[racket] list in Beginning Student

From: Prabhakar Ragde (plragde at uwaterloo.ca)
Date: Sat Oct 1 19:28:54 EDT 2011

On 10/1/11 8:33 AM, Todd O'Bryan wrote:
> I actually wish it weren't in there. One student discovers it, and
> lots of students start using list instead of cons ... empty. That
> wouldn't be a problem except that most of them don't have the
> conceptual chops yet and I have to fix their confusion.

Yes. I have noticed confusion of (list x y) and (cons x y). And I still 
don't know where they get (append (list x) y) and how to prevent it.

Another thing I might take out is `reverse'. They tend to use it to fix 
up recursions that they've gotten wrong. They can't write an efficient 
version using the templates, and they think that every built-in function 
is "free" in some sense, even as they carp about having to, say, do two 
recursive computations on the same list instead of putting them in "one 

But right now I am marking proofs they have done, after which it will be 
a pleasure to get back to mere programming errors. --PR

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