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@futur
Last active May 22, 2021 02:34
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Understanding identifiers (valid and invalid) in JS. Simple examples.
var $ = {'4s':'4 times S', s4:'s times 4'}; // correct identifiers and valid.
// var _ = {4s:'4 times S', s4:'s times 4'}; // Error in 4s, as its not a valid identifier. coz identifiers cant start with numbers. so add quotes.
console.log($['4s']); // 4 times S - this works because 4s is basically invalid identifier and thus we enclosed with quotes to make it work
// console.log($.4s); //Error since the 4s is not a valid identifier anc . operator will ignore with error.
console.log($.s4); //s times 4
var object ={.12e34 : 'hey'}
console.log(object['.12e34']); //undefined
console.log(object[.12e34]); //hey
console.log(JSON.stringify(object)); //{"1.2e+33":"hey"}
//So internally .12e34 is stored as "1.2e+33", to prove this:
console.log(String(.12e34)); //1.2e+33
var myName = {பிரேம்:'குமார் '};
console.log(myName.பிரேம்);
console.log(JSON.stringify(myName));
//Ultimately, we understand that every identifier is checked for validity by the runtime internally then converted to a valid String.
@cameronapak
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Hey, thanks for creating this! Now I have a better understanding of identifiers. For some reason I was confused until I read your docs. Thanks!

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