[racket] multiple-value sugar in "let"* forms

> I asked about multiple-value "let"*.  All I wanted was to renovate my
> kitchen, but instead you're trying to sell me a downtown penthouse.  You're
> going to have to sell me on why I'd want the downtown lifestyle, and allay
> my concerns about social diseases.  We could just renovate my kitchen
> *while* you refine the downtown living story.

I will play the role of Ron Popeil: What every kitchen needs is this
handy knife I call `def'. ;)