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 Brooke Kuhlmann g(f(x)) f(x) x A B C f g alchemists.io
2. Overview alchemists.io
3. Ruby Overview Fundamentals alchemists.io
4. Dry Monads Ruby Overview Fundamentals Railway Pattern alchemists.io
5. Pipeable Dry Monads Ruby Overview Fundamentals Railway Pattern Fault tolerent pipelines alchemists.io
6. What? alchemists.io
7. en.wikipedia.org/wiki/Function_composition_(computer_science) What alchemists.io
8. 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 alchemists.io
9. alchemists.io/articles/ruby_function_composition What alchemists.io
10. alchemists.io/articles/ruby_function_composition What alchemists.io
11. alchemists.io/articles/ruby_function_composition What alchemists.io
12. alchemists.io/articles/ruby_function_composition What alchemists.io
13. alchemists.io/articles/ruby_function_composition What 1 alchemists.io
14. alchemists.io/articles/ruby_function_composition What 1 2 alchemists.io
15. alchemists.io/articles/ruby_function_composition What 1 2 3 alchemists.io
16. What alchemists.io/articles/ruby_function_composition alchemists.io
17. What (5 + 3) * 3 = 24 alchemists.io/articles/ruby_function_composition alchemists.io
18. History alchemists.io
19. History alchemists.io/articles/ruby_function_composition alchemists.io
20. History Ruby 2.6.0 alchemists.io/articles/ruby_function_composition alchemists.io
21. History Ruby 2.6.0 Methods: #>> #<< (forward composition) (backward composition) alchemists.io/articles/ruby_function_composition alchemists.io
22. History Ruby 2.6.0 Methods: Proc Method #>> #<< Objects: (forward composition) (backward composition) alchemists.io/articles/ruby_function_composition alchemists.io
23. Fundamentals alchemists.io
24. Fundamentals alchemists.io/articles/ruby_function_composition alchemists.io
25. Fundamentals Procs Lambdas Methods Classes alchemists.io/articles/ruby_function_composition alchemists.io
26. Fundamentals alchemists.io/articles/ruby_function_composition alchemists.io
27. Fundamentals m m m 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 alchemists.io/articles/ruby_function_composition alchemists.io
28. Fundamentals m m m 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 alchemists.io/articles/ruby_function_composition alchemists.io
29. Fundamentals m m m 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 alchemists.io/articles/ruby_function_composition alchemists.io
30. Fundamentals m m m 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 alchemists.io/articles/ruby_function_composition alchemists.io
31. Fundamentals m m m 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 alchemists.io/articles/ruby_function_composition alchemists.io
32. Fundamentals multiplier = proc { |number, by = 3| number * by } multiplier.class # Proc multiplier.inspect # #<Proc:0x00000001059b5248 (irb):22> multiplier.call 3 # 9 multiplier.call 3, 10 # 30 Procs alchemists.io/articles/ruby_function_composition alchemists.io
33. Fundamentals alchemists.io/articles/ruby_function_composition alchemists.io
34. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
35. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
36. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
37. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
38. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
39. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
40. Fundamentals multiplier = -> number, by = 3 { number * by } multiplier.class # Proc multiplier.inspect # "#<Proc:0x0000000104ba68a0 (irb):19 (lambda)>" multiplier.call 3 # 9 multiplier.call 3, 10 # 30 Lam bdas alchemists.io/articles/ruby_function_composition alchemists.io
41. Fundamentals alchemists.io/articles/ruby_function_composition alchemists.io
42. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
43. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
44. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
45. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
46. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
47. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
48. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
49. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
50. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
51. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
52. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
53. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
54. Fundamentals Calculate = Module.new { def self.multiply(number, by = 3) = number * by } multiplier = Calculate.method :multiply multiplier.class # Method multiplier.inspect # "#<Method: Calculate.multiply(number, by=...) (irb):1>" multiplier.call 3 # 9 multiplier.call 3, 10 # 30 function = multiplier.to_proc function.class # Proc function.inspect # #<Proc:0x0000000104906f78 (lambda)> M ethods alchemists.io/articles/ruby_function_composition alchemists.io
55. Fundamentals Calculate = Module.new { def self.multiply(number, by = 3) = number * by } multiplier = Calculate.method :multiply multiplier.class # Method multiplier.inspect # "#<Method: Calculate.multiply(number, by=...) (irb):1>" multiplier.call 3 # 9 multiplier.call 3, 10 # 30 function = multiplier.to_proc function.class # Proc function.inspect # #<Proc:0x0000000104906f78 (lambda)> M ethods alchemists.io/articles/ruby_function_composition alchemists.io
56. Fundamentals alchemists.io/articles/ruby_function_composition alchemists.io
57. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
58. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
59. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
60. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
61. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
62. Fundamentals 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 alchemists.io/articles/ruby_function_composition alchemists.io
63. Fundamentals 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 # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # m m m m m m m m m m m m m m m 3 # # C lasses alchemists.io/articles/ruby_function_composition alchemists.io
64. Fundamentals 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:0x0000000103761908 @by=3>" multiplier.call 3 # 9 Multiplier.new(10).call 3 # 30 C lasses alchemists.io/articles/ruby_function_composition alchemists.io
65. Fundamentals 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:0x0000000103761908 @by=3>" multiplier.call 3 # 9 Multiplier.new(10).call 3 # 30 C lasses alchemists.io/articles/ruby_function_composition alchemists.io
66. alchemists.io
67. Composition alchemists.io
68. Composition Procs Lambdas Methods Classes >> >> >> alchemists.io/articles/ruby_function_composition alchemists.io
69. Composition Procs Lambdas Methods Classes >> >> >> alchemists.io/articles/ruby_function_composition alchemists.io
70. Composition Procs Lambdas Methods Classes >> >> >> alchemists.io/articles/ruby_function_composition alchemists.io
71. Composition Procs Lambdas Methods Classes >> >> >> alchemists.io/articles/ruby_function_composition alchemists.io
72. Composition alchemists.io/articles/ruby_function_composition alchemists.io
73. Composition © Wallpaper Cave Some assembly required. alchemists.io/articles/ruby_function_composition alchemists.io
74. Composition alchemists.io/articles/ruby_function_composition alchemists.io
75. 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 alchemists.io/articles/ruby_function_composition alchemists.io
76. 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 alchemists.io/articles/ruby_function_composition alchemists.io
77. 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 Pipeable alchemists.io/articles/ruby_function_composition alchemists.io
78. Composition Class alchemists.io/articles/ruby_function_composition alchemists.io
79. Composition class Divider include Composable def initialize by = 3 @by = by end def call(number) = number / by private attr_reader :by end Class alchemists.io/articles/ruby_function_composition alchemists.io
80. Composition class Divider include Composable def initialize by = 3 @by = by end def call(number) = number / by private attr_reader :by end Class alchemists.io/articles/ruby_function_composition alchemists.io
81. Composition Method alchemists.io/articles/ruby_function_composition alchemists.io
82. Composition module Calculate def self.multiply(number, by = 3) = number * by end Method alchemists.io/articles/ruby_function_composition alchemists.io
83. Composition alchemists.io/articles/ruby_function_composition alchemists.io
84. Composition adder = proc { |number, by = 3| number + by } subtracter = -> number, by = 3 { number - by } divider = Divider.new multiplier = Calculate.method :multiply alchemists.io/articles/ruby_function_composition alchemists.io
85. Composition adder = proc { |number, by = 3| number + by } subtracter = -> number, by = 3 { number - by } divider = Divider.new multiplier = Calculate.method :multiply Proc alchemists.io/articles/ruby_function_composition alchemists.io
86. Composition adder = proc { |number, by = 3| number + by } subtracter = -> number, by = 3 { number - by } divider = Divider.new multiplier = Calculate.method :multiply Proc Lambda alchemists.io/articles/ruby_function_composition alchemists.io
87. Composition adder = proc { |number, by = 3| number + by } subtracter = -> number, by = 3 { number - by } divider = Divider.new multiplier = Calculate.method :multiply Proc Lambda Class alchemists.io/articles/ruby_function_composition alchemists.io
88. 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 alchemists.io/articles/ruby_function_composition alchemists.io
89. 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 alchemists.io/articles/ruby_function_composition alchemists.io
90. Composition multiplier (method) subtractor (lambda) adder (proc) divider (class) >> >> >> alchemists.io/articles/ruby_function_composition alchemists.io
91. Composition multiplier (method) subtractor (lambda) adder (proc) divider (class) >> >> >> alchemists.io/articles/ruby_function_composition alchemists.io
92. Composition alchemists.io/articles/ruby_function_composition alchemists.io
93. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 alchemists.io/articles/ruby_function_composition alchemists.io
94. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 Forward composition alchemists.io/articles/ruby_function_composition alchemists.io
95. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 Forward composition Backward composition alchemists.io/articles/ruby_function_composition alchemists.io
96. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 alchemists.io/articles/ruby_function_composition alchemists.io
97. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 alchemists.io/articles/ruby_function_composition alchemists.io
98. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 (10 + 3) * 3 = 39 alchemists.io/articles/ruby_function_composition alchemists.io
99. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 (10 + 3) * 3 = 39 📖 alchemists.io/articles/ruby_function_composition alchemists.io
100. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 (10 + 3) * 3 = 39 📖 1 alchemists.io/articles/ruby_function_composition alchemists.io
101. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 (10 + 3) * 3 = 39 📖 1 alchemists.io/articles/ruby_function_composition alchemists.io
102. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 (10 + 3) * 3 = 39 📖 1 alchemists.io/articles/ruby_function_composition alchemists.io
103. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 (10 + 3) * 3 = 39 📖 1 2 alchemists.io/articles/ruby_function_composition alchemists.io
104. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 (10 + 3) * 3 = 39 📖 1 2 alchemists.io/articles/ruby_function_composition alchemists.io
105. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 alchemists.io/articles/ruby_function_composition alchemists.io
106. Composition (adder >> multiplier).call 10 # 39 (multiplier << adder).call 10 # 39 ⭐ alchemists.io/articles/ruby_function_composition alchemists.io
107. Composition alchemists.io/articles/ruby_function_composition alchemists.io
108. Composition (adder >> multiplier >> subtracter >> divider).call 10 # 12 (divider << subtracter << multiplier << adder).call 10 # 12 alchemists.io/articles/ruby_function_composition alchemists.io
109. Composition (adder >> multiplier >> subtracter >> divider).call 10 # 12 (divider << subtracter << multiplier << adder).call 10 # 12 (((10 + 3) * 3) - 3) / 3 = 12 alchemists.io/articles/ruby_function_composition alchemists.io
110. Composition (adder >> multiplier >> subtracter >> divider).call 10 # 12 (divider << subtracter << multiplier << adder).call 10 # 12 (((10 + 3) * 3) - 3) / 3 = 12 alchemists.io/articles/ruby_function_composition alchemists.io
111. Composition (adder >> multiplier >> subtracter >> divider).call 10 # 12 (divider << subtracter << multiplier << adder).call 10 # 12 (((10 + 3) * 3) - 3) / 3 = 12 alchemists.io/articles/ruby_function_composition alchemists.io
112. Composition alchemists.io/articles/ruby_function_composition alchemists.io
113. 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 alchemists.io/articles/ruby_function_composition alchemists.io
114. 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 alchemists.io/articles/ruby_function_composition alchemists.io
115. 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 alchemists.io/articles/ruby_function_composition alchemists.io
116. 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 alchemists.io/articles/ruby_function_composition alchemists.io
117. 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 alchemists.io/articles/ruby_function_composition alchemists.io
118. Composition alchemists.io/articles/ruby_function_composition alchemists.io
119. Composition (adder >> multiplier).call 10 # 39 (adder << multiplier).call 10 # 33 Order of operations matters! alchemists.io/articles/ruby_function_composition alchemists.io
120. Composition alchemists.io/articles/ruby_function_composition alchemists.io
121. Composition (adder >> Divider.new(0) >> multiplier).call 10 # ZeroDivisionError: divided by 0 Any error will halt the operation. alchemists.io/articles/ruby_function_composition alchemists.io
122. A Better Way? alchemists.io
123. alchemists.io/projects/pipeable alchemists.io
124. alchemists.io/projects/pipeable Pipeable alchemists.io
125. Pipeable Dry Monads Composition alchemists.io alchemists.io/projects/pipeable
126. Pipeable Dry Monads Composition alchemists.io alchemists.io/projects/pipeable
127. Pipeline (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
128. ✅ Pipeline (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
129. ✅ Pipeline (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
130. ✅ ✅ Pipeline (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
131. ✅ ✅ Pipeline (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
132. ✅ ✅ ✅ Pipeline (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
133. ✅ ❌ ✅ ✅ Pipeline (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
134. ✅ ❌ ✅ ✅ Success Success Success Pipeline (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
135. ✅ ❌ ✅ ✅ Success Success Success Failure Failure Failure Pipeline (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
136. ✅ ❌ ✅ ✅ Success Success Success Failure Failure Failure Pipeline No Exceptions! (Railway Pattern) alchemists.io alchemists.io/projects/pipeable
137. kurzgesagt.org alchemists.io
138. Kurzgesagt kurzgesagt.org alchemists.io
139. Kurzgesagt (in a nutshell) kurzgesagt.org alchemists.io
140. dry-rb.org/gems/dry-monads alchemists.io
141. Dry Monads dry-rb.org/gems/dry-monads alchemists.io
142. Dry Monads dry-rb.org/gems/dry-monads alchemists.io
143. Dry Monads dry-rb.org/gems/dry-monads ✅ ❌ alchemists.io
144. Dry Monads dry-rb.org/gems/dry-monads Success ✅ ❌ alchemists.io
145. Dry Monads dry-rb.org/gems/dry-monads Success Failure ✅ ❌ alchemists.io
146. Dry Monads dry-rb.org/gems/dry-monads Success Failure ✅ ❌ alchemists.io
147. Dry Monads dry-rb.org/gems/dry-monads Success Failure ✅ ❌ Ok alchemists.io
148. Dry Monads dry-rb.org/gems/dry-monads Success Failure ✅ ❌ Ok Err alchemists.io
149. Dry Monads dry-rb.org/gems/dry-monads Success Failure ✅ ❌ Ok Err Union Composite alchemists.io
150. A Quick Script 📝 alchemists.io
151. A Quick Script 📝 🔎 alchemists.io
152. Pipeable alchemists.io/articles/ruby_function_composition alchemists.io
153. Pipeable require "bundler/inline" gemfile true do source "https://rubygems.org" gem "amazing_print" gem "debug" gem "http" gem "dry-monads" gem "pipeable" end Install alchemists.io/articles/ruby_function_composition alchemists.io
154. Pipeable require "bundler/inline" gemfile true do source "https://rubygems.org" gem "amazing_print" gem "debug" gem "http" gem "dry-monads" gem "pipeable" end Install alchemists.io/articles/ruby_function_composition alchemists.io
155. Pipeable require "bundler/inline" gemfile true do source "https://rubygems.org" gem "amazing_print" gem "debug" gem "http" gem "dry-monads" gem "pipeable" end Install alchemists.io/articles/ruby_function_composition alchemists.io
156. Pipeable require "bundler/inline" gemfile true do source "https://rubygems.org" gem "amazing_print" gem "debug" gem "http" gem "dry-monads" gem "pipeable" end Install alchemists.io/articles/ruby_function_composition alchemists.io
157. Pipeable require "bundler/inline" gemfile true do source "https://rubygems.org" gem "amazing_print" gem "debug" gem "http" gem "dry-monads" gem "pipeable" end Install alchemists.io/articles/ruby_function_composition alchemists.io
158. alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
159. class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
160. class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
161. class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
162. class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
163. class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
164. class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
165. class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
166. Pipeable class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation alchemists.io/articles/ruby_function_composition alchemists.io
167. Pipeable class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation Domain Speci fi c Language (DSL) alchemists.io/articles/ruby_function_composition alchemists.io
168. Pipeable class Pinger include Pipeable def initialize client: HTTP @client = client end def call url pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report end end Im plem entation Domain Speci fi c Language (DSL) alchemists.io/articles/ruby_function_composition alchemists.io
169. alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
170. class Pinger include Pipeable # ... 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 alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
171. class Pinger include Pipeable # ... 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 🎗:get alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
172. class Pinger include Pipeable # ... 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 Monad alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
173. class Pinger include Pipeable # ... 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 alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
174. class Pinger include Pipeable # ... 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 Function Map alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
175. class Pinger include Pipeable # ... 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 alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
176. class Pinger include Pipeable # ... 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 alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
177. class Pinger include Pipeable # ... 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 alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
178. alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
179. class Pinger include Pipeable # ... private # ... def report(result) = result.fmap { |status| status == 200 ? "Site is up!" : status } end Privates alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
180. class Pinger include Pipeable # ... private # ... def report(result) = result.fmap { |status| status == 200 ? "Site is up!" : status } end Privates 🎗:report alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
181. class Pinger include Pipeable # ... private # ... def report(result) = result.fmap { |status| status == 200 ? "Site is up!" : status } end Privates Monad alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
182. class Pinger include Pipeable # ... private # ... def report(result) = result.fmap { |status| status == 200 ? "Site is up!" : status } end Privates alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
183. alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
184. 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 alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
185. 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 alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
186. 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 Input alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
187. 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 Pipe alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
188. 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 alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
189. alchemists.io
190. Output 🔎 alchemists.io
191. alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
192. Checking: https://xkcd.com... Success: Site is up! Input: https://xkcd.com Success alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
193. alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
194. Checking: http://xkcd.com... Site is down or invalid. Reason: http://xkcd.com Input: http://xkcd.com Failure alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
195. alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
196. 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 alchemists.io/articles/ruby_function_composition alchemists.io Pipeable
197. Wait, Rewind alchemists.io
198. Wait, Rewind ⏪ alchemists.io
199. alchemists.io alchemists.io/projects/pipeable Pipeable
200. pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report alchemists.io alchemists.io/projects/pipeable Pipeable
201. pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report alchemists.io alchemists.io/projects/pipeable Pipeable
202. pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report The URL (raw input). alchemists.io alchemists.io/projects/pipeable Pipeable
203. pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report The URL (raw input). Print info to the console. alchemists.io alchemists.io/projects/pipeable Pipeable
204. pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report The URL (raw input). Print info to the console. Check if the URL is secure. alchemists.io alchemists.io/projects/pipeable Pipeable
205. pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report The URL (raw input). Print info to the console. Check if the URL is secure. Make the HTTP GET request. alchemists.io alchemists.io/projects/pipeable Pipeable
206. pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report 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. alchemists.io alchemists.io/projects/pipeable Pipeable
207. pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report 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. alchemists.io alchemists.io/projects/pipeable Pipeable
208. Pipe pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report alchemists.io alchemists.io/projects/pipeable Pipeable
209. Pipe :get url tee check as :report ↓ ↓ ↓ ↓ ↓ pipe url, tee(Kernel, :puts, "Checking: #{url}..."), check(/\Ahttps/, :match?), :get, as(:status), :report alchemists.io alchemists.io/projects/pipeable Pipeable
210. Architecture :get url tee check as :report ↓ ↓ ↓ ↓ ↓ alchemists.io alchemists.io/projects/pipeable
211. Architecture :get url tee check as :report ↓ ↓ ↓ ↓ ↓ Input alchemists.io alchemists.io/projects/pipeable
212. Architecture :get url tee check as :report ↓ ↓ ↓ ↓ ↓ Step Step Step Step Step alchemists.io alchemists.io/projects/pipeable
213. Architecture :get url tee check as :report ↓ ↓ ↓ ↓ ↓ Monad Monad Monad Monad Monad alchemists.io alchemists.io/projects/pipeable
214. Architecture :get url tee check as :report ↓ ↓ ↓ ↓ ↓ Pipe alchemists.io alchemists.io/projects/pipeable
215. Architecture :get url tee check as :report ↓ ↓ ↓ ↓ ↓ Pipe alchemists.io alchemists.io/projects/pipeable
216. Architecture :get url tee check as :report ↓ ↓ ↓ ↓ ↓ Pipe alchemists.io alchemists.io/projects/pipeable
217. Architecture :get url tee check as :report ↓ ↓ ↓ ↓ ↓ Pipe alchemists.io alchemists.io/projects/pipeable
218. alchemists.io alchemists.io/projects/pipeable
219. Pipeable Dry Monads Composition alchemists.io alchemists.io/projects/pipeable
220. Thanks alchemists.io
221. 🙇 Thanks alchemists.io
222. @bkuhlmann@mastodon.social Let's Connect! alchemists.io