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Discussion on: JavaScript Amazing operators

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taufik_nurrohman profile image
Taufik Nurrohman •

Keep in mind:

let a, b = 1;
a ?? b; // → 1
a || b; // → 1
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let a = null, b = 1;
a ?? b; // → 1
a || b; // → 1
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let a = false, b = 1;
a ?? b; // → false
a || b; // → 1
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let a = 0, b = 1;
a ?? b; // → 0
a || b; // → 1
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let a = "", b = 1;
a ?? b; // → ""
a || b; // → 1
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  • ?? for null and undefined only.
  • || for falsy values such as "", 0 and false but also includes null and undefined as well.
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capscode profile image
capscode •

Hey Hi,
Thanks for adding this...
shall I add this to my blog ? what say ?

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taufik_nurrohman profile image
Taufik Nurrohman •

It’s up to you.

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nikla profile image
Nikla • • Edited

I think the post would benefit from also mentioning it. These two are easy to mix up and use incorrectly.