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A callback function is a function that is passed as an argument to another function. The callback function is called when the other function is finished.
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What is a callback function?
A callback function is a function that is passed as an argument to another function. The callback function is called when the other function is finished executing. Callback functions are used to handle asynchronous events.
What is a higher-order function?
In JavaScript, a higher-order function is a function that can take another function as an argument, or that returns a function as a result.
A simple example of a higher-order function is the built-in array method map(). The map() method accepts a callback function as its first argument and calls that callback function once for each element in the array:
const numbers = [1, 2, 3, 4, 5];
const doubledNumbers = numbers.map(number => number * 2);
console.log(doubledNumbers);
// [2, 4, 6, 8, 10]
How are callback functions used in JavaScript?
A callback function is a function that is passed as an argument to another function. When the other function is executed, the callback function is called.
Callback functions are used in JavaScript to:
-create asynchronous code
-perform complex tasks
-manipulate data
-interact with APIs and libraries
A callback function is passed as an argument to another function. When the other function is executed, the callback function is called.
What are some examples of callback functions in JavaScript?
A callback function is a function that is passed as an argument to another function.
For example, say we have a simple function that adds two numbers together. We could write this function like so:
function add(a, b) {
return a + b;
}
Now, say we want to create a more complex function that takes two numbers and then passes them to the add function as arguments. We could do this by creating a callback function:
function addNumbers(a, b, callback) {
return callback(a, b);
}
