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Classes & Generators: Can't combine?

See original GitHub issue

If you are reporting a bug, please fill in below. Otherwise feel free to remove this template entirely.

Can you reproduce the problem with latest npm?



When a script with both a js class and a generator are defined, compilation breaks.

Expected behavior

Compilation of script.

Actual behavior

Browser console logs error message “…Uncaught ReferenceError: _regeneratorRuntime is not defined”


npm ls react-scripts: my-app@0.1.0 /Users/angelbeltran/dev/test/my-app └── react-scripts@0.9.5

node -v: v7.0.0

npm -v: 4.5.0

  1. Operating system: MacOS Sierra, Version 10.12.4
  2. Browser and version: Google Chrome, 57.0.2987.133 (64-bit)

Reproducible Demo

I added a simple class and generator to src/index.js. Clone and enter the project, and run

npm start

When the browser opens, you’ll get the error message I got.

Issue Analytics

  • State:closed
  • Created 6 years ago
  • Comments:7 (5 by maintainers)

github_iconTop GitHub Comments

ianschmitzcommented, May 15, 2017

I could reproduce using react-scripts@0.9.5 with the same sample code provided by @angelbeltran. However I could not reproduce on latest master commit (5ecda24f76a0d64aba98f3f5059e25e1a9695ce6) using npm start.

Edit: Sorry didn’t see your post @gaearon

gaearoncommented, May 15, 2017

This does not reproduce in master. I’m assuming it was fixed by disabling CommonJS transform.

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