Stupid Ruby Tricks

Ruby is awesome. We all love Ruby. And Ruby loves us. We shouldn't abuse Ruby. Well, maybe a little.

Transcript

1. Stupid Ruby Tricks
   Stupid Ruby Tricks
   Mike Moore
   @blowmage
   Mike Moore
   @blowmage
   

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4. Stupid
   Stupid
   

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6. Mike Moore
   Mike Moore
   

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7. Mike Moore
   Mike Moore
   @blowmage
   @blowmage
   

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19. Stupid
    Stupid
    

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20. Hey, can I move to Friday?
    I won’t be prepared in time.
    No problem.
    We’ll move Terence Lee to
    Thursday.
    Sweet!
    

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21. Hey, can I move to Friday?
    I won’t be prepared in time.
    No problem.
    We’ll move Terence Lee to
    Thursday.
    Sweet!
    

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22. Hey, can I move to Friday?
    I won’t be prepared in time.
    No problem.
    We’ll move Terence Lee to
    Thursday.
    Sweet!
    

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23. Hey, can I move to Friday?
    I won’t be prepared in time.
    No problem.
    We’ll move Terence Lee to
    Thursday.
    Sweet!
    

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24. Hey, can I move to Friday?
    I won’t be prepared in time.
    No problem.
    We’ll move Terence Lee to
    Thursday.
    Sweet!
    #FridayHug?!?
    #FridayHug?!?
    

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25. Hey, can I move to Friday?
    I won’t be prepared in time.
    No problem.
    We’ll move Terence Lee to
    Thursday.
    Sweet!
    #FridayHug?!?
    #FridayHug?!?
    

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26. Hey, can I move to Friday?
    I won’t be prepared in time.
    No problem.
    We’ll move Terence Lee to
    Thursday.
    Sweet!
    #FridayHug?!?
    #FridayHug?!?
    

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29. Its full of puns!
    Its full of puns!
    

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30. Stupid
    Stupid
    

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31. Stupid Ruby Trick #1
    File.write/File.read
    Stupid Ruby Trick #1
    File.write/File.read
    

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33. File.open("stupid.txt", "w") do |file|

    file.write("Its all about closures, yo!")

    end

    

    

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34. File.open("stupid.txt", "w") do |file|

    file.write("Its all about closures, yo!")

    end

    

    message = File.open("stupid.txt") do |file|

    file.read

    end

    puts(message)
    

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36. # File.open("stupid.txt", "w") do |file|

    # file.write("Its all about closures, yo!")

    # end
    

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37. # File.open("stupid.txt", "w") do |file|

    # file.write("Its all about closures, yo!")

    # end
    File.write("stupid.txt", "Inline, baby!")

    

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38. # File.open("stupid.txt", "w") do |file|

    # file.write("Its all about closures, yo!")

    # end
    File.write("stupid.txt", "Inline, baby!")

    # message = File.open("stupid.txt") do |file|

    # file.read

    # end

    # puts(message)
    

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39. # File.open("stupid.txt", "w") do |file|

    # file.write("Its all about closures, yo!")

    # end
    File.write("stupid.txt", "Inline, baby!")

    # message = File.open("stupid.txt") do |file|

    # file.read

    # end

    # puts(message)
    puts(File.read("stupid.txt"))
    

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40. Stupid
    Stupid
    

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41. Stupid Ruby Trick #2
    Optional Parenthesis
    Stupid Ruby Trick #2
    Optional Parenthesis
    

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42. File.open("stupid.txt", "w") do |file|

    file.write("Its all about closures, yo!")

    end

    File.write("stupid.txt", "Inline, baby!")

    

    message = File.open("stupid.txt") do |file|

    file.read

    end

    puts(message)

    puts(File.read("stupid.txt"))
    

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43. File.open(”stupid.txt", "w") do |file|

    file.write("Its all about closures, yo!")

    end

    File.write("stupid.txt", "Inline, baby!")

    

    message = File.open("stupid.txt") do |file|

    file.read

    end

    puts(message)

    puts(File.read("stupid.txt"))
    

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44. File.open "stupid.txt", "w" do |file|

    file.write "Its all about closures, yo!"

    end

    File.write "stupid.txt", "Inline, baby!"

    

    message = File.open "stupid.txt" do |file|

    file.read

    end

    puts message

    puts File.read "stupid.txt"
    

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45. Stupid Ruby Advice #1
    Don’t overload lines
    Stupid Ruby Advice #1
    Don’t overload lines
    

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48. Stupid
    Stupid
    

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49. Stupid Ruby Trick #3
    Default Hash Values
    Stupid Ruby Trick #3
    Default Hash Values
    

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51. h = { foo: "FOO", bar: "BAR" }
    

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52. h = { foo: "FOO", bar: "BAR" }
    h[:baz] #=> nil
    

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53. h = { foo: "FOO", bar: "BAR" }
    h[:baz] #=> nil
    h.fetch :baz, "BAZ" #=> “BAZ"
    

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54. h = { foo: "FOO", bar: "BAR" }
    h[:baz] #=> nil
    h.fetch :baz, "BAZ" #=> “BAZ"
    h[:baz] = "TROLLFACE"
    

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55. h = { foo: "FOO", bar: "BAR" }
    h[:baz] #=> nil
    h.fetch :baz, "BAZ" #=> “BAZ"
    h[:baz] = "TROLLFACE"
    h.fetch :baz, "BAZ" #=> "TROLLFACE"
    

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57. hash_list = Hash.new []
    

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58. hash_list = Hash.new []
    hash_list[:nope]
    

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59. hash_list = Hash.new []
    hash_list[:nope]
    hash_list[:nope] << :x
    

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60. hash_list = Hash.new []
    hash_list[:nope]
    hash_list[:nope] << :x
    hash_list[:nope] << :y
    

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61. hash_list = Hash.new []
    hash_list[:nope]
    hash_list[:nope] << :x
    hash_list[:nope] << :y
    hash_list[:nope] << :z
    

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62. hash_list = Hash.new []
    hash_list[:nope]
    hash_list[:nope] << :x
    hash_list[:nope] << :y
    hash_list[:nope] << :z
    hash_list[:nope] #=> [:x, :y, :z]
    

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63. hash_list = Hash.new []
    hash_list[:nope]
    hash_list[:nope] << :x
    hash_list[:nope] << :y
    hash_list[:nope] << :z
    hash_list[:nope] #=> [:x, :y, :z]
    hash_list[:not_even] #=> [:x, :y, :z]
    

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64. hash_list = Hash.new Array.new

    hash_list[:nope]

    hash_list[:nope] << :x

    hash_list[:nope] << :y

    hash_list[:nope] << :z

    hash_list[:nope] #=> [:x, :y, :z]

    hash_list[:not_even] #=> [:x, :y, :z]
    

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66. default #=> "default_value"

    h = Hash.new default

    

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67. default #=> "default_value"

    h = Hash.new default

    h[:nope] #=> "default_value"

    

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68. default #=> "default_value"

    h = Hash.new default

    h[:nope] #=> "default_value"

    default.upcase!

    

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69. default #=> "default_value"

    h = Hash.new default

    h[:nope] #=> "default_value"

    default.upcase!

    h[:nope] #=> "DEFAULT_VALUE"
    

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71. hash_list = Hash.new { |h, k| h[k] = [] }
    

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72. hash_list = Hash.new { |h, k| h[k] = [] }
    hash_list[:nope]
    

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73. hash_list = Hash.new { |h, k| h[k] = [] }
    hash_list[:nope]
    hash_list[:nope] << :x

    hash_list[:nope] << :y

    hash_list[:nope] << :z
    

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74. hash_list = Hash.new { |h, k| h[k] = [] }
    hash_list[:nope]
    hash_list[:nope] << :x

    hash_list[:nope] << :y

    hash_list[:nope] << :z
    hash_list[:nope] #=> [:x, :y, :z]
    

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75. hash_list = Hash.new { |h, k| h[k] = [] }
    hash_list[:nope]
    hash_list[:nope] << :x

    hash_list[:nope] << :y

    hash_list[:nope] << :z
    hash_list[:nope] #=> [:x, :y, :z]
    hash_list[:not_even] #=> []
    

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77. hash_recurs = Hash.new { |h, k| h[k] = {} }
    

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78. hash_recurs = Hash.new { |h, k| h[k] = {} }
    hash_recurs #=> {}
    

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79. hash_recurs = Hash.new { |h, k| h[k] = {} }
    hash_recurs #=> {}
    hash_recurs[:x] #=> {}
    

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80. hash_recurs = Hash.new { |h, k| h[k] = {} }
    hash_recurs #=> {}
    hash_recurs[:x] #=> {}
    hash_recurs[:x][:y] #=> nil
    

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81. hash_recurs = Hash.new { |h, k| h[k] = {} }
    hash_recurs #=> {}
    hash_recurs[:x] #=> {}
    hash_recurs[:x][:y] #=> nil
    hash_recurs[:x][:y][:z]

    #=> NoMethodError: undefined method `[]'
    for nil:NilClass
    

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83. hash_recurs = Hash.new do |h, k|

    h[k] = Hash.new &h.default_proc

    end
    

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84. hash_recurs = Hash.new do |h, k|

    h[k] = Hash.new &h.default_proc

    end
    hash_recurs[:x] #=> {}
    

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85. hash_recurs = Hash.new do |h, k|

    h[k] = Hash.new &h.default_proc

    end
    hash_recurs[:x] #=> {}
    hash_recurs[:x][:y] #=> {}
    

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86. hash_recurs = Hash.new do |h, k|

    h[k] = Hash.new &h.default_proc

    end
    hash_recurs[:x] #=> {}
    hash_recurs[:x][:y] #=> {}
    hash_recurs[:x][:y][:z] #=> {}
    

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87. hash_recurs = Hash.new do |h, k|

    h[k] = Hash.new &h.default_proc

    end
    hash_recurs[:x] #=> {}
    hash_recurs[:x][:y] #=> {}
    hash_recurs[:x][:y][:z] #=> {}
    hash_recurs #=> {:x=>{:y=>{:z=>{}}}}
    

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89. frankenstein = Hash.new { |h, k| h[k] = [] }
    

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90. frankenstein = Hash.new { |h, k| h[k] = [] }
    frankenstein[:nope] << :x << :y << :z
    

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91. frankenstein = Hash.new { |h, k| h[k] = [] }
    frankenstein[:nope] << :x << :y << :z
    frankenstein[:nope] #=> [:x, :y, :z]
    

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92. frankenstein = Hash.new { |h, k| h[k] = [] }
    frankenstein[:nope] << :x << :y << :z
    frankenstein[:nope] #=> [:x, :y, :z]
    frankenstein[:not_even] #=> []
    

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93. frankenstein = Hash.new { |h, k| h[k] = [] }
    frankenstein[:nope] << :x << :y << :z
    frankenstein[:nope] #=> [:x, :y, :z]
    frankenstein[:not_even] #=> []
    frankenstein #=> {:nope=>[:x, :y, :z], :not_even=>[]}
    

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94. frankenstein = Hash.new { |h, k| h[k] = [] }
    frankenstein[:nope] << :x << :y << :z
    frankenstein[:nope] #=> [:x, :y, :z]
    frankenstein[:not_even] #=> []
    frankenstein #=> {:nope=>[:x, :y, :z], :not_even=>[]}
    frankenstein.default_proc = ->(h, k) do

    h[k] = Hash.new &h.default_proc

    end
    

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95. frankenstein = Hash.new { |h, k| h[k] = [] }
    frankenstein[:nope] << :x << :y << :z
    frankenstein[:nope] #=> [:x, :y, :z]
    frankenstein[:not_even] #=> []
    frankenstein #=> {:nope=>[:x, :y, :z], :not_even=>[]}
    frankenstein.default_proc = ->(h, k) do

    h[k] = Hash.new &h.default_proc

    end
    frankenstein[:x][:y][:z] #=> {}
    

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96. frankenstein = Hash.new { |h, k| h[k] = [] }
    frankenstein[:nope] << :x << :y << :z
    frankenstein[:nope] #=> [:x, :y, :z]
    frankenstein[:not_even] #=> []
    frankenstein #=> {:nope=>[:x, :y, :z], :not_even=>[]}
    frankenstein.default_proc = ->(h, k) do

    h[k] = Hash.new &h.default_proc

    end
    frankenstein[:x][:y][:z] #=> {}
    frankenstein

    #=> {:nope=>[:x, :y, :z], :not_even=>[],

    :x=>{:y=>{:z=>{}}}}
    

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98. Stupid
    Stupid
    

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99. Stupid Ruby Trick #4
    include vs. prepend and super
    Stupid Ruby Trick #4
    include vs. prepend and super
    

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100. module Foo

     def do_the_thing

     puts "Foo!"

     end

     end

     class Me

     include Foo

     

     def do_the_thing

     puts "Me!"

     end

     end

     

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101. module Foo

     def do_the_thing

     puts "Foo!"

     end

     end

     class Me

     include Foo

     

     def do_the_thing

     puts "Me!"

     end

     end

     Me.new.do_the_thing
     

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102. module Foo

     def do_the_thing

     puts "Foo!"

     end

     end

     class Me

     include Foo

     

     def do_the_thing

     puts "Me!"

     end

     end

     Me.new.do_the_thing
     "Me!"
     

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103. module Foo

     def do_the_thing

     puts "Foo!"

     end

     end

     class Me

     include Foo

     

     def do_the_thing

     puts "Me!"

     super

     end

     end
     

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104. module Foo

     def do_the_thing

     puts "Foo!"

     end

     end

     class Me

     include Foo

     

     def do_the_thing

     puts "Me!"

     super

     end

     end
     Me.new.do_the_thing
     

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105. module Foo

     def do_the_thing

     puts "Foo!"

     end

     end

     class Me

     include Foo

     

     def do_the_thing

     puts "Me!"

     super

     end

     end
     Me.new.do_the_thing
     "Me!"

     "Foo!"
     

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106. module Foo

     def do_the_thing

     puts "Foo!"

     end

     end

     

     class Me

     prepend Foo

     

     def do_the_thing

     puts "Me!"

     super

     end

     end
     

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107. module Foo

     def do_the_thing

     puts "Foo!"

     end

     end

     

     class Me

     prepend Foo

     

     def do_the_thing

     puts "Me!"

     super

     end

     end
     Me.new.do_the_thing
     

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108. module Foo

     def do_the_thing

     puts "Foo!"

     end

     end

     

     class Me

     prepend Foo

     

     def do_the_thing

     puts "Me!"

     super

     end

     end
     Me.new.do_the_thing
     "Foo!"
     

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109. module Foo

     def do_the_thing

     puts "Foo!"

     super

     end

     end

     

     class Me

     prepend Foo

     

     def do_the_thing

     puts "Me!"

     super

     end

     end
     

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110. module Foo

     def do_the_thing

     puts "Foo!"

     super

     end

     end

     

     class Me

     prepend Foo

     

     def do_the_thing

     puts "Me!"

     super

     end

     end
     Me.new.do_the_thing
     

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111. module Foo

     def do_the_thing

     puts "Foo!"

     super

     end

     end

     

     class Me

     prepend Foo

     

     def do_the_thing

     puts "Me!"

     super

     end

     end
     Me.new.do_the_thing
     "Foo!"

     "Me!"

     #=> NoMethodError: super: no
     superclass method `do_the_thing'
     for #
     

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112. module Foo

     def do_the_thing

     puts "Foo!"

     super if defined? super

     end

     end

     

     class Me

     prepend Foo

     

     def do_the_thing

     puts "Me!"

     super if defined? super

     end

     end
     

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113. module Foo

     def do_the_thing

     puts "Foo!"

     super if defined? super

     end

     end

     

     class Me

     prepend Foo

     

     def do_the_thing

     puts "Me!"

     super if defined? super

     end

     end
     Me.new.do_the_thing
     

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114. module Foo

     def do_the_thing

     puts "Foo!"

     super if defined? super

     end

     end

     

     class Me

     prepend Foo

     

     def do_the_thing

     puts "Me!"

     super if defined? super

     end

     end
     Me.new.do_the_thing
     "Foo!"

     "Me!"
     

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115. module Foo

     def do_the_thing

     puts "Foo!"

     super if defined? super

     end

     end

     

     class Me

     include Foo

     

     def do_the_thing

     puts "Me!"

     super if defined? super

     end

     end
     

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116. module Foo

     def do_the_thing

     puts "Foo!"

     super if defined? super

     end

     end

     

     class Me

     include Foo

     

     def do_the_thing

     puts "Me!"

     super if defined? super

     end

     end
     Me.new.do_the_thing
     

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117. module Foo

     def do_the_thing

     puts "Foo!"

     super if defined? super

     end

     end

     

     class Me

     include Foo

     

     def do_the_thing

     puts "Me!"

     super if defined? super

     end

     end
     Me.new.do_the_thing
     "Me!"

     "Foo!"
     

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118. $ say "it all"
     

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119. View Slide

120. Stupid
     Stupid
     

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121. View Slide

122. View Slide

123. Stupid Ruby Trick #5
     DATA and __END__
     Stupid Ruby Trick #5
     DATA and __END__
     

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124. class Countries

     COUNTRIES = ["Afghanistan", “Aland Islands",

     "Andorra", “Angola", "Anguilla",

     "Antarctica", "Antigua And Barbuda",

     "Argentina", "Armenia", "Aruba",

     "Australia", “Austria", …]

     end
     

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125. class Countries

     COUNTRIES = DATA.read.split

     end

     

     __END__

     Afghanistan,Aland Islands,Albania,Algeria,…
     

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126. require "yaml"

     

     class Countries

     COUNTRIES = YAML.load DATA.read

     end

     

     __END__

     ---

     - name: Afghanistan

     code: AF

     - name: "Åland Islands"

     code: AX …
     

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127. View Slide

128. View Slide

129. Stupid
     Stupid
     

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130. Stupid Ruby Trick #6
     pstore
     Stupid Ruby Trick #6
     pstore
     

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131. require "pstore"

     

     db = PStore.new("stupid.pstore")

     

     db.transaction do

     db["useful info"] = 2

     db["puns"] = 999999999

     end

     

     db.transaction true do

     puts "This session has had #{db["useful info"]} tips."

     puts "So far we have had #{db["puns"]} puns."

     end
     

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132. # Update the data

     db.transaction do

     db["useful info"] +=1

     db["puns"] = Float::INFINITY

     end

     

     db.transaction true do

     puts "This session has had #{db["useful info"]} tips."

     puts "So far we have had #{db["puns"]} puns."

     end
     

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133. View Slide

134. require "pstore"

     require "ostruct"

     

     db = PStore.new("stupid.pstore")

     

     local_obj = OpenStruct.new name: "Mike Moore",

     username: "blowmage"

     

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135. require "pstore"

     require "ostruct"

     

     db = PStore.new("stupid.pstore")

     

     local_obj = OpenStruct.new name: "Mike Moore",

     username: "blowmage"

     db.transaction do

     db["user"] = local_obj

     end

     

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136. require "pstore"

     require "ostruct"

     

     db = PStore.new("stupid.pstore")

     

     local_obj = OpenStruct.new name: "Mike Moore",

     username: "blowmage"

     db.transaction do

     db["user"] = local_obj

     end

     from_db = nil

     db.transaction do

     from_db = db["user"]

     end
     

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137. View Slide

138. class User

     attr_accessor :name, :username

     end
     

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139. class User

     attr_accessor :name, :username

     end
     

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140. class User

     attr_accessor :name, :username

     end
     require "pstore"

     

     db = PStore.new("stupid.pstore")

     

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141. class User

     attr_accessor :name, :username

     end
     require "pstore"

     

     db = PStore.new("stupid.pstore")

     local_obj = User.new.tap do |user|

     user.name = "Mike Moore"

     user.username = "blowmage"

     end

     

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142. class User

     attr_accessor :name, :username

     end
     require "pstore"

     

     db = PStore.new("stupid.pstore")

     local_obj = User.new.tap do |user|

     user.name = "Mike Moore"

     user.username = "blowmage"

     end

     db.transaction { db["user"] = local_obj }

     

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143. class User

     attr_accessor :name, :username

     end
     require "pstore"

     

     db = PStore.new("stupid.pstore")

     local_obj = User.new.tap do |user|

     user.name = "Mike Moore"

     user.username = "blowmage"

     end

     db.transaction { db["user"] = local_obj }

     from_db = db.transaction { db["user"] }
     

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144. require "yaml/store"

     

     class User

     attr_accessor :name, :username

     end

     

     db = YAML::Store.new("stupid.yml")

     

     local_obj = User.new.tap do |user|

     user.name = "Mike Moore"

     user.username = "blowmage"

     end

     

     db.transaction { db["user"] = local_obj }

     

     from_db = db.transaction { db["user"] }
     

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145. View Slide

146. View Slide

147. Stupid
     Stupid
     

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148. View Slide

149. Better Sources
     • http://confreaks.tv/videos/railsconf2012-ten-things-you-didn-t-
     know-rails-could-do
     • http://www.thagomizer.com/blog/2015/02/20/the-cool_shit-
     file.html
     

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150. Thank you!
     Thank you!
     

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151. Thank you!
     Thank you!
     

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