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JavaScript Asynchronous Programming with JavaScript Asynchronous JavaScript with Callbacks Callback Functions Review

What is the answer to this question and what is the rationale for this question?

return cb();

1 Answer

Hi Hanwen!

cb is the callback function that is passed into the makemeal function as a parameter.

Having passed it in, it would make sense to then execute it at some point inside the execution of makemeal (otherwise, what's the point of passing it in?!?).

So for this:

function makeMeal(meal, cb) {
  alert(`Preparing ${meal}.`);
  cb(); // YOU WANT TO CALL the cb funtion to execute it. (However, there's no need to return it, you're just running it.)
}

makeMeal('lunch', () => { // This is cb passed in as an anonymous function argument
  alert('Finished the meal!');
});

I hope that helps.

Stay safe and happy coding!

Thank you Peter!!