2020-01-18 15:24:37 +00:00
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#+title: Abstractions; Haskell vs Clojure
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#+subtitle: How are both Haskell and Clojure good to capture some abstractions
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#+date: [2020-01-18 Sat]
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#+created: [2020-01-18 Sat]
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#+author: Yann Esposito
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#+EMAIL: yann@esposito.host
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2021-04-27 13:21:06 +00:00
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#+keywords: Haskell Clojure functional-programming
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2020-01-18 15:24:37 +00:00
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#+DESCRIPTION: Simulate some abstractions in Clojure vs Haskell
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#+OPTIONS: auto-id:t toc:t
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#+STARTUP: overview
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#+begin_notes
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This is a short essay to try to find if Haskell is as limited in its
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abstractions power as I experienced many times when learning it.
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Now I've got a lot more experience in Haskell and in Clojure.
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I would like to see if I'll be able to manage to put some abstractions in
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Haskell and in Clojure.
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#+end_notes
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* Abstractions
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:PROPERTIES:
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:CUSTOM_ID: abstractions
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:END:
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The notion of abstraction is generally not pretty well defined.
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For example, not using pointer can be considered an abstraction.
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Garbage collection is an abstraction.
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Procedures are an abstraction.
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ORM are an abstraction.
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Monads are an abstraction.
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Objects and Classes are an abstraction.
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I would be surprised is not anyone has made a kind of hierarchy to organize
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different abstractions as they seems to me of different nature.
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In this post I will only focus on those few abstractions:
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- Object Oriented Programming (Objects and Classes, inheritence, etc...)
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- Frameworks for managing the lifecycle and dependencies of software
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components with have runtime state (in Clojure: Component or Trapperkeeper)
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- ORM/Store abstractions
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* Object Oriented
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:PROPERTIES:
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:CUSTOM_ID: object-oriented
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:END:
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So in Clojure, this is quite straightforward if you consider you are
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authorized to use the underlying language (java).
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** Haskell
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:PROPERTIES:
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:CUSTOM_ID: haskell
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:END:
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Notion of Object, something that contain an inner state + some methods.
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Notion of Class, a boilerplate for creating new Objects.
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#+begin_src haskell
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newtype MethodName = MethodName Text
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data Object s m = Object { state :: s
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, methods :: forall a. MethodName -> s -> a }
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#+end_src
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hmmm.... At the very begining of trying to write it down, it already suck...
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