I'm confused about the return statement.

Question

In this particular video, Dave returns two arguments and an empty string that are concatenated. I get that, but what I don't understand is how he says only one value can be returned by a return statement. If you concatenate different data types, does that mean it is considered one statement? Also it is to my understanding that the return statements exits a function. Out of curiosity, what happens if you have two functions in which the first one did not have a return statement, and the second one does? Is this even possible?

Chyno Deluxe · Accepted Answer

The return keyword allows you to send data back from a particular function. For example.
```javascript
function addNum(num1, num2){
  return num1 + num2;
}
addNum(5, 10); // returns 15
```
The return keyword lets the function know that when the function is call, it must send back data. However, notice the difference when you omit the return keyword.
```javascript
function addNum(num1, num2){
  num1 + num2;
}
addNum(5, 10); // undefined
```
Demo jsFiddle (https://jsfiddle.net/1Lhoopap/)
Not all functions require the return keyword. Only in cases where you need/want to test certain conditions and only return the response of those conditions.
I hope this helps. Feel free to ask me if you still have questions

Ran ShemTov · Answer

You'd use a function with no return value to manipulate data.
lets say i have a div with the ID of "bar" i want to dinamiclly set html in. i'd do:

function foo(html){
     document.getElementById("bar").innerHTML=html;
}

no return. it will manipulate the dom and end the function. I do not need any value back

jag · Answer

```html
If you concatenate different data types, does that mean it is considered one statement? 
```
If you concat different values into one when it's returned it will be one value. 
```html
Also it is to my understanding that the return statements exits a function. 
```
Yes, which is why multiple returns can't be done.
```html
Out of curiosity, what happens if you have two functions in which the first one did not have a return statement, and the second one does? 
Is this even possible?
```
Without a return statement you just won't get a value. These functions exist to do other stuff but the way in the video it's being used is to concat and return the value. 
Both functions are done. 
Here is a codepen example (http://codepen.io/anon/pen/akYwyv).

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Jonathan Martinez

Jonathan Martinez

I'm confused about the return statement.

3 Answers

Chyno Deluxe

Chyno Deluxe

jag

jag

Ran ShemTov

Ran ShemTov