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Comment by PretzelFisch | Hacker News Reader

I would like a null conditional operator and null coalescing operator.

return data?.error?.message ?? "no error";

Also pattern matching would be a big win.

Absolutely this. I've done work in both Swift and JS (well, Typescript) and every feature on my wishlist is from Swift. Null operator like you suggest, guard statements and structs, which are the best equivalent to value-type objects as outlined in the article.

Yep. Both are stage-1 proposals:

https://github.com/tc39/proposal-optional-chaining

https://github.com/tc39/proposal-nullish-coalescing

Recently started using optional chaining in our codebase (via Babel 7) and it's great so far. Also gives us proper static typing safety unlike Lodash `get(...)`

Null coalescing is already possible with ||. Though I'd like ?? If it worked for undefined coalescing as well.

You still have to be more verbose, though. You can't do obj1?.obj2 with ||, not could you do obj1?.method()

How does || differentiate null from e.g. 0 or ""?

It doesn't - it tests for a "truthy" value.

These are not the same.

    let val = 0
    val || 30 // 30
    
    val ?? 30 // 0

The same goes for other falsy values.

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