my %defaults = ( 'other1' => 'default1',
                   'other2' => 'default2' );
  my %from_cmdline = process_command_line();
  my $config = $from_cmdline{config} || "default.config";
  my %from_config = read_config_file($config);
  my %opts = (%defaults, %from_config, %from_cmdline);