[plt-scheme] HTDP Section 18 Pragmatics of local, Part 2

From: Marco Morazan (morazanm at gmail.com)
Date: Thu Apr 23 16:18:21 EDT 2009

> Thanks so much, but I am still not clear here. I understand star?very well,
> however how could (star? .........) be true when
> (last-occurrence s (rest alostars)) (rest alotars) is a list not a
> structure. That's what I have not yet understood.

But you are wrong......

The contract for last-occurence is:

    ;; last-occurrence : symbol list-of-star  ->  star or false

It never returns a list! :-)




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