<p dir="auto"><a href="https://babeljs.io/repl/#?experimental=true&amp;evaluate=true&amp;loose=true&amp;spec=false&amp;playground=true&amp;code=console.log(%2Bundefined)%3B%0A" rel="nofollow">https://babeljs.io/repl/#?experimental=true&amp;evaluate=true&amp;loose=true&amp;spec=false&amp;playground=true&amp;code=console.log(%2Bundefined)%3B%0A</a></p>
<p dir="auto">IIRC, this may already be tracked in another bug, but I couldn't find it. So apologies if dupe.</p>
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<p dir="auto">This kind of thing is strange and misleading:</p>
<p dir="auto"><a target="_blank" rel="noopener noreferrer nofollow" href="https://cloud.githubusercontent.com/assets/150330/7103416/5a865e58-e074-11e4-881d-fd6e47800938.png"><img src="https://cloud.githubusercontent.com/assets/150330/7103416/5a865e58-e074-11e4-881d-fd6e47800938.png" alt="screen shot 2015-04-11 at 5 56 05 pm" style="max-width: 100%;"></a></p>
<p dir="auto"><code class="notranslate">null</code> and <code class="notranslate">undefined</code> are definitely not the same value. ;-)</p>