35 lines
843 B
Org Mode
35 lines
843 B
Org Mode
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#+TITLE: Haskell Design Pattern in Clojure
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#+SUBTITLE: Some classical haskell tricks equivalent in Clojure
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#+AUTHOR: Yann Esposito
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#+EMAIL: yann@esposito.host
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#+DATE: [2019-11-07 Thu]
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#+KEYWORDS: programming
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#+DESCRIPTION: LISP to simulate Haskell
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#+OPTIONS: auto-id:t
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#+begin_notes
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TL;DR: Some clever Haskell trick can in fact be simulated quite efficiently
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with Clojure.
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#+end_notes
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* Monads
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:PROPERTIES:
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:CUSTOM_ID: monads
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:END:
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#+begin_src haskell
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fullName :: Maybe Text -> Maybe Text -> Maybe Text
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fullName firstName lastName = do
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x <- firstName
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y <- lastName
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result <- return (x <> y)
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ask :: IO (Maybe Text)
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ask = do
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l <- readLine
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return $ if null l then Nothing else Just l
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askName <- fullName <$> ask "What is your first name?"
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<*> ask "What is your last name?"
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#+end_src
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