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denysdovhan / wtfjs

🤪 A list of funny and tricky JavaScript examples
http://bit.ly/wtfjavascript
Do What The F*ck You Want To Public License
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Holes and Trailing Commas in Array #29

Closed aemkei closed 7 years ago

aemkei commented 7 years ago

Here is another "funny" thing:

a = [,,,];
a.length // ==> 3
a + "" // ==> ",,"

see: https://twitter.com/aemkei/status/870252223762243584 and https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Trailing_commas

denysdovhan commented 7 years ago

Added! Thanks!