kaminari--kaminari/lib/kaminari/models/active_record_model_extension.rb

require 'kaminari/models/active_record_relation_methods'

module Kaminari
  module ActiveRecordModelExtension
    extend ActiveSupport::Concern

    included do
      self.send(:include, Kaminari::ConfigurationMethods)

      # Fetch the values at the specified page number
      #   Model.page(5)
      eval <<-RUBY
        def self.#{Kaminari.config.page_method_name}(num = nil)
          limit(default_per_page).offset(default_per_page * ((num = num.to_i - 1) < 0 ? 0 : num)).extending do
            include Kaminari::ActiveRecordRelationMethods
            include Kaminari::PageScopeMethods
          end
        end
      RUBY
    end
  end
end