var Content=React.createClass({
            render: function(){
                return 
content
            }
        });
        
        var Comment=React.createClass({
            getInitialState: function(){
                return {
                    name:['tim','John','Jack']
                }
            },
            render: function(){
                var options=[];
                for(var i=0 ;i<=this.state.name.length; i++){
                    options.push({this.state.name[i]});
                }
                return 

                            
                                {options}
                            
                    
                    
                
                
            }
        });

上面的代码效果出来了，但是报了下面这个错，刚刚接触react，有点儿不理解，还请各位指教：
Warning: Each child in an array or iterator should have a unique "key" prop. Check the render method of Comment. See https://fb.me/react-warning-keys for more information.