JavaScript Quiz Part 3

If you miss the part 1 and part 2 check out part1,part2

  1. [ ]+{ }

  2. [ ]+0

  3. { }+1

  4. [ ]-0

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That's all there is to say about those things... See this brilliant talk:

Try with this too:

  • [1] - 0
  • [1] + 1
  • [1] - 1
  • [1, 2] - 0
  • 1 + {}
  • [1] + {}

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  1. I Suspected but got wrong.
  2. I got it right
  3. Never expected that to happen
  4. Obviously i expected

Wrong on the first one, definitly not expected that.

My answers, 50%:

  1. [{}] // Wrong
  2. [0] // Wrong
  3. 1 // Right
  4. 0 // Right

How does this happen? Can anyone explain? :O

The + operator can either concatenate two elements or perform an addition.

In the first case, it will convert both elements to strings, the array being an empty string and the second one being [Object object].

Second does pretty much the same thing, [] = '', 0 = '0', '' + '0' = '0'
And the others are similar.

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