No way to do required arguments(?)

[lahwran]

That I could find, anyway. I searched the repository for "require" and found nothing.

[tailhook]

There is a required() method. I've added docs to README. Please, close the issue when you think that documentation is clear enough.

[lahwran]

It'd be super cool to have rustdoc documentation, but cool, I found it.

[tailhook]

I don't like rustdoc because it has documentation embedded in source code. And documentation should have much different structure than code. But I may be happy if anyone wants to contribute rustdoc documentation.