Learning JavaScript Data Structures and Algorithms - Third Edition

Interfaces

In TypeScript, there are two concepts for interfaces. The first one is related to assigning a type to a variable. Consider the following code:

interface Person { 
  name: string; 
  age: number; 
} 
 
function printName(person: Person) { 
  console.log(person.name); 
} 

The first concept for the TypeScript interface is that an interface is a thing. It is a description of the attributes and methods an object must have.

This allows editors such as VSCode to have autocomplete with IntelliSense, as shown in the following screenshot:

Now, let's try using the printName function:

const john = { name: 'John', age: 21 }; const mary = { name: 'Mary', age: ...