When do I use return in a function?

Question

I learned that "return" in a function means the end of the function. However, I see sometimes there is a return and sometimes not. Isn't it supposed to use "return" for all functions?

well sometimes there is a need to exit and sometimes there is not. — epascarello, Nov 02 '17 at 00:45
And [What does javascript function return in the absence of a return statement?](https://stackoverflow.com/q/1557754/4642212). — Sebastian Simon, Nov 02 '17 at 00:46

score 3 · Accepted Answer · answered Nov 02 '17 at 00:47

3

You use return in two situations:

You need to exit the function before reaching the end.
You need to send a result to the caller.

If you reach the end of a function, it's as if the function ended with return undefined;.

answered Nov 02 '17 at 00:47

Barmar

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score 1 · Answer 2 · answered Nov 02 '17 at 00:47

You can omit return from your function if it just does something without producing a value, and you don't need to exit early. You could also think of functions that don't have a return as having one implicitly at the end of the body. For example:

function noReturn() {
    console.log("Hello World");
}

function withReturn() {
    console.log("Hello World");
    return;
}

function withReturnUndefined() {
    console.log("Hello World");
    return undefined;
}

are identical.

When do I use return in a function?

2 Answers2