anchor.diff:              }, 'Increment child value'),
             ]),
           ]),
  -        react.div({
  -          'key': 'callback-refs'
  -        }, [
  +        react.div({'key': 'callback-refs'}, [
             react.h2({'key': 'h2-callback'}, "Callback refs"),
             react.h4({'key': 'h4-callback-input'}, "<input>"),
             react.form({
  
positive.code:   }
  
    render() => react.div({}, [
          react.div({
            'key': 'string-refs'
          }, [
            react.h2({'key': 'string-h2'}, "String refs"),
            react.h4({'key': 'string-h4'}, "<input>"),
            react.form({
              'key': 'stringRefInputForm',
              'className': 'form-inline',
            }, [
              react.input({
                'key': 'string-input',
  
negative.code:           react.h4({'key': 'string-h4-child'}, "ChildComponent"),
            react.form({
              'key': 'stringRefChildComponentForm',
              'className': 'form-inline'
            }, [
              ChildComponent({'key': 'string-child', "ref": "childRef"}),
              '\u00a0',
              react.button({
                'type': 'button',
  