Essential F#: Succinct. Robust. Performant

Table of Contents....3 Preface....7 Contents....8 F# Software Foundation....10 About the author....10 Acknowledgments....11 Getting Started....12 Setting up your environment....12 One Last Thing....13 1 - An Introductory Domain Modelling Exercise....14 The Problem....14 Getting Started....15 Making the Implicit Explicit....22 Going Further....24 Alternative Approaches (1 of 2)....27 Alternative Approaches (2 of 2)....28 Summary....30 Postscript....31 2 - Functions....32 Getting Started....32 Theory....32 In Practice....33 Unit....36 Anonymous Functions....37 Multiple Parameters....38 Partial Application (Part 1)....39 The Forward Pipe Operator....39 Partial Application (Part 2)....42 Summary....44 3 - Null and Exception Handling....45 Null Handling....45 Interop With .NET....48 Handling Exceptions....49 Function Composition With Result....51 Summary....57 4 - Organising Code and Testing....58 Getting Started....58 Solutions and Projects....58 Adding a Source File....58 Namespaces and Modules....59 Writing Tests....62 Writing Real Tests....63 Using FsUnit for Assertions....67 Summary....68 5 - Introduction to Collections....69 Before We Start....69 The Basics....69 Core Functionality....69 Folding....74 Grouping Data and Uniqueness....75 Solving a Problem in Many Ways....76 Working Through a Practical Example....77 Summary....85 6 - Reading Data From a File....86 Setting Up....86 Loading Data....86 Parsing Data....89 Testing the Code....91 Final Code....93 Summary....95 7 - Active Patterns....96 Setting Up....96 Partial Active Patterns....96 Parameterized Partial Active Patterns....98 Multi-Case Active Patterns....102 Single-Case Active Patterns....103 Using Active Patterns in a Practical Example....105 Summary....108 8 - Functional Validation....109 Setting Up....109 Solving the Problem....111 Where are we now?....116 Functional Validation the F# Way....120 Summary....123 9 - Single-Case Discriminated Union....124 Setting Up....124 Solving the Problem....124 Using Modules....131 A Few Minor Improvements....133 Using a Record Type....135 Summary....135 10 - Object Programming....136 Setting Up....136 Class Types....136 Interfaces....138 Object Expressions....140 Encapsulation....142 Equality....144 Summary....146 11 - Recursion....147 Setting Up....147 Solving The Problem....147 Tail Call Optimisation....148 Expanding the Accumulator....149 Using Recursion to Solve FizzBuzz....150 Quicksort using recursion....151 Recursion with Hierarchical Data....152 Other Uses Of Recursion....158 Summary....158 12 - Computation Expressions....159 Setting Up....159 Introduction....159 The Result Computation Expression....162 Introduction to Async....164 Compound Computation Expressions....165 Debugging Code....170 Further Reading....170 Summary....171 13 - Introduction to Web Programming with Giraffe....172 Getting Started....172 Using Giraffe....173 Creating an API Route....176 Creating a Custom HttpHandler....177 Creating a View....178 Adding Subroutes....179 Reviewing the Code....181 Summary....183 14 - Creating an API with Giraffe....184 Getting Started....184 Our Task....184 Sample Data....184 Routes....185 Handlers....187 Using the API....189 Summary....190 15 - Creating Web Pages with Giraffe....191 Getting Started....191 Configuration....191 Adding a Master Page....192 Creating the Todo List View....193 Loading Data on Startup....195 Summary....197 Summary....198 F# Software Foundation....199 Resources....199 And Finally....200 Appendix 1....201 Creating Solutions and Projects in VS Code....201 Appendix 2....203 CSS and JavaScript for Chapter 15....203