# File lib/gettext_i18n_rails/ruby_gettext_extractor.rb, line 60
    def extract_key_singular(args, separator)
      key = extract_string(args) if args.size == 2 || args.size == 4

      return nil unless key
      key.gsub("\n", '\n').gsub("\t", '\t').gsub("\0", '\0')
    end