#+TITLE: Haskell Design Pattern in Clojure
#+SUBTITLE: Some classical haskell tricks equivalent in Clojure
#+AUTHOR: Yann Esposito
#+EMAIL: yann@esposito.host
#+DATE: [2019-11-07 Thu]
#+KEYWORDS: programming
#+DESCRIPTION: LISP to simulate Haskell
#+OPTIONS: auto-id:t

#+begin_notes
TL;DR: Some clever Haskell trick can in fact be simulated quite efficiently
with Clojure.
#+end_notes

* Monads
:PROPERTIES:
:CUSTOM_ID: monads
:END:

#+begin_src haskell
  fullName :: Maybe Text -> Maybe Text -> Maybe Text
  fullName firstName lastName = do
      x <- firstName
      y <- lastName
      result <- return (x <> y)

  ask :: IO (Maybe Text)
  ask = do
    l <- readLine
    return $ if null l then Nothing else Just l

  askName <- fullName <$> ask "What is your first name?"
                      <*> ask "What is your last name?"
#+end_src