ghc-dup: f65ecfa9ddc914e8ffdff6660ae8b005f24dc718

     1: import GHC.Dup
     2: import System.Environment
     3: 
     4: main = do
     5:     a <- getArgs
     6:     let l = [length a .. 10000]
     7:     case dup l of Box x -> print (length x)
     8:     print (last l)