Functional JavaScript

Introduction about what's and how to program functional javascript

Transcript

1. FUNCTIONAL PROGRAMMING IN JAVASCRIPT
2. MEDSON OLIVEIRA Full Stack Developer at ASTROCODERS github.com/medson10 @o_medson @MedsonOliveira medson.oliveira.jr@gmail.com
3. What's functional programming?
7. What makes a language have the possibility of being functional? • Immutability • First class functions • Recursion • Expression oriented programming
8. Immutability? a value can be defined just one time
9. First class functions • Lambda expressions • Lexical closures • High order functions
10. Why Recursion? "Is not just much more elegant, but also the only way to iterate without invoking side-effects"
11. Expression oriented programming? Everything returns a value
12. How JavaScript can be functional?
13. JavaScript is not a pure functional language!!!!!1 • Doesn't have immutability • JavaScript is object based, everything is an object • Type system supeeeerrrrr dynamic
14. So what's the point?
15. Functional is not just a kind of programming language but also a way to program and organize your code
17. So can I program in a functional way in all the others languages?
19. What's needed for code in a functional way? • First class functions • Immutability • Recursion
20. And how we can start it on JavaScript?
24. What would be Functional JavaScript?
25. CONST now, CONST tomorrow, CONST forever
26. Pure functions
27. Side Effects
28. Pipe instead of Chain
29. But why? Let's think in a case a little more complex
30. And about performance? What is the pipe behind?
31. Let's curry some functions
32. And how ramda helps us with all this? https://ramdajs.com/docs/#
33. HERE I AM!!!!!!!!
34. But why not code in a functional language and compile it to JavaScript?
36. References https://github.com/stoeffel/awesome-fp-js https://lukajcb.github.io/blog/functional/2016/07/31/what-makes-a-language-functio nal.html https://hackernoon.com/two-years-of-functional-programming-in-javascript-lessons-l earned-1851667c726 https://github.com/hemanth/functional-programming-jargon https://hackernoon.com/currying-in-js-d9ddc64f162e