What are filter and reduce in functional programming?

What are filter and reduce in functional programming?

Filter and reduce are higher-order functions used to process collections. Filter creates a new array with elements that pass a test, while reduce aggregates values into a single result.

Can you give me an example of how to use filter?

Sure! If you have an array of numbers, you can use filter to get only the even numbers: const evens = numbers.filter(num => num % 2 === 0);

And how about reduce? What does it look like?

For reduce, you can sum up all the numbers in an array like this: const total = numbers.reduce((acc, num) => acc + num, 0); This adds each number to an accumulator.

Are there any performance considerations when using these methods?

Yes, using filter and reduce can be less performant than traditional loops for large datasets, as they create new arrays and involve function calls.