Composing Software

Description

Table of Contents......Page 3 Thank You......Page 8 Composing Software: An Introduction......Page 9 You Compose Software Every Day......Page 10 Conclusion......Page 17 Forward......Page 18 The Rise of Functional Programming......Page 20 The Rise of Functional Programming......Page 23 Functional Programming Has Always Been Alive and Well......Page 24 Why Learn Functional Programming in JavaScript?......Page 25 Mapping......Page 32 Pure Functions......Page 33 The Trouble with Shared State......Page 34 Same Input, Same Output......Page 35 No Side Effects......Page 36 Conclusion......Page 39 What is Functional Programming?......Page 40 Shared State......Page 41 Immutability......Page 44 Reusability Through Higher Order Functions......Page 45 Containers, Functors, Lists, and Streams......Page 46 Declarative vs Imperative......Page 47 Conclusion......Page 48 Expressions and Values......Page 50 Types......Page 51 Destructuring......Page 52 Comparisons and Ternaries......Page 53 Functions......Page 54 Currying......Page 58 Function Composition......Page 60 Method Chaining......Page 61 Conclusion......Page 62 Higher Order Functions......Page 63 What is a curried function?......Page 66 What is point-free style?......Page 67 Why do we curry?......Page 68 Trace......Page 70 Curry and Function Composition, Together......Page 71 Conclusion......Page 76 Abstraction & Composition......Page 78 Abstraction in Software......Page 79 Abstraction through composition......Page 80 How to Do More with Less Code......Page 81 Reduce......Page 82 Reduce is Versatile......Page 83 Conclusion......Page 87 Functors & Categories......Page 88 Why Functors?......Page 89 Functor Laws......Page 92 Category Theory......Page 94 Build Your Own Functor......Page 96 Curried Map......Page 97 Conclusion......Page 98 Monads......Page 99 You're probably already using monads.......Page 101 What Monads are Made of......Page 106 Building a Kleisli Composition Function......Page 109 The Monad Laws......Page 112 Conclusion......Page 115 The Forgotten History of OOP......Page 117 The Big Idea......Page 118 The Essence of OOP......Page 120 What OOP Doesn't Mean......Page 121 What is an object?......Page 123 We've lost the plot.......Page 124 Object Composition......Page 126 What is Object Composition?......Page 127 Notes on Code Examples......Page 128 Aggregation......Page 129 Concatenation......Page 131 Delegation......Page 132 Conclusion......Page 134 Factory Functions......Page 136 Literals for One, Factories for Many......Page 137 Destructuring......Page 138 Computed Property Keys......Page 139 Default Parameters......Page 140 Type Inference......Page 141 Factory Functions for Mixin Composition......Page 143 Conclusion......Page 145 Motivation......Page 147 What are mixins?......Page 148 What is functional inheritance?......Page 149 What is a functional mixin?......Page 150 Composing Functional Mixins......Page 151 Caveats......Page 152 Conclusion......Page 157 The Delegate Prototype......Page 158 The .constructor Property......Page 160 Class to Factory is a Breaking Change......Page 163 Composable Custom Data Types......Page 169 Composable Currency......Page 172 Lenses......Page 174 Background......Page 175 Lens Laws......Page 176 Composing Lenses......Page 178 Transducers......Page 181 Why Transducers?......Page 182 Background and Etymology......Page 184 A Musical Analogy for Transducers......Page 186 Transducer Rules......Page 192 Transducing......Page 194 The Transducer Protocol......Page 196 Conclusion......Page 197 1. Make the function the unit of composition. One job for each function.......Page 199 2. Omit needless code.......Page 200 3. Use active voice.......Page 204 4. Avoid a succession of loose statements.......Page 205 6. Put statements and expressions in positive form.......Page 207 7. Use parallel code for parallel concepts.......Page 209 Conclusion: Code should be simple, not simplistic.......Page 210 TDD should lead to better design.......Page 212 What is a mock?......Page 213 What is test coverage?......Page 214 What is tight coupling?......Page 215 What does composition have to do with mocking?......Page 216 How do we remove coupling?......Page 219 ``Code smells'' are warning signs, not laws. Mocks are not evil.......Page 227