The following code throws an error in javascript:

console.log(String( 0n))

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But this code runs successfully:

console.log(String(-0n))

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Why 0n throws an error but -0n does not?

CodePudding user response：

So that it doesn't break asm.js:

• Unary followed by an expression is always either a Number, or results in throwing. For this reason, unfortunately, on a BigInt needs to throw, rather than being symmetrical with on Number: Otherwise, previously "type-declared" asm.js code would now be polymorphic.

CodePudding user response：

0n is treated as (BigInt(0)), since unary means "cast to integer", and it can't automatically do that (for some reason)

console.log( (BigInt(0)));

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-0n is treated as BigInt(-0), since negative numbers can be big integers

(You need to check your console for this, since I guess there's a bug in the StackSnippets preventing BigInts from being casted to a string in the console.log call)

console.log(BigInt(-0));

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