[racket] sharing an expensive computation required in procedure and its contract?

On Sun, Jul 20, 2014 at 2:47 PM, Alexander D. Knauth
<alexander at knauth.org> wrote:
>
> On Jul 20, 2014, at 1:56 PM, Jon Zeppieri <zeppieri at gmail.com> wrote:
>
>> I feel like this has come up before, but I can't seem to find the
>> discussion in the archive.
>
> Was this what you were thinking of?
> http://lists.racket-lang.org/users/archive/2013-November/060427.html
> http://lists.racket-lang.org/users/archive/2013-November/060429.html
> http://lists.racket-lang.org/users/archive/2013-November/060430.html
> http://lists.racket-lang.org/users/archive/2013-November/060433.html
> http://lists.racket-lang.org/users/archive/2013-November/060437.html
>

I think so, yes. But since everyone is agreed that this is a bad idea,
I'll go a different route. I'm perfectly happy to raise an exception
inside the procedure. Is raise-argument-error the preferred way?