Incremental Testing of Procedures

• This assignment repeatedly adds functionality to the movie database query system by incrementally adding features to the matches? and substitutions-in-to-match procedures.

• These procedures are not allowed to be re-defined in a file using Scheme's define form.

• Instead, you will define separate procedures specifically for the exercises that use them.

• For example, matches? is modified for exercise 7.29, so assignment4.scm contains the following definition:

    (define matches?-for-7.29
      (lambda (pattern question)
  
        (define matches?
          (lambda (pattern question)
            "definition of matches? for exercise 7.29 goes here"))
  
        (matches? pattern question)))
  

• Note that your definition of matches? is internal to the definition of matches?-for-7.29.

• When you are ready to test exercise 7.29, the definition of matches?-for-7.29 will be used.

• This method of redefining previously defined procedures will be used throughout this assignment.