University of British Columbia CPSC 110 Problem set 4

;; DO NOT PUT ANYTHING PERSONALLY IDENTIFYING BEYOND YOUR CWL IN THIS FILE.

;; YOUR CWLs WILL BE SUFFICIENT TO IDENTIFY YOU AND, IF YOU HAVE ONE, YOUR

;; PARTNER.

(require 2htdp/universe)

(require 2htdp/image)

(require spd/tags)



(@assignment pset-04);Do not edit or remove this tag

(@cwl ??? ???) ;Replace ??? with your cwl,

;; ;second ??? is replaced with partner cwl if you have one



(@problem 1)

;; Design a data definition for a song. Each song has a name, an artist,

;; and a duration (the length of the song in seconds).

;;

;; Your design must follow all applicable recipes, and must include all

;; appropriate @tags. Solutions which "just work" but do not follow the design

;; recipes will receive few if any marks.



(@htdd Song)

(define-struct song (name artist duration))

;; Song is (make-song String String Natural)

;; interp. a song with a title (name), artist,

;; and length of time in seconds

(define S1 (make-song "Shape of You" "Ed Sheeran" 233))

(define S2 (make-song "Rockstar" "Post Malone" 218))

(define S3 (make-song "All of Me" "John Legend" 269))



(@dd-template-rules compound)

, (define (fn-for-song s)

(... (song-name s)

(song-artist s)

(song-duration s)))



(@problem 2)

;; Use your data definition from Problem 1 to complete this problem.

;;

;; Design a data definition for an arbitrary number of songs.

;;

;; Your design must follow all applicable recipes, and must include all

;; appropriate @tags. Solutions which "just work" but do not follow the design

;; recipes will receive few if any marks.



(@htdd ListOfSong)

;; ListOfSong is one-of:

;; - empty

;; - (cons Song ListOfSong)

;; interp. a list of songs

(define LOS0 empty)

(define LOS1 (cons S1 (cons S2 (cons S3 empty))))



(@dd-template-rules one-of

atomic-distinct

compound

ref

self-ref)