The Art of Modern PHP 8: Learn how to write modern, performant, and enterprise-ready code with the latest PHP features and practices

Cover....1 Title....2 Copyright and Credits....2 Foreword....4 Table of Contents....10 Section 1 – PHP 8 OOP....22 Chapter 1: Object-Oriented PHP....24 What is OOP?....25 Understanding the phrase....25 OOP alternatives....28 Learning object-oriented PHP....31 PHP OOP basics....36 Classes....36 Interfaces....41 Namespaces....42 Summary....44 Chapter 2: Inheritance and Composition, Encapsulation and Visibility, Interfaces and Concretions....46 Encapsulation and visibility....47 Private, protected, and public....48 Inheritance–the classical parent, child, and "is a" style....49 Constructor promotion....63 Composition–the modern, flexible "has a" style....70 Interfaces instead of abstract classes....81 Summary....82 Chapter 3: Advanced OOP Features....84 SPL – the Standard PHP Library....85 Data structures....85 Iterators....86 Exceptions and error handling....100 Yoda and Pokemon exception handling....107 Exception and error handling best practices....108 Meta-programming with reflection and attributes....112 Reflection....112 Attributes....115 Summary....120 Section 2 – PHP Types....122 Chapter 4: Scalar, Arrays, and Special Types....124 Scalar types....126 Strings....126 Ints....134 Floats....135 Bools....138 Type juggling....139 Type and value comparison....139 Arrays and iterables....145 Arrays....145 Iterables....149 DocBlock types....152 Nullable, void, and uninitialised....154 Null and nullable....154 Void....157 Uninitialised....159 Resources....160 Summary....162 Chapter 5: Object Types, Interfaces, and Unions....164 Object type inheritance....165 Object comparison....174 Passing objects by reference....177 Making new objects....179 Summary....188 Chapter 6: Parameter, Property, and Return Types....190 Coercive and strict modes....191 Covariance and contravariance....203 Contravariance – that is, allowing less specific parameter types than the parent....204 Covariance – that is, allowing more specific return types than the parent....204 Remembering the rules....210 Summary....210 Section 3 – Clean PHP 8 Patterns and Style....212 Chapter 7: Design Patterns and Clean Code....214 Clean Code Acronyms (CCA)....216 DRY....223 KICK....224 Design patterns....239 Creational patterns....239 Structural patterns....242 Behavioral patterns....247 Architectural patterns....249 Summary....250 Chapter 8: Model, View, Controller (MVC) Example....252 Model, View, Controller – MVC....253 Controller....253 Front controller....254 Model....268 Entity pattern....268 Universally unique identifier (UUID)....270 Persistence and ORM....273 Singleton anti-pattern....274 Repository pattern....274 Collection pattern....276 View....279 It lives....286 Summary....292 Chapter 9: Dependency Injection Example....294 Inversion of control container....295 Dependency injection and the service locator....295 The service locator anti-pattern....316 Summary....317 Chapter 10: Composer For Dependencies....322 What is Composer?....323 What are dependencies?....323 Dependency resolution....324 But wait, there's more....325 In a nutshell, it's awesome....325 Get it installed!....326 Composer autoloader....326 Old-fashioned versus autoloaded....326 A real-world, old-fashioned example....329 Extra points....330 Autoloading in PHP....330 Configuring Composer autoloader....333 Using Composer to require packages....334 Finding dependencies....334 Initialisation of composer.json....335 What is a vendor?....336 Minimum stability....336 Package type....336 License....337 So far, so good....337 Installing monolog....338 Ignore the vendor directory in your VCS....341 The composer.lock file....341 Adding extra dependencies....342 Version constraints....344 Semver in a nutshell....344 Caret (^) Version Range....345 Tilde (~) Version Range....345 Exact version....346 Version range....346 Multiple acceptable versions....346 Full documentation....347 Dev and prod dependencies....347 Requiring dev dependencies....347 Installing without dev dependencies....348 Summary....348 Chapter 11: Creating Your Own Composer Package....350 Writing composer.json....351 Name....353 Description....353 Keywords....353 License....353 Using source folders and namespaces....354 Executable Binaries Configured under bin....356 Extensionless files....358 Executable permissions....358 Finding an autoloader....358 Using versions and tagging....358 Creating a Git tag....359 SemVer....360 Stable and development versions....361 Private Git repos as Composer dependencies....362 Publishing on Packagist....363 Things to check before you publish....363 Submitting your package to Packagist....364 Created....365 If you were just testing, delete it....366 Summary....367 Section 5 – Bonus Section - PHP 8.1....368 Chapter 12: The Awesomeness That Is 8.1....370 Enumerations....371 Basic and backed enums....371 Creating enum instances....374 Not just classes with cases....376 Readonly properties....377 Readonly gotchas....386 Intersection types....392 Never return type....398 Final constants....400 Summary – end of the book....405 Other Books You May Enjoy....409 Index....412