Working with Creational Design Patterns
JavaScript design patterns are techniques that allow us to write more robust, scalable, and extensible applications in JavaScript. JavaScript is a very popular programming language, in part due to its place as a way to deliver interactive functionality on web pages. The other reason for its popularity is JavaScript’s lightweight, dynamic, multi-paradigm nature, which means that design patterns from other ecosystems can be adapted to take advantage of JavaScript’s strengths. JavaScript’s specific strengths and weaknesses can also inform new patterns specific to the language and the contexts in which it’s used.
Creational design patterns give structure to object creation, which enables the development of systems and applications where different modules, classes, and objects don’t need to know how to create instances of each other. The design patterns most relevant to JavaScript – the prototype, singleton, and factory patterns – will be explored, as well as situations where they’re helpful and how to implement them in an idiomatic fashion.
We’ll cover the following topics in this chapter:
- A comprehensive definition of creational design patterns and definitions for the prototype, singleton, and factory patterns
- Multiple implementations of the prototype pattern and its use cases
- An implementation of the singleton design pattern, eager and lazy initialization, use cases for singleton, and what a singleton pattern in modern JavaScript looks like
- How to implement the factory pattern using classes, a modern JavaScript alternative, and use cases
By the end of this chapter, you’ll be able to identify when a creational design pattern is useful and make an informed decision on which of its multiple implementations to use, ranging from a more idiomatic JavaScript form to a classical form.