You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: taggable.rb
    path of file: ./repos/qaror/lib/extender
    
    the code of the file until where you have to start completion: # encoding: utf-8
module Extender
  module Taggable
    
    def self.included(base)
      base.send :include, InstanceMethods
      base.extend ClassMethods
      base.relate
    end

    module ClassMethods
      def relate
        has_many :tag_rels, :as => :taggable, :depen
    
      def relate
        has_many :tag_rels, :as => :taggable, :dependent => :destroy
        has_many :tags, :through=> :tag_rels
        accepts_nested_attributes_for :tags
        before_destroy :decrement_tags_counter
        
        validates :tagnames, :presence => true
        validate :check_tags

        before_save :set_tags

        def grouped_tags(thr)
          joins(:tags).
          where(:tags=>{:name.matches_any=> thr.tags.map(&:name) }).
          group("tags.name").count(:id)
        end

      end