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   Sergey on FunctionalScript (functionalscript@techhub.social)'s status on Thursday, 25-Jan-2024 04:41:20 JST Sergey on FunctionalScript

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   • Nicholas C. Zakas

   @nzakas thank you! Good to know. I always have a problem with the NaN name, I would better call it undefinedNumber, like in math. But, we can't change IEEE 754. I guess.

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     Nicholas C. Zakas (nzakas@fosstodon.org)'s status on Thursday, 25-Jan-2024 04:41:22 JST Nicholas C. Zakas

     JavaScript tip: Number.isNaN() is not the same as isNaN().

     Number.isNaN() checks if the value is exactly equal to NaN:

     Number.isNaN(NaN) === true;
     Number.isNaN("foo") === false;

     isNaN() checks if the value isn't a number:

     isNaN(NaN) === true;
     isNaN("foo") === true;