Nullish Coalescing operator (??) support for upcoming TypeScript release

TypeScript 3.7.0-beta

WebStorm 2019.2.2

11 comments is fixed i n 2019.3

Nullish operator is correctly highlighted for me in 2019.3 EAP if the TypeScript language service is off:

By assertion expressions, do you mean They are also supported in 2019.3 (



Oh, crap... Yes, you're right Elena.

I had `Automatic TSLint configuration` in settings. After replaced with the `Manual...` one everything works fine. One idea I have now - TSLint version was updated while WebStorm was running, so it used previously installed version and show error. With update config, I triggered the restart of TSList and now it works.

Thank you very much :)


Nullish operator is supported since the upcoming 2019.3.

Please try 2019.3 EAP ( - does the issue persist?


As well as assertion expressions; I assume implementing beta features can be a waste of resources in case something changes before release, although for JavaScript nullish coalescing was implemented a year ago:

Can we have some clarification on how the process usually goes?


Our project just updated to TS@3.7.2 and I can see such error:

I'm using WebStorm 2019.3 EAP
Build #WS-193.4932.10, built on October 30, 2019
Runtime version: 11.0.4+10-b520.2 x86_64
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o
macOS 10.15
GC: G1 Young Generation, G1 Old Generation
Memory: 4096M
Non-Bundled Plugins: com.emberjs, com.intellij.ideolog, quokka.js


The only error in your screenshot comes from TSLint and doesn't look related to nullish operator; please hover over the operator and attach a screenshot of the error message


Nullish coalescing operator is incorrectly highlighted for me too.

I am using Typescript 3.7.2(and it shows this version as well in the typescript tab). The compilation is also working fine but the editor show this error

Since this feature is officially released, it should be fixed in the editor now


Works on 2.4 for me.

Now waiting on asserts release:)


It works!

Thanks Elena!


Something needs to be done on older versions.. 2019.1.4 is not fixed :(


we don't plan to patch old versions to make them compatible with each and every new Typescript feature, sorry


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