JavaScript, Factory Function JavaScript

Explain JavaScript Factory Functions. How to recognize it?
Answer: JavaScript Factory Functions are a pattern used for creating objects in JavaScript. Unlike constructor functions or classes, factory functions do not use 'new' to instantiate objects. Instead, they simply return a new object when called.1. Returns an Object: The main purpose of a factory function is to create and return an object.
2. No 'new' Keyword: Unlike constructor functions, factory functions do not require the 'new' keyword to create instances.
3. Encapsulation: Factory functions encapsulate the object creation process, allowing you to initialize properties, perform computations, or set up the object in a controlled manner.
4. Customization: They can accept parameters to customize the created objects based on the inputs provided.
// Factory function example
function createPerson(name, age) {
return {
name: name,
age: age,
greet() {
console.log('Hello, my name is ${this.name} and I am ${this.age} years old.');
}
};
}
// Usage
const person1 = createPerson('Alice', 30);
const person2 = createPerson('Bob', 25);
person1.greet(); // Output: Hello, my name is Alice and I am 30 years old.
person2.greet(); // Output: Hello, my name is Bob and I am 25 years old.
- Naming Convention: Factory functions often use verbs or descriptive names to indicate their purpose, such as 'createSomething', 'makeSomething', etc.
- Return Statement: They always return an object literal ('{ ... }') or a new instance of an object, without using 'new'.
- Encapsulation: They encapsulate object creation logic, often including initialization and configuration within the function body.
Factory functions are versatile and can be used in various scenarios where you need to create multiple instances of objects with similar properties and behaviors, providing a cleaner and more flexible alternative to constructor functions in JavaScript.