Why is `this.state` not available by default?

[colllin]

I'm happy to move this question elsewhere if you can point me in the right direction.

Why do I get an error (Uncaught TypeError: Cannot read property 'someProperty' of null) when I don't call this.setState() before the initial render?

render() {
    return (
        <span>{this.state.someProperty}</span>
    )
}

This error goes away if I simply call this.setState() with an empty object in componentWillMount:

componentWillMount() {
    this.setState({});
}

Isn't this.state part of the core React Component API? Why wouldn't it be present by default?

[fkling]

See #1851 .

[jimfb]

Thanks @fkling! Closing this out in favor of #1851. Also, see #3236 (comment) which has a somewhat related discussion.

@colllin For future reference, usage questions are best addressed on StackOverflow. I know this was somewhat bug like, so this wasn't a bad place, but just something to consider; we try to keep github for tracking bugs in the core.

[colllin]

Thank you, @fkling