undefined is not a function (evaluting optionalFlags[typeof Symbol === 'function'

[adirzoari]

Environment

OS: Windows 10
Node: 8.11.3
Yarn: 1.5.1
npm: 6.3.0
Watchman: Not Found
Xcode: N/A
Android Studio: Not Found

Packages: (wanted => installed)
react: 16.0.0-beta.5 => 16.0.0-beta.5
react-native: 0.49.3 => 0.49.3

Description

I worked on my project today, the project worked fine but then I exit from the app and try to run again and I got this error
undefined is not a function(evaluting 'optionalFlags[typeof Symbol === 'function' ? Symbol.iterator:

I saw many issues with same error, I tried to do some of them and nothing was helped.

[react-native-bot]

It looks like you are using an older version of React Native. Please update to the latest release, v0.57 and verify if the issue still exists.

The ":rewind:Old Version" label will be removed automatically once you edit your original post with the results of running react-native info on a project using the latest release.

[radko93]

Please provide repro steps.