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JavaScript

Posted by Ethan M
Ethan M
10,637 Points

Don't totally understand this

Hi, so I am getting all my genres but I don't entirely understand this line of code

// get genres 
module.exports.getBooks = function(callback, limit) {
    Genre.find(callback).limit(limit);
};

function(callback, limit) what's the callback?

1 Answer

Steven Parker
Steven Parker
243,656 Points
Steven Parker
Steven Parker
243,656 Points

A callback is another function.

It is generally an anonymous function, or just the name of a previously defined function, that is passed as an argument to a function. The function to which it is passed generally performs some task that takes some time, and the callback function is invoked when the task is complete.