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Event Loop

Avatar for overthemike overthemike
October 20, 2015
Technology
89
1

Event Loop

Just a quick glance at how the event loop works in JavaScript.

Avatar for overthemike

overthemike

October 20, 2015

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Transcript

  1. THE EVENT LOOP what is it…really?

  2. …

  3. HOW DOES JS WORK? JS Runtime Call Stack function foo

    () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  4. HOW DOES JS WORK? JS Runtime Call Stack main() function

    foo () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  5. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    function foo () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  6. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    bar() function foo () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  7. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    bar() function foo () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz(); foo()

  8. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    bar() function foo () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz(); foo() console.log()

  9. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    bar() function foo () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz(); foo()

  10. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    bar() function foo () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  11. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    function foo () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  12. HOW DOES JS WORK? JS Runtime Call Stack main() function

    foo () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  13. HOW DOES JS WORK? JS Runtime Call Stack function foo

    () { console.log("Hello World"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  14. HOW DOES JS WORK? JS Runtime Call Stack function foo

    () { throw new Error("Woops"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  15. HOW DOES JS WORK? JS Runtime Call Stack main() function

    foo () { throw new Error("Woops"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  16. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    function foo () { throw new Error("Woops"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  17. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    bar() function foo () { throw new Error("Woops"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  18. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    bar() foo() function foo () { throw new Error("Woops"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  19. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    bar() foo() function foo () { throw new Error("Woops"); } function bar () { return foo(); } function baz () { return bar(); } baz();

  20. HOW DOES JS WORK? JS Runtime Call Stack main() baz()

    bar() foo() function foo () { throw new Error("Woops"); } function bar () { return foo(); } function baz () { return bar(); } baz(); Stack Trace

  21. HOW DOES JS WORK? JS Runtime Call Stack function foo()

    { return foo(); } foo();

  22. HOW DOES JS WORK? JS Runtime Call Stack foo() function

    foo() { return foo(); } foo();

  23. HOW DOES JS WORK? JS Runtime Call Stack foo() function

    foo() { return foo(); } foo(); foo()

  24. HOW DOES JS WORK? JS Runtime Call Stack foo() function

    foo() { return foo(); } foo(); foo() foo()

  25. HOW DOES JS WORK? JS Runtime Call Stack foo() function

    foo() { return foo(); } foo(); foo() foo() foo()

  26. HOW DOES JS WORK? JS Runtime Call Stack foo() function

    foo() { return foo(); } foo(); foo() foo() foo() foo()

  27. HOW DOES JS WORK? JS Runtime Call Stack foo() function

    foo() { return foo(); } foo(); foo() foo() foo() foo() foo()

  28. HOW DOES JS WORK? JS Runtime Call Stack foo() function

    foo() { return foo(); } foo(); foo() foo() foo() foo() foo() foo()

  29. HOW DOES JS WORK? JS Runtime Call Stack foo() function

    foo() { return foo(); } foo(); foo() foo() foo() foo() foo() foo() foo()

  30. HOW DOES JS WORK? JS Runtime Call Stack foo() Stack

    Trace function foo() { return foo(); } foo(); foo() foo() foo() foo() foo() foo() foo()

  31. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 1000); console.log("Vegas JS"); Console

  32. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 1000); console.log("Vegas JS"); Console

  33. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 1000); console.log("Vegas JS"); console.log() Console

  34. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 1000); console.log("Vegas JS"); console.log() Console “Hello”

  35. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 1000); console.log("Vegas JS"); Console “Hello”

  36. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 1000); console.log("Vegas JS"); setTimeout() Console “Hello”

  37. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 1000); console.log("Vegas JS"); Console “Hello”

  38. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 1000); console.log("Vegas JS"); console.log() Console “Hello”

  39. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 1000); console.log("Vegas JS"); console.log() Console “Hello” “Vegas JS”

  40. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 1000); console.log("Vegas JS"); Console “Hello” “Vegas JS”

  41. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 1000); console.log("Vegas JS"); Console “Hello” “Vegas JS”

  42. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 1000); console.log("Vegas JS"); Console “Hello” “Vegas JS” console.log()

  43. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 1000); console.log("Vegas JS"); Console “Hello” “Vegas JS” “World” console.log()

  44. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 1000); console.log("Vegas JS"); Console “Hello” “Vegas JS” “World”

  45. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 0); console.log("Vegas JS"); Web/Node APIs Task Queue Event Loop

  46. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 0); console.log("Vegas JS"); Web/Node APIs Task Queue Event Loop

  47. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 0); console.log("Vegas JS"); console.log() Web/Node APIs Task Queue Event Loop

  48. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 0); console.log("Vegas JS"); Web/Node APIs Task Queue Event Loop

  49. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 0); console.log("Vegas JS"); setTimeout() Web/Node APIs Task Queue Event Loop

  50. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 0); console.log("Vegas JS"); setTimeout() Web/Node APIs Task Queue Event Loop

  51. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 0); console.log("Vegas JS"); setTimeout() Web/Node APIs Task Queue Event Loop

  52. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 0); console.log("Vegas JS"); setTimeout() console.log() Web/Node APIs Task Queue Event Loop

  53. HOW DOES JS WORK? JS Runtime Call Stack main() console.log("Hello");

    setTimeout(function(){ console.log("World"); }, 0); console.log("Vegas JS"); setTimeout() Web/Node APIs Task Queue Event Loop

  54. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 0); console.log("Vegas JS"); setTimeout() Web/Node APIs Task Queue Event Loop

  55. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 0); console.log("Vegas JS"); setTimeout() Web/Node APIs Task Queue Event Loop

  56. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 0); console.log("Vegas JS"); Web/Node APIs Task Queue Event Loop

  57. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 0); console.log("Vegas JS"); Web/Node APIs console.log() Task Queue Event Loop

  58. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 0); console.log("Vegas JS"); Web/Node APIs console.log() Task Queue Event Loop

  59. HOW DOES JS WORK? JS Runtime Call Stack console.log("Hello"); setTimeout(function(){

    console.log("World"); }, 0); console.log("Vegas JS"); Web/Node APIs Task Queue Event Loop

  60. *APPLAUSE* Thanks guys! References: https://youtu.be/8aGhZQkoFbQ Loupe: http://latentflip.com/loupe