Hello, World! program for React Native throws "Could not parse the simulator list output" on Mac

Question

I just started learning React Native and was trying to run my Hello, World! app using the steps given in https://facebook.github.io/react-native/docs/getting-started.html#content

I took the following steps

1. `brew install watchman`
2. `npm install -g react-native-cli`
3. `react-native init hello`
4. `cd hello`
5. `react-native run-ios`

Instead of launching the iOS app, I got the following error in the terminal:

Found Xcode project hello.xcodeproj
Usage: simctl list [devices|devicetypes|runtimes]
Could not parse the simulator list output

I also tried to run it using Xcode; however Xcode shows lot of compilation errors.

Following are details on my system

1. OS: Mac OS v10.10.5 (Yosemite)
2. Node.js version: 4.4.1
3. Xcode version: Version 6.3 (6D554n)

Following is a screenshot of errors shown in Xcode.

Answer 1

Error disappeared after I launched Xcode and allowed to install some updates.

Answer 2

The problem was that I updated Xcode and never opened it after the update completed. After I opened Xcode it did install components then when I tried again it worked fine.

Answer 3

In my situation, I closed the current terminal and reopened it, then the error was gone.

Answer 4

I realized that I was using a beta version of Xcode. Once I installed the latest version of Xcode then all errors were gone and the app were launched in the simulator.