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: c.rb
    path of file: ./repos/artichoke/artichoke-backend/vendor/ruby/lib/rdoc/parser
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
require 'tsort'

##
# RDoc::Parser::C attempts to parse C extension files.  It looks for
# the standard patterns that you find in extensions: +rb_define_cla
    
  def rb_scan_args method_body
    method_body =~ /rb_scan_args\((.*?)\)/m
    return '(*args)' unless $1

    $1.split(/,/)[2] =~ /"(.*?)"/ # format argument
    format = $1.split(//)

    lead = opt = trail = 0

    if format.first =~ /\d/ then
      lead = $&.to_i
      format.shift
      if format.first =~ /\d/ then
        opt = $&.to_i
        format.shift
        if format.first =~ /\d/ then
          trail = $&.to_i
          format.shift
          block_arg = true
        end