Types of iterators in Ruby

In Ruby, we have multiple types of iterators available to us. We will learn about the most common ones in this article, one by one.

Each Iterator

Using this iterator, you can iterate over an array or a hash, returning each element as it is returned.

Example 1

Consider the code shown below

# each iterator example
(0..10).each do |itr|
   puts itr
end

Output

0
1
2
3
4
5
6
7
8
9
10

Times Iterator

This iterator implants a loop with a specific number of iterations. The loop starts from zero and runs until it gets one less than the specified number.

Example 2

# time iterator example
5.times do |itr|
   puts itr
end

Output

0
1
2
3
4

Collect Iterator

The collect iterator returns the elements of the collection in an array or hash, regardless of the type of collection it is.

Example 3

# collect iterator example
arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
res = arr.collect{ |y| (4 * y) }
puts res

Output

4
8
12
16
20
24
28
32
36
40
44
48