Hands-On Full Stack Web Development with Angular 6 and Laravel 5

Using the void type

In TypeScript, it is mandatory to define the type of the return of a function. When we have a function that does not have a return, we use a type called void.

Let's see how it works:

Create a new file called void.ts inside the chapter-02 folder, and add the following code:

function myVoidExample(firstName: string, lastName: string): string {    return firstName + lastName;}console.log(myVoidExample('Jhonny ', 'Cash'));

In the preceding code, everything is OK, because our function returns a value. If we remove the return function, we will see the following error message:

void.ts(1,62): error TS2355: A function whose declared type is neither 'void' nor 'any' must return a value.

In VS Code, you would see the following: