[racket] how to design programs chap5 error!!!

 > On Nov 28, 2010, at 6:58 AM, 邢泉 wrote:
 >
 >> Hi:
 >> Help Me! Thanks!
 >> > (master check-color)
 >> check-color: this is a procedure, so it must be applied to arguments
 >> (which requires using a parenthesis before the name)

On 11/29/10 10:10 PM, Matthias Felleisen wrote:
>
> How did you produce this error message?

My guess: Q. Xing defined master rather than using the master teachpack, 
which results in this error.

Make sure you add the master.ss teachpack by going to Language > Add 
Teachpack... then select master.ss.  Remove any definition of master 
that you have written.

David