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Discussion on: Who can explain this deceptively simple destructuring assignment?

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stereobooster profile image
stereobooster • • Edited

You miss semicolon

var b = {};
[b] = [3]
console.log("b->",b)
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this would work as expected. It is easy to discover, if you use let:

let b = {}
[b] = [3]
console.log("b->",b)
// Uncaught ReferenceError: can't access lexical declaration 'b' before initialization
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Original code:

var b = {}
[b] = [3]
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which is the same as

var b = {}[b] = [3]
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which is the same as

var b = [3]
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cabrouwers profile image
CABrouwers • • Edited

Thanks a lot. It seemed absurd to me. All makes sense now!

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myleftshoe profile image
myleftshoe •

Wow, nice spot, and worrying for me because I never use semicolons anymore. But I also almost never use var. I guess I've been luck so far.