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: dir.rb
    path of file: ./repos/writing-a-compiler-in-ruby/lib/core
    
    the code of the file until where you have to start completion: 
class Dir
  def self.pwd
    %s(assign wd (get_current_dir_name))
    %s(assign cwd (__get_s
    
  def self.pwd
    %s(assign wd (get_current_dir_name))
    %s(assign cwd (__get_string wd))
    cwd = cwd.dup
    %s(free wd)
    return cwd
  end