anchor.diff:  import           Control.Monad            (join)
   import           Control.Monad.Logger (runNoLoggingT)
   import           Data.Maybe               (isJust)
  -import           Data.Text                (Text)
  +import           Data.Text                (Text, unpack)
   import qualified Data.Text.Lazy.Encoding
   import           Data.Typeable            (Typeable)
   import           Database.Persist.Sqlite
  
positive.code:     addUnverified email verkey =
          runDB $ insert $ User email Nothing (Just verkey) False
  
      sendVerifyEmail email _ verurl =
          liftIO $ renderSendMail (emptyMail $ Address Nothing "noreply")
              { mailTo = [Address Nothing email]
              , mailHeaders =
  
negative.code: Let's have a look at a site that provides email authentication, storing
  passwords in a Persistent SQLite database.
  
  NOTE: Even if you don't have an email server, for debugging purposes the
  verification link is printed in the console.
  
  [source, haskell]
  ----
  {-# LANGUAGE DeriveDataTypeable         #-}
  