What is the benefit of never in typescript

Question

I have just started with typescript and read about the type never. But I did not get the actual purpose of it. From this

I got, any code that is not going to execute or unreachable is marked as never

// Type () => never
const sing = function() {
    while (true) {
        console.log("Never gonna give you up");
        console.log("Never gonna let you down");
        console.log("Never gonna run around and desert you");
        console.log("Never gonna make you cry");
        console.log("Never gonna say goodbye");
        console.log("Never gonna tell a lie and hurt you");
    }
};

The function in above code has an infinite loop so that will be marked as never, so what is the benefit of this?

Answer 1

For your example, the benefit is to guarantee that you wont create a escape from your function.

Try to explicitly set the never return type.

const sing = function():never {
    while (true) {
        console.log("Never gonna give you up");
        console.log("Never gonna let you down");
        console.log("Never gonna run around and desert you");
        console.log("Never gonna make you cry");
        console.log("Never gonna say goodbye");
        console.log("Never gonna tell a lie and hurt you");

        break; // Error
    }
};