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reactjs - forEach() in React JSX does not output any HTML

I have a object that I want to output via React:

question = {
    text: "Is this a good question?",
    answers: [
       "Yes",
       "No",
       "I don't know"
    ]
} 

and my react component (cut down), is another component

class QuestionSet extends Component {
render(){ 
    <div className="container">
       <h1>{this.props.question.text}</h1>
       {this.props.question.answers.forEach(answer => {     
           console.log("Entered");  //This does ifre                       
           <Answer answer={answer} />   //THIS DOES NOT WORK 
        })}
}

export default QuestionSet;

as you can see from the snippit above, i'm trying to insert an array of the component Answer by using the array Answers in props, it does itterate but is not outputted into HTML.

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1 Answer

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by (71.8m points)

You need to pass an array of element to jsx. The problem is that forEach does not return anything (i.e it returns undefined). So it's better to use map because map returns an array:

class QuestionSet extends Component {
render(){ 
    <div className="container">
       <h1>{this.props.question.text}</h1>
       {this.props.question.answers.map((answer, i) => {     
           console.log("Entered");                 
           // Return the element. Also pass key     
           return (<Answer key={answer} answer={answer} />) 
        })}
}

export default QuestionSet;

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