Guided Practice 6.1: Pizzas as Structures

There are two questions in this Guided Practice.

1. Write the three pizza functions from module 5 (replace-all-anchovies-with-onions, replace-all-anchovies, and replace-topping) using the data definition in this lesson.
2. You've been working at the pizza shop for a few months now, and you've written hundreds of functions manipulating pizzas. Your boss has now come under the spell of an evil wizard, who has convinced him that his business will be much better if he changes the data definition for pizza to the following:

   ;; A Topping is a String.
   ;; A Pizza is either
   ;; -- the string "kaphlooey"
   ;; -- (make-shazam Pizza Topping)
   
   ;; Interp:
   ;; "kaphlooey"        represents a pizza with no toppings
   ;; (make-shazam p t)  represents the pizza p with topping t added on top.
   

   What do you do to satisfy your insane boss?

[ANSWER]