[racket] mysterious error message

Hi,

   I'm running DrRacket version 5.2.

   In Pretty Big, I get the following error message.

   The variable cl is highlighted in the definitions window, and in the 
interactions window the following text is displayed (partially in red).

   cl: expected cl in: cl

   In R5RS the code runs fine.

   What does this error message mean?  My guess is that it thinks that the 
function is receiving the wrong parameters, but that's incorrect.

   Thanks.

-Arthur

==============================================================
Arthur Nunes-Harwitt
Computer Science Department, Rochester Institute of Technology
Room 70-3509
585-475-4916
==============================================================

"I don't know what the language of the future will be
called, but it will look like LISP."

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