kleisli arrows

[Francesco Lazzarino]

i'm reading http://www.cse.chalmers.se/~rjmh/afp-arrows.pdf

count w = Kleisli readFile >>>

               arr words >>> arr (filter (==w)) >>> arr length >>>

               Kleisli print

I get that Kleisli (f::a -> m b) makes an Monad m => Kleisli m a b which is an instance of Arrow, and that a b c >>> a c d means a b d.

just making sure i'm getting all the parts:

• arr words without a context has no concrete type beyond Arrow a => a [String] (is concrete type the correct term?)
  
• given the context of Kleisli readFile >> arr words, the type system knows that arr words :: Kleisli IO String [String]
  

are both points true and complete?

thanks guys,

-franco