Cabbages, Goat, and Wolf In Two Styles!!

[Full text of the talk](https://github.com/jorendorff/talks/blob/master/cabbages/talk.md#wolf-goat-and-cabbage-in-two-styles).

[Video of the talk](https://www.youtube.com/watch?v=KyAHtqi3PUY) (15 minutes, fun!)

Transcript

1. Wolf,
   Goat, &
   Cabbages
   in two styles!!
   

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2. Wolf,
   Goat, &
   Cabbages
   in two styles!!
   Jason Orendorff
   !!Con West 2020
   

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9. X
   

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14. X
    

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15. dagnabbit
    X
    

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16. Wolf,
    Goat, &
    Cabbages
    in two styles!!
    

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17. Wolf,
    Goat, &
    Cabbages
    in two styles!!
    Jason Orendorff
    !!Con West 2020
    

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18. View Slide

19. Book One -
    

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20. Book One - Inform 7
    

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21. Chapter 1 - The River
    The East Riverbank is a room.
    

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22. Chapter 1 - The River
    The East Riverbank is a room. “Here a
    lazy river crosses your path.”
    

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23. Chapter 2 - The Boat
    

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24. Chapter 2 - The Boat
    The boat is an enterable container in the
    East Riverbank. “A little boat is tied to
    the dock.”
    

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25. Chapter 3 - The Treasures
    A treasure is a kind of thing.
    

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26. Chapter 3 - The Treasures
    A treasure is a kind of thing.
    A wolf is in the East Riverbank. […]
    

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27. Chapter 3 - The Treasures
    A treasure is a kind of thing.
    The wolf, the goat, and the cabbages are
    treasures.
    A wolf is in the East Riverbank. […]
    

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29. DIVIDE FORCE BY MASS GIVING ACC.
    Given a book of macabre poetry is in my cart
    When I click "Buy"
    Then I should see "Checkout"
    COBOL (1959)
    Gherkin (2008)
    AppleScript (1993)
    tell application "Preview" to open "manual.pdf"
    activate application "Preview"
    

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30. A treasure is a kind of thing.
    The wolf, the goat, and the cabbages are
    treasures.
    A wolf is in the East Riverbank. […]
    

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31. A treasure is a kind of thing.
    The wolf, the goat, and the cabbages are
    treasures.
    A wolf is in the East Riverbank. […]
    

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32. A treasure is a kind of thing.
    The wolf, the goat, and the cabbages are
    treasures.
    A wolf is in the East Riverbank. […]
    

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33. A treasure is a kind of thing.
    The wolf, the goat, and the cabbages are
    treasures.
    A wolf is in the East Riverbank. […]
    

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34. The boat is an enterable container in the
    East Riverbank.
    

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35. The boat is an enterable container in the
    East Riverbank.
    

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37. East Riverbank
    Here a lazy river crosses your path.
    A boat is tied to a dock nearby.
    The "sheep" you bought at the fair is here.
    Your goat stands nearby, chewing on nothing in particular.
    >
    

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38. East Riverbank
    Here a lazy river crosses your path.
    A boat is tied to a dock nearby.
    The "sheep" you bought at the fair is here.
    Your goat stands nearby, chewing on nothing in particular.
    > drop the cabbages
    Dropped.
    > take goat
    Taken.
    >
    

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39. Instead of taking the boat, say “There’s
    no point carrying a boat around.”
    

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40. >
    

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41. > pick up the river
    

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42. That’s hardly portable.
    > pick up the river
    >
    

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43. That’s hardly portable.
    > pick up the river
    > take the goat
    

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44. You already have that.
    That’s hardly portable.
    > pick up the river
    > take the goat
    >
    

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45. You already have that.
    That’s hardly portable.
    > pick up the river
    > take the goat
    > pick myself up
    

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46. You are always self-possessed.
    You already have that.
    That’s hardly portable.
    > pick up the river
    > take the goat
    > pick myself up
    

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47. Carry out crossing:
    if the wolf and the goat are ashore together:
    say “…”;
    end the story saying “Someone has
    got your goat”;
    else if the goat and the cabbages… :
    …
    otherwise:
    move the boat to the other bank.
    

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49. • The manual is amazing
    

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50. • The manual is amazing
    • “Use the serial comma.”
    

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51. Book Two -
    

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52. Book Two - Alloy
    

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53. class Person {
    loves: set Person
    }
    

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54. class Person {
    loves: set Person
    }
    

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55. sig Person {
    loves: set Person
    }
    

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56. sig Person {
    loves: set Person
    }
    Lin = new Person
    

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57. sig Person {
    loves: set Person
    }
    Lin = new Person
    
    

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59. Sig Person {
    loves: set Person
    }
    run {} for 3
    

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63. Person A loves Person B
    Balin → Dwalin
    Óin → Glóin
    Bombur → Balin
    Bombur → Glóin
    Bombur → Bombur
    

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64. Balin .loves = { Dwalin }
    Óin .loves = { Glóin }
    Bombur.loves = { Balin,
    Glóin,
    Bombur }
    

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66. sig Person {
    loves: set Person
    }
    

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67. sig Person {
    loves: set Person
    }
    Love relates various people
    to various people.
    

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68. sig Person {
    loves: set Person
    }
    Love relates various people
    to various people.
    The verb to love means the love relation.
    

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70. some Bombur.loves
    If Bombur loves anyone…
    Bombur.loves
    everyone loved by Bombur
    Bombur.~loves
    everyone who loves Bombur
    Bombur.loves = Person
    Everyone loves Bombur.
    

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71. Part SR1 - The Physical World Model
    The verb to contain means the containment relation.
    The verb to be in means the reversed containment relation.
    The verb to carry means the carrying relation.
    The verb to hold means the holding relation.
    The verb to wear means the wearing relation.
    

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72. Part SR1 - The Physical World Model
    The verb to contain means the containment relation.
    The verb to be in means the reversed containment relation.
    The verb to carry means the carrying relation.
    The verb to hold means the holding relation.
    The verb to wear means the wearing relation.
    

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73. sig Person {
    loves: set Person
    }
    

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74. sig Object {
    loves: set Object
    }
    

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75. sig Object {
    eats: set Object
    }
    

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76. sig Object {
    eats: set Object
    }
    sig Wolf extends Object {}
    sig Goat extends Object {}
    sig Cabbages extends Object {}
    sig Boat extends Object {}
    

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77. abstract sig Object {
    eats: set Object
    }
    one sig Wolf extends Object {}
    one sig Goat extends Object {}
    one sig Cabbages extends Object {}
    one sig Boat extends Object {}
    

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79. fact foodWeb {
    eats = (Wolf -> Goat)
    + (Goat -> Cabbages)
    }
    

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82. sig Riverbank {}
    

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84. sig Snapshot {
    }
    

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85. sig Snapshot {
    location: Object -> one Riverbank
    }
    

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86. // first, last, prev, next
    open util/ordering[Snapshot]
    sig Snapshot {
    location: Object -> one Riverbank
    }
    

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88. fact twoSidesToEveryRiver {
    #Riverbank = 2
    }
    

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90. fact beginningAndEnd {
    }
    

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91. fact beginningAndEnd {
    }
    one first.location[Object]
    

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92. fact beginningAndEnd {
    }
    one first.location[Object]
    one last.location[Object]
    

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93. fact beginningAndEnd {
    }
    one first.location[Object]
    one last.location[Object]
    first.location[Boat] != last.location[Boat]
    

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96. Why Alloy?
    

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98. https://playfic.com/games/jorendorff/cabbages
    

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