-# OPTIONS_GHC -Wno-type-defaults             #-}
  {-# OPTIONS_GHC -Wno-unused-top-binds          #-}
  
  #if __GLASGOW_HASKELL__ >= 902
  {-# OPTIONS_GHC -Wno-ambiguous-fields #-}
  #endif
  