You can think of the each method as one that operates a block, or a specific piece of code, onto each element in your collection. For example, if we had a collection of toys we might store these in an array. If we wanted to print each toy on the screen, we can call the each method. In the example below, we create the toys array with our collection of toys, then we call each specific toy individually.
toys = [
"car",
"ball",
"action figure",
"stuffed animal"
]
toys.each { |toy| puts toy }
# Now each toy will be put to the screen:
car
ball
action figure
stuffed animal
Let’s dig into the each method to see what we did. Since this method belongs to the Array class, we can call it on our toys array. We then give our each method a block of code to be executed or carried out and performed. In this case, we are using the puts method. In our |pipes| we define a temporary variable toy and call the puts method on each toy that is passed to our block.
Our each method knows to look at each element (our four toys) inside the array. This is called iterating over the array. (Iterating over the array is just a fancy way of saying look at each toy in the collection). Now we store the value of each array element inside our |pipes| and call the puts method on each element. We could have written the same code like so:
toys.each do |toy|
puts toy
end
The curly brackets are a way of writing do and end in one line. You don’t have to use them, but it is a shortcut that you can use if you want! Either way works, and Ruby will look to execute the code inside of our do end or { } block. Now, let’s look at how we might use the each method on a hash.
Imagine we had more than one toy in our collection. (If your parents are teaching you how to code in Ruby, you probably have a lot more than one toy in your collection. Lucky you!) We might use a hash to better represent or organize our toy box. Using each, we can print the toy and the number of toys in our collection.
toys = {"car" => 1, "ball" => 3, "action figure" => 2,
"stuffed animal" => 8}
toys.each { |key, value| puts "#{key} => #{value}" }
car => 1
ball => 3
action figure => 2
stuffed animal => 8
When using the each method on a hash, Ruby knows that each element in the array has a key and a value. We could have used anything in our |pipes| to name our key and value pairs ( such as |x, y| ), but it’s easier to read when we identify our key and value by their names. We then call the puts method again on each element, use our friend interpolation #{ } to place our variable values in our string, and finally put the string of the toy, and number of toys, to the screen.