At no point does the author of this article actually look at the is-number package, or discuss it's contents. I don't know how to check if a Javascript object

At no point does the author of this article actually look at the is-number package, or discuss it's contents. I don't know how to check if a Javascript object is a number. I've seen various "javascript == and === and types really weird" videos, so I think I'd be tempted to just use an 'is-number' package, to be really sure I'm getting it right. So maybe the issue is that it's really hard to do basic things right in Javascript? The answer to this in most other languages would be to design a "standard library", then everyone would import that package, and while they would have just as much code, it would come in less pieces.