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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <section id="coffee">
  <h1>Babel事始め</h1>
  <p>CodePen Settingの旅、JS編第4回。JS編の最後を飾るBabelはブラウザがまだ対応していない最新のESに準拠した記述ができるAltJSとのこと。
  </p>
  <section id="hello">
    <h2>特徴</h2>
    <ul>
      <li>最新のESに準拠</li>
      <li>変数にletやconstなどが使える</li>
     <li>アロー関数式「=>」が使える</li>
      <li>クラス定義ができる</li>
    </ul>
    <p>Babelも素のJSがそのまま行けるようなのでJSからの書き換えもしやすそう。</p>
    <p><small>※letは再宣言が出来ない。<br>
※constは再宣言も再代入もできない。<br>
 →いずれもvarより厳密だが、全てvarに置き換えても問題はない。
</small></p>
  </section>
  <div><button id="btn">ここ押せワンワン</button>
</section>
            
          
!
            
              #btn {
  display: inline-block;
padding: 1em;
background: #666;
border-radius: 5px;
  color: #fff;
}

#btn:hover {
  opacity: 0.7;
  cursor : pointer;
}
            
          
!
            
              /*関数
function hellow(){
window.alert('hellow TypeScript');
window.alert('こんにちは、型スクリプト');
window.alert('おしまい');
}*/

/*アロー関数*/
var hellow = () => {
window.alert('hellow Babel');
window.alert('こんにちは、バベル');
window.alert(title + 'は第' + num + '回です。');
window.alert('おしまい');
}



/*変数
var btn = document.getElementById('btn');*/

/*最新の変数*/
const btn = document.getElementById('btn');

let title = 'JS編';

var num = 4;

/*イベント*/
btn.addEventListener('click', hellow, false);
            
          
!
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