Fail Instance without TypeString/TypeConcat

Main.purs

module Main where

import Prelude
import Control.Monad.Eff.Console (log)

class Serialize a where
  serialize :: a -> String

instance cannotSerializeFunctions 
    :: Fail ("Cannot serialize functions.") 
    => Serialize (a -> b) where
  serialize _ = "unreachable"

main = do
  log (serialize ((+) 1))