each_with_object.rb

# http://blog.flatironschool.com/post/35154441787/rubys-each-with-object

hash = {}
['red', 'green', 'blue'].each do |color|
  hash[color] = 'primary'
end

# Using inject, we don't have to initialize the hash ahead of time

['red', 'green', 'blue'].inject({}) do |hash, color|
  hash[color] = 'primary'
  hash
end

# by using each_with_object you don't need to return like hash at the end.

['red', 'green', 'blue'].each_with_object({}) do |hash, color|
  hash[color] = 'primary'
end