each-iterator.md

Notes: Each Iterator

Each

The each iterator is used on a collection of data, like an Array, Hash or Range. This iterator will iterate over each element of the collection, one by one, and provide access to each element using the iteration variable. The each iterator will continue to execute until it has reached the end of the collection.

The each iterator is comprised of three pieces:

1. The collection to be iterated
2. The iteration variable to store each value
3. The block of code to be executed in the iteration

In the example below, this iterator will iterate over the veggies array. For each iteration, the vegetable variable will be assigned to the value of the next element in the array, starting with the first. The block of code will be executed for each vegetable variable, which will print out the name of the vegetable.

# A list of veggies
veggies = ["carrot", "yam", "zucchini", "spinach"]

veggies.each do |vegetable|
	puts "a vegetable: #{vegetable}"
end

output:

a vegetable: carrot
a vegetable: yam
a vegetable: zucchini
a vegetable: spinach

In the example below, this iterator will iterate over the names array. For each iteration, the name variable will be assigned to the value of the next element in the array, starting with the first. The block of code will be executed for each name, which will say hello to each person!

# A list of names
names = ["Rey", "Finn", "Han"]

names.each do |name|
  puts "Hello #{name}!"
end

output:

Hello Rey!
Hello Finn!
Hello Han!