Return statement JavaScript

Question

//Why do we need to use return statement?

//For example:

function add (x, y) {
console.log(x + y);
}
add(10,20); // Will work and value will be 30.

//But, if added to reuse in a variable, it won't work?
//Example

let sum = add(10,20);
//Value will be undefined? Why?

Answer 1

Functions are small blocks of code that will do things or return things:

Your function is a do something function
In your example:

function add(x, y){
console.log(x + y)
}

any call to add will ask the function add to output (x + y) on the standard output stream

to have your function return something so you can reuse it you have to use the return keyword

function add(x, y) {
return x + y;
}

This is going to return the x + y back to the caller.

let sum = add(10, 20)
sum will now be assigned the value of 30

You could also:

console.log(add(10,20))
and get the same out put of 30 like in the first example.

Hope that helps, happy coding.

Answer 2

Jonathan P. Jundarino

Because you didn't return value.

learn about 'return'

Answer 3

The community is full of some great individuals sharing information. Wish you well my friend.

Answer 4

A͢J thanks. I returned to comment section of return statement inside JavaScript course here. So, when we assign the function inside a variable, it will only do it's job, which is computing the expression. "If you tell me to compute 3+3 then I will only compute" I read something like that. So that's why we need return statement.

Answer 5

William Owens thanks so much. I love sololearn community because of people who will answer the questions.