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Some quizzes for JavaScript quirks.
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sort: most accepted
1. Promise order
JavaScript
Promise
1268 accepted
2. Promise executor
JavaScript
Promise
1243 accepted
3. Promise then callbacks
JavaScript
Promise
783 accepted
5. block scope
JavaScript
709 accepted
7. Increment Operator
JavaScript
541 accepted
4. Promise then callbacks II
JavaScript
Promise
533 accepted
70. function
JavaScript
479 accepted
69. undefined
JavaScript
458 accepted
8. Implicit Coercion I
JavaScript
385 accepted
6. Arrow Function
JavaScript
377 accepted
10. Equal
JavaScript
311 accepted
61. onClick
JavaScript
278 accepted
27. Hoisting I
JavaScript
278 accepted
9. null and undefined
JavaScript
267 accepted
12. arguments
JavaScript
261 accepted
63. in
JavaScript
251 accepted
67. if
JavaScript
249 accepted
39. var
JavaScript
246 accepted
28. Hoisting II
JavaScript
239 accepted
86. setTimeout III
JavaScript
237 accepted
68. if II
JavaScript
221 accepted
29. Hoisting III
JavaScript
220 accepted
65. Function name
JavaScript
217 accepted
13. Operator precedence
JavaScript
211 accepted
74. Typed Array length
JavaScript
188 accepted
37. push unshift
JavaScript
187 accepted
17. reduce
JavaScript
181 accepted
72. Array length
JavaScript
180 accepted
44. Function call
JavaScript
173 accepted
45. Hoisting VI
JavaScript
169 accepted
41. `this` III
JavaScript
167 accepted
54. setTimeout(0ms)
JavaScript
166 accepted
11. Implicit Coercion II
JavaScript
163 accepted
23. Promise.all()
JavaScript
158 accepted
38. Hoisting IV
JavaScript
154 accepted
18. Promise executor II
JavaScript
149 accepted
50. async await
JavaScript
137 accepted
15. instanceOf
JavaScript
137 accepted
60. postMessage
JavaScript
135 accepted
46. Implicit Coercion IV
JavaScript
135 accepted
19. `this`
JavaScript
135 accepted
64. reference type
JavaScript
134 accepted
53. Prototype 2
JavaScript
134 accepted
22. min max
JavaScript
134 accepted
62. MessageChannel
JavaScript
124 accepted
33. `this` II
JavaScript
124 accepted
32. Hoisting IIII
JavaScript
120 accepted
59. override setter
JavaScript
115 accepted
47. Promise Order II
JavaScript
114 accepted
48. Prototype
JavaScript
112 accepted
14. Addition vs Unary Plus
JavaScript
111 accepted
24. Equality & Sameness
JavaScript
106 accepted
77. parseInt 2
JavaScript
105 accepted
16. parseInt
JavaScript
105 accepted
26. true or false
JavaScript
103 accepted
49. `this` IV
JavaScript
102 accepted
21. Array I
JavaScript
97 accepted
36. Promise.prototype.finally()
JavaScript
92 accepted
20. name for Function expression
JavaScript
92 accepted
57. non-writable
JavaScript
88 accepted
73. window name
JavaScript
87 accepted
42. Hoisting V
JavaScript
85 accepted
52. requestAnimationFrame
JavaScript
82 accepted
84. Array.prototype.sort()
JavaScript
81 accepted
34. precedence
JavaScript
77 accepted
81. setTimeout II
JavaScript
76 accepted
25. zero
JavaScript
76 accepted
40. RegExp.prototype.test
JavaScript
75 accepted
71. two-way generator
JavaScript
73 accepted
58. inherit getter setter
JavaScript
72 accepted
55. sparse array
JavaScript
72 accepted
30. Equal II
JavaScript
72 accepted
31. Math
JavaScript
67 accepted
76. const
JavaScript
63 accepted
75. meaningless calculation
JavaScript
63 accepted
66. comma
JavaScript
61 accepted
43. JSON.stringify()
JavaScript
61 accepted
79. Equal III
JavaScript
51 accepted
51. method
JavaScript
48 accepted
85. String.raw()
JavaScript
46 accepted
87. instanceOf 2
JavaScript
44 accepted
56. to primitive
JavaScript
44 accepted
35. Implicit Coercion III
JavaScript
44 accepted
88. try...catch
JavaScript
38 accepted
89. let
JavaScript
36 accepted
83. Plus Plus
JavaScript
36 accepted
78. RegExp
JavaScript
RegExp
18 accepted
80. Proxy I
JavaScript
17 accepted
82. Proxy II
JavaScript
16 accepted
90. array keys
JavaScript
11 accepted