[plt-scheme] HTDP Exercises and language levels

(draw-solid-disk (make-posn 10 10) 20 'red)
produces true.

(draw-solid-disk (make-posn 50 50) 40 'green)
produces true.

You want the first and the second expression to evaluate to true.
How can you force this to be the case?

Apologies for abusing and, but it offered itself. -- Matthias

P.S. I won't read any flames about the use of and for this purpose.

On Wednesday, November 19, 2003, at 09:35 AM, Guenther Schmidt wrote:

>  For list-related administrative tasks:
>  http://list.cs.brown.edu/mailman/listinfo/plt-scheme
>
> Hi,
>
> how do I find out which language level is supposed to be sufficient 
> for a current exercise?
>
> For instance:
>
> I'm trying to solve an exercise in Section 6.6 HTDP and I think I know 
> how to formulate the solution under an advanced language level, but I 
> have the feeling, as this would require recursion and / or other 
> things that have not yet been formally introduced yet, that this is 
> not what the authors had in mind.
>
> I've read through the previous over and over but couldn't find a hint 
> which would give away the language level.
>
> Best regards
>
> Guenther
>