Scope chaining

User.admins            # return all admins
User.editors           # return all editors
User.admins.editors    # return all users that are admins and editors
User.not.admins        # return all users that are not admins
User.admins.or.editors # return all users that are admins or editors

class Job < ActiveRecord::Base
  def search(options)
    Job.
      active.unless { options[:include_inactive] }.
      group {|jobs|
        jobs.
          titled(options[:title]).or.
          matching_company_name(options[:company]).or.
          tagged_with(options[:tags])
      }
    end
  end
end