Detailed usage of ts extends

TypeScript's extends keyword allows inheritance of properties and methods from a base class to a derived class. While beneficial for code reuse and polymorphism, it has drawbacks such as lack of multiple inheritance, tight coupling, and abstraction l

How can I leverage the extends keyword to inherit functionality and properties in TypeScript?

In TypeScript, the extends keyword is used to create a derived class (or child class) that inherits properties and methods from a base class (or parent class). To inherit from a base class using the extends keyword, you can follow these steps:extends keyword is used to create a derived class (or child class) that inherits properties and methods from a base class (or parent class). To inherit from a base class using the extends keyword, you can follow these steps:

1. Define the base class with its properties and methods.
2. Use the extends keyword to define a derived class, specifying the base class as the parent class.
3. Access the properties and methods of the base class within the derived class using the super keyword.

For example, consider the following base class:

<code>class Animal {
  name: string;
  age: number;

  constructor(name: string, age: number) {
    this.name = name;
    this.age = age;
  }

  speak() {
    console.log("Animal speaks");
  }
}</code>

To create a derived class that inherits from the Animal class, we can use the extends keyword as follows:

<code>class Dog extends Animal {
  breed: string;

  constructor(name: string, age: number, breed: string) {
    super(name, age);  // Call the base class constructor
    this.breed = breed;
  }

  speak() {
    console.log("Dog barks");
  }
}</code>

In the Dog class, we extend the Animal class, inheriting its properties and methods. We can access the name and age properties inherited from the Animal class using the super keyword, and we can also define new properties and methods specific to the Dog class, such as the breed property and the speak method.

What are the drawbacks and limitations of using the extends keyword in TypeScript?

The extends keyword in TypeScript is a powerful tool for inheriting functionality and properties from a base class, but it also has some drawbacks and limitations to consider:

• Multiple inheritance is not supported: TypeScript does not support multiple inheritance, which means that a derived class can only inherit from a single base class.
• Tight coupling: Classes that use the extends keyword are tightly coupled to their base classes. Changes made to the base class can affect the derived class, potentially breaking its functionality.
• Lack of abstraction: Derived classes that rely heavily on the implementation details of their base classes can lack abstraction, making it difficult to maintain and extend the codebase.

When and why should I prefer using the extends keyword over other inheritance mechanisms in TypeScript?

The extends

Define the base class with its properties and methods.

• Use the extends keyword to define a derived class, specifying the base class as the parent class.
• Access the properties and methods of the base class within the derived class using the super keyword.
• For example, consider the following base class:
rrreee

rrreee

• What are the drawbacks and limitations of using the extends keyword in TypeScript?
• The extends keyword in TypeScript is a powerful tool for inheriting functionality and properties from a base class, but it also has some drawbacks and limitations to consider:

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