Ruby Function Composition

Ruby can elegantly blend both Functional Programming and Object Oriented design patterns together with minimal effort. In this talk, I'll combine both of these design patterns by briefly walking you through the fundamentals of functional composition, appling monads, and finally wrapping all of this up in a nice transactional pipeline object composed of multiple -- and fault tolerant -- operations for building more robust architectures. You'll learn a lot and walk away with new patterns to apply to your own code base.

Transcript

1. Ruby Function Composition
   Presented by Brooke Kuhlmann
   g(f(x))
   f(x)
   x
   A B C
   f g
   

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2. Overview
   

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3. Ruby
   Overview
   Fundamentals
   

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4. Dry Monads
   Ruby
   Overview
   Fundamentals
   Railway Pattern
   

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5. Transactable
   Dry Monads
   Ruby
   Overview
   Fundamentals
   Railway Pattern
   Fault tolerent pipelines
   

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6. What?
   

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7. https://en.wikipedia.org/wiki/Function_composition_(computer_science)
   What
   

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8. https://en.wikipedia.org/wiki/Function_composition_(computer_science)
   What
   "[F]unction composition is an act or mechanism to combine simple
   functions to build more complicated ones. Like the usual
   composition of functions in mathematics, the result of each
   function is passed as the argument of the next, and the result of
   the last one is the result of the whole."
   -- Wikipedia
   

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9. https://www.alchemists.io/articles/ruby_function_composition
   What
   

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10. https://www.alchemists.io/articles/ruby_function_composition
    What
    

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11. https://www.alchemists.io/articles/ruby_function_composition
    What
    

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12. https://www.alchemists.io/articles/ruby_function_composition
    What
    

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13. https://www.alchemists.io/articles/ruby_function_composition
    What
    1
    

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14. https://www.alchemists.io/articles/ruby_function_composition
    What
    1
    2
    

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15. https://www.alchemists.io/articles/ruby_function_composition
    What
    1
    2 3
    

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16. https://www.alchemists.io/articles/ruby_function_composition
    What
    

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17. https://www.alchemists.io/articles/ruby_function_composition
    What
    (5 + 3) * 3 = 24
    

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18. History
    

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19. History
    https://www.alchemists.io/articles/ruby_function_composition
    

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20. History
    Ruby 2.6.0
    https://www.alchemists.io/articles/ruby_function_composition
    

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21. History
    Ruby 2.6.0
    Methods: #>> #<<
    https://www.alchemists.io/articles/ruby_function_composition
    (forward composition) (backward composition)
    

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22. History
    Ruby 2.6.0
    Methods:
    Proc Method
    #>> #<<
    Objects:
    https://www.alchemists.io/articles/ruby_function_composition
    (forward composition) (backward composition)
    

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23. Fundamentals
    

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24. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    

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25. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    Procs Lambdas Methods Classes
    

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26. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    

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27. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m m m m m
    m
    m m m m m m m
    3|
    | | | | | | | | | |
    Procs
    

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28. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m m m m m
    m
    m m m m m m m
    3|
    | | | | | | | | | |
    Procs
    

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29. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m m m m m
    m
    m m m m m m m
    3|
    | | | | | | | | | |
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # #
    Procs
    

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30. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m m m m m
    m
    m m m m m m m
    3|
    | | | | | | | | | |
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # #
    m
    m m m m m m m m m m m m m m m m m
    # #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    Procs
    

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31. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m m m m m
    m
    m m m m m m m
    3|
    | | | | | | | | | |
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # #
    m
    m m m m m m m m m m m m m m m m m
    # #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    m
    m m m m m m m m m m m m m m
    3 #
    #
    Procs
    

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32. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    multiplier = proc { |number, by = 3| number * by }
    multiplier.class # Proc
    multiplier.inspect # #
    multiplier.call 3 # 9
    multiplier.call 3, 10 # 30
    Procs
    

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33. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    

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34. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m
    m
    m m m m m m m
    3
    Lam
    bdas
    

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35. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m
    m
    m m m m m m m
    3
    Lam
    bdas
    

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36. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m
    m
    m m m m m m m
    3
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # #
    Lam
    bdas
    

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37. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m
    m
    m m m m m m m
    3
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    Lam
    bdas
    

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38. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m
    m
    m m m m m m m
    3
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    Lam
    bdas
    

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39. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    m
    m m m m m m m m m m m m m m
    m
    m m m m m m m
    3
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    m
    m m m m m m m m m m m m m m
    3 #
    #
    Lam
    bdas
    

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40. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    multiplier = -> number, by = 3 { number * by }
    multiplier.class # Proc
    multiplier.inspect # "#"
    multiplier.call 3 # 9
    multiplier.call 3, 10 # 30
    Lam
    bdas
    

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41. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    

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42. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    M
    ethods
    

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43. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    M
    ethods
    

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44. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    M
    ethods
    

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45. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    m
    m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m
    m
    m m m m m m m
    M
    ethods
    

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46. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    m
    m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m
    m
    m m m m m m m
    M
    ethods
    

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47. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    m
    m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m
    m
    m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # #
    M
    ethods
    

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48. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    m
    m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m
    m
    m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    M
    ethods
    

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49. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    m
    m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m
    m
    m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    M
    ethods
    

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50. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    m
    m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m
    m
    m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    m
    m m m m m m m m m m m m m m
    3 #
    #
    M
    ethods
    

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51. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    m
    m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m
    m
    m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    m
    m m m m m m m m m m m m m m
    3 #
    #
    m
    m m m m m m m m m m m m m m
    3, 1
    1
    #
    # #
    M
    ethods
    

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52. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    m
    m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m
    m
    m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    m
    m m m m m m m m m m m m m m
    3 #
    #
    m
    m m m m m m m m m m m m m m
    3, 1
    1
    #
    # #
    f
    f f f f f f f f f f f f f f f f f f f f f f f f f f
    M
    ethods
    

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53. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    C
    C C C C C C C C C C C C C C C C C C C C
    d
    d d d d d d
    .m
    m m m m m m m
    (
    ( ( ( ( ( ( ( ( ( (
    3)
    ) ) ) ) ) ) ) ) ) ) )
    m
    m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m
    m
    m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    m
    m m m m m m m m m m m m m m
    3 #
    #
    m
    m m m m m m m m m m m m m m
    3, 1
    1
    #
    # #
    f
    f f f f f f f f f f f f f f f f f f f f f f f f f f
    f
    f f f f f f f f
    c
    c c c c
    #
    # # # #
    M
    ethods
    

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54. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    Calculate = Module.new { def self.multiply(number, by = 3) = number * by }
    multiplier = Calculate.method :multiply
    multiplier.class # Method
    multiplier.inspect # "#"
    multiplier.call 3 # 9
    multiplier.call 3, 10 # 30
    function = multiplier.to_proc
    function.class # Proc
    function.inspect # #
    M
    ethods
    

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55. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    Calculate = Module.new { def self.multiply(number, by = 3) = number * by }
    multiplier = Calculate.method :multiply
    multiplier.class # Method
    multiplier.inspect # "#"
    multiplier.call 3 # 9
    multiplier.call 3, 10 # 30
    function = multiplier.to_proc
    function.class # Proc
    function.inspect # #
    M
    ethods
    

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56. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    

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57. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    c
    c c c c
    d
    d d
    3
    @
    @ @
    e
    e e
    d
    d d
    c
    c c c
    (
    ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( (
    p
    p p p p p p
    e
    e e
    C
    lasses
    

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58. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    c
    c c c c
    d
    d d
    3
    @
    @ @
    e
    e e
    d
    d d
    c
    c c c
    (
    ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( (
    p
    p p p p p p
    e
    e e
    C
    lasses
    

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59. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    c
    c c c c
    d
    d d
    3
    @
    @ @
    e
    e e
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    d d
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    p
    p p p p p p
    e
    e e
    C
    lasses
    

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60. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    c
    c c c c
    d
    d d
    3
    @
    @ @
    e
    e e
    d
    d d
    c
    c c c
    (
    ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( (
    p
    p p p p p p
    e
    e e
    m
    m m m m m m m m m m m m m m m m m m m m m m m m
    C
    lasses
    

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61. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    c
    c c c c
    d
    d d
    3
    @
    @ @
    e
    e e
    d
    d d
    c
    c c c
    (
    ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( (
    p
    p p p p p p
    e
    e e
    m
    m m m m m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # # # # # #
    C
    lasses
    

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62. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    c
    c c c c
    d
    d d
    3
    @
    @ @
    e
    e e
    d
    d d
    c
    c c c
    (
    ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( (
    p
    p p p p p p
    e
    e e
    m
    m m m m m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # # # # # #
    m
    m m m m m m m m m m m m m m m m m
    #
    #
    #
    # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
    C
    lasses
    

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63. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    c
    c c c c
    d
    d d
    3
    @
    @ @
    e
    e e
    d
    d d
    c
    c c c
    (
    ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( ( (
    p
    p p p p p p
    e
    e e
    m
    m m m m m m m m m m m m m m m m m m m m m m m m
    m
    m m m m m m m m m m
    c
    c c c c
    #
    # # # # # # # # # #
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    m m m m m m m m m m m m m m m m m
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    m
    m m m m m m m m m m m m m m
    3 #
    #
    C
    lasses
    

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64. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    class Multiplier
    def initialize by = 3
    @by = by
    end
    def call(number) = number * by
    private
    attr_reader :by
    end
    multiplier = Multiplier.new
    multiplier.class # Multiplier
    multiplier.inspect # "#"
    multiplier.call 3 # 9
    Multiplier.new(10).call 3 # 30
    C
    lasses
    

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65. Fundamentals
    https://www.alchemists.io/articles/ruby_function_composition
    class Multiplier
    def initialize by = 3
    @by = by
    end
    def call(number) = number * by
    private
    attr_reader :by
    end
    multiplier = Multiplier.new
    multiplier.class # Multiplier
    multiplier.inspect # "#"
    multiplier.call 3 # 9
    Multiplier.new(10).call 3 # 30
    C
    lasses
    

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66. View Slide

67. Composition
    

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68. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    Procs Lambdas Methods Classes
    >> >> >>
    

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69. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    Procs Lambdas Methods Classes
    >> >> >>
    

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70. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    Procs
    Lambdas Methods
    Classes
    >> >> >>
    

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71. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    Procs
    Lambdas
    Methods Classes
    >> >> >>
    

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72. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    

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73. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    © Wallpaper Cave
    Some assembly required.
    

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74. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    

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75. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    module Composable
    def >>(other) = method(:call) >> other
    def <<(other) = method(:call) << other
    def call = fail NotImplementedError, "`#{self.class.name}##{__method__}` must be implemented."
    end
    

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76. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    module Composable
    def >>(other) = method(:call) >> other
    def <<(other) = method(:call) << other
    def call = fail NotImplementedError, "`#{self.class.name}##{__method__}` must be implemented."
    end
    

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77. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    module Composable
    def >>(other) = method(:call) >> other
    def <<(other) = method(:call) << other
    def call = fail NotImplementedError, "`#{self.class.name}##{__method__}` must be implemented."
    end
    Transactable
    

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78. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    Class
    

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79. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    class Divider
    include Composable
    def initialize by = 3
    @by = by
    end
    def call(number) = number / by
    private
    attr_reader :by
    end
    Class
    

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80. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    class Divider
    include Composable
    def initialize by = 3
    @by = by
    end
    def call(number) = number / by
    private
    attr_reader :by
    end
    Class
    

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81. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    Method
    

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82. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    module Calculate
    def self.multiply(number, by = 3) = number * by
    end
    Method
    

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83. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    

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84. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    adder = proc { |number, by = 3| number + by }
    subtracter = -> number, by = 3 { number - by }
    divider = Divider.new
    multiplier = Calculate.method :multiply
    

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85. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    adder = proc { |number, by = 3| number + by }
    subtracter = -> number, by = 3 { number - by }
    divider = Divider.new
    multiplier = Calculate.method :multiply
    Proc
    

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86. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    adder = proc { |number, by = 3| number + by }
    subtracter = -> number, by = 3 { number - by }
    divider = Divider.new
    multiplier = Calculate.method :multiply
    Proc
    Lambda
    

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87. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    adder = proc { |number, by = 3| number + by }
    subtracter = -> number, by = 3 { number - by }
    divider = Divider.new
    multiplier = Calculate.method :multiply
    Proc
    Lambda
    Class
    

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88. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    adder = proc { |number, by = 3| number + by }
    subtracter = -> number, by = 3 { number - by }
    divider = Divider.new
    multiplier = Calculate.method :multiply
    Proc
    Lambda
    Class
    Method
    

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89. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    adder = proc { |number, by = 3| number + by }
    subtracter = -> number, by = 3 { number - by }
    divider = Divider.new
    multiplier = Calculate.method :multiply
    Proc
    Lambda
    Class
    Method
    Composable
    

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90. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    multiplier
    
    
    (method)
    subtractor
    
    
    (lambda)
    adder
    
    
    (proc)
    divider
    
    
    (class)
    >> >> >>
    

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91. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    multiplier
    
    
    (method)
    subtractor
    
    
    (lambda)
    adder
    
    
    (proc)
    divider
    
    
    (class)
    >> >> >>
    

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92. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    

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93. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    (adder >> multiplier).call 10 # 39
    (multiplier << adder).call 10 # 39
    

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94. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    (adder >> multiplier).call 10 # 39
    (multiplier << adder).call 10 # 39
    Forward composition
    

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95. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    (adder >> multiplier).call 10 # 39
    (multiplier << adder).call 10 # 39
    Forward composition
    Backward composition
    

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96. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    (adder >> multiplier).call 10 # 39
    (multiplier << adder).call 10 # 39
    

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97. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    (adder >> multiplier).call 10 # 39
    (multiplier << adder).call 10 # 39
    

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98. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    (adder >> multiplier).call 10 # 39
    (multiplier << adder).call 10 # 39
    (10 + 3) * 3 = 39
    

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99. Composition
    https://www.alchemists.io/articles/ruby_function_composition
    (adder >> multiplier).call 10 # 39
    (multiplier << adder).call 10 # 39
    (10 + 3) * 3 = 39
    📖
    

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100. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier).call 10 # 39
     (multiplier << adder).call 10 # 39
     (10 + 3) * 3 = 39
     📖
     1
     

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101. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier).call 10 # 39
     (multiplier << adder).call 10 # 39
     (10 + 3) * 3 = 39
     📖
     1
     

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102. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier).call 10 # 39
     (multiplier << adder).call 10 # 39
     (10 + 3) * 3 = 39
     📖
     1
     

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103. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier).call 10 # 39
     (multiplier << adder).call 10 # 39
     (10 + 3) * 3 = 39
     📖
     1
     2
     

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104. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier).call 10 # 39
     (multiplier << adder).call 10 # 39
     (10 + 3) * 3 = 39
     📖
     1
     2
     

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105. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier).call 10 # 39
     (multiplier << adder).call 10 # 39
     

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106. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier).call 10 # 39
     (multiplier << adder).call 10 # 39
     ⭐
     

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107. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     

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108. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier >> subtracter >> divider).call 10 # 12
     (divider << subtracter << multiplier << adder).call 10 # 12
     

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109. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier >> subtracter >> divider).call 10 # 12
     (divider << subtracter << multiplier << adder).call 10 # 12
     (((10 + 3) * 3) - 3) / 3 = 12
     

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110. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier >> subtracter >> divider).call 10 # 12
     (divider << subtracter << multiplier << adder).call 10 # 12
     (((10 + 3) * 3) - 3) / 3 = 12
     

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111. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier >> subtracter >> divider).call 10 # 12
     (divider << subtracter << multiplier << adder).call 10 # 12
     (((10 + 3) * 3) - 3) / 3 = 12
     

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112. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     

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113. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     a
     a a a
     a
     a a a a a a a a a a a a
     a
     a a a a a a a a a a a a a a a a
     

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114. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     a
     a a a
     a
     a a a a a a a a a a a a
     a
     a a a a a a a a a a a a a a a a
     s
     s s s s s s s s s s s s s s s s s s s
     s
     s s s s s s s s s s s s s s s s s s
     

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115. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     a
     a a a
     a
     a a a a a a a a a a a a
     a
     a a a a a a a a a a a a a a a a
     s
     s s s s s s s s s s s s s s s s s s s
     s
     s s s s s s s s s s s s s s s s s s
     a
     a a a a a a a a a a a a a a a a a
     a
     a a a
     a
     a a a a a a a a a a
     a
     a a a
     a
     a a a a a a a a a a a a a a a a a a
     a
     a a a
     a
     a a a a a a a a a
     

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116. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     add_and_multiply = adder >> multiplier
     subtract_and_divide = subtracter >> divider
     add_multiply_subtract_and_divide = add_and_multiply >> subtract_and_divide
     add_multiply_subtract_and_divide.call 10 # 12
     

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117. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     add_and_multiply = adder >> multiplier
     subtract_and_divide = subtracter >> divider
     add_multiply_subtract_and_divide = add_and_multiply >> subtract_and_divide
     add_multiply_subtract_and_divide.call 10 # 12
     (((10 + 3) * 3) - 3) / 3 = 12
     

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118. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     

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119. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> multiplier).call 10 # 39
     (adder << multiplier).call 10 # 33
     Order of operations matters!
     

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120. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     

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121. Composition
     https://www.alchemists.io/articles/ruby_function_composition
     (adder >> Divider.new(0) >> multiplier).call 10 # ZeroDivisionError: divided by 0
     Any error will halt the operation.
     

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122. A Better Way?
     

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123. https://www.alchemists.io/projects/transactable
     

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124. https://www.alchemists.io/projects/transactable
     Transactable
     

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125. https://www.alchemists.io/projects/transactable
     Transactable
     Dry Monads
     Composition
     

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126. https://www.alchemists.io/projects/transactable
     Transactable
     Dry Monads
     Composition
     

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127. https://www.alchemists.io/projects/transactable
     Pipeline
     (Railway Pattern)
     

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128. https://www.alchemists.io/projects/transactable
     ✅
     Pipeline
     (Railway Pattern)
     

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129. https://www.alchemists.io/projects/transactable
     ✅
     Pipeline
     (Railway Pattern)
     

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130. https://www.alchemists.io/projects/transactable
     ✅
     ✅
     Pipeline
     (Railway Pattern)
     

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131. https://www.alchemists.io/projects/transactable
     ✅
     ✅
     Pipeline
     (Railway Pattern)
     

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132. https://www.alchemists.io/projects/transactable
     ✅
     ✅
     ✅
     Pipeline
     (Railway Pattern)
     

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133. https://www.alchemists.io/projects/transactable
     ✅
     ❌
     ✅
     ✅
     Pipeline
     (Railway Pattern)
     

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134. https://www.alchemists.io/projects/transactable
     ✅
     ❌
     ✅
     ✅
     Success
     Success
     Success
     Pipeline
     (Railway Pattern)
     

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135. https://www.alchemists.io/projects/transactable
     ✅
     ❌
     ✅
     ✅
     Success
     Success
     Success
     Failure
     Failure
     Failure
     Pipeline
     (Railway Pattern)
     

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136. https://www.alchemists.io/projects/transactable
     ✅
     ❌
     ✅
     ✅
     Success
     Success
     Success
     Failure
     Failure
     Failure
     Pipeline
     No Exceptions!
     (Railway Pattern)
     

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137. https://kurzgesagt.org
     

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138. Kurzgesagt
     https://kurzgesagt.org
     

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139. Kurzgesagt
     (in a nutshell)
     https://kurzgesagt.org
     

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140. https://dry-rb.org/gems/dry-monads
     

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141. Dry Monads
     https://dry-rb.org/gems/dry-monads
     

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142. Dry Monads
     https://dry-rb.org/gems/dry-monads
     

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143. Dry Monads
     https://dry-rb.org/gems/dry-monads
     ✅ ❌
     

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144. Dry Monads
     https://dry-rb.org/gems/dry-monads
     Success
     ✅ ❌
     

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145. Dry Monads
     https://dry-rb.org/gems/dry-monads
     Success Failure
     ✅ ❌
     

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146. Dry Monads
     https://dry-rb.org/gems/dry-monads
     Success Failure
     ✅ ❌
     

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147. Dry Monads
     https://dry-rb.org/gems/dry-monads
     Success Failure
     ✅ ❌
     Ok
     

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148. Dry Monads
     https://dry-rb.org/gems/dry-monads
     Success Failure
     ✅ ❌
     Ok Err
     

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149. Dry Monads
     https://dry-rb.org/gems/dry-monads
     Success Failure
     ✅ ❌
     Ok Err
     Union Composite
     

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150. A Quick Script
     📝
     

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151. A Quick Script
     📝
     🔎
     

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152. Transactable
     https://www.alchemists.io/articles/ruby_function_composition
     

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153. Transactable
     require "bundler/inline"
     gemfile true do
     source "https://rubygems.org"
     gem "amazing_print"
     gem "debug"
     gem "http"
     gem "dry-monads"
     gem "transactable"
     end
     Install
     https://www.alchemists.io/articles/ruby_function_composition
     

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154. Transactable
     require "bundler/inline"
     gemfile true do
     source "https://rubygems.org"
     gem "amazing_print"
     gem "debug"
     gem "http"
     gem "dry-monads"
     gem "transactable"
     end
     Install
     https://www.alchemists.io/articles/ruby_function_composition
     

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155. Transactable
     require "bundler/inline"
     gemfile true do
     source "https://rubygems.org"
     gem "amazing_print"
     gem "debug"
     gem "http"
     gem "dry-monads"
     gem "transactable"
     end
     Install
     https://www.alchemists.io/articles/ruby_function_composition
     

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156. Transactable
     require "bundler/inline"
     gemfile true do
     source "https://rubygems.org"
     gem "amazing_print"
     gem "debug"
     gem "http"
     gem "dry-monads"
     gem "transactable"
     end
     Install
     https://www.alchemists.io/articles/ruby_function_composition
     

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157. Transactable
     require "bundler/inline"
     gemfile true do
     source "https://rubygems.org"
     gem "amazing_print"
     gem "debug"
     gem "http"
     gem "dry-monads"
     gem "transactable"
     end
     Install
     https://www.alchemists.io/articles/ruby_function_composition
     

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158. Transactable
     https://www.alchemists.io/articles/ruby_function_composition
     

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159. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     

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160. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     

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161. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     

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162. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     

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163. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     

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164. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     

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165. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     

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166. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     

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167. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     Domain Speci
     fi
     c Language (DSL)
     

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168. Transactable
     class Pinger
     include Transactable
     def initialize client: HTTP
     @client = client
     end
     def call url
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     end
     end
     Im
     plem
     entation
     https://www.alchemists.io/articles/ruby_function_composition
     Domain Speci
     fi
     c Language (DSL)
     

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169. Transactable
     https://www.alchemists.io/articles/ruby_function_composition
     

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170. Transactable
     class Pinger
     include Transactable
     # ...
     private
     attr_reader :client
     def get result
     result.fmap { |url| client.timeout(1).get url }
     rescue HTTP::TimeoutError => error
     Failure error.message
     end
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     

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171. Transactable
     class Pinger
     include Transactable
     # ...
     private
     attr_reader :client
     def get result
     result.fmap { |url| client.timeout(1).get url }
     rescue HTTP::TimeoutError => error
     Failure error.message
     end
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     🎗 method(:get)
     

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172. Transactable
     class Pinger
     include Transactable
     # ...
     private
     attr_reader :client
     def get result
     result.fmap { |url| client.timeout(1).get url }
     rescue HTTP::TimeoutError => error
     Failure error.message
     end
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     Monad
     

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173. Transactable
     class Pinger
     include Transactable
     # ...
     private
     attr_reader :client
     def get result
     result.fmap { |url| client.timeout(1).get url }
     rescue HTTP::TimeoutError => error
     Failure error.message
     end
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     

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174. Transactable
     class Pinger
     include Transactable
     # ...
     private
     attr_reader :client
     def get result
     result.fmap { |url| client.timeout(1).get url }
     rescue HTTP::TimeoutError => error
     Failure error.message
     end
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     Function Map
     

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175. Transactable
     class Pinger
     include Transactable
     # ...
     private
     attr_reader :client
     def get result
     result.fmap { |url| client.timeout(1).get url }
     rescue HTTP::TimeoutError => error
     Failure error.message
     end
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     

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176. Transactable
     class Pinger
     include Transactable
     # ...
     private
     attr_reader :client
     def get result
     result.fmap { |url| client.timeout(1).get url }
     rescue HTTP::TimeoutError => error
     Failure error.message
     end
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     

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177. Transactable
     class Pinger
     include Transactable
     # ...
     private
     attr_reader :client
     def get result
     result.fmap { |url| client.timeout(1).get url }
     rescue HTTP::TimeoutError => error
     Failure error.message
     end
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     

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178. Transactable
     https://www.alchemists.io/articles/ruby_function_composition
     

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179. Transactable
     class Pinger
     include Transactable
     # ...
     private
     # ...
     def report(result) = result.fmap { |status| status == 200 ? "Site is up!" : status }
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     

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180. Transactable
     class Pinger
     include Transactable
     # ...
     private
     # ...
     def report(result) = result.fmap { |status| status == 200 ? "Site is up!" : status }
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     🎗 method(:report)
     

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181. Transactable
     class Pinger
     include Transactable
     # ...
     private
     # ...
     def report(result) = result.fmap { |status| status == 200 ? "Site is up!" : status }
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     Monad
     

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182. Transactable
     class Pinger
     include Transactable
     # ...
     private
     # ...
     def report(result) = result.fmap { |status| status == 200 ? "Site is up!" : status }
     end
     Privates
     https://www.alchemists.io/articles/ruby_function_composition
     

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183. Transactable
     https://www.alchemists.io/articles/ruby_function_composition
     

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184. Transactable
     include Dry::Monads[:result]
     url = "https://xkcd.com"
     case Pinger.new.call(url)
     in Success(message) then puts "Success: #{message}"
     in Failure(error) then puts "Site is down or invalid. Reason: #{error}"
     end
     Execution
     https://www.alchemists.io/articles/ruby_function_composition
     

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185. Transactable
     include Dry::Monads[:result]
     url = "https://xkcd.com"
     case Pinger.new.call(url)
     in Success(message) then puts "Success: #{message}"
     in Failure(error) then puts "Site is down or invalid. Reason: #{error}"
     end
     Execution
     https://www.alchemists.io/articles/ruby_function_composition
     

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186. Transactable
     include Dry::Monads[:result]
     url = "https://xkcd.com"
     case Pinger.new.call(url)
     in Success(message) then puts "Success: #{message}"
     in Failure(error) then puts "Site is down or invalid. Reason: #{error}"
     end
     Execution
     https://www.alchemists.io/articles/ruby_function_composition
     Input
     

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187. Transactable
     include Dry::Monads[:result]
     url = "https://xkcd.com"
     case Pinger.new.call(url)
     in Success(message) then puts "Success: #{message}"
     in Failure(error) then puts "Site is down or invalid. Reason: #{error}"
     end
     Execution
     https://www.alchemists.io/articles/ruby_function_composition
     Transaction
     

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188. Transactable
     include Dry::Monads[:result]
     url = "https://xkcd.com"
     case Pinger.new.call(url)
     in Success(message) then puts "Success: #{message}"
     in Failure(error) then puts "Site is down or invalid. Reason: #{error}"
     end
     Execution
     https://www.alchemists.io/articles/ruby_function_composition
     

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189. View Slide

190. Output
     🔎
     

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191. Transactable
     https://www.alchemists.io/articles/ruby_function_composition
     

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192. Transactable
     Checking: https://xkcd.com...
     Success: Site is up!
     Input: https://xkcd.com
     Success
     https://www.alchemists.io/articles/ruby_function_composition
     

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193. Transactable
     https://www.alchemists.io/articles/ruby_function_composition
     

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194. Transactable
     Checking: http://xkcd.com...
     Site is down or invalid. Reason: http://xkcd.com
     Input: http://xkcd.com
     Failure
     https://www.alchemists.io/articles/ruby_function_composition
     

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195. Transactable
     https://www.alchemists.io/articles/ruby_function_composition
     

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196. Transactable
     Checking: https://www.unknown.com...
     Site is down or invalid. Reason: Timed out after using the allocated 1 seconds.
     Input: https://www.unknown.com
     Failure
     https://www.alchemists.io/articles/ruby_function_composition
     

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197. Wait, Rewind
     

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198. Wait, Rewind
     ⏪
     

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199. Transactable
     https://www.alchemists.io/projects/transactable
     

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200. Transactable
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     https://www.alchemists.io/projects/transactable
     

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201. Transactable
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     https://www.alchemists.io/projects/transactable
     

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202. Transactable
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     https://www.alchemists.io/projects/transactable
     The URL (raw input).
     

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203. Transactable
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     https://www.alchemists.io/projects/transactable
     The URL (raw input).
     Print info to the console.
     

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204. Transactable
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     https://www.alchemists.io/projects/transactable
     The URL (raw input).
     Print info to the console.
     Check if the URL is secure.
     

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205. Transactable
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     https://www.alchemists.io/projects/transactable
     The URL (raw input).
     Print info to the console.
     Check if the URL is secure.
     Make the HTTP GET request.
     

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206. Transactable
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     https://www.alchemists.io/projects/transactable
     The URL (raw input).
     Print info to the console.
     Check if the URL is secure.
     Make the HTTP GET request.
     Ask the HTTP response for status.
     

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207. Transactable
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     https://www.alchemists.io/projects/transactable
     The URL (raw input).
     Print info to the console.
     Check if the URL is secure.
     Make the HTTP GET request.
     Ask the HTTP response for status.
     Report the HTTP status.
     

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208. Transactable
     https://www.alchemists.io/projects/transactable
     Pipe
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     

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209. Transactable
     https://www.alchemists.io/projects/transactable
     Pipe
     method :get
     url
     tee
     check
     as
     method :report
     ↓
     ↓
     ↓
     ↓
     ↓
     pipe url,
     tee(Kernel, :puts, "Checking: #{url}..."),
     check(/\Ahttps/, :match?),
     method(:get),
     as(:status),
     method(:report)
     

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210. Architecture
     https://www.alchemists.io/projects/transactable
     method :get
     url
     tee
     check
     as
     method :report
     ↓
     ↓
     ↓
     ↓
     ↓
     

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211. Architecture
     https://www.alchemists.io/projects/transactable
     method :get
     url
     tee
     check
     as
     method :report
     ↓
     ↓
     ↓
     ↓
     ↓
     Input
     

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212. Architecture
     https://www.alchemists.io/projects/transactable
     method :get
     url
     tee
     check
     as
     method :report
     ↓
     ↓
     ↓
     ↓
     ↓
     Step
     Step
     Step
     Step
     Step
     

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213. Architecture
     https://www.alchemists.io/projects/transactable
     method :get
     url
     tee
     check
     as
     method :report
     ↓
     ↓
     ↓
     ↓
     ↓
     Monad
     Monad
     Monad
     Monad
     Monad
     

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214. Architecture
     https://www.alchemists.io/projects/transactable
     method :get
     url
     tee
     check
     as
     method :report
     ↓
     ↓
     ↓
     ↓
     ↓
     Pipe
     

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215. Architecture
     https://www.alchemists.io/projects/transactable
     method :get
     url
     tee
     check
     as
     method :report
     ↓
     ↓
     ↓
     ↓
     ↓
     Pipe
     

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216. Architecture
     https://www.alchemists.io/projects/transactable
     method :get
     url
     tee
     check
     as
     method :report
     ↓
     ↓
     ↓
     ↓
     ↓
     Pipe
     

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217. Architecture
     https://www.alchemists.io/projects/transactable
     method :get
     url
     tee
     check
     as
     method :report
     ↓
     ↓
     ↓
     ↓
     ↓
     Pipe
     

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218. https://www.alchemists.io/projects/transactable
     

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219. https://www.alchemists.io/projects/transactable
     Transactable
     Dry Monads
     Composition
     

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220. Thanks
     

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221. 🙇
     Thanks
     

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222. Let's Connect!
     

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223. Let's Connect!
     https://www.alchemists.io
     @bkuhlmann@mastodon.social
     🌎
     

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224. Let's Connect!
     https://www.alchemists.io
     @bkuhlmann@mastodon.social
     🌎
     Write
     ✍
     Speak
     🎓
     Develop
     Screencast
     🎥
     Consult
     👥
     

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225. Let's Connect!
     https://www.alchemists.io
     @bkuhlmann@mastodon.social
     🌎
     Write
     ✍
     Speak
     🎓
     Develop
     Screencast
     🎥
     Ruby
     Elm
     HTMX
     Hanami
     Dry RB
     ROM
     Git
     Terraform
     Consult
     👥
     

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