Overkill

When is it okay to build an orbital laser to destroy an ant-hill?

Many cry "overkill" when design principles are applied to trivial problems. And for good reason: in the context of work, excessive embellishment gets us into trouble. Complexity costs us time and money.

This talk explores how stepping outside of the realm of work and applying outrageous engineering practices to toy problems can deepen our understanding of the trade-offs that we make. Comically simple problems provide the perfect ground for developing actionable heuristics which can be applied to those monstrous complexities that we face in the real world.

Transcript

1. Katrina Owen
   @kytrinyx
   http://exercism.io
   Overkill
   

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3. 1
   2
   ...
   3563
   3564
   class Thing
   #...
   end
   /app/models/thing.rb
   

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4. 
   

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5. Oh. Shit.
   

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6. 1
   2
   ...
   3563
   3564
   class Thing
   #...
   end
   /app/models/thing.rb
   

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7. 1
   2
   ...
   3532
   3533
   class Thing
   #...
   end
   /app/models/thing.rb
   

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8. something
   different
   

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9. README
   

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

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11. README
    

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12. README
    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.
    

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13. test suite
    

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14. test suite
    

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15. test suite
    "Does this cryogenic chamber
    make me look fat?"
    Sure.
    

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16. test suite
    

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17. test suite
    "WATCH OUT!"
    Whoa, chill out!
    

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18. test suite
    

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19. test suite
    ""
    Fine. Be that way!
    

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20. test suite
    

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21. test suite
    "Tom-ay-to, tom-aaaah-to."
    Whatever.
    

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22. edge cases
    test suite
    

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23. test suite
    

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24. test suite
    "Ending with ? means a
    question."
    Whatever.
    

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25. test suite
    

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26. test suite
    "I HATE YOU"
    Whoa, chill out!
    

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27. test suite
    

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28. test suite
    "Let's go make out behind
    the gym!"
    Whatever.
    

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29. test suite
    

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30. test suite
    "WHAT THE HELL WERE YOU
    THINKING?"
    Whoa, chill out!
    

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31. test suite
    

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32. test suite
    "1, 2, 3"
    Whatever.
    

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33. test suite
    

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34. test suite
    "1, 2, 3 GO!"
    Whoa, chill out!
    

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35. test suite
    

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36. test suite
    "4?"
    Sure.
    

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37. test suite
    

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38. test suite
    "ZOMG THE %^*@#$(*^ ZOMBIES
    ARE COMING!!11!!1!"
    Whoa, chill out!
    

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39. code
    

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40. code
    24 iterations
    

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41. class Bob
    def hey (input )
    if input=="Tom-ay-to, tom-aaaah-to."
    return"Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input== "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    Iteration #1
    

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42. return"Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input== "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input==""
    return"Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input==" "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno
    return"Whatever."
    end
    end
    end
    Iteration #1
    

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43. class Bob
    def hey (input )
    if input=="Tom-ay-to, tom-aaaah-to."
    return"Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input== "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input =="1, 2, 3"
    return "Whatever."
    elsif input=="4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return"Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input== "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input==""
    return"Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input==" "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return"Whatever."
    end
    end
    end
    Iteration #1
    

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44. class Bob
    def hey (input )
    if input=="Tom-ay-to, tom-aaaah-to."
    return"Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input== "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input =="1, 2, 3"
    return "Whatever."
    elsif input=="4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return"Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input== "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input==""
    return"Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input==" "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return"Whatever."
    end
    end
    end
    Iteration #1
    

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45. class Bob
    def hey (input )
    if input=="Tom-ay-to, tom-aaaah-to."
    return"Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input== "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input =="1, 2, 3"
    return "Whatever."
    elsif input=="4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return"Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input== "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input==""
    return"Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input==" "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return"Whatever."
    end
    end
    end
    Iteration #1
    

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46. class Bob
    def hey (input )
    if input=="Tom-ay-to, tom-aaaah-to."
    return"Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input== "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input =="1, 2, 3"
    return "Whatever."
    elsif input=="4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return"Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input== "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input==""
    return"Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input==" "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return"Whatever."
    end
    end
    end
    Iteration #1
    

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47. class Bob
    def hey (input )
    if input=="Tom-ay-to, tom-aaaah-to."
    return"Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input== "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input =="1, 2, 3"
    return "Whatever."
    elsif input=="4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return"Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input== "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input==""
    return"Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input==" "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return"Whatever."
    end
    end
    end
    Iteration #1
    

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48. Iteration #1
    class Bob
    def hey (input )
    if input=="Tom-ay-to, tom-aaaah-to."
    return"Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input== "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input =="1, 2, 3"
    return "Whatever."
    elsif input=="4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return"Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input== "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input==""
    return"Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input==" "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return"Whatever."
    end
    end
    end
    

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49. class Bob
    def hey(input)
    if input == "Tom-ay-to, tom-aaaah-to."
    return "Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input == "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3"
    return "Whatever."
    elsif input == "4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return "Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input == "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input == ""
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return "Whatever."
    end
    end
    end
    Iteration #1
    class Bob
    def hey (input )
    if input=="Tom-ay-to, tom-aaaah-to."
    return"Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input== "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input =="1, 2, 3"
    return "Whatever."
    elsif input=="4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return"Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input== "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input==""
    return"Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input==" "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return"Whatever."
    end
    end
    end
    

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50. take-away #1
    

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51. take-away #1
    whitespace is meaningful
    

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52. Iteration #2
    class Bob
    def hey(input)
    if input == "Tom-ay-to, tom-aaaah-to."
    return "Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input == "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3"
    return "Whatever."
    elsif input == "4?"
    return "Sure."
    

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53. Iteration #2
    class Bob
    def hey(input)
    if input == "Tom-ay-to, tom-aaaah-to."
    return "Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input == "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3"
    return "Whatever."
    elsif input == "4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return "Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input == "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input == ""
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return "Whatever."
    end
    end
    end
    

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54. Iteration #2
    class Bob
    def hey(input)
    if input == "Tom-ay-to, tom-aaaah-to."
    return "Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input == "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3"
    return "Whatever."
    elsif input == "4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return "Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input == "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input == ""
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return "Whatever."
    end
    end
    end
    

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55. Iteration #2
    class Bob
    def hey(input)
    if input == "Tom-ay-to, tom-aaaah-to."
    return "Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input == "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3"
    return "Whatever."
    elsif input == "4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return "Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input == "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input == ""
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return "Whatever."
    end
    end
    end
    

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56. Iteration #2
    class Bob
    def hey(input)
    if input == "Tom-ay-to, tom-aaaah-to."
    return "Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input == "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3"
    return "Whatever."
    elsif input == "4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return "Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input == "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input == ""
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return "Whatever."
    end
    end
    end
    

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57. Iteration #2
    class Bob
    def hey(input)
    case input
    when "Tom-ay-to, tom-aaaah-to."
    "Whatever."
    when "WATCH OUT!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?"
    "Sure."
    when "You are, what, like 15?"
    "Sure."
    when "Let's go make out behind the gym!"
    "Whatever."
    when "It's OK if you don't want to go to the DMV."
    "Whatever."
    when "WHAT THE HELL WERE YOU THINKING?"
    "Whoa, chill out!"
    when "1, 2, 3 GO!"
    "Whoa, chill out!"
    when "1, 2, 3"
    "Whatever."
    when "4?"
    "Sure."
    when "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?\nno"
    "Whatever."
    when "I HATE YOU"
    "Whoa, chill out!"
    when "Ending with ? means a question."
    "Whatever."
    when "Wait! Hang on. Are you going to be OK?"
    "Sure."
    when ""
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    end
    end
    end
    class Bob
    def hey(input)
    if input == "Tom-ay-to, tom-aaaah-to."
    return "Whatever."
    elsif input == "WATCH OUT!"
    return "Whoa, chill out!"
    elsif input == "Does this cryogenic chamber make me look fat?"
    return "Sure."
    elsif input == "You are, what, like 15?"
    return "Sure."
    elsif input == "Let's go make out behind the gym!"
    return "Whatever."
    elsif input == "It's OK if you don't want to go to the DMV."
    return "Whatever."
    elsif input == "WHAT THE HELL WERE YOU THINKING?"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3 GO!"
    return "Whoa, chill out!"
    elsif input == "1, 2, 3"
    return "Whatever."
    elsif input == "4?"
    return "Sure."
    elsif input == "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    return "Whoa, chill out!"
    elsif input == "I HATE YOU"
    return "Whoa, chill out!"
    elsif input == "Ending with ? means a question."
    return "Whatever."
    elsif input == "Wait! Hang on. Are you going to be OK?"
    return "Sure."
    elsif input == ""
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == " "
    return "Fine. Be that way!"
    elsif input == "Does this cryogenic chamber make me look fat?\nno"
    return "Whatever."
    end
    end
    end
    

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58. take-away #2
    

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59. take-away #2
    minimize boilerplate
    

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60. Iteration #3
    class Bob
    def hey(input)
    case input
    when "Tom-ay-to, tom-aaaah-to."
    "Whatever."
    when "WATCH OUT!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?"
    "Sure."
    when "You are, what, like 15?"
    "Sure."
    when "Let's go make out behind the gym!"
    "Whatever."
    when "It's OK if you don't want to go to the DMV."
    "Whatever."
    when "WHAT THE HELL WERE YOU THINKING?"
    "Whoa, chill out!"
    when "1, 2, 3 GO!"
    "Whoa, chill out!"
    when "1, 2, 3"
    "Whatever."
    when "4?"
    

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61. Iteration #3
    case input
    when "Tom-ay-to, tom-aaaah-to."
    "Whatever."
    when "WATCH OUT!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?"
    "Sure."
    when "You are, what, like 15?"
    "Sure."
    when "Let's go make out behind the gym!"
    "Whatever."
    when "It's OK if you don't want to go to the DMV."
    "Whatever."
    when "WHAT THE HELL WERE YOU THINKING?"
    "Whoa, chill out!"
    when "1, 2, 3 GO!"
    "Whoa, chill out!"
    when "1, 2, 3"
    "Whatever."
    when "4?"
    "Sure."
    when "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?\nno"
    "Whatever."
    when "I HATE YOU"
    "Whoa, chill out!"
    when "Ending with ? means a question."
    "Whatever."
    when "Wait! Hang on. Are you going to be OK?"
    "Sure."
    when ""
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    end
    

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62. Iteration #3
    case input
    when "Tom-ay-to, tom-aaaah-to."
    "Whatever."
    when "WATCH OUT!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?"
    "Sure."
    when "You are, what, like 15?"
    "Sure."
    when "Let's go make out behind the gym!"
    "Whatever."
    when "It's OK if you don't want to go to the DMV."
    "Whatever."
    when "WHAT THE HELL WERE YOU THINKING?"
    "Whoa, chill out!"
    when "1, 2, 3 GO!"
    "Whoa, chill out!"
    when "1, 2, 3"
    "Whatever."
    when "4?"
    "Sure."
    when "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?\nno"
    "Whatever."
    when "I HATE YOU"
    "Whoa, chill out!"
    when "Ending with ? means a question."
    "Whatever."
    when "Wait! Hang on. Are you going to be OK?"
    "Sure."
    when ""
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    end
    

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63. Iteration #3
    case input
    when "Tom-ay-to, tom-aaaah-to."
    "Whatever."
    when "WATCH OUT!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?"
    "Sure."
    when "You are, what, like 15?"
    "Sure."
    when "Let's go make out behind the gym!"
    "Whatever."
    when "It's OK if you don't want to go to the DMV."
    "Whatever."
    when "WHAT THE HELL WERE YOU THINKING?"
    "Whoa, chill out!"
    when "1, 2, 3 GO!"
    "Whoa, chill out!"
    when "1, 2, 3"
    "Whatever."
    when "4?"
    "Sure."
    when "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?\nno"
    "Whatever."
    when "I HATE YOU"
    "Whoa, chill out!"
    when "Ending with ? means a question."
    "Whatever."
    when "Wait! Hang on. Are you going to be OK?"
    "Sure."
    when ""
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    end
    

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64. Iteration #3
    case input
    when "Tom-ay-to, tom-aaaah-to."
    "Whatever."
    when "WATCH OUT!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?"
    "Sure."
    when "You are, what, like 15?"
    "Sure."
    when "Let's go make out behind the gym!"
    "Whatever."
    when "It's OK if you don't want to go to the DMV."
    "Whatever."
    when "WHAT THE HELL WERE YOU THINKING?"
    "Whoa, chill out!"
    when "1, 2, 3 GO!"
    "Whoa, chill out!"
    when "1, 2, 3"
    "Whatever."
    when "4?"
    "Sure."
    when "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?\nno"
    "Whatever."
    when "I HATE YOU"
    "Whoa, chill out!"
    when "Ending with ? means a question."
    "Whatever."
    when "Wait! Hang on. Are you going to be OK?"
    "Sure."
    when ""
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    end
    

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65. Iteration #3
    case input
    when "Tom-ay-to, tom-aaaah-to."
    "Whatever."
    when "WATCH OUT!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?"
    "Sure."
    when "You are, what, like 15?"
    "Sure."
    when "Let's go make out behind the gym!"
    "Whatever."
    when "It's OK if you don't want to go to the DMV."
    "Whatever."
    when "WHAT THE HELL WERE YOU THINKING?"
    "Whoa, chill out!"
    when "1, 2, 3 GO!"
    "Whoa, chill out!"
    when "1, 2, 3"
    "Whatever."
    when "4?"
    "Sure."
    when "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?\nno"
    "Whatever."
    when "I HATE YOU"
    "Whoa, chill out!"
    when "Ending with ? means a question."
    "Whatever."
    when "Wait! Hang on. Are you going to be OK?"
    "Sure."
    when ""
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    end
    

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66. Iteration #3
    case input
    when "Tom-ay-to, tom-aaaah-to."
    "Whatever."
    when "WATCH OUT!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?"
    "Sure."
    when "You are, what, like 15?"
    "Sure."
    when "Let's go make out behind the gym!"
    "Whatever."
    when "It's OK if you don't want to go to the DMV."
    "Whatever."
    when "WHAT THE HELL WERE YOU THINKING?"
    "Whoa, chill out!"
    when "1, 2, 3 GO!"
    "Whoa, chill out!"
    when "1, 2, 3"
    "Whatever."
    when "4?"
    "Sure."
    when "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?\nno"
    "Whatever."
    when "I HATE YOU"
    "Whoa, chill out!"
    when "Ending with ? means a question."
    "Whatever."
    when "Wait! Hang on. Are you going to be OK?"
    "Sure."
    when ""
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    when " "
    "Fine. Be that way!"
    end
    

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67. Iteration #3
    class Bob
    def hey(input)
    case input
    when "Tom-ay-to, tom-aaaah-to.", "Let's go make out behind the gym!
    "Whatever."
    when "WATCH OUT!", "WHAT THE HELL WERE YOU THINKING?", "1, 2, 3 GO!
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?", "You are, wha
    "Sure."
    when "", " ", " "
    "Fine. Be that way!"
    end
    end
    end
    

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68. Iteration #3
    ic chamber make me look fat?\nno", "Ending with ? means a question."
    

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69. there
    I fixed it!
    

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70. take-away #3
    

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71. take-away #3
    don’t repeat yourself (DRY)
    

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72. Iteration #4
    class Bob
    def hey(input)
    case input
    when "Tom-ay-to, tom-aaaah-to.", "Let's go make out behind the gym!
    "Whatever."
    when "WATCH OUT!", "WHAT THE HELL WERE YOU THINKING?", "1, 2, 3 GO!
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?", "You are, wha
    "Sure."
    when "", " ", " "
    "Fine. Be that way!"
    end
    end
    end
    

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73. Iteration #4
    class Bob
    def hey(input)
    case input
    when "Tom-ay-to, tom-aaaah-to.",
    "Let's go make out behind the gym!",
    "It's OK if you don't want to go to the DMV.",
    "1, 2, 3",
    "Does this cryogenic chamber make me look fat?\nno",
    "Ending with ? means a question."
    "Whatever."
    when "WATCH OUT!",
    "WHAT THE HELL WERE YOU THINKING?",
    "1, 2, 3 GO!",
    "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!",
    "I HATE YOU"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?",
    "You are, what, like 15?",
    "4?",
    "Wait! Hang on. Are you going to be OK?"
    "Sure."
    when "",
    " ",
    " "
    "Fine. Be that way!"
    end
    end
    end
    

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74. Iteration #4
    "Sure."
    when "",
    " ",
    " "
    "Fine. Be that way!"
    end
    end
    end
    

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75. Iteration #4
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?",
    "You are, what, like 15?",
    "4?",
    "Wait! Hang on. Are you going to be OK?"
    "Sure."
    when "",
    

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76. Iteration #4
    "Whatever."
    when "WATCH OUT!",
    "WHAT THE HELL WERE YOU THINKING?",
    "1, 2, 3 GO!",
    "ZOMG THE %^*@#$(*^ ZOMBIES ARE COMING!!11!!1!",
    "I HATE YOU"
    "Whoa, chill out!"
    when "Does this cryogenic chamber make me look fat?",
    

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77. Iteration #4
    case input
    when "Tom-ay-to, tom-aaaah-to.",
    "Let's go make out behind the gym!",
    "It's OK if you don't want to go to the DMV.",
    "1, 2, 3",
    "Does this cryogenic chamber make me look fat?\nno",
    "Ending with ? means a question."
    "Whatever."
    when "WATCH OUT!",
    

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78. Iteration #5
    class Bob
    def hey(input)
    return "Whoa, chill out!" if input =~ /\A[\dA-Z\s\W]+\z/ and input =~ /[A-Z]/
    return "Sure." if input.split("").last == "?"
    return "Fine. Be that way!" if input.strip == ""
    "Whatever."
    end
    end
    

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79. take-away #4
    

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80. take-away #4
    find the abstraction
    

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81. Iteration #5
    class Bob
    def hey(input)
    return "Whoa, chill out!" if input =~ /\A[\dA-Z\s\W]+\z/ and input =~ /[A-Z]/
    return "Sure." if input.split("").last == "?"
    return "Fine. Be that way!" if input.strip == ""
    "Whatever."
    end
    end
    

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82. Iteration #5
    class Bob
    def hey(input)
    return "Whoa, chill out!" if input =~ /\A[\dA-Z\s\W]+\z/ and input =~ /[A-Z]/
    return "Sure." if input.split("").last == "?"
    return "Fine. Be that way!" if input.strip == ""
    "Whatever."
    end
    end
    

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83. Iteration #5
    input =~ /\A[\dA-Z\s\W]+\z/ and input =~ /[A-Z]/
    

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84. input == input.upcase
    Iteration #5
    

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85. input == input.upcase and input != input.downcase
    Iteration #5
    

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86. Iteration #5
    class Bob
    def hey(input)
    return "Whoa, chill out!" if input == input.upcase and input != input.downcase
    return "Sure." if input.split("").last == "?"
    return "Fine. Be that way!" if input.strip == ""
    "Whatever."
    end
    end
    

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87. Iteration #5
    input.split("").last == "?"
    

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88. Iteration #5
    input.end_with?("?")
    

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89. Iteration #5
    class Bob
    def hey(input)
    return "Whoa, chill out!" if input == input.upcase and input != input.downcase
    return "Sure." if input.end_with?("?")
    return "Fine. Be that way!" if input.strip == ""
    "Whatever."
    end
    end
    

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90. Iteration #5
    input.strip == ""
    

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91. input.strip.empty?
    Iteration #5
    

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92. take-away #5
    

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93. take-away #5
    seek fluency
    

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94. Iteration #6
    class Bob
    def hey(input)
    return "Whoa, chill out!" if input == input.upcase and input != input.downcase
    return "Sure." if input.end_with?("?")
    return "Fine. Be that way!" if input.strip.empty?
    "Whatever."
    end
    end
    

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95. input == input.upcase and input != input.downcase
    So expressive!
    

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96. and
    control flow operator
    

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97. &&
    boolean operator
    

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98. boolean vs control flow
    hungry? && thirsty?
    

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99. rich? && famous?
    boolean vs control flow
    

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100. sing and dance
     boolean vs control flow
     

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101. rise and shine
     boolean vs control flow
     

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102. boolean vs control flow
     if hungry? && thirsty?
     eat and drink and be_merry!
     end
     

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103. Iteration #6
     class Bob
     def hey(input)
     return "Whoa, chill out!" if input == input.upcase and input != input.downcase
     return "Sure." if input.end_with?("?")
     return "Fine. Be that way!" if input.strip.empty?
     "Whatever."
     end
     end
     

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104. Iteration #6
     class Bob
     def hey(input)
     return "Whoa, chill out!" if input == input.upcase && input != input.downcase
     return "Sure." if input.end_with?("?")
     return "Fine. Be that way!" if input.strip.empty?
     "Whatever."
     end
     end
     

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105. take-away #6
     

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106. take-away #6
     familiar isn’t always
     correct
     

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107. Iteration #7
     class Bob
     def hey(input)
     return "Whoa, chill out!" if input == input.upcase && input != input.downcase
     return "Sure." if input.end_with?("?")
     return "Fine. Be that way!" if input.strip.empty?
     "Whatever."
     end
     end
     

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108. Iteration #7
     class Bob
     def hey(input)
     return "Whoa, chill out!" if input == input.upcase && input != input.downcase
     return "Sure." if input.end_with?("?")
     return "Fine. Be that way!" if input.strip.empty?
     "Whatever."
     end
     end
     

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109. Iteration #7
     class Bob
     def hey(input)
     case
     when input == input.upcase && input != input.downcase
     "Whoa, chill out!"
     when input.end_with?("?")
     "Sure."
     when input.strip.empty?
     "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     end
     

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110. take-away #7
     

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111. take-away #7
     shorter is better, unless it
     means something else
     

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112. Iteration #8
     class Bob
     def hey(input)
     case
     when input == input.upcase && input != input.downcase
     "Whoa, chill out!"
     when input.end_with?("?")
     "Sure."
     when input.strip.empty?
     "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     end
     

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113. Iteration #8
     class Bob
     def hey(input)
     @input = input
     case
     when all_caps? then "Whoa, chill out!"
     when question? then "Sure."
     when empty? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     def empty?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def all_caps?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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114. a what-now?
     all_caps?
     question?
     empty?
     

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115. a what-now?
     all_caps?
     question?
     empty?
     ➔ shout?
     

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116. a what-now?
     all_caps?
     question?
     empty?
     ➔ shout?
     ➔ silence?
     

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117. a what-now?
     shout?
     question?
     silence?
     

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118. take-away #8
     

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119. take-away #8
     hide the fiddly details
     

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120. Iteration #9
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     def silence?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def shout?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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121. Iteration #9
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     def silence?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def shout?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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122. Iteration #9
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     def silence?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def shout?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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123. Iteration #9
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     def silence?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def shout?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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124. Iteration #9
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     def silence?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def shout?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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125. Iteration #9
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     def silence?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def shout?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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126. Iteration #9
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     def silence?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def shout?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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127. take-away #9
     

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128. take-away #9
     make the public API coherent
     

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129. Iteration #10
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     def silence?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def shout?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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130. Iteration #10
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     def silence?
     @input.strip.empty?
     end
     def question?
     @input.end_with?("?")
     end
     def shout?
     @input == @input.upcase && @input != @input.downcase
     end
     end
     

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131. Iteration #10
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     attr_reader :input
     def silence?
     input.strip.empty?
     end
     def question?
     input.end_with?("?")
     end
     def shout?
     input == input.upcase && input != input.downcase
     end
     end
     

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132. take-away #10
     

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133. take-away #10
     send a message
     

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134. Iteration #11
     class Bob
     def hey(input)
     @input = input
     case
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     attr_reader :input
     def silence?
     input.strip.empty?
     end
     def question?
     input.end_with?("?")
     end
     def shout?
     input == input.upcase && input != input.downcase
     end
     end
     

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135. confusion ensues
     B A
     

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136. confusion ensues
     B A
     "ARE YOU CRAZY?"
     

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137. "ARE YOU CRAZY?"
     @input
     confusion ensues
     B A
     "ARE YOU CRAZY?"
     

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138. "ARE YOU CRAZY?"
     @input
     confusion ensues
     B A
     "ARE YOU CRAZY?"
     C
     "You’re late."
     

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139. @input
     "You’re late."
     confusion ensues
     B A
     "ARE YOU CRAZY?"
     C
     "You’re late."
     

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140. confusion ensues
     B A
     

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141. @input
     "You’re late."
     confusion ensues
     B A
     

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142. @input
     "You’re late."
     confusion ensues
     "Whatever."
     B A
     

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143. private
     attr_reader :input
     def silence?
     input.strip.empty?
     end
     ...
     Iteration #11
     

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144. private
     attr_reader :input
     def silence?
     input.strip.empty?
     end
     ...
     Iteration #11
     private
     def silence?
     ->(s) { s.strip.empty? }
     end
     ...
     

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145. take-away #11
     

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146. take-away #11
     fleeting state doesn’t
     belong in instance variables
     

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147. Iteration #12
     class Bob
     def hey(input)
     case input
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     def silence?
     ->(s) { s.strip.empty? }
     end
     def question?
     ->(s) { s.end_with?("?") }
     end
     def shout?
     ->(s) { s == s.upcase && s != s.downcase }
     end
     end
     

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148. special case
     case age
     when ->(i) { i < 13 } then "kiddo"
     when ->(i) { i % 25 == 0 } then "quarter"
     when ->(i) { i % 10 == 0 } then "decade"
     end
     

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149. Iteration #12
     class Bob
     def hey(input)
     case input
     when shout? then "Whoa, chill out!"
     when question? then "Sure."
     when silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     def silence?
     ->(s) { s.strip.empty? }
     end
     def question?
     ->(s) { s.end_with?("?") }
     end
     def shout?
     ->(s) { s == s.upcase && s != s.downcase }
     end
     end
     

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150. truth
     def question?
     ->(s) { s.end_with?("?") }
     end
     

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151. Proc.new{ false }
     truth
     

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152. truth
     

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153. !!Proc.new{ false }
     # => true
     truth
     

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154. private
     def silence?
     ->(s) { s.strip.empty? }
     end
     def question?
     ->(s) { s.end_with?("?") }
     end
     def shout?
     ->(s) { s == s.upcase && s != s.downcase }
     end
     Iteration #12
     

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155. private
     def silence?
     ->(s) { s.strip.empty? }
     end
     def question?
     ->(s) { s.end_with?("?") }
     end
     def shout?
     ->(s) { s == s.upcase && s != s.downcase }
     end
     Iteration #12
     private
     def silence?(s)
     s.strip.empty?
     end
     def question?(s)
     s.end_with?("?")
     end
     def shout?(s)
     s == s.upcase && s != s.downcase
     end
     

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156. take-away #12
     

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157. take-away #12
     don’t lie
     

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158. Iteration #13
     class Bob
     def hey(input)
     case
     when shout?(input) then "Whoa, chill out!"
     when question?(input) then "Sure."
     when silence?(input) then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     def silence?(s)
     s.strip.empty?
     end
     def question?(s)
     s.end_with?("?")
     end
     def shout?(s)
     s == s.upcase && s != s.downcase
     end
     end
     

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159. Iteration #13
     class Bob
     def hey(input)
     case
     when shout?(input) then "Whoa, chill out!"
     when question?(input) then "Sure."
     when silence?(input) then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     def silence?(s)
     s.strip.empty?
     end
     def question?(s)
     s.end_with?("?")
     end
     def shout?(s)
     s == s.upcase && s != s.downcase
     end
     end
     

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160. Iteration #13
     class Bob
     def hey(input)
     case
     when shout?(input) then "Whoa, chill out!"
     when question?(input) then "Sure."
     when silence?(input) then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     def silence?(s)
     s.strip.empty?
     end
     def question?(s)
     s.end_with?("?")
     end
     def shout?(s)
     s == s.upcase && s != s.downcase
     end
     end
     

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161. Iteration #13
     class Bob
     def hey(input)
     case
     when shout?(input) then "Whoa, chill out!"
     when question?(input) then "Sure."
     when silence?(input) then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     private
     def silence?(s)
     s.strip.empty?
     end
     def question?(s)
     s.end_with?("?")
     end
     def shout?(s)
     s == s.upcase && s != s.downcase
     end
     end
     

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162. Iteration #13
     class Bob
     def hey(input)
     case
     when input.shout? then "Whoa, chill out!"
     when input.question? then "Sure."
     when input.silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     end
     class String
     def silence?
     strip.empty?
     end
     def question?
     end_with?("?")
     end
     def shout?
     self == upcase && self != downcase
     end
     end
     

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163. take-away #13
     

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164. take-away #13
     make your objects cohesive
     

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165. Iteration #14
     class Bob
     def hey(input)
     case
     when input.shout? then "Whoa, chill out!"
     when input.question? then "Sure."
     when input.silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     end
     class String
     def silence?
     strip.empty?
     end
     def question?
     end_with?("?")
     end
     def shout?
     self == upcase && self != downcase
     end
     end
     

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166. String API
     

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167. String API
     #downcase
     #gsub
     #reverse
     #scan
     #squeeze
     #to_i
     ...
     

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168. String API
     #downcase
     #gsub
     #reverse
     #scan
     #squeeze
     #to_i
     ...
     #question?
     #shout?
     #silence?
     

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169. Iteration #14
     class Bob
     def hey(input)
     case
     when input.shout? then "Whoa, chill out!"
     when input.question? then "Sure."
     when input.silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     end
     class String
     def silence?
     strip.empty?
     end
     def question?
     end_with?("?")
     end
     def shout?
     self == upcase && self != downcase
     end
     end
     

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170. Iteration #14
     class Bob
     def hey(input)
     input = Input.new(input)
     case
     when input.shout? then "Whoa, chill out!"
     when input.question? then "Sure."
     when input.silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     end
     class Input < String
     def silence?
     strip.empty?
     end
     def question?
     end_with?("?")
     end
     def shout?
     self == upcase && self != downcase
     end
     end
     

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171. take-away #14
     

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172. take-away #14
     no, really, make ALL your
     objects cohesive
     

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173. Iteration #15
     class Bob
     def hey(input)
     input = Input.new(input)
     case
     when input.shout? then "Whoa, chill out!"
     when input.question? then "Sure."
     when input.silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     end
     end
     class Input < String
     def silence?
     strip.empty?
     end
     def question?
     end_with?("?")
     end
     def shout?
     self == upcase && self != downcase
     end
     end
     

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174. Input API
     #downcase
     #gsub
     #reverse
     #scan
     #squeeze
     #to_i
     ...
     #question?
     #shout?
     #silence?
     

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175. class DazzlingString < String
     def sparkle
     "**;* #{self} **;**"
     end
     end
     beware!
     

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176. s = DazzlingString.new("unicorn")
     beware!
     

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177. beware!
     

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178. beware!
     s.sparkle
     # => **;* unicorn **;**
     

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179. beware!
     s.sparkle
     # => **;* unicorn **;**
     s.upcase
     # => UNICORN
     

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180. beware!
     s.sparkle
     # => **;* unicorn **;**
     s.upcase
     # => UNICORN
     s << 's'
     # => "unicorns"
     

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181. beware!
     s.sparkle
     # => **;* unicorn **;**
     s.upcase
     # => UNICORN
     s << 's'
     # => "unicorns"
     s.sparkle
     # => **;* unicorns **;**
     

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182. beware!
     

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183. s1 = DazzlingString.new("unicorn")
     beware!
     

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184. s1 = DazzlingString.new("unicorn")
     s2 = DazzlingString.new("rainbow")
     beware!
     

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185. beware!
     

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186. s1.sparkle
     # => **;* unicorn **;**
     s2.sparkle
     # => **;* rainbow **;**
     beware!
     

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187. beware!
     

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188. beware!
     s3 = s1 + s2
     # => "unicornrainbow"
     

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189. beware!
     s3.sparkle
     # => undefined method `sparkle' for
     "unicornrainbow":String (NoMethodError)
     s3 = s1 + s2
     # => "unicornrainbow"
     

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190. Iteration #15
     class Bob
     # ...
     end
     class Input < String
     def silence?
     strip.empty?
     end
     def question?
     end_with?("?")
     end
     def shout?
     self == upcase && self != downcase
     end
     end
     

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191. Iteration #15
     class Bob
     # ...
     end
     class Input
     attr_reader :input
     def initialize(input)
     @input = input
     end
     def silence?
     input.strip.empty?
     end
     def question?
     input.end_with?("?")
     end
     def shout?
     input == input.upcase && input != input.downcase
     end
     end
     

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192. Input API
     #question?
     #shout?
     #silence?
     

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193. Input API
     #question?
     #shout?
     #silence?
     #downcase
     #gsub
     #reverse
     #scan
     #squeeze
     #to_i
     ...
     

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194. take-away #15
     

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195. take-away #15
     no, really, seriously,
     f’reals make your objects
     cohesive
     

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196. Iteration #16
     class Bob
     def hey(input)
     input = Input.new(input)
     case
     # ...
     end
     end
     end
     class Input
     attr_reader :input
     def initialize(input)
     @input = input
     end
     def silence?
     input.strip.empty?
     end
     def question?
     input.end_with?("?")
     end
     def shout?
     input == input.upcase && input != input.downcase
     end
     end
     

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197. Iteration #16
     class Bob
     def hey(input)
     input = Input.new(input)
     case
     # ...
     end
     end
     end
     class Input
     attr_reader :input
     def initialize(input)
     @input = input
     end
     def silence?
     input.strip.empty?
     end
     def question?
     input.end_with?("?")
     end
     def shout?
     input == input.upcase && input != input.downcase
     end
     end
     

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198. naming
     class String
     # ...
     end
     

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199. naming
     class Input
     # ...
     end
     

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200. naming
     class Analyzer
     # ...
     end
     

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201. naming
     class Parser
     # ...
     end
     

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202. naming
     class Classifier
     # ...
     end
     

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203. naming
     class Message
     # ...
     end
     

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204. naming
     class Comment
     # ...
     end
     

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205. naming
     class Statement
     # ...
     end
     

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206. naming
     class Utterance
     # ...
     end
     

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207. naming
     class Confrontation
     # ...
     end
     

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208. naming
     class Drivel
     # ...
     end
     

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209. naming
     class Blathering
     # ...
     end
     

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210. naming
     class Interpretation
     # ...
     end
     

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211. naming
     class Tone
     # ...
     end
     

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212. naming
     class Perception
     # ...
     end
     

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213. point of view
     shout?
     question?
     silence?
     

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214. point of view
     shout?
     question?
     silence?
     ➔ freaking_out?
     ➔ dumb_question?
     ➔ cold_shoulder?
     

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215. naming
     class Remark
     # ...
     end
     

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216. Iteration #16
     class Bob
     def hey(remark)
     remark = Remark.new(remark)
     case
     # ...
     end
     end
     end
     class Remark
     attr_reader :remark
     def initialize(remark)
     @remark = remark
     end
     def silence?
     remark.strip.empty?
     end
     def question?
     remark.end_with?("?")
     end
     def shout?
     remark == remark.upcase && remark != remark.downcase
     end
     end
     

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217. Iteration #16
     class Bob
     def hey(remark)
     remark = Remark.new(remark)
     case
     # ...
     end
     end
     end
     class Remark
     attr_reader :remark
     def initialize(remark)
     @remark = remark
     end
     def silence?
     remark.strip.empty?
     end
     def question?
     remark.end_with?("?")
     end
     def shout?
     remark == remark.upcase && remark != remark.downcase
     end
     end
     

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218. echoes
     remark = Remark.new(remark)
     remark.remark
     

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219. echoes
     host = host.host if host.host?
     

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220. echoes
     member.member.member
     

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221. echoes
     var srcData = data;
     if (data.data && data.data.data) {
     data = data.data.data;
     } else if (data.data) {
     data = data.data;
     }
     if (!data) {
     return;
     }
     

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222. echoes
     remark = Remark.new(remark)
     remark.remark
     

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223. echoes
     remark = Remark.new(text)
     remark.text
     

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224. take-away #16
     

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225. take-away #16
     naming is hard
     

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226. Final Solution
     class Bob
     def hey(text)
     remark = Remark.new(text)
     case
     # ...
     end
     end
     end
     class Remark
     attr_reader :text
     def initialize(text)
     @text = text
     end
     def silence?
     text.strip.empty?
     end
     def question?
     text.end_with?("?")
     end
     def shout?
     text == text.upcase && text != text.downcase
     end
     end
     case
     when remark.shout? then "Whoa, chill out!"
     when remark.question? then "Sure."
     when remark.silence? then "Fine. Be that way!"
     else
     "Whatever."
     end
     

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227. class Bob
     def hey (input )
     if input=="Tom-ay-to, tom-aaaah-to."
     return"Whatever."
     elsif input == "WATCH OUT!"
     return "Whoa, chill out!"
     elsif input == "Does this cryogenic chamber make me look fat?"
     return "Sure."
     elsif input== "You are, what, like 15?"
     return "Sure."
     elsif input == "Let's go make out behind the gym!"
     return "Whatever."
     elsif input == "It's OK if you don't want to go to the DMV."
     return "Whatever."
     Initial Solution
     

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228. practice
     toy problems
     

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229. <3
     thank you
     

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230. credits
     Simple Made Easy
     http://www.infoq.com/presentations/Simple-Made-Easy
     Rich Hickey
     5 elements of Effective Thinking
     Michael Starbird, Edward Burger
     Smalltalk Implementation Patterns
     Kent Beck
     Mark by Mark
     http://vimeo.com/79530470
     Sarah Gray
     

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231. The Devil is in the Details
     Katrina Owen
     @kytrinyx
     http://exercism.io
     

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