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: dabbrev.rb
    path of file: ./repos/textbringer/lib/textbringer/commands
    
    the code of the file until where you have to start completion: module Textbringer
  module DabbrevExtension
    refine Buffer do
      def dabbrev_expand(contd = false)
        if contd && self[:dabbrev_stem]
          buffers 
    
      def dabbrev_expand(contd = false)
        if contd && self[:dabbrev_stem]
          buffers = self[:dabbrev_buffers]
          buffer = self[:dabbrev_buffer]
          stem = self[:dabbrev_stem]
          pos = self[:dabbrev_pos]
          direction = self[:dabbrev_direction]
          candidates = self[:dabbrev_candidates]
        else
          buffers = Buffer.to_a
          buffers.delete(self)
          buffer = self
          stem = get_stem_at_point
          pos = point
          direction = :backward
          candidates = []
        end