[plt-scheme] is this a deep list ?

From: richard gere (diggerrrrr at gmail.com)
Date: Sun Mar 30 14:59:41 EDT 2008

Since this is my first posting i want to first  thank the authors of
htdp for such a wonderful book.
I also want to confirm to you that i am not a "student" in any school
or college.

>From ex 11.2.4
A deep-list is either
1. s where s is a symbol or
2. (cons dl empty) where dl is deep-list

Now from 1 we can say 'doll is a deep-list
>From 2 we can say (cons 'doll empty) is a deep list
>From 2 we can say (cons (cons 'doll empty) empty ) is a deep list
since it is in the form (cons dl empty)

Now is this a deep list , (my understanding is that it is  not
deep-list as per defination) :

(cons  (cons 'doll (cons 'robot empty)) empty)

why , well for it to be a deep-list the middle part has also to be a deep-list .
But middle part is in the form (cons 'doll dl)  i.e cons follwed by a
symbol followed by a deep-list and as per defination
there is no match , hence it is not a deep-list.

Please confirm if my reasoning is correct for this deep-list as per
defination given in the book

Thank you

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