Interface Declaration

An interface in TypeScript is a blueprint for creating objects with specific structure. An interface defines a set of properties, methods, and events that a class or object must implement. The interface is a contract between objects and classes and can be used to enforce a specific structure for objects in your code.

Here is an example of an interface declaration in TypeScript:

interface Person {
  firstName: string;
  lastName: string;
  age?: number;

  getFullName(): string;

In this example, the Person interface defines four properties: firstName, lastName, age, and a method getFullName(). The age property is optional, indicated by the ? symbol. Any class or object that implements the Person interface must have these properties and method.

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