What are the differences between map, select, and each in Ruby?

What are the differences between map, select, and each in Ruby?

In Ruby, map, select, and each are all enumerable methods but serve different purposes. map transforms each element in an array and returns a new array, select filters elements based on a condition, and each simply iterates over elements without returning a new array.

Can you give me examples of each method?

Sure! For map, you can do something like array.map { |n| n * 2 }, which doubles each element. For select, you might use array.select { |n| n.even? } to get only even numbers. And for each, you could write array.each { |n| puts n } to print each element.

When should I use each instead of map?

Use each when you want to perform an action on each element without needing a new array. Use map when you want to transform the elements and need the results in a new array.

Are there performance differences between these methods?

Yes, there can be performance differences. each is generally faster since it doesn't create a new array, while map and select involve creating new arrays, which can be slower for large datasets.