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Elm a possible future for web frontend
The document discusses Elm, a functional programming language designed for web frontends, emphasizing its features like static typing, immutability, and a message-passing architecture. It compares Elm's approach to JavaScript's handling of effects and asynchronous operations, illustrating with examples such as a counter app and a dice roller app. The text poses the question of whether Elm could be a viable future alternative to modern JavaScript frameworks, highlighting the ease of understanding and testing in Elm.
Elm a possible future for web frontend
- 1. ELM A possible futurefor web frontend
- 2. Agenda What is Elm?Elm features Elm ecosystem Elm architecture Why a possible future?
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- 4. Functional language ML stylelanguage Inspired by Haskell
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- 6. Statically typed ∎ Primitive types ∎Basic data structures ∎ Union types
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- 12. Purely functional ∎ Functions dependonly on passed arguments ∎ No side effects
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- 14. Effects in JS ∎Synchronous ∎ Asynchronous via callback ∎ Asynchronous via promise
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- 22. Effects in Elm ∎Synchronous via Messages ∎ Asynchronous via Tasks
- 23. Elm Tasks ∎ Modulefor async actions that might fail ∎ Tasks can be easily chained together ∎ Lazy: nothing will happen until something run them.
- 24. Interop with JS: Ports ∎Only way you have to receive or send informations from JS. ∎ It works like a pub-sub mechanism.
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- 26. Basic Pattern: Counter App ∎Model ∎ Messages ∎ Update ∎ View
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- 29. Counter: User Flow User clickson the “+” button Increment action is fired Update function gets called View gets updated
- 30. Commands and Subscriptions ∎ Commands:Tasks that Elm runs for you in the background ∎ Subscriptions: subscribe to data you care about
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- 32. Dice Roller: User Flow Userclicks on the “Roll” button Roll action is fired Update function returns command Elm executes the task “New Number” action is fired Update function gets called View gets updated
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- 40. I don’t needElm! Functional programming Modern JS is inspired by FP Components React Effect as data Flux / Redux Type checking Flow.js / Typescript Immutability ImmutableJS / Ramda / Lodash Modules Webpack / Babel
- 41. ∎ Syntax ∎ Types ∎Immutability Learning curve ∎ Compiling ∎ Maybe and explicit error handling
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- 43. Hard to start newprojects
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- 47. Everything that issyntactically legal, that the compiler will accept, will eventually wind up in your code base. John Carmack
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- 55. Will Elm be thefuture?