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Underscores as number separators (JS Bits)

cilly_boloe profile image Billy Coloe ・1 min read

Making calculations with longer numbers? You can improve readability by using underscores (_) in numeric primitives:

// Hard to read:
Math.floor(Math.random() * 1000000); // 337083

// Better
Math.floor(Math.random() * 1_000_000); // 337083

1_000_000 === 1000000 // true
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The underscore doesn't have to be placed where a comma would go - it can be used anywhere in the number except at the very beginning or end. Just a small way to improve your code and prevent errors!

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Discussion (2)

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jankapunkt profile image
Jan Küster

How so you feel about the choice of the _ as separator?

kvetoslavnovak profile image

I guess it was a good neutral choice. Because many languages use many very different separators: commas, dots, spaces, ...