Question

Possible Duplicate:
Is there a difference between a function with and without a return statement?

Are there differences between an empty function and a function that only returns nothing?

Empty function:

function a() {
}

Function that only returns nothing:

function b() {
    return;
}

Answer 1

No, the return is implied if omitted in the first one. Both of them return undefined.

// In the console:
a();
// undefined
b();
// undefined

To expand a little further, this isn’t the same as returning null:

function c() {
    return null;
}

c();
// null (which is a value, albeit a null one)

// Because
a() === c();
// false
null === undefined;
// false