What does the : symbol mean in React createClass() method?

Question

Here's some sample code from ReactKungfu:

var CommentBox = React.createClass({
  render: function() {
    return (
      <div className="commentBox">
        Hello, world! I am a CommentBox.
      </div>
    );
  }
});

What does the : in render: function() signify? I haven't seen this explained in vanilla JS tutorials I have done, although I believe it signifies "[something] in [this other list/range] in Java

It's just a normal object. The opening curly brace is at the end of the previous line. — JJJ, Nov 18 '18 at 21:41
@JJJ thanks! I kind of missed the JSON structure when I was staring at this for 15 mins — GPP, Nov 18 '18 at 22:41
That happens, although [it's not JSON](https://stackoverflow.com/a/2904181). — JJJ, Nov 18 '18 at 22:44
@JJJ fair point -- so reading from your link, is it accurate to say this `{render: ... }` is a JavaScript object literal? — GPP, Nov 18 '18 at 23:11

score 2 · Accepted Answer · answered Nov 18 '18 at 21:45

The curly brackets you put around the data passed into the function represent a JS object. render is simply a member variable of that object, so the : is to define that variable as the function after it.

It's basically equivalent to let render = function() { ... } outside of an object.

What does the : symbol mean in React createClass() method?

1 Answers1