React: Prop Types example

gistfile1.txt

var React = require('react');

var Runner = React.createClass({
  propTypes: {
    message:   React.PropTypes.string.isRequired,
    style:     React.PropTypes.object.isRequired,
    isMetric:  React.PropTypes.bool.isRequired,
    miles:     React.PropTypes.number.isRequired,
    milesToKM: React.PropTypes.func.isRequired,
    races:     React.PropTypes.array.isRequired
  },

  render: function () {
  	var miles = this.props.miles;
    var km = this.props.milesToKM(miles);
    var races = this.props.races.map(function(race, i){
      return <li key={race + i}>{race}</li>;
    });

    return (
      <div style={this.props.style}>
        <h1>{this.props.message}</h1>
        { this.props.isMetric && 
          <h2>One Time I Ran {km} Kilometers!</h2> }
        { !this.props.isMetric && 
          <h2>One Time I Ran {miles} Miles!</h2> }
        <h3>Races I've Run</h3>
        <ul id="races">{races}</ul>
      </div>
    );
  }
});

// for Stateless functions...

var React = require('react');

function GuineaPigs (props) {
  var src = props.src;
    return (
      <div>
        <h1>Cute Guinea Pigs</h1>
        <img src={src} />
      </div>
    );
}

 GuineaPigs.propTypes = {
    src: React.PropTypes.string.isRequired
  };

module.exports = GuineaPigs;