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Some quizzes for JavaScript quirks.
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easiest
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sort: most tried
1. Promise order
JavaScript
Promise
3703 tried
76. const
JavaScript
2060 tried
3. Promise then callbacks
JavaScript
Promise
1925 tried
70. function
JavaScript
1651 tried
5. block scope
JavaScript
1601 tried
4. Promise then callbacks II
JavaScript
Promise
1538 tried
6. Arrow Function
JavaScript
1509 tried
2. Promise executor
JavaScript
Promise
1471 tried
12. arguments
JavaScript
1357 tried
8. Implicit Coercion I
JavaScript
1216 tried
7. Increment Operator
JavaScript
1190 tried
68. if II
JavaScript
1183 tried
67. if
JavaScript
965 tried
9. null and undefined
JavaScript
900 tried
10. Equal
JavaScript
792 tried
27. Hoisting I
JavaScript
757 tried
61. onClick
JavaScript
699 tried
69. undefined
JavaScript
696 tried
17. reduce
JavaScript
667 tried
54. setTimeout(0ms)
JavaScript
648 tried
73. window name
JavaScript
637 tried
29. Hoisting III
JavaScript
600 tried
65. Function name
JavaScript
566 tried
42. Hoisting V
JavaScript
564 tried
72. Array length
JavaScript
524 tried
23. Promise.all()
JavaScript
523 tried
11. Implicit Coercion II
JavaScript
519 tried
38. Hoisting IV
JavaScript
506 tried
20. name for Function expression
JavaScript
506 tried
28. Hoisting II
JavaScript
505 tried
32. Hoisting IIII
JavaScript
500 tried
86. setTimeout III
JavaScript
481 tried
21. Array I
JavaScript
479 tried
84. Array.prototype.sort()
JavaScript
477 tried
63. in
JavaScript
461 tried
64. reference type
JavaScript
456 tried
50. async await
JavaScript
442 tried
39. var
JavaScript
428 tried
41. `this` III
JavaScript
424 tried
55. sparse array
JavaScript
417 tried
13. Operator precedence
JavaScript
389 tried
77. parseInt 2
JavaScript
385 tried
19. `this`
JavaScript
370 tried
74. Typed Array length
JavaScript
366 tried
15. instanceOf
JavaScript
356 tried
14. Addition vs Unary Plus
JavaScript
356 tried
43. JSON.stringify()
JavaScript
353 tried
16. parseInt
JavaScript
343 tried
51. method
JavaScript
340 tried
37. push unshift
JavaScript
340 tried
36. Promise.prototype.finally()
JavaScript
339 tried
62. MessageChannel
JavaScript
332 tried
22. min max
JavaScript
330 tried
47. Promise Order II
JavaScript
324 tried
60. postMessage
JavaScript
322 tried
45. Hoisting VI
JavaScript
319 tried
18. Promise executor II
JavaScript
312 tried
44. Function call
JavaScript
293 tried
33. `this` II
JavaScript
292 tried
25. zero
JavaScript
284 tried
85. String.raw()
JavaScript
260 tried
49. `this` IV
JavaScript
260 tried
26. true or false
JavaScript
246 tried
53. Prototype 2
JavaScript
244 tried
48. Prototype
JavaScript
243 tried
24. Equality & Sameness
JavaScript
243 tried
46. Implicit Coercion IV
JavaScript
233 tried
59. override setter
JavaScript
216 tried
52. requestAnimationFrame
JavaScript
212 tried
81. setTimeout II
JavaScript
210 tried
88. try...catch
JavaScript
195 tried
57. non-writable
JavaScript
185 tried
87. instanceOf 2
JavaScript
174 tried
56. to primitive
JavaScript
174 tried
58. inherit getter setter
JavaScript
168 tried
30. Equal II
JavaScript
163 tried
83. Plus Plus
JavaScript
146 tried
34. precedence
JavaScript
146 tried
75. meaningless calculation
JavaScript
143 tried
71. two-way generator
JavaScript
138 tried
35. Implicit Coercion III
JavaScript
138 tried
31. Math
JavaScript
135 tried
40. RegExp.prototype.test
JavaScript
134 tried
78. RegExp
JavaScript
RegExp
130 tried
66. comma
JavaScript
122 tried
89. let
JavaScript
112 tried
79. Equal III
JavaScript
77 tried
82. Proxy II
JavaScript
66 tried
90. array keys
JavaScript
61 tried
80. Proxy I
JavaScript
57 tried
91. largest Array index
new
JavaScript
3 tried