How to type check a Date object in flow?
<p>I have a function that takes a Date object as its paramater. I am not able to figure out how to annotate this. </p>

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<pre class="snippet-code-js lang-js prettyprint-override"><code>function diffDate (start: any, end:any) {
//....
}</code></pre>
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How do I type annotate <code>start</code> and <code>end</code> as Date objects?</p>