Optional chaining on the left side in Javascript

Question

Is it possible to use the optional chaining operator in the left side of an assignment = in Javascript?

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Answer 1

It's not possible, sorry.

In the interest of a canonical answer: The MDN documentation isn't explicit about this, but you can read the proposal's README in GitHub for more information. It says:

The following is not supported, although it has some use cases; see Issue #18 for discussion:

• optional property assignment: a?.b = c

In the linked issue are the comments 1:

OK, seems like there's a rough agreement in this thread not to do the write case in the first iteration.

and 2:

We also discussed this question at TC39, and the committee did not seem so interested in adding this feature.

So I guess it's not likely to happen anytime soon.

Hope that helps; good luck!

Answer 2

No, it is not possible. The documentation clearly states

The optional chaining operator ?. permits reading the value of a property located deep within a chain of connected objects without having to expressly validate that each reference in the chain is valid.

Answer 3

I’ve tried this on Chrome Canary (because of the browser compatibility) and it didn’t work: