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Mark Matthew Vergara
Mark Matthew Vergara

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Understanding NaN Equality in JavaScript

Did you know NaN == Nan is actually false?

This might seem counterintuitive, but it's because NaN represents an indeterminate or undefined value. Therefore, it's impossible to equate two NaN values using the equality operator.

The correct way of checking for NaN is yung the isNan

console.log(Number.isNaN(NaN)); // True
console.log(isNaN(NaN)); // True
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these are built-in JavaScript function that checks if a value is NaN

I learned a lot from this video

Top comments (2)

mainarthur profile image
Arthur Kh

NaN Meme
Quick meme explaining what is NaN :D

mmvergara profile image
Mark Matthew Vergara

This should be on meme monday lmao.