setTimeout(myFunction, 5000); vs setTimeout(myFunction(), 5000);

Question

I was playing around with the \"setTimeout\" function. This code runs like expected:

function myFunction() {
    console.log(\'test\');
    setTimeout(myFunction         


        

Answer 1

myFunction() calls the function immediately and passes its return value to setTimeout to be called later (except its return value is undefined, which isn't a function (or a string), so that is pointless).

Answer 2

That is because by including the parentheses you're actually executing the function and passing its result to setTimeout.

Answer 3

setTimeout(myFunction(), 1000); means that your pass result returned by myFunction() as the 1st argument of setTimeout. myFunction returns nothing, so setTimeout(myFunction(), 1000); is the same as setTimeout(undefined, 1000);