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Comment by a13n | Hacker News Reader

Super duper excited about optional chaining!

One thing I miss from Objective-C that I wish JS would add is the `?:` operator – basically a shortened version of the ternary operator.

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Optional chaining is moving through committee along with the "nullish coalescing operator" represented as `??`, which works like `||` except only falls through with `null` and `undefined`.

Do you mean

    true ? console.log("foo") : console.log("bar")

This is already there: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

  x ?: y

is shorthand for

  x != null ? x : y

Ah, thanks for the clarification. Did not know it is supported in some languages.

In JavaScript you can simply use the logical or operator

x || y

This is not equivalent. It will result in y if x is any falsy value (like false, empty string, or 0), not just if x is nullish.

In which languages does ?: not work that way?

For example in PHP, it works exactly like you describe.

I think that’s exactly what the nullish ?? Operator is.

You can write x ?? y

Which is x !== null and x != undefined ? x : y

Kotlin.

It’s more than simple ternary, for example: `response?.data?.users?[0]`

To get the first user from a server response would be significantly longer if you wrote three nested ternary operators.

How would this differ from the idiomatic "x || y"? Just s/non-zero/truthy

|| short circuits on falsey. 0, “”, false, null, undefined

?? Short circuits on nullish. Only null and undefined.

I think that's a GCC C extension, not an Objective-C feature.

Sure, I still miss it from Objective-C :P

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