PhpStorm "Let definition are not supported by current JavaScript version"

javascript phpstorm
Marc Rasmussen picture Marc Rasmussen · Mar 3, 2016 · Viewed 18k times · Source

I am trying to be a good little programmer and use the new tools available for coding JavaScript. Therefore I'm trying to use let instead of var to isolate variables.

This works fine in my browser however PhpStorm sees it as an error and when I hover above it gives me:

Let definition are not supported by current JavaScript version

So my question is how do I upgrade the current JavaScript version?

Answer

baao picture baao · Mar 3, 2016

Go to

Settings / Languages & Frameworks / JavaScript

(it may be Preferences / Languages & Frameworks / JavaScript on some OSes)

...and set the "JavaScript language version" to "ECMAScript 6" (or, if they've updated to reflect current naming, "ECMAScript 2015" — or "ECMAScript 2016" or later if you're coding to a newer spec):

enter image description here

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