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: clash.rb
    path of file: ./repos/stackneveroverflow/vendor/bundle/ruby/2.3.0/gems/hashie-3.5.5/lib/hashie
    
    the code of the file until where you have to start completion: require 'hashie/hash'

module Hashie
  #
  # A Clash is a "Chainable Lazy Hash". Inspired by libraries such as Arel,
  # a Clash allows you to chain tog
    
    def method_missing(name, *args) #:nodoc:
      if args.empty? && name.to_s.end_with?('!')
        key = name[0...-1].to_sym

        case self[key]
        when NilClass
          self[key] = self.class.new({}, self)
        when Clash
          self[key]
        when Hash
          self[key] = self.class.new(self[key], self)
        else
          fail ChainError, 'Tried to chain into a non-hash key.'
        end