Functor / IO Gripes

strtest.hs

import Data.Char

str2Upper :: String -> String
str2Upper name = map toUpper name

main = do 
  -- LHS line becomes string; RHS is IO String
  line <- fmap reverse getLine
  
  -- Since line is now String, we can assign using let to line2,
  -- meanwhile applying the __pure__ function str2Upper
  let line2 = str2Upper line
  putStrLn $ "HI THERE, " ++ line2