stupidlensing.hs

{-# LANGUAGE Rank2Types #-}
import Control.Lens hiding (element)
import Data.Text as T (splitOn
                     , concat
                     , Text
                     , pack
                     , toTitle
                     , toLower)

twiceLens :: String -> Iso' Text (String, Text)
twiceLens x = iso (\t -> (x, (head (splitOn (pack x) t))))
                  (\(c, t) -> T.concat [t, (pack c), t])

capitalizeLens :: Iso' Text Text
capitalizeLens = iso toLower toTitle

restaurize :: String -> String -> String -> Text
restaurize x s l = over (salsaLens s l)
                        (const $ pack x)
                        (pack (l++s++l))

    where salsaLens s l = capitalizeLens
                        . (twiceLens s)
                        . traverse
                        . (twiceLens l)
                        . traverse

main = do
  print $ restaurize "sa" " " "l"