How to type check a Date object in flow?

Question

I have a function that takes a Date object as its paramater. I am not able to figure out how to annotate this.

function diffDate (start: any, end:any) {
//....
}

How do I type annotate start and end as Date objects?

Solution

Thanks loganfsmyth and Nikita for the comments. It works as expected.

function diffDate (start: Date, end: Date) {
   // ...
}

Comments

[loganfsmyth]

Does : Date not work?

[Nikita]

It should because Flow comes with built-in definitions for Date class: github.com/facebook/flow/blob/master/lib/core.js#L364