RegExp param for router.isActive

[Rokt33r]

router.isActive(/^\/hello/) would be great to deal with the problem like #3277
It makes the method much flexible and doesn't seem to destructive.

I know #3277 is due to wrong structure of routes.
But, it is quite annoying to take care about it when prototyping app.

I, therefore, prefer to use this.props.location.pathname.match(/^\hello/) for my new app.

[taion]

You can use whatever semantics you want in user space – checking the pathname explicitly like that is fine, if it's what your application requires.