[racket] why do I get undefined , when using internal definition?

On Sun, Jul 10, 2011 at 9:53 AM, Grant Rettke <grettke at acm.org> wrote:
> On Sun, Jul 10, 2011 at 1:49 AM, Eli Barzilay <eli at barzilay.org> wrote:
>> `define' is defining a potentially recursive value, so that
>>
>>  (define (loop) (loop))
>>
>> works as you expect.  In simple terms, you can think about an internal
>> define as something that expands to a `letrec'.  So what you wrote is
>> basically the same as
>>
>>  (define (make-color color)
>>    (letrec ([color color])
>>      ...))
>
> In what kind of situations would you use internal define over letrec?

Sorry I mean using define rather than a letrec explicitly.