Ruby pagination example with extend

pagination.rb

module Pagination
  def paginate(page = 1, items_per_page = size, total_items = size)
    @page = 1
    @items_per_page = items_per_page
    @total_items = total_items
  end
  
  attr_reader :page, :items_per_page, :total_items
  
  def total_pages
    (total_items / items_per_page).ceil
  end
  
end

collection = %w[first second third]

collection.extend(Pagination)
collection.paginate(1, 3, 10)

p "There are #{collection.total_pages} items."
p "The collection is an Array." if collection.is_a?(Array)
p "The collection is a paginated collection" if collection.is_a?(Pagination)

collection = {first: 1, second: 2, third: 3}
collection.extend(Pagination)
collection.paginate(1, 3, 10)

p "There are #{collection.total_pages} items."
p "The collection is an Hash." if collection.is_a?(Hash)
p "The collection is a paginated collection" if collection.is_a?(Pagination)