Hands-On Design Patterns and Best Practices with Julia

▶Book Description
Design patterns are fundamental techniques for developing reusable and maintainable code. They provide a set of proven solutions that allow developers to solve problems in software development quickly. This book will demonstrate how to leverage design patterns with real-world applications.

Starting with an overview of design patterns and best practices in application design, you'll learn about some of the most fundamental Julia features such as modules, data types, functions/interfaces, and metaprogramming. You'll then get to grips with the modern Julia design patterns for building large-scale applications with a focus on performance, reusability, robustness, and maintainability. The book also covers anti-patterns and how to avoid common mistakes and pitfalls in development. You'll see how traditional object-oriented patterns can be implemented differently and more effectively in Julia. Finally, you'll explore various use cases and examples, such as how expert Julia developers use design patterns in their open source packages.

By the end of this Julia programming book, you'll have learned methods to improve software design, extensibility, and reusability, and be able to use design patterns efficiently to overcome common challenges in software development.

▶What You Will Learn
- Master the Julia language features that are key to developing large-scale software applications
- Discover design patterns to improve overall application architecture and design
- Develop reusable programs that are modular, extendable, performant, and easy to maintain
- Weigh up the pros and cons of using different design patterns for use cases
- Explore methods for transitioning from object-oriented programming to using equivalent or more advanced Julia techniques

▶Key Features
- Explore useful design patterns along with object-oriented programming in Julia 1.0
- Implement macros and metaprogramming techniques to make your code faster, concise, and efficient
- Develop the skills necessary to implement design patterns for creating robust and maintainable applications

▶Who This Book Is For
This book is for beginner to intermediate-level Julia programmers who want to enhance their skills in designing and developing large-scale applications.

▶What this book covers
- Chapter 1, Design Patterns and Related Principles, introduces the history of design patterns and how they are useful for developing applications. It covers several industry-standard software design principles that are applicable across any programming language and paradigm.

- Chapter 2, Modules, Packages, and Data Type Concepts, discusses how larger programs can be organized and how dependencies can be managed. Then, it explains how to develop new data types and express their relationship in a custom type hierarchy.

- Chapter 3, Designing Functions and Interfaces, explains how functions are defined and how multiple dispatch come into play. It also discusses parametric method and interfaces, for which different functions can work with each other properly based on a pre-determined contract.

- Chapter 4, Macros and Metaprogramming Techniques, introduces macro programming facility and how it can be used to transform source code into a different form. It describes several techniques for developing and debugging macros more effectively.

- Chapter 5, Reusability Patterns, covers design patterns that relate to code reuse. This includes the Delegation pattern for reusing code via composition, the Holy Traits pattern for a more formal interface contract, and the Parametric Type pattern for creating new types from a parameterized data structure.

- Chapter 6, Performance Patterns, covers design patterns that relate to improving system performance. This includes the Global Constant pattern for better type stability, the Memoization pattern for caching prior computation results, the Struct of Arrays pattern for rearranging data for a more optimal layout, the Shared Array pattern for optimizing memory usage with parallel computing, and the Barrier Function pattern for improving performance via function specialization.

- Chapter 7, Maintainability Patterns, covers design patterns about code maintainability. This includes the Sub Module pattern for better organization of larger code bases, the Keyword Definition pattern for creating data types that can be constructed more easily, the Code Generation pattern for defining many similar functions with less code, and the Domain-Specific Language pattern for creating a new syntax for a specific domain.

- Chapter 8, Robustness Patterns, covers design patterns that help you write safer code. This include the Accessor pattern for providing standard access to fields, the Property pattern for controlling access to fields, the Let-Block pattern for limiting the variable scope, and the Exception Handling pattern for handling errors.

- Chapter 9, Miscellaneous Patterns, covers several design patterns that do not fit into the preceding categories. It includes the Singleton Type pattern for use with dynamic dispatch, the Mocking pattern for building isolated tests, and the Functional Pipe pattern for building linear data processing pipelines.

- Chapter 10, Anti-Patterns, covers patterns that should be avoided. The main anti-pattern is Piracy, which involves defining or extending functions for data types that you do not own. Then, it covers the Narrow Arguments and Non-Concrete Type Fields patterns, which hinder system performance.

- Chapter 11, Traditional Object-Oriented Patterns, covers the traditional object-oriented patterns described in the Design Patterns book by Gang-of-Four. It discusses how those patterns can be simplified or implemented differently in Julia.

- Chapter 12, Inheritance and Variance, discusses how Julia supports inheritance and why it is designed as such since its approach is quite different from mainstream object-oriented programming languages. Then, it covers the topic of type variance, an important concept in terms of subtyping relationships between data types used by multiple dispatch.