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The Dark Side of JavaScript

Sponsored · Ship Features Fearlessly Turn features on and off without deploys. Used by thousands of Ruby developers. →
Avatar for Lucas Santos Lucas Santos
May 17, 2021
Technology
110
0

The Dark Side of JavaScript

Avatar for Lucas Santos

Lucas Santos

May 17, 2021

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Transcript

  1. Javascript as you never saw before

  2. cloud advocate_ who am I_ [email protected] {twitter, facebook, linkedin…}.lsantos.dev

  3. The magic JS

  4. Removing Callbacks

  5. The Dark Side of Javascript JS

  6. Symbols

  7. None
  8. None
  9. None

  10. BUT BE AWARE_

  11. Small usage example

  12. Other usage example in Node.js source code bit.ly/nodejs-symbol Check it

    out!

  13. Async Iterators_

  14. None
  15. None
  16. None
  17. None
  18. None
  19. None
  20. None

  21. Promise.finally

  22. None

  23. Promise.allSettled

  24. None
  25. None

  26. Ranges

  27. None
  28. None
  29. None

  30. Readonly properties_

  31. Object.defineProperty

  32. None

  33. Object.defineProperties

  34. ‘age’ hasn’t been shown because it’s not enumerable

  35. Private class fields_

  36. None
  37. None

  38. Dynamic function creation_

  39. None
  40. None

  41. in operator_

  42. None
  43. None

  44. Dynamic instances by reflection_

  45. None
  46. None
  47. None

  48. Bitwise Operators_

  49. AND

  50. None

  51. What!?

  52. A B C D Result X 0 1 0 1

    5 Y 0 0 0 1 1 Z 0 0 0 1 1

  53. String as binary data

  54. OR

  55. None

  56. A B C D Result X 0 1 0 1

    5 Y 0 0 0 1 1 Z 0 1 0 1 5

  57. XOR

  58. None

  59. A B C D Result X 0 1 0 1

    5 Y 0 0 0 1 1 Z 0 1 0 0 4

  60. Cryptography

  61. None

  62. NOT

  63. None

  64. A B C D Resultado X 0 1 0 1

    5 Z 1 0 1 0 10

  65. Existence condition

  66. None

  67. SHIFT

  68. None

  69. Multiply and divide

  70. None

  71. refs_ - imasters.com.br/desenvolvimento/o-lado-escuro-javascript - medium.com/trainingcenter/entendendo-promises-de-uma-vez-por-todas-3 2442ec725c2 - imasters.com.br/desenvolvimento/campos-publicos-e-privados-em-classes-j avascript-o-que-vem-por-ai-no-esnext -

    imasters.com.br/javascript/futuro-das-promises-no-javascript - medium.com/trainingcenter/iterators-em-javascript-880adef14495 - medium.com/trainingcenter/reflection-em-javascript-73fc0e702e2 - developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objec ts/Reflect - slides.lsantos.dev/desmistificando-heranca-e-prototipos-no-javascript - dev.to/khaosdoctor/entendendo-async-iterators-1opo

  72. thank you_ info.lsantos.dev