What are rest and spread parameters in JavaScript?

Can you explain what rest and spread parameters are in JavaScript?

Sure! Rest parameters allow you to represent an indefinite number of arguments as an array, while spread syntax allows you to expand an array into individual elements.

Can you give me an example of how to use rest parameters?

Absolutely! Here's an example: function sum(...numbers) { return numbers.reduce((acc, num) => acc + num, 0); } This function takes any number of arguments and returns their sum.

And how about spread parameters?

For spread parameters, you can use it like this: const arr = [1, 2, 3]; const newArr = [...arr, 4, 5]; This creates a new array that includes all elements from arr plus 4 and 5.

What are some common use cases for these features?

Common use cases include merging arrays, creating functions that accept variable numbers of arguments, and destructuring objects.