I'm guessing that since Haskell's ghci is not a full-fledged REPL, you can't really use it for defining functions in orgmode source blocks, i.e.,
#+begin_src haskell doubleMe x = x + x #+end_src
isn't allowed in the ghci. But then
#+begin_src haskell let doubleMe x = x + x #+end_src
#+begin_src haskell let doubleSmallNumber4 x = if x > 0 then x else x*2 #+end_src
complains about parsing the
else. I'm assuming Haskell and orgmode simply don't play well together -- at least when it comes to using orgmode source blocks . . . or am I missing something?