What are some advanced enumerable methods in Ruby on Rails?

What are some advanced enumerable methods in Ruby on Rails?

In Ruby on Rails, advanced enumerable methods include inject, map, select, and group_by. These methods allow for powerful data manipulation.

Can you explain how the inject method works?

Sure! The inject method is used to accumulate a value across the elements of an enumerable. It takes an initial value and a block, applying the block to each element.

Can you give me an example of using map?

Absolutely! If you have an array of numbers, map can transform each number. For example, [1, 2, 3].map { |n| n * 2 } results in [2, 4, 6].

What about select? How is it different from map?

select filters elements based on a condition. Unlike map, which transforms elements, select returns only those that meet the criteria. For example, [1, 2, 3].select { |n| n.even? } returns [2].