craigmaloney's solution

to Bob in the Scheme Track

Test Suite


Bob is a lackadaisical teenager. In conversation, his responses are very limited.

Bob answers 'Sure.' if you ask him a question.

He answers 'Whoa, chill out!' if you yell at him.

He says 'Fine. Be that way!' if you address him without actually saying anything.

He answers 'Whatever.' to anything else.


Inspired by the 'Deaf Grandma' exercise in Chris Pine's Learn to Program tutorial. http://pine.fm/LearnToProgram/?Chapter=06

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.


;; Load SRFI-64 lightweight testing specification
(use-modules (srfi srfi-64))

;; Suppress log file output. To write logs, comment out the following line:
(module-define! (resolve-module '(srfi srfi-64)) 'test-log-to-file #f)

;; Require bob impl
(add-to-load-path (dirname (current-filename)))
(use-modules (bob))

;;; Begin test suite
(test-begin "bob-test")

(test-equal "responds-to-something"
            (response-for "To-may-to, tom-aaaah-to."))

(test-equal "responds-to-shouts"
            "Whoa, chill out!"
            (response-for "WATCH OUT!"))

(test-equal "responds-to-questions"
            (response-for "Does this cryogenic chamber make me look fat?"))

(test-equal "responds-to-forceful-talking"
            (response-for "Let's go make out behind the gym!"))

(test-equal "responds-to-acronyms"
            (response-for "It's OK if you don't want to go to the DMV."))

(test-equal "responds-to-forceful-questions"
            "Whoa, chill out!"
            (response-for "WHAT THE HELL WERE YOU THINKING?"))

(test-equal "responds-to-shouting-with-special-characters"
            "Whoa, chill out!"
            (response-for "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"))

(test-equal "responds to shouting numbers"
            "Whoa, chill out!"
            (response-for "1, 2 ,3, GO!"))

(test-equal "responds-to-shouting-wit-no-exclamation-mark"
            "Whoa, chill out!"
            (response-for "I HATE YOU"))

(test-equal "responds-to-statement-containing-question-mark"
            (response-for "Ending with ? means a question."))

(test-equal "responds-to-silence"
            "Fine. Be that way!"
            (response-for ""))

(test-equal "responds-to-prolonged-silence"
            "Fine. Be that way!"
            (response-for "     "))

(test-equal "responds-to-only-numbers"
            (response-for "1, 2, 3"))

(test-equal "responds-to-number-question"
            (response-for "4?"))

(test-end "bob-test")
;;; End test suite
(define-module (bob)
  #:export (response-for))

(use-modules (srfi srfi-1))

(define (blank-space? char-list) 
  (and-map (lambda (x) (char-whitespace? x)) char-list))

(define (response-for query)
  (let ((string-list (string->list query)))
    (let ((alpha-characters (filter char-alphabetic? string-list)))
        [(blank-space? string-list) "Fine. Be that way!"]
        [(and (not (eq? alpha-characters '()))
              (and-map char-upper-case? alpha-characters)) "Whoa, chill out!"]
        [(and (not (eq? string-list '()))
              (eq? #\? (last string-list))) "Sure."]
        [else "Whatever."]

What can you learn from this solution?

A huge amount can be learnt from reading other people’s code. This is why we wanted to give exercism users the option of making their solutions public.

Here are some questions to help you reflect on this solution and learn the most from it.

  • What compromises have been made?
  • Are there new concepts here that I could read more about to develop my understanding?