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: plugins.rb
    path of file: ./repos/guard/lib/guard/internals
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require "guard/plugin_util"

module Guard
  # @private api
  module Internals
    class Plugins
      def initialize
        @plugins = []
      end

      def 
    
      def matcher_for(filter)
        case filter
        when String, Symbol
          shortname = filter.to_s.downcase
          ->(plugin) { plugin.name == shortname }
        when Regexp
          ->(plugin) { plugin.name =~ filter }
        when Hash
          lambda do |plugin|
            filter.all? do |k, v|
              case k
              when :name
                plugin.name == v.to_s.downcase
              when :group
                plugin.group.name == v.to_sym
              end
            end
          end