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Sobio Darlington
Sobio Darlington

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Why does this work in javascript?

I just bumped into this. Anyone have insight as to why this works?

const a = {b: 2}; 

console.log( a[['b']] );

// Result: 2
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Top comments (3)

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Vivek B

Index(es) needs to be string and JS will automatically convert anything used as object's index to a string. ['b'].toString() happens to be equal to 'b' (its same as ['b'].join(',')).

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Sobio Darlington

Looks like it.

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Alexander P. • Edited

not sure if that's related but [['b']] appears to be equal to 'b'