[racket] keyword arguments for type constructors?

On 2014-06-07 08:49:47 -0400, Matthias Felleisen wrote:
> I don't think we have type-alias definitions with keywords. But then
> again, I see no problem with this idea.

If we implement macros for types (type expanders ala match expanders)
then it would be possible to do something like this.

I tried implementing type expanders, but got stuck because of how
scoping works with syntax transformers and `local-expand`. When I have
more time I'll try again.

Cheers,
Asumu