Sugar-Free Ruby

Ruby has a lot of syntax to come to terms with. In an effort to reduce learning overhead we often restrict what we teach by avoiding serious coverage of objects in early lessons. Yet objects are what make Ruby great. Rather than sacrifice Object Oriented Mechanics, Sugar-free ruby uses a minimum of syntactic sugar to reinforce the message-passing objective semantics of Ruby until the pupil understands and then can assimilate new syntactic elements with greater ease. This talk explores the advantages and pitfalls of the technique as well as other ways to teach Ruby.

Transcript

1. Sugar-Free
   Ruby
   A Look at Object-First
   Teaching
   

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2. Who is this guy?
   Steven! Ragnarök
   contact = {
   "GitHub" => "nuclearsandwich",
   "Freenode" => "nuclearsandwich",
   "Email" => "steven@nuclearsandwich.com",
   "WWW" => "www.nuclearsandwich.com",
   "Twitter" => "@nuclearsandwich"
   }
   ''That guy with all the opinions''
   

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3. Teaching
   Programming
   

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4. Why is teaching so
   damn hard?
   

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5. Why is teaching so
   damn hard?
   • It's hard to remember
   learning to program
   

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6. Why is teaching so
   damn hard?
   • It's hard to remember
   learning to program
   • It's hard to share
   knowledge instead of
   guard it
   

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7. Why is teaching so
   damn hard?
   In short: it takes a lot of self
   reflection to teach well.
   

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8. Teaching
   Programming
   It's getting better
   

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9. Kids learn:
   • Game Builder
   • Scratch
   • Python
   • Hackety-Hack / Shoes
   

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10. Programming
    is fun
    

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11. • Workshops for Women
    • Kids Ruby
    • Workshops / Curriculum in
    other languages
    

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12. Programming
    is hard…
    But only this
    hard
    

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13. RailsBridge:
    Workshops for Women
    • Install all the things the
    night before
    • One full day
    • Focus on Ruby, Rails, or
    split based on experience
    

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14. Teaching
    Ruby
    The challenge
    

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15. Why do you want to
    learn Ruby?
    

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16. Why do you want to
    learn Ruby?
    • I hate my job and hear
    programmers make bank
    

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17. Why do you want to
    learn Ruby?
    • I hate my job and hear
    programmers make bank
    • I know how to program but
    not Ruby
    

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18. Why do you want to
    learn Ruby?
    • I hate my job and hear
    programmers make bank
    • I know how to program but
    not Ruby
    • I'm curious about
    programming
    

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19. Disclaimer
    This point onward:
    Open minds only
    

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20. Disclaimer
    Haters, the doors
    are stage left
    

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21. Teaching
    Ruby
    The (Good?) Old
    Fashioned Way
    

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22. Numbers
    5 + 5 #=> 10
    9 / 2 #=> 4
    9.0 / 2 #=> 4.5
    

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23. Strings and Symbols
    'Hello' #=> "Hello"
    :what? #=> :what?
    "Hello, " + "World!"
    #=> "Hello, World!"
    

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24. Boolean Values
    true #=> true
    false #=> false
    20 < 100 #=> true
    true and false #=> false
    true or false #=> true
    

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25. Arrays and Hashes
    [ 1, 2, 3.0, "four" ]
    { :name => "Steven!",
    :age => 24,
    :species => "human" }
    

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26. Variable Assignment
    my_name = "Steven!"
    my_age = 24
    

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27. Variable Access
    # ten years from now
    my_age + 10 #=> 34
    # I hashify myself
    { :name => my_name,
    :age => my_age }
    #=> {:name => "Steven!",
    # :age => 24}
    

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28. Console Output
    puts my_name
    Steven!
    #=> nil
    puts my_age + 10
    34
    #=> nil
    

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29. Conditionals
    if my_name == "Steven!"
    puts "Hello!"
    else
    puts "Who are you?"
    end
    Hello!
    #=> nil
    

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30. Loops
    while my_age < 30 do
    puts "Enjoying my twenties"
    my_age = my_age + 1
    end
    

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31. Methods
    "foo".upcase #=> "FOO"
    

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32. Teaching
    Ruby
    What's wrong with
    this picture?
    

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33. What's wrong with this
    picture?
    Six whole concepts
    come before methods.
    

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34. What's wrong with this
    picture?
    No mention whatsoever
    of classes.
    

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35. What's wrong with this
    picture?
    Why do we cling to this?
    

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36. Ruby is not a computer
    language.
    

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37. Ruby is not a computer
    language.
    So why are we teaching
    it like one?
    

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38. Teaching
    Objects
    Ruby is the computer
    

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39. But Steven!,
    If we try to teach all of that
    and Objects,
    their heads will explode!
    

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40. Everything is an Object
    5 #=> 5
    42.0 #=> 42.0
    "Hello!" #=> "Hello!"
    [1, 2, 3] #=> [1, 2, 3]
    

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41. They Receive Messages
    "six".send :upcase
    #=> "SIX"
    5.send :+, 9
    #=> 14
    17.send :nil?
    #=> false
    

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42. Objects Have (a) Class
    5.send :class
    #=> Fixnum
    4.0.send :class
    #=> Float
    ["he's", "crazy?"].send :class
    #=> Array
    

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43. Teaching
    Objects
    The pen and the scribe
    

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44. Instantiation
    pen = Object.new
    #=> #
    

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45. Method Definition
    def pen.to_s
    "A trusty pen"
    end
    #=> nil
    

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46. Message Sending
    pen.send :to_s
    #=> A trusty pen
    

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47. A Pinch of Sugar
    def pen.to_s
    "A trusty pen"
    end
    pen.to_s
    #=> A trusty pen
    

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48. Errors Are Your Friends
    pen.write "Hi there"
    #=> NoMethodError: undefined
    # method `write' for
    # A trusty pen:Object
    

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49. Use the Kernel, Luke
    def pen.write thing
    Kernel.puts thing
    end
    #=> nil
    

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50. Write Anything!
    pen.write "Hi"
    Hi
    #=> nil
    pen.write pen
    A trusty pen
    #=> nil
    

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51. Feature Request: Color
    pen.ink_color = "Blue"
    #=> NoMethodError: undefined
    # method `ink_color=' for
    # A trusty pen:Object
    def pen.ink_color= color
    @ink_color = color
    end
    #=> nil
    

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52. Showing Our Colors
    def pen.to_s
    "A trusty #{@ink_color} pen"
    end
    pen.ink_color = "purple"
    #=> "purple"
    pen
    #=> "A trusty purple pen"
    

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53. Implicit Receivers
    def pen.sparkly_write thing
    write "*;. #{thing} *;.*"
    end
    pen.sparkly_write pen
    *;. A trusty purple pen *;.*
    

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54. Conditionals Revisited
    def pen.html_write thing
    write if @ink_color
    "#{@ink_color};\">
    #{thing}
    "
    else
    "#{thing}"
    end
    end
    

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55. Teaching
    Ruby
    What have we
    introduced?
    

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56. Time to get classy…
    Scribe = Class.new do
    def initialize pen
    @pen = pen
    @items = Array.new
    end
    def note item
    @items.<< item
    end
    # to be continued
    

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57. …you blockhead
    # in the Scribe class body
    def write_everything
    @items.each do |item|
    @pen.write item
    end
    end
    end
    #=> Scribe
    

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58. Hiring a new scribe
    mielot = Scribe.new pen
    #=> ## @pen=A trusty purple pen>
    mielot.note "Time: #{Time.now}"
    mielot.note "This demo is over"
    mielot.write_everything
    Time: 2012-09-14 11:43:05 -0700
    This demo is over
    

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59. Teaching
    Ruby
    with Objects
    

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60. Teaching
    Objects
    with Ruby
    

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61. Why is this better?
    The object metaphor provides
    a context for everything else
    we learn about Ruby
    

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62. Why is this better?
    We don't bombard them with
    new concepts until just before
    their use
    

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63. Why is this better?
    With a thorough understanding
    of semantics, new things (like
    syntactic sugar) are more
    readily digestible
    

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64. Thanks!
    Behind the Scenes
    X
    E
    L
    A
    TEX/ Beamer
    Pygments / Minted
    

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