3_3_3_myasks_mytell.hs

import Control.Monad.Trans.Reader
import Control.Monad.Trans.Writer
import Control.Monad.Trans (lift)
import Data.Char (toUpper)

type MyRW = ReaderT [String] (Writer String)

logFirstAndRetSecond :: MyRW String
logFirstAndRetSecond = do
  el1 <- myAsks head
  el2 <- myAsks (map toUpper . head . tail)
  myTell el1
  return el2

runMyRW rw e = runWriter (runReaderT rw e)

myAsks :: ([String] -> a) -> MyRW a
myAsks = asks

myTell :: String -> MyRW ()
myTell = lift . tell

strings = ["abc", "defg", "hij"]
ex = runMyRW logFirstAndRetSecond strings