Uncaught SyntaxError: embedded: Unexpected token var Comment = React.createClass({...}); - reactjs

Hey great folks of Stack Overflow. I am learning REACTJS right now. And it's throwing this error: Uncaught SyntaxError: embedded: Unexpected token var Comment = React.createClass({...});
Here's my code: `
<body>
<div id="example">
</div>
<div id="container">
</div>
<script type="text/babel">
var Comment = React.createClass({...});
var Board = React.createClass({
getinitialState: function(){
return{
comments: [
"I like bacon.",
"Want to get ice cream?",
"Okay, we've got enough comments now."
]
}
},
render: function() {
return(
<div className="board">
{
this.state.comments.map(function(text, i){
return(<Comment key={i}>{text}</Comment>);
})
}
</div>
);
}
})
ReactDOM.render(<Board/>, document.getElementById("container"));
</script>
<script src="https://npmcdn.com/react#15.3.0/dist/react.min.js"></script>
<script src="https://npmcdn.com/react-dom#15.3.0/dist/react-dom.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-core/5.8.24/browser.js"></script> <!-- older transpiler 5.8.24 works with this app-->
</body>
`
I am not sure what's going on here. I'm trying to create a component via var Comment which should have an array which is "var Comment = React.createClass({..}); I don't know why it's not recognizing it as an array that would be used. I would definitely appreciate some help on this, good folks of StackOverflow.

You are writing your React code in JSX which is not understood by the script tag. In order to run the React code either use the webpack or browserify to bundle your jsx into a .js file and then include that .js file in the script tag or in order to test your code use the JSFIDDLE to write your code . It has integration for JSX.
Sample webpack.config.js
var webpack = require('webpack');
var path = require('path');
var BUILD_DIR = path.resolve(__dirname, 'src');
var APP_DIR = path.resolve(__dirname, 'src');
var config = {
entry: APP_DIR + '/index.jsx',
output: {
path: BUILD_DIR,
filename: 'bundle.js'
}
};
module.exports = config;
index.jsx
import React from 'react';
import ReactDOM from 'react-dom';
var Board = React.createClass({
getinitialState: function(){
return{
comments: [
"I like bacon.",
"Want to get ice cream?",
"Okay, we've got enough comments now."
]
}
},
render: function() {
return(
<div className="board">
{
this.state.comments.map(function(text, i){
return(<Comment key={i}>{text}</Comment>);
})
}
</div>
);
}
})
ReactDOM.render(<Board/>, document.getElementById("container"));
index.html
<body>
<div id="example">
</div>
<div id="container">
</div>
<script src="./src/bundle.js"></script>
</body>
You also need to have a package.json to provide all the dependencies.
Here is a good video tutorial series that can help you with all the configuration

JSX syntax is not understood by the script tag. The JSX needs to be compiled to JavaScript. Try out your example in JSFiddle. JSFiddle has integration scripts to work with React.
<script src="https://facebook.github.io/react/js/jsfiddle-integration-babel.js">
</script>

You can try moving your JSX code to a new .jsx file and referencing that file in your .html

I met the same problem with you, seems we were watching the same tutorial video :)
Anyway, getinitialState should be getInitialState. Watch out the 4th letter.

Do the one change in your snippet codes which it is given in above section.
Correct minor spelling mistake here.
getinitialState() should be getInitialState().
ES5 use getInitialState() to initialize the state variables i.e React.createClass(..).
ES6 use constructor() to initialized the state variables i.e class Comment extends React.Component(..)
Here is another example of ES6, please check out this.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width">
<title></title>
</head>
<body>
<div id="content"></div>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-standalone/6.24.0/babel.js"></script>
<script src='https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.min.js'></script>
<script type="text/babel">
class CommentBox extends React.Component{
constructor(props){
super(props);
this.state = {
editable : false,
commentMsg : ">>"
};
}
save(event){
this.setState({commentMsg:event.target.value})
}
remove(){
this.setState({
editable:false
})
}
edit(){
this.setState({
editable:true
})
}
renderForm(){
return (
<div className="row">
<div>{this.props.children}</div>
<div><textArea name="commentBox" onChange={this.save.bind(this)}></textArea></div>
<button type="button" className="btn btn-danger">Save</button>
<button type="button" className="btn btn-success" onClick={this.remove.bind(this)}>Remove</button>
{this.state.commentMsg}
</div>
);
}
renderHtml(){
return (
<div className="row">
<div>{this.props.children}</div>
<div>{this.state.commentMsg}</div>
<button type="button" className="btn btn-danger" onClick={this.edit.bind(this)}>Edit</button>
<button type="button" className="btn btn-success" onClick={this.remove.bind(this)}>Remove</button>
</div>
);
}
render() {
if(this.state.editable){
return this.renderForm(this);
}else{
return this.renderHtml(this);
}
}
}
class Board extends React.Component{
constructor(props){
super(props);
this.state ={
comments:[
'Techical Comments',
'Wordpress Comments',
'Facebook Comments'
]
}
}
render(){
return(
<div className="container-fluid">{
this.state.comments.map(function(text,i){
return (
<CommentBox key={i}>{text}</CommentBox>
);
})
}
</div>
);
}
}
ReactDOM.render(
<Board />
, document.getElementById('content'))
</script>
</body>
</html>

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As you can see this is VS2017 MVC simple test application.
Actually, in VS editor I have some complaints that is shown on the screen shot bellow:
How to fix it and run it?
Change your script type as <script type="text/babel">
sample code :
<html>
<head>
<title>demo</title>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.4.2/react.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.4.2/react-dom.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-standalone/6.21.1/babel.min.js"></script>
</head>
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constructor(props){
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);
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}
buttonClicked(evt) {
alert("hi");
}
render() {
let msg = this.state.message;
return (
<div>
<label>Name: <input type="text" /></label>
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